1. Excellent hygiene performance: The pipe material is made from polyolefin, a polymer whose molecules consist solely of carbon (C) and hydrogen (H) elements. Both the primary and auxiliary materials fully meet hygiene standards, exhibit outstanding corrosion resistance, and remain chemically inert toward all ions present in water, ensuring they won’t rust or corrode. 2. Low hydraulic resistance: The inner surface of straight pipes is exceptionally smooth, preventing scale buildup altogether. As a result, frictional resistance in PP pipes is significantly lower than that of metal pipes. Moreover, when connecting pipe fittings, the cross-sectional area remains unchanged, leading to a lower local resistance coefficient compared to metallic pipelines. 3. Recyclable waste materials: Both pipe and fitting scraps can be collected, cleaned, and recycled directly into new products—such as additional pipes and fittings. This process ensures zero environmental pollution during manufacturing and installation, making PP pipes an eco-friendly building material. 4. Superior thermal insulation and energy efficiency: With a thermal conductivity of just 0.21 W/(m·K), PP pipes are nearly 200 times less conductive than steel pipes. In most cases, this translates to significant energy savings when insulating hot-water pipelines. Additionally, PP pipes experience minimal expansion forces even under temperature fluctuations, making them ideal for concealed installations embedded within walls or floor surfaces. 5. Limitations of PP pipes: a) Compared to metal pipes, PP pipes have inferior rigidity and impact resistance, making them prone to damage during storage, transportation, and installation. b) PP pipes also have a relatively high linear expansion coefficient—ranging from 0.14 mm/(m·K) to 0.16 mm/(m·K)—which necessitates careful consideration in design. They are best suited for concealed installations; if exposed or not installed underground, special measures must be taken to prevent deformation caused by thermal expansion. 6. Outstanding heat resistance and long service life: PP pipes can withstand operating temperatures up to 95°C and maintain stable performance at continuous use temperatures of 70°C under a pressure rating of 1.0 MPa—well-suited for hot-water supply applications. Under these conditions, the expected service life exceeds 50 years, while at ambient temperatures, the lifespan can extend beyond 100 years. 7. Easy installation and reliable connections: PP pipes boast a straightforward production process with minimal equipment investment, and their lightweight nature—weighing only 1/9th that of steel pipes and 1/10th that of copper pipes—greatly reduces labor intensity during construction. Furthermore, thanks to the unique raw materials used in their manufacture, PP pipes offer excellent hot-melt capabilities, enabling quick, secure, and durable connections. Importantly, the strength of the joint typically surpasses that of the pipe itself.

PP pipes boast features such as high-temperature resistance, convenient pipe connections (including hot-melt, electrofusion, and fitting-based joints), and recyclability, making them ideal for applications like agricultural irrigation systems, building water supply systems, heating networks, and chemical industry pipelines. Based on different polymerization processes, PP pipes can be categorized into homopolypropylene (PP-H), block copolymer polypropylene (PP-B), and random copolymer polypropylene (PP-R). While PP-H pipes are limited by their brittleness at low temperatures, they are gradually being replaced by PP-B and PP-R pipes in certain application areas. Notably, PP-B pipes are primarily used in cold-water systems and underfloor heating setups, whereas PP-R pipes enjoy even broader usage across various industries. In addition to the typical characteristics of plastic pipes, PP-B and PP-R pipes also offer exceptional advantages: excellent hygiene performance, superior heat resistance combined with thermal insulation for energy efficiency, easy installation with reliable connections, fully recyclable materials, simple equipment requirements, straightforward and easily controlled production processes, and flexible pipeline layouts.

