Process for installing a helical added thread in an internally threaded orifice for repairing the internal threads of the orifice
US5255423A · kind A · utility
1Cited by
10References
5Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Oct 8, 1991 |
| Grant date | Oct 26, 1993 |
| Priority date | — |
| Expiry date | Oct 8, 2011 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/49881
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
To repair the internal thread (2b) of a large diameter orifice, an added thread is screwed into the orifice in a form wound on a threaded part of the surface of a drum screwed into an internally threaded centering ring engaged in the entry part (2a) of the orifice (2). The thread is laid against the internal thread (2b) and fastened in place by installing a pin passing through the thread and engaged in the wall of the orifice (2). The process is used for repairing the internal threads of orifices (2) machined in the flange of a pressurized-water nuclear reactor vessel, allowing the vessel cover to be bolted down sealingly.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.