Support mandrel for expansion device

A support mandrel 62 having a cylindrical body 64 which provides a mounting for selectively extendable and retractable keys 66, 67, the larger upper set of keys 66 providing selective engagement for the expansion comes (33) to allow the cones (33) to be pushed through the completion (10), whilst the smaller lower set of keys 67 serve to centralize the cones 22 on the mandrel. The keys 66,67 extend through windows 68 in a cylindrical housing 70 which is initially restrained in a position relative to the body 64 illustrated by restraining keys 72 which abut the upper end of a ratchet ring 74 pinned to the key housing 70, ensuring that the keys remain retracted to allow the mandrel to safely pass through the valve (24).