Seamless tube

    Seamed pipe is a pipe produced by split-flow die extrusion method (direct extrusion), while seamless pipe is manufactured by piercing extrusion method (indirect extrusion); although the appearance of seamless pipes is similar to that of seamed pipes, there are obvious differences in performance.

    The split-flow die extrusion will leave parting line indistinguishable to naked eyes on the product itself, but the parting line position will become the weakest point during the use of the product. This can lead to weakened product performance or fatigue failure. The seamless pipe is free from the trouble of parting line due to the piercing extrusion, and it is significantly better than the seamed pipe in terms of product strength and fatigue performance. This makes the seamless pipe mainly used in different functional parts, such as: fluid pressing parts, pneumatic/hydraulic parts, bicycle frames and shock absorption parts, etc.