Abstract: An apparatus for indicating critical torque load in a drill string of a propeller shaft driven rotary drilling machine comprising an input and an output section in axial alignment and drivingly connected so as to rotate conjointly; the input section has an input shaft and a spiral spline affixed thereto; the output section has a tube shaft assembly and an output shaft affixed thereto; an input bearing is provided for rotatably supporting the input shaft and allowing for longitudinal movement of the input shaft toward the output section under conditions of increased torque load; an input housing for receiving the input bearing is affixed to a base; a receiver nut having a complementary female spiral spline is a companion for the spiral spline and is operatively connected to the spiral spline to permit longitudinal movement of the input shaft toward the output section under conditions of increased torque load; a compression spring prevents longitudinal movement of the input shaft under conditions of constant to

Abstract: A tension indicator used on a guy line system of an inclined oilwell derrick, comprising a hydraulic compression load cell, a pair of interlocking U-shaped yokes housing the load cell between the bases of the U-shaped portions, a plunger connected to the load cell bearing against the base of one interlocking yoke, the load cell bearing against the base of the other interlocking yoke, a walking load binder mounted on the outer end of a first interlocking yoke and providing an initial tension load to the guy line system, a threaded nut and screw adjustment assembly affixed to the outer end of a second interlocking yoke and providing a finer adjustment of the tension provided by the walking load binder, a pair of attachment hooks rotatably mounted on the outer ends of the tension indicator device for inserting the tension indicator device between a set of intermediate chains connected in a guy line, and a calibrated pressure gauge directly attached to the load cell; whereby the interlocking yokes transfer a line

Abstract: A drilling rig load indicator for use on a mobile drilling rig of the type which is provided with means for applying a downward force to a drill string and bit and for applying a lifting force to raise the drill string and bit, and being further provided with a hydraulic pressure source which operates a plurality of hydraulic jacks to support and level the drilling rig. The drilling rig load indicator is composed of a hydraulic totalizer, a pressure indicator, and, a plurality of hydraulic pressure gauges. The hydraulic totalizer has an input side which is connected by means of conduits to the hydraulic jacks and an output side which represents the summation of the loads upon the hydraulic jacks. In the event that the conduits cannot be connected to the hydraulic jacks, the conduits may be connected to separate hydraulic load cells which are placed between the hydraulic jacks and the earth.