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Implementing a Robotic Welding System: 5 Common Questions Answered

Implementing a Robotic Welding System: 5 Common Questions Answered

Estimated reading time: 7 minutes

Many manufacturing operations want to improve productivity and weld quality. Robotic welding can often help achieve these goals. But success with a welding robot doesn’t happen by chance. It takes a lot of upfront planning to help minimize the time and money you need later to make improvements or fix issues. 

Before getting started, consider how these common questions could impact the way you establish a repeatable and consistent robotic welding operation — and how you can get the most out of it. 

How do I choose the right welding wire?

A: The filler metal used in a robotic welding system plays a critical role, as it can affect productivity, weld quality and overall costs. When you choose a wire for robotic welding applications, consider two things: the type and the thickness of the material being welded. 

Across various industries, solid wire has been the standard for robotic welding. However, metal-cored wire may offer better productivity and higher quality benefits, especially for manufacturers of heavy equipment, automotive exhaust, chassis and wheels. Metal-cored wire not only allows for faster travel speeds and higher deposition rates, but it also more effectively controls spatter levels to reduce post-weld cleanup. Last, it offers improved welding through mill scale, which helps eliminate pre-weld grinding. 

When in doubt, you can get suggestions from experienced welding equipment and filler metal manufacturers to help you match a welding wire to your process needs. 

What type of welding gun and consumables do I need? 

A: Performance in a robotic weld cell is significantly affected by your choice of robotic welding gun and consumables, including the nozzle, contact tip and liner. The right combination of gun and consumables can reduce unplanned downtime, increase lifespan and improve overall equipment effectiveness (OEE) in your weld cell. 

There are three types of robotic guns to choose from, depending on your duty cycle and amperage ratings: air-cooled, water-cooled and hybrid. It’s possible for air-cooled guns to reach ratings of 350 to 385 amps at 100% duty cycle with mixed gases. Guns with this rating are well-suited for a variety of applications and help eliminate the need for water-cooled guns, which can be more complex and expensive to maintain. However, hybrid air/water-cooled designs incorporate water cooling on the front of the neck with an air-cooled cable. This design is good for applications with borderline air-cooled duty cycles that experience a higher frequency of consumable changeover. The hybrid gun is the best option to provide an additional rating boost while effectively cooling the consumables, leading to longer lifespans.
 
Robotic welding systems typically operate at higher duty cycles (compared to semi-automatic welding) and may use transfer modes that can be harsh on consumables. Consider using heavy-duty copper or chrome zirconium contact tips or high-quality tips designed specifically for pulsed welding. Chrome zirconium contact tips resist physical wear (or the keyholing effect) better than copper tips and are ideal for applications with long welds. Make sure to undersize the contact tip from the wire size when using 500-pound-plus wire drums to help ensure consistent wire contact with the tip due to the wire cast. Keep the tips on par with the wire size in small wire packaging. 
Nozzle material also plays a factor in the application. Brass nozzles are stronger and have a lower spatter adhesion compared with copper, but brass is more brittle at higher temperatures. In short, brass handles spatter best while copper best handles higher heat.

Choosing a quality liner pays dividends in reducing your unplanned downtime. The majority of time, burnback in contact tips is a direct result of poor wire feeding or a liner cut too short. An accurately trimmed, quality liner will help to consistently improve wire feeding by reducing drag. The result is longer-lasting contact tips and improved robot uptime.

Chart with information on selecting air-cooled, water-cooled, hybrid robotic MIG guns

How do I select proper weld settings? 

A: Several factors, such as material type, wire size and material thickness, influence the proper weld settings for an application. Some welding power sources have the ability to suggest recommended parameters based on the operator’s input for the application. 

When a machine doesn’t have this technology, finding the correct parameters can involve some trial and error on your part to dial in heat and penetration. Consult with the robot manufacturer, welding power source manufacturer or system integrator. These partners can offer expertise and assist in choosing and testing specific materials to establish the proper weld parameters.

Why is tool center point (TCP) so important?  

A: Establishing an accurate tool center point provides consistency and repeatability across parts and is vital for your system to maintain quality welds.

You can set your own standards for the acceptable amount of TCP drift based on the application and type of welds being made. To set the tolerance of TCP variation, an acceptable starting point can be half of the thickness of the wire diameter. Also keep in mind that your TCP correlates with your contact tip wear — the more key-holed a tip, the more off location your TCP will be.
Touch-sensing features that monitor TCP and track any shifts from the original setting are available on many robotic systems today. If a gun is out of acceptable TCP range, you can remove the neck and recalibrate it to the original specifications with a neck-straightening fixture. TCP can also be automatically adjusted internally by the robot on some systems. 

