Patent · US Expired

Double shearing rams for ram type blowout preventer

US6244336A · kind A · utility

60Cited by
16References
19Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMar 7, 2000
Grant dateJun 12, 2001
Priority date
Expiry dateMar 7, 2020

Classification

  • Technology area (CPC E)Fixed Constructions
  • CPC primaryE21B29/08
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

Double shearing rams designed for use in a standard ram-type blowout preventer used in oil and gas drilling and workover operations are disclosed. The double shearing rams include an upper shear ram and a mating lower shear ram. The upper shear ram includes an upper cutting blade and a lower guide blade vertically spaced to form a cavity therebetween. The cavity is sized to receive the lower ram's cutting blade in close fitting engagement when the rams are closed. The upper shear ram has a primary cutting edge formed on its leading edge and a secondary edge vertically and axially displaced from the primary cutting edge. During shearing operations, initial movement of the shear rams allows the upper shear ram's primary cutting edge to cooperate with the lower shear ram's cutting blade to make an initial shear of the member or members in the blowout preventer's bore. Further closing of the shear rams allows the upper shear ram's secondary cutting edge to cooperate with the lower shear ram's cutting blade to make a second shear of any remaining member or members in the blowout preventer's bore. A plurality of guide pins positioned on the upper shear ram and the lower shear ram notched…

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