GB856475A - Storm choke for wells - Google Patents

Abstract

856,475. Wells. CAMCO Inc. May 6, 1959 [Nov. 17, 1958], No. 15506/59. Class 85. A choke for installation in a well conduit and adapted to close the conduit in the event of excessive flow through the conduit, comprises a choke tube 15 axially slidable as a result of differential pressures at its ends against the opposing force of a spring 19, and a closure member 20 adapted to close the constricted passage through the tube after a given sliding movement of the tube. The tube is slidable within a housing 5, 6, 7 which is screwed into a hangar 3 sealed to this conduit by wings 4. The tube has a rib 14 which limits the sliding movement of the tube and which forms a dashpot in conjunction with the chamber 11, 12. The closure member is hinged to a member 21 engaging openings in the housing, and is so dimensioned that under normal flow conditions it is held against movement between the housing and an extension 18 of the tube. Abnormal flow, which is due to breakage of the conduit above the choke, causes the tube to move upwardly and when the movement is sufficient the closure member is released and moved by the flow of the fluid to seat on the extension to close the conduit. After the conduit has been repaired the tube is moved to the position shown by operating a valve 10 by wire line to balance the pressures above and below the choke, or by pushing the tube downwardly.