The pump flow, the water generally should not be chosen too large, otherwise it will increase the costs of purchasing the water pump. Should be selected as needed, such as family use self-priming pump, flow rate should be selected smaller if user submersible pumps for irrigation, it may be appropriate to select traffic.
1) to local conditions to buy water pumps. Commonly used agricultural pump has 3 types, namely, centrifugal, axial and mixed flow pumps. Centrifugal pump head high, but little water, applied to mountain and well irrigation area; large amount of axial flow pumps water, but the head is not too high, apply plain; mixed flow pumps water and between the head of centrifugal and axial-flow pump, suitable for plain and hilly areas. Users to base conditions, water sources and water level to purchase.
2) to appropriate standard selected pumps. After you determine the type of pump, taking into account their economic performance, paying particular attention to head and flow of the water pump and engine choices. It must be noted that pump signs marked on the head (total lift) when used with water lift (actual head) is different, this is due to water flow through pipes and near the pipeline will have a certain resistance to damage. Therefore, the actual total head lift than low-10%-20%, water will be reduced. So, actual using Shi, only by signs by note head and flow of 80%~90% estimates, pump supporting power of select, can by signs Shang indicate of power select, to makes pump started quickly and using security, engine of power also can slightly is greater than pump by needed power, general high out 10% around suitable; if has has power, purchase pump Shi, is can by engine of power purchase and of phase supporting of pump.