Whatsapp: +86 18653126720|sales@ktaiballbearing.com

Noise and Vibration

//Noise and Vibration
Noise and Vibration 2017-03-11T15:37:46+08:00

Bearing rings and balls are not perfectly round and the balls and raceways, even after extensive fine grinding and polishing, are not perfectly smooth. There are machining imperfections in the form of rough or uneven surfaces which will cause one ring to move or oscillate radially in relation to the other. The amount and speed of this movement contributes to the amount of bearing vibration and bearing noise.  The smoothness or quietness of a bearing can be checked by accelerometers which measure bearing vibration at the outer ring, usually with the inner ring rotating at 1800 rpm.

Vibration is potentially damaging to a bearing and the equipment it is used in, increasing the rate of fatigue and shortening bearing life. Displacement measurements do not tell us enough. Vibration in a bearing or a machine will usually occur at many different frequencies and they all contribute to fatigue so we need to take all of these frequencies of vibration into account in our measurements of vibration.

A low noise/vibration rating is achieved by paying particular attention to the surface finish of the raceways and balls, the roundness of the rings and balls and correct cage design.

To help reduce noise levels even further, low noise greases are available and the choice is now greater as improved manufacturing techniques mean these greases are more finely filtered and contain fewer, smaller solid particles. These particles generate noise when they pass between the balls and raceway.

External factors such as surrounding vibration can affect bearing noise. Another problem, particularly with smaller and thin-section bearings, is ring distortion caused by poor shaft or housing roundness. Dirt or dust contamination will also increase noise and vibration levels. Poor fitting practice or incorrect handling is sometimes to blame, causing shock loads which, in turn, create scratches or dents in the raceway.

tolerance date for vibration of one bearing

dmmVV1V2V3V4
low
brand
medium
brand
high
brand
low
brand
medium
brand
high
brand
low
brand
medium
brand
high
brand
low
brand
medium
brand
high
brand
low
brand
medium
brand
high
brand
3,4804444603532482622311615281010
5,61107260744840583630352118321111
7,8,91309680926654724840442824381212
10,121601201001208070906050553530451415
15210150120150100851107860654635521818
17210150120150100851107860654635522525
2026019015018012510013010075806045602525
22,2526019015018012510013010075806045603032
2826019015018012510013010075806045603540
30,32300240190200150130150120100907560703540
35300240190200150130150120100907560704245
403603002602401801601801501301109080825050
453603002602401801601801501301109080826060
50420320320280200200210160160125100100957070

maximum vibration acceleration of one bearing

d
mm
diameter series(0)diameter series(2)diameter series(3)
ZZ1Z2Z3ZZ1Z2Z3Z4ZZ1Z2Z3Z4
33534322836353230-37363331-
43534322836353230-37363331-
53736343038373432-39373533-
63736343038373432-39373533-
73938353140383634------
83938353140383634------
94140363242403735------
104342383344423935303744403732
124443393445433935304745403732
154544403546444136314846423833
174644403547454136314947423833
204745413648464238335048433934
224745413648464238335048433934
254846423849474340365149444137
284947433950484441375250454238
304947433950484441375250454238
325048444051494542385351464339
355149454152504643395452474440
405351464254524744405654494541
455553484556544946435856514744
505754504758555148456057534946
555956524960575350476259545148
606158545162595451486461565350