Online measurement of bolt tightening force based on ultrasonic dual-wave method

To ensure the stability of the bolt connection, a certain tightening force is required on the bolt. Currently, the measurement of the tightening force of in-service bolts remains a technical challenge. This paper proposed a method to measure bolt tightening force using the ratio of ultrasound transverse and longitudinal waves, and verified through measurement, with the results showing high detection accuracy for the double-wave method.Studied the factors affecting the accuracy of the double-wave method, a temperature correction coefficient was proposed to compensate for the influence of temperature on the measurement of bolt tightening force. This method has high engineering application value in measuring the tightening force of in-service bolts.