Using the previous "three inspections"

Inspect all parts of the equipment to ensure that all bolts are present and securely tightened, guaranteeing the safe operation of the water pump.

When checking whether a diesel engine is being used safely and effectively, ensure that cooling water, lubricating oil, and other essential fluids are present and that the engine is running smoothly. For electric motors, carefully inspect the wiring setup and connections to confirm they meet safety standards, verify that the grounding wire is secure, check for any moisture damage to the motor, and ensure the electrical circuits remain intact—this will help prevent electric shock hazards and guarantee safe electricity usage.

Ensure that the unit power ratings are compatible and that all installations are securely fastened. Pay close attention to verify whether the transmission connection between the prime mover and the pump is properly aligned, safe, and reliable. Also, confirm that safety protection devices—such as guard plates or protective nets—are installed at the transmission connection points to prevent potential hazards or accidents.

Use the "Three Essentials" approach

The installation of the vibration-free pump unit must be precise and secure—there should be no noticeable vibrations during operation. If the pump produces unusual noises while running, or if the bearings feel excessively hot (temperature exceeding 60°C), or if water leaks from the pump shaft seal at a rate greater than 60 drops per minute, it’s crucial to identify the root cause and address the issue promptly. For regularly tightened screws—such as those on the packing gland cover or the water inlet plug—use the appropriate wrench with proper torque for assembly and disassembly. Avoid using pliers, as this could damage the threads or strip the nuts. For other screws, apply a thin layer of lubricant or periodically wipe them down with an oiled cloth to prevent rusting. Finally, pay special attention to drain screws, which tend to seize up over time due to infrequent use. Before tightening or loosening these screws, first remove the drain plug entirely. Then, coat the threaded area generously with a mixture of machine oil and white lead grease. Afterward, reapply fresh oil 2–3 times per year to keep the mechanism functioning smoothly.

For scientifically lubricated pumps using oil-based lubricants, change the lubricant monthly; for those lubricated with grease, replace it every six months. Note that calcium-based grease should be used for the pump, while sodium-based grease is suitable for the motor—never mix them up. Sodium-based grease is hydrophilic, meaning it attracts water; if exposed to moisture in the pump, it’ll emulsify into a foamy substance that eventually dissipates. On the other hand, calcium-based grease is sensitive to high temperatures and can easily break down when used in motors under heat.

Avoid idling, do not pump sand, and refrain from drawing water with excessively high sand content to prevent premature wear of components like the impeller, wear rings, and shaft. Additionally, take proactive measures to prevent operation under low-water conditions, as running dry can damage the mechanical seal, leading to leaks—or even complete failure to deliver water altogether. After the irrigation and drainage season ends, promptly and thoroughly clean and inspect the pump. If any parts are found damaged or deformed and no longer suitable for use, repair or replace them immediately to ensure optimal performance.