Method of gripping tubular members during forming operations and associated apparatus
US5848546A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 27, 1996 |
| Grant date | Dec 15, 1998 |
| Priority date | — |
| Expiry date | Nov 27, 2016 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB21D11/02
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A method of gripping a metal tubular member during a forming operation to resist damage to the gripped ends and reduce scrap, includes providing an outer tool having a recess structured to receive an end of the tubular member, inserting a resilient mandrel into the end of the tubular member and inserting the tubular member end into the recess. A compressive force is applied to the resilient member in a direction aligned generally axially of the tubular member to establish transverse expansion of the resilient member in order to clamp the tubular member end between the mandrel and the outer tool recess. The tube may be stretched beyond the yield point and formed while so clamped, after which the compressive force is removed so as to facilitate withdrawal of the formed tube. In one embodiment, the mandrel may consist of a composite which may have a lower durometer hardness inner portion and higher durometer hardness outer portions. In another embodiment, a substantially rigid mandrel is received within the tube end and an annular resilient sleeve is positioned on the outside of the tube end. The method may be used for a wide variety of purposes including forming structural vehicular …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.