How to Prevent 5 Common Welding Gun Failures

How to Prevent 5 Common Welding Gun Failures

Having the right equipment in the welding operation is important — and making sure it works when it’s needed is even more so.

Welding gun failures cause lost time and money, not to mention frustration. Like with many other aspects of the welding operation, the most important way to prevent this problem is education. Understanding how to properly choose, set up and use a MIG gun can help optimize results and eliminate many of the problems that lead to gun failure. 

Learn about five common reasons MIG guns fail and how to prevent them.

Welder welding with a Bernard GMAW gun as sparks fly
Understanding how to properly choose, set up and use a MIG gun can help optimize results and eliminate many of the problems that lead to gun failure.

Reason No. 1: Exceeding the gun rating

The rating on a MIG gun reflects the temperatures above which the handle or cable becomes uncomfortably warm. These ratings do not identify the point at which the welding gun risks damage or failure. 

Much of the difference lies in the duty cycle of the gun. Because manufacturers can rate their guns at 100%, 60% or 35% duty cycles, there can be significant variances when comparing manufacturer’s products.

Duty cycle is the amount of arc-on time within a 10-minute period. One manufacturer may produce a 400-amp GMAW gun that is capable of welding at 100% duty cycle, while another manufactures the same amperage gun that can weld at only 60% duty cycle. The first gun would be able to weld comfortably at full amperage for a 10-minute time frame, whereas the latter would only be able to weld comfortably for 6 minutes before experiencing higher handle temperatures.

Choose a gun with an amperage rating that matches the necessary duty cycle required and the length of time that the operator will be welding. It’s also important to consider the materials and filler metal wire that will be used. The gun should be able to carry enough power to melt the filler metal wire cleanly and consistently.

Reason No. 2: Improper setup and grounding

Improper system setup can increase the risk of welding gun failure. It’s important to pay attention to not only all consumable connections within the gun, but also all connections in the entire weld circuit to optimize performance.

Proper grounding helps ensure the operator isn’t sending too much power to a restricted window for the power to travel through. Loose or improper ground connections can increase resistance in the electrical circuit.

Be sure to put the ground as close to the workpiece as possible — ideally on the table that holds the workpiece. This helps provide the cleanest circuit structure for the power to travel where it needs to go.

Welder welding a rectangular frame with a MIG gun
Welding gun failures cause lost time and money, not to mention frustration. Like with many other aspects of the welding operation, the most important way to prevent this problem is education.

It’s also important to place the ground on clean surfaces so there is metal-to-metal contact; do not use a painted or dirty surface. A clean surface gives the power an easy path to travel rather than create obstructions that create resistance — which increases heat. 

Reason No. 3: Loose connections 

Consumable connections play an important role in gun performance. Consumables should be tightly secured to the gun, and all threaded connections should also be secure. It’s especially important to check and tighten all connections after a gun has been serviced or repaired.

A loose contact tip or gun neck is an invitation for gun failure at that spot. When connections aren’t tight, heat and resistance can build up. Also, be sure any trigger connect being used is working properly and provides constant power.

Reason No. 4: Damaged power cable

Cables can be easily damaged in the shop or manufacturing environment; for example, by heavy equipment or improper storage. Any damage to the power cable should be repaired as quickly as possible.

Inspect the cable for any cuts or damage; no copper should be exposed in any part of the cable. An exposed line of power in the weld system will try to jump the arc if it touches anything metallic outside of the system. This can result in a wider system failure and a possible safety concern.

Re-terminate the gun and make the cable shorter if necessary, removing any cable sections that have nicks or cuts. 

Also be sure the power cable is the proper size for the power that the feeder is supplying to the weld gun. An oversized power cable adds unnecessary weight, while an undersized cable causes heat buildup.

Welder welding with a stars and stripes helmet, Miller welding jacket
Choose a gun with an amperage rating that matches the necessary duty cycle required and the length of time that the operator will be welding.

Reason No. 5: Environmental hazards

The manufacturing environment can be harsh for tools and equipment. Take care of tools and equipment to help extend their useful life. Skipping maintenance or treating tools poorly can result in failure and reduced life.

If the welding gun is connected to a boom arm above the weld cell, make sure there are no areas where the gun or cable can be pinched or damaged. Set up the cell so there is a clear path for the cable, to avoid crushing the cable or disrupting shielding gas flow.

Using gun anchors helps keep the gun in a good position and the cable straight — to avoid excessive strain on the cable — when the gun isn’t being used.

Additional thoughts on MIG gun failures

Gun failures in water-cooled welding guns typically happen more frequently than failures in air-cooled gun models. This is primarily due to improper setup.

A water-cooled welding gun requires coolant to chill the system. The coolant must be running before the gun is started because the heat builds quickly. Failure to have the chiller running when welding starts will burn up the gun — requiring replacement of the entire gun.

Welder knowledge and experience regarding how to choose between these guns and maintain them can help prevent many of the issues that result in failures. Small issues can snowball into larger issues within the system, so it’s important to find and address problems with the welding gun when they start to avoid bigger troubles later.

Maintenance Tips

Following some basics tips for preventive maintenance can help extend the life of the welding gun and keep it operating smoothly. It also helps reduce the chances of reactive emergency maintenance that can take the weld cell out of commission.

Regularly inspecting the MIG gun can be an important part of reducing costs and gaining good welding performance. Preventive maintenance doesn’t have to be time-consuming or difficult.

Check the feeder connection regularly. Loose or dirty wire feeder connections cause heat to build up and result in voltage drops. Tighten connections as needed and replace damaged O-rings as necessary.

Properly care for the gun liner. Gun liners can often become clogged with debris during welding. Use compressed air to clear any blockages when wire is changed. Follow manufacturer’s recommendations for trimming and installing the liner.

Inspect the handle and trigger. These components typically require little maintenance beyond visual inspection. Look for cracks in the handle or missing screws, and be sure the gun trigger isn’t sticking or malfunctioning.

Check the gun neck. Loose connections at either end of the neck can cause electrical resistance that results in poor weld quality or consumable failures. Ensure all connections are tight; visually inspect the insulators on the neck and replace if damaged.

Inspect the power cable. Regularly checking the power cable is important to reduce unnecessary equipment costs. Look for any cuts or kinks in the cable and replace as necessary.

Republished from Welding Journal (August 2020) with permission from the American Welding Society (AWS). Click here to view the original article.


From Semi-Automatic to Automatic: Tips for Selecting a Welding Gun

From Semi-Automatic to Automatic: Tips for Selecting a Welding Gun

Choosing the right equipment for a welding operation is critical to achieving high weld quality and productivity while also eliminating costly downtime. And that includes welding guns.

In many cases, companies may have a mix of welding processes and guns. For example, in heavy equipment and general manufacturing, it’s common to have semi-automatic welding along with robotic welding. In oil and gas and shipbuilding applications, semi-automatic welding and fixed automation are prevalent. The combination of welding processes and equipment allows companies serving these industries to weld a variety of part volumes and sizes.

These process mixes, however, can pose challenges in terms of gun selection. That’s why it’s important to know the best welding gun features to look for to achieve the desired weld results — and the best efficiencies.

This article has been published as a web-exclusive on thefabricator.com. To read the entire story, please click here.


The Importance of Cutting a Welding Liner Properly

The Importance of Cutting a Welding Liner Properly

Installing a welding liner correctly is, first and foremost, a matter of proper training. For traditional systems, it’s critical that welding operators understand how to measure and cut the liner to the required length for the gun. 

A welding liner that has been cut either too short or too long can lead to a host of issues, most often poor wire feeding. That, in turn, can lead to weld quality issues and rework — both factors that contribute to unnecessary and costly downtime. 

The Bernard® AccuLock™ S Consumable System can help eliminate installation issues. First, however, it’s important to understand the pitfalls of standard liner installation to understand the value of this solution. 

The problem
The position of the gun and power cable factors significantly into whether liner installation is successful. If the gun and power cable are twisted or coiled before the welding operator trims the liner, the liner can end up either too long or too short, due to how the cable is constructed. 

Inside the power cable is copper that is wound around a central conduit in a helix or spiral. If the cable is twisted or coiled, it will grow or shrink based on how the copper helix is also twisted. Think of a spring — if it is twisted one way, it grows; if twisted the other way, it shrinks.  

For this reason, it’s important to lay the gun and cable straight to avoid any kinks that would lead to an incorrect reading when trimming the liner. Generally, longer power cables are more prone to twisting, so welding operators must take even more care when installing liners in them. 

Welding operators may experience the following due to an improperly trimmed liner:

  • Poor wire feeding
  • Erratic arc
  • Birdnesting
  • Burnbacks
  • Wire chatter

A new solution

The Bernard® AccuLock™ System eliminates the need to measure the liner for replacement. The liner locks into place so it can then be trimmed flush with the power pin cap at the back of the gun and power cable. It is still important to lay the gun and cable flat, avoiding twists. 

Digital image demonstrating how to trim an AccuLock S liner with no measuring required
Digital image of the back end of a BTB semi-automatic MIG gun AccuLock S power pin installed

The welding operator can conduct a visual check to determine the liner is in the proper place. This check isn’t possible with a traditional liner if it has been cut too short; the liner will be hidden under the nozzle and gas diffuser, and not visible to the welding operator. 

The AccuLock System reduces wire feeding issues through the gun, as well, since the liner is locked and concentrically aligned at both the power pin cap and contact tip. This dual lock helps ensure the liner won’t extend or contract as the welding operator changes positions and the power cable naturally bends. The result is the elimination of gaps or misalignments at the front and back of the gun for a flawless wire-feeding path. 

As an added benefit the concentric alignment of the liner reduces mechanical wear on the contact tip that could lead to burnbacks or keyholing, both of which shorten the contact tip life. 

For more information please visit the AccuLock S consumables product page

Tips for Improving MIG Welding

Tips for Improving MIG Welding

Maintaining quality, productivity and cost savings is important in any semi-automatic MIG welding operation, but the steps companies take to achieve those goals vary. Still, there is one constant: the value of skilled welders. They are at the heart of the operation and help ensure its success.

Having the right equipment and understanding how to care for it are also important, as is
revisiting the welding process regularly to ensure its efficiency. Companies should take care to watch for common pitfalls that could negatively affect their progress toward streamlining and improving their operation.

Consider these tips to help along the way:

Welder training

With the industry facing an anticipated welder shortage of 400,000 by 2024, providing training to new welders is critical to supporting a productive and profitable MIG welding operation. In many cases, employees being hired are entirely new to welding or only have limited experience. Learning best practices early on is necessary to achieve the best performance and avoid excessive downtime for troubleshooting.

Welder welding with a semi-automatic MIG gun
Maintaining quality, productivity and cost savings is important in any semi-automatic MIG welding operation.

Gaining good weld quality depends on welders knowing proper techniques like gun angle and gun travel speeds and the impact of welding parameters on the process. Even if a company sets lockouts that keep welding parameters within a specific range, it’s valuable for welders to understand the impact voltage, amperage, wire feed speed and shielding gas have on the application.

It’s also important to provide training on other best practices in the MIG welding operation, such as:

  • Consulting a checklist for maintenance or equipment checks at the beginning and end of each shift. This can include items like securing weld grounding and checking for gun or cable damage.
     
  • Understanding proper ergonomics to prevent repetitive stress injuries. Having welder input on gun handle types can help with this, too.
     
  • How to correctly install consumables and at what frequency, along with how to identify the signs of contact tip wear.
     
  • Keeping the gun uncoiled and untwisted while using it to help avoid liner movement, which typically leads to wire feeding problems.
     
  • As part of training, encourage welders to be open to asking questions and offer refresher courses to keep skills in top shape.

Assessing the process

To support the long-term efficiency of a MIG welding operation, it’s a good idea to regularly assess each aspect of it.

Semi-automatic MIG welding in action
To support the long-term efficiency of a MIG welding operation, it’s good to regularly assess each aspect of it.

Time studies, for example, offer excellent insight into the entire workflow and allow companies to record the amount of time each task takes to complete. These studies include a breakdown and analysis of parts handling, welding and more. By recording every activity in the operation, it is possible to see whether each one is adding value. If not, adjustments and re-sequencing can be made.

Analyzing the operation can also help identify the need for more welder training. For instance, if a significant amount of time is spent grinding after welding, it can indicate that there are issues contributing to overwelding or poor weld quality. The company can then take proactive steps for additional welder training to improve quality and reduce or eliminate the need for grinding and rework.

Similarly, if welders are spending more time transferring parts than they are welding or there are bottlenecks of parts entering the welding cell, that indicates the workflow needs to be adjusted. The goal is to minimize the amount of time welders spend handling or double handling parts and helps avoid parts from backing up or having welders sit idle waiting for them.

Improving the organization of the workstation as part of a general assessment can also help improve welding productivity. This could include adjusting welding tables and part racks to be more ergonomic so welders are more comfortable and can weld longer.

Welding gun selection and use

Having the correct MIG welding gun for the application can help enhance performance in a MIG welding operation.

One of the first things to consider is cost. Quality MIG welding guns carry a higher price, but they are worth it in the long term. A better gun (when used properly) lasts longer and can help improve weld quality and efficiency over time. Guns that feature mechanical compression fittings, as opposed to crimped fittings, are a good choice. They typically last longer from wear and tear and can also be repaired if damaged, which saves money on replacement guns.

Group of three different BTB semi-automatic air-cooled MIG guns being held with gloved hands
Quality MIG welding guns carry a higher price, but they are worth it in the long term. A better gun (when used properly) lasts longer and can help improve weld quality and efficiency over time.

Be certain to choose a gun with the appropriate amperage rating and duty cycle for the application to prevent overheating. A lower amperage MIG welding gun may be appealing to a welder due to its lighter weight and flexibility; however, it will not be able to withstand an application requiring higher amperages and long arc-on times.

Effectively grounding the weld circuit is another way to gain weld quality and productivity in a semi-automatic welding operation. It can also protect the welding gun from overheating and from wearing out consumables too quickly. Installing the ground clamp as close to the weld as possible and limiting the amount of connections can help to prevent one or more from coming loose over time or creating electrical resistance.

