How to Adjust Impeller Pressure by Slurry Pump

Adjust the clearance between the impeller and the guard plate

Metal lining pump

Stop the pump operation: First stop the slurry pump from running to ensure that the adjustment operation is carried out in a safe state.

Loosen bolts: Loosen the bolts that tighten the bearing assembly.

Forwardly moving bearing assembly: Tighten the nut on the adjustment bolt to move the bearing assembly forward, while rotating the shaft with your hands in the transmission direction of the slurry pump until the impeller rubs against the front guard plate.

Determine the clearance: Relax the newly tightened nut for half a turn, then tighten the nut on the front of the adjustment bolt to move the bearing assembly backward. At this time, the gap between the impeller and the front guard should be between 0.5-1mm.

Rubber lining pump

Stop the pump and loosen the bolts: First stop the pump, then loosen the bolts that tighten the bearing assembly and the bearing assembly adjustment bolts on the bracket.

Measure the movement distance: By twisting the nut on the adjustment bolt, the bearing assembly is moved forward first to the contact between the impeller and the front sheath, and then the bearing assembly is moved backward to the contact between the impeller and the rear sheath, and the total movement distance of the bearing assembly is measured.

Determine the installation clearance: Take half of the total moving distance as the gap between the impeller and the front and rear sheath, and then adjust the position of the bearing assembly by adjusting the bolts to ensure the correct gap between the impeller and the front and rear sheath.

Change the impeller speed

According to the pump's similarity law, with the impeller diameter unchanged, the pump's head (dependent on pressure) is proportional to the square of the rotation speed. The speed can be changed in the following ways:

Using the frequency converter: If the motor equipped with the slurry pump is connected to the frequency converter, the motor speed can be changed by adjusting the output frequency of the frequency converter, thereby adjusting the impeller speed and achieving the purpose of adjusting the pressure. For example, in some operating conditions where pressure requirements vary greatly, the motor frequency is reduced from 50Hz to 40Hz through the inverter, and the rotation speed is reduced, and the pressure generated by the impeller will also be reduced accordingly.

Replacement of transmission pulleys or gears: For slurry pumps that use belt drives or gear drives, the transmission ratio can be changed by replacing pulleys or gears of different diameters, and thus the rotation speed of the impeller. For example, increasing the diameter of the active pulley or reducing the diameter of the driven pulley will increase the impeller speed and increase the pressure.

Replace impellers of different specifications

Change the impeller diameter: The size of the impeller diameter has a direct impact on the pressure of the pump. Within the allowable range, replacing the impeller with a larger diameter will usually increase the pressure; conversely, replacing the impeller with a smaller diameter will reduce the pressure. However, when replacing the impeller, it is necessary to consider whether the other parts of the pump can be matched and whether the motor power is sufficient.

Change the blade angle of the impeller: The impeller with different blade angles has different functional power on the liquid, which affects the pressure. For example, if the angle of the impeller blade is appropriately increased, the energy obtained by the liquid in the impeller increases, and the pressure at the pump outlet will be increased accordingly. However, this method usually requires professional design and manufacturing, and is generally used when modifying or customizing the slurry pump.

Adjust the opening of the outlet valve

By adjusting the valve opening on the outlet pipe of the slurry pump, the resistance characteristics of the pipeline system can be changed, thereby indirectly affecting the impeller pressure. When the small outlet valve is closed, the pipeline resistance increases, the pump discharge pressure will increase, but the flow rate will decrease; when the large outlet valve is opened, the pipeline resistance will decrease, the exhaust pressure will decrease, and the flow rate will increase. However, this method will increase the energy loss of the pipeline system and is generally suitable for small-scale fine-tuning of pressure and flow.