Patent ID: 8157018

Claim:
A method of making up a riser string from a rig, comprising the following steps: (a) providing a plurality of torque stations, each torque station including: (i) a wrench body that includes first and second end portions, and a drive head on the first end portion of the body; (ii) a high torque wrench operatively connected to the drive head for rotating a threaded bolt member at a first rotational speed under a high-torque condition; (iii) a low torque wrench operatively connected to the drive head for rotating the threaded bolt member at a second rotational speed that is a higher rotational speed than the rotational speed of the high torque wrench; (iv) a horizontal positioning mechanism for moving the drive head in a generally horizontal direction; and (v) a vertical positioning mechanism for moving the drive head in a generally vertical direction, which the vertical positioning mechanism can vertically position the drive head independent from operation of the high torque and low torque wrenches; (b) providing a controller that controls the plurality of torque stations, including the high torque wrenches, the low torque wrenches, the horizontal positioning mechanisms, and the vertical positioning mechanisms; (c) supporting a riser string on a drilling rig or platform, the riser string including a plurality of joints of riser sections; (d) placing an additional riser section above the riser string, additional riser section including a plurality of riser threaded bolt members; (e) the controller causing the plurality of drive heads to each engage one of the plurality of riser threaded bolt members; (f) the controller causing the plurality of drive heads to spin down their respectively engaged riser threaded bolt members, wherein, during the spin down process, the respective high and/or low torque wrenches turning their respective drive heads; (g) after being spun down, each of the plurality of riser threaded bolt members being torqued down to a desired torque by the respectively engaged high torque wrenches; (h) the controller causing the plurality of drive heads to disengage the plurality of riser threaded bolt members, and providing clearance for another section of riser to be made up to the riser string; and (i) lowering the riser string a distance so that a new section of riser can be made up to the riser string.