Always choose correctly sized ground cables for the weld circuit and the right type of ground clamp. A C-clamp is a good option as it is a tighter connection versus a spring clamp, which helps prevent arcing at the ground that could lead to an erratic arc. As with other quality components in a MIG welding operation, C-clamps can be more expensive, but they offer a connection that can better protect the gun and save on replacement or repair costs.

Lastly, take care to inspect the welding gun cable regularly for damage and replace as necessary. Nicks or cuts in the cable can expose bare copper, causing a safety hazard of electrical shock, as well as erratic welding issues. Adding a cable jacket cover is a proactive step in avoiding these problems.

The role of consumables and wire

Contact tips, nozzles, gas diffusers and liners all affect MIG welding performance. Ideally, select consumables and wire designed to complement one another as a system. These can help maintain solid connections that provide the best electrical conductivity and arc stability.

Always trim the liner properly — per the guns owner’s manual — to avoid erratic arcs and burn backs or look for liners that lock into place and require no measurement to avoid trimming them too long or too short.

For semi-automatic MIG welding, copper contact tips work well; however, if more tip life is desired or needed, chrome zirconium tips are an alternative to better resist physical tip wear (also known as keyholing). It helps to monitor how often contact tips are being changed to avoid straying too far from the originally planned frequency of tip changeover. If tip changes begin to increase drastically, then this points to incorrect installation of consumables, a liner being cut too short or other damage in the system. Monitoring consumables usage can also help identify when contact tips could still have life left in them. If contact tips are changed too early, this results in unnecessary downtime.

Also consider the wire being used. Quality is key here, too. Less expensive wires often have an irregular cast or helix or an inconsistent layer of lubricant. All of these factors can lead to weld quality issues and additional wear on the contact tips.

Keeping on track

Maintaining an efficient MIG welding operation takes time and resources, but it’s worthwhile to make an investment in welders and equipment to achieve the best results. Continue to monitor the process for improvement opportunities and engage welders whenever possible. Since welders are responsible for moving quality and productivity forward, their ideas can be a valuable asset.

Selecting Contact Tips for Robotic Welding

Selecting Contact Tips for Robotic Welding

Contact tips are often referred to as the smallest fuse in the fuse box that is your robotic welding cell. But this small fuse can have a big impact on productivity. In terms of overall efficiency, the contact tip is key.

Contact tips depend upon repeatability to be effective in the welding process. Learn more about the different types of available — and how choosing the right one for your application can improve results and save money.

How do contact tips affect efficiency?
The job of the contact tip is to transfer the welding current to the arc and guide the welding wire as consistently as possible. If either of these two factors degrade, the overall welding process also degrades, affecting quality.

When an operation changes contact tips every few hours, there is an obvious effect on productivity. It requires the weld cell to be shut down, and the operator may have to enter the cell to change out the tip. If the robot is buried inside the welding line, contact tip changeover takes even longer.

Not only are these changeovers inefficient, but they also introduce the potential for mistakes. Every time a human interacts with the robot, there’s a risk of incorrect consumable installation or other improper adjustments that can lead to poor quality welds and costly rework.

Tregaskiss TOUGH GUN TA3 robotic air-cooled MIG gun welding in automation application
Contact tips are often referred to as the smallest
fuse in the fuse box that is your robotic
welding cell. But this small fuse can have
a big impact on productivity.

Choosing the right tip depends on the results you’re looking for and the needs of the application. In the automotive industry, for example, choosing a quality contact tip is critical since unplanned downtime is the enemy of a high-volume multi-robot operation. Contact tips in these applications need more wear resistance.

A high-quality contact tip provides a longer life and a more consistent and stable arc. Longer tip life results in more robot uptime, less time wasted on non-value-added labor for tip changeovers and reduced human interaction with the robot that could lead to error. But the contact tip itself isn’t the only factor impacting tip life — the welding wire, part fit-up, robot programming and grounding also contribute.

Different types of contact tips: There are several types of contact tips available. Understanding the differences can help you select the best choice for your operation.

1. Copper contact tips: Contact tips made from this material are the most conductive to transfer welding current. But copper is also the softest option and will keyhole (or wear the bore unevenly) much faster. If keyholing is a pain point in your operation, this may not be the best choice. The initial cost of copper contact tips tends to be cheaper than other options.

2. Chrome-zirconium contact tips: This alloy provides better wear resistance and longer life than copper tips, holding up better to the demands and increased arc-on time of robotic welding. They are slightly less conductive than copper tips, but they are still sufficient for most robotic applications.

3. HDP contact tips: HDP tips can last 10 times longer than copper tips — and up to 30 times in some cases — depending on the application and waveform being used. Operations may be able to go from changing contact tips every two hours to only changing tips once a week. HDP contact tips are engineered to endure wear better, providing increased resistance to arc erosion in pulsed welding, as well as spray transfer and CV MIG. The precise fit between the tip and the wire also results in good arc stability to help produce high-quality welds. Because HDP contact tips reduce the impact of the welding current decline over time, they can provide a more stable and consistent arc over the life of each contact tip. These tips work best in applications that use high-quality copper-coated solid wire.

Group of three AccuLock HDP contact tips
HDP tips can last 10 times longer than copper or chrome zirconium tips — and even longer in some cases, depending on the application and waveform being used.

Common pitfalls with contact tips
Once you understand the types of contact tips available, there are numerous factors to consider when choosing the right tip for your application. Here are some common mistakes operations make when choosing contact tips so you can avoid the same pitfalls:

1. Only considering price: Many operations may look only at the price per tip when they purchase contact tips. But it’s important to look beyond the initial price and consider the big picture, which includes the downtime and labor required for changeover, along with any quality issues that may be happening in the weld cell. If a contact tip lasts three times as long, the robot can continue to weld instead of being down for a tip changeover — and there is less human interaction inside the cell .

2. Ignoring ID tolerance issues: The size and cast of the welding wire are important in making a decision about contact tips. Some tips need to be undersized for the welding wire used, while some tips need to match the wire size. And the same exact wire will vary in the necessary contact tip size depending on if the wire comes in a small spool or a 1,000-pound barrel. For most copper and chrome-zirconium tips, it’s recommended to undersize the contact tip by a single wire size when using a 500-pound barrel or greater of wire due to the wire cast. With smaller sizes of wire packaging, use contact tips that match the wire size. The goal is to maintain a clean, consistent contact between the wire and the tip so the weld current is conducted as efficiently as possible.

3. Using poor quality wire: In most cases, poor quality welding wire will lead to poor results from your contact tips. This is due to the lubrication on the wire, as well as the consistency of the wire diameter; inconsistent wire diameter wears the tip faster. Choosing a higher quality wire can improve tip life and produce better results. Also, be aware that wires without a copper coating and cored wires wear tips much faster. Using copper-coated solid wires typically slows contact tip wear.

4. Not being open to change: Some companies think the status quo is fine because they aren’t experiencing issues. They change tips in the robotic welding cell every couple of hours, even if those tips don’t need to be changed. Looking at the true length of their current tips or investing in higher-quality tips could optimize efficiency and the overall process — saving unplanned downtime and reducing the need for non-value-added labor hours.

Analyzing the robotic operation
If contact tips are being removed proactively even when there is no keyholing, burnbacks or erratic arcs, there could be potential to get more life out of contact tips.

So how can companies best analyze their robotic welding operation to determine when to change to a different type of contact tip?

Contact tips react differently to different applications, so an important first step is to run trials with varying quality levels of tips. This will provide an accurate comparison and a level set for expectations. Run each tip to failure, including the current brand, rather than proactively changing the tip on a set schedule. Be sure to log the time each part lasted. Ideally, run multiple contact tips in any trial to eliminate any outliers.

This type of trial can help to identify how much labor time is spent on tip changeovers, how much robot uptime can be achieved and what failures are occurring with each type of contact tip.

If an operation previously experienced 10 burnbacks a day and reduces that to zero by using a higher quality contact tip, this can help eliminate unplanned downtime.

Optimizing contact tip efficiency in robotic welding
It’s important to look beyond the purchase cost and consider the big picture to best evaluate the potential productivity, as well as weld quality and efficiency gains of certain contact tips. The benefits can be especially significant in robotic welding applications, where regular contact tip changeovers can be greatly reduced.

How Robotic Welding Supervisors Can Improve the Operation

How Robotic Welding Supervisors Can Improve the Operation

Gaining a good return on investment (ROI) from a robotic welding system doesn’t happen by chance. It’s a matter of optimizing the robot and the robotic welding cell to operate at peak efficiency. And while this task is a team effort, it is led by the robotic welding supervisor.

Tregaskiss fixed automatic MIG gun
Even if a robotic welding system is meeting production and quality requirements, it’s important that robotic welding supervisors commit to a continuous improvement process

So, what can the supervisor do to guide the way, while looking at more advanced considerations? Pay close attention and collaborate.

Find opportunities for improvement

Even if a robotic welding system is meeting production and quality requirements, it’s important that robotic welding supervisors commit to a continuous improvement process. Regularly looking for ways to increase efficiencies could provide the ability to produce more parts. It can also help identify issues within the robotic welding cell before they become problematic and cause downtime.

Robotic supervisors should pay close attention to details such as cable and consumable management, parts handling and workflow to pinpoint areas that could be streamlined. The goal is to avoid settling for less than optimal work practices to realize the full potential of the system. Doing so can provide companies with higher productivity and profitability and can set them apart from their competitors.

Rely on available resources

While the robotic welding supervisor may oversee the overall health of a robotic welding cell, the robot operator works hands on with the system daily to load and unload parts. For this reason, they are an excellent resource to rely on for insight into potential or existing problems, such as:

Excessive spatter
• Poor joint configurations, or
• The need for tooling adjustments

Quality technicians are another internal resource to help the robotic welding supervisor identify any issues and drive performance improvements. In conjunction with welding engineers, they can help rectify issues like overwelding or part distortion.

External sources, such as a robotic welding integrator or equipment manufacturer, can help troubleshoot and offer advice to gain efficiencies. In many cases, they can also offer ongoing training that helps everyone improve their interaction with the robotic welding cell.

This article is the second in a two-part series focused on key information welding supervisors should know to help ensure robotic welding success. Read article one, Best Practices for Robotic Welding Supervisors. 


Best Practices for Robotic Welding Supervisors

Best Practices for Robotic Welding Supervisors

With careful planning and attention to detail, companies that invest in a robotic welding system can gain advantages, such as:

Robotic MIG welding gun with AccuLock R consumables in action
It is important for welding supervisors to understand how to quickly troubleshoot issues and how to adjust the weld programs, as needed.

• Increased productivity
• High weld quality
• Cost saving
• Parts consistency

The welding supervisor managing the robotic welding cell plays a key role in achieving these results — and with some best practices in mind, can help ensure long-term success. There are some basics that provide a good starting point.

Understand the robotic welding system
To maximize uptime in a robotic welding system, welding supervisors need to look beyond the administrative and operational duties often involved with this position and consider the actual components in the system. Maintenance personnel can often help.

It’s important for welding supervisors to understand how to quickly troubleshoot issues and how to adjust the weld programs, as needed.

Having a solid understanding of the functions of the robotic welding gun, welding consumables, power cables, and their impact on quality and productivity is also important. It makes it easier to identify problems and provide the best solution.

Establish documentation and maintenance 
Keeping an accurate, detailed log of all activities in a robotic welding cell can help welding supervisors maintain control over changes that could impact performance of the robotic welding system. Information to document includes:

• The names of all employees who enter the weld cell, when they entered and why
• Parts that have been cleaned
• Consumable changes
• Drive roll tension adjustments
• Installation of a new welding wire drum

This documentation provides insight into changes in the robotic weld cell, making it easier for maintenance staff to troubleshoot any issues. It can also help the welding supervisor and maintenance personnel determine the appropriate frequency for a preventive maintenance schedule, which helps reduce unexpected downtime.

This article is the first in a two-part series focused on key information welding supervisors should know to help ensure robotic welding success. Read article two, How Robotic Welding Supervisors Can Improve the Operation.


Understanding Fixed Automatic Welding Guns

Understanding Fixed Automatic Welding Guns

Tregaskiss Fixed Automatic MIG Gun
Fixed automation welding is commonly used for welding pipes, structural beams, tanks and vessels in a shop environment prior to them being moved to the jobsite where they will be placed into service.

When it comes to automating the welding process, many companies opt for robotic welding systems due to the flexibility they provide and their ability to reach and weld multiple joints. These systems provide the advantages of speed and accuracy and can be reprogrammed to manage new projects.

But these robotic systems aren’t right for every application. In industries such as oil and gas, railcar, structural steel fabrication and shipbuilding, joint configurations are often less complex, consisting of a single part to be welded as opposed to full assemblies. In this case, fixed automatic welding is generally preferred.

About fixed automation welding

Fixed automation welding, sometimes called hard automation welding, is commonly used for welding pipes, structural beams, tanks and vessels in a shop environment prior to them being moved to the jobsite where they will be placed into service. It can also be used for welding steel plates for the general fabrication industry or in the manufacturing of hot water heaters and propane tanks.

Common Factors for Suitable Applications

One common factor in these applications is the need for either longitudinal or circular (inside or outside diameter) welds that require repeatability as opposed to versatility. Other factors that make applications suitable for fixed automation welding include:

1. A high volume of similar parts with low variety
2. Large parts with very long welds or several similar welds
3. Large parts that would be difficult to weld manually

In some cases, fixed automation welding can help companies meet high production goals at relatively low cost. And it is easy for a single operator to oversee and load parts, making it desirable from a labor perspective — particularly given the shortage of skilled welders the industry is facing.

Setups

A fixed automation welding cell can be set up in two ways. The first option requires tooling that holds the part in place, while a fixed automatic gun moves along the weld joint by way of a mechanized seam welder or a track and carriage that holds the gun in place. This option would be viable for a long structural beam, for example.

In the second scenario, the welding gun may be fixed in a single place by tooling while the part, such as a pipe, rotates on a lathe or circumferential fixture during the welding process. In today’s marketplace, there is equipment that can rotate parts in a wide range of diameters and weights.

