Fatigue life enhancement of noncircular openings
US4934170A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 16, 1989 |
| Grant date | Jun 19, 1990 |
| Priority date | — |
| Expiry date | Feb 16, 2009 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB23P9/025
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A noncircular opening is formed in a material. A mandrel or mandrel and expansion sleeve are used for coldworking a circular region of the noncircular opening, and for forcing a hard metal insert into coldworking contact with the material immediately bordering the remaining portion of the noncircular opening. An insert may be placed within a slot to form with a circular closed end of the slot a substantially circular opening. An expansion sleeve is placed in the opening and an expansion mandrel is pulled through it, or an expansion mandrel is used alone in the opening, to coldwork the circular region of the opening. An insert may be placed within an opening and then a mandrel moved through an expansion sleeve placed in a circular opening in the insert, or a mandrel alone may be moved through the opening, to radially expand the insert and coldwork the material bounding the noncircular opening.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.