1. Flow is one of the important performance data of the pump, it is directly related to the production capacity and transport capacity of the entire device. Such as the design process of the design of the pump can be calculated normal, minimum, maximum three kinds of flow. When selecting a pump, the maximum flow is based on, taking into account the normal flow, in the absence of maximum flow, it is often desirable to the normal flow of 1. 1 times as the maximum flow.
2. The device system is required to pump head is another important performance data, the general need to use the 10% - 5% margin after the lift to the selection.
3. Fluid properties, including the name of the liquid medium, physical properties, chemical properties and other properties, physical properties have temperature C density D, the viscosity u, medium diameter of solid particles and gas content, which involves the system's head, effective cavitation margin calculation and the right pump type: chemical properties, mainly refers to the liquid medium corrosive and toxic chemicals, the selection of pump materials and use is the important basis of the shaft seal type.
4. Is system device of pipeline layout conditions refers to send liquid height send fluid distance to send fluid, such as suction side of the minimum level, discharge side of the maximum liquid level and some data and piping specifications and its length, material, pipe specifications, quantity, etc., in order to carry on system comb head calculation and NPSH check.
5. Operating conditions, such as liquid operation T saturated steam power P, inhalation of lateral pressure PS (absolute), discharge side of the container pressure PZ, altitude, ambient temperature operation is the gap or continuous, the location of the pump is fixed or may shift.