Tooling for fixed automation welding offers minimal flexibility and can be expensive to adjust for new parts. This is true particularly in comparison to a robotic welding system that can be reprogrammed to articulate and weld in different positions along the X, Y and Z axes.

When investing in the tooling for fixed automation welding, it’s important for companies to determine upfront what their long-term applications will be. Will they continue to weld parts that are straight or circular for the foreseeable future?

Avoiding pitfalls in the process

MA1 air-cooled and MW1 water-cooled fixed automatic MIG guns with straight necks
Necks are typically available in the marketplace in varying lengths, from approximately 4 to 12 inches, and with either straight neck or 22-, 45- and 60-degree bends.

One very important part of the fixed automation welding system is the welding gun. It is not uncommon for companies to take a do-it-yourself (DIY) approach to this piece of equipment. Namely fixturing a semi-automatic gun in place with various components to mimic the performance of a fixed automatic gun. Sometimes this is done out of convenience, due to the shop having an abundance of semi-automatic guns, or because of a perceived cost savings.

Unfortunately, a DIY gun assembly for this process can be time-consuming to set up and maintain, which adversely affects productivity. It also is not optimized for fixed automation welding. Quality may suffer due to off-seam welds or other inconsistencies, leading to rework that further reduces throughput and increases costs. Also, if replacement parts are needed there could be variations in the assembly since it is not set up for this process. Again, this can lead to quality issues.

Instead, it is important to invest in a fixed automatic gun that is designed for the process. These guns have consistent components that can be sourced from manufacturers so that the welds are repeatable. And the gun manufacturers can provide service and technical support.

Looking at the choices

Guns need to be specified or customized for the application according to the available space, taking into account the distance between the gun and the part and also how far away the wire feeder is. These factors impact neck length and bend or angle, as well as cable choices.

Necks

Tregaskiss fixed automatic MIG gun with curved neck
For higher-amperage fixed automation welding applications that require longer periods of welding on thicker material, a water-cooled gun may be a good choice.

Necks are typically available in the marketplace in varying lengths, from approximately 4 to 12 inches. Available with either a straight neck or 22-, 45- and 60-degree bends. Companies need to determine the reach required to meet the weld joint, as well as the necessary angle for completing a sound weld.

Cable Lengths

Cable lengths vary from as short as 3 feet to as long as 25 feet. Longer cables are ideal for reaching a wire feeder placed further away from the part, including on a boom. In other situations, a company may mount the feeder directly on the tooling or nearby. In that case, a cableless gun is an option for air-cooled operations. These guns plug directly into the wire feeder via a power pin and do not require a cable. Amperage and duty cycle also need to be factored into the selection of a fixed automatic gun, and both depend on the thickness of the material being welded and the amount of arc-on time required.

Air-cooled fixed automatic guns are typically available from 300 to 500 amperage models, offering either 60% or 100% duty cycle. Duty cycle is defined by the amount of time within a 10-minute cycle the gun can weld without becoming overly heated.

The necks on these guns are particularly durable since they have fewer internal channels than a water-cooled gun and rely on the ambient air to cool them. They are also more resistant to bending, and replacement parts are less expensive.

For higher-amperage fixed automation welding applications that require longer periods of welding on thicker material, a water-cooled gun may be a better choice. These models are typically available in amperages ranging from 450 to 600 amps and offering 100% duty cycle.

Hybrid water-cooled guns are another option. These fixed automatic guns have a sturdy neck similar to an air-cooled model with water channels running external to it. These channels make the guns easier to maintain than water-cooled guns.

Additional considerations

Along with selecting the appropriate components for a fixed automatic gun, it’s also essential to choose high-quality consumables — nozzles, contact tips and gas diffusers. This helps minimize downtime for frequent changeovers and supports production goals. They can also reduce quality issues that could require rework later in the welding operation.

Consumables are available that can be used across different types of welding guns, including semi-automatic ones and fixed automatic guns. This compatibility can be beneficial to simplifying inventory and preventing errors when installing new consumables on either type of gun.

How to Prevent Common Causes of Poor Welding Wire Feeding

How to Prevent Common Causes of Poor Welding Wire Feeding

Poor wire feeding is a common problem encountered in many welding operations. Unfortunately, it can be a significant source of downtime and lost productivity — not to mention cost.

Poor or erratic wire feeding can lead to premature failure of consumables, burnbacks, bird-nesting and more. To simplify troubleshooting, it’s best to look for issues in the wire feeder first and move toward the front of the gun to the consumables.

Finding the cause of the problem can sometimes be complicated, however, wire feeding issues often have simple solutions.

What’s happening with the feeder?

Image of welder with semi-automatic MIG gun welding
Finding the cause of poor wire feeding can sometimes be complicated, however, the issue often has simple solutions.

When poor wire feeding occurs, it can be related to several components in the wire feeder.

1. If the drive rolls don’t move when you pull the trigger, check to see if the relay is broken. Contact your feeder manufacturer for assistance if you suspect this is the issue. A faulty control lead is another possible cause. You can test the control lead with a multimeter to determine if a new cable is needed.

2. An incorrectly installed guide tube and/or the wrong wire guide diameter may be the culprit. The guide tube sits between the power pin and the drive rolls to keep the wire feeding smoothly from the drive rolls into the gun. Always use the proper size guide tube, adjust the guides as close to the drive rolls as possible and eliminate any gaps in the wire path.

3. Look for poor connections if your MIG gun has an adapter that connects the gun to the feeder. Check the adapter with a multimeter and replace it if it’s malfunctioning.

Take a look at the drive rolls

Image of welding wire bird-nesting in drive rolls
Bird-nesting, shown here, can result when the liner is cut too short or the liner
is the wrong size for the wire being used.

Using the wrong size or style of welding drive rolls can cause poor wire feeding. Here are some tips to avoid problems.

1. Always match the drive roll size to the wire diameter.

2. Inspect drive rolls every time you put a new spool of wire on the wire feeder. Replace as necessary.

3. Choose the style of drive roll based on the wire you are using. For example, smooth welding drive rolls are good for welding with solid wire, whereas U-shaped ones are better for tubular wires — flux-cored or metal-cored.

4. Set the proper drive roll tension so there is sufficient pressure on the welding wire to feed it through smoothly.

Check the liner

Several issues with the welding liner can lead to erratic wire feeding, as well as burnbacks and bird-nesting.

1. Be sure the liner is trimmed to the correct length. When you install and trim the liner, lay the gun flat, making certain the cable is straight. Using a liner gauge is helpful. There are also consumable systems available with liners that don’t require measuring. They lock and concentrically align between the contact tip and power pin without fasteners. These systems provide error-proof liner replacement to eliminate wire feeding problems.

2. Using the wrong size welding liner for the welding wire often leads to wire feeding problems. Select a liner that is slightly larger than the diameter of the wire, as it allows the wire to feed smoothly. If the liner is too narrow, it will be difficult to feed, resulting in wire breakage or bird-nesting.

3. Debris buildup in the liner can impede wire feeding. It can result from using the wrong welding drive roll type, leading to wire shavings in the liner. Microarcing can also create small weld deposits inside the liner. Replace the welding liner when buildup results in erratic wire feeding. You can also blow compressed air through the cable to remove dirt and debris when you change over the liner.

Image of contact tip burnback
Close up of a wire burnback in a contact tip on a self-shielded FCAW gun. Inspect contact tips regularly for wear, dirt and debris to help prevent burnback (shown here) and replace contact tips as necessary.

Monitor for contact tip wear

Welding consumables are a small part of the MIG gun, but they can affect wire feeding — particularly the contact tip. To avoid problems:

1. Visually inspect the contact tip for wear on a regular basis and replace as necessary. Look for signs of keyholing, which occurs when the bore in the contact tip becomes oblong over time due to the wire feeding through it. Also look for spatter buildup, as this can cause burnbacks and poor wire feeding.

2. Consider increasing or decreasing the size of contact tip you are using. Try going down one size first, which can help promote better control of the arc and better feeding.

Additional thoughts

Poor wire feeding can be a frustrating occurrence in your welding operation — but it doesn’t have to slow you down for long. If you still experience problems after inspecting and making adjustments from the feeder forward, take a look at your MIG gun. It is best to use the shortest cable possible that can still get the job done. Shorter cables minimize coiling that could lead to wire feeding issues. Remember to keep the cable as straight as possible during welding, too. Combined with some solid troubleshooting skills, the right gun can keep you welding for longer.

    AccuLock R Consumables Reduce Downtime in Robotic Welding

    AccuLock R Consumables Reduce Downtime in Robotic Welding

    In many cases, equipment-based solutions can be a means to gain success in the robotic welding operation. They can mitigate costly risks and eliminate issues that lead to inefficiencies. And often, these issues are related to a small but significant part of the robotic welding process — the welding consumables.

    Robotic welding gun live welding with AccuLock R Consumables
    The right welding consumables can help mitigate costly risks and eliminate issues that lead to inefficiencies in the robotic welding operation.

    Changing over consumables can be a time-consuming part of maintaining the welding cell, especially if it is done multiple times during a shift. Changeover can also negatively impact productivity and quality if the consumables are installed incorrectly. Unfortunately, given the industry’s current lack of skilled welders, that may be a common occurrence. Welders simply have less experience with proper installation processes. To address this problem, many companies tend to spend more time and money on training and troubleshooting. They may even have to find workarounds to problems in the weld cell as employees get up to speed. All of this occupies resources.

    Consumable challenges

    Welding consumables — the contact tip, gas diffuser and nozzle — can be a major source of downtime in robotic welding operations, unplanned or planned.

    During installation, cross-threading of contact tips by less experienced welders is a common occurrence that can result in unplanned downtime. Cross-threading leads to multiple problems beyond the lost productivity for contact tip changeover.

    First, it can negatively affect tool center point (TCP), causing the robot to weld off-seam and create quality issues like lack of fusion or poor penetration. Personnel overlooking the robotic welding cell then need to stop production to address rework and/or scrap the part.

    Cross-threading can also create a keyhole, or uneven wear, in the bore of the contact tip. A keyhole the size of only half the diameter of the wire can result in the robot welding off-seam.

    AccuLock R Consumables
    Tregaskiss® AccuLock™ R consumables are designed to support higher throughput, provide a long service life and ensure good weld quality.

    Many times, a cross-threaded contact tip will stick inside the welding gas diffuser. Without another gas diffuser readily available, the operator has to make a trip to the tool crib for a new one. Meanwhile the robot is offline and not producing parts. Plus, a company incurs costs for both the contact tip and the diffuser’s replacement.

    Companies that invest in power sources with a pulsed waveform capability — particularly in the automotive industry — often schedule planned downtime. Pulse waveforms improve productivity and quality by increasing travel speeds, providing a more consistent arc and reducing spatter. However, the pulsing action of the arc electrically and mechanically erodes the contact tip, leading to faster wear. It is necessary to plan downtime as a preemptive strike against contact tip failures before the chance of associated weld quality issues arise.

    Both unplanned and planned downtime cost money and occupy available labor for non-value-added activities — tasks that don’t support throughput and productivity.

    There is a new welding consumables technology that can help.

    A new consumables solution

    To address the issue of cross-threaded contact tips, Tregaskiss designed its AccuLock™ R consumables. The design is intended to support higher throughput, provide a long service life and ensure good weld quality.

    The AccuLock contact tip features a long tail that concentrically aligns within the diffuser before the threads engage. The threads are also coarse, so they require minimal rotations to install. This design virtually eliminates the risk of cross-threading and provides three key benefits to the robotic welding operation:

    1. It decreases the length of unplanned downtime for retrieving a replacement welding gas diffuser after cross-threading.
    2. It reduces quality issues from cross-threading, such as off-seam welds or poor joint penetration.
    3. It lessens unplanned downtime for troubleshooting.
    This cutaway shows how the long tail on the AccuLock R contact tip concentrically aligns within the diffuser before the threads engage. The threads are also coarse, so they require minimal rotations to install.

    The contact tips also have greater mass at the front compared to other designs, along with a taper that mates securely with the gas diffuser. The tapered surfaces ensure optimal conductivity, reduce heat and keep the consumables locked in place. These features — combined with the fact that 60% of the contact tip is buried in the diffuser, away from the heat of the arc — make the consumables last longer. Extending the product life means there is less need for changeovers.

    AccuLock R consumables can also address the accelerated wear of contact tips caused by pulsed waveforms. In addition to offering the contact tips in copper and chrome zirconium, Tregaskiss has an AccuLock HDP option. The HDP contact tips last more than 10 times longer than copper tips in pulsed MIG welding applications. As a result, companies can reduce unplanned downtime for contact tip changeover — and make those changeovers faster because of the easy-to-install design.

    AccuLock Contact Tips
    In addition to offering the contact tips in copper and chrome zirconium, Tregaskiss has an AccuLock HDP option. The HDP contact tips last at least 10 times longer than copper tips in pulsed MIG welding applications.

    AccuLock R consumables can be implemented easily. Switching from many other consumables typically doesn’t affect TCP or robotic programming; however, it is best to consult directly with Tregaskiss to confirm this is the case.

    For companies that have both robotic welding and semi-automatic welding operations, the AccuLock R consumables can simplify complex inventories. The contact tips are part of a Common Consumable Platform™ and can be used across a wide range of Tregaskiss® robotic and fixed automatic MIG guns, as well as with Bernard® semi-automatic MIG guns (ranging from 200 to 600 amps). This common contact tip can reduce inventory costs and lessens the opportunity for operators to install the wrong consumable. The AccuLock R gas diffuser also has a blue o-ring to distinguish it from other diffusers.

    Making the change

    When companies find equipment solutions, like the AccuLock R consumables, that help reduce troubleshooting and downtime in their robotic welding operations, opportunities can increase. The ability to improve productivity and quality is at the forefront of those. But there may also be more time available to optimize the weld cell, make positive changes to workflow or material handling and seek out cost savings.In some cases, companies may also uncover issues in the weld cell that were previously masked by frequent contact tip changeovers. Now, however, there is more time address those to generate greater efficiencies in the operation.

