In-depth Demand Report | Disassembling Corrosion Resistant Impeller

1. Features of high chrome alloy impellers and their application

1. Abrasion-resistance: With very high hardness, high chrome alloy can effectively resist the abrasion of solid particles, making sure that the impeller can keep good performance during operation;
2. Corrosion-resistance: high chrome alloy is able to resistant the corrosion of many chemicals, including acid, alkaline and other high corrosive medium, making sure that the impeller will work steadily under harsh applications;
3. High efficiency and energy saving: High chrome alloy impeller has a unique design, compact structure, and works with steadiness, which will help decrease energy consumption, thus increasing the operating efficiency of the slurry pumps.

High chrome alloy impellers are widely used in mining, metallurgy, power plants and so on for the slurring transporting system. When used on mine sites, high chrome alloy impellers are used to pump slurry containing high concentration of solids; and when used for metallurgy, they will be used to handle tailings which contain high hardness, high corrosion slurries.

2. Features of rubber coated impellers and their application

1. Abrasion-resistance: rubber material has rather good abrasion resistance, and will help reduce the impeller abrasion from solid particles, so that the impeller working life will be prolonged;
2. Corrosion-resistance: Rubber impeller is able to fight the erosion from weak acidic medium, making sure the stable operation of the impeller under generally corrosive applications;
3. Lower noise and vibration: Rubber has a good flexibility, and will effectively lower the noise and vibration generated during the pumping process, therefore changing the working environment.

Rubber impellers are widely used in coal, power plants and environmental protection industries. For instance, in coal industries, customers will use rubber impeller to transfer coal mud, gravel etc., and when used in environmental protection, rubber impellers are adopted to handle waste water that contains corrosive (acidic or alkaline) medium.

3. Difference of High chrome alloy impellers and Rubber impellers when used for slurry pumps

1. Abrasion: High chrome alloy impellers have very high abrasion resistance, and has obvious advantages for pumping high density, high hardness sludge. Whereas, although rubber impellers can also resist abrasion, compared with high chrome alloy, rubber impellers are inferior;
2. Corrosion: High chrome alloy can resistant the corrosion of many different chemicals, including strong acid and strong alkali, but rubber impellers are more suitable for weak acidic medium transfer;
3. Applications: High chrome alloy impellers are more used for mining, metallurgy where high density, high hardness, and high corrosive slurry needs to be pumped; and rubber impellers are more used for coal, power plants, and environmental protection industries where low concentration, low hardness and weak corrosive medium needs to be transported;

High chrome alloy and rubber impellers have its own features when used in slurry pumps. When selecting the impeller material, it should be determined according to the specific working conditions and the characteristics of the conveying medium to ensure the stable operation and efficient performance of the slurry pump.

Situation (A) 

After the impeller or the guard plate is worn: 

During the operation of the slurry pump, the impeller and the guard plate will cause the clearance to increase due to media scouring and abrasion. When the clearance exceeds the permissible range of the equipment, it is necessary to restore the standard clearance by adjusting the position of the impeller to ensure stable performance of the pump.

When the flow rate or discharge head drops :

If the flow rate or discharge head of the pump is lower than the design value, the impeller clearance may be too large, resulting in media backflow or leakage. At this time, it is necessary to check and adjust the clearance to restore the pump's transporting capacity.

Situation (B)

When efficiency decreases or energy consumption increases :

When the impeller clearance is too large, the volume loss and mechanical loss of the pump will increase significantly, resulting in a decrease in efficiency and an increase in energy consumption. By adjusting the clearance, the leakage can be reduced and the operating efficiency of the pump can be improved.

When vibration or noise is abnormal :

Excessive clearance between the impeller and the guard plate may lead to increased vibration of the pump casing or abnormal noise. Adjusting the clearance can improve the fit between the rotor and stator and reduce the operating noise and vibration.

Situation (C)

After replacing the impeller or guard plate:

The dimensions of the new pump part may differ from the original part, and the impeller clearance needs to be readjusted to ensure that it meets the technical requirements of the equipment.

During regular maintenance inspection:

According to the equipment maintenance program, the impeller clearance needs to be checked regularly. If the clearance is found to be out of the standard range, it should be adjusted in time to prevent performance degradation or failure occurrence.

1.Before adjustment, you need to stop and cut off the power supply to ensure safe operation.

2.After adjustment need to check whether the impeller rotation is flexible, no jamming phenomenon.

3.It need to restart the pump and monitor the operating parameters, confirm the performance recovery after the completion of the adjustment.

4.Through timely adjustment of impeller clearance, can effectively extend the service life of slurry pump, reduce operating costs, and ensure its efficient and stable operation.