Design And Research Of A Rapid Remanufacturing Parts Defects Recognition System In Engineering Machinery

In the engineering machinery manufacturing field, research and application of remanufacturing is very important in developing circular economy, improving economic efficiency of enterprises and conserving resources. While, whether we can achieve rapid detection of defects remanufactured parts, is one of the key technologies in the remanufacturing.In order to achieve a rapid recognition of the old pieces in engineering machinery remanufacturing process, a remanufactured parts rapid recognition system is created based on the ultrasonic flaw detection method. The hardware of the system comprises a probe servo control module and data acquisition module. Probe servo control module is used for automatic controlling the probe trajectory according to set procedures, data acquisition module withing a ZXUS-PC41 type ultrasonic data acquisition card can collect data in high speed. A control program is used to set the running parameters and for data processing.Ultrasonic signal transmitter/receiver is completed by I/O function, which is provided by ZXUS-PC41 data acquisition card software development kit, in the control program development process. Multithreaded programming techniques is used to achieve multi-channel echo signals displayed simultaneously when analytical processing of echo data. Data compression technique is used to treat the problem of waveform distortion in multipoint sampling, automatic gain adjustment method to automatically adjust the gain. An alerting threshold is setted to send alarm message automatically when the defect is detected, and triggers defect recognition processing program. Acoustic distance is determined by the relation between the echo time and the speed of sound, and the defect position is determined by the geometric relations of acoustic path. Defect sizing technique which is based on ultrasonic sound beam directionality is used to identify the defect geometry size.When dealing with the probe trajectory planning problem, the parts under test is divided into planar structure, surface structure and welding seam structure according to the surface feature detection. To proceed designing plan of the probe point arrangement and movement respectively. And then, for various different probe types and size of defects, do analysis to its location and size of defects, obtainning the general method to identify defective features derived.Finally, the cylinder old parts defects detect test is completed by using single straight probe testing method, single probe tip oblique angle echo testing method and double angle probe testing method. And the butt weld defect of the steel plate is detected by using monoclinic probe and double oblique probe testing method. The test results is in line with expectations.