Product Advantages
The Diamond Core Drill Bits for Concrete Coring device is used for gas extraction in coal mines. It mechanically expands the coal seam to release coal seam stress and extract gas. It is suitable for both soft coal seams and hard coal seams. It is applicable to hole-expanding and hole-making in the coal seam along the seam, through the seam in the bottom extraction lane, and downhole in the roof rock lane. Choose the appropriate mechanical hole-making device according to the coal seam conditions.
Working Principle
During normal drilling, the water pressure of the clean water pump station is less than 3Mpa (in order to avoid pressure fluctuations causing the knife arm to open in the non-expanding section, it is recommended to control the drilling pressure at 3MPa), and normal drilling is carried out; when expanding the hole, when the water pressure of the clean water pump station is 7MPa, the knife arm of the variable diameter mechanical hole making device begins to open, and as the pressure increases, the knife arm is fully opened to make holes, and the back and forth advancement speed should be slow, and reversal is prohibited.
Note: The clean water pump station is equipped with 315L/min, the pressure range is 0~16MPa; the high-pressure pipe pressure is not less than 16Mpa, and the drill rod and drill bit are equipped with 89-73 threaded drill rods and drill bits
Instructions for use
(1) After the hole is expanded and drilled, withdraw the drill 0.5m, keep the power head rotating, and slowly reduce the pressure of the clean water pump station to below 3MPa.
(2) When the hole is drilled, withdraw the variable diameter mechanical hole making device. After it is completely withdrawn, adjust the pressure of the clean water pump station, open the knife arm, clean the gear part and knife arm groove part of the mechanical hole making device, rinse it completely, and put it in the oil pool for maintenance to avoid rust and corrosion.
Precautions for use and maintenance
(1) It is forbidden to dismantle the variable diameter mechanical hole making device without permission.
(2) After use, the gear part and the arm groove of the drill rod body must be thoroughly cleaned to prevent coal slag from accumulating in the gear part and affecting the opening and closing.
Precautions
Precautions for operation during the operation of the complete set of equipment:
(1) When making a hole, set a warning line outside the water pump.
(2) The high-pressure rotary joint should be firmly installed with a pipe clamp.
(3) Observe the water level in the water tank and strictly prohibit water shortage.
(4) After the hole is made, turn off the pump, reduce the water pump pressure to 0MPa, and cut off the power supply after the pressure is completely released.
(5) Strictly implement the principle of not working during the moving process and not moving during the working process.
