Causes of Bearing Damage and Repair Methods

Time：2020.08.21  Source：Roller Bearings Suppliers

Due to the quality and external conditions of the rolling bearing during use, its load-carrying capacity, rotation accuracy and anti-friction performance will change. When the performance index of the bearing is lower than the use requirement and cannot work normally, it is called bearing damage Or failure, once the bearing is damaged or other accidents, there will be various abnormal phenomena such as machine and equipment stalling and function damage.

If the bearing is broken, we must first analyze the cause of the failure, and then find a solution. Therefore, it is necessary to investigate and deal with the causes in a short period of time and take corresponding measures.

Bearings are wearable parts. As long as they are used, they will definitely be damaged. It only shows up after a certain amount of accumulation. Of course, the damage of rolling bearings is more complicated than that of ordinary mechanical parts. The characteristics of rolling bearing damage are many manifestations and complex reasons. In addition to the internal factors of bearing design and manufacturing, most of the damage of the bearing is due to improper use, such as: inappropriate selection; unreasonable support and design; improper installation ; Poor lubrication; poor sealing and other external factors. Need WSBC NJ315EM, pls click here learn more :

1. Metal corrosion occurs

If there is a lack of lubrication, it is easy to be oxidized by air and rust. To prevent the corrosion of the bearing, do not soak with water. The bearings are made of stainless steel, but they are also afraid of water. When picking up the bearing by hand, thoroughly wash off the sweat from your hands and apply high-quality mineral oil before operating. Pay special attention to rust prevention during the rainy season and summer.

The specific causes of natural bearing corrosion and wear are mainly as follows:

(1) Oxidative wear

The tiny peaks and valleys on the friction surface squeeze each other, causing the brittle surface layer to gradually fall off and wear. The tiny peaks and valleys on the surface of the bearing's relative motion are combined with the oxidation in the air to form brittle oxides that are not firmly bonded to the base metal. The oxides are very easy to fall off during friction. The wear that occurs is called oxidative wear.

(2) Friction, heat and wear

When the bearing works under high speed, heavy load and poor lubrication, high temperature is generated at the peaks and valleys of the surface due to friction, the hardness and wear resistance of the contact points decrease, and even adhesion and tearing occur. This kind of wear is called friction heat wear.

(3) Hard particle wear

If the bearing makes relative movement. The surface of the bearing is uneven in structure, there are hard particles, or impurities such as sand, friction, and cutting chips fall into the surface of the bearing. During the relative movement of the bearing, the hard particles or impurities will scratch the surface of the bearing and even form grooves. This kind of wear is called hard particle wear.

(4) Pitting corrosion

Gears, bearings, etc. are in rolling contact with the surface. During the relative process, they are periodically subjected to large contact pressures. After long-term action, fatigue occurs on the metal surface, causing micro cracks and erosion on the bearing surface. This wear is called pitting wear.

(5) Cause rust or corrosion, wear caused by chemical corrosion

The bearing surface is corroded by acid, alkali, salt liquid or harmful gas. Speeds up the wear process, which is called wear caused by chemical corrosion.

Due to temporary contact with water, acid, alkali, salt and other liquids or harmful gases, corrosion damage: non-moving bearings on the equipment. Damage caused by rust or corrosion is called corrosion damage.

2. The bearing is overloaded or used improperly

When in use, the load of the bearing should not be exceeded. Like a car, the load may be too heavy, and the bearing may be easily damaged. Therefore, trucks have more problems than cars, which are caused by the failure of many parts. WSBC NJ316EM roller bearings online, pls click here :

3. Poor installation

To install the bearing, follow the installation steps of the bearing, do not install and dismantle brutally. Whether the bearing is installed correctly or not is related to the service life of the bearing, so everyone must pay attention to it. When installing the bearing, avoid holding it directly with your hands, because sweat on your hands may also cause rust. Don't ignore the small links. When installing the bearing, the most important thing is not to allow strong punching and direct hitting of the bearing with a hammer, not for fear of smashing it, but for fear of smashing and deforming. The deformed bearing will become unusable. There is also no pressure to pass through the rolling elements.

4. Foreign body intrusion

Try to use special tools, and try to avoid using cloth and short fibers, so as to prevent fine fibers from entering the bearing and causing unnecessary damage. For another example, when installing the bearing, the staff used the copper rod knock-in method, which easily caused uneven axial force on the bearing, causing deformation of the cage, damage to the rolling elements, and larger clearance, and the copper rod was knocked in the process. The copper powder flies into the bearing cage, which can easily cause bearing failure.

5. Too much oil in the bearing and box

Excessive amount of oil in the bearing and the box will cause the rolling elements of the bearing to slip, causing the rolling friction to change from rolling friction to sliding friction, which will damage the bearing rolling elements. Due to the excessive amount of bearing oil, the free space in the bearing box is small, and the operating temperature of the bearing will rise , The lubricating grease density is reduced, the rolling element lubricating oil film becomes thin, the lubrication condition is poor, it is easy to cause abnormal bearing noise, surface slippage, and shorten bearing life.

6. For bearings with an insulation design on the outer ring, ensure good insulation

If the bearing insulation is damaged during installation, the very thin bearing oil film will be broken down by the shaft voltage. After the oil film breaks down, not only will the lubrication conditions of the rolling elements be poor, but also the electric sparks generated will form electrical corrosion on the bearing rolling elements, causing the rolling elements The surface is not polished, which accelerates the wear of the bearing.

Wear of the bearing can be repaired in this way. The solution is to re-study the operating conditions or re-select the bearing, observe the clearance and check the machining precision between the shaft and the bearing bar, check the design around the bearing, study and check the installation method and the lubricant and lubrication method.

It is of great significance to study the formation and causes of rolling bearing damage. On the one hand, it can improve the use method, use the bearing correctly, and give full play to the performance of the bearing. On the other hand, it can help to develop new products with better performance. In addition to describing the precautions, installation methods, and operation supervision of rolling bearings, this article also focuses on the forms and causes of bearing damage and the countermeasures to be taken. The life of the bearing has a certain number of years. If we use it properly and pay attention to the above use matters normally, the bearing will fully play its role.