For the selection of irrigation pumps, firstly choose the type of pump according to the water source, and then consider the pump head and flow according to the irrigation area, determine the above conditions, micro-spray and drip irrigation can achieve the desired effect. Let's make a specific analysis of this:

One, the type of water pump.

There are different options for agricultural irrigation pumps in different regions. There are three main types of agricultural irrigation pumps to choose from: mixed flow pumps, centrifugal pumps, and submersible pumps. The flow and head of the mixed flow pump are between the centrifugal pump and the axial flow pump. Small size, light weight, high efficiency, wide high efficiency zone, simple structure, convenient use and easy maintenance. The conveying medium is clean water or similar to clean water, which is suitable for irrigation and drainage of farmland in areas with abundant surface water sources in the south. Centrifugal pumps work by using the rotation of the impeller to make the water produce centrifugal movement. There are many models to choose from, and the range of flow and head options is also large. It is the most widely used water pump in agriculture. You can choose a centrifugal pump with a lower head in plain areas, a moderate head in hilly areas, and a multi-stage centrifugal pump with higher head in high altitude areas. Users should choose according to local conditions, water sources and lifting heights. Submersible pumps are suitable for pumping water from deep-water wells, and are mainly used for irrigation of farmland in plain areas such as North China where surface water is lacking and irrigation in plateau and mountainous areas.

Second, the head of the pump.

The so-called head refers to the required pressure, not a single lifting height. It is particularly important to know this point for the selection of a water pump. The pump lift is approximately 1.15 to 1.20 times the lifting height. For example, the vertical height from a water source to the place where the water is used is 20 meters, and the required lift is about 23 to 24 meters. When selecting a water pump, the head on the nameplate of the pump should be close to the required head. In this case, the pump has the highest efficiency and will be more economical to use. But it is not necessarily required to be absolutely equal. Generally, as long as the deviation does not exceed 20%, the pump can work in a more energy-saving situation.
Choosing a pump whose head on the nameplate is much smaller than the required head will often fail to meet the user's wishes. Even if it can pump water, the water volume will be pitifully small, and it will even become a useless "idle pump". . Is the higher the pump lift the better? In fact, it is not. If the pump with high head is used for low head, the flow will be too large, causing the motor to be overloaded. If the motor is running for a long time, the temperature of the motor will rise, the winding insulation layer will gradually age, and even the motor will be burned.

1. With lower head, use ordinary centrifugal pump. The micro-jetting head of the water belt is the lowest, and the working pressure of the belt is generally below 10 meters, and the highest is 20 meters. In addition to the pipeline loss, the pump head is only 15-25 meters. The working pressure of ordinary micro-sprinkler irrigation or drip irrigation is about 20 meters, and the pump head can be 25-40 meters. For a small family (3-10 mu), the "one pump, one tube" mode is adopted, and the optional power is 1.1-2.2 kilowatts, the diameter is 25-40 mm, and the head is about 15 motor water pumps. When there is no power line Down, gasoline engine water pump can be used.

2. Moderate head, use special pump for sprinkler irrigation. Generally used in field sprinkler irrigation, the irrigation unit is about 50 acres, and the pump head is 45 meters; if the irrigation unit is about 150 acres, the pump head is 55 meters.

3. For higher head, choose multi-stage water pump. Generally used in mountainous sprinkler irrigation, the head calculation is also simple, that is, plain head + mountain relative height, such as the height of the mountain is about 50 meters, the pump head must be about 100 meters. When the ordinary centrifugal pump is used for high head, the efficiency is low, so it is not suitable to be used. When the head is greater than 55 meters, a multi-stage pump can be used, which

The multi-stage impellers are connected in series, and the head can reach more than 200 meters, and the efficiency is still the efficiency of a single-stage impeller and will not be reduced.

Three, water pump flow.

The flow rate of the pump, that is, the amount of water, each type of micro-sprinkler or drip irrigation has a rated flow range. The installation of micro-sprinkler or drip irrigation requires a flow rate, that is, the flow rate of each micro-sprinkler or dripper multiplied by the expected number of installations is what is needed Total flow. It is generally not appropriate to choose too large, otherwise it will cause problems such as pipe bursts in the irrigation system, and at the same time will increase the cost of purchasing water pumps.