The CMC-1 Cable Motion Compensator provides both depth and motion compensation for packages landed subsea. It works with wire rope, synthetic rope, or any steel tubular member. By varying cylinder size, it compensates any load which will be lowered.
Fitting between the deploying cable and the landing package, it works with any vessel or winch, including synthetic rope winches. The vessels and/or winches do not need to have their own motion compensation methods.
To the right/below the Cable Motion Compensator is shown in the Neutral Position, Vessel Down, and Vessel Up positions. Note the piston rod and hook stay at the same elevation. The cylinder moves up and down as the vessel goes up and down. The piston has the same size rod on each end exposed to the environment. It is automatically pressure compensated as the ocean water depth increases.