Subsea winch

摘要

A subsea winch is described. The subsea winch comprises a housing adapted to be attached to a well intervention system, the housing having an inlet and an outlet and at least one powered sheave arranged between the inlet and the outlet, the or each powered sheave having a surface adapted to form a frictional engagement with a cable passing between the inlet and the outlet via the at least one sheave. In use, a pull force pulling the cable in a downhole direction applied to the cable by a tool string being lowered into the well intervention system is increased by the winch such that the downhole pull force on the cable at the housing inlet is greater than the downhole pull force at the housing outlet.

主权项

1. A subsea winch comprising:
a housing adapted to be attached to a well intervention system, the housing having an inlet and an outlet; and a plurality of powered sheaves arranged between the inlet and the outlet, each powered sheave having a surface adapted to form a frictional engagement with a cable passing between the inlet and the outlet via the plurality of sheaves, the plurality of sheaves including a first sheave and a second sheave, the first sheave being located adjacent a well axis, the well axis being defined as a centerline of a well bore, the first sheave being arranged between the second sheave and the well axis; wherein, in use, a pull force pulling the cable in a downhole direction applied to the cable by a tool string being lowered into the well intervention system is increased by the winch such that the downhole pull force on the cable at the housing inlet is greater than the downhole pull force at the housing outlet.