Research on intelligent conveying technology of 500 m ultra-long face scraper

In the field of medium and thick coal seam mining, intelligent mining of ultra-long face is the development trend of coal mining technology, and intelligent transportation is an important part of it.Based on the summary of the problems of the scraper transportation system in the intelligent mining of 400−450 m working face in China at present, the method of reasonable matching between the installed power and the volume of the intelligent scraper transportation system of 500 m ultra-long working face is explored, and the feasible scheme to solve the technical problems of scraper transportation of 500 m ultra-long working face is proposed.Based on the technical scheme of selection of three fully mechanized mining machines and the application practice of high-end transmission system above 2 000 kW, the domestic 2 500 kW high-power variable frequency integrated intelligent transmission system is developed, including variable frequency integrated motor, reducer, moment limiter, etc. The key technologies and key components are realized in China.In order to solve the technical problem that the center of gravity of the transmission device is shifted back and the middle groove width parameter is unchanged, which is not conducive to the smooth moving of the end equipment, the anti-deflection technology of the high-power transmission device configured with medium groove width is studied, the multi-working condition moving model of the head (tail) moving part is established, and the structure of the moving part is optimized. The problems of overall head imbalance, serious drift and aggravating difficulty of moving are solved due to the deflection of transmission device.In view of the problems that the hydraulic motor is difficult to drive when the coal load in the middle trough is large after the scraper chain is broken, the digital hydraulic motor with large torque is selected and the digital motor control system is developed to reduce the working intensity of the scraper chain maintenance.Based on the demand for real-time deformation compensation of chain during the safe operation of scraper transportation equipment, the tensioning control strategy of 500 m haul chain is proposed, and the intelligent adjustment technology of chain tension with load gradient during operation is developed to solve the dynamic compensation problem of elastic deformation of 500 m haul chain. Moreover, AI high-definition camera is installed on the upper end of the tail frame cover plate to realize real-time detection of the running state of the chain, which provides convenience for the staff to real-time control of the running state of the chain.In addition, in order to improve the adaptability of the telescopic tail to a variety of complex working conditions and ensure that it can expand freely during the service cycle, a technical scheme is proposed to improve the strength and stiffness of the telescopic tail from three aspects of structure, material and manufacturing process, and the hydraulic cylinder protective cover and automatic flushing system of the telescopic tail slide are developed to further improve the reliability of the telescopic tail.Underground field industrial tests show that: The equipment capacity and installed power matching reasonable, 2500 kW frequency conversion integrated intelligent transmission system occupies less space, accurate torque transmission, inclined push head (tail) push part is stable and reliable, digital hydraulic motor to deal with the problem of broken chain convenient and labor saving, the retractable tail according to the load gradient automatic tensioning without stuck, to ensure the safety and efficient transportation of coal. It provides technical support for intelligent mining of 500 m ultra-long working face.