Importance

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Abstract

A torque break-out system for a top drive drilling unit in a drilling rig. The torque break-out system includes a splined sub which is connected to a tubular member of the top drive drilling unit. A collar is positioned circumferentially around the splined sub. The collar has a plurality of interrupted splines in reciprocal relationship to interrupted splines on the splined sub. The collar is positioned by a pivot member having a pair of arms rotatably connected to the collar and a lift cylinder connected to the pivot member. The lift cylinder positions the pivot member between a first position in which the interrupted splines of the splined sub and the collar are not in substantial horizontal alignment and a second position in which the interrupted splines of the splined sub and the collar are in substantial horizontal alignment. The system includes a back-up wrench assembly having a vertical opening through which the drill string is received. A pair of extendible rams are attached to the back-up wrench assembly. A plurality of dies are attached to the rams. The rams are capable of extending towards the drill string so that the drill string is grippingly engaged by the plurality of dies. A torque member is non-rotatably connected to the back-up wrench assembly and to a cylinder pivot member. Rotation of the top drive unit relative to the drill string is accomplished by positioning the collar such that the interrupted splines of the splined sub and the collar are in horizontal alignment with each other.

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First Claim