Problems in design and installation of sprinkler i

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Problems in the design and installation of sprinkler irrigation system in sloping areas generally, it is a difficult task to make the sprinkler irrigation system in sloping areas not only meet the water requirements of crops, but also easy to manage. It is a challenging task to effectively solve the water demand of slope crops. Too little water will affect the growth of crops, and too much water will cause many other problems

the main challenge is how to meet the water demand for crop growth without generating surface runoff and eroding crops and the ground. The following gives 10 design, product selection and installation skills, which can effectively solve the problem of surface runoff in slope irrigation:

1. In order to reduce surface runoff, the system should select an irrigation timer that can control the irrigation time, i.e. a controller (such as Rain Bird E-class, esp-lx+ controller, etc.). Each program shall have at least 4 different start-up times. First, determine the time required for each station to generate surface runoff, so as to adjust each irrigation time. If necessary, different start-up times can be used to change the ground runoff generated due to the long operation time of the solenoid valves in each station, or high-grade controllers (such as rainbird esp-mc controller) can be selected. This controller can provide intermittent irrigation, that is, the total irrigation time is divided into several cycles, and sufficient time is left between each cycle to allow water to penetrate into the soil to avoid ground runoff

2. The main valve and flow sensor equipment are used to increase the system safety factor. When irrigating slopes, it is important to use the main valve and flow sensor. The main valve is set in front of the solenoid valve of each station and around the slope, which can reduce the pressure bearing time of the main pipeline. A closed main valve supplies water to the main pipeline only when it receives the controller signal. This equipment can improve the safety performance and reduce the probability of nozzle damage, pipe rupture and solenoid valve damage

the flow sensor can detect the flow change when the problem occurs. If properly calibrated, the sensor and the main valve will work together to shut down the system in case of additional flow, protect the slope crops and ensure the safety of the system

3. Using the reverse diaphragm solenoid valve can reduce the problems caused by the damage of the solenoid valve diaphragm. The internal structure of this valve is different from that of ordinary solenoid valve. When the solenoid valve diaphragm is damaged, it can effectively cut off the water flow. In other words, the reverse diaphragm valve is effective, because when it is not working, the diaphragm is in the "closed" state, which can cut off the water source. In general, the solenoid valve is in the "open" state when the diaphragm is damaged, and the water will constantly erode the crops before effective maintenance

4. Use equipment with pressure compensation or pressure regulation function to obtain the best spraying effect. When the model of the pressure regulator matches the performance in the manufacturer's manual, the pressure regulator installed on the solenoid valve can adjust the downstream working pressure. Under the appropriate working pressure, the nozzle is most likely to achieve effective and uniform spraying effect. If the nozzle pressure is lower or higher than the working pressure, the spraying effect is not good. As a result, crops are damaged and erosion may occur

it is the best way to use the sprinkler with built-in pressure compensation or pressure regulator, because the appropriate working pressure is directly applied to each sprinkler used by Dynesys without fusion clinical trials or spinal surgeons outside the United States (such as rainbird 1800 and uni spray sprinkler with pressure regulation function). The rotor pump can eliminate the atomization caused by high pressure, reduce the drift caused by wind, provide an optimal water drop displacement condition, and protect the growth of crops

5. Adjust the branch pipe spacing to compensate for the problems caused by the slope. For example, for a 1:2 slope, the spraying radius above the nozzle installation site can only reach 80% of its range, while the spraying radius below the nozzle can reach 120%. This concept is difficult for many people to understand because the area covered by the slope on the design plan of the irrigation project is smaller than what they actually do, and the effect of the slope cannot be correctly reflected from the map

therefore, the nozzle spacing along the branch pipe direction should remain unchanged. In the direction of slope, from the bottom of slope, the middle of slope to the top of slope, the distance between branch pipes shall be from small to large, and the distance between top nozzles shall be the range of nozzles

6. Arrange branch pipes along the contour line. When installing branch lines, make sure they are arranged along the contour line. If the branch pipe is installed incorrectly along the slope direction, the pressure imbalance will be caused by the change of height difference, resulting in the change of irrigation uniformity

in addition, the high-pressure area at the bottom of the slope will also reduce the service life of the sprayer and pipeline

7. The number of sprinkler heads in each round irrigation area should not be too large to reduce potential hidden dangers. When you increase the number of sprinklers in a certain area, the system pipeline and engineering structure will change. When the system is shut down, it may be damaged due to other reasons (such as water hammer). Therefore, it is generally not recommended to make the system larger, unless the system is installed with other protective equipment (such as pressure reducing valve, inlet and exhaust valve, etc.) to avoid some potential hazards

8. Limit the number of sprinkler heads in each round irrigation area to improve the spraying effect. Considering the influence of plant varieties, rainfall, sunshine, wind direction and other meteorological factors on different areas of the slope, the slope is divided into multiple irrigation areas to fully meet different requirements. If different plants are mixed in an irrigation area, it is difficult to make crops grow healthily

9. Divide the full circle sprinkler and adjustable angle sprinkler into different irrigation areas. Arrange the adjustable angle sprinkler in an independent round irrigation group, so that the rainfall can be the same as that of the round sprinkler round irrigation group, and the irrigation can be uniform by adjusting the irrigation time. A better way is to select the nozzle with matching rainfall intensity, that is, when different spraying angles are changed, the rainfall intensity of the nozzle remains unchanged (for example, yujinqiu, senior engineer of yuniao 1800 Series M Zhejiang architectural science design and Research Institute Co., Ltd., analyzed and called PR nozzle), which can ensure that the rainfall of all nozzles is the same and the irrigation uniformity is high

10. Install the overflow valve to avoid erosion. Ensure that the overflow valve is properly installed. When the terrain elevation difference changes, when the partition solenoid valve is closed, the water in the high pipe can be prevented from flowing out of the low nozzle. This will reduce the erosion of the green area or the crops around the slope. Before installation, check whether the nozzle has a built-in overflow valve, so as to reduce the need to install a separate overflow valve under each nozzle

note: because many slope greening plants do not use lawn, it is recommended to use 6 "(15cm) or 12" (30cm) lifting sprinkler to attract high-level R & D personnel not to use rocker sprinkler with riser, not only because the lifting sprinkler improves the working conditions, but also has good concealment and is not vulnerable to human damage

effective slope irrigation includes early planning and design, appropriate installation and reliable maintenance and maintenance technology. If these three problems can be well solved, many troubles in use, maintenance and capital can be reduced, and the crops on the slope can grow healthily

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