Testing And Analysis On Pre-Tightening Force Signals In The Process Of Turbopump Shafting Assembling

The turbopump which is the only high-speed component in engine requires higher assembly quality. This paper mainly studies the turbopump shafting assembly process in order to avoid the vibration in engine testing.Based on the analyses of screwing methods and the technology of measuring axial force, the actual force is analyzed in the process of screwing by torque, the finite element analysis model is established,and the key components is analyzed,then the results is compared with the driving frequency.In order to study the effective pre-tightening force and its influencing factors, the experimental platform which is composed with torque wrench and pre-tightening device is established. Two sets of detection system is developed. One is composed with sensor, transmitter, A/D data acquisition card and computer, the other is composed with sensor, transmitter, A/D chip, SCM, nixie tube.The main factors which influence the effective pre-tightening force have been studied, including thread quality, plastic deformation, sleeve circumferential position and so on. Finally, the natural frequency of turbopump shafting got from the spectrum analyzer has been compared with the result of finite element analysis. The experimental results show that the experimental platform loading range is 0-100N·m, the pre-tightening force measuring range is 0-30000 N, the detection system precision arrived 0.008%, so this platform can be satisfied the requirements and practical testing results is reasonable.