Asphalt insulated pumps are commonly used in asphalt mixing plants for infrastructure projects such as highways, municipal roads, airports, and ports. Correct operation and adjustment are essential for maintaining performance and service life.
1. Pre-Start Checks
Before starting the pump:
- Rotate the pump shaft manually to check whether the gears move freely.
- Ensure the motor’s rotation direction matches the pump’s specified direction.
- Open the inlet valve and close the discharge valve and pressure gauge cock.
- Fill the pump completely with fluid or purge air from the inlet line and pump body.
- Inspect and tighten all coupling bolts between the pump and motor.
- Make sure the surrounding environment is safe and clean for operation.
2. Starting the Pump
- Start the motor and let the pump run normally.
- Open the pressure gauge cock and slowly open the outlet valve.
- Monitor the pressure gauge until it reaches the desired operating pressure.
3. Balancing Mechanism
Asphalt insulated pumps use an internal balancing mechanism to counter axial thrust.
The balancing liquid exits through a balancing oil pipe and either:
- Returns to the inlet section, or
- Is discharged outside the pump through a short external pipe.
⚠️ The balancing oil pipe must not be blocked, or it may affect pump operation.
4. Operational Monitoring
During operation, observe the following:
- Instrument readings and pressure values.
- Bearing temperature.
- Seal (packing) leakage and temperature.
- Vibration and operational noise of the pump.
🔧 If any abnormal behavior is detected, stop the pump and address the issue immediately.