Retrievable wedging system for coupling downhole devices into cased bore holes
This patent describes a retrievable wedging system for coupling a device to the interior of a cylindrical pipe comprising: a pair of arcuate top wedges for insertion between the device and the pipe; a first O-ring for disposition about the top wedges to couple the top wedges to the device; a pair of arcuate bottom wedges for insertion between the device and the pipe, the bottom wedges opposing the top wedges, whereby the top and bottom wedges cooperate to lock the device to the pipe when they are pressed together; coupling means for slideably coupling the bottom wedges to the device; retrieving means for disengaging the device from the cylindrical pipe and removing the top and bottom wedges and the device from the pipe, the retrieving means being arranged such that when the device is removed from the pipe, the retrieving means initially disengages the top wedges from the device and moves the device only after the top wedges have been disengaged but before the bottom wedges are moved. A method of releasably coupling a device to a bore hole casing and subsequently retrieving the device comprising the steps of: coupling a pair of bottom wedges to the bottom of the device and a pair of top wedges to the top of the device; inserting the device together with the top and bottom wedges into the bore hole and lowering the device until the bottom wedges contact the bottom of the borehole; setting the device by pushing the top wedges towards the bottom wedges to lock the device in place against the casing.
- Assignee:
- Electric Power Research Institute, Inc., Palo Alto, CA
- Patent Number(s):
- US 4840230
- OSTI ID:
- 5568488
- Resource Relation:
- Patent File Date: 14 Sep 1987
- Country of Publication:
- United States
- Language:
- English
Similar Records
Method and apparatus for running and retrieving logging instruments in highly deviated well bores
Earth boring assembly with drag pipe