A sprinkler irrigation machine is an irrigation device that winds a traction PE pipe onto a winch. It uses pressurized water from the sprinkler system to drive a water turbine, which in turn rotates the winch via a speed-reducing mechanism. This motion automatically moves the sprinkler carriage while simultaneously spraying water across the field. **Applications** The reel-type sprinkler can efficiently irrigate large areas of farmland and allows users to precisely control the amount of water sprayed through adjustable nozzles, making it an ideal choice for water-saving irrigation in agricultural settings. Additionally, it’s well-suited for applications requiring both irrigation and dust suppression, such as power plants, ports, sports fields, and urban green spaces. **Operating Principle** This reel-type sprinkler features a water-turbine-driven power system. Its design incorporates a large cross-section combined with low-pressure principles, enabling high recovery speeds even at minimal flow rates. The water turbine’s rotational speed is transmitted via a two-speed belt drive connected to the turbine shaft, leading into a gearbox. After reducing the speed, a chain-drive mechanism amplifies the torque, ultimately rotating the winch and facilitating the automatic retraction of the PE pipe. Meanwhile, the high-pressure water exiting the turbine flows directly through the PE pipe to the sprinkler heads, where it is evenly dispersed into fine droplets that gently fall over the crops. As the PE pipe moves, the sprinklers continue to operate continuously without interruption. **Maintenance and Care** After each irrigation session, the reel-type sprinkler should undergo routine maintenance according to the manufacturer’s instructions. At the end of the irrigation season, ensure all accumulated water inside the machine is drained, and rubber walking wheels should be lifted off the ground. For newly installed or majorly repaired units, a test run is recommended before full-scale operation. Before starting the sprinkler, carefully inspect all components: verify that sprinkler heads are securely attached, flow channels are clear and unobstructed, heads rotate smoothly, directional switching functions reliably, spring tension is appropriate, and all parts are present and intact. Check that pipes are fully functional, control valves and safety devices operate freely and flexibly, sealing rubbers remain soft and elastic, measuring instruments display clear readings with responsive needles, connectors are tight, cables show no damage, and sensor components move freely. When initiating the sprinkling process, gradually open the water valve, start the sprinklers one by one, and slowly adjust the pressure until it reaches the nozzle’s rated level—never activate all sprinklers simultaneously. To stop spraying, close the water valves gradually, avoiding simultaneous shutdown of all sprinklers. Ensure electrical connections are secure, safe, and properly grounded; confirm that fuses match specifications, gauges display accurate readings, and wires/cables are undamaged. Moving parts should operate smoothly, while handles and buttons function reliably and intuitively. Lubrication points must be regularly serviced with appropriate oils. Sprinklers should be correctly and firmly installed, water delivery lines must remain unobstructed, braking and protective mechanisms must be reliable, tire pressure must meet standards, and during initial water tests, pipe joints must maintain secure seals without leaks. Finally, clear any obstacles in the field that could interfere with operations. When supplying or stopping water, always open or close valves and taps slowly. During operation, ensure the following conditions are met: 1. Pressure at both the beginning and end of the pipeline remains within the designed range. 2. Moving parts operate smoothly without unusual noises. 3. Seals remain leak-free. 4. Sprinklers perform optimally. If any malfunction occurs, address it promptly—never attempt to force the equipment into operation. After applying fertilizers, thoroughly flush the system to remove residues. Once irrigation is complete, drain any remaining water from the pipes. For electric-powered models, disconnect the power supply entirely. If the sprinkler will remain idle for an extended period, clean and flush the entire system, removing sediment, debris, and accumulated water from pumps and pipes. Clear away dirt and weeds from moving parts, and apply rust-prevention treatments to vulnerable components. **Application in Field Crops** In China, agricultural irrigation accounts for 70%–80% of total water consumption, with field crops (such as wheat, corn, and sweet potatoes) consuming 50%–60% of this irrigation water. Therefore, prioritizing water conservation efforts on field crops is crucial. Currently, traditional methods like furrow and surface irrigation dominate, with furrow irrigation still holding significant market share. While piped irrigation represents a notable step forward in water efficiency compared to surface irrigation, it only enhances the overall efficiency of