Dry hole wire core barrel apparatus
US3930679A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 11, 1974 |
| Grant date | Jan 6, 1976 |
| Priority date | — |
| Expiry date | Apr 11, 1994 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B31/18
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
Wire line core barrel apparatus that includes a wire line core barrel inner tube assembly movable through a drill stem to be seated in a latched core taking position adjacent the drill stem core bit, and a main overshot assembly that is coupled to a lowering overshot assembly for lowering the inner tube assembly and alternately coupled to a retracting overshot assembly for withdrawing the inner tube assembly. The inner tube assembly includes a generally annular overshot coupling member secured to a latch release tube that is mounted on a latch body to retract a pair of latches when said tube is moved axially outwardly relative the latch body, and an overshot coupling rod secured to the latch body and extended through the coupling member. The lowering overshot assembly has a lock coupling for releasably couplingly engaging the coupling rod that upon pulling on the lowering assembly with more than a given force will release coupling engagement of the lowering with the coupling rod. The retracting overshot assembly has a collet that will couplingly engage the coupling member upon lowering the retracting overshot assembly, and that upon withdrawing the retracting overshot assembly move…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.