Summer 2009 Edition

Tip Success in Your Favor!

What to Know Before Automating Your Welding Operation

Like most things in life, automating your welding operation isn’t as simple as flipping a switch! It requires careful assessment of the current welding processes and a detailed plan to automate. Done properly though, it offers the potential for numerous benefits, like increased productivity, improved weld cosmetics, lower material costs via less overwelding, lower energy and manpower costs, excellent reliability, and a rapid ROI.

Whether you attain these advantages depends on how well suited your process is to automation in the first place. The variables determining suitability for automation include the part(s) to be welded, part volume, the facility, incoming power and personnel.

Parts should be easy to weld

Automated welding systems are built for speed and thrive on repeatability. Parts that present gap, fit-up and access challenges will quickly hobble an automated welding process, as will a part that requires intricate clamping and tooling to hold it in place. As a rule, the human welding operator will always perform better than a robot or fixed automation for parts where weld positions are obstructed or where a part requires precarious placement.

Instead, the parts you manufacture upstream from the automated welding cell should be as simple and consistent as possible so the robot can execute the weld at the same place over and over again (if the joint moves, the robot will not be able to weld it). A good way to determine if a part is suitable for automated welding is to supply the robot OEM or welding solution provider with a blueprint of the part that can indicate how repeatable it is. An electronic CAD drawing of the part, which the robot OEM can import into its simulation software, is even better. This drawing helps to visualize the quality of the planned weld and how the part and its tooling can be fine-tuned to optimize the automated welding process.

Another upstream factor you should consider prior to automating is your parts flow. If you want to implement automation to relieve a bottleneck at the welding cell, then you should be certain there are no delays in upstream part fabrication or rework required before sending parts to the welding cell. You also need to make sure that the person supplying the robotic cell can match the cycle time of the automated cell.

If these solutions aren’t possible, you may want to consider that some robot manufacturers offer automation solutions for upstream applications as well. These machines are equipped with sophisticated part recognition systems that can pick up parts, manipulate them to the correct orientation and deliver them to the automated welding cell. If you doubt the consistency and cycle time of your manual upstream processes, you might consider this more expensive option.

Justify automated solutions with high part volume

In order to justify an automation investment, you need to be sure the volume of parts you need to produce is high enough, as a robot’s key benefit is the ability to produce high volumes of quality welds. Realistically, however, if you are a small fabricator, you may not have an application with a high part volume. Still, your facility may be able to select two or three smaller volume applications and program a robot to weld those different parts instead.

Part volume is a critical factor in estimating the return-on-investment, as up to 75 percent of the cost of a semi-automatically welded component is the labor. Even if your facility will be producing the same number of parts, it may be able to justify the investment due to the amount of labor an automated welding process eliminates.

Evaluating the facility

You also need to factor in how much space you can devote to fixed automation and robotics, as the physical footprint of these solutions and the room needed for the flow of raw materials are greater than that of semi-automatic welding processes. Although welding automation can consume large portions of plant real estate, even small facilities can still make automation work by purchasing fewer pieces of automation equipment that are programmed to perform multiple tasks. You can facilitate this solution by outfitting robots with various toolsets that enable them to work on diverse jobs while occupying a smaller footprint.

Additional power sources and ventilation will probably be needed when integrating automated cells. The optimum power supply for automation is 480 volt three-phase. Your facility also needs to consider bulk delivery for both wire and gas. Instead of buying 40 lb. spools, for instance, you would need to purchase 600 or 900 lb. drums. In terms of gas delivery, the priority is to limit robot downtime, which can be achieved by investing in manifold systems that eliminate the downtime associated with frequent bottle change-outs.

You should consider working with a third-party integrator if you decide to implement automation. System integrators are knowledgeable about all aspects of the facility modifications necessary for automation, including important safety regulations that apply in the fabricator’s region, country or state, in addition to those specified by OSHA and RIA (Robotic Industries Association).

Supervision of the automated cell

Automation doesn’t necessarily imply complete independence from human insight and supervision. You should have a skilled welder to program the robot or fixed automation system and to troubleshoot the automated welding process as needed. If such a person is unavailable or a new hire is unworkable, you should be prepared to vet robot OEMs to determine the availability and costs associated with OEM-based training of your personnel. Some automation companies may offer deals that include training for high volume purchases, and you can expect this training to last one to three weeks depending on the certification level desired.

Prior planning prevents poor performance

Automating welding processes can dramatically increase production while at the same time decreasing labor costs and improving weld quality. Transitioning to automation, however, shouldn’t be done impulsively – automation is not suited to every facility or process. You need to develop a plan that accounts for a variety of factors, including the part to be automated, the layout of your facility, part volume and personnel. Failure to complete an upfront evaluation of the current semi-automatic welding process could result in an imperfect automation solution that requires constant “baby-sitting.” With meticulous evaluation of these aspects, however, you can transition to an automated process that requires only nominal supervision and generates a solid return on investment.