Design&Research Of The Measurement And Control System For Rail Fine Grinding Machine

The continuously welded rail (CWR) technology for rail transport plays an important role in promoting high-speed passenger and freight overloaded railway construction. With the rapid development of high-speed railway, the quality of the CWR has become increasingly demanding and the rail ride comfort indicators have become more stringent.And the CWR is made up of one or several long welded rails. The ability of maintaining the geometry at the rail welding joints is relatively weak. The ride comfort of rail surface is directly related to the quality of the entire CWR.Therefore, grinding rail welding joints to maintain flatness is a key step in the whole CWR machining process. As the special grinding equipment, rail fine grinding machine is designed for grinding the rail welding joint. And its independent research and development is urgently needed.Considering the actual production of the CWR and the usage of fine grinding equipment for rail welded joints, the overall design of fine grinding machine for rail welded joints is put forward through combining with the CWR production and processing technology. Under the requirements of maintaining the contour shape of the rail head and the welded joints or rail surface being undamaged after grinding,to ensure a natural transition between grinding surface and non-grinding surface, the machine is needed to keep grinding device parallel with rail surface. Due to the welded rail is several hundred meters long and the grinding range contains only a few segments of welded joints, it is difficult to determine a uniform grinding reference. Therefore, the design and research of the measurement and control system for rail fine grinding machine is proposed.NI PCI-6023E multifunction data acquisition card (DAQ) is used as hardware control core in the measurement and control system for rail fine grinding machine. High-sensitivity vibration sensor and rotary encoder of servo-motor are used to determine uniform grinding reference. Laser ranging sensor is also applied to detect the rail surface flatness and to determine the grinding feed, thus reducing the grinding error by grinding head wear. The front panel of measurement and control system is designed by using LabVIEW software and virtual instrument technology. Then measurement and control program is written by using graphical programming language. Lastly, PCI-6023E multifunction data acquisition card is verified by using DAQmx simulated devices, and the control panel functions are tested through inputing analog signal. As an essential equipment for high-speed railway construction, the independent research and development of rail fine grinding machine concerns to the level of localization for railway equipment and its related significant economic value. Moreove, it also shows the positive significance with respect to enhancing core technology competitiveness of major equipment manufacturing industry.