1. Scope of the project: Take anti-burst measures at the end of the 8m west of the center line of the slippery coal to the end of the headroom. 2, anti-burst measures hole design 2 rows, drilling diameter φ75mm, spacing between 700 × 300mm (in the shed space), the first row of coal seam roof 1.3m, measure hole depth 8.5m (in the direction of tunneling projection), vertical Arranged in the coal wall and along the roof of the coal seam. At the end, dense fan-shaped holes are arranged at the end to relieve the blank belt. 3. The effective inspection hole starts from 7m west of the coal bunker center line, and an effective inspection hole is arranged every 3m; the end of the coal wall is arranged at the distance of 1m from the upper and lower sills, and the effective inspection hole diameter is φ42mm, 700mm away from the coal seam roof. The hole depth is 7.5m (in the direction of tunneling projection), perpendicular to the coal wall and along the roof of the coal seam. 4. The effective inspection index adopts the cutting dust gas desorption method with a critical value of 200Pa. When the desorption index is <200Pa, the coal and gas outburst danger is eliminated, and the coal bunker is allowed to be installed. When the desorption index is ≥200Pa, there is still coal and gas. In order to highlight the danger, it is necessary to take supplementary measures (replace a row of measure holes between the two rows of measure holes within 3m of the indicator over-limit hole) to re-test the test and pass the test. 5. If there is a phenomenon such as pinching or nozzle hole during the construction process, the discharge hole should be added between the holes around the measure hole to fully relieve the pressure of the coal body. SWRO& Water Treatment SWRO& Water Treatment ZHEJIANG BOTUOLINI MECHANICAL CO.,LTD , http://www.botuopump.com
In order to ensure construction safety, to take outburst prevention measures against coal roadway near Coal Chute, as follows: