Transparent mining mode and key technologies of fully mechanized working face

In order to solve the problem that the intelligent mining technology based on adaptive working face geological conditions can not meet the practical engineering application requirements, a transparent mining mode of fully mechanized working face is proposed, which includes three stages, namely model construction, positioning of space to be mined and cutting control decision and execution. The mode is based on the coal seam occurrence exploration, and the 3D digital model of working face is taken as the object. The height adjustment control strategy of the shearer is formulated by cutting the 3D digital model and extracting the track coordinates of the roof and floor of the coal seam to be mined. Finally, the shearer adjusts the height control according to the cutting track parameters to achieve the goal of autonomous coal cutting. This paper expounds the key technologies of transparent mining in fully mechanized working face, such as establishment of 3D digital model, establishment of 3D laser point cloud model, model cutting and cutting planning and shearer height adjustment control. In the 43102 fully mechanized working face of Yujialiang Coal Mine of CHN Energy Shendong Coal Group Co., Ltd., the transparent mining mode and key technologies engineering application are carried out. The initial 3D geological model of the working face is constructed, and the borehole survey is completed along the boundary line between the roof and floor of the coal seam so as to realize the detection of the occurrence of the coal seam in the working face. After the acquired data is imported into the initial 3D geological model, a 3D digital model of the working face is obtained. Geological mapping is carried out daily during the mining process of the working face, and the error correction of the 3D digital model is realized through the mapping data. The real-time 3D laser point cloud model of the stope is constructed, the 3D coordinate data set at the junction of coal wall and roof in the 3D laser point cloud model is extracted to form a cutting line. The cutting line is used to cut the 3D digital model to obtain the contour curve of roof and floor in the next coal cutting cycle. By analyzing the changes of coal seam occurrence, the cutting plan is formulated to guide the automatic height adjustment control of the drum in the subsequent coal cutting cycle of the shearer. The application results show that the error of the 3D digital model is less than ±0.2 m, and the shearer can automatically cut coal according to the coal seam occurrence conditions of the working face.