It’s a good idea to schedule regular TCP checks. For example, it can be done every weld cycle, at the end of every shift or when the gun goes through a reamer cycle. The frequency of TCP checks is a matter of your priority preference. While it can be time-consuming to check after every shift, in the long run it can save money by avoiding rework if problems are caught early.

Closeup of weld cell supervisor programming robot with teach pendant

How do I program the robot path? 

A: Much like programming the weld settings, programming the robot path may also involve some trial and error. When you initially program the robot’s path, think about four factors: the application, the material type, the welding process you are using and the gap size being filled. The travel angle — and whether it’s a push or pull weld — will impact the weld quality and aesthetic. Dialing in the correct path to achieve your desired results can take time. 

Having the robot move to perch points or ready-to-enter points once the home positions are set helps to keep the robot safely away from potential collision areas. It also allows the system to move with air-cut moves to and from these points quickly and effectively. 

When you program the robot to move to a weld, it’s common to set the approach point just above the weld start location. The robot should approach the start location at a slower and safer speed before it strikes an arc. This approach position provides a good lead-in and typically does not require adjustment unless the weld is relocated. Some robotic systems have technology that assists in setting the initial robot path.  

The robot’s welding location can play a role in premature gun failures. Heavy articulation in the gun or an excess of +/-90 degrees, especially during welding, can cause accelerated cable failures. Minimizing your robot’s axis five and six during welding can help extend gun life by reducing wear.

Tips for robotic weld cells 

Many variables, including proper cable and consumables selection and TCP control, play an important role in weld quality and gaining successful results with a robotic welding system. Establishing a thorough plan before implementation and continuing to monitor key issues can help you optimize your OEE so you can get the most out of your investment. 


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.


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.

Animation | Tregaskiss TOUGH GUN Reamer Robotic Nozzle Cleaning Stations

Tregaskiss® TOUGH GUN® Reamer Robotic Nozzle Cleaning Stations Animation

Automating spatter removal helps to extend the life of your robotic MIG welding guns and consumables. It can benefit your bottom line, production up-time and throughput. Choose between our TOUGH GUN TT3 reamer (analog model) or our new TOUGH GUN TT3E reamer (Ethernet model) for further enhanced with digital Ethernet communication for better integration.

    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


      Reduce Downtime and Costs with Water-Cooled Robotic MIG Guns

      Reduce Downtime and Costs with Water-Cooled Robotic MIG Guns

      For many fabricators, the choice between an air-cooled and water-cooled robotic MIG welding gun is easy. Their heavy-duty applications simply demand a water-cooled model due to the high amperage and duty cycle requirements of the job — an air-cooled gun would overheat and fail prematurely under such conditions.

      Robotic arm performing a weld
      The weld joint design and type or thickness of the material can help determine whether to convert to a water-cooled MIG gun. 

      In the right application, a water-cooled robotic MIG gun can often prove beneficial by minimizing downtime, increasing productivity and reducing consumable costs. These guns typically have higher duty cycles than air-cooled models and operate at higher amperages, which means they can run for longer periods of time.

      Still, deciding whether an operation would benefit from converting to a water-cooled MIG gun involves a careful analysis of several factors. In addition to considering the amperage requirements and duty cycle, a fabricator should consider the upfront costs, potential return on investment (ROI) and the specific application.

      For example, some fabricators may choose a water-cooled robotic MIG gun because of the length of their welds — they need a long arc-on time to produce long welds, which generates more heat in the gun. Similarly, critical start-and-stop points along a longer weld joint typically require a gun that can handle extended weld times.

      The weld joint design and type or thickness of the material can also help determine whether to switch to a water-cooled MIG gun. For instance, heavy plate sections that have been preheated can generate substantial radiant heat that impacts how well a gun cools, and can adversely affect the life of the front-end consumables. In this scenario, a water-cooled gun would be better suited for the job.

      When deciding whether a water-cooled robotic MIG gun is the best choice for an application, it’s important to keep in mind some maintenance and replacement costs. While a water-cooled gun costs more upfront, there is the possibility to conduct maintenance on each individual component within the cable assembly (e.g. water lines, gas hose, etc). However, an air-cooled cable combines all its components into one common part and if any single component fails, the entire cable needs to be replaced, resulting in higher replacement costs. It is necessary to weigh those factors against each other.

      Understanding water-cooled robotic MIG guns

      Welding guns — whether air or water-cooled — must stay cool to protect the power cable, gun body, neck and consumables from heat damage during welding. That heat takes three forms: radiant heat from the arc; resistive heat from the electrical components in the welding circuit; and reflective heat from the welded part, particularly aluminum or preheated parts.

