The basic components of the Dongfeng water truck are the anti-rust tank, power take-off, driveshaft, special self-priming sprinkler pump, pipe network, spray outlet, the main engine driving the gearbox during the operation of the sprinkler. The power device drives the sprinkler pump. The sprinkler pump generates power and sprays the liquid inside the tank through the pipe network. Therefore, the water pump is equivalent to the heart of the sprinkler and affects the effectiveness of the sprinkler.
Therefore, in order to ensure that the pump has good self-priming performance, the following conditions must be met:
1. Before the pump works, the liquid storage in the pump must be higher than the pump shaft. Therefore, an upward bent pipe must be connected to the pump inlet and then a horizontal pipe and quick coupling. The centerline of the quick coupling must be higher than the centerline of the pump shaft by 300 Mm.
2. The imported piping system must ensure no air leakage and good sealing performance.
3. The suction head of the suction pipe must be submerged underwater to prevent air from being sucked into the pipe.
4. When connecting the outlet pipe to the pump outlet, ensure that the length of the straight pipe is ≥200 mm before connecting the elbow pipe.
5. There must be a filter tee in the middle of the water inlet pipe to ensure that no impurities will damage the precision parts of the pump before the water enters the pump.
The sprinkler series pump adopts a centrifugal self-priming structure, and there should be an appropriate amount of liquid in the pump. After the pump is started, the impeller rotates, and negative pressure is formed at the inlet of the impeller. The gas in the suction pipeline is mixed with the liquid in the pump and enters the gas-liquid separation chamber through the press-out chamber. Due to the difference in the specific gravity of the gas and liquid, the gas rises and separates from the liquid and is discharged from the outlet pipe. The liquid sinks in the gas-liquid separation chamber. After many cycles, the gas in the suction pipe is drained and filled with liquid to complete self-priming.
