Patent ID: 8327943

Claim:
A wellhead apparatus, comprising: a wellhead member having a vertical bore for receiving an upper end of a string of conduit extending into a well, the bore of the wellhead member having a downward facing shoulder; a packoff bushing within the bore of the wellhead member and having an external upward facing shoulder below the downward facing shoulder, preventing upward movement of the packoff bushing within the wellhead member, the bushing having a vertical bore adapted to closely receive the upper end of the conduit, the bore in the bushing having a set of threads; an annular packoff seal within the bore of the bushing for sealing against an outer diameter of the conduit; a sleeve carried within the bore of the wellhead member, the sleeve having a threaded outer profile that is secured to the threads in the bore of the bushing; and wherein the sleeve isolates the bore of the wellhead member from high pressure fluid injected into the sleeve, the sleeve has a passage with a circumferential groove formed in the passage adjacent an upper end of the sleeve for allowing engagement with a lug of a running tool, and the sleeve has a plurality of slots formed in the passage extending from the upper end of the sleeve toward the circumferential groove, a portion of each of the slots intersecting with the circumferential groove to allow disengagement of the lug on the running tool when aligned with the one of the slots; and a vertical shoulder located adjacent to each slot within the circumferential groove for providing a reaction point for the lug on the running tool to rotate the sleeve during installation and retrieval, the shoulder being positioned closer to one of the slots than an adjacent slot such that when engaged by the lug during rotation while installing the sleeve, the lug will be misaligned with any of the slots, and when engaged by the lug during rotation to retrieve the sleeve, the lug will be aligned with one of the slots.