      Whereas an air-cooled MIG gun relies on the ambient air, shielding gas and arc-off time to dissipate heat, a traditional water-cooled robotic MIG gun circulates a coolant from a radiator unit through cooling hoses inside the power cable and into the gun body and neck. The coolant then returns to the radiator, where the radiator’s baffling system releases the heat absorbed by the coolant. There are also guns available on the market today that cool only the front of the gun, where heat is generated, and still use an air-cooled cable.

      Air-cooled MIG guns also use much thicker copper cables and inner neck tubes, whereas water-cooled robotic MIG guns use much less copper in the power cables and thinner wall sections in the necks because the coolant carries away the resistive heat before it builds. Water-cooled MIG guns, however, do have multiple inner lines that run through the neck to the front-end consumables, making this portion of the gun heavier than an air-cooled neck.

      When to switch to a water-cooled robotic MIG gun

      There are three key indicators that signify a welding operation could benefit from converting to a water-cooled MIG gun:

      1. Excessive consumable usage
      2. Excessive gun temperature (overheating)
      3. Excessive cycle time (high duty cycle)

      All these factors are interconnected, because if the weld is too hot, excessive consumable usage and gun temperature will automatically result.

      In general, water-cooled robotic MIG guns are most beneficial for high-amperage applications and are typically available in 350 to 600 amp models.

      Closely related to amperage is duty cycle, which refers to the amount of time during a 10-minute cycle that the gun can operate at its rated capacity without overheating. Water-cooled robotic MIG guns have varying duty cycle capacities depending on the manufacturer and model. It is important to make the appropriate comparison during the selection process, as some guns may be rated at either 60% or 100% duty cycle, which results in different amperage ratings. 

      Converting to a water-cooled robotic MIG gun

      600 amp robotic water-cooled gun photo
      In general, water-cooled robotic MIG guns are most beneficial for high-amperage applications in the 350- to 600-amp range. 

      Fabricators who plan to change from an air-cooled to a water-cooled robotic MIG gun should follow these three steps to help ensure a smooth conversion.

      Match the existing tool center point (TCP) and approach angle. Be sure to have access to all the weld joints with the new water-cooled MIG gun. Make sure that the tooling will work with the new system. The gun may require a special neck or special mounting arm to achieve the desired TCP. Often, converting to a water-cooled gun will require a new mounting arm and insulating disk to maintain or achieve a specific TCP while changing the dimensions of the neck itself to create better access.

      Ensure overall clearance. A 3-D simulator can help determine whether all parts of the new system will clear all tooling or any other obstructions. In addition to having front-end clearance and access – once installed, it’s important that the gun body and cable bundle fits properly to avoid getting caught on tooling or other equipment. 

      Get a water cooler. It is necessary to invest in a radiator for the new water-cooled robotic MIG gun. Ensure that the water-cooler has been installed and maintained, as per the manufacturer’s specifications.

      Maintenance and usage tips

      Because all the lines and hoses in a water-cooled robotic MIG gun are separate, it is possible to conduct maintenance on individual components if they become damaged. However, due to the lines being internal to the gun, it is difficult to perform preventive maintenance on them. There are options though to care for a water-cooled gun.

      As with an air-cooled MIG gun, it’s important to inspect a water-cooled robotic MIG gun to ensure that all consumables and connections are tight and working properly. Inspect the water lines frequently to make sure they are tight and have no leaks, and replace the O-rings when necessary (e.g. when cracks or wear appears). Ensure there is a flow switch installed in the return line from the gun and the radiator to indicate any leaks within the system — this component will save time and money in the event of a failure.

      Using a reamer or nozzle cleaning station adds significant benefits to the preventive maintenance of water-cooled robotic MIG guns. A reamer eliminates the need to manually clean out the front-end consumables and can, with the addition of an automated sprayer, add anti-spatter compound to help further extend consumable life. This feature adds to the overall cost of the equipment, but it helps increase uptime for production since there is less manual intervention. The ROI is typically worth it.

      It is important to always use the correct coolant — do not fall prey to the notion that it is cheaper to use tap water in a water-cooled gun. Doing so can cause algae growth or mineral build-up and, eventually, lead to costly clogging. Instead, use deionized water or the specially treated coolant solution recommended by the manufacturer. These coolants contain special additives to lubricate internal pumps and O-rings, as well as to prevent algae growth. 

      Lower operating costs

      Although converting to a water-cooled robotic MIG gun is often more of a necessity than a choice (because the application demands it), this type of gun has its value. Applying a water-cooled gun to the appropriate application can result in a more efficient system performance and lower overall operating costs.

      Consider the various costs, specific application needs and joint accessibility to determine whether a water-cooled robotic MIG gun is the best option for the specific robotic application — and don’t hesitate to consult a trusted welding distributor, welding equipment manufacturer or robotic welding system integrator with questions. 


