Pump Industry

Special bearings for pumps and compressors

For screw compressors used in chemical environments such as compressor oil, refrigerating machine oil, and ammonia refrigerant, the bearings used must also have chemical stability such as high oil resistance and heat resistance. NSK uses "L-PPS resin cage" with good chemical stability in special bearings for screw compressors. This cage is not affected by the environment and can give full play to high performance.

High load capacity angular contact ball bearings

This is a special ball bearing for high load capacity screw compressors using "L-PPS resin cage" with good chemical stability.

Features:

1. Adopt "L-PPS resin cage" which has heat resistance and hardly loses strength in compressor oil, refrigerator oil, ammonia refrigerant, etc.

2. Increased load capacity through internal design optimization.

3. Increased ultimate axial load through internal design optimization.

4. The lubricating performance is improved by adopting the rolling element guide cage.

High Load Capacity Cylindrical Roller Bearings

This is a special roller bearing for high load capacity screw compressors using "L-PPS resin cage" with good chemical stability.

Features:

1. Adopt "L-PPS resin cage" which has heat resistance and hardly loses strength in compressor oil, refrigerator oil, ammonia refrigerant, etc.

2. Increased load capacity through internal design optimization.

3. The lubricating performance is improved by adopting the rolling element guide cage.

Maintenance methods of pump bearings and precautions when disassembling and assembling:

1. The newly put into use of the water pump, generally need to replace the grease (oil) after 100 hours of operation, and once every 500 hours of operation thereafter.

2. The flow bearing lubricated with grease should be replaced after 1500 hours of operation. The amount of oil added should not be too much or too little, because too much or too little grease will cause the bearing to heat up. The amount of oil is generally controlled at 1/2 to 2/3 of the bearing chamber volume is appropriate.

3. For bearings lubricated with lubricating oil, the amount of oil should be added to the specified position.

4. The container for lubricating oil or grease should be clean, usually sealed well, and there should be no dust, iron filings and other debris, so as not to damage the bearing.

5. Sodium-based grease is generally used for motor bearings. This grease is characterized by high temperature resistance (125 ° C), but is easily soluble in water, so it cannot be used for the lubrication of water pump bearings.

What should be paid attention to in the disassembly and assembly of bearings in gear pumps

The following are the issues to pay attention to when disassembling and assembling bearings:

(1) The drag force should continue to the proper extent. For example, when installing the bearing, the screw pump should stop applying force when the bearing is just installed in the correct position to ensure that the end face of the ring (washer) abuts the seat hole or the shoulder of the shaft. The end face can neither be squeezed too tightly nor can it be installed out of place.

(2) The resultant force of the force should pass through the axis of the oil-free bearing as much as possible. This requires the force application point to be uniform, symmetrical and stable, and the force should be applied through the spherical surface or parallel to the axis.

(3) Avoid applying force through the rolling elements. The diaphragm pump requires applying force through the inner ring when installing and removing the inner ring (shaft ring), and applying force through the outer ring when installing and removing the outer ring.

(4) The magnitude of the force should be stable and even, and there should be no impact. Self-priming pumps require the use of oil pressure or tools that can apply stable tension or pressure. Softer, non-chipping metal is cushioned, and the percussion force is as gentle as possible. Hammering is best done with a copper rod or hammer.