公开(公告)号：US20170297069A1

公开(公告)日：2017-10-19

申请号：US15638535

申请日：2017-06-30

Applicant: SMS group GmbH

Inventor： Uwe MUSCHALIK ,  Jens MAGENHEIMER ,  Anna ROTT ,  Koos van PUTTEN

IPC: B21C25/04 ,  F16L9/02 ,  B21C25/08 ,  B21C23/08 ,  B21C23/21 ,  B21C23/20 ,  F16L9/22 ,  F15D1/02

CPC classification number: B21C25/04 ,  B21C23/085 ,  B21C23/205 ,  B21C23/217 ,  B21C25/08

Abstract: If a mandrel for extruding metal pipes, having two axially offset pressing surfaces with different radial embossing and having a transition region between these two pressing surfaces has a support surface in the transition region then the negative effect of narrowing, which arises owing to the mandrel shifting from a first pressing position, in which the first of the two pressing surfaces interacts with a die, to a second pressing position, in which the second pressing surface interacts with the die, can be minimized.