Connections for wellhead equipment

Abstract

A wellhead assembly is provided having a first tubular member, and a second tubular member at least partially extending over a first end of the first tubular member defining an annular space there between. An arcuate lock member such as a lock ring is located within the annular space. At least one load applying member penetrates the second tubular member and urges the arcuate lock member against the first tubular member. A lock nut is coupled to an inner surface of the second tubular member. A method for coupling the first tubular member to the second tubular member is also provided.

1 . A wellhead assembly comprising: 
 a first tubular member;    a second tubular member at least partially extending over a first end of the first tubular member defining an annular space there between;    an arcuate lock member located within the annular space; and    at least one load applying member penetrating the second tubular member and urging the arcuate lock member against the first tubular member.    
     
     
         2 . The wellhead assembly of  claim 1  further comprising a lock nut coupled to an inner surface of the second tubular member, said lock nut overlapping at least a portion of said arcuate lock member.  
     
     
         3 . The wellhead assembly of  claim 2  wherein the arcuate lock member comprises a first set of wickers and wherein the first tubular member comprises a second set of wickers, wherein when the at least one load applying member is urging the arcuate lock member, the first set of wickers mesh with the second set of wickers.  
     
     
         4 . The wellhead assembly of  claim 3  wherein the first set of wickers is complementary to the second set of wickers.  
     
     
         5 . The wellhead assembly of  claim 3  wherein the arcuate lock member is a segmented lock ring.  
     
     
         6 . The wellhead assembly of  claim 5  wherein the segmented lock ring comprises a plurality of segments.  
     
     
         7 . The wellhead assembly of  claim 6  wherein a fastener urges each of said plurality of segments against the first tubular member.  
     
     
         8 . The wellhead assembly of  claim 6  wherein a segmented lock ring segment comprises a slot extending to an edge of the segment and to an outer surface of the segment and wherein said at least one load applying member penetrates said slot.  
     
     
         9 . The wellhead assembly of  claim 8  wherein the fastener interlocks with the segment.  
     
     
         10 . The wellhead assembly of  claim 9  wherein the slot comprises a wider section and a narrower section over the wider section and extending to the outer surface of the segment defining a dove tail geometry slot geometry in cross section.  
     
     
         11 . The wellhead assembly of  claim 10  wherein the load applying member comprises a tip section having a width smaller than the width of the slot wider section and greater than the width of the slot narrower section and a neck portion having a width narrower than the width of the slot narrower section, wherein the load applying member tip is slidably fitted in the slot wider section and the load applying member neck is slidably fitted in the slot narrower section interlocking the load applying member to the segment.  
     
     
         12 . A method for interlocking a first tubular member with a second tubular member comprising: 
 mounting the second tubular member over the first tubular member; and    coupling a load applying member on the second tubular member urging an arcuate lock member against the first tubular member.    
     
     
         13 . The method of  claim 12  further comprising coupling a lock nut on the inner surface of the second tubular member overlapping at least a portion of said arcuate lock member.  
     
     
         14 . The method of  claim 13  wherein the arcuate lock member comprises a first set of wickers on its inner surface and the first tubular member comprises a second set of wickers on its outer surface and wherein coupling comprises meshing the first set of wickers with the second set of wickers.  
     
     
         15 . The method as recited in  claim 14  wherein the arcuate lock member is a segmented lock ring.  
     
     
         16 . The method as recited in  claim 15  wherein the segmented lock ring comprises a plurality of segments.  
     
     
         17 . The method as recited in  claim 16  further comprising interlocking the load applying member with the segment prior to coupling.  
     
     
         18 . The method as recited in  claim 13  wherein coupling comprises threading the load applying member on the second tubular member.