Subterranean well pressure surging tool
US4393930A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 18, 1981 |
| Grant date | Jul 19, 1983 |
| Priority date | — |
| Expiry date | Mar 18, 2001 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B2200/05
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
An apparatus is provided for accomplishing pressure surging operations to remove particulates from the casing perforations and formation face of a subterranean well production zone. The apparatus includes two normally closed valve assemblies separated by a surge chamber maintained at atmospheric pressure. The uppermost valve assembly is connected to the end of a tubing string. A packer secures the lower valve assembly in sealing relationship to the casing bore. The lower valve assembly incorporates means for opening a flapper valve disposed between the atmospheric pressure surge chamber and the open bottom bore of the lower valve assembly. Such flapper valve is shiftable to an open position by movement of an actuator which responds to an increase in annulus fluid pressure. The opening of the flapper valve in the lower valve assembly produces a surge of production fluid from the formation and through the casing perforations into the atmospheric pressure surge chamber. The freed particulate matter is removed from the well by pressure actuation of an actuator sleeve in the upper valve assembly which moves upwardly to permit a spring-biased flapper valve to move to an open position. Th…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.