Drill string shock absorber with improved pin type torque transmission means
US4210316A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 29, 1979 |
| Grant date | Jul 1, 1980 |
| Priority date | — |
| Expiry date | Jan 29, 1999 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B17/07
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A shock absorbing apparatus for use in an earth boring drill string is disclosed herein. The shock absorber is of the type having a mandrel reciprocally mounted for rotation with a tubular body; a sealed chamber between the tubular body and the mandrel containing pressurized fluid for absorbing load and shock. Torque is transmitted between the mandrel and body by pins which are inserted in cavities formed by grooves on the exterior of the mandrel and the interior of the body. Means are provided to prevent pin rotation and to prevent the pins from contacting the groove edges to provide improved loading and wearing characteristics of the pins.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.