The Develop Of Ultrasonic Feature Scan Im Aging System Of Bar-shaped Workpiece

The development of automatic testing system of bar workpiece has become verysophisticated, due to the geometry of the special frame member and manufacturingprocess is very precision, the existing detection methods is difficult to meetthe automatic detection for some rod special workpiece.This paper developed a set of imaging system of Ultrasonic Feature Scan (F Scan)for automatic internal defects of rod-shaped workpiece, which detect theconventional structure bar workpiece automatically, the system meet the testingrequirements for a variety of special structure of the rod-shaped workpiece by theuse of specific jig, the parameter setting.The system acquise the signal by full wave through the influence of defects totime domain and frequency domain to ultrasonic, change the time domain andfrequency domain, extract data, analysis and imaging from defects in materialcharacteristics and the characteristics of ultrasonic signal itself. And improve theultrasound characteristics scanning imaging system precision, anti-interference,applicable test work pieces and its scope to develop a feature imaging system thatequipped with automatic test that directs at the internal flaws of the bar material. Inthis way, the efficiency of quality inspection for the work pieces of the bar materialcan be elevated, the leak test and false test rate of the flaws can be decreased, and theresult can be clear, reliable and practical.The works of the paper are as follows:A mechanic and auto scan system of high precision is designed and developedwith programmable logic controller (PLC) being the master control and servo motorbeing the dynamic core. The double driving shaft which rotates the bar material incoordination with anti-interference synchronous circuit board and safety protectiondevice provides a stable and reliable mechanic platform for scanning imaging. Theminimum step is0.1mm.A delaminating software system is established through the after treatment onultrasonic signal of the whole wave train and the frequency domain. Flaws arerecognized accurately according to the corresponding disposes on model selection ofthe detector, the material of the work piece and the characteristics of the flaw. Theresult is reliable and direct by means of the size, shape and depth position of the image.The stability of the system operation is elevated by conducting noise proof on thesystem as a whole; at the same time, the resolution of signal asynchrony whichfrequently occurs in automatic control system by the design of signal synchronouscircuit is conducive to the clarity of the imaging and the precision of the test result.The system can test the bar material automatically and eradicate false estimationand test failure of the scan. It can meet the needs of the scan for bar material rangesfrom Φ20to Φ80m×1000mm and save the results in image form.The established system is used to evaluate the reliability of the test method, thestability of the system as a whole and repeatability of test which aims at the automatictest and imaging for bar material of a specific standard.