Seam high-pressure injection pumps BZW31 5/25 BZW40/20 BZW50/16 BZW63/12, 5 BZW80/10 BZW100 / 8 3BZ-135/17 BZW40/50 BZW80/25 BZW100/20 BZW125/16 BZW63/31, 5 BZW200 / 31,5 BZW160/12 5 BZW50/40 high pressure water injection: Coal Seam Water before excavation work on the coal seam water injection pressure. The waterflood is generally to dig good recovery roadway or near the roadway. The purpose is to change the physical and mechanical properties of coal by physical and chemical effects of the pressure of the water, the lower seam burst tendency. Implementation of the the coal high pressure water injection pressure relief, starting from the change of the physical and mechanical properties of the coal, coal, high-pressure water injection to achieve the purpose of relief. Pressure water into the coal along the weak surface flow, play a role of fracturing and erosion, and water on the wedge effect of the crack tip (water wedge effect), so the reason fractured coal expanded to produce a new fissure, destruction the integrity of the coal, reducing the intensity. It can not only eliminate or threat to cushion the impact of pressure, also played eliminate dust, cooling, improve labor conditions. The seam pressure water injection, hydraulic fracturing and long moist role of coal properties change, tendency to reduce the impact, but also played eliminate dust, cooling, and improve labor conditions. Seam thicker than the hard coal hard or seam roof by drilling injection pressure water to the coal seam or roof so hard seam or roof to change their physical and mechanical properties, may be breaking down the seam or roof. Pressure water on the coal seam or roof fracturing and softening the role of the two the fracturing effects include the increase in coal and rock fissures, expansion cracks, bedding separation and reduce the gap between bond strength. Cracks in the coal seam by drilling high pressure water injection increased to make moist coal mining to reduce coal dust amount.