Abstract: An annular shaped-charge and blasting housing and a use method thereof are provided. The annular shaped-charge and blasting housing includes a PVC segment and multiple notch grooves. Grooves are notched on a W-shaped PVC segment formed by machining. The notching angle of the groove and the spacing distance between the grooves can be adjusted according to use requirements. And, the W-shaped PVC segment after being cut may not be limited to have eight notch grooves, and the number of the notch grooves of a single one PVC segment can be adjusted according to actual working conditions. The PVC segment can be folded and closed to form the annular shaped-charge and blasting housing. Therefore, the housing of the embodiments is simple in production, the linear segment can be bended and folded by utilizing the plasticity of the PVC material. The manufacturing process of the housing is simple and feasible.

Abstract: The present disclosure relates to the technical field of coal mining, and in particular, to a mining method without coal pillars with roof-cutting and roadway retaining, comprising: constructing a gas drainage roadway and eliminating outbursts in a working face transport gate area and a working face track gate area on opposite sides of a first mining working face; constructing the working face track gate, the working face transport gate, a first process roadway and a second process roadway, one end of the working face track gate is communicated with an air return roadway, the other end is communicated with the gas drainage roadway by the first process roadway, one end of the working face track gate is communicated with the air return roadway, the other end is communicated with the gas drainage roadway by the second process roadway; stoping the working face, forming an roadway retaining section, the roadway retaining section is communicated with the gas drainage roadway by the first process roadway and the sec

Abstract: The present disclosure relates to the technical field of mine ventilation, and in particular, to a three-dimensional ventilation method and system for mining by 110 construction method in coal and gas outburst mines.

Abstract: An annular shaped-charge and blasting housing and a use method thereof are provided. The annular shaped-charge and blasting housing includes a PVC segment and multiple notch grooves. Grooves are notched on a W-shaped PVC segment formed by machining. The notching angle of the groove and the spacing distance between the grooves can be adjusted according to use requirements. And, the W-shaped PVC segment after being cut may not be limited to have eight notch grooves, and the number of the notch grooves of a single one PVC segment can be adjusted according to actual working conditions. The PVC segment can be folded and closed to form the annular shaped-charge and blasting housing. Therefore, the housing of the embodiments is simple in production, the linear segment can be bended and folded by utilizing the plasticity of the PVC material. The manufacturing process of the housing is simple and feasible.