METHOD OF MAKING A SEAMLESS HOT-FINISHED STEEL PIPE, AND DEVICE FOR CARRYING OUT THE METHOD

摘要

The invention relates to a method of making a seamless hot-finished steel pipe (16), in which originating from a billet (1) heated to a shaping temperature, a first shaping produces through a piercing step a thick-walled hollow ingot (8) which is subsequently elongated in a second shaping step at same temperature through rolling accompanied by a change in diameter and wall thickness to form a tube (shell), and from which a finished pipe is produced in a third shaping step through reduction rolling, with the method being characterized in that the second and third shaping steps defined by rolling are replaced by one shaping step in the form of a radial forging process using an internal tool (11) inserted in the hollow ingot (8) and at least two forging jaws of a forging machine (10) which act on the outer surface area of the hollow ingot (8), wherein the hollow ingot (8) is turned and axially advanced in a clocked manner in the idle stroke phase of the forging jaws.