Change in length of drill string while instrument remains therein
US4153120A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 3, 1977 |
| Grant date | May 8, 1979 |
| Priority date | — |
| Expiry date | Oct 3, 1997 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B19/22
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A hole in the earth is formed utilizing a drill string containing an instrument connected by a flexible conductive line to a unit at the surface of the earth. During intervals when the length of the drill string is being changed, as by addition of another pipe section to the outer end of the string, the connection between the flexible line and the surface unit is temporarily broken, so that the instrument and line can be left in the drill string while the section is added and for ultimate reconnection to the surface unit through the added section. A portion of the flexible line may be wound about an element in the string, to be unwound therefrom each time that the string is lengthened, to thereby correspondingly increase the effective length of the line.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.