Vibration Detection System’s Development & Testing Research At High-speed Steam Turbine Manufacturing Stage

With the economic development and the increasingly serious situation of the energy industry,small size and high-speed high-efficiency steam turbine is more and more widely used in the energy and power industry.In order to ensure safe and stable operation of the STG set at project site,the main shaft as a key component of turbine must be doing factory vibration test before delivery which is the precondition.In this paper,based on the requirements and characteristics of vibration detection in manufacturing plant,for high-speed characteristics of the tested main shaft,the research is based on the non-contact type of eddy current sensor,which is suitable for the vibration detection technology inside the manufacturing plant and the criterion that can guarantee the shaft vibration detection in the later stage,based on LabVIEW software development,a set of digital high-speed turbine shaft vibration testing system to achieve high-precision measurement of small high-speed turbine shaft radial run-out before leaving the factory.In this paper,by analyzing the factors causing the shaft vibration and studying the influence of the shaft vibration amplitude in the factory on the field operation vibration of the steam turbine,the criteria for guaranteeing the smooth running of the shaft and the authenticity of vibration detection in the manufacturing plant are proposedBy studying the working principle and principle of the eddy current sensor,the mathematical model of the equivalent electromagnetic field is established,and the relationship between the measured physical parameters and the output characteristics of the eddy current sensor is deduced.The eddy current sensor is adopted to solve the non-contact measurement problem caused by the high-speed shaft.The whole test system is designed based on LabVIEW program software,the principle structure chart and data processing flow chart are established,the function program block diagram is established,and the main function is designed according to the function design of each module of the system,and the relevant detection system hardware facilities are selected.Through the verification of the internal testing of the manufacturer,the testing process and the test results are analyzed to verify the corresponding functions of the testing system developed.Through the turbine non-load test tracking to verify the detection system for the latter part of the vibration detection necessity and effectiveness.According to the test data accumulated during the promotion and use process,the authenticity and accuracy of the designed system are further confirmed,the problems arising in the course of use are analyzed and proved,and the solutions to the similar problems that may occur in the later stage are proposed.innovation point:1.The equivalent mathematical model of non-contact vibration detection of high-speed shaft journal with eddy current sensor is studied.The relationship between the variation of distance and the change of functional parameters of eddy current sensor is obtained,which lays the foundation for the non-contact shaft vibration detection2.Adopting the test program of increasing the number of circumferential sampling points,complementation of double monitoring points and the vacuum test chamber,the instability of the shaft speed and the disturbance of air flow on the detection data during high speed operation are reduced,and the requirements of high speed detection are met.3.Using LabVIEW software,a digital inspection and testing system was set up to collect and analyze the shaft vibration data.The data collection error was reduced during the operation.The data of the shaft was compared by the three-coordinate tester to ensure the accuracy of the verification.The correctness of the detection system...