I. Safety Risk Analysis (I) Safety risk of personal injury caused by material splashing. (2) Safety risk of not wearing goggles. (3) Safety risks of pipeline blockage and pipeline burst. (4) Failure to deal with the safety risk of pressure relief. (5) The safety risk of shotcrete machine handling and hoisting. II. General Provisions (1) Before construction, the supporting workers must seriously study and master the supporting forms and technical parameters specified in the operation procedures. In the process of construction, careful operation must be carried out in accordance with the requirements of supporting instructions and quality standards to ensure safe construction. (2) The thickness, strength and other parameters of sprayed concrete must meet the design requirements. (3) The following supporting materials shall not be used in the construction: 1. Proof materials that do not meet the requirements of operating procedures. 2. Supporting materials, structural forms and quality requirements should comply with the operating procedures. 3. Spraying of expired and invalid accelerator, cement and anchoring powder. 3. Preparation before startup (1) First drain the oil and water in the oil-water separator (2) Check whether there are sundries in the hopper, and check whether there are any faults in the water ring, signal system, electrical wiring grounding device and pneumatic conveying pipeline. (3) Check whether the rubber binding plate and the rotator are rusted and glued. (4) inching test run, check whether the rotating body rotates in the direction of arrow. (5) Open the air inlet valve, preset the pressure to be started according to the length of the conveying pipe, blow the pipe with a compressed air pipe for 2 ~ 3 minutes, start the motor to confirm that everything is normal, and then feed and start the car. (6) Before construction, prepare supporting materials and construction tools. (seven) before and during the construction, often knock to help ask the top, with long-handled tools to deal with dangerous stones and living stones in time. (8) Before spraying, the specifications and quality of roadway section should be checked according to the waist line, and the unqualified parts should be handled well. (9) Before construction, cover the pipeline facilities such as wind, water and electricity. Construction equipment should be placed in designated places. Four. Precautions during operation (1) Feed into the hopper evenly and continuously. (2) Pay attention to the change of total wind pressure and working pressure gauge value. When the delivery pipe is blocked, the working pressure rises rapidly, which is close to the wind source pressure. At this time, feeding should be stopped immediately, and power, water and wind should be stopped for processing. (3) The driver should stick to his post, pay attention to the machine operation and contact signals, monitor the feeding situation and ensure the normal operation. If there is any fault, immediately cut off the power supply and wind source, and stop feeding for treatment. (4) The ingredients shall be made in strict accordance with the mixture ratio in the operating procedures, and the water content shall be 8 ~ 10%. (5) Conveying materials: When the mixture is ejected from the conveying pipe, it should be observed whether the working pressure is appropriate. Too much rebound means that the work pressure is high. If the adhesion of spraying layer is insufficient, it means that the working pressure is low, and the working pressure should be adjusted in time according to the signal of spraying site. (VI) Stop and start sequence of the machine: When starting the machine, the gas should be supplied first, then the motor should be started, and then the material should be fed. When stopping, stop the material first, then cut off the power, and then stop the wind. Reverse operation is absolutely not allowed, so as to avoid damaging parts and causing accidents such as material blockage. 4. Spraying concrete (mortar) shall comply with the following provisions: (1) The following preparations must be made before spraying: 1. Check whether the anchor installation and metal mesh laying meet the design requirements, and handle the problems in time when found. 2. Clean up the waste rock (coal) and other materials at the injection site and connect the feng shui pipe. The pipeline should be straight without sharp bends, and the joints must be tight without air leakage. It is forbidden to use non-conductive plastic pipes as conveying pipes. 3. Check whether the shotcrete machine is in good condition, send it to no-load test run, tighten the friction plate, and no air leakage is allowed. 4. Before spraying, the rock surface must be washed with high-pressure feng shui. 5. In the roadway vault and two sides should be installed spray thickness signs. 6. Spraying personnel should wear complete and effective labor protection articles. (2) Requirements for mixing concrete: 1. The label, specification and material of materials used for shotcrete shall comply with the provisions of operation procedures and measures. Sand and gravel must be sieved before batching. 2. The ingredients must be measured according to the design mixture ratio. 3. When mixing materials manually or mechanically, wet mixing materials should be adopted. When mixing materials manually, cement, sand and stone should be cleaned and turned over for three times to make them mix evenly. The mechanical stirring time should be more than 2 minutes. 4. Must be in accordance with the provisions of the operating procedures of the mixing amount, evenly add accelerator at the inlet of the jet. (3) The operation of the jet shall comply with the following provisions: 1. The operation shall be carried out in strict accordance with the product manual of jet. 2. When starting the machine, you must supply water first, then turn on the gas, then start the machine, and finally feed the water. When stopping the machine, stop the material first, then stop the machine, then turn off the water and finally stop the gas. 3. In case of sudden blockage during injection, stop the machine immediately, then turn off the water and finally stop the wind. In the process of injection, when the pressure gauge pointer of the injector suddenly rises or falls or swings abnormally, it should be stopped immediately for inspection. (4) Technical requirements for sprayed concrete: 1. Reasonably divide the operation section, and the maximum width of the section shall not exceed 2m. 2. The spraying sequence is: wall first and then arch, starting from the wall foundation and proceeding from bottom to top. 3. The spray gun head should be as vertical as possible to the spraying surface. 4. The nozzle should follow the spiral trajectory of one and a half turns. The diameter of the spiral ring shall not exceed 250 mm. In the process of spraying, the water supply should be adjusted in time according to the change of output to ensure the accuracy of water-cement ratio. The sprayed wet concrete should have no dry spots, no flowing, strong adhesion and less rebound. 6. The thickness of sprayed concrete at one time should be greater than 50 mm ... If the thickness of sprayed concrete at one time can't meet the design requirements, it should be sprayed several times, but the interval of secondary spraying should not exceed 2 hours, otherwise the sprayed surface should be washed with high-pressure feng shui again. 7. After the spraying work starts, it is forbidden to aim the spraying spear at the personnel. When using vibration method to deal with pipe blockage, the injector should hold the nozzle tightly so that the nozzle faces down. 8. When spraying concrete in the surrounding rock seepage and water gushing areas, measures should be taken to reduce the water supply, increase the content of accelerator, and insert water guide pipes. 9. After spraying, the spraying layer must be watered continuously for more than 7 days, not less than once a day. 10. After an injection, clean up and collect the rebound immediately, and use the mixture on duty. V. Maintenance (1) After use, use compressed air to blow off the residual materials in the rotating body cavity and the conveying pipe, and clean the dust outside the body. (2) Remove the discharge elbow and remove the adhesive between the rubber adhesive plate and the rotating body. (3) Dismantle the seat body and remove the residual dust accumulated in the seat body. Six, in violation of operating procedures may cause poor roadway forming affect the engineering quality, poor supporting effect caused by roof accidents, etc.
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