Mud flow heave compensator

摘要

A heave compensator is disclosed particularly adapted for use in compensating the flow through a riser pipe employed in offshore drilling apparatus for surges and ebbs produced in the flow therein by the rising and falling of the surface platform or vessel in relation to the ocean floor. A telescoping section substantially identical to that incorporated within the riser is carried by the floating platform or vessel at a location remote from the telescoping section of the riser. The compensating telescoping section is connected into the flow pipe on one end and closed at the opposite end. The two telescoping sections are disposed normal to the earth's surface whereby gravity tends to extend the compensating telescoping section. The two lower portions of the respective telescoping sections are interconnected by a flexible cable passing over a sheave carried by the platform or vessel. Such interconnection causes the compensating telescoping section to act in an equal and opposite direction to the telescoping actions of the telescoping section within the riser affording a constant compensation for changes in volume.