Subsea manifold stab with integral check valve
US6009950A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 5, 1998 |
| Grant date | Jan 4, 2000 |
| Priority date | — |
| Expiry date | Mar 5, 2018 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B33/038
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A stab for a gas-lift injection line is disclosed which includes a built-in check valve to exclude seawater as the stab is being delivered to the subsea manifold. The check valve can be a spring-loaded poppet which can be pressure-balanced with the surrounding hydrostatic forces, or alternatively, preloaded with the use of a pressurized chamber working in conjunction with a biasing spring to hold the check valve in the closed position during delivery. After insertion of the stab into the subsea manifold, the gas flow begins in the stab, which overcomes the forces of the spring and/or pressurized compartment to push the check valve into the open position to allow gas-lift flow through the manifold and down the annulus into the gas-lift valves in the well. Bypass flow passages are incorporated into the plug to provide an additional force to hold the plug in the open position once the gas-lift pressure is applied so as to prevent chattering of the check valve component in the stab.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.