    In short, with the right consumables, there is more time to focus on reaching improvement targets and increasing throughput — and on implementing training that can help achieve those goals.

      How to Successfully Implement a Robotic Welding System

      How to Successfully Implement a Robotic Welding System

      In today’s marketplace, companies continue to automate portions, if not all of their welding operation. The reasons are many: to address a shortage of skilled labour, to improve quality, to decrease waste and rework, and/or to increase productivity — in short, to seek benefits that provide a competitive edge.

      Not all companies, however, are successful in the process. Those beginning without a well-thought-out roadmap risk losing valuable time during implementation and operation and may miss the full benefits provided by a robotic welding system.

      Conversely, companies that begin with a careful examination of their welding needs and existing processes — and develop a detailed plan with clearly established goals — are more likely to achieve success. Planning should include an accurate assessment of parts, work flow and the current facility, as well as an evaluation of the potential return on investment (ROI).

      Companies should not only look at current needs, but also consider future opportunities to determine the best robotic welding system to scale for potential growth or changes to products they may produce later.

      Image of a robotic operator with a teach pendant by a robotic MIG welding cell
      Companies need a welding operator or other employee skilled in robotic welding programming. This will likely involve additional training to upgrade his or her skill sets.

      Why robotic welding?

      In an economy where orders are increasing and welding positions are hard to fill, robotic welding can help maintain or increase productivity. In a semi-automatic welding operation, labour accounts for approximately 70 to 85% of the total cost of welding a part. A robotic welding system can reduce that cost and increase throughput by completing the work of two to four people in the same amount of time — however, companies still require skilled welding operators to oversee the robotic cell.
      In addition, the national and international marketplace has become increasingly competitive, with companies seeking contracts from any number and any size of business. Investing in welding automation can help set up a company on the path to compete at a global level.

      Here are additional benefits:

      1. With the right robotic welding system, companies can improve first-pass weld quality and reduce the amount of rework or scrap parts. Depending on the welding wire and mode used, the system may also minimize or eliminate spatter, which reduces the need to apply anti-spatter compound or perform post-weld clean up.

      2. A robotic welding system can reduce over-welding, a common and costly occurrence associated with the semi-automatic process. For example, if a company has welding operators who weld a bead that is 1/8-inch too large on every pass, it can potentially double the cost of welding (both for labour and for filler metals). Over-welding may also adversely affect the integrity of the part.

      3. Companies can reallocate skilled employees to other production areas to fill open positions and gain additional productivity and efficiencies.

      4. Welding automation can also provide a competitive advantage as it may be considered attractive to customers. The improvement in quality may prompt new customers to place orders or lead existing customers to increase their orders with the objective of growing their own businesses.

      5. Finally, robots are fast. They don’t have to weld all day to be profitable. That fact improves productivity and the bottom line by making the same number of parts as in a semi-automatic process in less time.

      Repeatability is key

      When considering an investment in a robotic welding cell, companies should have part blueprints, preferably in an electronic format. Without a blueprint, the part likely won’t meet the basic criterion necessary to ensure repeatability during the manufacturing process.

      A robotic welding system welds in the same place every time. When a part’s tolerances are unable to hold its position — if there are gap and/or fit-up issues — the company will simply be automating a broken process. This can increase rework or scrap.

      If a company currently relies on its welding operators to compensate for fit-up issues, it will need to look upstream in the manufacturing process to establish consistency. What processes need to change so these welding operators send uniform parts downstream? Or, if vendors supply the parts, can they guarantee consistency?

      Assess the workflow

      A streamlined workflow is one of robotic welding’s benefits. To achieve it, companies need to look beyond the weld cell, making certain the facility can accommodate a smooth flow of materials. It makes little sense, for example, to invest in a robotic welding system to increase productivity, but then place it in a corner where employees may have to handle each part multiple times.

      There should be a consistent supply of parts to avoid moving a bottleneck from one area to another. It is also important to look at the expected cycle time of the robot. Can personnel supply parts to keep up with the demand of the robot’s cycle time? If not, the supply of parts, including where the company stores them and how it moves them, will need to be adjusted. Otherwise, a robot will sit idle waiting for components to come down the line.

      Image of a robotic welding application with sparks
      A streamlined workflow is one of robotic welding’s benefits. To achieve it, companies need to look beyond the weld cell, making certain the facility can accommodate a smooth flow of materials.

      Robotics or fixed automation?

      There is no single welding automation solution that is best for every company. When a company is considering the investment, it should factor in the expected lifetime of the job, the cost of tooling and the flexibility the equipment offers.

      Fixed automation is the most efficient and cost-effective way to weld parts with simple, repetitive, straight welds or round welds, where the part is rotated with a positioner. If a company wants to reuse the equipment when the current job ends, however, a robotic welding system offers more flexibility. A single robot can store programs for multiple jobs, so it may be able to handle the tasks of several fixed-automation systems.

      There is a certain volume of parts that justify the investment of welding automation for each company. An accurate assessment of goals and workflow can help determine what that volume is. If a company makes only small runs of parts, robotic welding becomes more challenging. But, if a company can identify two or three components that can be automated, a robot can be programmed to manufacture those parts, offering greater versatility and boosting productivity. This may benefit even small companies that may not have significant volume of a single part.

      Although a robot is more expensive than a fixed-automation system, it is important to consider the cost of the tooling before deciding between the two. Fixed automation systems can become quite expensive if they require extensive changes to retool a new part so it can be welded consistently.

      Consider the available space

      The physical footprint for a robotic welding system and the area needed for parts to flow into the welding cell is typically greater than that of a semi-automatic welding operation. The available space needs to be adequate for the robot, welding power source and other equipment. This helps minimize the need to customize products, such as cables, nozzle cleaning stations (or reamers) or the robotic MIG gun to fit the work envelope.

      A company with less space can still make welding automation work. One option is to purchase fewer pieces of robotic welding equipment that are capable of performing multiple tasks, such as material handling or vision/scanning systems.

      A third-party integrator can help determine whether a facility suits the installation of a robotic welding system. System integrators are knowledgeable about facility modifications, including important safety regulations that apply in a company’s region, country or state — in addition to those specified by OSHA and RIA (Robotic Industries Association).

      Integrators and equipment selection

      In addition to offering advice on facility modifications and helping a company select the right robot, a robotic systems integrator or welding automation specialist can:

      1. Help determine if parts are suitable for automation, and, if not, what is required to make them suitable

      2. Analyze the workflow and facility to identify potential roadblocks

      3. Analyze the true costs involved with the investment, including facility updates and tooling

      4. Determine the potential payback of the investment

      5. Help identify goals and develop a precise plan and timetable to achieve those goals

      6. Explain automation options and help select those that best fit the company’s needs

      7. Help select a welding equipment that has the flexibility to maximize travel speed, minimize spatter, eliminate over-welding, provide great arc stability and increase first-pass weld quality

      Robotic application with canvas
      With the right robotic welding system, companies can improve first-pass weld quality and reduce the amount of rework or scrap parts.

      Integrators can also help select additional equipment for the robotic welding cell, including positioners, tooling, the robotic MIG gun, welding wire and peripherals. Each item serves a distinct function.

      The positioner turns, rotates or otherwise moves the part into an optimal position for welding. In many cases, this involves moving the part so that the system can weld in a flat position for optimal deposition efficiency. A positioner can also allow for coordinated motion between the robot and weldment.

      The tooling holds the part in place during welding and is a critical component of a robotic welding system. The robot arm and robotic MIG gun travel a programmed path each cycle. If the weld joint is out of place because the part is misaligned, it can result in inadequate fusion or penetration and rework or scrap. It is important to design the tooling correctly upfront when investing in a robotic welding cell and monitor it for mechanical wear or heat distortion once it has been put into operation. This helps ensure consistent part fit up so that weld quality doesn’t suffer.

      Tregasskiss Automatic application
      Most robot OEMs offer a weeklong training course explaining how to operate the equipment. This course, followed by a week of advanced programming, is recommended when implementing welding automation.

      The robotic MIG gun should never be an afterthought when considering an investment in welding automation, nor should the welding wire. Both can have a significant impact on productivity and profitability. An integrator can help with the selection based on how the gun and wire perform in conjunction with the rest of the system’s components. The gun will be subject to intense heat and spatter, so it must be durable. It also needs to be the appropriate size to maneuver around the tooling and gain proper joint access.

      Finally, peripherals, such as reamers, an anti-spatter sprayer and wire cutter are good options to discuss with an integrator prior to making the investment in welding automation. These devices can improve uptime and welding performance by keeping the welding gun consumables free of spatter, operators out of the weld cell and providing consistent wire stickout during welding.

      Employee training

      Companies cannot simply purchase a robotic welding system and let it go. They need a welding operator or other employee skilled in robotic welding programming. This will likely involve additional training to upgrade his or her skill sets. The good news is, programming a robot today is much quicker than in the past. Simplified teach pendants, along with the availability of desktop programming, help expedite the process and reduce downtime. Despite the ease of programming, however, companies may need to alleviate some existing tasks to allow time for the employee to oversee the robotic welding cell without becoming overloaded with too many responsibilities.

      Most robot OEMs offer a weeklong training course explaining how to operate the equipment. This course, followed by a week of advanced programming, is recommended when implementing welding automation.

      Justifying the expense and calculating payback

      If the personnel investigating the prospect of robotic welding determine it’s a good fit, they will likely need to justify the investment to upper management or an owner. Calculating the potential payback is essential. There are several steps to consider.

      First, determine whether the volume of parts the company needs to produce requires the speed of welding automation. Remember, the key benefit of a robotic welding system is the ability to produce high volumes of quality welds or in smaller facilities to offer the flexibility to weld smaller volumes of multiple parts.

      Calculate payback by assessing the current volume of semi-automatic parts and cycle times. Compare these to the potential cycle times of a robotic welding system. Again, an integrator or welding automation specialist can help. Establishing the comparison is critical to estimating the potential return on investment.

      That said, even if a company will produce the same number of parts with a robot, it could justify the investment by the amount of labour it can reallocate elsewhere in the operation for jobs that boost production, eliminate bottlenecks or increase quality. For example, a company could utilize the skills of semi-automatic welding operators to complete challenging welds that are too complicated for a robot to manage.

      It’s important to factor the bulk cost of shielding gas and welding wire when looking at the potential payback. While there is an initial cost for a shielding gas/manifold system, it can help optimize a company’s robotic welding capabilities in the long term by minimizing downtime for cylinder changeover. The same is true for welding wires. The larger drums — typically ranging from 500 to 1500 pounds — can further reduce costs in a robotic welding cell since they require fewer changeovers and often come with purchasing discounts.

      Companies need to keep in mind that the benefits of robotic welding can be significant. However, those benefits come at an upfront price. Many companies, especially smaller ones or those that frequently change production lines, need a faster payback — no more than 12 to 15 months is common to justify the investment. If a company will have the same production needs for many years, it can typically justify a longer payback period. Management and owners should discuss their payback goals with a trusted robotic welding integrator as part of the assessment process. 


        Improving Welding Automation Safety With Risk Assessment and Training

        Improving Welding Automation Safety With Risk Assessment and Training

        Robotic welding systems continue to gain in popularity due to their ability to increase productivity, improve quality and decrease costs in the right application. But they also offer a way to address a shortage of skilled labor for manual operations. Welding automation provide companies with a means of staying competitive in a demanding marketplace, while using their existing and potential workforce to oversee the weld cell.

        With more and more robotic welding systems being implemented — the Robotics Industries Association (RIA) cited that 20% of all industrial applications had robotic welding cells as of 2017 — comes the need for increased attention to safety. From the robotic welding gun and peripherals to the robot itself, following safety best practices is essential. 

        Robotic welding safety hazards and resources

        Image of robotic welding with sparks
        Welding automation offers companies a means of staying competitive in a demanding marketplace while using their existing and potential workforce to oversee the weld cell.

        Statistically, welding automation is safer than manual or semi-automatic welding. However, operators overseeing the robotic welding cell must still remain vigilant. This is particularly true when performing nonstandard operations; these include programming, maintenance and any other tasks that involve direct human interaction with the robot. 

        Conducting a thorough welding risk assessment helps identify potential safety hazards associated with a specific robotic welding system (whether it is a pre-engineered or custom cell) and is a critical first step in establishing a safer welding environment. This assessment provides a baseline for implementing solutions for identified risks and establishing appropriate welding safety training. In addition, it helps companies maintain compliance with safety standards, which most importantly protects employees but also protects the bottom line. Noncompliance and/or safety violations that can lead to injury become can be costly in terms of fines and workers’ compensation. 

        External Resources

        Companies can obtain welding safety resources through the American Welding Society (AWS), including Safety in Welding, Cutting, and Allied Processes, ANSI Standard Z49.1, a free download at aws.org. The National Fire and Protection Association (NFPA) also offers resources. RIA follows American National Standards Institute (ANSI) standards and offers safety seminars and webinars. RIA also provides information on industrial machinery and guarding, as well as guidelines to help companies, including the American National Standard for Industrial Robots and Robot Systems – Safety Requirements, ANSI/RIA R15.06-2012. The Occupational Safety and Health Administration (OSHA) is another valuable safety resource.

        Image of MIG gun in robotic welding cell
        A built-in awareness barrier in pre-engineered cells is another means of aiding operator safety. This hooped (yellow) barrier inside the weld cell covers the sweep area of the indexing table.

        Many robotic welding integrators or robotic welding system manufacturers offer training for the safe use of their equipment, including how to test safety functions and at what frequency. They also provide manuals and safety standards for their systems. It is critical to read and follow these thoroughly.

        Safe use of robotic welding guns, consumables and reamers

        Manufacturers of robotic MIG welding guns often integrate design elements into these products to aid in their safe use. These elements are intended to protect operators during routine maintenance and minimize or eliminate the need to enter the weld cell to complete tasks.

