Patent · US Expired

Method and apparatus for prevention of over-pressurization of a pressure responsive device

US4349043A · kind A · utility

11Cited by
7References
1Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJun 6, 1980
Grant dateSep 14, 1982
Priority date
Expiry dateJun 6, 2000

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T137/7869
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

An apparatus and method are provided in which the apparatus is insertable along a pressure transmission conduit extending from a source point to a pressure responsive device, such as a safety valve in a subterranean well. The apparatus has a fluid passageway through a housing with inlet and outlet means for communicating the passageway to the transmission conduit. A frictionless ball valve head and seat means are disposed in the housing and across the passageway for selectively isolating pressure communication between members of the transmission conduit. Means, such as a plunger, are provided for shifting the ball valve head off of its seat, with piston means being carried by the plunger and including a piston head which is responsive to differential pressure for urging the plunger in a first direction to move the ball valve to its seat upon increase of pressure in the conduit above a predetermined value. Biasing means shift the ball valve away from its seat when pressure within the transmission conduit does not exceed a predetermined value, for normal operation of the pressure responsive device.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.