Abstract
Recent research into the tightening at the yielding point has brought to light the characteristics of this method and shown that it is both practical and effective. In this report, the tightening at the yielding point was carried out on screw of M10 by systematically changed snug torque to find out what effect the snug torque setting has on the tightening at the yielding point of screw. The main results of these tests are shown below. (1)When carrying out the tightening at the yielding point using the torque gradient control method, it is necessary to the select a suitable snug torque. In these experiments a range of 10〜60% was used. (2)Stable tightening is possible within a snug torque range in which a stop point can be clearly detected. (3)The torque coefficient in the tightening at the yielding point is slightly lower and more stable than in elastic region tightening.
