The speed of NSK bearingsare mainly caused by the friction heat of the bearing within the limits of temperature rise, when the speed exceeds a certain threshold, the bearings due to burns and can not continue to rotate. Bearing the speed limit does not generate friction heat can cause burns continuous rotation of the limit value.
Therefore, NSK bearing speed limit depends on the quality and quantity of type, size, and accuracy and lubrication of bearings, lubricants, materials and type of cage, load conditions and other factors. Limiting speed when the various types of bearings with grease and oil lubrication (oil bath lubrication) are set out at NSK Bearings size table, its value indicates the standard design bearing normal load conditions (/ P> = 13 Fa / Fr < = 0.25) under rotation speed limit value. In addition, the lubricant according to the different types and grades may also be, although better than the other properties but not for high-speed rotation.
Amendment to limit speed load conditions C / P <13 (equivalent dynamic axial load in the load P exceeds the basic rated dynamic load C, 8%), or under the combined load more than 25% of the radial load, use the following formula be amended to limit speed. na = f1 * f2, * na n-here: the revised limit speed, rpm for f1,: load conditions, the correction factor f2: combined load correction factor n: limit speed under normal load conditions, rpm (reference NSK Bearings Size Chart): The basic dynamic load rating, N {kgf} P: equivalent dynamic load, N {kgf} Fr: radial load, N {kgf} Fa: axial load, N {kgf} with a ring ball NSK Bearings the limits of speed with contact seals (RS type) ball NSK bearing speed limit speed limits of the ring contact surface line to allow line speed depends on the rubber material of the ring.
High-speed rotation Note NSK bearings rotating at high speed, especially speed close to or exceed the size of table records the limit speed, the principal should pay attention to the following matters:
(1) the use of precision bearings
(2) analysis of the NSK bearing internal clearance (taking into account the temperature rise produced by NSK bearing internal clearance reduction)
(3) analysis of the type of cage materials (for high-speed rotation, suitable for cutting of copper alloy or phenolic resin cage. There is also a synthetic resin molding for high-speed rotating cage)
(4) analysis of lubrication methods (for high-speed rotation cycle lubrication, spray lubrication, oil mist lubrication and oil lubrication lubrication methods) NSK bearings coefficient of friction (Reference) In order to facilitate and sliding bearings, rolling bearing friction torque can be bearing bore diameter by the following formula: M = uPd / 2 here M: friction torque, mN.m {kgf.mm} u: friction coefficient, NSK bearing load, N, {kgf} d: NSK Bearings public inside diameter, mm friction coefficient u by the NSK bearing type, NSK bearing load, speed, lubrication methods of the larger.
Other News:
Analysis of the relationship of the limit speed of NSK bearings and friction coefficient
INA bearings damage degree judgement skills
Checking method for the failure of FAG bearings and hardening of the cooling medium
Brief introduction of NSK bearings hot greasy method
TIMKEN bearings accuracy grade selected
Standard installation methods and periodic lubrication maintenance of NSK bearings
FAG bearing several problems should be paid attention
＂TIMKEN bearings should be replaced,＂ the judgement method
