Apparatus and method for retrieving and/or communicating with downhole equipment
US5278550A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 14, 1992 |
| Grant date | Jan 11, 1994 |
| Priority date | — |
| Expiry date | Jan 14, 2012 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B47/01
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
Method and apparatus for fishing for and/or communicating with subsurface apparatus. In a preferred embodiment, a subsurface logging-while-drilling (LWD) or measuring-while-drilling (MWD) apparatus is placed in tandem with a drill string near the bottom of a borehole. The LWD apparatus includes a surface retrievable component such as a nuclear source carrier with a fishing head facing upwardly. The carrier is releasably secured within the LWD apparatus with means such as a shear pin. A wireline conveyed tool having a downwardly facing latching mechanism includes a downhole powered latch for telescopically extending beyond the fishing head, forcing a latching lug radially inwardly below the fishing head, and moving axially upward to latch the fishing head. Further upward latch movement causes the fishing head to move upwardly until the shear pin shears which releases the carrier from the subsurface apparatus. The wireline tool with the attached carrier is then brought to surface with the wireline cable. In a preferred embodiment, the subsurface apparatus includes a secondary coil within its tubular housing. A primary coil is provided on the wireline tool such that upon the wireline …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.