Maximizing welder time with automation

KM MONT uses its PEMA TW5000-25 automated welding station to fabricate pressure vessels up to 4.8 m in diameter and 22 m long.

Somewhere near Vrbas, Serbia, a skilled welder is still working because his employer invested in automation. But how?

That the employer in question, steel fabricator KM MONT in Petrovaradin, Serbia, employs about 75 skilled welders and about 300 workers total might intrigue some people. Also notable: The company’s new automated rotary pipe welding line, a PEMA TW5000-25 that includes a column and boom station and an assembly station, welds large pressure vessels much faster than the company’s manual welders ever could.

But probably the biggest point of interest is that the owner of KM MONT, Mladen Kukic, decided to invest in the welding cell not only because of its efficiency with many of its biggest jobs, but mainly because it would free those 75 welders to do other jobs that can only be accomplished manually.

In addition to large pressure vessels, KM MONT mainly fabricates, assembles, and welds parts made from carbon steel sheets and pipes, as well as some aluminum parts. The parts are used in products such as gas skids (for contaminant removal and temperature control), pipe bridges and bundles, industrial furnaces, air separators, seals, air ducts, filters, and assemblies for the liquid natural gas industry. The company also fabricates vessel piping and spools for different industries.

How It’s Done

The welding station has stabilizing arms that hold workpieces in place and rotate them. It’s no small task—the company’s pressure vessels range in diameter from 1.4 to 4.8 m and in length from 5 to 22 m.

The line uses two different weld heads—an SAW head (used commonly for carbon steel) and one that can do both types of gas metal arc welding, either MIG or MAG. KM MONT chose the dual-head arrangement to prepare for future jobs in which the company needs to weld materials such as stainless steel, for which MIG and MAG are ideally suited.

The machine can weld pieces up to 25 mm thick, though most of the company’s workpieces are 10 to 15 mm thick.

Of all the manual jobs that the company does regularly, the pressure vessels have routinely proved to be the most labor intensive, though the company is hard-pressed to say how many hours per vessel because each project varies so greatly. For the welding alone, Robert Payer, the man responsible for commissioning the machine, estimated that the PEMA unit is 25% to 30% faster than manual welding.

“The biggest point for KM MONT was … to make their welders free for other projects or for other parts where we cannot use automation,” said Payer, co-managing director of PH-MFLOW GmbH, the Austrian project management and support firm that oversaw the purchase and commissioning of the welding station for KM MONT. “There are always problems with good welders all over Europe, and the biggest issue was to get the welders out from the process.”

That was the initial prompt for KM MONT and PH-MFLOW—responding to the critical shortage of skilled welders, not only across Europe but across the world.

“KM MONT needed the skilled welders on other jobs, and we know that it [the shortage] will not become better in the next few years,” Payer added. “So, we knew that we had to do something. This was the initial prompt, I think—that we know that it will not become better in the next month or year.”

Kukic said that the PEMA line was a sizable investment for KM MONT, which was founded in 1999. However, what it enabled the company to do with its valuable skilled workforce makes the machine well worth the outlay. He said it’s difficult to measure productivity gains overall because each project is so different from the next; however, the welding line has provided another benefit.

“I think the biggest effect is the increase in the quality itself,” Kukic said. “With this machine, we can definitely increase the quality in the projects where we use it.”

Payer noted that the PEMA machine caused the company to completely redesign its production process for the pressure vessels. It’s taken some time for the company to perfect that process, but now that the staff has experience with the machine, it has become routine.

“This was completely new for KM MONT,” Payer said. “We started the project when Mr. Kukic decided to buy this machine; we also made a new design of the process. I think last year we revised it a little bit to make it a little bit smarter and smoother.”