Patent ID: 6367551
Filing Date: 2002-04-09
Classification: E21B

Abstract:
A subsea well apparatus comprising:a tree having an axis, an axial passage registering with a string of production tubing and a tubing annulus passage; an internal tree cap within said tree, said internal tree cap having a top surface, an axial passage passing therethrough in communication with said axial passage of said tree, and a tubing annulus passage offset from said axial passage of said internal tree cap and being in communication with said top surface of said internal tree cap and with said annulus passage of said tree, said annulus passage of said internal tree cap forming a valve receptacle near said top surface; a riser assembly that lands on an upper end of said tree, said riser assembly having an axial passage in communication with said axial passages of said tree and internal tree cap and a tubing annulus port, said port being offset from said axial passage of said internal tree cap and being in communication with said annulus passage in said internal tree cap; and a shuttle valve within said valve receptacle that moves between open and closed positions to open and close said annulus passage in said internal tree cap.