Method for the preparation of subsequent partial wall thickness reductions for semi-finished pieces with cavities

摘要

The method involves preparing a prefabricated semi-finished steel pipe. A pipe wall region (2) is formed from peripheral wall (1) in semi-finished steel pipe by inner high pressure material deforming tool, according to measure of the desired wall thickness of pipe. The pipe wall region is subsequently removed from peripheral wall of steel pipe by ablative material processing method, so as to achieve desired wall thickness of semi-finished steel pipe.