Seamless stainless steel pipe is manufactured with multiple combinations of different processes to the exact specifications needed by each of our customers,used in many applications, including the flow of gas, steam and liquid in harsh environments. Here are methods we mainly used.
Seamless stainless tube is made from metal bar using one of three methods, either piercing, extrusion or gun-drilling.
Piercing involves the controlled tearing of a hot metal bar and ironing of the sides of the hole and the method is limited to stainless steel alloys containing less than 12% chromium and size range from approx. 250 to 660 mm outside diameter.
Extrusion requires forcing the metal bar through a die over a mandrel. In addition, extrusion is the only process most suitable for long length seamless stainless steel coil tubing. Gun-drilling is believed to produce a higher quality product, but a more expensive method.
★The piercing of plug mill process