In-bore blow out preventer method and apparatus

Abstract

Existing BOP devices are complex electromechanical systems exploiting hydraulic activation of pipe rams and/or shear rams. With tens of thousands of oil wells in the 1,500 oil fields that account for 97% of global production of the over 40,000 oil fields identified to date and failure rates as high as 50% in disaster situations it is evident that a simpler, increased reliability approach would be beneficial to the oil and gas industries. It would be further beneficial if the BOP was automatic requiring no monitoring locally to the BOP or remotely from the rig or production facility.

1 . A method comprising:
 providing a frame attached to an object;   providing a compliant structure having a predetermined compression versus force characteristic, a first end of the compliant structure abutting the frame;   providing a pressure plate disposed at a second distal end of the compliant structure; wherein   at a first predetermined pressure the compliant structure is fully extended allowing flow of a fluid past the compliant structure; and   at a second predetermined pressure the compliant structure is fully compressed preventing flow of a fluid past the compliant structure.   
     
     
         2 . The method according to  claim 1  wherein,
 the object is at least one of a pipe and a pipe disposed within a bore. 
 
     
     
         3 . The method according to  claim 1  wherein,
 during compression the compliant structure increases in a dimension along an axis perpendicular to a central axis of the compliant structure. 
 
     
     
         4 . The method according to  claim 3  wherein,
 the increase in dimension results in the compliant structure expanding to fill the space between the object and a surface. 
 
     
     
         5 . The method according to  claim 4  wherein,
 the object is a pipe and the surface is the inner surface of bore within which the pipe is disposed. 
 
     
     
         6 . The method according to  claim 1  wherein,
 the compliant structure is a spring with a cross-section that is at least one of constant, varies in a predetermined manner, and has a cross-section that during compression results in the compliant structure dimension varying along an axis perpendicular to a central axis of the compliant structure. 
 
     
     
         7 . The method according to  claim 1  wherein,
 at least one of a predetermined portion of the complaint structure and the pressure plate have features to enhance an aspect of engagement of the at least one of with a surface. 
 
     
     
         8 . A device comprising:
 a frame;   a compliant structure having a predetermined compression versus force characteristic, a first end of the compliant structure abutting the frame;   a pressure plate disposed at a second distal end of the compliant structure; wherein   at a first predetermined pressure the compliant structure is fully extended allowing flow of a fluid past the compliant structure; and   at a second predetermined pressure the compliant structure is fully compressed preventing flow of a fluid past the compliant structure.   
     
     
         9 . The device according to  claim 8  wherein,
 the frame is attached to at least one of a pipe and a pipe disposed within a bore. 
 
     
     
         10 . The device according to  claim 8  wherein,
 during compression the compliant structure increases in a dimension along an axis perpendicular to a central axis of the compliant structure. 
 
     
     
         11 . The device according to  claim 10  wherein,
 the increase in dimension results in the compliant structure expanding to fill a space. 
 
     
     
         12 . The device according to  claim 11  wherein,
 the device forms at least one of a predetermined portion of a pipe and a predetermined portion of a pipe disposed within a bore. 
 
     
     
         13 . The device according to  claim 8  wherein,
 the compliant structure is a spring with a cross-section that is at least one of constant, varies in a predetermined manner, and has a cross-section that during compression results in the compliant structure dimension varying along an axis perpendicular to a central axis of the compliant structure. 
 
     
     
         14 . The method according to  claim 8  wherein,
 at least one of a predetermined portion of the complaint structure and the pressure plate have features to enhance an aspect of engagement of the at least one of with a surface.