Through analysis and understanding of the composition and function of mine explosion-proof pumps for underground drainage equipment in coal mines, the main noise sources of mine explosion-proof water pumps and the main causes of noise are found to provide a basis for controlling noise sources and reducing noise.
Take the MD type centrifugal water pump of the main drainage equipment in the coal mine as an example. MD type mine explosion-proof water pump is mainly composed of water pump, electric motor, starting equipment, drainage pipeline, pipeline accessories and instruments.
The main reason for the noise of mine explosion-proof water pump for underground drainage equipment in coal mine
(1) The impeller is the main part of the MD type mine explosion-proof water pump. When rotating, friction between sand and mineral water, and friction with fixed parts will cause noise; cavitation of the pump and unbalanced balance plate will also produce Vibration and noise. In addition, the loosening of the foundation bolts, the misalignment of the center of the motor and the center of the water pump, the bending of the pump shaft, the excessive wear of the bearing, and the imbalance of the water pump rotor will cause vibration and noise. The water pump is also affected by the fluctuation of input torque and load torque, which causes torsional vibration and noise.
(2) The unbalanced motor rotor will produce vibration and noise; at the same time, the current produced by overload is louder. The starting device cooperates with the electric motor to start, which will produce electric current.
(3) The drainage pipeline is used to transport mineral water and drain it to the ground. If there is air in the pipeline, it will cause vibration and noise in the pipeline. If the suction pipe is too high and there is air, it will produce vibration and noise. Choose a cast pipe with a smooth inner wall as the drain pipe, and fix the drain pipe firmly to reduce noise.
(4) The water filter in the pipeline attachment is used to prevent debris in the mineral water from entering the pump, which will increase the water absorption resistance. The bottom valve is to prevent the water from being poured into the pump and the suction pipe before the pump is started, and the water stored in the suction well after the pump is stopped. The bottom valve will increase the resistance of the suction pipe, causing vibration and noise; the bottom valve is blocked by debris, causing the water pump to run dry and generate noise. The regulating valve is used to adjust the head and flow of the water pump. The gate valve is opened too fast and the flow is suddenly too high to make the pump produce noise.
(5) Resonance and noise are caused by each rotating part due to low manufacturing accuracy and wear. The bearing of the water pump has a large load, and is easy to wear and roll and crack, and the noise will increase. Once a problem is found, it should be replaced in time.
