How to judge whether the composite roller bearing needs to be replaced

Thin oil lubrication: The advantage of roller bearings is that the internal friction coefficient is small, so it consumes less energy to overcome friction, and the thin oil has good fluidity, easy to enter the friction surface of each lubrication point, and has a good cooling effect.

It can also take away the impurities adhering to the friction surface and the metal particles produced by grinding. The disadvantage is that the oil film cannot withstand a large unit pressure and has high requirements for sealing.

High-speed presses generally use large-flow thin oil lubrication, which can take away the heat generated by each friction pair.

The composite roller bearing manufacturer-side roller is installed inside the shaft head through the spindle, the main roller is sleeved outside the shaft head, and the cover plate is fixed by the nut at the end of the shaft head to fix several sides together.

The composite roller bearing shell is divided into adjustable and non-adjustable according to the different structural design.

Adjustable can be divided into gear adjustment, hex adjustment, nut adjustment

The gear adjustment is that both ends of the inner ring of the side roller (that is, the mandrel) are processed into an eccentric gear shape, and the connecting surface of the mandrel and the shaft head is also designed as a gear shape. The whole is adjusted by adjusting the eccentricity of the gear to adjust the protrusion of the side roller The height of the composite roller.

The hexagonal eccentric adjustment is the same principle as the gear adjustment. The tail gear is hexagonal eccentric. The overall height of the composite roller can be adjusted by adjusting the hexagon. Compared with the gear adjustment, the hexagonal adjustable composite roller has higher stability and load strength.

The nut adjustment means that the side rollers are installed on the shaft frame into the shaft head, and the protrusion of the shaft frame (side roller) is adjusted by the two set screws on the head of the shaft head to adjust the overall height of the bearing. Compared with the above two In this way, the nut adjustment is designed without disassembling the bearing, and the adjustment is simple, convenient and quick.

The inner ring (mandrel) of the non-adjustable side roller is cylindrical and connected to the shaft head, which can be rotated. Compared with the adjustable type, this structure is suitable for equipment that does not need to adjust and has stable functions, and the cost is relatively low.

Whether the composite roller bearing can be checked or not is mainly determined by considering the degree of damage to the one-way bearing, mechanical performance, importance, operating conditions, and the period until the next overhaul. If it has the following defects, it can no longer be used, and a new composite roller bearing needs to be replaced. There are cracks or gaps in any one of the inner ring, outer ring, rotating body, and cage.

Most of the bearings are damaged due to many reasons-better than the originally estimated load, ineffective sealing, too small composite roller bearing clearance caused by tight fit, etc. Any of these factors has its own special type of damage and will leave special damage marks. Therefore, by inspecting the damaged bearing, the possible cause can be found in most cases. In general, one-third of one-way bearing damage is caused by fatigue damage, and the other third is caused by fatigue damage. Poor lubrication, the other third is due to contaminants entering the bearing or improper installation and handling.

The so-called burn damage of composite roller bearings refers to the fact that the race wheel, rotating body and cage of the bearing heat up rapidly during torsion until it is discolored, softened, welded and damaged.

The second may be excessive load (excessive preload). The speed is too high. The clearance is too small. Water or other foreign objects have penetrated. If the above two conditions are not hot, it means that the precision of the shaft and the bearing box is poor, and the deflection of the shaft is large. Seeing this, I think everyone wants to know the solution. First of all, we must study lubricants and lubrication methods, choose the right composite roller bearing lubricant, and its amount, and correct the selection of the bearing. Research needs to fit, bearing clearance and preload, and improve the sealing device.

1. Bearing maintenance: In order to maintain the original performance of the bearing in good condition for as long as possible, it is necessary to maintain and overhaul it to prevent any disorder in the first place, to ensure the reliability of operation, and to improve productivity and economy.

Maintain the operating standards of the corresponding mechanical operating conditions and carry out regularly. The content includes monitoring of operating conditions, replenishment or replacement of lubricants, and regular disassembly inspections. Maintenance items during operation include torsion sound, vibration, temperature, lubricant condition, etc. of the one-way bearing.

2. Overhaul of composite roller bearings: cleaning of bearings: When disassembling the bearings for overhaul, first record the appearance of the bearings, confirm the residual amount of lubricant, and wash the bearings after sampling the lubricant for inspection. As a cleaning agent, gasoline and kerosene are commonly used.

The dismantled bearings are cleaned, divided into rough cleaning and fine cleaning. They are placed in the container separately, and a metal mesh is placed on the bottom first, so that the bearing does not directly contact the dirt of the container. During rough cleaning, if the bearing is twisted with dirt, it will damage the rotating surface of the bearing, so care should be taken. In the rough cleaning oil, use a brush to remove grease and adhesions. After it is roughly clean, switch to fine cleaning.

Fine washing is to carefully clean the composite roller bearing while twisting it in the cleaning oil. In addition, the cleaning oil should always be kept clean.

3. Inspection and verification of composite roller bearings: In order to verify whether the disassembled bearings can be used, they must be checked after the composite roller bearings are cleaned. Check the condition of the raceway surface, the rotating surface, the mating surface, the wear of the cage, the increase of the one-way bearing clearance, and the damage that has nothing to do with the decrease of dimensional accuracy. For non-separable small ball bearings, use one hand to support the inner ring horizontally, and twist the outer ring to confirm whether it is smooth.