Automated welding packages, such as this one installed by SmartTCP, reduce the need for expert welders, speed manufacturing time, raise production volume, and improve finished quality.

When your demand increases but your supply of welders is limited, how can you keep your business growing? What if you have a multitude of parts but minimal quantities of each part that need welding, and manual welding is just too slow? The solution is to automate the process. However, until now automation technology wasn’t fast enough, flexible enough, or economically feasible to make this a viable alternative. But no longer: Automation now offers a solution for welding and fabricating operators.

Manufacturers with a high mix but low volume of parts have welding requirements that are not typical and require constant monitoring and control of the production process. High-mix/low-volume parts usually are not assembled accurately, as they are fitted without jigs. One should consider each component in the same batch as one-off production.  However, most robot-programming techniques available today — either on-line programming or off-line programming — are neither as accurate nor flexible nor fast enough to make this particular small-batch fabrication feasible.

Accommodating shape, size variations

For example, NPK Construction Equipment Inc. in Walton Hills, OH, manufactures attachments for heavy machinery used in construction, demolition and mining industry processes. During the past few years, NPK’s sales and production have grown exponentially – to the point that its manual welding process was bogging down production. The staff of master welders simply could not keep up and with fewer expert welders available to hire due to a worldwide shortage of welders, NPK had to find another solution. It needed a solution to increase production, improve quality and improve employees' working conditions.

Since NPK’s products range widely in size and shape and its inventory includes multiple part numbers with minimal quantities per part, its small-batch production process did not lend itself well to standard robotic welding systems. It needed a solution that would accommodate working with various part sizes and shapes, and that could adapt flexibly to each part’s welding requirement. It needed the sort of solution that could reliably weld all of its large complex parts quickly and accurately, but one that would require minimal robot programming time.

Getting with the programming

ACSS, a structural steel fabricator in Beaumont, CA, had a similar dilemma. With the current shortage of expert welders coupled with the spiraling costs associated with finding skilled labor, ACSS felt that automating its manual welding process was the next investment it could make that would give it a real return on investment, given the highly competitive climate of the structural steel industry. The key however was to find a solution that addressed its high-mix, low-volume part requirement — and the programming challenges associated with this mix. Typically, robot programming for welding is a complex and time-consuming undertaking that makes it uneconomical for small-batch production. 

Technological breakthroughs are moving automatic welding of small-batch production from a virtual model to reality. New technology is available for intelligent, robotic welding solutions for small batch fabrications. Now available are modular, flexible and automatic off-the-shelf manufacturing solutions that can be implemented in a wide range of manufacturing applications after a short setup. With these new advances an automation system can be designed specifically for small-batch production, and it can be extremely accurate, flexible and reliable, welding at a much faster rate. By combining hardware and software in a welding cell manufacturers can automate both the robot programming and the weld production of a company’s parts while realizing between 4 to 8 times savings in labor.

Manufacturers replacing manual welding processes with automation can reduce their welding times by as much as 80%. Additionally, by reducing its manual welding processes a manufacturer can address the challenges of attracting and maintaining qualified expert welders, a challenge created by the current worldwide welder shortage. Automation can reduce the need for expert welders, improve time to market, and increases production volume and quality.

Both NPK and ACSS have implemented such a solution using a combination of 6-axis articulate robots, 3-axis gantry units, 2-axis positioners in the first case and head-and-tail positioners in the second, welding power, controllers and software to provide the multi-dimensional movement required to weld a typical small batch production component accurately, fast and efficient. Automation now can turn welding robots into smart welding solutions that analyze 3D CAD data and execute the welding process.

Systems can be designed with as many as 16 axes in two or more working zones for efficient continuous welding. This gives manufacturers the flexibility to weld a high variety of parts ranging in size, geometry and welding technologies. Automation has come a long way and manufacturers looking for an easy to use, fast welding process for small batch fabrication now have the technology to automate without sacrificing flexibility.