| 摘要 |
<p>A screw fastener testing method for verifying the status of a previously tightened screw fastener with respect to installed torque and actual torque growth per angle of rotation properties includes applying an increasing tightening torque on the fastener, measuring the torque magnitude at the start of rotation, of the fastener, measuring the rotational movement of the fastener after the start of rotation, calculating the torque growth per angle of rotation for a certain predetermined test interval of rotation from the start of rotation, comparing the torque magnitude indicated during rotation and the calculated torque growth per angle of rotation during the test interval of rotation with predetermined reference values (Tstart, KR) or (TE, KP), respectively, characteristic for the actual fastener when tightened to a desired target torque level, and approving or disapproving the fastener status in view of the reference values.</p> |
