The Research Of Weld Ultrasonic Testing Technology For The Region Of Frame VIN Code

The VIN code is called“ID card of the car”,it is made up of Arabic Numbers andletters,17in total.Through the numbers’ permutation and combination, the duplicatephenomenon is not happened in the same model cars in30years. The VIN code has the onlyidentification of vehicles. Recently the cases of criminals forging the VIN code emerge inendlessly.They often dig out the original region of VIN code,weld a piece of thecorresponding size steel plate,and forge matrix through such means as puttying and spraypaint.Then conduct a new frame number.It can achieve the result of real ones look from theexterior,it is difficult to identify through the naked eye and touch.The existing technology to test the region of VIN code of the public securityorganizations detecting such cases is not rapid and accurate.Confirm the ultrasonic testingmethod according to the principle of ultrasonic nondestructive testing,and A set of ultrasonicdetection system is adopted to test the region of VIN code in the article.The ultrasonic detection method of the region of VIN code is put forward in the paper,theoverall design scheme of the ultrasonic testing system is given.Realizing the transmitting、receiving and acquisition of the ultrasonic signal. LaBVIEW detecting interface is developed,it can set up the system parameter, display the waveform and judge the weld, etc.Comparingthe characteristics、differences of the echo signal with weld and the echo signal with noweld.The echo signal is analyzed using the method of the spectrum analysis.Weldidentification algorithm is designed.After detecting the different frames many times, thedetection accuracy of the ultrasonic testing system for frame weld is proved.