Research On The Test Method Of Acoustic Emission Instruments And Accessories

As a mature non-destructive testing method,acoustic emission testing technology has been widely used in equipment testing and structural integrity evaluation,providing technical support for the safe operation of equipment.Acoustic emission instruments and accessories,as the carrier of acoustic emission detection,are an important basis for reliable detection data.Acoustic emission instruments are prone to problems such as decreased sensor sensitivity and signal cable interference and damage during use.However,the calibration of acoustic emission instruments and accessories requires a high cost and a long cycle,which is difficult to meet the actual needs of users.Starting from the direction of conformance testing of acoustic emission instruments and accessories,this paper studies and designs a set of conformance testing devices for acoustic emission instruments and accessories,and tests three sets of typical acoustic emission testing instruments respectively.The main work of this paper is as follows:(1)This paper introduces the principle of acoustic emission detection and the development of acoustic emission instruments,and analyzes the research content of acoustic emission calibration at home and abroad and the evaluation criteria of standards related to acoustic emission calibration.Based on the relevant research and standards of acoustic emission calibration,a conformance test device for acoustic emission instruments and equipment was designed and built,and two sets of typical acoustic emission instruments and accessories were tested for consistency.(2)Through experiments and simulations,the signal response characteristics of different sound sources and the influence of test block size on signal propagation are analyzed.The results show that the sound source generated by the pulsed signal excitation sensor has better stability and reproducibility,and the overall response amplitude of the pulsed excitation is 5-12.7 dB higher than that of the lead-break excitation.The acoustic signal starts to attenuate regularly with the increase of propagation distance in test blocks of different diameters and thicknesses,and after a certain distance,it is easy to fluctuate due to the influence of edge reflection.Among them,the circular test block with a diameter of D=600 mm and a thickness of d=8 mm has the most stable signal attenuation and the fluctuation of the response amplitude is the farthest away from the excitation source.(3)Three sets of typical acoustic emission instruments and accessories were tested for consistency,the parameter characteristics and deviation distribution of the received acoustic emission signals were analyzed,and the use status of the acoustic emission instruments and accessories was evaluated and graded through evaluation indicators.It provides a reference for adding a method for evaluating the consistency of acoustic emission instruments and accessories in the testing standard.