The specifications of the bearing clearance

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From theoretical clearance minus the bearing installed on the shaft or shell because of the interference fit within the ring of the expansion or contraction after the clearance called "installation clearance".
Add and subtract in installation clearance for bearing internal clearance after the size change from temperature difference is called "effective clearance".
Bearing installed with mechanical clearance when placed under certain load, the effective clearance and bearing load produced by the elastic deformation of so called "work clearance".
High speed grinding to achieve two goals of modern manufacturing technology to improve product quality and labor efficiency. Practice proves: if the grinding speed increased from 35 m/s to 50 ~ 60 m/s, the general production efficiency can be increased by 30% ~ 60%, and for the durability of the grinding wheel increased about 0.7 ~ 1 times, workpiece surface roughness parameter value is about 50% lower.The advantages of rolling bearing and sliding bearing
General grinding speed reaches more than 45 m/s is called high speed grinding. Home to me the ZYS developed in the eighty s - eighty automatic bearing internal grinder, take the lead in the domestic bearing industry ferrule grinding processing and application of high speed grinding technology, successfully developed a high rigidity, high speed, high power electric spindle and high speed grinding wheel. And high speed grinding is already widely used at home and abroad, and along with the widespread adoption of high grinding ratio, high durability of superhard abrasive such as CBN, the grinding wheel grinding speed reached 80 ~ 120 m/s, is even higher. Mikrosa such as: Germany, Japan KOYO company centerless grinder, Japan TOYO company bearing internal grinder, surface grinding wheel linear velocity of 120 m/s, the inner surface grinding linear speed of 60 m/s ~ 80 m/s.
Increasing the grinding wheel drive (transmission) systems of power and improve the rigidity of machine tool is an important measure to realize high speed grinding, and the high speed spindle unit is the most key parts of high speed grinding machine. In high speed grinding, grinding wheel in addition to should have sufficient strength, also need to make sure that it has good grinding performance, high grinding effect can be attained. In addition, the cooling device is also one of indispensable to realize high speed grinding device.
When work clearance for micro negative, the fatigue life of bearing the longest but with the increase of negative clearance with a significant reduction in fatigue life. Therefore, choose the bearing clearance, general work clearance is zero or slightly is advisable.
In addition, it is necessary to improve the bearing rigidity or to reduce noise, further negative clearance to work, and when the bearing temperature rise drastically, work clearance should further positively and so on, also must make a concrete analysis according to the conditions of use.