        Maintaining TCP: How Does Your Robotic MIG Gun Neck Factor In?

        Maintaining TCP: How Does Your Robotic MIG Gun Neck Factor In?

        Image of TOUGH GUN TA3 Robotic MIG gun
        The durability of the gun neck — and especially its ability to withstand impacts — is important for maintaining tool center point (TCP).  

        A robotic MIG welding system contains many components that impact the quality of the parts it welds, its productivity and the overall operational costs. Among those, the robotic MIG gun neck plays a larger role than may first be apparent. Why? The durability of the gun neck — and especially its ability to withstand impacts — is important for maintaining tool center point (TCP).

        The value of TCP

        An accurate TCP provides consistency and repeatability from part to part, and is key to the system’s ability to maintain weld positions, especially in assembly line welding where new parts are continually entering the weld cell.

        A productive and efficient robotic welding system places welds in the same place every time. To achieve this, the MIG gun neck needs to stay in its expected position. A weak neck that easily bends during routine welding can lead to TCP problems over time, as can rough handling of the neck during consumable changeover.

        Issues with TCP can lead to additional spatter or missed welds, causing rework or scrapped parts. These cost time and money in lost productivity and in wasted parts. An inaccurate TCP can also cause the neck to crash into parts or tooling, potentially leading to damage and unplanned downtime.

        When selecting a robotic MIG gun neck, look for durable, high quality materials and robust construction. The goal is to have a neck that is strong enough to withstand minor crashes without bending.

        In addition, be certain there is a solid connection from the neck to the gun, and from the gun to the mounting arm in a conventional system or to the robot itself in a through-arm system. Any play in the system can negatively impact TCP.

        Air-cooled or water-cooled gun?

        Image of a neck checking fixture
        A neck inspection fixture, which verifies that the gun’s neck is set to the intended TCP, also allows the neck to be readjusted after a collision or if it becomes bent during routine welding.

        Neck durability varies, depending on if the application uses an air-cooled or a water-cooled robotic MIG gun.

        Some applications require water-cooled guns to protect the gun and the neck in high-temperature continuous welding; however, these guns tend to be less durable in a crash than air-cooled gun necks due to the internal soldering of copper and brass lines for the water passages.

        Air-cooled guns typically feature copper tubes covered with insulation and aluminum, making them stronger and more able to resist an impact.

        Some manufacturers offer a hybrid air/water-cooled robotic MIG gun, in which the water lines run external to the neck. This type of gun tends to have a stronger neck, like an air-cooled gun, which makes it more tolerant to crashes. However, it is important to ensure the water lines do not hit tooling or parts, which can negatively affect TCP or create leaks.

        Getting the best performance

        Some key best practices can help protect the neck and provide consistent TCP:

        Collision Detection

        All robotic welding systems require a form of collision detection to prevent damage to both the robotic MIG gun and the robot arm in the event of an impact. Some robotic systems incorporate robot collision detection software. Systems that do not have built-in collision detection should always be paired with a clutch — an electronic component that attaches to the gun to protect it and the robot from heavy damage in the event of a collision.

        Neck Inspection Fixture

        Image of TOUGH GUN TT3e Reamer with a TOUGH GUN CA3 MIG gun approaching it
        A high-quality reamer securely holds the gun in place during the ream cycle, which reduces the risk of bending the neck and compromising TCP. 

        Another key peripheral is a neck inspection fixture, which verifies that the gun’s neck is set to the intended TCP and allows the neck to be readjusted after a collision or if it becomes bent during routine welding. If neck adjustment is needed, the welding operator simply adjusts the neck to meet the proper specifications. This prevents costly rework due to missed weld joints and can reduce downtime to reprogram the robot to meet the welding specifications with a bent neck.

        Spare Necks

        Having spare necks ready helps gets the system back online quickly. The welding operator need only remove the bent neck in the event of a crash and exchange it with a spare one. The damaged neck can be set aside for inspection later, minimizing interruption to the weld cycle.

        Reamer Quality

        Choose a high-quality reamer to avoid potential damage to the gun or neck. A reamer, or nozzle cleaning station, removes spatter from the nozzle and clears away the debris that accumulates in the diffuser during welding. A high-quality reamer securely holds the gun in place during the ream cycle, which reduces the risk of bending the neck and compromising TCP.

        5. Proper neck and consumable installation and ongoing maintenance are important. Make sure to tighten these components to factory specifications. When changing consumables, remove them with the right tools to avoid bending the gun neck.

        Optimize the system to ensure proper TCP

        In many cases, a robotic welding system can provide a competitive edge — offering greater productivity, quality and cost savings. Take care to protect the MIG gun neck, and follow best practices for setup and maintenance, to help ensure the system maintains optimal TCP and the operation experiences minimal downtime.  


