Method of circulating while retrieving downhole tool in casing
US7845417B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 1, 2008 |
| Grant date | Dec 7, 2010 |
| Priority date | — |
| Expiry date | Feb 12, 2029 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B7/20
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
Retrieving a down hole tool at a lower end of a string of casing can be performed with drill pipe during a casing-while-drilling operation. The operator suspends the casing in the well from a drilling rig floor opening. A string drill pipe is lowered into the casing while the casing is suspended for engaging and retrieving the down hole tool. When circulation is desired, the operator secures a circulation tool to an upper end of the drill pipe, then lowers the drill pipe and the circulation tool to close off an upper end of an inner annulus between the drill pipe and the casing. The operator circulates fluid down the circulation tool and the drill pipe and back up an outer annulus surrounding the casing. The connection between the circulation tool and the casing allows the operator to reciprocate the casing.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.