There are many causes why one welding process may be chosen over another to manufacture welded tubing. Perhaps the most common method is high-frequency welding. To use high-frequency welding to make welded tubes, a high-frequency welding power source is activated.
Once the power source is activated, leads from the power source which is placed in close proximity to the formed but unwelded tube begin to emit high-frequency energy. This energy excites the molecules in the tube until a temperature level at which they can be joined is reached. At this point, the two heated edges of the unwelded tubing are forced together through another die and a weld is made. You can get more details about welded tubing and its manufacturing via www.webcotube.com/tubing-products/product-types/welded-tubing.
One of the reasons why high-frequency welding is so popular is because it is an established repeatable technology, it is cost-effective, and it can handle poor fit-up better, relative to the other tube welding processes. Furthermore, like nearly all large-scale welded tube manufacturing processes, it is performed in a continuous fashion allowing for high degrees of productivity.
Other welding methods are used in place of high-frequency welding for different reasons. Laser beam welding may be used for metals that are more difficult to weld than mild steel. Examples include titanium, stainless steel, and other non-ferrous alloys. Gas tungsten arc welding and plasma arc welding are sometimes used in place of laser welding because of their reduced equipment cost and complexity, however, they typically provide slower travel speeds and larger heat-affected zones.
Resistance welding is occasionally used instead of high-frequency welding for medium diameter carbon steel tubing. For welded steel tubing with thick walls, submerged arc welding is used.