          What to Know About Liners for Robotic Welding Guns

          What to Know About Liners for Robotic Welding Guns

          Image of three QUICK LOAD Liners with Liner Retainers

          The liners used in a robotic gas metal arc welding (GMAW) gun play a significant role in the productivity, cost and quality in your automated welding operation, alongside other consumables such as the nozzle, retaining head (or gas diffuser) and contact tip. Liners run the length of the robotic welding gun and power cable — from the contact tip to the power pin — and act as the conduit through which the wire is fed.

          A poorly installed liner can lead to problems with bird-nesting and excessive debris in the liner, which can both cause wire feeding issues that lead to downtime — the enemy of any robotic welding operation.

          For this reason, it is imperative to select the right liner for the wire type and diameter being used and to trim it to the proper length.

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

            Choose the Right Power Cable to Reduce Downtime in Robotic Welding Applications

            Choose the Right Power Cable to Reduce Downtime in Robotic Welding Applications

            In robotic MIG welding applications, minimizing downtime is key. It reduces costs and improves efficiencies to help an operation meet its production goals. Gaining the best performance, in part, depends on the equipment being used. Having the right robotic MIG gun and power cable, for example, is critical. 

            There are several factors to consider when determining the right gun style and cable length for the application. Prioritizing these are important, as using the wrong length cable can cause problems ranging from premature cable failure to poor wire feeding.  

            Conventional vs. through-arm guns 

            Before selecting the power cable length, first consider whether a conventional gun or a through-arm robotic gun is best-suited for the application. Each style has its advantages and limitations.

            Image of Tregaskiss TOUGH GUN CA3 robotic MIG gun with 45 degree neck
            Conventional guns can often access joints better and/or maneuver around tooling or fixturing that a through-arm gun can’t reach and may also be less expensive.

            Through-arm robotic welding systems have become more common, as more equipment manufacturers develop this style compared to conventional robots. Through-arm robotic welding systems, however, allow for the mounting of either a through-arm gun or a conventional one. In some applications, the latter is the better choice. 

            When choosing between the two, consider the available space and weld cell layout, joint access and the type of material being welded. 

            Conventional guns can often access joints better and/or maneuver around tooling or fixturing that a through-arm gun can’t reach. Conventional guns can also be less expensive and faster to install, although they do require proper cable management. They also require more space, so they aren’t typically the best choice in smaller weld cells. 

            Through-arm guns work well in applications where deep access to the part or fixture is necessary. Since they don’t have a mounting arm and take up less space, they also offer advantages in smaller weld cells. The design of the gun —with the power cable assembly running through the arm of the robot —manages excess cable slack, which typically helps them last longer than a conventional power cable.  

            TOUGH GUN TA3 Robotic Air Cooled MIG Gun
            Through-arm guns work well in applications where deep access to the part or fixture is necessary. 

            Choosing the right cable length 

            Selecting the proper cable length is critical for both types of guns and numerous factors impact the choice. These include wire feeder, the make and model of the robot, and robot articulation. 

            Having the right cable length helps prevent problems with wire feeding that can lead to downtime and unnecessary labor and/or part costs to address the issue. The wrong cable can further increase costs and downtime due to premature cable failure.   

            When using a conventional gun, a cable that is too short causes tension, which can result in components prematurely breaking down in the cable assembly. It can also cause the clutch or the robot to overload, which will send a collision detection signal that stops the robot — resulting in unnecessary downtime. A cable that is too long is also a problem, because it can get caught on tooling or result in extra weight that bogs down the mounting arm – potentially overloading the clutch. 

            With a through-arm gun, a too-short cable with visible tension also causes problems. Choose a cable that allows some slack for the robot arm to move around. But remember, too much slack can be as problematic as too little slack. 

            When choosing proper cable length for a through-arm gun, it’s important to know the robot make and model, the feeder make and model, and the measurements of the system. If any nonstandard equipment or tooling is mounted to the face of the robot, such as a gripper or a camera, this changes the thickness of the plate and therefore impacts the necessary cable length, requiring it to be longer. It is also important to know where the wire feeder is mounted relative to the robot casting to ensure proper cable length.

            Much of the same information is needed in choosing the right cable length for a conventional gun: robot make and model, feeder make and model. In addition, consider where the feeder is mounted on the robot or even remotely, as both will affect cable length. 

            For both types of guns, the feeder should be adjusted each time the cable is replaced to manage cable slack properly. Failing to properly adjust the wire feeder can result in a cable that is too tight or long for the given application, causing premature failure and potential damage to the robot or wire feeder.

