Manufacturing process of seamless pipe

Hot rolled seamless tubes are generally produced on automatic tube rolling mills. The solid pipe blank is inspected and removed for surface defects, cut to the required length, centered on the end face of the perforated end of the pipe blank, and then sent to a heating furnace for heating and perforation on the perforator. When the perforation is continuously rotating and advancing at the same time, under the action of the roller and the head, a cavity is gradually formed inside the tube blank, which is called a capillary tube. It is then sent to the automatic tube rolling mill to continue rolling. Finally, the whole wall thickness is adjusted by the whole machine, and then adjusted by the sizing machine to meet the specifications. The production of hot-rolled seamless steel tubes using a continuous tube mill is an advanced method.

To obtain seamless pipes with smaller size and better quality, cold rolling, cold drawing or a combination of the two must be used. Cold rolling is usually carried out on a two-roll mill, and the steel tube is rolled in a ring-shaped pattern composed of a variable-section circular hole groove and a fixed conical head.