General conditions of stable rotation friction coefficient reference value shown sliding bearings in general 0.010.020.10.2 various types of bearing friction coefficient bearing type friction coefficient. In order to facilitate comparison with sliding bearings, rolling bearing friction moment can be calculated by the following formula according to the bearing inner diameter. M = uPd / 2 (M: friction torque, mN.m; u: friction coefficient, Table 1; P: bearing load, N; d: bearing nominal inner diameter, mm). Friction coefficient u is affected by bearing type, bearing load, speed, lubrication, etc. The reference value of friction coefficient for stable rotation under general conditions is shown below. For sliding bearings, generally u = 0.01-0.02, sometimes up to 0.1-0.2. Composite bearing friction coefficient: 0.03-0.18 Bearing type Friction coefficient u Deep groove ball bearing 0.0010-0.0015 Angular contact ball bearing 0.0012-0.0020 Spherical ball bearings 0.0008-0.0012 Cylindrical roller bearings 0.0008-0.0012 Full complement needle roller bearings 0.0025-0.0035 Needle roller bearings with cage 0.0020-0.0030 Tapered roller bearings 0.0017-0.0025 Spherical roller bearings 0.0020-0.0025 Thrust ball bearings 0.0010-0.0015 Thrust spherical roller bearings 0.0020-0.0025 4、The choice of rolling bearing lubrication method Rolling bearing is an important mechanical components, a mechanical equipment performance can be fully developed depends on whether the bearing lubrication is appropriate, it can be said that lubrication is necessary to ensure the normal operation of the bearing, it plays an important role in improving the bearing capacity and service life. Regardless of the form of lubrication, lubrication in the rolling bearing can play the following role. (1) reduce the friction between the metal, slow down its wear. (2) the formation of oil film to increase the contact area, reduce contact stress. (3) to ensure that rolling bearings can be in high-frequency contact stress, a long time to normal operation, to extend the fatigue life. (4) eliminate frictional heat, reduce the working surface temperature of the bearing, to prevent burns. (5) play a dust, rust, corrosion prevention role. Therefore, the correct lubrication is very important for the normal operation of rolling bearings. The content of rolling bearing lubrication design mainly includes: the determination of reasonable lubrication method, the correct choice of lubricant, the quantitative calculation of lubricant dosage and the determination of oil change cycle. Rolling bearing lubrication can generally be divided into three categories according to the type of lubricant used: oil lubrication, grease lubrication and solid lubrication. Among them, oil lubrication has a wider temperature range than other lubrication methods, more suitable for high speed and high load conditions of the work of the bearing; at the same time, because oil lubrication also has the equipment maintenance and lubricant replacement is convenient, the system of friction vice such as gears can be lubricated at the same time, so far, the bearing using oil lubrication is the most common. Grease lubrication has the advantages of simple sealing device, low maintenance costs and low cost of grease, etc., in the low speed, medium speed, medium temperature operation of the bearing is very common. Especially in recent years, the introduction of anti-wear additives to improve the lubricating properties of grease, so that grease lubrication has been more widely used. If the use of oil lubrication and grease lubrication can not reach the required lubrication conditions of the bearing, or can not meet the specific working conditions, then you can use solid lubricants, or try to improve the lubrication performance of the bearing itself. The rotational speed of the bearing is mainly limited by the temperature rise caused by the frictional heat inside the bearing. When the rotational speed exceeds a certain limit, the bearing will not be able to continue rotating due to burns, etc. The limiting speed of a bearing is the limit value that can be continuously rotated without generating frictional heat that causes burns. Therefore, the limiting speed of a bearing depends on various factors such as the type, size and accuracy of the bearing, as well as the lubrication method, the quality and quantity of the lubricant, the material and type of the cage, and the load conditions. All kinds of bearings using grease lubrication and oil lubrication (oil bath lubrication) when the limit speed are contained in each bearing size table, the value of the standard design of the bearing in general load conditions (C/P>=13, Fa/Fr<=0.25 or so) when the rotation speed limit value.

We have rich experience on precision bearing manufacturing and are ranked NO.1 in China and NO.3 all over the world.

We can tailor the overall solution for the use of precision bearings.

HONB– Accountability & Innovation