        For example, guns that are compatible with front-loading liners help improve safety in a robotic welding cell. These liners can be installed from outside the weld cell — there is no need to climb over tooling or maneuver around the robot to complete replacement. Operators or maintenance personnel also don’t need to remove electrical connections to replace components during the process.

        An insulating disc is another important safety feature in select guns. It helps protect operators from the welding current during maintenance and protects the robot from the current, limiting potential damage.

        In addition to integrated safety features, there are some key best practices for working with robotic welding guns, consumables and reamers (or nozzle cleaning stations). First and foremost, always de-energize the robotic welding system when installing a robotic MIG gun or consumables, and follow all lockout/tagout procedures.

        When possible, it’s ideal to have a window or opening that allows consumables to be changed or inspected from outside the weld cell.

        When possible, it’s ideal to have a window or opening that allows consumables to be changed or inspected from outside the weld cell. If this isn’t feasible, programming the robot to stop near the weld cell door simplifies consumable changeover and eliminates the need for the operator to enter the cell, maneuver around tooling or climb on anything to complete the job.

        Personal Protective Equipment (PPE)

        The appropriate personal protective equipment (PPE) is also important when changing over consumables or the welding wire. The nozzle and contact tip may be hot, and there is the risk of the welding wire puncturing the operator. Leather or other thick work gloves are a must, and safety glasses should be worn at all times. Always use the proper tool to change over the nozzle and contact tip. We recommend a pair of welpers.

        When performing maintenance on a reamer, begin by resetting the equipment to a home state, de-energizing it and following lockout/tagout procedures. Be certain there is no supply of air or electricity to the reamer. When changing over cutter blades, always wear gloves and use two wrenches to remove and install them. Reset the reamer to a home state when finished. This is an important last step, as the reamer will automatically complete a cycle as soon as it receives a start signal and is reenergized.

        Image of a robotic operator with a teach pendant by a robotic MIG welding cell
        Some pre-engineered welding cells feature sliding programming access doors with magnetic keys that indicate that they are fully open and ready to be locked out prior to maintenance, helping to prevent pinch points or a trap hazard.

        Navigating the robotic welding cell safely

        Welding operators and maintenance personnel should familiarize themselves with the emergency stops on a robotic welding system as a first safety step. The number and location of these stops varies by system. For example, welding cells typically have an operator station emergency stop that ceases all robot functions and turns off the robot servo power, along with an emergency stop on the teach pendant. Operators should test these emergency stops periodically, although testing too frequently is stressful on the mechanics of the robotic welding system.

        Understanding brake release procedures is also critical. RIA sets standard requirements for these; however, every robotic welding system is different, and the location of the override buttons may vary.

        As when interacting with a robotic MIG welding gun, consumables or reamer, always follow proper lockout/tagout procedures before entering the robotic welding cell. Many systems have multiple lockout/tagout locations that are indicated by stickers. Some pre-engineered welding cells feature sliding programming access doors with magnetic keys that indicate that they are fully open and ready to be locked out prior to maintenance, helping to prevent pinch points or a trap hazard.

        Image of Tregaskiss TOUGH GUN CA3 robotic MIG gun with 45 degree neck
        Manufacturers of robotic MIG welding guns often integrate design elements into these products to aid in their safe use.

        A built-in awareness barrier in pre-engineered cells is another means of aiding operator safety. This hooped barrier inside the weld cell covers the sweep area of the indexing table. Its purpose is to protect the operator from pinch points during teaching operations by separating the him or her from the space between the robot and the wall of the weld cell.

        Unenclosed Robotic Systems

        For robotic systems that are not enclosed, guards around the cell are necessary. These can take the form of physical barriers, like perimeter fencing or light curtains and/or electronic guarding such as area scanners that stop the robot when an operator is present in a specific area of the system.

        Lastly, robotic integrators and robotic welding system manufacturers provide risk assessment documentation, typically in the operator’s manual. It is important to review this assessment thoroughly and train employees on the proper techniques to mitigate any identified risks. For example, programming the robot introduces mechanical hazards such as the potential for pinching or impact, which can be addressed by standing a safe distance outside of the weld cell or by using a slower teach speed if offered on the teach pendant.

        Other safety considerations

        In addition to the best practices outlined for robotic MIG welding guns, consumables and systems, there are steps to further protect employees.

        • Be certain the robotic welding cell is clean and clear of any debris, tools or other items that could create a hazard during welding.
        • Avoid wearing loose clothing or jewelry when interacting with the robot.
        • Operators should wear a bump cap as head protection when entering the weld cell for inspection or maintenance.
        • Anti-spatter liquid can settle on the floor, making it slick. Clean the floor as needed to help prevent slipping hazards. 

        Creating a culture of safety

        Safety in welding automation should be top of mind among operators, management and maintenance personnel. Ongoing training needs to be a priority, whether it is conducted through company programs or seminars offered by outside resources. The goal is to ensure that everyone involved with the robotic welding system is playing an active role in employing best practices. When following them properly, the result is a safer work environment and a stronger bottom line.

          Selecting the Right MIG Welding Consumables

          Selecting the Right MIG Welding Consumables

          MIG welding gun configurators, like the Bernard® BTB semi-automatic air-cooled MIG gun configurator, allow you to choose specific styles or types of consumables to match the demands (amperages and waveforms) of your application.

          Image of AccuLock S MIG gun consumables including liner, nozzle, contact tip and diffuser

          Selecting contact tips

          Know the wire size and type when choosing the size and style of contact tip.

          1. Contact tips with coarse threads help speed replacement since they require less turns and they minimize cross-threading.
          2. Some consumable systems also feature a contact tip that is buried in the gas diffuser. This keeps it cooler and helps it last longer.
          3. For more aggressive welding waveforms, like pulsed MIG welding, choose a more durable contact tip. Chrome zirconium is a good option.

          Welding nozzle options

          Joint access, operating temperatures and arc-on time are important considerations in choosing the right welding nozzle.

          1. Brass nozzles are good for reducing the spatter adhesion in lower amperage applications, but do not perform well at higher temperatures.
          2. Copper nozzles are a better choice for higher amperage applications.

          MIG gun liner selection

          Having the right MIG gun liner helps minimize downtime to address wire feeding issues. It is important that you always trim the liner to the proper length. Consider these tips:

          1. Liners are available that require no measurement for error-proof replacement. These liners lock and concentrically align to the contact tip and the power pin without the use of fasteners for smooth wire feeding.
          2. When the weld cell has a wire feeder mounted on a boom, front-loading liners help make changing liners faster, easier and safer by eliminating the need to climb up to the feeder.
          3. Specialty liners can aid in the feedability of the wire, especially in metal-cored or flux-cored applications.

          Note, selecting the same welding consumables across multiple weld cells, when possible, can help with inventory management and can be more cost-effective.

          Visit the Bernard® MIG gun configurators


          This article is the third in a three-part series discussing how configuring a MIG gun can improve the welding operation, as well as what to consider in the process. Read article one, Configuring a MIG Welding Gun for Your Application and article two, How to Choose MIG Welding Gun Parts.

            How to Choose MIG Welding Gun Parts

            How to Choose MIG Welding Gun Parts

            In addition to the amperage of MIG welding gun you choose, the MIG gun parts — cable, neck and handle — affect how comfortably and efficiently you can weld. Configure your gun accordingly.

            Image of live welding with semi-auto MIG gun

            Choosing the cable

            Cable lengths can vary greatly — from 10 feet to 25 feet or longer. Use the shortest cable possible that can get the job done to prevent kinking or creating a tripping hazard. Consider your options:

            1. Industrial-grade cables are the most commonly used and work well in light- to medium-duty applications.
            2. Steel mono-coil cables are well-suited for heavy-duty applications in harsh environments. They are more rigid, which minimizes feeding issues when using a longer cable.

            Remember, smaller welding wire sizes typically call for a shorter cable; it is more difficult to push a smaller wire over a greater length. It is also more difficult to push soft wires, like aluminum, through longer cables.

            MIG welding gun necks and handles

            Choosing a neck and handle for a MIG welding gun comes down to your preference, as well as the available weld cell space and the welding wire.

            1. Neck options are available with bends ranging from 30 degrees up to 80 degrees. Those with less bend reduce bird nesting or other feeding issues associated with thicker wires and softer wires.
            2. A rotatable neck makes it easier to change angles to access the weld joint.
            3. Gun handles are available in straight or curved options. Straight handles are often paired with fixed necks, while curved handles are often paired with rotatable necks.

            The bottom line: Choose the options that make it easiest and most comfortable for you to reach the weld joint.

            Configure a Bernard® semi-automatic MIG gun
             

            This article is the second in a three-part series discussing how configuring a MIG gun can improve the welding operation, as well as what to consider in the process. Read article one, Configuring a MIG Welding Gun for Your Application and article three, Selecting the Right MIG Welding Consumables.  

              Configuring a MIG Welding Gun for Your Application

              Configuring a MIG Welding Gun for Your Application

              Have you struggled to gain proper joint access when welding? Or found yourself fatigued at the end of the day because of repeatedly welding in awkward positions? Configuring a MIG welding gun can help.

              Why configure?

              Image showing three different hand-held BTB MIG guns

              A MIG welding gun configured for the exact application can maximize efficiency and productivity. When you are more comfortable, you are able to weld longer. A customized MIG welding gun also reduces downtime for assembly, since it’s ready right out of the box. You can configure each welding gun part with online configurators like those from Bernard. These parts include the:

              • Cable
              • Handle and trigger
              • Neck type, angle and length
              • Consumables
              • Power pin
              • Liner

              How do you get started?

              To configure the right MIG welding gun, look at the needs of your welding application. One answer influences the next choice.

              1. Determine the type and thickness of the base material on which you typically weld. This will dictate the welding wire selection and welding parameters, and in turn the amperage of MIG welding gun needed.
              2. Think about the expected arc-on time and length of the welds. Again, this impacts the amperage needed and also the duty cycle.
              3. Consider ergonomics. Decide what handle and neck style you prefer, as well as the cable length needed (shorter ones are lighter and easier to maneuver).

              What affect does the weld cell have?

              The physical space of the weld cell factors into MIG welding gun configuration. Consider these factors:

              1. If there are fixtures or jigs to work around, you may need narrower MIG welding consumables to access the joint.
              2. Space limitations and welding position impact cable length. Shorter cables are necessary for confined areas and are best for repetitive welding at a table since they are lighter. For out-of-position welds, a longer cable allows for greater movement (beware of coiling or kinking).
              3. The available workspace and joint access affect the length and bend angle of the gun neck you can use.

              Taking the time to consider the factors that impact how you configure your MIG welding gun can go far in ensuring you have the exact one for your application.

              See options for configuring a Bernard® MIG gun

              This article is the first in a three-part series discussing how configuring a MIG gun can improve the welding operation, as well as what to consider in the process. Read article two, How to Choose Welding Gun Parts, and article three, Selecting the Right MIG Welding Consumables.
               

                Common Problems With MIG Welding Consumables and How to Fix Them

                Common Problems With MIG Welding Consumables and How to Fix Them

                MIG welding consumables are a critical but often overlooked part of the welding operation. Unfortunately, without a clear understanding of the problems that can arise with consumables — and the best way to fix them — companies stand to lose productivity, jeopardize quality and increase costs. In some cases, the biggest issue is choosing the wrong consumable for the job.

                Consider this real-life example: A company with 90 arcs is using five contact tips per day, per welder — that adds up to 450 contact tips a day. By simply changing to a more robust consumable system, the company could potentially use one contact tip per welder every three to four days. The savings in reduced downtime and purchasing costs in this situation is significant.

                Image of welder, welding in a semi-automatic application
                Paying close attention to MIG gun consumables is important to gaining good welding performance.

                So how can companies avoid common pitfalls? A willingness to look at the impact of welding consumables on the overall operation — not just the product purchase price — is key. Training is also a vital part of success. Welding operators and maintenance personnel should know how to properly select, install and maintain consumables and troubleshoot problems when they arise. Or better yet, understand how to prevent them in the first place.

                Making sense of welding nozzles

                Welding nozzles play an important role in the welding operation, directing shielding gas to the weld pool to protect it from contaminants.

                Incorrect contact tip recess within the welding nozzle is among the biggest problems. The more the contact tip is recessed, the longer the wire stickout, which can lead to an erratic arc and increased spatter in the nozzle. It can also negatively impact shielding gas coverage.

                In approximately 90% of applications, a 1/8-inch contact tip recess provides the best shielding gas coverage with a welding wire stickout that helps support consistent arc stability.

                Using the wrong welding nozzle for the application can cause downtime for changeover due to premature failure. For a standard welding application (100 to 300 amps), a copper nozzle provides good heat resistance. Copper nozzles also resist spatter buildup. For higher-amperage applications (above 300 amps), a brass welding nozzle is the better choice. Brass does not anneal as fast as copper, so the welding nozzle will maintain its hardness longer under higher temperatures.

                Choosing the wrong shape and size of nozzle can be problematic. Too large of a nozzle can make it difficult to obtain the joint access needed to complete a sound weld.

                Long or short tapered nozzles work well for restricted joints. However, there is an increased risk of spatter buildup due to the narrower bore, which can shorten the consumable’s life. To gain good gas coverage, use a longer nozzle when possible.

                Image of a welder in a semi-automatic application
                Welding operators and maintenance personnel should know how to properly select, install and maintain consumables and troubleshoot problems when they arise.

                Avoiding contact tip downfalls

                MIG welding contact tips provide the current transfer to the welding wire to create an arc.

                Using a contact tip with an inside diameter (ID) that’s too small can lead to poor wire feeding and, potentially, a burnback. Using a tip with too large of an ID can cause the welding wire and arc to wander.

                Every consumables manufacturer has proprietary formulas for gauging contact tip ID and implementing it into their design. Select a high-quality contact tip for consistent tolerances, and match the contact tip ID to the diameter of the welding wire to gain the best electrical conductivity. This happens because the contact tip ID is actually slightly larger than the specified measurement. For example, pairing a contact tip with an ID of 0.035 inch and a wire with the same diameter allows the wire to feed smoothly through the bore, connecting enough to generate a stable welding arc.

