Analysis of the driving and passing performance of bolter miner under different geological conditions

The driving performance of the bolter miner is an important factor affecting its geological adaptability.In order to study the passage performance of the bolter miner under different geological conditions, the Sandvik MB670 bolter miner is used as the research object, and the 5^-2 coal seam of a domestic coal mine is used as the research background.Using track dynamic theory and multi-body system dynamics simulation method, the driving dynamic model of the bolter miner under different terrain conditions in the roadway is built, and the motion characteristics and stability of the bolter miner are simulated.The results show that the longitudinal topography is the main factor affecting the vibration of the fuselage.The greater the slope, the more serious the bolter miner slip phenomenon.When the longitudinal slope of the 5^-2 coal seam floor is 17%,the average slip rate of the bolter miner reaches 0.214.The bottom plate tilt is the main reason for the rapid increase in the yaw angle and offset of the bolter miner.The yaw angle and offset of the bolter miner on the concave bottom plate are very small, and the yaw angle on the convex floor is approximately constant while the offset increases linearly with the displacement.Through the DEM-MBD coupling simulation method, the dynamic characteristics of the machine on the four floors of full coal seam, water-bearing coal seam, 30 mm gangue coal seam and 60 mm gangue coal seam are studied.The results show that when the 30 mm gangue layer remains on the surface of the coal seam, the climbing angle of the bolter miner can reach about 19.5°,while when the thickness of the gangue layer is 60 mm, the climbing angle is reduced to 17°.When the coal seam contains water, the maximum climbing angle of the bolter miner is slightly lower than 19° in the whole coal seam.Although the average grounding pressure of the bolter miner is similar under different geological conditions, and the error is about 5% from the theoretical value, the grounding specific pressure of the bolter miner is the most unevenly distributed on the coal seam containing 60 mm gangue.The pressure difference of the track at different positions reaches 8 N/cm²,which is higher than the other three types of bottom plates.The thickness increase of the gangue layer will also causes floor sinking and accumulation problems.While a small amount of gangue layer improves driving performance, it also leads to an increase in the offset of the bolter miner and the acceleration during the start-up phase.Therefore, the gangue content on the floor surface should be controlled for different working conditions.