How to choose the right pump for micro sprinkler irrigation and drip irrigation

Recently, some people questioned in the background of the irrigation network, how much power pump is needed for the use of micro-sprinkler irrigation in 50 mu of land?

For the choice of irrigation water pump, the type of water pump should be selected according to the water source condition. Secondly, the head and flow rate of the water pump are considered according to the irrigation area. The above conditions are determined. Micro-spraying and drip irrigation can achieve the desired effect. Here we will make a detailed analysis of this:

First, the type of pump

There are different options for different areas of agricultural irrigation pumps. There are three main types of agricultural pumps available: 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. The utility model has the advantages of small body shape, light weight, high efficiency, high efficiency and wide area, simple structure, convenient use and easy maintenance. The conveying medium is clear water or similar to clean water, and is suitable for irrigation and drainage of farmland in areas rich in surface water sources in the south. The centrifugal pump works by rotating the impeller to cause the water to undergo centrifugal motion. There are many models to choose from, and the range of flow and lift can be selected. It is the most widely used pump in agriculture. In the plain area, a lower centrifugal pump can be selected, a hill area can choose a moderate lift, and a high-altitude multi-stage centrifugal pump can be used in a high altitude area. Users should purchase according to local conditions, water source and water lifting height. The submersible pump is suitable for pumping water from deep water wells. It is mainly used for irrigation of farmland in the plain area where surface water is lacking in North China and other areas and irrigation in plateau mountains.

Second, the pump head

The so-called head refers to the required pressure, not a single lifting height. It is especially important to choose a pump. The pump lift is about 1.15 to 1.20 times the lift height. If the vertical height of a water source to the water is 20 meters, the required lift is about 23 to 24 meters. When selecting the pump, the head on the pump nameplate should be close to the required head. In this case, the pump is the most efficient and the use is more economical. However, it is not necessarily required to be absolutely equal. As long as the general deviation does not exceed 20%, the pump can work in a more energy-saving situation.

Choosing a pump with a head on the nameplate that is much smaller than the required head will often not satisfy the user’s wishes. Even if the water can be pumped, the amount of water will be pitifully small, and it will even become a useless pump. . Is it better to buy a pump with the highest lift? Actually it is not. If the pump with high lift is used for low lift, the flow will be too large, causing the motor to be overloaded. If the motor temperature rises for a long time, the winding insulation will gradually age and even burn the motor.

(1) The head is low, using a common centrifugal pump. The water spray micro-spray lift is the lowest, the working pressure of the belt is generally below 10 meters, the highest is 20 meters, plus the pipeline loss, the pump lift is only 15-25 meters. The ordinary micro-sprinkler or drip irrigation working pressure is about 20 meters, and the pump lift can be 25-40 meters. For the small family size (3-10 mu), the model of “one pump and one tube” is adopted, and the motor pump with the optional power of 1.1-2.2 kW, the diameter of 25-40 mm and the head of about 15 is in the absence of power line. Underneath, a gasoline engine pump can be used.

(2) The head is moderate, and the special pump for sprinkler irrigation is used. Generally used in field sprinkler irrigation, the irrigation unit is about 50 acres, the pump lift is 45 meters, the irrigation unit is about 150 acres, and the pump lift is 55 meters.

(3) The head is higher and the multi-stage pump is selected. Generally used in mountainous sprinkler irrigation, the head calculation is also simple, that is, the plain lift + the relative height of the mountain. If the mountain height is about 50 meters, the pump lift will be about 100 meters. Ordinary centrifugal pumps are not efficient for use when they are used for high lifts. When the lift is greater than 55 meters, a multi-stage pump can be selected, which is connected in series by multi-stage impellers, and the lift can reach more than 200 meters, and the efficiency is still the efficiency of the single-stage impeller, and will not decrease.

Third, the pump flow

The flow rate of the pump, that is, the amount of water discharged, each micro-spray or drip irrigation has a rated flow range. The flow required for installing micro-spray and drip irrigation, that is, the flow rate of each micro-sprinkler or dripper multiplied by the expected number of installations is required. Total flow. Generally, it should not be too large. Otherwise, it will cause problems such as squibs in the irrigation system, and it will increase the cost of purchasing pumps.

It should also be noted that the flow rate of the pump should match the specifications of the pipe.