Abstract: A method and apparatus for tightening a screw connection having a motor-operated screwdriver unit, wherein the angle of rotation and the torque are determined during the tightening to be able to stop the tightening process on reaching a desired tightening tension. An increase in the torque over the angle of rotation is determined by a determination device in a first tightening region and a change in the increase in the torque over the angle of rotation is determined in a second, following tightening region, with the screwdriver unit being stopped by a control device on reaching or exceeding of a maximum permitted change in the increase and/or of a change speed that is determined with reference to the increase that occurred in the first tightening region.

Abstract: The invention relates to a device for determining the actual state and/or the remaining service life of a construction, materials-handling and/or conveyor machine, having a plurality of sensors provided on the construction, materials-handling and/or conveyor machine for recording various state information, a recording unit connected to the sensors for gathering the recorded state information, a central unit able to be connected to the recording unit for evaluating the gathered state information and determining the actual state and/or the remaining service life from the gathered state information, and a display device for displaying the determined actual state and/or the determined remaining service life, wherein the sensors comprise various sensor types for recording at least two different categories of information from the group comprising component oscillations, lubricant properties, component and/or lubricant temperature and drive loading and the central unit is designed to ascertain the actual state and/o

Abstract: A method and apparatus for tightening a screw connection having a motor-operated screwdriver unit, wherein the angle of rotation and the torque are determined during the tightening to be able to stop the tightening process on reaching a desired tightening tension. An increase in the torque over the angle of rotation is determined by a determination device in a first tightening region and a change in the increase in the torque over the angle of rotation is determined in a second, following tightening region, with the screwdriver unit being stopped by a control device on reaching or exceeding of a maximum permitted change in the increase and/or of a change speed that is determined with reference to the increase that occurred in the first tightening region.