DESMI Rotan asphalt pump troubleshooting and troubleshooting

Asphalt pumps are suitable for conveying media with a temperature of 350°C, a viscosity of no 

more than 200mm2/s, and various types of asphalt and paraffin that do not contain solid particles, 

which are solidifiable at room temperature, and where heat preservation is required during outdoor

 installation and process in alpine areas.

1. The asphalt pump does not produce oil

1. The inlet and outlet valves are not opened, the inlet and outlet pipes are blocked, and the flow impeller

 is blocked; check and remove the blockage.

2. The motor movement direction is wrong, the motor phase is missing, and the rotation speed is very slow; 

adjust the motor direction and tighten the motor wiring.

3. The suction pipe is leaking; tighten each sealing surface to remove the air.

4. The pump is not filled with liquid and there is air in the pump cavity; open the upper cover of the pump or 

open the exhaust valve to drain out the air.

5. The inlet oil supply of the gear lubricating oil pump is insufficient, the suction stroke is too high, and the bottom 

valve leaks oil; stop inspection and adjustment.

6. The pipeline resistance is too large and the pump selection is inappropriate; reduce the pipeline bends and select a new pump.

2. Insufficient outlet pressure of asphalt pump

1. There is air in the liquid; there is air in the liquid.

2. The speed is too low and the impeller is damaged; increase the pump speed and replace the impeller.

3. The outlet valve opening is too large; adjust the outlet valve smaller.

3. Insufficient flow of Rotan asphalt pump

1. The impeller of the heat preservation pump flow channel is partially blocked, oil deposits are deposited, 

and the valve opening is insufficient; remove the blockage and readjust the valve opening, pump and pipeline.

2. The revolution is too low; increase the revolution of the oil pump shaft.

3. The impeller is worn; replace the impeller.

4. The outlet valve opening is too large; replace the impeller.

5. The voltage is low; stabilize the voltage.

4. Asphalt pump motor heats up

1. The ambient temperature is too high and the motor has poor heat dissipation.

2. The motor load is too heavy.

3. The voltage is too high or too low or the phase is missing. 

4. Oil is fed into the motor; check the mechanical part and adjust it in time. The positive outlet valve 

of the booster fuel pump regulator makes the pump work near the rated flow and lift.

5. Asphalt pump oil leakage

1. The mechanical seal is worn; replace it.

2. The pump body has sand holes or cracks; weld or replace.

3. The sealing surface is uneven; trim it.

4. The installation bolts are loose; tighten them.

6. Asphalt pump vibrates or makes noise

1. The installation of the unit is not firm; the supporting parts at the pump flange should be reinforced.

2. The oil suction pipe leaks or the suction pipe mouth is not submerged deep enough, causing air to be sucked

 into the pump; block the air leakage or lengthen the submersion depth of the suction pipe.

3. Cavitation occurs in the impeller; YCB arc gear pump should reduce the installation height of the pump or

 increase the suction pipe diameter or increase the inlet pressure, and replace the damaged impeller.

4. Deviate from the operating conditions; adjust to the high-efficiency zone (rated point) as much as possible 

to avoid running the pump at a large flow point.

7. Asphalt pump power is too large

1. Use when the rated flow rate is exceeded; adjust the flow rate and close the outlet valve.

2. The suction lift is too high; lower the installation surface.

3. If there is a power outage or the heating medium circulation is interrupted for more than 30 minutes, the asphalt 

pump should be disassembled, cleaned and reassembled to avoid damage to the pump due to poor bearing lubrication 

due to melt solidification, cracking, etc.