the distribution system—leaving field-level water-use efficiency largely unchanged. Fixed sprinkler systems, though highly effective in conserving water, face challenges due to their incompatibility with conventional farming practices, limiting their widespread adoption. Similarly, semi-fixed and mobile sprinkler systems struggle to gain broader acceptance because of their cumbersome operation and management requirements. To explore optimal water-saving irrigation strategies for large-scale crops, Feicheng City has invested over 1.5 million yuan since 1996, introducing more than ten advanced reel-type sprinkler machines capable of international standards. These machines have been deployed across 333 hectares of field crops, yielding remarkable results. **Planning and Design of Reel-Type Sprinkler Irrigation Areas** 1. **Power Supply:** Select an appropriate pump model based on the sprinkler’s required flow rate and inlet pressure. 2. **Land Planning:** Scientific land planning is essential for effectively utilizing this cutting-edge equipment. To maximize efficiency, the project area underwent comprehensive reorganization, including adjustments to crop layouts and planting patterns. By aligning crop orientations with the sprinkler’s spray radius and reserving dedicated pathways between fields, equitable land distribution among farmers was achieved, laying a solid foundation for seamless equipment operation. 3. **Field Infrastructure Integration:** - **Water Channel System:** Install reservoirs at key intersections of operational and production paths. The capacity of these reservoirs is typically designed to accommodate the sprinkler’s water output, usually around 20 cubic meters.To prevent the reservoir from overflowing, a long-vine gourd-like system was created by connecting multiple reservoirs in series via pipes, with pipe inlets and outlets positioned just 5 centimeters above the pool bottom. ② Integrated pump-and-motor setup: To accommodate the continuous movement of the sprinkler system, an all-in-one diesel-powered pump-and-motor unit—specifically a tractor-driven pressurized pump—was adopted in practice. ③ PE pipe traction method: To minimize bending resistance in the PE pipes and ensure smooth, uniform retraction while preventing kinks or misalignment, a powered, fixed traction approach was implemented. This involves positioning a tractor equipped with a compact winch at the end of the operational pathway, directly opposite the sprinkler unit. The operator then pulls out a steel cable connected to the reel, attaching it to the PE pipe as it’s pulled toward the designated location. Once in place, the sprinkler cart is hitched up, and operations can begin. This traction method offers significant advantages: it eliminates the risk of tractors damaging crops or soil, keeps the PE pipes perfectly straight with minimal bending, and simplifies the overall operation process. **Application Results** Since the introduction of the reel-type sprinkler system, it has played a crucial role in ensuring bountiful agricultural harvests even during severe drought years, delivering remarkable economic benefits: ① Water-saving efficiency: Compared to traditional canal irrigation, it saves 47% of water; when compared to piped irrigation systems, it still achieves a 9% water-saving advantage. ② Yield enhancement: Crop production increases by 25% relative to canal irrigation and by 6% compared to piped systems. **Management Approach** Internationally, it is widely acknowledged that 50% of the potential for water-efficient irrigation lies in effective management practices. To ensure optimal performance and maximize the benefits of the sprinkler system, a dedicated Water-Saving Irrigation Company was established. This company enjoys independent legal status, fully responsible for civil and legal liabilities, and operates under a corporate-style management model focused on profitability. Guided by the principle of providing high-quality services to farmers at modest profit margins, the company prioritizes public welfare. Each irrigation service is delivered only after signing a formal agreement with the beneficiary households, strictly adhering to the terms outlined in the contract. Charges are limited to covering energy consumption, labor costs, and equipment depreciation—no additional fees are ever imposed. To maintain operational excellence, the company has implemented rigorous internal management protocols, fostering continuous financial growth and sustainable development. The reel-type sprinkler system delivers multiple benefits, including water conservation, energy efficiency, yield increases, land savings, and labor reductions. Moreover, crops irrigated using this system no longer require raised field borders, boosting land utilization rates by up to 10%. It is particularly well-suited for large-scale field crops such as wheat, corn, soybeans, and vegetables, making it an ideal irrigation solution for promoting intensive agricultural production and management. As a result, this system is highly recommended for widespread adoption across diverse farming regions.

