A drive device for a solid bowl screw centrifuge includes a motor for rotating a drum of the centrifuge, a transmission which is connected between the motor and the drum, and a cooling device for cooling the transmission during operation when the drum is rotating. The cooling device is an annular body which is fitted on the outside of the transmission and has an air guiding device that conducts air from farther outwards radially inwards onto a surface of the transmission.

A drive device for a solid bowl screw centrifuge includes a motor for rotating a drum of the centrifuge, a transmission which is connected between the motor and the drum, and a cooling device for cooling the transmission during operation when the drum is rotating. The cooling device is an annular body which is fitted on the outside of the transmission and has an air guiding device that conducts air from farther outwards radially inwards onto a surface of the transmission.

A torque sensing device capable of measuring the force exerted by a torque arm on a lever is positioned between the torque arm and the lever. The torque arm is connected to the pinion of a planetary gearbox for rotating the bowl and screw conveyer of a decanter centrifuge at different speeds. The torque sensing device measures the torque between the pinion gear and the planetary gearbox. The sensor can be connected to a controller which can reduce the flow of the liquid/solid mixture to the decanter centrifuge thereby/reducing the torque and avoiding substantial damage to the planetary gearbox.

A solid bowl screw centrifuge for processing drilling muds includes a rotatable drum and a rotatable screw. The centrifuge has a drive device for driving the drum and the screw with a drive motor as well as a gear assembly for producing a differential rotational speed between the drum and the screw when the centrifuge is in operation. A gear input shaft of the gear assembly is rotationally fixed by an overload lever arm that can be triggered in the event of a torque overload. The overload lever arm is directly and detachably connected with one end thereof and at a radial distance from the rotation axis of the gear input shaft to the gear input shaft or to a part that is connected thereto in a rotationally fixed manner. A method is provided for monitoring the torque on the gear input shaft.