Types of Vibration and Sound in Bearings

1 Race noise

Race noise is the most basic sound in rolling bearings. It is generated in all bearings and is a smooth and continuous sound. At CHG we say it sounds like “sha-ahh.” The magnitude of this sound is used to assess bearing quality. In this figure, even the sound generated by the loudest of the bearings, bearing #6410, is only about 1/100 of the magnitude of normal conversation. It is clear that the energy associated with race noise is very limited. The characteristics of race noise are as follows:3) 

2.Click noise

Click noise tends to occur more often in relatively large bearings under radial loads. It is generated only at low speeds, disappearing when speed exceeds a certain level. A rough approximation of this noise used at CHG is “kata kata.”  It is somewhat similar to flaw noise, which is described in a following section. The generation of click noise is believed to proceed as follows . When a bearing is operated under a radial load, then a load zone and no-load zone exist inside the bearing. The bearing has some clearance in the no-load zone-rolling elements do not touch the inner ring, but do touch the outer ring due to centrifugal force (Fc2). However, at low speeds, when centrifugal force becomes less than the force of gravity (W1), the rolling elements fall and collide with the cage and/or inner ring. It is the collisions between the rolling. 

3.Squeal noise

Squeal noise is a metallic noise that can be rather loud in some cases. It sounds like metal sliding on metal and we express it in Japanese as “kyuru kyuru.” With squeal noise, bearing temperature does not generally rise and bearing and grease life are not adversely affected. In fact,

beyond the noise problem (if indeed it is actually a problem), there is no other hindrance to bearing operation. Squeal noise tends to occur with relatively large bearings used under a radial load. It occurs frequently in cylindrical roller bearings, but may also occur in ball bearings

4.Cage noise

There are two kinds of cage noise: a noise suggestive of the cage colliding with rolling elements or bearing rings (“kacha-kacha” at CHG) and a low-frequency noise (“gaga gaga”). CHG differentiates them by calling them “CK noise” and “CG noise,” respectively. CK noise can be generated in any type of bearing and the magnitude of it is usually not very high. and Sound in BearingsEven when the most advanced manufacturing technology is used, vibration and sound still occurnaturally in rolling bearings. As such vibration and sound do not degrade bearing performance, they are accepted asnormal bearing characteristics.1 Race noiseRace noise is the most basic sound in rolling bearings. It is generated in all bearings and is a smooth andcontinuous sound. At CHG we say it sounds like “sha-ahh.”The magnitude of this sound is used to assess bearing quality. In this figure, even the sound generated by the loudest of the bearings, bearing#6410, is only about 1/100 of the magnitude of normal conversation. It is clear that the energy associated withrace noise is very limited. The characteristics of race noise are as follows:3) 2.Click noiseClick noise tends to occur more often in relatively large bearings under radial loads. It is generated only at lowspeeds, disappearing when speed exceeds a certain level. A rough approximation of this noise used at CHG is “kata kata.” It is somewhat similar to flaw noise, which is described in a following section. The generation of click noise is believed to proceed as follows . When abearing is operated under a radial load, then a load zone and no-load zone exist inside the bearing. The bearing hassome clearance in the no-load zone-rolling elements do not touch the inner ring, but do touch the outer ring due tocentrifugal force (Fc2). However, at low speeds, when centrifugal force becomes less than the force of gravity(W1), the rolling elements fall and collide with the cage and/or inner ring. It is the collisions between the rolling.3.Squeal noiseSqueal noise is a metallic noise that can be rather loud in some cases. It sounds like metal sliding on metal andwe express it in Japanese as “kyuru kyuru.” With squeal noise, bearing temperature does not generally rise andbearing and grease life are not adversely affected. In fact,beyond the noise problem (if indeed it is actually a problem), there is no other hindrance to bearing operation.Squeal noise tends to occur with relatively large bearings used under a radial load. It occurs frequently in cylindricalroller bearings, but may also occur in ball bearings4.Cage noiseThere are two kinds of cage noise: a noise suggestive of the cage colliding with rolling elements or bearing rings(“kacha-kacha” at CHG) and a low-frequency noise (“gaga gaga”). CHG differentiates them by calling them “CKnoise” and “CG noise,” respectively. CK noise can be generated in any type of bearing and the magnitude of it isusually not very high.