Influence of bearing structure on the vibration and noise(one).

The 1 raceway acoustic

Rolling road sound is due to rotation of the single direction thrust ball bearing body raceway rolling in and create a smooth and continuous noise, only when the sound pressure level or tone greatly when attention. In fact, the rolling sound excited acoustic energy is limited, such as in the normal condition, the quality of the 6203 bearing raceway acoustic ranged from 25 to 27dB. Single row deep groove ball bearing this noise to bear radial load as the most typical, it has the following characteristics:

A. noise, vibration is random;

B. vibration frequencies above 1kHz;

C. No matter how changes in speed, noise frequency and sound pressure level is almost the same with the speed increase;

D. when the radial clearance increases, the sound pressure level increases sharply;

Rigid E. bearing increases, the lower the total sound pressure level, even if the speed increased, the overall sound pressure level increases slightly;

F. lubricant viscosity is high, the sound pressure level is low, but for grease lubrication, the shape and size of the viscosity, the soap fiber can affect the value of the noise.

Rolling road sound source is the inherent vibration caused by load ring after. Due to the elastic contact rings and rolling elements of nonlinear vibration system. When the lubrication or machining precision is not high it will inspire the vibration associated with the elastic characteristics, transfer into the air into a noise. As everyone knows, even using the modern technology of manufacturing the highest machining bearing parts, its work surface there are tiny geometric error is not a degree, so that the raceway and rolling body produce tiny wave excitation vibration vibration system. Although it is inevitable, however, can adopt high precision machining parts work surface, the correct selection of denoising bearing and precise use of the bearing so that the damping.

2 fall rolling sound

The noise in general, mostly large bearings at low speeds and bear radial load. When the operation of the bearing in the radial load, load and non load bearing, if the bearing has a radial clearance, the non load area of the rolling body and the inner raceway no contact, but because of the action of centrifugal force may be associated with the outer ring contact, therefore, at low speeds, the centrifugal force is less than when rolling body weight when the natural vibration and noise, the rolling of the fall and and inner raceway or cage collision and motivate the thrust roller bearing, and has the following characteristics:

Easy to produce A. grease lubrication, oil lubrication is not easy to produce. When use inferior lubricating grease are more susceptible to.

B. often occurred in winter.

C. for only the radial load and the radial clearance is large but also easy to produce.

D. also can be in a certain range and different size bearing its speed range are also different.

E. may be a continuous sound may be intermittent sound.

F. the forced vibration often excited outer two order, three order bending vibration, thus make the noise. Through the use of pre load equation method can effectively reduce the noise, reduce the installed bearing radial clearance, choose good lubricants can also improve, some foreign enterprises adopt light rolling body, such as ceramic roller or hollow roller and other technical measures to prevent the occurrence of such noise.

The 3 tip.

It is a metal sliding friction produced quite sharp scream, though bearing temperature rise is not high, it will not have much impact on the service life of the bearing and grease life, does not affect the rotation, but not melodious sound disturbing, especially bear radial load of large cylindrical roller bearings often have this noise, the characteristics of:

A. bearing radial clearance large easy to produce.

B. usually occurs in grease lubrication, oil lubrication is rare.

C. decreases with the bearing size increases, and often appears in a certain speed range.

D. winter often.

E. its appearance is irregular, and unpredictable, and associated with the installation of operating conditions and performance, filling grease amount. This noise can be used to reduce the bearing radial clearance and the shallow outer ring raceway structure to prevent.‍