Patent ID: 8904839
Filing Date: 2014-12-09
Classification: B21B,B21C

Abstract:
1. A method of making a seamless steel pipe from a hollow block, the method comprising the steps of sequentially: engaging a mandrel through the block; gripping the mandrel relative to a rolling direction upstream of the block with an upstream gripper and displacing the mandrel and the block downstream by the upstream gripper in the rolling direction through a multiple-stand continuous rolling mill so as to convert the hollow block into a tube blank until the tube blank exits the continuous rolling mill in the rolling direction, all while still gripping the upstream end by the upstream gripper upstream of the continuous rolling mill; gripping the mandrel downstream of the continuous rolling mill and upstream of the tube blank with a downstream gripper; with the upstream gripper upstream of the continuous rolling mill, releasing the mandrel from the upstream gripper and displacing the mandrel and tube blank downstream to an extracting mill by the downstream gripper; pulling the tube blank off the mandrel with the extracting mill while holding the mandrel against synchronous downstream movement with the tube blank by the downstream gripper downstream of the continuous rolling mill; and transporting the mandrel back upstream for engagement through another hollow block.