Method and apparatus for locking a subsurface safety valve in the open position
US4574889A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 11, 1985 |
| Grant date | Mar 11, 1986 |
| Priority date | — |
| Expiry date | Mar 11, 2005 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B2200/05
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A method and apparatus for locking out a subsurface well safety valve in the open position in which the valve includes a housing having a bore and at least one downwardly directed shoulder adjacent the bore with a valve closure member in the bore moving between open and closed positions, and a flow tube telescopically movable in the housing for controlling the movement of the valve closure member. The method includes engaging the flow tube from the bore, moving the flow tube towards the open position, and from the inside of the bore making one or more outward indentations in the flow tube at a predetermined location whereby the indentations will engage a downwardly directed shoulder on the housing thereby preventing the flow tube from moving through the closed position. The indentations may be made around the outer circumference of the flow tube, circularly positioned, and at a predetermined distance from the top of the flow tube.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.