Method for corrugating a metallic pipe
US5711177A · kind A · utility
3Cited by
6References
2Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jun 27, 1996 |
| Grant date | Jan 27, 1998 |
| Priority date | — |
| Expiry date | Jun 27, 2016 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB21D17/025
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A method of corrugating a metallic pipe which achieves an increase in the limit of tube expansion ratios. First, a heated part is formed by heating a local part of an outer periphery of a pipe in a circumferential direction by a high frequency coil. Next, the heated part is located within a forming surface of a forming die, and an axial compressive stress is applied to the pipe. Thus, the heated part is expanded while restricted by the forming surface. Therefore, even when the axial length of the heated part is increased, formability is stabilized and the tube expansion ratio can be raised.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.