| Titanium and its alloy materials have been widely used in nuclear power construction,because of their high temperature resistance,high strength and corrosion resistance.Although our country has many years of titanium and titanium alloy tube production experience,but for the high precision thin-walled titanium alloy pipe processing technology is still relatively backward,especially for the tube wall thickness uniform control.At present,titanium alloy seamless tube are mainly manufactured by cold-rolled,and most of the tubes have uneven wall thickness after rolling,what we need to do is accurately to obtain the distribution of the tube wall thickness and the subsequent modification of the tube wall thickness.This paper aimed at the measurement of titanium alloy tube and grinding process,to obtain the tube wall thickness distribution using ultrasonic detection technology,combined with the technology of the abrasive belt grinding for the tube wall thickness with grinding,in order to achieve the correction of uneven wall thickness.The main research of this paper is as follows:(1)Several methods and principles of measuring wall thickness are discussed and analyzed and according to the actual demands,the thickness measurement method of ultrasonic pulse reflection is selected.Water was selected by comparing as the coupling agent for ultrasonic measurement,the coupling mode of in the immersion method is selected after comparing several kinds of coupling methods.According to the necessary condition of the accuracy of ultrasonic inspection,the clamping and adjusting device of the probe is designed reasonably.(2)Theoretical analysis of water layer thickness between probe and tube in ultrasonic thickness measurement is carried out,to discuss the optimum location of probe focus,and on this basis,different probes are used to detect tubes with different thicknesses,get the best thickness of different types of probes for the detection range.According to the distribution of tube wall thickness,the theory,algorithm and program generation method of reasonable data acquisition and processing are given,and designed the running path of ultrasonic inspection.Calibration the velocity of the titanium alloy material,and by which to verifying the ultrasonic measurement accuracy and stability through the experimental.The key factors affecting the ultrasonic thickness measurement system error through theoretical analysis and experimental verification,and puts forward specific solutions(3)The theoretical analysis is carried out of the force in the process of tube grinding,and to develop the force measuring mechanism to measure the force in the actual grinding of the tube.By comparing with the theory,to determine the linear relationship between different grinding parameters,different types of tube and its force size.Through the simulation analysis and experimental verification of thin-walled titanium alloy tube,to provide the guidance for the selection of grinding parameters.(4)Analysis the grindability of titanium alloy,and according to this to compared and verified the wall thickness and abrasive belt grinding schemes of titanium alloy tubes by experiments,then determine the best grinding scheme.The influence of different grinding parameters on grinding effect is verified by experiments,under the premise of grinding parameters and grinding scheme,to selected the suitable abrasive belt and confirmed its the service life by comparing experiments.Through the study of the ultrasonic testing of tube before and after grinding,to determine whether its reach uniform wall thickness requirements by the abrasive belt grinding,to verify the practicability of this system. |
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