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In the process of using NSK Bearings, grease is very critical. If deteriorated grease is used, it will Check Whether not only fail to play its due role, but also damage NSK Bearings.
1. Illumination method
On sunny days, lift up NSK bearing lubricating oil with a screwdriver at an angle of 45 degrees to the horizontal plane. Observe the condition of oil drops according to the sunlight.
Under the sunlight, it can be Check Whether clearly seen that there is no wear debris in the bearing lubricating oil. It can continue to function. If there are too many wear debris, replace the lubricating oil.
2. Oil drop trace method
Take a clean white filter paper and drop several drops of oil on the filter paper. After the lubricating oil leaks, if there is black powder on the surface and there is a sense of astringency by hand,
it indicates that there are many impurities in the lubricating oil. Good lubricating oil has no Check Whether powder, and it is dry and smooth by hand and shows yellow traces.
3. Oil flow observation method
Take two measuring cups, one of which is filled with NSK bearing lubricating oil to be checked, and the other is empty on the table. Lift the measuring cup filled with lubricating oil 30-40 cm away from the table and tilt it. Let NSK bearing lubricating oil flow slowly into the empty cup and observe its flow.
The lubricating oil with good quality should flow slender, Check Whether uniform and continuous. If the oil flow is fast and slow, Sometimes a large piece of oil flows down, which means that the lubricating oil has deteriorated.
Twist NSK bearing lubricating oil between thumb and index finger Check Whether and grind it repeatedly. The better lubricating oil hand feels lubricity, less wear debris and no friction.
If it feels a large friction feeling such as sand particles between fingers, it indicates that there are many impurities in the lubricating oil and it can not be used again. It should be replaced with a new lubricating oil.
（1） The role of NSK bearing lubrication lubrication has an Check Whether important impact on the fatigue life, friction, wear, temperature rise and vibration of rolling bearings. Without normal lubrication, NSK Bearings cannot work.
The analysis of the causes of bearing damage shows that about 40% of bearing damage is related to poor lubrication. Therefore, good bearing lubrication is an effective measure to reduce the friction and wear of NSK Bearings.
（2） Comparison of grease lubrication and oil lubrication the lubrication methods of NSK Bearings are roughly divided into grease lubrication and oil Check Whether lubrication. In order to give full play to the function of NSK bearing, it is important to adopt lubrication method according to the use adjustment and purpose.
（3） Grease is a lubricant composed of base oil, thickener and additives. When selecting, the lubricating grease that is very suitable for the service conditions of NSK Bearings should be Check Whether selected. Due to different trademarks, there will be great differences in performance, so we must pay attention to it when selecting.
（4） When selecting grease according to the working temperature, the main indicators should be the drop point, oxidation stability and low-temperature performance. The drop point can generally be used to evaluate the high-temperature performance.
The actual working temperature of NSK bearing should be 10-20 ℃ lower than the drop point. The Check Whether service temperature of synthetic grease shall be 20-30 ℃ lower than the dropping point.
（5） Oil lubrication under the condition of high speed and high temperature, oil lubrication can be used when grease lubrication is no longer suitable. Through the circulation of lubricating oil, a lot of heat can be taken away.
Viscosity is an important characteristic of lubricating oil. The viscosity directly affects the fluidity of lubricating oil and the thickness of oil film formed between friction surfaces. The viscosity of lubricating oil at the working temperature of NSK bearing is generally 12-15cst.
（6） Solid lubrication under some special service conditions, add a small amount of solid lubricant to the grease. For example, adding 3 ~ 5% molybdenum disulfide 1 can reduce wear and improve the compression and heat resistance.
For special conditions such as high temperature, elegance, high vacuum, corrosion resistance, radiation resistance and very low temperature, add solid lubricant to engineering plastics or powder metallurgy materials, NSK bearing parts with self-lubricating performance can be made.
For example, solid lubricant is bonded to raceway, cage and rolling body with adhesive to form lubricating film, which has a certain effect on reducing friction and wear.
（7） Replenishment and replacement of lubricant A. replenishment interval of lubricating grease due to mechanical action, aging and increased pollution, the lubricating base filled in NSK bearing configuration will gradually lose its lubricating performance.
Therefore, the lubrication rank needs to be continuously supplemented and updated. The interval of lubricant replenishment varies with the formation, size and speed of NSK bearing. The approximate interval of grease replenishment is required according to the operation time.