Apart from torque, the depth of insertion is another reference value which monitors the correct screwing of a fastener. The depth of insertion defines how deep the screw is inserted into the work piece. The automatic bit stroke features a
magnetic contact. A sensor detects the magnet during the up-and-down movement of the spindle and indicates the depth of insertion that has been reached. A measurement accuracy of +/-0,1 mm is possible.
In the case of a torque-rotation angle controlled fastening process, the depth of insertion is additionally checked before the torque threshold has been reached. The depth of insertion is thus another factor to monitor the correct fastening process. If the torque threshold is reached before the depth of insertion, the fastening process will be classified as “NIO” (not in order). In the case of a depth controlled fastening process, only the correct insertion depth of the fastener is checked.