Schraubenkopf mit Markierungen für den Drehwinkel.

摘要

A fastener (1) which allows a user to easily utilize the Torque Angle Method to provide a predictable clamp load to a clamped element. The fastener (1) includes an externally threaded shank portion (17), a torque receiving portion (13) integrally connected on one end of the shank portion (17) and a radially extending flange (15) located between the shank portion (17) and the torque receiving portion (13). The flange (15) includes a pair of cut-out notches (9, 11, 12) located on the periphial edge of the flange which are formed prior to initial tightening of the fastener (1) and are spaced apart at a predetermined angular distance to allow a user to utilize the Torque Angle method to provide predictable clamp load across a joint connection. Primarily, the method has three basic steps, first each of a plurality of fasteners is tightened to an intermediate torque, a mark is placed on the surface of the element to be clamped adjacent the leading one of the notches on the fastener and finally the fastener is rotated until the second notch of the pair is brought into alignment with the surface mark.