Electrically insulative gap sub assembly for tubular goods
US5138313A · kind A · utility
77Cited by
9References
18Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Nov 15, 1990 |
| Grant date | Aug 11, 1992 |
| Priority date | — |
| Expiry date | Nov 15, 2010 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B47/13
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
An electrically insulative gap sub for inclusion in a drill string that consists of upper and lower threaded joint members, an inner sleeve connected to extend axially from the upper joint member, an outer sleeve connected to the lower joint member and extending in concentric spacing over the inner sleeve, and a plurality of differently configured, annular blocks of insulative gap material serially arrayed and filling the void in between inner and outer sleeves. The gap material is a high performance molded resin capable of transmitting the requisite torque, tensile and compressive forces encountered along the drill string.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.