Thanks for reading! We hope this article was helpful to you in understanding the differences between seamless and welded tubing.

Not ideal for thin wall large diameter tubes.

Because of this, seamless takes much more time to produce and can be more expensive than its welded counterpart. However, there are many more steps needed to manufacture seamless tubing. Additionally, seamless tubing often has a cleaner surface finish meaning it is less susceptible to pitting and corrosion.

Seamless tubing can contain higher pressure because it does not have the large stress concentration point that welded tubing has. This process may need to be repeated several times to achieve the size reduction needed. This machine uses a pair of rolling dies and a second mandrel to elongate and reduce the tube to size. Next, the mother tube is put through a pilger mill. The center of the hollow tube is supported during this process by a long rod known as a mandrel. Starting with solid round stock, the billet is first drilled through then heated and forced through a narrow die. To make seamless tubing, the first step is to form a seamless pipe known as a hollow/mother tube.

Thinner wall, large diameter applications.

Therefore, heavy wall tubing is less feasible as welded tubing. Also, the stainless material used to create welded tubing must be thin enough to roll effectively. The long welded seam causes a stress concentration point, reducing pressure ratings to 80% of comparable seamless tubing. The down side of welded tubing comes in the form of high pressure and heavy wall applications. Because welded tubing requires less processing, it is typically quicker to produce as well as lower in cost than seamless tubing. Welded tubing can also be produced with thinner walls on larger diameter tubes, compared to seamless tubing.

Welded tubing can even be drawn like seamless tubing to offer a better weld seam, and surface finish. Cold forming results in smoother finishes and tighter tolerances.