A swivel seal assembly, a method for increasing the life of a swivel seal and a swivel

摘要

Methods and apparatus for providing enhanced seal life of a swivel seal assembly by decreasing the effective differential pressure across a given rotating seal. The differential pressure is decreased by providing a pressurised fluid on the low-pressure side of the seal at a predetermined fraction of the operating pressure of the swivel seal assembly. A preferred swivel seal assembly (10) utilises a washpipe (14) and a packing box (18) that are rigidly affixed to their respective conduits (11,12) such that misalignment and dynamic run-out is compensated for in the gap between the washpipe (14) and the packing box (18). A control system (40) monitors and regulates the pressurised fluid supplied to the assembly (10). <IMAGE>