Retrieval tool with slips for retrieving bottom hole assembly during casing while drilling operations
US7845431B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 22, 2008 |
| Grant date | Dec 7, 2010 |
| Priority date | — |
| Expiry date | Feb 4, 2029 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B23/14
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A casing-while-drilling bottom hole assembly is releasably connected with a casing string. A retrieval tool is run into the casing string and latched to the bottom hole assembly. Slips are mounted to the retrieval tool, the slips being retracted during running in. Differential pressure moves the retrieval tool and bottom hole assembly upward, and the slips engage the casing string to prevent downward movement if the pressure differential drops too low. A flow passage extends through the retrieval tool and the bottom hole assembly. A check valve in the retrieval tool allows downward flow through the flow passage but prevents upward flow, so that fluid may be circulated through the retrieval tool and bottom hole assembly while suspended with the slips.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.