Cavity lock system for a blowout preventer

Abstract

A blowout preventer (BOP) includes a ram supported within a cavity that is positioned crosswise to a central bore of the BOP. The ram is configured to move within the cavity between an open position in which the ram is withdrawn from the central bore and a closed position in which the ram is positioned within the central bore to thereby block a fluid flow through the central bore. The BOP also include a lock member that is configured to move between an unlocked position and a locked position in which the lock member is positioned within the cavity of the BOP and contacts the ram to thereby lock the ram in the closed position.

1 . A blowout preventer (BOP), comprising:
 a ram supported within a cavity that is positioned crosswise to a central bore of the BOP, wherein the ram is configured to move within the cavity between an open position in which the ram is withdrawn from the central bore and a closed position in which the ram is positioned within the central bore to thereby block a fluid flow through the central bore; and   a lock member configured to move between an unlocked position and a locked position in which the lock member is positioned within the cavity of the BOP to thereby lock the ram in the closed position.   
     
     
         2 . The BOP of  claim 1 , comprising an electronic controller configured to coordinate movement of the ram and the lock member, such that the lock member moves toward the locked position as the ram moves toward the closed position, after the ram reaches the closed position, or both. 
     
     
         3 . The BOP of  claim 1 , comprising a biasing member configured to bias the lock member toward the locked position. 
     
     
         4 . The BOP of  claim 3 , wherein the ram is configured to contact the lock member to thereby block the biasing member from driving the lock member to the locked position, while the ram is in the open position. 
     
     
         5 . The BOP of  claim 1 , wherein the lock member comprises a wedge shape. 
     
     
         6 . The BOP of  claim 1 , wherein the lock member is configured to rotate relative to the ram to move to the locked position. 
     
     
         7 . The BOP of  claim 1 , wherein the lock member is withdrawn from the cavity while the lock member is in the unlocked position. 
     
     
         8 . The BOP of  claim 1 , comprising an additional lock member configured to move between a respective unlocked position and a respective locked position in which the additional lock member is positioned within the cavity of the BOP and contacts the ram to thereby lock the ram in the closed position. 
     
     
         9 . The BOP of  claim 8 , wherein the lock member and the additional lock member are positioned on opposite sides of the cavity. 
     
     
         10 . The BOP of  claim 1 , wherein the lock member is configured to contact the ram while the lock member is in the locked position and while the ram is in the closed position. 
     
     
         11 . A cavity lock system for a blowout preventer (BOP), comprising:
 a lock member configured to move between an unlocked position and a locked position in which the lock member is positioned within a cavity of the BOP to enable the lock member to contact a ram of the BOP to thereby block withdrawal of the ram from a central bore of the BOP.   
     
     
         12 . The cavity lock system of  claim 11 , comprising an electronic controller configured to coordinate movement of the ram and the lock member, such that the lock member moves toward the locked position as the ram moves toward a closed position in which the ram seals the central bore, after the ram reaches the closed position, or both. 
     
     
         13 . The cavity lock system of  claim 11 , comprising a biasing member configured to bias the lock member. 
     
     
         14 . The cavity lock system of  claim 11 , comprising a hydraulic system configured to drive the lock member to the locked position, the unlocked position, or both. 
     
     
         15 . The cavity lock system of  claim 14 , wherein the hydraulic system comprises a lock cavity, the lock member comprises a piston portion positioned within the lock cavity, and the hydraulic system is configured to provide a fluid into the lock cavity to exert a force on the piston portion to drive the lock member to the locked position or to the unlocked position. 
     
     
         16 . The cavity lock system of  claim 11 , wherein the lock member comprises a wedge shape. 
     
     
         17 . A method of operating a cavity lock system for a blowout preventer (BOP), comprising:
 adjusting a ram from an open position in which a body of the ram is withdrawn from a central bore of the BOP to a closed position in which the body of the ram is positioned within the central bore of the BOP to thereby block a fluid flow through the central bore of the BOP; and   adjusting a lock member to contact the body of the ram while the ram is in the closed position to thereby lock the ram in the closed position.   
     
     
         18 . The method of  claim 17 , wherein adjusting the lock member comprises driving the lock member via a biasing member that biases the lock member into a cavity of the BOP. 
     
     
         19 . The method of  claim 18 , comprising maintaining the lock member in an unlocked position due to engagement between the ram and the lock member that overcomes a bias of the biasing member, while the ram is in the open position. 
     
     
         20 . The method of  claim 17 , wherein adjusting the lock member comprises providing a hydraulic fluid to drive the lock member into a cavity of the BOP.