Lengderegulerbar overgang for sammenkopling av brönnrörledninger, samt en fremgangsmåte og et verktöy i tilknytning til bruk av en slik overgang

摘要

There is disclosed an offshore well installation wherein a shoulder of a casing hanger body supported within a casing head on a platform at the water surface has been lowered onto a seat in the head so as to support a casing string anchored at its lower end to a mudline hanger in tension, the lower end of the hanger body being connected to the upper end of the string by an adjustable sub which is manpulated by a tool lowered through the hanger body and into the sub so as to adjust it from an extended position in which its shoulder is above the seat in the head to a retracted position in which the shoulder is seated on the head and the casing string is placed in tension.