Research On Application Of Ultrasonic Nondestructive Testing In Bolt Flaw Detection

In recent years,the total installed capacity of wind turbines in my country has increased year by year,and the safe and effective operation of wind turbines has also received more and more attention from relevant departments.Bolts are the main connection structure between the components of wind turbines,and the effectiveness of bolt connection is also the effectiveness of wind power generation.The fundamental guarantee for the safe operation of the machine.Therefore,this subject develops a more accurate and complete ultrasonic non-destructive bolt detection system based on the traditional bolt condition detection.The main research contents are as follows:Firstly,the advantages and disadvantages and application conditions of commonly used non-destructive testing methods are analyzed,the development status of ultrasonic testing technology at home and abroad are investigated,and the shortcomings of ultrasonic non-destructive testing in the application of bolt flaw detection is analyzed.Common defect types determine the overall research plan of this article.Then the basic principles of the DDS signal generator are analyzed,a dual-channel DDS signal generator is designed that can output control pulses and gain control outputs based on FPGA;the basic types of ultrasonic probe excitation pulses is analyzed,design three types of pulse excitation circuit modules,and pass specific The experiment compares and analyzes the incentive effects of the three incentive methods,and selects the best incentive method suitable for this system.Then the basic principle of wavelet threshold denoising is analyzed,echo signal noise processing algorithm is designed;This paper analyze the basic principle of energy method,improve the energy method based on the basic characteristics of bolt internal defects,greatly improve the accuracy of internal defect recognition;study the cross-correlation algorithm the basic principle of the design of the cross-correlation bolt looseness recognition algorithm verifies the effectiveness of the cross-correlation in bolt looseness recognition.Finally,the hardware circuit function test is completed by building an experimental platform,and the test data is verified by the damage recognition algorithm.The results show that the bolt flaw detection system can accurately locate the internal defects of the bolt and identify whether the bolt is loose.