Pressure-retaining seals useful in wellheads

Abstract

High pressure seals for pressure control fittings are disclosed, where such pressure control fittings are located at a wellhead, for example. Embodiments of cam lock seals, a spring-driven ball race seal and wedge seals are disclosed.

We claim: 
     
         1 . A pressure-retaining seal, comprising:
 a generally tubular adapter having first and second adapter ends, the second adapter end providing an adapter sloped surface;   a generally tubular pressure seal assembly having first and second assembly ends and a longitudinal centerline, the centerline defining an axial direction parallel to the centerline; and   the first assembly end providing a seal receptacle, the second adapter end and the seal receptacle further each providing cooperating abutment surfaces, the cooperating abutment surfaces forming a pressure seal between the second adapter end and the seal receptacle;   wherein, when the second adapter end is received into the seal receptacle, translocation of at least one wedge towards the centerline engages each wedge onto the adapter sloped surface so as to restrain the adapter from axial displacement relative to the seal receptacle.   
     
     
         2 . The pressure-retaining seal of  claim 1 , in which the second assembly end is configured to mate with pressure-retaining equipment. 
     
     
         3 . The pressure-retaining seal of  claim 1 , in which the first adapter end is configured to mate with pressure-retaining equipment. 
     
     
         4 . The pressure-retaining seal of  claim 1 , in which the seal receptacle is formed on an interior portion of the first assembly end, and in which the seal receptacle is shaped for receiving the second adapter end. 
     
     
         5 . The pressure-retaining seal of  claim 1 , in which each wedge has a wedge surface, such that translocation of the at least one wedge towards the centerline engages each wedge's wedge surface onto the adapter sloped surface so as to restrain the adapter from axial displacement relative to the seal receptacle. 
     
     
         6 . The pressure-retaining seal of  claim 1 , in which each wedge is part of a wedge assembly, and in which the wedge assembly is configured to engage both the second adapter end and the first assembly end when the second adapter end is received into the seal receptacle. 
     
     
         7 . The pressure-retaining seal of  claim 1 , in which the cooperating abutment surfaces include machined surfaces. 
     
     
         8 . The pressure-retaining seal of  claim 7 , in which the cooperating abutment surfaces further include (1) a machined shoulder surface and a machined slope surface provided on the second adapter end, and (2) machined surfaces provided on the seal receptacle to mate with the machined shoulder surface and the machined slope surface on the second adapter end. 
     
     
         9 . A pressure-retaining seal, comprising:
 a generally tubular adapter having first and second adapter ends, the second adapter end providing an adapter sloped surface;   a generally tubular pressure seal assembly having first and second assembly ends and a longitudinal centerline; and   the first assembly end providing a seal receptacle, the second adapter end and the seal receptacle further each providing cooperating abutment surfaces, the cooperating abutment surfaces forming a pressure seal between the second adapter end and the seal receptacle;   wherein, when the second adapter end is received into the seal receptacle, translocation of at least one wedge towards the centerline engages each wedge onto the adapter sloped surface so as to displace the second adapter end further into the seal receptacle.   
     
     
         10 . The pressure-retaining seal of  claim 9 , in which a selected one of:
 (1) the second assembly end; and   (2) the first adapter end;   is configured to mate with pressure-retaining equipment.   
     
     
         11 . The pressure-retaining seal of  claim 9 , in which the seal receptacle is formed on an interior portion of the first assembly end, and in which the seal receptacle is shaped for receiving the second adapter end. 
     
     
         12 . The pressure-retaining seal of  claim 9 , in which each wedge has a wedge surface, such that translocation of the at least one wedge towards the centerline engages each wedge's wedge surface onto the adapter sloped surface so as to displace the second adapter end further into the seal receptacle. 
     
     
         13 . The pressure-retaining seal of  claim 9 , in which each wedge is part of a wedge assembly, and in which the wedge assembly is configured to engage both the second adapter end and the first assembly end when the second adapter end is received into the seal receptacle. 
     
     
         14 . The pressure-retaining seal of  claim 9 , in which the cooperating abutment surfaces include machined surfaces. 
     
