Balanced isolation tool enabling clean fluid in tubing perforated operations
US4664184A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 31, 1986 |
| Grant date | May 12, 1987 |
| Priority date | — |
| Expiry date | Mar 31, 2006 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B43/1195
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
In tubing conveyed perforating well completion operations, shaped charge detonation is achieved by dropping a detonating bar in the tubing string. Velocity of the detonating bar is controlled by placing a column of standing fluid above the tubing conveyed perforating assembly. This apparatus and method isolate a column of standing fluid. Moreover, invasion by a well fluid is prevented to assure that the retardation characteristics of the standing fluid are not changed by invading well fluids. The apparatus includes a tubing string pressure isolation piston assembly slidable within a sleeve and a frangible closure disk broken by the detonating bar; the isolation tool further includes check valve means controllably venting fluid pressure across the valve means.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.