Precautions for installation and maintenance of irrigation pumps

Precautions for installation and maintenance of irrigation water pumps

I. Precautions for installation

1. Site selection and foundation fixation

Water source location:

The centrifugal pump should be as close to the water source as possible (the suction distance should not exceed 8 meters) to avoid cavitation problems caused by too long suction pipes.

The submersible pump needs to be completely immersed in water (at least 1 meter from the bottom of the well to prevent the inhalation of mud and sand).

Solid foundation:

The thickness of the concrete foundation should be at least 20 cm and fixed with anchor bolts (to prevent vibration and displacement).

Outdoor installation requires a pump room or rainproof shed (to protect the motor from the sun and rain).

2. Pipeline connection

Suction pipe:

The suction pipe of the centrifugal pump should be as short and straight as possible, with a diameter not less than the pump inlet diameter, and a bottom valve should be installed (to prevent water backflow).

Avoid "U" bends or high points (easy to accumulate air and cause idling).

Outlet pipe:

It is recommended to use galvanized steel pipes or PE pipes (with a pressure of at least 1.0 MPa) in high-pressure areas, and add rubber pads at the joints to prevent leakage.

When transporting water over long distances, set an exhaust valve every 500 meters (to prevent air resistance from affecting water flow).

3. Electrical safety

The motor grounding wire must be reliably connected (grounding resistance does not exceed 4 ohms).

Waterproof cables should be used for open-air lines and protected by PVC pipes.

4. Trial operation inspection

Before starting the centrifugal pump for the first time, it must be filled with water and checked whether the direction is correct (reversal will damage the impeller).

Observe whether the pressure gauge is stable. If abnormal vibration or noise occurs, stop the machine immediately for inspection.

2. Daily maintenance points

1. Regular inspection

Bearing lubrication:

Add lithium-based grease every 500 hours of operation (excessive filling will cause heating).

Sealing:

The mechanical seal needs to be replaced when the water leakage exceeds 5 drops per minute (submersible pumps are strictly prohibited from operating in a seal failure state).

2. Anti-blocking and cleaning

Filter:

The filter screen of the sprinkler system should be cleaned once a month (sandy water sources need to be checked weekly).

Impeller:

Disassemble and inspect once a year to remove entanglements or silt (especially for submersible pumps).

3. Seasonal maintenance

Winter antifreeze:

Drain the water in the pipe and loosen the drain screw of the centrifugal pump casing.

Submersible pumps should be placed in storage (to avoid ice and cracking of the pump body).

Moisture-proof in rainy season:

Detect the insulation resistance of the motor winding (not less than 1 megohm, otherwise it needs to be dried).

4. Emergency handling of faults

The pump does not produce water: the possible reasons are leakage in the suction pipe or blockage of the bottom valve. Check the sealing and clean the bottom valve.

Flow rate decrease: the possible reasons are impeller wear or filter blockage. The impeller needs to be replaced (if the gap exceeds 2 mm, it needs to be replaced).

Abnormal vibration: the possible reasons are bearing damage or coupling offset. The bearing needs to be replaced and the concentricity recalibrated.

III. Key measures to extend life

Avoid dry running: the centrifugal pump should not run idly for more than 1 minute, and the submersible pump is strictly prohibited from running without water.

Pressure control: Install a pressure switch or inverter to prevent overpressure (adjustment is required if the rated pressure exceeds 10%).

Water quality management: If the sand content exceeds 5%, a cyclone sand remover needs to be installed (to protect the impeller and seal).

IV. Professional maintenance cycle recommendations

Quarterly: Check the aging of the cable and the tightness of the bolts.

Annually: Entrust the manufacturer to test the insulation performance of the motor and the wear of the hydraulic components.

Tip: A comprehensive overhaul after the end of the irrigation season can reduce the failure rate of the next year by more than 50%.