Method for determining bolting torque

A bolting torque determination method comprising:

• a preparation process of preparing samples of an object and samples of a bolt which are to be respectively bolted;
• a sample fracture torque acquisition process of measuring and acquiring a sample fracture torque at which at least one of the samples of the object and the samples of the bolt is fractured when the samples of the object and the samples of the bolt are respectively bolted;
• an effective fastening torque zone determination process of determining an effective fastening torque zone, in which fastening of a sample object and a sample bolt is performed without fracture for the samples of the object and the samples of the bolt, on the basis of the sample fracture torque;
• an experimental torque selection process of selecting a plurality of experimental torques within the effective fastening torque zone;
• a bolt fastening angle measurement process of performing test fastening on the samples of the object and samples of the bolt according to each of the selected plurality of experimental torques and measuring bolt fastening angles;
• and
• a bolting torque determination process of determining a bolting torque, which is to be used for bolting of an object and a bolt to be bolted among the plurality of experimental torques, on the basis of the measured bolt fastening angles,
• wherein, in the bolt fastening angle measurement process, a rotation angle of each sample bolt is measured from a predetermined reference point of time to a point of time when the test fastening is finished, and
• wherein the reference point of time is a point of time when a force applied to the sample bolt during the test fastening is changed from a rotational force to a fastening force.