Patent ID: 8387707

Claim:
A subsea well production assembly, comprising: a subsea wellhead; a well production casing assembly having one end connected to the subsea wellhead and comprising: an upper casing string; a lower casing string; and a tubular compensating member comprising an upper end connected to a lower end of the upper casing string, a lower end connected to an upper end of the lower casing string, and a steel body having a wall with undulation that are changeable between a compressed configuration and an elongate configuration; wherein the undulations in the wall comprise a series of helical slots along a length of the wall alternatingly formed about an inner circumference and about an outer circumference of the wall, each helical slot lying in a plane substantially perpendicular to an axis of the compensating member, the helical slots defining a series of cantilevers along a length of the body that are bendable when the body is axially compressed and that are bendable when the body is axially elongated; and the upper casing string is supported in tension, and the body transmits the tension to the lower casing string.