Patent ID: 6386291
Filing Date: 2002-05-14
Classification: E21B

Abstract:
A subsea well assembly comprising:a first wellhead housing (26) secured to a first string of pipe (14) which is cemented into earth formations, said wellhead housing (26) having a sidewall with a plurality of flow ports (29), said housing having an internal landing profile (46); a second wellhead housing (32) secured to a second string of pipe (30) which extends through said first string of pipe (14), said second wellhead housing (32) having an external profile (47) which is landed on said internal landing profile (46) and is supported within said first wellhead housing (26), said first and second wellhead housings defining an annular space (33) which communicates with said flow ports (29) of said first wellhead housing (26), and with a return path between said first and second strings (14, 30) of pipe; a retrievable seal assembly (50), including a seal (51) disposed at least partially in said annular space (33), said seal assembly (50) characterized by being selectively capable of being placed in said annular space (33) such that said seal (51) is above said flow ports (29) for allowing cement returns from said return path between said first and second strings of pipe (14, 30) to exit said first wellhead housing (26), and of being placed such that said seal (51) is below said flow ports (29) for sealing said annular space (33) from formation water flow between said first and second strings of pipe (14, 30); means controllable from a vessel (200) location for forcing said seal assembly (50) downward in said annular space (33) until said seal (51) is below said flow ports (29); and means controllable from a vessel (200) location for retrieving said seal assembly (50) from said annular space (33).