Design and construction safety technical measures

The explosive material warehouse in the auxiliary shaft of KANGLONG coal mine is located 73.976m behind the +700 centralized transportation crosscut C # point, the design azimuth of the chamber is 23000 ′ 00 ″, and the total length of the roadway is 259.45m. The roadway is mainly used for the storage and distribution of underground explosives

according to the existing data, it is expected that the roadway will pass through A4 coal seam, and the adjacent coal seam is A3 coal seam. In order to prevent accidental faults and changes in the direction of the coal seam, A3 coal seam will also be drilled this time. Based on the fact that the +700 transportation crosscut has been constructed through the A4 coal seam since 2012, in order to ensure the smooth progress of the next step of the project, and to explore the coal seam and water content in front of it, we must adhere to the principle of "every excavation must be explored, and the first exploration must be followed by excavation". Before excavation, we must explore the coal, explore the water and drill holes. This drilling measure is specially prepared

II. Construction scheme

(a). Drilling design: according to the arrangement of the mining party, the construction of water exploration and drainage drilling will begin on April 20, 2014. Four boreholes are arranged, one for coal exploration in the middle and three for water exploration around. According to the roadway design, the exploratory holes are arranged in a fan-shaped manner. The designed drilling depth is 100m, and the vertical drilling position is 37.87m behind the c# point. The specific layout is shown in the chart

2. The cumulative quantities are based on the actual acceptance

(a) operation process and requirements 1. Zdy-800 full hydraulic tunnel drill is used for drilling parameters; The power of the supporting motor is 17.5kw, and the voltage level is 660V; The power supply switch is bqd-120 mining flameproof switch; Drill pipe Φ 50 750mm； The drill bit is Φ 75mm carbide steel drill bit

2. Rig installation (1). Carefully check the drill pipe, switch and other equipment of the rig on the ground to confirm that they are in good condition and qualified. After debugging, load them into the well. (2) Equipment and materials shall be transported from the ground to the construction site in strict accordance with the transportation management regulations. (3) Before operation, the construction team should be contacted in advance to cooperate with each other. (4) The underground electric fitter is responsible for connecting the power supply of the drilling rig according to relevant standards, and installing the drilling rig with the cooperation of the driller. (5) Clean and level the operation site, lay several layers of logs according to the operation requirements, and bind them firmly with 8# double strand lead wires. (6) Use a special lifting appliance to place the drilling rig stably on the track timber and adjust it to the direction required for construction drilling. (7) . fasten the four corners of the drill with telescopic pillars perpendicular to the roadway roof. (8) All rotating parts of machinery shall be equipped with protective railings and covers. (9) Measure the drilling angle with a slope gauge. (10) Set up the operation platform on one side of the drilling rig and place the drill pipe on the operation platform. (11) Turn the switch isolation handle to the forward rotation position. (12) Connect one end of the water supply hose to the water supply device of the drilling rig and the other end to the static pressure water pipe tee

3. Operation steps (1) preparation before drilling 1) fill the oil tank with clean oil (the oil should be about 2/3 above the middle of the oil level indicator after normal operation of the drill), and generally use 68 # anti-wear oil. 2) Check whether the fasteners of the drilling rig and all parts are fastened. 3) Fill the parts that need lubrication with lubricating oil and grease. 4) Check whether all oil pipes are connected correctly. 5) According to the arrow indicated, adjust the pump capacity of the auxiliary pump to the minimum position first, and then rotate it reversely. Adjust the pump capacity of the auxiliary pump to about 25%. 6) Place the function conversion handle of the auxiliary pump on the console at the pressure regulating valve position (that is, the front position). Other operating handles are placed in the middle position, and the back pressure adjusting handwheel (one-way throttle valve) is adjusted clockwise to the limit position. Specifically, the pressure reducing valve and overflow valve handwheel are adjusted to the minimum position. The motor variable handwheel is adjusted as required, generally within the range of medium speed displacement. 7) Open the stop valve on the oil tank, and do not start the motor until this valve is opened

(2) start-up operation 1) connect the power supply, test run the motor, and pay attention to whether the steering is consistent with the requirements of oil to invest limited financial resources in other more needed places to pump. 2) Start the motor, observe whether the oil pump operates normally (there should be no abnormal sound, and the oil return pressure gauge on the console should have an indication), and check whether each component has oil leakage. 3) Operate the auxiliary oil pump after idling for 3-5 minutes. If the oil temperature is too low, the idling time should be extended. When the oil temperature reaches about 20 ℃, the displacement can be adjusted to work. 4) The oil motor shall be tested in both forward and reverse directions, and the operation shall be normal and stable, and the reading of the system pressure gauge shall not be greater than 4MPa. 5) Repeatedly test the forward and backward of the rotator to eliminate the air in the oil cylinder until the operation is stable. At this time, the system pressure should not exceed 2.5MPa. 6) The opening and closing of the test chuck and the holder should be flexible and the action should be reliable. 7) Check whether the action direction of each working mechanism is consistent with the marking direction of the indicator. If it is inconsistent, replace the relevant oil pipes in time (forward, reverse, forward, backward, etc. of the rotator motor). 8) During the test run, if oil leakage is found in each part, stop the machine immediately and eliminate it in time

(3) drilling casing

drilling casing adopts secondary pipe: diameter 108mm, length 4m. Its function is to prevent the detection of high-pressure water area. When the pressure reaches and should not be lower than grade B2 to or greater than 2.0MPa, and the water surges rapidly, the high-pressure water valve on the 108mm casing should be closed in time to prevent the pump from insufficient drainage capacity

4. Drilling 1) insert a drill pipe from the rear end of the rotator, pass through the chuck, manually enter the holder through the tripping and feeding functions, and manually tighten the drill bit in front of the holder

2) manually screw on the water supply behind the drill pipe, connect the water pipe and prepare for drilling

3) first rotate, and then feed the drill pipe into the hole by the reciprocating movement of the rotator through tripping in and feeding in and pulling out the handle. Stop feeding when the tail of the drill pipe approaches the rear end of the auxiliary shaft of the rotator

4) adjust the rotation speed according to the specific situation of the site for pressurized or reduced pressure drilling

5) when one drill pipe ends, reduce the pressure at the bottom of the hole, stop feeding first, then stop rotating, stop water supply, and manually remove the water feeder

6) insert the second drill pipe from the rear end of the rotator, manually screw on the screw thread, boil the water in the water feeder, return to the rotator through tripping and pulling out the handle, repeat 4), 6) and 5), and then repeat the cycle in turn until the specified drill pipe is delivered

7) after the drilling is completed, stop the drilling rig and flush the drilling with water until the return water becomes clear

8) when unloading the drill pipe, stop the water supply, remove the water feeder, pull out the drill pipe by pulling out and feeding the lifting handle, stop when the joint to be unloaded is 250mm ~ 300mm out of the gripper, and turn the motor upside down to unscrew the drill pipe. (copper hammer must be used to knock the drill pipe when disassembling, and iron hammer is strictly prohibited)