            Fixing these issues at the start of the process can help avoid much greater downtime and costs later. 

            Key best practices

            Following some best practices can help extend power cable life, reduce downtime and improve productivity. Many of the best practices are related to the programming of the automated welding system. 

            Image of end of LSR unicable for through arm robotic welding guns with arrows demonstrating rotational movement
            When using a through-arm guns, choosing a rotating cable connection can help reduce stress on the system. 

            Oftentimes, cables fail because they were set up to fail — the system is asking too much of the cable. Make sure the robot doesn’t articulate too far in either direction, to avoid placing excess stress on the cable, whether it is a conventional or through-arm robotic gun. 

            It’s also important to limit the movements of axis five (bending) and axis six (rotation) to help extend cable life. The joints of the robot get smaller as they move from the base to the wrist. Use the larger joints nearer to the base as much as possible and rely on the smaller joints only when necessary to reach the weldment. 

            In addition, employ a cable management system when using a conventional gun to ensure there isn’t too much slack in the cable. With too much slack, the cable will rub on anything around it and possibly catch on fixturing. When a robot moves at production speed, it can break the cable or fixture. Cable management systems can take the form of a recoil with an adjustment knob and pulley that allows the maintenance personnel or welding operator to adjust the position (length) and tension of the power cable.   

            When using a through-arm gun, choose a rotating power cable connection to reduce the stress on the system. Conventional style unicables typically come with a crimped or solid connection, which limits rotational capabilities and produces torsional stress on the cable. Unlike conventional unicables, a power cable that incorporates a rotating power connection allows for stress-free rotation — and can ensure a longer cable life. 

            Reduce downtime with the right choice

            Without the right equipment — and proper system programming — downtime can cost significant time and money in robotic welding applications. Take care upfront to choose the right equipment, including the gun and power cable, to save time and money in the long run and keep the operation running smoothly. 

              Conventional Guns on Through-Arm Robotic Welding Systems: When to Make the Choice

              Conventional Guns on Through-Arm Robotic Welding Systems: When to Make the Choice

              Close up image of a MIG gun with sparks as bright as fireworks
              While the choice of gun is sometimes an afterthought, it can significantly impact efficiency, throughput and quality of the finished weld. Choosing the best option for the job up front is key.

              Through-arm robotic welding systems are becoming increasingly common in the industry, as more equipment manufacturers turn to the development of this style compared to conventional robots. However, there are some applications where it is better to use a conventional robotic gun for these systems, instead of the through-arm gun typically chosen.

              The good news is that most through-arm robotic welding systems allow for mounting either type of gun — providing more options and flexibility depending upon the needs of the application. And while the choice of gun is sometimes an afterthought, it can significantly impact efficiency, throughput and quality of the finished weld. Choosing the best option for the job up front is key. 

              Considerations in choosing robotic guns

              As the name suggests, the power cable assembly of a through-arm MIG gun runs through the arm of the robot as opposed to over the top of it like in a conventional gun. Because of this design, the through-arm gun style is often more durable, since the power cable is protected.  However, because conventional guns can be used on either type of system — a through-arm robotic system or a conventional robot — they can sometimes offer greater flexibility, and can be used with more robot makes and models. 

              There are numerous factors to consider when making the choice between a through-arm gun and a conventional robotic gun for a through-arm robotic welding system:

              • Available space and weld cell layout
              • Reach and access to weldment
              • Type of material being welded 

              Benefits of conventional guns

              Conventional style guns, which typically offer a longer neck, can provide more flexibility in accessing or reaching certain weldments, whereas through-arm guns may have difficulty reaching around fixturing or tooling in some cases. In applications where a through-arm gun is installed and it doesn’t reach the weldment as needed, a conventional gun can be swapped in for access purposes.

              In addition, conventional guns are often a good choice in smaller, more modular weld cells that feature short-armed robots. Through-arm guns may not work as well in these situations because there is not as much cable, and therefore the robot doesn’t have as much slack for articulation.

              Also, because of the way the cable lies in a conventional gun, the bend radiuses of the cable are much larger than in through-arm guns. When welding aluminum, for example, wire feeding is a major contributing factor to poor weld quality, and therefore tight bend radiuses are not recommended. This makes conventional guns a good option when robotic welding aluminum.

              Uptime and throughput are also critical in robotic welding applications, and maintenance is a key factor that impacts productivity, downtime and costs. Conventional guns often provide easier maintenance because everything is outside of the arm, allowing for parts to be changed or repaired quickly to minimize downtime. Another benefit of conventional guns is they tend to be more cost-effective to purchase and can be installed much faster — saving time and money in setup. 

