Pipe end expanding or contracting process utilizing ironing
US4297867A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 29, 1979 |
| Grant date | Nov 3, 1981 |
| Priority date | — |
| Expiry date | Jun 29, 1999 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB21D41/00
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A process and a device for expanding or contracting the end of a pipe are disclosed. First an ironing die or punch is put over or into the end of the pipe. Then the end of the pipe is expanded or contracted by a rod form expanding punch or a tube form reducing die. Then, with this punch or die still in place, the ironing die or punch is pulled over or through the end of the pipe, so as to pinch the wall of the pipe between itself and the punch or die, and thereby the wall of the pipe is ironed so as to release any strains that may have been caused in it by the expanding or contracting process. Thereby more accurate pipe ends can be formed simply and reliably.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.