                The wrong contact tip outside diameter (OD) can also cause problems. For higher amperage applications, use a contact tip with a larger OD to better withstand heat.

                Pay close attention to the contact tip material to avoid premature failure. Consider these options:

                1. Copper contact tips provide good thermal and electrical conductivity for light- to medium-duty applications.

                2. Chrome zirconium contact tips are harder than copper ones and are good for higher-amperage applications. They are also a good option if a company experiences ongoing instances of keyholing — oblong wear on the bore that can lead to an unstable arc and premature contact tip failure.

                3. Contact tips are available in the marketplace that feature proprietary materials and design. These tips cost more than copper or chrome zirconium contact tips but have been shown to last more than 10 times as long. They are designed for pulsed, spray transfer or CV MIG welding.

                Cross-threading the contact tip is another issue that can lead to downtime. When a contact tip isn’t threaded properly during installation, or if the welding operator introduces dirt or debris to the threads, the gas diffuser can be damaged during installation. This will require replacement and increase costs.

                To avoid cross-threading, look for contact tips with coarse threads that install with fewer turns.

                Getting it straight about liners

                The welding liner has a single and relatively simple purpose: to guide the welding wire from the wire feeder through the power cable to the contact tip. However, it is capable of causing significant problems if it isn’t installed properly.

                AccuLock S contact tip, nozzles, diffusers and liner
                There are consumable systems available that provide error-proof liner installation and require no liner measuring.

                Trimming a liner incorrectly is the most common installation error. A liner that is too short lessens the support of the welding wire as it passes through the length of the gun. This can lead to micro-arcing or the formation of small arcs within the contact tip. Micro-arcing causes welding wire deposits to build up in the tip, resulting in an erratic arc and burnbacks. In more extreme cases, micro-arcing can cause MIG gun failure due to increased electrical resistance throughout the front-end consumables and gun neck. It may also prompt the welding operator to increase voltage in an effort to rectify poor welding performance, which can cause the gun to overheat.

                On the other hand, a too-long welding liner can lead to kinking and poor wire feeding.

                When trimming a conventional welding liner, avoid twisting it and use a liner gauge to ensure the proper measurement. There are also consumable systems available that provide error-proof liner installation and require no liner measuring. The gas diffuser locks the liner in place while concentrically aligning it with the power pin and contact tip to eliminate any gaps. The welding operator or maintenance personnel feeds the liner through the neck of the gun, locks it in place and cuts the liner flush with the back of the power pin.

                As with contact tips, remember that quality matters when it comes to welding liners. Always select a stiffer liner, so it is capable of supporting the wire as it feeds from the spool through the power pin and the length of the gun.

                Final considerations

                Paying close attention to MIG gun consumables is important to gaining good welding performance. That means looking at the overall quality of the products being purchased; the manner in which they are inventoried, stored and handled; and how they are being installed. Always follows the consumable manufacturer’s recommendations, and when in doubt, contact their customer service or a trusted welding distributor for help.


                  Optimizing Shielding Gas Performance in MIG Welding

                  Optimizing Shielding Gas Performance in MIG Welding

                  Image of liver welding with a semi-automatic MIG gun

                  Using the wrong shielding gas for MIG welding applications — or having improper gas flow — can significantly impact weld quality, costs and productivity. Shielding gas protects the molten weld pool from outside contamination, so it’s critical to choose the right gas for the job.

                  Learn more about which gases and gas mixes are best suited for certain materials, along with some tips for optimizing gas performance — and saving money — in your welding operation.

                  This article was published in The WELDER. To read the entire story, please click here

                    5 Misconceptions About Robotic Welding Guns and Consumables

                    5 Misconceptions About Robotic Welding Guns and Consumables

                    Tregasskiss Automatic application

                    Robotic MIG welding guns and consumables are an important part of the welding operation yet are frequently overlooked when investing in robotic welding systems. Companies may often choose the least expensive option when, in reality, purchasing quality robotic MIG guns and consumables can lead to significant cost savings in the long run. There are many other common misconceptions about robotic MIG guns and consumables that, if corrected, can help increase productivity and decrease downtime for the entire welding operation.

                    Here are five common misconceptions about MIG guns and consumables that may be affecting your robotic weld cell.  

                    This article has been published as a web-exclusive on thefabricator.com. To read the entire story, please click here


                      MIG Welding Basics: Techniques and Tips for Success

                      MIG Welding Basics: Techniques and Tips for Success

                      It’s important for new welding operators to establish proper MIG techniques in order to achieve good weld quality and maximize productivity. Safety best practices are key, too. It’s just as important, however, for experienced welding operators to remember the fundamentals in order to avoid picking up habits that could negatively impact welding performance.

                      From employing safe ergonomics to using the proper MIG gun angle and welding travel speeds and more, good MIG welding techniques provide good results. Here are some tips.

                      Proper ergonomics

                      Man welding showing proper ergonomics
                      A comfortable welding operator is a safer one. Proper ergonomics should be among the first fundamentals to establish in the MIG process (along with proper personal protective equipment, of course).

                      A comfortable welding operator is a safer one. Proper ergonomics should be among the first fundamentals to establish in the MIG welding process (along with proper personal protective equipment, of course). Ergonomics can be defined, simply, as the “study of how equipment can be arranged so that people can do work or other activities more efficiently and comfortably.”1 The importance of ergonomics for a welding operator can have far reaching effects. A workplace environment or task that causes a welding operator to repetitively reach, move, grip or twist in an unnatural way, and even staying in a static posture for an extended period of time without rest. All can lead to repetitive stress injuries with life-long impacts.

                      Proper ergonomics can protect welding operators from injury while also improving productivity and profitability of a welding operation by reducing employee absences.

                      Some ergonomic solutions that can improve safety and productivity include:

                      1. Using a MIG welding gun with a locking trigger to prevent “trigger finger”. This is caused by applying pressure to a trigger for an extended period of time.

                      2. Using a MIG gun with a rotatable neck to help the welding operator move more easily to reach a joint with less strain on the body.

                      3. Keeping hands at elbow height or slightly below while welding.

                      4. Positioning work between the welding operator’s waist and shoulders to ensure welding is being completed in as close of a neutral posture as possible.

                      5. Reducing the stress of repetitive motions by using MIG guns with rear swivels on the power cable.

                      6. Using different combinations of handle angles, neck angles and neck lengths to keep the welding operator’s wrist in a neutral position.

                      Proper work angle, travel angle and movement

                      The proper welding gun or work angle, travel angle and MIG welding technique depends on the thickness of the base metal and the welding position. Work angle is “the relationship between the axis of the electrode to the welders work piece”. Travel angle refers to employing either a push angle (pointing in the direction of travel) or a drag angle, when the electrode is pointed opposite of travel. (AWS Welding HandBook 9th Edition Vol 2 Page 184)2.

                      Flat position

                      When welding a butt joint (a 180-degree joint), the welding operator should hold the MIG welding gun at a 90-degree work angle (in relation to the work piece). Depending on the thickness of the base material, push the gun at a torch angle between 5 and 15 degrees. If the joint requires multiple passes, a slight side-to-side motion, holding at the toes of the weld, can help fill the joint and minimize the risk of undercutting.

                      For T-joints, hold the gun at a work angle of 45 degrees and for lap joints a work angle around 60 degrees is appropriate (15 degrees up from 45 degrees).

                      Horizontal position

                      In the horizontal welding position, a work angle of 30 to 60 degrees works well, depending on the type and size of the joint. The goal is to prevent the filler metal from sagging or rolling over on the bottom side of the weld joint.

                      Vertical position

                      Image of live welding with a semi-automatic MIG gun
                      From employing safe ergonomics to using the proper MIG gun angle and welding travel speeds and more, good MIG techniques provide good results.

                      For a T-joint, the welding operator should use a work angle of slightly greater than 90 degrees to the joint. Note, when welding in the vertical position, there are two methods: weld in an uphill or a downhill direction.

                      The uphill direction is used for thicker material when greater penetration is needed. A good technique for a T-Joint is call the upside-down V. This technique assures the welding operator maintains consistency and penetration in the root of the weld, which is where the two pieces meet. This area is the most important part of the weld.The other technique is downhill welding. This is popular in the pipe industry for open root welding and when welding thin gauge materials.

                      Overhead position

                      The goal when MIG welding overhead is to keep the molten weld metal in the joint. That requires faster travel speeds and work angles will be dictated by the location of the joint. Maintain a 5 to 15 degree travel angle. Any weaving technique should be kept to a minimum to keep the bead small. To gain the most success, the welding operator should be in comfortable position in relation to both the work angle and the direction of travel.

                      Wire stickout and contact-tip-to-work distance

                      Wire stickout will change depending on the welding process. For short-circuit welding, it is good to maintain a 1/4- to 3/8-inch wire stickout to reduce spatter. Any longer of a stickout will increase electrical resistance, lowering the current and leading to spatter. When using a spray arc transfer, the stickout should be around 3/4 inch.

                      Proper contact-tip-to-work distance (CTWD) is also important to gaining good welding performance. The CTWD used depends on the welding process. For example, when using a spray transfer mode, if the CTWD is too short, it can cause burnbacks. If it’s too long, it could cause weld discontinuities due to lack of proper shielding gas coverage. For spray transfer welding, a 3/4-inch CTWD is appropriate, while 3/8 to 1/2 inch would work for short circuit welding.

                      Welding travel speed

                      The travel speed influences the shape and quality of a weld bead to a significant degree. Welding operators will need to determine the correct welding travel speed by judging the weld pool size in relation to the joint thickness.

                      With a welding travel speed that’s too fast, welding operators will end up with a narrow, convex bead with inadequate tie-in at the toes of the weld. Insufficient penetration, distortion and an inconsistent weld bead are caused by traveling too fast. Traveling too slow can introduce too much heat into the weld, resulting in an excessively wide weld bead. On thinner material, it may also cause burn through.

                      Final thoughts

                      When it comes to improving safety and productivity, it’s up to the experienced veteran welding operator as much as the new welding to establish and follow proper MIG technique right. Doing so helps avoid potential injury and unnecessary downtime for reworking poor quality welds. Keep in mind that it never hurts for welding operators to refresh their knowledge about MIG welding and it’s in their and the company’s best interest to continue following best practices.

                      1. Collins Dictionary, “ergonomics,” collinsdictionary.com/dictionary/english/ergonomics.
                      2. Welding Handbook, 9th ed., Vol. 2, Welding Processes, Part 1. American Welding Society: Miami, Fla., p. 184. 

                        Implementing Robotic Welding: What to Know to Be Successful

                        Implementing Robotic Welding: What to Know to Be Successful

                        The potential advantages of robotic welding are well known — increased productivity, improved quality and greater cost savings compared to semi-automatic welding. But the question is: How do companies best implement this technology to gain these benefits? And how can they ensure a quick return on the investment (ROI)? Simply stated, planning.

                        More preparation upfront helps minimize the cost and time for correcting errors in the robotic welding system once it has gone into production. From the welding power source to the robot or weld process to the gun and consumables, each component should be thoroughly researched to make sure it is feasible to operate in the weld cell — not just on paper, but in reality.

                        Take advantage of turnkey integrators who run their own process and capability studies. They can provide useful double checks to a plan and often conduct reach studies that model the weld tooling and workpiece. These mock up how the robot would weld in the finished system to test the gun reach and the overall efficiency of the process.

                        Robotic application with canvas
                        When implementing a robotic welding system, every component should be thoroughly researched to make sure it is feasible to operate in the weld cell — not just on paper, but in reality.

                        Also remember, success in robotic welding is as much a matter of doing the right thing as it is avoiding pitfalls that could hinder the efficiency of the operation.

                        Budgeting and ROI

                        With planning comes budgeting. A robotic welding cell may be installed on time, produce good weld quality and meet cycle time, but if the implementation and use of the system is over budget it will be an uphill battle to gain a good ROI.

                        Consider the associated goals to help establish a feasible ROI. For example, a company with the goal of producing 1000 parts a day needs to determine how much it can make from those parts. From there, it would subtract the cost of utilities and labor, along with the cost to make the product and the cost of raw materials, to determine a budget on equipment costs that would make the company profitable. If this equipment will only be used for 5 years, the company may need a quicker ROI than if it’s planning to use the robotic welding system for 10 years or more.

                        Companies can make the most of their budget by considering equipment that could be reused. This can cut down on the investment in the long run. Robots can have an extensive life if maintained well, allowing them to be re-purposed from project to project. The same holds true with welding power sources and nozzle cleaning stations.

                        Ultimately, ROI depends on the company and what practices it follows for making profit. Some may be able to allow the equipment to take 18 months or more to pay for itself if the company plans on re-using or re-purposing the welding robots on multiple platforms over the next 10 years. Others may stand by the goal of a one-year ROI, which is common.

                        Effective training

                        Proper training is important for keeping a robotic welding system running successfully and profitably in the long term. Robot integrators and other equipment manufacturers often offer training as part of the implementation process. This training provides welding operators with a knowledge of robotic welding in general, as well as providing the information they need to operate the robot effectively for the application at hand. A well-trained operator will also be able to determine ways to maximize the efficiency of the robotic weld cell. They do this by troubleshooting and resolving issues quickly, keeping the robot online and supporting greater productivity and cost savings.

                        Image of robotic welding with sparks
                        Proper training is important for keeping a robotic welding system running successfully and profitably in the long term. Robot integrators and other equipment manufacturers often offer training as part of the implementation process.

                        Likewise, train welding operators to implement PM for the robotic gas metal arc welding (GMAW) gun to gain longer life, reduce downtime and achieve more arc-on time. Regularly check that the gun connections, consumables and power pin are secure. Look for any signs of power cable wear and replace if necessary.Training geared toward the preventive maintenance (PM) of a robotic welding system and the weld cell is also key. For example, spatter build-up on the robotic welding gun can cause grounding issues and build-up on tooling may lead to dimensional movement of the steel from cycle to cycle. The latter can block the datum placements causing gun reach issues.

                        In a worse-case scenario, spatter builds up on equipment over time, creating solid formations that are difficult to remove and prevent the re-use of the equipment. To avoid these problems, train operators to follow a regular cleaning schedule for the weld cell and the equipment.