              When to stay with a through-arm gun

              Through-arm guns provide their own advantages when matched with a through-arm robotic welding system. In applications that require plunging deeply into a fixture or part, a through-arm gun is often a better choice. Think of a through-arm gun as an extension of the robot arm. This extension allows it to access different areas within the part being welded, depending on the application.

              In addition, because the cables are more protected on a through-arm gun they tend to last longer overall, which helps reduce replacement costs. The through-arm design naturally protects the power cable and makes it less prone to snagging on fixturing, rubbing against the robot or wearing out from routine torsion.  

              Best practices for performance

              With either a conventional gun or a through-arm gun, there are some common best practices that can contribute to success in robotic MIG welding.

              First, it is critical that the cable is never under tension when using a through-arm gun, to help prevent premature cable failure. Cable tension is visible on a conventional style gun but not on a through-arm gun since the cable runs through the gun. This makes proper setup especially important with through-arm guns.

              In addition, it’s best to use a cable management system when using a conventional gun to ensure there isn’t too much slack in the cable. With too much slack, the cable will rub on anything around it and possibly catch on fixturing. When a robot moves at production speed, it can break the cable or fixture. Keep these factors in mind, along with joint access requirements and weld cell layout, when making the gun choice to help improve throughput and productivity. 


                Six Tips for Implementing Your Robotic GMAW Gun… and Getting the Most From It

                Six Tips for Implementing Your Robotic GMAW Gun … and Getting the Most From It

                As companies seek to gain a competitive edge, it’s not surprising that some turn to welding automation. It offers numerous advantages, including greater productivity, improved quality and cost savings compared to a semi-automatic welding operation. However, to gain the most out of the investment it’s important to follow some best practices in the weld cell. These considerations include the careful selection, installation and maintenance of gas metal arc welding (GMAW) guns.

                As with any type of welding equipment, the goal is to implement the GMAW gun in a manner that optimizes performance, reduces downtime and prevents the accrual of unnecessary costs. It is important to note that the considerations for achieving these benefits may vary depending on whether the robotic welding system uses a through-arm gun or a conventional-style gun. Following are some tips to help.  

                Image of a robotic welding MIG gun with sparks
                Implementing some best practices can help companies extend the life of the GMAW gun and consumables, and optimize performance and efficiency of an automated welding system — so they can get the most out of the investment.

                Tip No. 1: Choose a solid mount instead of a clutch

                All automated welding systems need some form of collision detection to minimize damage to the robot and the GMAW gun in the event of an impact. Today’s robots typically have built-in collision detection software, making it appropriate to use only a solid gun mount to connect and position the GMAW gun. In some cases, companies like the secondary insurance of using a clutch on robots featuring this software. Doing so, however, can add unnecessarily to the expense of the operation, increase weight on the front end of the robot arm and cause the tool center point (TCP) to be less repeatable. When possible, it is preferable to use a solid mount coupled with collision detection built into the robot, instead of a clutch.

                Solid mounts offer numerous advantages, especially for systems using a through-arm style gun. A solid mount can aid in achieving a more accurate TCP, providing greater repeatability for more consistent welds. They are also more cost effective and lighter weight, which allows for quicker movement and potentially better productivity. The use of a solid mount, in conjunction with a through-arm robotic GMAW gun, typically opens up the work envelope, so the robot arm can better access the weld joint.

                For systems with a conventional gun, a solid mount provides little benefit over a clutch in terms of opening up the work envelope or increasing productivity due to the position of the gun in comparison to the faceplate of the robot. 

                Tip No. 2: Use an air blast feature

                Air blast is an optional technology on GMAW guns that can help enhance gun performance. This feature can be factory-installed or retrofitted into a gun. Utilizing air blast when possible helps eliminate debris in the front part of the robotic GMAW gun, reducing opportunities for weld contamination that can lead to poor weld quality, costly rework and downtime.

                As the name implies, the air blast feature blows compressed air through the front of the gun to remove debris. It can be used with air-cooled robotic guns or water-cooled models.

                In addition to removing debris that can cause poor weld quality or contamination, air blast can help increase the time between cycles by removing spatter from the front of the gun. The air blast function can also be used to cool down the gun between weld passes, to help operations avoid going over the duty cycle limit when using air-cooled guns. 

                Tip No. 3: Utilize a simulation program

                Using simulation software to model the proposed weld cycle before selecting and implementing a robotic GMAW gun can help in achieving the best results with an automated welding system. While the goal with an automated welding system is often to move as quickly and freely as possible, it’s important to remember that it’s typically best to limit excessive robot movements, as it results in longer gun life thanks to reduced equipment stress. Simulation programs can be used to determine proper system setup, including TCP requirements and which nozzle and GMAW gun neck are best suited to get the desired joint access or angle.

