What basic data are needed for self-balancing multi-stage pump selection?
Basic data of self-balancing multistage pump selection:
1. The characteristics of the conveying medium: medium name, specific gravity, viscosity, corrosiveness, toxicity, etc.
2. The particle diameter and content of the solid contained in the medium.
3. Medium temperature: normal use temperature and instantaneous limit temperature (℃)
4. The required flow rate:
General industrial pumps can ignore the leakage in the piping system in the process, but the impact on the flow rate when the process changes must be considered. If the pump is used to transport water in an open channel, leakage and evaporation must also be considered.
5. Pressure: suction tank pressure, discharge tank pressure, pressure drop in the piping system (head loss)
6. Piping system data (pipe diameter, length, type and number of piping accessories, geometric elevation from suction tank to pressure tank, etc.)
Determine the flow and head of the self-balancing multi-stage pump selection
1. Determination of flow rate a. If the minimum, normal, and maximum flow rates have been given in the production process, the maximum flow rate should be considered. If only the normal flow rate is given in the production process, a certain margin should be considered.
For high-flow low-head pumps with ns>100, the flow margin is 5%; for small-flow high-lift pumps with ns<50, the flow margin is 10%; for pumps with 50≤ns≤100, the flow margin is also 5. %. For pumps with inferior quality and poor operating conditions, the flow margin should be 10%. If the basic data only gives weight flow kg/h, it should be converted to volume flow m3/h.
2. Determination of the full head a, actual height, b, actual distance, c, pipeline (including valve, elbow) loss, D pressure of the closed vessel, etc. 3. Determine the power and speed of the pump according to the head and flow.