                        Avoid common mistakes

                        There are several common mistakes that can negatively affect productivity and quality in a robotic welding system. Knowing how to avoid these can help companies make the most out of the equipment and gain greater success. Consider the following:

                        1. Implementing the wrong equipment in a robotic welding cell can lead to spending more money than is required. Be sure to rate the power source, robotic GMAW gun and consumables for the application. Doing so helps minimize the risk of premature equipment failures that can lead to unplanned downtime and costly equipment replacement. For example, if a company selects an air-cooled system, but actually requires a water-cooled system for the application, it could incur unnecessary costs to repair or upgrade a failed robotic GMAW gun system that cannot handle the heat.

                        2. Underutilizing the robotic welding system can prevent companies from realizing their full productivity potential. Robotic welding systems should be programmed to maximize the arc-on time during the weld process cycle. In some cases, it may be possible to have fewer robots that weld for slightly longer cycles. This helps drop the initial implementation costs.

                        Welding graphic
                        Robotic welding systems should be programmed to maximize the arc-on time during the weld process cycle. In some cases, it may be possible to have fewer robots that weld for slightly longer cycles. This helps drop the initial implementation costs.

                        Take this example. A company has four robots in cell welding at 30 inches per minute with a cycle time of 60 seconds. These robots are inefficient since they are only welding half of the cycle time. That could be due to the positioner rotating for weld access, too slow of robot air cut movements, poor welding angles or other limiting factors. In this scenario, the total length of completed welds for all four robots is 60 inches (30 in. / min. x 1 min. / 60 seconds x 30 seconds of welding per robot = 15 inches of weld per robot).

                        An alternative here is to keep the cycle time at 60 seconds and drop down to three robots by improving items like the weld angles, creating quicker air cuts between welds, utilizing gun reaming during positioner movements and more. Now with improvements, the robots could weld at an average of 35 inches per minute for 35 seconds each cycle. That provides an average of 20 inches of weld per cycle per robot, allowing for the same total of 60 inches of weld with one less robot.

                        3. Underutilizing available labor can also hinder productivity. While companies should take care not to overload operators, it’s important to balance manpower in robotic welding process so that employees are efficient and busy at the same time. If an operator is idle waiting for the weld cycle to complete, there could be room for process improvements by allocating labor to other activities near the weld cell.

                        4. Poor tooling design can impede quality. Thoroughly plan the tooling design and understand how the parts being welded will impact it. Different parts and materials react differently to heat and may draw, flex or bend during the welding process. Factor in how much heat a given weld sequence generates. The tooling will have to be designed with these in mind. If possible, design tooling to permit welding in the flat or horizontal position with appropriate robotic GMAW gun access. This allows for faster and more consistent results. Finally, remember, less expensive tooling may be attractive when looking at upfront costs, but it can be a pitfall later if it doesn’t meet the demands of the job.

                        5. Overlooking activities outside the robotic weld cell can be detrimental. Plan for part inspection and cosmetic rework, as well as the final stages of palletizing the product if that is part of the operation. Some of these processes can be automated or manual labor driven. These are key stages in a robotic welding operation that can quickly become bottlenecks that cause the entire process to slow down. These bottlenecks can also add unplanned manpower or equipment costs, which can become expensive.

                        Final thoughts

                        Remember that no plan for welding automation can be successful without a good schedule for its implementation. Being thorough is more important than being fast. Set realistic goals for completing the installation of the robotic weld cells and don’t rush or over-complicate the process. For first-time investors in robotic welding starting small can also help ensure greater success.

                        Once the robotic weld cell or cells begin operating, keep in mind that the startup may not be perfect. There may be adjustments required to optimize performance to gain the best productivity and quality.

                          Preventive Maintenance for Reamers, Accessories and Other Peripherals

                          Preventive Maintenance for Reamers, Accessories and Other Peripherals

                          From reamers or nozzle cleaning stations to wire cutters and anti-spatter sprayers, welding peripherals and accessories can contribute significantly to the success of a robotic welding operation. In addition to improving weld quality, they can also help companies maintain high levels of productivity.

                          Image of TT3 Reamer
                          A reamer requires the most attention, as this peripheral operates regularly, performing essential welding nozzle cleaning that helps keep the robotic welding cell up and running and quality on par.

                          Reamers, in particular, are most prevalent in automotive manufacturing, where uptime and quality are critical. This peripheral cleans the welding consumables — for example, welding nozzles and gas diffusers — free of spatter, and most automotive welding operations rely on the process after virtually every weld cycle. Other industries, such as heavy equipment manufacturing, also employ reamers and other peripherals in their robotic welding operations, as do some general manufacturers.

                          It’s not by chance that peripherals work the way they do. Like any equipment, caring for them with routine preventive maintenance (PM) is important to gaining optimal performance and longevity.

                          PM tips for reamers and accessories

                          A reamer requires regular attention since it operates frequently during the weld cycles. Its job is important though, as it performs essential welding nozzle cleaning that helps keep the robotic welding cell up and running and quality on par. With the PM for this equipment also comes PM for its associated accessories: the lubricator, cutter blades and anti-spatter sprayer. All require varying levels of PM activities — some daily, weekly, monthly or yearly.

                          In addition to inspecting the consumables for wear and replacing as needed, follow this PM routine on a daily basis:

                          1. Check that the consumables are aligned properly to the reamer. This helps ensure that the jaws of the reamer clamp the nozzle to the V-block correctly and that the consumables are lined up concentric and parallel to the cutter blade for optimal spatter cleaning.
                             
                          2. Clean the spindle cover shroud free of spatter and also clean the clamp jaw and V-block surfaces to gain proper nozzle alignment. Use a brush or compressed air. Look for any signs of wear on these components.
                             
                          3. Make sure the air lines connected to the reamer are free of frays, as leaks will prevent the reamer from receiving enough air to remove spatter properly. Look for any damage to the interface cable.
                             
                          4. Check the oil level in the lubricator reserve — the reamer motor depends on a consistent supply of oil. Also check the level of anti-spatter liquid in the anti-spatter sprayer. Fill as needed. An option to simplify PM of the anti-spatter sprayer is to employ a multi-feed system that allows 5- or 55-gallon drums of anti-spatter liquid to be connected to a manifold system to feed multiple sprayers on multiple reamers. This eliminates the need for daily reservoir fills.
                          Image of a lubricator
                          Check daily that the lubricator is working properly with the right level of oil and clean the filter weekly, replacing it as needed.

                          On a weekly basis, continue to examine the integrity of the consumables and follow these guidelines:

                          1. Inspect the cutter blades for dullness, clogging and possible breakage, replacing as necessary. Note the service life of cutter blades will vary based on the application.
                             
                          2. Again, check that the lubricator is working properly with the right level of oil, and clean or replace the filter as needed.
                             
                          3. Check the LEDs to ensure reamer and controller communication, and wipe the nozzle detect proximity sensors clean so they can function properly.
                             
                          4. Look over the spray head on the anti-spatter sprayer to be sure it is delivering a normal amount of liquid spray. Clean the head and adjust as necessary.

                          Monthly PM for reamers and accessories requires less steps but is more intensive. It may require scheduling a time off cycle to complete.

                          1. Check that the belt tension lock screw and bolt are securely tightened.
                             
                          2. Examine the spindle unit for wear, replacing if necessary, and inspect the solenoids, spooling them to prevent leaks and to make sure they are operating properly.

                          Lastly, on an annual basis:

                          1. Inspect the drive belt for signs of fraying and replace as necessary.
                             
                          2. Replace the spindle cap seal and repair any visible damage.
                             
                          3. Perform a complete cleanup of the reamer and anti-spatter sprayer.

                          While it may seem time-consuming to implement these PM measures, they can typically be completed during routine pauses in production. More intensive activities can be scheduled so as to prevent interruption to production. Ultimately, the PM is time well spent and can help protect the investment in the reamer and its accessories.

                          PM tips for wire cutters

                          Wire cutters are increasingly being used in automotive and other manufacturing operations. This equipment is integrated into a reamer configuration and used in conjunction with a wire brake on the robotic MIG gun. The wire brake prevents the welding wire from moving, while the wire cutter cuts it at a set distance. This allows for a consistent wire stickout so the robot can touch sense and track the joint before welding. The results are more accurate weld placement and smooth arc starting. 

                          TOUGH GUN wire cutter
                          Wire cutters are increasingly being used in automotive and other manufacturing operations and can help with smooth arc starting.

                          PM for wire cutters is relatively simple.

                          1. On a daily basis, check the airlines and interface cable for leaks or frays. Be sure that the solenoid valve is providing air to the system.
                             
                          2. Weekly, check that the cutter blades are sharp enough to cut the wire. Look for signs of dullness, looseness or breaks. Replace as needed. Also empty the wire catcher basket.
                             
                          3. Quarterly, apply general purpose grease (NLGI Grade 1-1) through the grease fittings on the sides of the main body of the wire cutter. This helps lubricate the sliding surfaces of the equipment.

                          The value of peripherals

                          Peripherals like reamers with anti-spatter sprayers and wire cutters can help companies realize a greater return on their investment in a robotic welding system. They aid in high weld quality, minimize rework and help meet productivity goals. Train welding operators to follow recommended PM activities as a part of a routine care of the weld cell. The time and cost to care for them properly will be small in comparison to the improvements they can provide to the bottom line. 


                            MIG Welding Consumables Reduce Wire Feeding Issues and Downtime

                            MIG Welding Consumables Reduce Wire Feeding Issues and Downtime

                            When MIG welding consumables aren’t properly installed or maintained, it can result in wire- feeding issues and weld quality problems. Troubleshooting and correcting these challenges can cost hundreds of dollars — and hours per day — in a manufacturing operation.

                            Welder bent over MIG welding part on table
                            Consumables that simplify the installation process and help eliminate errors reduce downtime for changeover and troubleshooting and decrease costs.

                            As the industry faces a shortage of skilled welders and those entering the profession have less experience, it may be more common for welders to incorrectly install MIG gun consumables and liners.

                            Consumables that simplify the installation process can help eliminate errors, reduce downtime for changeover and troubleshooting, and decrease costs.

                            Learn how new consumables available in the marketplace can help address wire-feeding problems and the role they play in maximizing throughput and productivity.

                            The cost of poor consumable performance

                            Not addressing poor consumable performance can result in, among other problems, lower-quality parts and expensive rework.

                            Wire-feeding issues are some of the most common complaints in the welding industry. Often, improper trimming or installation of the MIG gun liner is the cause of these problems.

                            As with other consumables, the MIG gun liner wears out over time and must be changed periodically. Typically, replacement liners are longer than necessary and must be trimmed appropriately for the style and length of the MIG gun. Trimming the liner to the proper length can be difficult. In some cases, the welder may change the liner without taking the time to complete the proper steps of installation or may not know the proper steps.

                            This can result in a host of problems. A liner that is cut too short can lead to the issues a lot of welders experience: wire chatter, erratic arc and burnback. A too-long liner, which happens less frequently, results in a tight fit and can cause the wire to weave and curve as it feeds through the gun. If the operator continues to weld without diagnosing the cause of any of these problems, it may result in bad welds that require rework or result in scrap.

                            It seems to be common in the industry that welders typically change the contact tip at the first sign of trouble with the welding gun, and this may help for a short-term fix. But if the liner is the root cause, the problem will repeat itself, leading the welder to use more tips than if a correctly trimmed liner was installed. This increases costs due to wasted consumables and downtime for changeover.

                            In some operations, welders don’t install or trim liners. Instead, MIG guns are taken to a maintenance department whenever a liner must be changed. This adds downtime and costs and decreases throughput in the operation.

                            Error-proof liner replacement

                            Image of AccuLock S Consumables family including contact tip, nozzle, diffuser, liner and power pin
                            Improper trimming or installation of the MIG gun liner is often the cause of wire feeding problems. AccuLock S consumables from Bernard takes the guesswork out of liner trimming and installation in semi-automatic welding to simplify the process and reduce downtime.

                            Solutions that are designed to address liner trim length errors and poor wire feeding can reduce troubleshooting, downtime and rework — ultimately saving money. 

                            The AccuLock™ S consumables system from Bernard® take the guesswork out of liner trimming and installation in semi-automatic welding operations. The system offers an error-proof liner replacement process that eliminates measuring and incorrectly trimming liners.

                            In contrast to most MIG gun liners that load from the back of the gun, AccuLock S liners load through the neck at the front of the gun. The liner is then locked and trimmed flush with the power pin at the back of the gun, which eliminates the need to measure.

                            This design also eliminates doubt about proper liner length — and the time spent troubleshooting liner trimming issues — because operators can simply look at the back end of the gun to see that the liner is correctly trimmed and in place.

                            With traditional MIG guns, welders can’t see if a liner is cut too short, since the end of the liner that’s been trimmed is hidden under the nozzle and gas diffuser. A welder would have to remove all the consumables to see the liner inside the gun.

                            Optimize wire feeding

                            In addition, the system optimizes wire feeding because the liner is locked and concentrically aligned to both the contact tip and the power pin without the use of fasteners. Capturing the liner at both ends of the gun keeps the liner from extending and contracting based on gun position — and it allows for a flawless wire-feeding path.

                            Typically, the longer the welding gun, the more the cable bends and twists. Even when a traditional liner is perfectly cut and installed, the liner gets pushed forward and back inside the gun as it’s used, since the liner is affixed at the back end of the gun but free floating at the front end of the gun. This liner movement can result in wire chatter and erratic arc.

                            When the liner is affixed at both ends of the gun, as with the AccuLock S consumables system, welders are assured the liner won’t pull back, or push into the contact tip — allowing for smooth, uninterrupted delivery of the wire to the weld pool.

                            And because the liner is concentrically aligned with the contact tip, it creates less mechanical wear on the tip’s interior diameter, possibly leading to longer life by reducing the risk of keyholing associated with misaligned liners and contact tips. Reducing keyholing also lessens the opportunity for an erratic arc, excessive spatter and burnback, all issues that shorten contact tip life.

