Patent · US Expired

Flapper type safety valve for subterranean wells

US4457376A · kind A · utility

89Cited by
6References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 17, 1982
Grant dateJul 3, 1984
Priority date
Expiry dateMay 17, 2002

Classification

  • Technology area (CPC E)Fixed Constructions
  • CPC primaryE21B2200/05
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

The disclosure relates to an improved flapper type saftey valve and valve housing for use in subterranean wells wherein the flapper valve is actuated from a horizontal closed position to a vertical open position by contact with a downwardly moving actuating sleeve. The top surface of the valve is elevated so that the bottom edge of the actuating sleeve always contacts the flapper valve at a position spaced from the axis of the pivot mounting, thereby assuring that the opening force applied to the flapper valve has a maximum moment arm in order to overcome any fluid pressure differential existing across the flapper valve. The valve is mounted in an eccentic bore on an eccentric mounting base and fully opened flapper valve provides maximum flow area through the valve.

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