Subsea power fluid accumulator
US4649704A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 25, 1986 |
| Grant date | Mar 17, 1987 |
| Priority date | — |
| Expiry date | Jul 25, 2006 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB63C11/52
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
The present invention is directed to a pressurized fluid accumulator adapted to be connected to a subsea valve actuator on a drilling wellhead assembly, prior to lowering the combined assembly to the ocean floor. The apparatus of the present invention consists of a pressure compensated piston located in a first hydraulic cylinder. Movement of this piston causes pressurized hydraulic fluid to be delivered in sufficient volume to activate a subsea hydraulically-activated valve. The first piston is connected to and driven by a second piston contained in a second hydraulic cylinder. Charging and accumulation of pressurized hydraulic fluid in the first cylinder causes a nearly absolute vacuum to be developed under the second piston. The pressure differential between this vacuum and the prevailing sea pressure is used to move the first piston during delivery of the hydraulic fluid to the actuator of the hydraulically activated valve.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.