                            Cutaway graphic of AccuLock S Power Pin Assembly showing liner trimmed flush
                            AccuLock S consumables are designed to eliminate liner trimming errors and optimize wire feeding to help operations reduce downtime, costs and rework — maximizing throughput and efficiency. 

                            Maximize performance and life 

                            Additional features of the new consumables system also contribute to optimized MIG gun performance:

                            Cool, connected contact tip: Sixty percent of the AccuLock contact tip is buried in the gas diffuser to protect it from heat damage. As the shielding gas flows through the gun, it cools the contact tip tail inside the gas diffuser, which helps reduce heat and wear. These features differ from traditional tips that screw onto the gas diffuser with little to no portion of the contact tip exposed directly to the shielding gas as it exits the diffuser to the arc. A tapered design of the consumables tightly locks the conductive parts together to minimize electrical resistance and further reduce heat buildup.

                            Versatile nozzle: A patent-pending nozzle design allows operators to choose thread-on or slip-on — with the same nozzle part number. Typically, nozzles are either thread-on or slip-on style, a choice that often comes down to welder preference. A thread-on nozzle is locked in, while a slip-on nozzle can be adjusted to different heights and easily pulled off.

                            With AccuLock S consumables, the same nozzle can be used as a slip-on or thread-on nozzle, and the change is determined by using a different diffuser. This allows operations to greatly simplify their consumables inventory and changeover, with fewer parts to manage. In addition, a steel retaining ring and friction lock on the diffuser help prevent the nozzle from unthreading or loosening when it’s threaded on. This also helps eliminate the potential for gas leaks at the back of the nozzle or insufficient gas coverage of the weld — a common occurrence when traditional thread-on nozzles loosen over time.

                            Coarse threads: The AccuLock contact tip features coarse threads, making it less likely to become cross-threaded and also requires fewer turns to install or remove — speeding up tip replacement. One full turn disengages the contact tip from the diffuser.

                            Reduce wire-feeding and weld quality issues

                            Significant time and money can be spent troubleshooting weld quality problems and wire- feeding issues, such as erratic arc, bird-nesting and burnback. In addition, many welding operations are dealing with increasing welder retirements and turnover, which can increase troubleshooting time associated with less experienced welders installing consumables.

                            The AccuLock S consumables system is designed to eliminate liner trimming errors and optimize wire feeding to help operations reduce downtime, costs and rework — maximizing throughput and efficiency.

                              Robotic Welding: Troubleshooting FAQs

                              Robotic Welding: Troubleshooting FAQs

                              Every operation wants to avoid downtime, as well as the cost for troubleshooting problems in the robotic welding cell. But sometimes issues happen, whether it’s due to equipment failure or human error.

                              Since most companies invest in welding automation to boost throughput and profitability, getting a robotic welding cell back online as quickly as possible is critical to production and the bottom line. The first things to consider are whether anything has changed in the welding process or with the equipment, or if the operator has recently reprogrammed the robot. In many cases, evaluating the most recently changed variable can help you pinpoint an issue’s cause.

                              Image of welding operator checking fixturing in robotic MIG welding cell
                              Since most companies invest in welding automation to boost throughput and profitability, getting a weld cell back online as quickly as possible is critical to production and the bottom line.

                              After that, analyzing some of the most frequent sources of trouble in the robotic weld cell can help you get to the root of the problem sooner. Consider these five common issues and ways to fix them.

                              Q: What are causes of poor consumable performance?

                              A: The material being welded and the parameters being used affect welding consumables’ longevity. But if it seems that nozzles, contact tips, diffusers or liners aren’t lasting their typical life or are performing poorly, there could be several causes.

                              Check all connections between welding consumables and tighten them as needed. A loose connection increases electrical resistance and generates additional heat, which can shorten consumable life and cause poor performance. It’s especially important to ensure consumables are properly tightened when the application involves long welds or welds on thick materials, since any rework due to quality issues will cost more time and money in these cases.

                              Common contact tips issues, such as burnback, are often caused by a too-short liner. Always follow the manufacturer’s instructions for liner trimming and installation, and use a liner gauge to confirm length when possible. Over time, debris and spatter buildup inside the liner can contribute to shortened contact tip life. It’s important to create a schedule for changing liners, just as you would for other consumables.

                              If you’re frequently experiencing weld defects like porosity or lack of penetration, this can also stem from a consumables issue. Make sure the contact tip and nozzle are free of debris and replace them as needed.

                              Q: What causes poor wire feeding?

                              A: Erratic or poor wire feeding in robotic welding is a common issue that can ultimately result in poor weld quality. Poor wire feeding can have many causes.

                              Cutting a liner too short is particularly problematic when robotic welding with smaller diameter wires, which have less column strength.

                              Extreme articulation of the robotic MIG gun can also lead to poor wire feeding. Program the robotic MIG gun cable to stay as straight as possible. The robot may not weld quite as fast, but proper gun orientation helps minimize downtime for feeding problems.

                              Image of TOUGH GUN TT3e Reamer with a TOUGH GUN CA3 MIG gun approaching it
                              The taught position of the robotic MIG gun nozzle in relation to the reamer should be concentric to the cutting blade on the reamer to ensure proper cleaning of the nozzle. 

                              Excessive conduit length and multiple bends or junctions can cause poor wire feeding as well. With the drive rolls open, you should be able to pull the wire through the contact tip by hand with minimal effort. If you need to pull with two hands or put your bodyweight into the process, that indicates interference with the wire path between the wire drum and the contact tip. Check for bends tighter than 90 degrees, multiple junctions between sections of conduit or worn conduit sections that can increase drag on the wire. Ideally, the conduit between the drum and the wire feeder should be less than 20 feet, with no junctions or tight bends.

                              Improper drive roll selection and tension setting can also lead to poor wire feeding. Consider the size and type of wire being used and match that to the drive rolls. Inspect drive rolls for signs of wear and replace them as necessary.

                              Q: Why is the cable prematurely failing?

                              A: Whether you have a through-arm robotic welding system, where the cable is routed through the robotic arm, or a standard over-the-arm robotic welding system, premature power cable failure can happen. A power cable that becomes kinked or worn can fail and short-out against the robot casting, leading to costly repairs.

                              To help prevent premature cable wear, consider the programmed path of the robot as well as the power cable’s length. If the robot’s movements cause the cable to bunch up or kink, it can cause the power cable to fail. If the power cable rubs against tooling or catches on components during the programmed cycle, this can also cause premature failure.
                              Proper cable length is also important. A cable that is too short or too long can be stretched beyond capacity or be prone to kinking.

                              Q: Why is there a problem with tool center point (TCP)?

                              A: In robotic welding, TCP refers to the location of the end of the welding wire with respect to the end of the robot arm. If you are experiencing inconsistent welds or welds that are off-location, this may stem from a problem with TCP.

                              If the robotic MIG gun neck is bent or damaged during a collision in the weld cell, this can result in TCP issues. Use a neck-checking fixture or neck alignment tool to help ensure proper angle of the neck bend. Also, be sure the neck and consumables are installed and torqued properly. Failure to do so may affect TCP. 

                              However, a problem with off-location welds isn’t always caused by TCP issues. Improper fixturing or part variations may also be the root cause. If a TCP check using the robotic program turns up with no issues, a part or position variation is the likely culprit.

                              Q: How do I fix poorly performing peripherals?

                              A: Companies often implement peripherals, such as reamers or nozzle cleaning stations, to optimize robotic welding performance and get more life out of consumables. But a problem with the reamer can cause spatter buildup on the consumables.

                              TOUGH GUN Neck Checking Fixture image
                              A collision in the weld cell that bends or damages the neck of the robotic MIG gun can result in tool center point issues. A neck-checking fixture or neck alignment tool can help ensure a proper angle of the neck bend.

                              Reamers can perform poorly for three common reasons:

                              1. Improperly taught position of the robotic MIG gun nozzle in relation to the reamer. This position should be concentric to the cutting blade on the reamer at the proper insertion depth to ensure thorough cleaning of the nozzle.
                              2. Too much or too little anti-spatter spray in the wrong location. Anti-spatter spray should cover the inside of the nozzle and the outside should be covered within 3/4 of an inch from the bottom of the nozzle. Spray for only a half-second. In production, the anti-spatter should evaporate on contact with a hot nozzle — if your nozzle is dripping, you’re spraying too long.
                              3. Using the wrong cutting blade or improper insertion depth will not allow for proper removal of accumulated welding spatter.

                              Correcting common problems

                              Problems in the robotic welding cell can be as simple as a loose contact tip or more complex like incorrect TCP. Understanding the steps for proper troubleshooting helps narrow down potential causes and can prevent replacement of components that don’t need replacing — so the operation can save money and quickly get back to producing quality parts.

                              Learn more from the Tregaskiss Troubleshooting Guide.

                                Taylor Forklift Operation Reduces Downtime, Costs with Bernard

                                Taylor Forklift Operation Reduces Downtime, Costs with Bernard

                                Taylor Machine Works Inc. has spent over 90 years building a reputation by engineering and producing exactly what its customers need. The company manufactures more than 85 models of powered industrial trucks, including forklifts and material handling equipment for a range of industries.

                                Taylor’s “Big Red” forklifts, featuring the company’s distinctive “Big Red” logo, can handle material weighing up to 125,000 pounds.

                                “We manufactured roughly 750 pieces of rolling stock last year and 40 percent to 50 percent of that is highly customized,” said Matt Hillyer, director of engineering for Taylor, based in Louisville, Mississippi. “Our job is to build products that answer the customer’s needs.”

                                Taylor’s “Big Red” forklifts, featuring the company’s distinctive “Big Red” logo, can handle material weighing up to 125,000 pounds — everything from palleted goods and empty shipping containers in waterfront shipyards to equipment encountering brutal hot and cold environments. Many of Taylor’s customers are small operations with from one to three pieces of equipment. Just one piece going out of service reduces production capacity by a large percentage.

                                “Having high durability, high return on investment and low cost of ownership, those are all very imperative to our customers to make them successful,” said Hillyer. “It’s important for us not only to make custom products that are advanced in technology or state-of-the-art, but we also have to make products that are very simple, easy to work on and have lots of uptime. That’s what our customers are looking for.”

                                Taylor employs some of the best welders in the business to meet those customer demands, but even great welders can’t overcome their tools’ limitations. When Taylor decided to try Bernard® semi-automatic MIG guns and Centerfire™ consumables, they discovered their talented team could take productivity up a few notches —and still gain the best quality.

                                Application photo of a welder in the process of welding
                                All the advantages found by using Bernard Semi-Automatic MIG Guns and Centerfire Consumables align perfectly with Taylor’s commitment to quality and meeting the customer needs.

                                Making the change
                                According to Taylor, sometimes it takes trying a new technology to realize what you’ve been missing. That was the case with the Bernard products — the manufacturers of the Big Red material handling machines had a business epiphany.

                                “Before we changed to Bernard welding products, we didn’t really know we were having a problem,” said Steve Nazary, quality assurance supervisor at Taylor. “When we started using Bernard [MIG guns and consumables], we found that they were much easier and more economical to use for our process.”

                                Bernard semi-automatic MIG guns at 400, 500 and 600 amperages delivered more business benefits.

                                Savings on service repair. “We can replace the liners, the tips, the nozzles” Nazary explained. “You can replace everything on a Bernard gun instead of throwing it away and buying a new one.” The previous guns Taylor used could not be repaired and components weren’t replaceable, resulting in increased costs for new purchases for their large manufacturing operation.

                                Productivity-boosting ergonomics. “The Bernard MIG guns have a better handle on them,” Nazary said. “It fits your hand better. It has an easier trigger to pull. It doesn’t get as hot as the guns we were using before. We were using some handles before that got so hot, you couldn’t hold them anymore.”

                                “Those twisty necks, as I call them, we can loosen them and change the angle to get in harder places. And you can reset them back straight, turn them on any angle. The employees love them.”

                                Craig Callahan, Quality Control Welding Inspector

                                Easier-to-use rotatable necks. Guns with multiple neck position options that are all easy to adjust let Taylor welders operate comfortably and precisely in more situations. Rather than turning the entire gun to get the right position to reach a weld joint, welders simply adjust just the neck of the gun to a better angle.

                                Rather than turning the entire gun to get the right position to reach a weld joint, welders simply adjust just the neck of Bernard Gun to a better angle.
                                Rather than turning the entire gun to get the right position to reach a weld joint, welders simply adjust just the neck of Bernard Gun to a better angle. 

                                Nazary added that it’s also easy to change necks on the Bernard MIG Guns to reach into tighter spaces. “We have multiple necks and they only take two or three seconds to swap them out,” he said.

                                Centerfire™ consumables also proved to last much longer than products Taylor had used previously, reducing the need to change contact tips from multiple times per day to just once a day, on average. These consumables feature a non-threaded contact tip that is tapered at the base to seat easily in the gas diffuser. The result is better heat dissipation and a longer life. Plus, they are quick to change over. 

                                Welder leaning over project in a weld cell
                                When Taylor decided to try Bernard™ Semi-Automatic MIG Guns and Centerfire™ Consumables, they discovered their talented team could take productivity up a few notches —and still gain the best quality. 

                                “We can change the Centerfire consumables with ease. We don’t have to have tools. You just twist the nozzle off, pull it off and pop another contact tip in and twist the nozzle back on,” said Nazary.

                                Centerfire consumables also provide better gas flow for better welds and less rework.

                                “With the other consumables that we were using, you would get different gas flows,” said Nazary. “With the Bernard products, we have consistent flow all the time.”

                                Helping Taylor Machine Works serve customers
                                All the advantages found by using Bernard semi-automatic MIG guns and Centerfire consumables align perfectly with Taylor’s commitment to quality and meeting the customer needs. And the reliability of the products fits well with the company’s slogan: “Depend on Red.”

                                “It’s absolutely imperative to make our products successful for the customer,” said Hillyer. “We also look to our suppliers, like Bernard to provide us with the best technology. They help us incorporate the right technology to make sure that we do have the most durable truck on the market.”