1. Maintenance and monitoring of rolling mill bearings Bearings
should be maintained and monitored during use to extend their service life.
1. Keep the lubricating oil path unobstructed, select the type of lubricant according to regulations, and add sufficient lubricant regularly. Ensure that the rolling surface of the roller and the sliding surface of the roller and the rib are well lubricated by oil and wax.
2. Regularly check the sealing condition of the seals and replace damaged seals in time. Ensure the sealing performance of the bearing to prevent water and iron oxide scale from entering the bearing and prevent the leakage of bearing lubricant.
3. Based on the actual situation of the enterprise, actively carry out monitoring of bearing operating conditions.
Noise monitoring: There should be a steady hum during normal operation. Regularly monitor and compare with the normal sound to detect abnormalities in time.
Lubricant monitoring: Normal lubricant should be clear and clean. If the lubricant becomes dirty, there will be wear particles or contaminants.
Temperature monitoring: When the temperature rises, abnormal operation will occur. The company has carried out temperature monitoring work and is willing to serve customers more extensively.
2. Lubrication of rolling mill bearings
1. The importance of lubrication
The lubrication of bearings uses oil films to separate relatively moving rolling surfaces from each other so as to prevent excessive wear and failure due to rough point contact. If users attach great importance to bearing lubrication technology, {TodayHot} can ensure that stable performance and rotation accuracy can be maintained during the predetermined working life.
2. Types and performance of grease.
The lubrication of rolling mill bearings is divided into grease lubrication and oil lubrication. The advantages of grease lubrication are simple lubrication facilities, grease is not easy to leak, and it has a certain ability of waterproofing, gas and other impurities to enter the bearing, so it is generally Grease lubrication is widely used in this case. Use oil for lubrication under heavy load, high speed, high temperature and other working conditions.
Grease is composed of base oil, thickener and additives. The viscosity of the base oil plays an important role in the lubrication performance of the grease. The composition of the thickener has an important impact on the performance of the grease, especially the temperature characteristics, water resistance, and oil separation properties. Additives are mainly used to enhance the resistance of the grease. Gasification, anti-rust, extreme pressure and other properties.
Greases are classified according to different types of thickeners, including lithium-based, nano-based, and other types. Lithium-based grease is commonly used in rolling mill bearings. Lithium-based grease is characterized by good water resistance and high dropping point. {HotTag} can be used in mechanical parts that are wet and in contact with water. Grease is divided into several grades according to its fluidity, that is, penetration. The higher the penetration value, the softer the grease.
The performance of commonly used lithium-based greases is shown in the following table.
3. Grease filling amount
. The filling amount of grease should fill one-third and one-half of the space of the bearing and bearing shell. If there is too much grease, As the heat is removed by stirring, the fat will deteriorate or become liquefied. On high speed it should only be filled to a third or less. When the rotation speed is very low, in order to prevent external foreign physics from entering the bearing, the housing space can be filled up.
4. Grease replacement:
The service life of grease is limited, its lubrication performance gradually decreases during use, and wear gradually increases, so it must be replenished and replaced at certain intervals.
The grease replenishment cycle is related to the bearing structure, rotation speed, temperature and environment, and should be determined according to the specific working conditions of the enterprise. When replacing grease, please note that greases of different brands cannot be mixed. Mixing greases containing different types of thickeners will destroy the structure and consistency of the lubrication. If it is necessary to replace greases with different brands, the original ones in the bearing should be removed. After the grease is completely removed, add new grease.
3. Storage and storage of rolling mill bearings
Bearings are precision mechanical components and have strict requirements for their storage and storage.
(1) Warehouse temperature: Bearings are coated with anti-rust oil before leaving the factory. If the temperature is too low or too high, the anti-rust oil will deteriorate. The room temperature should be controlled at 0-25°C.
(2) Warehouse humidity: Excessive humidity will cause bearings to rust. The relative humidity of the warehouse should be maintained at 45%-60%.
(3) Warehouse environment: Bearings are best stored separately. When they must be stored together with other items, the other items stored together must not be chemicals such as acids, alkalis, and salts.
Bearings should be placed off the ground and away from heating pipes.
(4) Regular inspection: According to the regulations on anti-rust of bearing products, regular inspection should be carried out every 10-12 months. If the oil seal packaging is found to be rusty, the oil seal packaging should be repackaged.
