How to identify slurry pump performance?
The expression of the head, flow and power of the pump and its guidance to the head, flow and power of the slurry pump are important parameters for investigating the performance of the pump:
1. Flow rate The flow rate of a slurry pump is also called water delivery volume, which refers to the amount of water delivered by the pump per unit time. It is represented by the symbol Q, and its units are liters/second, cubic meters/second, and cubic meters/hour.
2. Head The head of a slurry pump refers to the height at which the pump can lift water. It is usually represented by the symbol H and its unit is meter. The head of the slurry pump is based on the center line of the impeller and consists of two parts. The vertical height from the center line of the slurry pump impeller to the water surface of the water source, that is, the height at which the slurry pump can suck up the water, is called the suction lift, referred to as the suction lift; the vertical height from the center line of the slurry pump impeller to the water surface of the outlet pool, that is, the pump can press the water up The height of is called pressure head, or pressure range for short. That is, pump head = suction head and pressurized water head. It should be pointed out that the head marked on the nameplate refers to the head that the pump itself can generate, and it does not include the loss head caused by the frictional resistance of the pipeline water flow. When choosing a slurry pump, be careful not to ignore it. Otherwise, there will be no water.
3. Power In unit time, the amount of work done by the machine is called power. It is usually represented by the symbol N. Commonly used units are: kg·m/s, kilowatts, horsepower. Usually the power unit of the electric motor is expressed in kilowatts; the power unit of the diesel engine or gasoline engine is expressed in horsepower. The power transmitted by the power machine to the shaft of the water pump is called shaft power, which can be understood as the input power of the water pump. Generally speaking, the power of the slurry pump refers to the shaft power.
Due to the frictional resistance of the bearing and the packing; the friction between the impeller and the water when rotating; the vortex of the slurry flow in the pump, the backflow of the gap, the inlet and outlet, the impact of the mouth and so on. Part of the power is inevitably consumed, so the water pump cannot completely convert the power input by the power machine into effective power, and there must be a power loss, that is, the sum of the effective power of the water pump and the power loss in the pump is the shaft power of the water pump.
There is also a difference between the matching power of the slurry pump and the shaft power. It is larger than the shaft power. The main consideration is that the pump and the power machine are matched to form a unit. There must be a transmission device in the middle, and its operation will inevitably consume some power. In addition, in order to ensure the safe operation of the unit and prevent the power unit from being overloaded, there is room for the supporting power. In this way, a safety reserve factor K must be considered, K=1.5-2. Generally speaking, when the pump shaft power is small, the K value Choose a larger value; when the shaft power is large, choose a smaller K value.