基于超声波的水轮机顶盖螺栓应力监测技术研究

Study on Technological Selection of Ultrasonic Based Stress Monitoring for Top Cover Bolts of Hydraulic Turbines

螺栓连接作为水电机组重要连接方式,其稳定性关系到整个机组的安全运行。机组运行环境因素会导致螺栓出现松动、断裂等,因此需对螺栓实时状态进行监测。分析了螺栓常用的应力监测方法,并对不同方法优缺点进行对比。针对水轮机顶盖螺栓特点选用超声波监测方法,并以M24标准螺栓试件进行了实验,验证了方案的可行性。

As an important connection method for hydroelectric units,the stability of bolted connections impact greatly on safe operation of the entire unit.Environmental conditions during unit operation can cause loose or break of the bolts,making real-time monitoring of bolt status necessary.This paper analyzes the commonly used stress monitoring methods for bolts and compares the advantages and disadvantages of different methods.Based on the characteristics of the top cover bolts of hydraulic turbines,ultrasonic monitoring methods were selected,and an experimental test was carried out on M24 standard bolt specimens which verified the feasibility of the technological scheme.