Several problems should be paid attention to when the bearing is damaged by vibration

Generation of vibration in bearings Generally speaking, rolling bearings do not generate noise. The "bearing noise" usually felt is actually the sound effect of the bearing directly or indirectly vibrating with the surrounding structure. That's why many times the noise problem can be considered as a vibration problem involving the entire bearing application.

(1) Excitation due to changes in the number of loaded rolling elements: When a radial load is applied to a bearing, the number of rolling elements that carry the load will change slightly during operation, which causes the load direction to shift . The resulting vibration is unavoidable, but can be mitigated by axial preloading, which is applied to all rolling elements (not applicable to cylindrical roller bearings).

(2) Local damage: Due to operation or installation errors, a small number of bearing raceways and rolling elements may be damaged. During operation, rolling through damaged bearing components generates specific vibration frequencies. Vibration frequency analysis can identify damaged bearing components. This principle has been applied to condition monitoring equipment to detect bearing damage. To calculate the bearing frequency, refer to the calculation procedure "Bearing Frequency".

(3) Accuracy of related parts: In the case of close fit between the bearing ring and the bearing housing or the drive shaft, the bearing ring may be deformed in accordance with the shape of the adjacent parts. If deformation occurs, vibration may occur during operation.

(4) Contaminants: If operating in a polluted environment, impurities may enter the bearings and be crushed by the rolling elements. The degree of vibration generated depends on the number, size, and composition of the foreign particles being crushed. Although it does not produce a typical frequency form, it can be heard as a disturbing noise.

The causes of noise produced by rolling bearings are more complicated. One is the wear of the matching surfaces of the bearing's inner and outer rings. Due to this wear, the cooperation relationship between the bearing and the housing, and the bearing and the shaft is destroyed, causing the axis to deviate from the correct position, and an abnormal noise is generated when the shaft moves at high speed. When the bearing is fatigued, the surface metal peels off, which will also increase the radial clearance of the bearing and produce abnormal noise. In addition, insufficient lubrication of the bearings, the formation of dry friction, and broken bearings will produce abnormal sounds. After the bearings are worn and loose, the cage will be loose and damaged, and abnormal noise will also occur.

In daily use of bearings, we need to pay careful attention to its use. Let us take a look at the nine major issues that we need to pay attention to.

1. The riveting parts in the harvester, such as the moving knife assembly, are generally made by cold extrusion. They should not be heated during riveting. If heated, the material strength will be reduced. After riveting, a punch and a heavy willow are applied to strengthen the firmness of the blade and the arbor.

2. Vulnerable parts, especially pins, tablets, sleeves, and horns, cannot be replaced with more butter for replacement and repair during maintenance. If worn parts are used for a long time, the life of other machinery will be shortened.

3. Shaft repair without balancer. When balancing various shafts, you can install a thrust bearing on one end of the shaft and clamp it on the three claws of the lathe. The other end can be pointed, if the lathe is short, the center frame can be used. Clamp the SKF bearing mounted on the shaft at the other end until the balance is corrected. However, when counterweighting, tighten with screws, try not to use electric welding to counterweight.

4. Due to the variety of bearing material types during maintenance, it is not easy to purchase and can be used to process used shafts. At present, most of China's shafts are mainly 45 # carbon steel. If quenching and tempering are required, it can be used under poor conditions. Oxygen, earth furnace will heat the required parts into the red Zhongfawu place in the brine, according to demand.

5. It is very difficult to pull the oil groove in the sleeve hole when processing sleeve parts. Because some parts of the harvester are very difficult to refuel, butter and heavy machine oil can be used in difficult places, except for nylon sleeves. Where the nylon sleeve is used, do not replace it with cast iron, copper, or aluminum, because the nylon sleeve will withstand a certain impact without deformation.

6. The repair of the key and keyway on the pulley and the shaft should ensure that the size does not change in advance. Do not increase the size of the key, otherwise the strength of the shaft will be affected. The keyway on the shaft can be repaired with electric welding filler in the opposite direction of the old key. One key slot, the key slot on the belt wheel can be set (transition fit), after setting, use countersunk screws to tap and insert the key in the slot.

7. Maintenance of the hydraulic part of the harvester. Remove the distributor and flow reducing valve, etc., and use a gas pump to pump the pressure of each pipe. The hydraulic oil should be filtered and vented when it is reloaded. The maintenance of the assembly hydraulic pressure is mainly the seals. Seals should be removed and replaced with new ones.