Manual override for hydraulic gate valve actuators
US4213480A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 26, 1978 |
| Grant date | Jul 22, 1980 |
| Priority date | — |
| Expiry date | Dec 26, 1998 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T137/8275
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A double acting manual override mechanism for the hydraulic actuator of a subsea gate valve, and a visual indicator device for indicating the gate position. The gate is normally held open by hydraulic pressure and is moved by a spring to a fail closed position in the event of a malfunction. The override includes a drive nut threaded onto the valve stem and a drive sleeve which is telescoped on the drive nut and connected therewith by a series of splines. Spaced apart abutment surfaces are provided on the sleeve to limit axial movement of the drive nut on the valve stem in both directions. Rotation of the sleeve by means of an adapter is translated into rotation of the drive nut which contacts one of the abutment surfaces and thereafter effects axial movement of the valve stem to open or close the gate. The indicator device includes a watertight, transparent housing within which an indicator disc moves in response to movement of the gate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.