دیکشنری تخصصی مهندسی نفت - نسخه آنلاین

n: a jackup drilling unit in which the drilling rig is mounted on two cantilevers that extend outward from the barge hull of the unit. The cantilevers are supported only at the barge end. Com- pare keyway.

n: see keyway.

n: a slot in the edge of the barge hull of a jackup drilling unit over which the drilling rig is mounted and through which drilling tools are lowered and removed from the well being drilled. Compare cantilevered jackup.

n: a positive-type clutch that works by means of metal strips that fit into keyways.