by Nestor Gula
Orbital welding shines in tube and pipe applications
Even though it has been done for many years, welding tubes and pipes is not a simple task. Unless the tube can be spun around, out of position welding is a challenge many welders, especially novices, face.
“Orbital welding is a controlled welding process,” says Alan Avis, president and CEO of Otto Arc Systems Inc. “Computers control all aspects of the weld.”
Orbital welding is well suited for repeat welding on pipes as once the operator has programmed the computer, the system will consistently do the exact same weld time and time again. Within the program, the operator can set many different parameters to recreate perfect welds each time, explains Avis.
When welding pipes, a big problem is welding upside down–the puddle of molten metal is affected by gravity and wants to drop out. “When you’re doing your three to six and your six to nine, you’ll actually have it where you’ll have to control the puddle from that falling out. You are typically not putting in as much heat or you will be feeding in more wire to help the weld puddle stay cooler.”
Out of position welding is a difficult skill to master, and with the current need for skilled workers, automated welding is stepping in to help, according to Shannon Cronkhite-Toth, a welding technologist at Liburdi Automation Inc.
“There is major integration with manual welding and orbital welding. Often you will see certified welders do some welding manually and then other welding is done with our product so that we have the best of both worlds.”
Orbital welding helps bridge the gap between manual and automated pipe and tube welding. “In some cases, there are applications where if it’s not done remotely with orbital welding equipment, then it can’t be done in general,” she explains. “In a nuclear facility there are some welding applications where you just wouldn’t want to have a human there welding manually because they are exposed to gamma radiation. In the past those repairs just would not be done.”
A manual welder would have to weld in short bursts spaced out over a long period of time to limit their exposure to the radiation. This might compromise the structure of the weld.
“Whereas, with orbital welding, and with our product, you can set up the welding equipment and then weld it remotely controlling it through a TV screen,” continues Cronkhite-Toth. “Welders can still utilize their skill sets by controlling the robot. They can manipulate as they would in person, but now they are out of harm’s way so the jobs are done more safely and more efficiently.”
The consistency of welds achieved by orbital welding on tubes and pipe is what makes this welding tool essential in the field. “You’re doing a very controlled weld that copies the same thing over and over,” says Avis.
“When you get into the pharmaceuticals, or semiconductor industries where you use fusion welding and there’s no wire, it is mandated that you have to use orbital welding because there are controls to the weld. You’re controlling every aspect of the weld much better than you can if you did it by hand.”
Orbital welding is a reliable joining process that supports fast, efficient and economic assembling in fabrication shops. SMT