The biggest challenge facing agriculture is irrigation—agricultural land is often vast, making it particularly difficult to evenly apply pesticides and water to crops. Fortunately, the development of agricultural machinery like sprinkler systems and sprayers has effectively addressed this issue. A sprinkler system features a rotating platform supported by upright posts mounted on a wheeled frame. A water supply hose is coiled around the platform, with one end securely fastened to the reel and connected via a flexible pipe to a hollow shaft inside the platform. The other end of the hose links to a spray gun through a rigid pipe attached to the gun’s carriage. Meanwhile, the outlet of a water turbine installed on the central post connects directly to the hollow shaft at the platform’s axis. The turbine is equipped with an inlet pipe connection, and its output shaft drives a driven pulley on the gearbox via a belt. Finally, the driven sprocket on the gearbox’s output shaft meshes with a gear ring fixed to the rotating platform. This sprinkler system utilizes a V-belt drive system, requiring the power unit’s main shaft and the pump to be aligned parallelly. The pulleys must be precisely aligned, with their center distance no less than twice the sum of their diameters. When connecting the pump to the power unit, ensure they share a common base and use a claw-type flexible coupling. Additionally, pay close attention to maintaining proper concentricity between the power unit’s main shaft and the pump’s shaft. The pump should be installed at a height that is 1–2 meters lower than the allowable suction vacuum height, measured from the water surface in the intake tank. Ensure the ground beneath the pump installation area is firm and stable to prevent collapse or sinking into the soil. When installing the water inlet pipeline, take extra care to prevent air leaks. The filter screen must be fully submerged in water, positioned about 30 cm below the water surface, while maintaining a safe distance from both the tank bottom and walls to avoid drawing in sediment, debris, or air. During the installation of the water delivery hoses, avoid friction against sharp objects like stones or tree bark, and steer clear of areas where they might get crushed by vehicle wheels or trampled by pedestrians. Never allow the hoses to come into contact with moving machine parts. When transporting hoses, roll them neatly into coils rather than dragging them on the ground. For rigid pipes, disassemble them into individual sections before handling; never attempt to move multiple sections together, as this could lead to wear, damage to the pipes, or failure of the fittings. Also, protect the pipes from direct sunlight and rain to prevent plastic degradation or aging. Before setting up the spray boom, position it horizontally on the ground, ensuring the boom joint faces are perfectly level for smooth rotation of the spray nozzles. Once properly aligned, secure the boom firmly in place. Attach the spray nozzles to the boom, checking that each nozzle rotates freely. Adjust the tension of the rocker arms to ensure optimal operation, and lubricate all moving parts with a small amount of oil. Finally, clean and securely connect the quick-connect fittings. Before starting the pump, verify that the pump shaft rotates smoothly and in the correct direction without any signs of jamming, unusual noises, or other abnormalities. For centrifugal pumps, always fill the pump casing completely with water prior to startup. Only after the entire water supply line and pump body are thoroughly primed can the pump be activated.

From the perspective of irrigation science research, is sprinkler irrigation suitable for use under windy conditions? If you were to carry out irrigation in such conditions, what would your countermeasures be? Let’s discuss this topic. ### I. Wind Speed and Wind Force Let me explain and analyze the relationship between wind speed and wind force for everyone. I recall a science class from my school days—back then, China also had some informal, verbally based methods for determining wind levels. ### II. The Dangers of Wind to Sprinkler Equipment During the entire process of sprinkler irrigation, the water droplets are only released when they’ve already reached a certain height above the ground. As a result, wind becomes highly detrimental to the equipment. Wind forces can disrupt the even distribution of water, leading to inefficient irrigation and potential damage to the machinery.