First, the type of roof, support methods 1, top type Seam coal layer 3 and 4 may be partially recoverable I miners mining, generally no false roof seam 5, which mostly directly shale roof (carbonaceous shale), siltstone or fine sand, a more complete hard; generally in the roof , coarse sandstone, complete and hard. The roof of my mine is easy to fall off ~ medium falling roof. 2, support method I ore mining, tunnel digging support ways: Coal Lane, semi-coal Lane is generally used to set up U-shaped steel arch support and other metal bracket supporting the anchor net (rope); rock roadway generally use the anchor net Shotcreting or Anchor spray support. The coal mining face must be timely supported in accordance with the provisions of the operating procedures, and empty top operations are strictly prohibited. The mining face of our mine generally adopts a single hydraulic prop with a hinged top beam to manage the roof. Second, the omen of common roof accidents 1. Sounds: The roof subsides, the mine pressure increases sharply, and the mining face supports deformation, fracture, and bending, accompanied by sounds. Before the old roof is pressed, the roof crack will also emit firecrackers or thunder. 2. Drossing: When the top plate is severely broken, the top plate appears to be slag 3. Piece of help: The pressure on the coal wall is increased, and the coal wall piece is more serious than usual. 4. Crack: mainly refers to the mining fissure caused by the sinking of the roof. The crack expansion shows that the roof is affected by the mining. 5. Separation layer: The method of tapping the top is used. For example, the top plate emits a “beep†sound to indicate that the upper and lower layers have been separated from the layer, which is a sign of the topping. 6. Leaky top: Broken false top or direct top, sometimes leaking tops before large area roofing. 7. The amount of gas emission increases. 8. There is water. Third, the prevention measures for roof accidents 1. Fully grasp the pressure distribution of the roof and the law of pressure. 2. Take effective support measures. 3. Deal with local leaking roof in time. 4, adhere to the help of the top system. 5. Targeted safety measures should be taken under special conditions. 6. Firmly oppose the idea that "quality is the root of life". 7. Operate strictly according to the operating procedures. 4. Emergency treatment measures and safety precautions after roof accidents 1. Emergency measures after the roof collapse occurs at the coal mining face 1) Rapid evacuation. 2) Avoid in time. 3) Call for help immediately. 4) Cooperate with rescue. 2. Emergency measures for the person who is blocked by the top of the road 1) Face the situation and calmly cope. 2) Do everything possible and seek relief. 3) Maintain the living conditions of the trapped location. 3. Method for rescuing people in distress after a roof accident occurs at the coal mining face 1) Suspend power supply to electromechanical equipment near the landing zone. 2) Check and maintain the safety of the landing site and its vicinity (whether the support is firm? Is there any gas escaping? Is there any danger of falling again?) to ensure the safety of the rescue personnel during the disaster relief, and there is smooth, Safe retreat. 3) When the range of the fall is not large, if the person in distress is pressed by the large piece of meteorite, the large rock can be supported by tools such as hydraulic jacks, and the person in distress can be rescued. 4) If the top plate falls along the coal wall, the rock mass is relatively broken. When the person in distress is close to the coal wall position, a small hole can be made from the outer roof to the inner wall along the coal wall. (If the person in distress is close to the topping area, then The trapping shed is set up from the outside to the inside of the cave. (The gangs of the landscaping area must be backed with wooden boards to prevent leakage of ochre). The side walls are supported and the rescued personnel are rescued. 5) The working face of the stratified mining has a roof, and the bottom is a coal seam. When the position of the person in distress is under the metal net or the false roof, the small hole can be smashed along the bottom coal seam, and the side hole is supported, close to the person in distress and then Rescue. 6) If the bottom plate is rock, when the position of the insurer is below the metal net or the false roof, you can approach the distressed person along the small hole in the coal wall, and then take measures according to the situation (such as using a wind to smash a small hole in the bottom plate) Etc.) Arrive at the person in distress and rescue him. 7) If the working face and the lower exit fall at the same time, or the middle of the working face has a large range of falling, and the person is blocked in the middle, when the small hole is long and unsafe, the method of re-opening the eye along the coal seam can be used. And save people. 4. Rescue method for the blocked personnel after a large area of ​​roofing occurred in the heading face 1) Suspend the power supply of electromechanical equipment near the roof area. 2) Use fresh air, water and food to the location of the person to be separated by means of air ducts, water pipes and drilling. 3) According to the location of the person in danger of being blocked, it is determined to use the method of restoring the fallen roadway or bypassing to reach the disaster-stricken place for the rescue. 1.R8 Shank Er Collet End Mill Chuck are made of high quality steel material, with hardness of HRC48-55. 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Hidden accidents in roof accidents and emergency treatment measures
Hidden accidents in roof accidents and emergency treatment measures