TIEBACK ADAPTER FOR A SUBSEA WELL

摘要

An improved tieback system for a subsea well and an improved tieback adapter (20) for a tieback casing string connecting from a platform to a subsea well. The tieback adapter connects to the hanger (22) and to the top end of the inner tieback casing string (18) and includes adjustable means (30) for connecting between the hanger and the inner tieback casing string. A tool (84) for moving said hanger relative to a head (14) on the upper end of the outer tieback casing string (12) and relative to the inner tieback casing string (18) and for tensioning the inner tieback casing string is provided. The adjustable connecting means has a ratcheting latch means (40,64,66) allowing such relative movement between the two tubular mandrels of the adapter and means (40,70) for preventing movement of the inner tieback casing string relative to said banger against upward loads.