A torque wrench comprises a split casing which can be divided to receive and grip pipes, each casing half comprising jaws which are synchronously movable to center and frictionally engage the pipe joints. The wrench has a split inner annulus which is mounted in and connected to a split intermediate annulus which is rotatably mounted in the split casing. The inner annulus is provided with at least two activable and displaceable clamping jaws in use, temporary and external transfer of a controlled torque is provided to the intermediate annulus. The torque is, in turn, transferred to the inner annulus by the aid of a connection, preferably in the form of pump cylinders, which at the same time activate and provide the displaceable clamping jaws with the necessary power. With a spinning motor, the wrench forms a combined spinning and torque wrench. With a back-up wrench, and mounted on a carriage the wrench assembly forms a complete roughneck.