NSK bearing lubrication plan and key points of the installation and use of the grease - bearing knowledge

Lubrication of NSK bearings, especially the fatigue life of rolling bearing, friction and wear, temperature rise, vibration and so on have important influence. No normal lubrication, bearing cannot work. The failure reasons of NSK bearings shows that about 40% of the bearing damage is related to bad lubrication. Therefore, NSK bearings for good lubrication is an effective measure to reduce the bearing friction and wear. In addition, NSK bearing lubrication and cooling, a variety of action such as rust, seal, moderate impact. The effect of NSK bearing lubrication can be briefly stated below. The contact between two rolling or sliding surface formed between a layer of oil film separates two surface, reduce the friction and wear of contact surface. b。 Using oil lubrication, especially the circulating oil lubrication, oil mist lubrication and oil lubrication, the bearing lubricating oil take most of the internal friction heat, effective heat dissipation effect. c。 Using grease lubrication, can prevent external dust and other foreign body into the bearings, sealing effect. d。 Lubricant function to prevent corrosion of metal. e. Extend the fatigue life of NSK bearings. A, installed on the surface and asked if the bearing with iron filings, burr, dust and other foreign matter to enter, will make the bearing noise and vibration during operation, and even damage raceway and rolling body. So, before the installation of bearings, you must ensure that the installation surface and the environment clean. Second, the bearing must be cleaned before installed bearing surface coated with anti-rust oil, you must clean with clean petrol or kerosene carefully, then coated with clean, high quality or high speed high temperature lubricating grease before installation. NSK bearing life and cleanliness of the influence of vibration noise is very big. But we especially want to remind you is: fully enclosed bearing not clean fuel. Three, the choice of the grease lubrication NSK bearings for work and life have very important influence, this to you a brief introduction to the general principles of the grease choice. Grease made out of base oil, thickener and additive, different types and different type of same kind grease properties vary widely, allowing the rotation of the limit, when the choice is important to note. The performance of the grease is mainly composed of base oil, the basis of generally low viscosity oil is suitable for low temperature, high speed, high viscosity is suitable for high temperature, high load. Thickener and relationship with lubrication performance, thickening agent, water resistance to the water resistance of the grease. In principle, different brand of grease can't mix, and even the same thickening agent of grease, will also bring bad influence each other on the basis of different additives. Four, grease add lubrication bearing, oil paint, the more the better, this is a common mistake. NSK bearings and bearing indoor excessive grease will cause excessive oil mixing, resulting in a high temperature. The number of bearing lubricant filling with full of bearing internal space 1/2 ~ 1/3 advisable, high speed should be reduced to one-third. Five, the installation and remove bearing NSK bearings do not directly hammer end face and the bearing surface, should be to press, sleeve or other installation tools for uniform bearing force, not by rolling body power installation. If the installation surface coated with lubricating oil, will make the installation more smoothly. If the interference fit is larger, should put the bearing into the mineral oil in installation as soon as possible after heating to 80 ~ 90 ℃, strictly control the oil temperature does not exceed 100 ℃, in order to prevent the effect of tempering hardness decrease and recovery effect size. When removing difficulties, it is recommended that you use disassembly tool to pull at the same time to careful labor the inner ring of hot oil, heat can make the bearing inner ring expansion, making it easier to fall off. Six, bearing radial clearance choice not all NSK bearings require minimum clearance to work, you must choose appropriate clearance according to conditions. National standard 4604 - In 93, the rolling bearing radial clearance is divided into five groups 2, 0, 3, 4, 5, clearance values in sequence from small to large, including standard clearance for 0 group. Basic radial clearance group applicable to the general operation conditions, the conventional temperature and the range of the commonly used; In the high temperature, high speed, low noise, low friction bearing special conditions such as work, appropriate chooses big radial clearance; For precision NSK bearing spindle, machine tool spindle with appropriate chooses the smaller radial clearance; For roller bearing clearance can keep a small amount of work. In addition, the separation type of bearing is not clearance; In the end, the bearing capacity after work clearance, than the original clearance before the installation is small, because bearings will absorb a certain amount of load, and bearing fit and load produced by the elastic deformation.