Casing valve
US5425424A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 28, 1994 |
| Grant date | Jun 20, 1995 |
| Priority date | — |
| Expiry date | Feb 28, 2014 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B43/26
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
An apparatus and method for producing through a casing without perforation are disclosed. The casing can be rotated while it is cemented and includes a multiplicity of sliding sleeve valves. Each of the valves selectively covers a plurality of pistons, each of which preferably has a rupture disc mounted therein. A pressure-regulating device is provided in association with each rupture disc to ensure retention of sufficient internal pressure in the tubing such that all discs eventually burst without any short circuiting through the discs which ruptured earlier. The outward movement of the pistons acts to assist in fracturing the formation. Thereafter, the pressure used to rupture the discs aids in further channeling the fluid energy of the fluid rupturing the discs, as well as putting additional pressure on the movable pistons to further stress fracture the formation. As the piston is pumped outward, the grease that is held captive within the piston assembly is forced outward through a bladder. As the grease is pumped out, it displaces the cement slurry and flushes the face of the formation directly in front of the piston. Serrations on the end of the piston assembly concentrate the…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.