Development of auto-on-line calibration and adjustment system for power plant spring safety valve

An auto-on-line plant boiler spring safety valve calibration and adjustment system was developed to solve the problems of poor accuracy and low working efficiency existed in the traditional artificial calibration method. The working principle and system design scheme is introduced. A novel algorithm was presented to calculate safety valve adjustment coefficient on-line. In this algorithm, safety valve adjustment coefficient could be calculated according to two adjacent popping pressures and the safety valve adjustment value. The result of experiment and testing curve of sum pressure, steam pressure and hydraulic jar oil pressure is given through an applying example on 1700 spring safety valve. The experiment result shows that the new technique is more efficient and accurate than traditional artificial system. Using the new technique, calibrating and adjusting ten safety valves of one boiler only need 4 hours saved 9 hours than traditional method. After adjusting, the error of every popping pressure is less than ±1%.