According to the process flow and water supply and drainage requirements, five aspects should be considered, including liquid delivery volume, device head, liquid properties, pipeline layout, and operating conditions.
1. Flow rate is one of the important performance data for pump selection, which directly affects the production and transportation capacity of the entire device. If the design institute can calculate the normal, small, and large flow rates of the pump in the process design. When choosing a pump, the high flow rate should be taken as the basis, while considering the normal flow rate. When there is no high flow rate, it is usually recommended to use 1.1 times the normal flow rate as the high flow rate.
2. The head required for the installation system is another important performance data for selecting pumps, and generally the head should be selected by amplifying the margin by 5% to 10%.
3. The properties of liquids include the name of the liquid medium, physical properties, chemical properties, and other properties. Physical properties include temperature, density, viscosity, solid particle diameter, and gas content in the medium. This involves the system's head, effective cavitation allowance calculation, and the appropriate type of pump. Chemical properties mainly refer to the chemical corrosiveness and toxicity of the liquid medium, which are important criteria for selecting pump materials and choosing the type of shaft seal.
4. The pipeline layout conditions of the device system refer to the liquid delivery height, distance, direction, suction side * * low liquid level, discharge side * * high liquid level, and other data, as well as pipeline specifications and their lengths, materials, pipe fittings specifications, quantities, etc., in order to calculate the system head and verify the cavit
