Classification of water pump selection
1. According to the working principle and structure of the pump, it can be divided into vane pump, positive displacement pump (and other types of pumps), such as jet pump, air lift pump, electromagnetic pump, rotary vane vacuum pump, water ring vacuum pump, etc. Vane pump, such as centrifugal pump, vortex pump, mixed flow pump, refueling pump, screw pump, etc. Positive displacement pump, such as reciprocating pump, rotor pump, etc. Two types of reciprocating pumps: electric pump, steam pump, electric pump: plunger (piston) pump, diaphragm pump, etc Measuring pump rotor pump: gear pump, screw pump, Roots pump, sliding vane pump, etc.
2. According to the medium, it is divided into: clean water pump, sewage (sewage) pump, oil barrel pump, corrosion-resistant pump, diaphragm pump, magnetic pump, sewage pump, centrifugal pump, screw pump, oil pump, etc;
3. From the perspective of usage and installation methods, it can be divided into diaphragm pumps, oil pumps, refueling pumps, magnetic pumps, barrel pumps, hand pumps, centrifugal pumps, multi-stage pumps, etc.
After determining the design flow rate and design head of the water pump station, relevant technical charts can be used to determine the pump model and specifications. The method is to use the pump performance specification table to select the pump type. The pump factory provides this table in the product catalog, and the performance of each model in the table has three rows of data. Which one should prevail? Generally, the design flow rate and design head should be consistent with the values listed in the middle row of the performance table, Or it may be close, but must fall within the range of the upper and lower rows, because this range is the high-efficiency area for water pump operation. This model of water pump is considered to meet practical needs, and the water pump is considered selected. Use the pump selection table to select the pump type based on the determined design head and design flow rate. In the selection table, check the horizontal head to find the head value that matches or is close to the design head; Find the flow value that is consistent with or close to the design flow rate in the vertical header, intersecting vertically and horizontally in small blocks, which indicate the model of the water pump and preliminarily select the pump type.
However, sometimes both pump types meet the design requirements. In this case, these two pump types can be compared for technical and economic analysis, and then one suitable pump type can be selected. This method of selecting a water pump is relatively simple and fast. Using a comprehensive spectrum of water pump performance to select the pump type, the working areas of centrifugal pumps, axial flow pumps, mixed flow pumps, and slurry pumps are all comprehensively drawn on the same graph, forming a comprehensive spectrum of agricultural water pump series. The drawing of this graph is relatively complex, but it is more convenient to use.
Based on the determined design flow rate and design head, on the type spectrum, first search for several types of water pumps that meet the head requirements with unequal flow rates on the vertical axis using the design head, and then determine which type of water pump to choose based on the design flow rate on the horizontal axis. If a single pump fails to meet the requirements when the design flow is large, multiple machines can be considered for operation, but attention should be paid to using the same model of water pump as much as possible to facilitate construction installation, management and maintenance.