Development Of Online Ultrasonic Flaw Detection System For Roll Grinding Machine

Roller is a crucial tool in steel rolling production whose performance will directly affect rolling mill output and product quality. Inefficient flaw detection will lead to spalling of online roller, causing its out of service prior to the life time. This will make a huge negative impact on production stability and cost reduction. With enhanced requirement over output and quality from companies, higher requirement of safe utilization of roller has been brought up. To avoid rolling accident caused by defect of roller, proper choice of roller nondestructive test (NDT) method and its correct practice are crucial.The research of this topic aims at designing the development of online ultrasonic flaw detection system for roller grinding machine and improving the ability to test defect inside rollers. The research of this article mainly includes the following aspects:Firstly, by consulting large amount of reference documents, the following work have been conducted:research the technique of roller NDT, analyze the advantages and disadvantages of roller NDT, analyze the testing principle of ultrasonic and ultrasonic flaw detection, study the cause of detect inside roller and judgment method of detect, analyze the development status of ultrasonic flaw detection, and expect the development trend of ultrasonic flaw detection.Secondly, on the basis of working mode of the ultrasonic flaw detection system of roller grinding machine, proposal for overall hardware of designed control system has been put forward, mainly including probe, signal treatment unit, industrial control computer, coordinate collecting unit and coupler filtering system.Thirdly, in terms of hardware design, probe will use single crystal normal probe with longitudinal wave from German K. K Company and ultrasonic signal treatment unit will consists of power module, transmitting circuit, amplitude limiting circuit, amplifying circuit, filter circuit, detection circuit, A/D conversion circuit, FPGA logical control circuit and designated PCI6220 interface circuit.Fourthly, in software design, Lab VIEW, software for development of ultrasonic flaw detection system for roller grinding machine, will be used. The software system mainly includes user login system, parameter configuration, data collecting program, ultrasonic testing program and history review program.Finaly, by testing of calibration roller and manual flaw detection, it is concluded that ultrasonic flaw detection system is able to detect the defect inside rollers. By expecting the technique of roller flaw detection in the end, this article put forward the compound flaw detection mode with multiple probes and functions, which will be the development direction of roller flaw detection technique.