Annulus pressure operated closure valve with reverse circulation valve
US4064937A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 16, 1977 |
| Grant date | Dec 27, 1977 |
| Priority date | — |
| Expiry date | Feb 16, 1997 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B2200/04
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A closure valve for use in oil well testing is presented which provides a full opening flow passage therethrough, and which includes a reverse circulation valve. The closure valve is operated by a power mandrel which is responsive to well annulus pressure, and which is frangibly held in the open position until a predetermined pressure is applied to the fluid in the well annulus. The power mandrel is then frangibly released and moves the closure valve to the closed position. The power mandrel is then disconnected from the closure valve operating mechanism and continues to move to activate a circulation valve opening mechanism. The closure valve includes two normally open ball valves which are spaced apart to trap a sample of formation fluid therebetween when the ball valves are closed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.