                The reach and access of the gun neck, in particular, is an important factor in system movement and stress. Changing the neck angle from 22 degrees to 45 degrees, for example, can have a significant impact on robot articulation.

                This is where a simulation program is beneficial, since it can be used to determine the type of neck and the neck angle that are best for the application before making the investment. To gain optimum speed and performance from the gun, it may be as simple as slightly adjusting the height of the risers or tooling to gain better access to the weld and reduce stress on the gun. 

                Tip No. 4: Utilize a neck inspection fixture

                Among several peripherals that can be added to maximize system performance, a neck inspection fixture is one that can help improve throughput, minimize unnecessary downtime — and help gain the best performance from the robotic GMAW gun. A neck inspection fixture verifies that the gun neck is set to the intended TCP and allows the neck to be readjusted after a collision or if it becomes bent during routine welding.

                When neck adjustment is needed, the welding operator can simply adjust the neck to meet specifications. This helps prevent costly rework due to missed weld joints and can prevent the downtime it takes to reprogram the robot to meet the necessary welding specifications with a bent neck on the gun.

                In some cases, the welding operator can simply remove the bent neck and exchange it with a spare neck to get the system back online quickly. The damaged neck can be set aside for inspection later, resulting in less interruption to the weld cycle.

                Using a neck inspection fixture from day one of an automated welding system helps ensure a consistent TCP.

                Tip No. 5: Ensure proper gun and cable installation

                Choosing the right gun and cable for the application — and installing them properly — are key steps toward maximizing performance of the robotic GMAW gun. Consider the weld length, the required amperage and the type and thickness of material being welded when selecting a robotic GMAW gun.

                Air-cooled guns work well on lower amperage applications and high-volume welds. In heavy equipment manufacturing and similar industries, a water-cooled GMAW gun may be necessary to weld on thicker materials for longer periods of time. Water-cooled guns offer high amperages — usually up to 600 amps — at 100 percent duty cycle.

                Selecting the appropriate neck, power cable and other gun components can also have an impact on productivity and performance. Choosing the proper neck style and length for the application provides the gun with easy and complete access to the weld joint, which helps reduce weld defects and downtime for rework. Available neck angles typically range from 180 to 45 degrees, with varying lengths to accommodate most robotic welding applications. Necks can also be special ordered for custom TCP requirements when necessary.

                Tip No. 6: Conduct proper gun maintenance

                Image of a CA3 TOUGH GUN Robotic air-cooled gun
                Regularly check all connections on the GMAW
                gun to ensure they are tight and secure. Doing so
                helps prevent issues that can lead to weld defect
                and downtime.

                In addition, power cable style and length can also impact efficiency in robotic welding operations. For through-arm applications, the power cable is often sold in set lengths to match a specific model of robot, so the selection process is easier. For conventional style robots, it’s important to verify the exact length needed. Too long of a cable can easily kink or move during the welding process, while too short of a cable can stretch and shorten cable life. In both cases, it can result in downtime, premature cable failure and increased costs.

                Also, look for a sturdy power cable that can withstand UV damage from the arc and resist wear. Cables with quick-change features can extend cable life, simplify cable changeover and maximize arc-on time when installed properly.

                Choosing and properly installing the right gun and cable is just the beginning. Proper ongoing maintenance is also an important factor to optimize performance.

                Regularly check all connections on the GMAW gun to ensure they are tight and secure. Doing so helps prevent issues that can lead to weld defect and downtime. Tighten front-end consumables and check that all seals are in good condition. Also be certain the power pin is secure. While checking that welding cable leads are secure, look for signs of wear and replace them as necessary.

                Remove spatter from the GMAW gun nozzle regularly, ideally applying anti-spatter to protect against buildup. Implement a reamer when possible to minimize damage to the gun and front-end consumables. A reamer (or nozzle cleaning station) removes spatter from the nozzle bore and clears away debris that accumulates around the diffuser during welding, resulting in longer life of the consumables and higher weld quality. The reamer can be programmed to run between welding cycles — either during part loading or transfer — so it does not add to the overall cycle time per part.

                In addition, track the life span of the GMAW gun liner and replace it prior to failure. Replacement liners should be trimmed to the appropriate length using a liner gauge.

                Automated welding operations that are larger in size may need to do more frequent preventive maintenance. It’s especially important for companies that complete large weldments on thick materials because they stand to have greater costs and downtime for rework in the event of gun failure. 

                Optimize the system

                Automated welding systems add speed, accuracy and repeatability to the welding operation. They can help companies increase productivity and reduce costs in a relatively short period.

                Implementing some best practices can help companies extend the life of the GMAW gun and consumables, and optimize performance and efficiency of an automated welding system — offering them the most out of the investment.