抄録
The shape is not essentially symmetrical with the screw thread. The bending moment is caused in the bolt shank by the load distribution of screw thread which is not symmetrical in the tightening. It confirms that this bending moment is small by the analysis. However, the big bending moment in the bolt shank is caused by the inclination of the bearing surface at the tightening. The bending moment which influences relations between the torque on fitted portion of threads and torque on bearing surfaces is examined by the experiment.
