Change in length of drill string containing an instrument
US4143721A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 3, 1977 |
| Grant date | Mar 13, 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
Methods and apparatus are provided for enabling an instrument and a connected flexible line contained in a drill string to be left in the string while a pipe section is being added to or removed from the string, to thereby avoid the inconvenience and loss of time normally involved in removing the instrument and flexible line from the string on each such occasion. This result is preferably accomplished by initially threading the flexible line at the surface of the earth through a series of extra pipe sections positioned at a storage location adjacent the well, so that each of these sections can then be successively moved from that location to a position of connection into the upper end of the drill string with the flexible line already installed in the added section.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.