| 摘要 |
PROBLEM TO BE SOLVED: To measure axial force by coupling by a screw or a bolt in excellent work efficiency.SOLUTION: A block BL having a top face and a bottom face which are mutually parallel and side faces is inserted between a screw or a bolt S and the surface of an object M which is a coupling target. An X-ray is irradiated from a diffraction ring formation device having an X-ray emitter 10 and an imaging plate 15 onto the side face of the block BL, to thereby form a diffraction ring on the imaging plate 15, and residual stress of the block BL is calculated by detecting the shape of the formed diffraction ring. The axial force by coupling by the screw or the bolt S is determined from the obtained residual stress by calculating a relation between the residual stress and the axial force, which is obtained beforehand. |
