Patent ID: 7413023

Claim:
A wellhead seal unit for use in a subsea well, the unit comprising: a tubular body engageable in a work string, the body having an axial through passage; and a sleeve mounted on the body through which the body can rotate and reciprocate axially relative to the sleeve; an inner surface of the sleeve including one or more seals, sealingly engageable on an outer surface of the body; an outer surface of the sleeve including a ram area against which one or more rams of a blow-out preventer are sealingly engageable; and wherein the sleeve includes releasably engageable means to releasably engage the sleeve to the body to restrict rotation and axial reciprocation of the body relative to the sleeve, the releasably engageable means being releasable when the unit is located in the blow-out preventer rams and the rams sealingly engaged to the sleeve outer surface, to thereby permit rotation and axial reciprocation of the body relative to the sleeve.