Helical stress relief groove apparatus and method for subterranean well drill pipe assemblies
US5535837A · kind A · utility
5Cited by
14References
12Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Jul 5, 1994 |
| Grant date | Jul 16, 1996 |
| Priority date | — |
| Expiry date | Jul 5, 2014 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B17/00
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
An apparatus and method are provided for enhancing fatigue and stress resistance properties of a subterranean well drill pipe string section by providing a helical groove near the pipe to tool joint weld. Stresses in and around the top portion of the pipe are redistributed to and absorbed by the helical groove region of the drill pipe string section, which has a relatively greater resistance to fatigue caused by bending and other stresses, thereby making the drill pipe string section less prone to fail due to rotational, tensile, and bending stresses.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.