Bearing limit speed and limiting speed correction and the matters needing attention

1, bearing the limit speed of the speed of the bearing is mainly caused by bearing the internal friction heat temperature limits, when the speed exceeds a certain limit, the bearing will can't continue to rotate for burns, etc. Bearing limit rotational speed is not burned to produce friction heat and the threshold of the continuous rotation speed. Therefore, bearing limit speed depends on the type, size, and precision bearings and lubrication method, the quantity and quality of the lubricant, materials and types of cage, load conditions and other factors. All kinds of bearing with grease lubrication and oil lubrication ( Oil bath lubrication) When the limit speed, respectively in each table bearing size. Its numerical representation standard design of bearing in the general load conditions, C/P≥13，Fa/Fr≤0. 25 or so) The threshold of the next rotation speed. In addition, the lubricant according to their kinds and brands, may also is superior to other performance but is not suitable for high speed rotation. 2, fixed load conditions of the bearing limit speed C/P< 13 ( The equivalent dynamic load P more than about 8% of the basic dynamic load rating C) 。 Or synthetic load under the axial load in more than 25% of radial load, want to use ( 1) To modify the limit speed. Na: the limit of the revised RPMFL; Correction factor related to the load conditions, FIG. 1) F2: correction factor related to the synthetic load ( FIG. 2) N: general load under the condition of limit speed. RpmC: basic dynamic load rating, N { kgf} P: equivalent dynamic load, N { kgf} Fr: radial load, N { kgf} Fa: axial load, N { kgf} 3, high-speed rotating note bearing rotating at high speed, especially the switch element is close to or exceeds the limit speed of the dimension table records, main attention should be paid to the following matters: ( 1) Use the precision bearing ( 2) Analysis of bearing internal clearance ( Considering the temperature rise of bearing internal clearance to shout a few) ( 3) Analysis of the cage material type ( For high-speed rotation, suitable for use of copper alloy cage or phenolic resin system. But there are also suitable for high rotary cage resin forming) ( 4) Analysis of lubrication methods ( Lubrication is suitable for high speed rotating cycle, spray lubrication, and lubrication oil mist lubrication and oil lubrication methods) ( 5) Cage or phenolic resin system. But there are also suitable for high speed rotating cage resin forming) Analysis of lubrication methods ( Lubrication is suitable for high speed rotating cycle, splash lubrication, and lubrication oil mist lubrication and oil lubrication methods.