     
         15 . The pressure-retaining seal of  claim 14 , in which the cooperating abutment surfaces further include (1) a machined shoulder surface and a machined slope surface provided on the second adapter end, and (2) machined surfaces provided on the seal receptacle to mate with the machined shoulder surface and the machined slope surface on the second adapter end. 
     
     
         16 . A pressure-retaining seal, comprising:
 a generally tubular adapter having first and second adapter ends, the second adapter end providing an adapter sloped surface;   a generally tubular pressure seal assembly having first and second assembly ends;   the first assembly end providing a seal receptacle, the second adapter end and the seal receptacle further each providing cooperating abutment surfaces, the cooperating abutment surfaces forming a pressure seal between the second adapter end and the seal receptacle; and   at least one wedge surface;   wherein, when the second adapter end is received into the seal receptacle, sliding contact of the at least one wedge surface against the adapter sloped surface displaces the second adapter end further into the seal receptacle.   
     
     
         17 . The pressure-retaining seal of  claim 16 , in which the second assembly end is configured to mate with pressure-retaining equipment. 
     
     
         18 . The pressure-retaining seal of  claim 16 , in which the first adapter end is configured to mate with pressure-retaining equipment. 
     
     
         19 . The pressure-retaining seal of  claim 16 , in which the seal receptacle is formed on an interior portion of the first assembly end, and in which the seal receptacle is shaped for receiving the second adapter end. 
     
     
         20 . The pressure-retaining seal of  claim 16 , in which each wedge surface is part of a wedge assembly, and in which the wedge assembly is configured to engage both the second adapter end and the first assembly end when the second adapter end is received into the seal receptacle. 
     
     
         21 . The pressure-retaining seal of  claim 16 , in which the cooperating abutment surfaces include machined surfaces. 
     
     
         22 . The pressure-retaining seal of  claim 21 , in which the cooperating abutment surfaces further include (1) a machined shoulder surface and a machined slope surface provided on the second adapter end, and (2) machined surfaces provided on the seal receptacle to mate with the machined shoulder surface and the machined slope surface on the second adapter end. 
     
     
         23 . A pressure-retaining seal, comprising:
 a generally tubular adapter having first and second adapter ends, the second adapter end providing an adapter sloped surface;   a generally tubular pressure seal assembly having first and second assembly ends and a longitudinal centerline; and   the first assembly end providing a seal receptacle, the second adapter end and the seal receptacle further each providing cooperating abutment surfaces, the cooperating abutment surfaces forming a pressure seal between the second adapter end and the seal receptacle;   wherein, when the second adapter end is received into the seal receptacle, translocation of at least one wedge towards the centerline engages each wedge onto the adapter sloped surface so as to compress the cooperating abutment surfaces together.   
     
     
         24 . The pressure-retaining seal of  claim 23 , in which the second assembly end is configured to mate with pressure-retaining equipment. 
     
     
         25 . The pressure-retaining seal of  claim 23 , in which the first adapter end is configured to mate with pressure-retaining equipment. 
     
     
         26 . The pressure-retaining seal of  claim 23 , in which the seal receptacle is formed on an interior portion of the first assembly end, and in which the seal receptacle is shaped for receiving the second adapter end. 
     
     
         27 . The pressure-retaining seal of  claim 23 , in which each wedge has a wedge surface, such that translocation of the at least one wedge towards the centerline engages each wedge's wedge surface onto the adapter sloped surface so as to compress the cooperating abutment surfaces together. 
     
     
         28 . The pressure-retaining seal of  claim 23 , in which each wedge is part of a wedge assembly, and in which the wedge assembly is configured to engage both the second adapter end and the first assembly end when the second adapter end is received into the seal receptacle. 
     
     
         29 . The pressure-retaining seal of  claim 23 , in which the cooperating abutment surfaces include machined surfaces. 
     
     
         30 . The pressure-retaining seal of  claim 29 , in which the cooperating abutment surfaces further include (1) a machined shoulder surface and a machined slope surface provided on the second adapter end, and (2) machined surfaces provided on the seal receptacle to mate with the machined shoulder surface and the machined slope surface on the second adapter end.