1. Rolling sound Rolling sound is due to bearing rotation rolling body in the raceway rolling and excitation of a smooth and continuous noise, only when its sound pressure level or sound tone is great to attract attention. In fact, the sound energy excited by the raceway sound is limited, such as in normal conditions, high quality 6203 bearing raceway sound for 25 ~ 27dB. This noise to bear radial load single deep groove ball bearing for the most typical, it has the following characteristics: a. Noise, vibration with randomness; b. Vibration frequency in 1kHz or more; c. No matter how the speed changes, the noise main frequency almost unchanged while the sound pressure level is increased with the speed; d. When the radial clearance increases, the sound pressure level increases sharply; e. Bearing seat rigidity increases, the lower the total sound pressure level, even if Speed increases, the total sound pressure level also increases little; f. The higher the viscosity of the lubricant, the lower the sound pressure level, but for grease lubrication, its viscosity, soap fiber shape size can affect the noise value. The source of the rolling path sound generation is due to the inherent vibration of the ring after the load. As the ring and rolling body of the elastic contact constitutes a non-linear vibration system. When the lubrication or processing precision is not high will excite the inherent vibration related to this elastic characteristics, and transmitted to the air will become noise. As we all know, even if the use of the highest contemporary manufacturing technology processing bearing parts, its working surface will always exist in varying degrees of small geometric errors, so that the raceway and rolling body between the small fluctuations to stimulate the vibration system inherent vibration. Although it is unavoidable, however, can take high precision processing parts working surface, the correct choice of bearings and the precise use of bearings to reduce noise and vibration. 2. Falling body rolling sound The noise in general, mostly in the low speed and bearing radial load of large bearings. When the bearing in radial load operation, bearing load area and non-load area, if the bearing has a certain radial clearance, non-load area of the rolling body and the inner raceway does not contact, but because of the role of centrifugal force may be in contact with the outer ring, for this reason, at low speed, when the centrifugal force is less than the weight of the rolling body, the rolling body will fall and collide with the inner raceway or cage and stimulate the inherent vibration and noise of the bearing, and has the following characteristics The following characteristics a. Easy to produce when grease lubrication, not easy to produce when oil lubrication. When using poor quality grease is more likely to produce b. Often occur in winter c. For only the role of radial load and radial clearance is also easy to produce d. In a particular range will also produce and different size of the bearing its speed range is also different. e. May be continuous sound or may be intermittent sound. f. The forced vibration often excite the outer ring of the second and third order bending inherent vibration, thus emitting the noise. Through the use of pre-load method can effectively reduce the noise, reduce the radial clearance of the bearing work after installation, the use of good lubricants can also be improved, some foreign companies use light rolling body, such as ceramic rollers or hollow rollers and other technical measures to prevent this noise. 3. acoustic sound It is between the metal sliding friction produces quite violent screeching sound, although at this time the bearing temperature rise is not high, the bearing life and grease life is not much influence, but also does not affect the rotation, but unpleasant sound is disturbing, especially bearing radial load of large short cylindrical roller bearings often have this noise, its characteristics are a. bearing radial clearance is easy to produce. b. Usually appear in the grease lubrication, oil lubrication is rare. c. With the bearing size increases and decreases, and often in a speed range. d. It often occurs in winter. e. Its appearance is irregular, and unpredictable, and with the amount of grease filling and performance, installation and operating conditions related. This noise can be used to reduce bearing radial clearance and the use of shallow outer ring raceway structure to prevent. 4. Cage sound In the bearing rotation process, the free vibration of the cage and it and the rolling body or collision of the collar will issue this noise. It may appear in all kinds of bearings, but its sound pressure level is not too high and is low frequency. Its characteristics are a. Stamping cage and plastic cage can be produced. b. Whether it is thin oil or grease lubrication will appear. c. When the outer ring is subjected to bending moment is most likely to occur. d. It is easy to occur when the radial clearance is large. Because keep frame pocket hole clearance and keep frame and ring clearance in the finished bearing inevitably to exist, so completely eliminate keep frame sound is very difficult, but can reduce the assembly error, preferential selection of reasonable clearance and keep frame runout to improve. Another cage special sound is due to the cage and other bearing parts between the guide surface friction triggered by the cage self-excited vibration and the occurrence of the clamor. Deep groove ball bearing stamping cage is thin, in the radial and axial plane of the bending stiffness is low, the overall stability is poor, bearing high-speed rotation will be due to bending deformation and self-excited vibration, causing the “beeping sound”. When the bearing under radial load and poor grease performance, the initial operation will hear the “click, click” noise, which is mainly due to the rolling body in the load area, the rolling body suddenly accelerated and collision with the cage noise, this impact sound inevitable but with the operation of a period of time will disappear. Prevent cage noise measures are as follows. a. In order to make the cage rotation movement stable, should try to use the collar guide way and pay attention to give the guide surface of sufficient lubrication, the high-speed conditions of the tapered roller bearing structure to improve, the roller guide L type cage to the collar retaining edge guide Z type cage. b.When the bearing rotates at high speed, the vibration amplitude of the cage of the bearing with large pocket clearance is much larger than the vibration amplitude of the cage with small pocket clearance, so the value of the pocket clearance is especially important. c. To pay attention to minimize the radial clearance. d. Try to improve the manufacturing accuracy of the cage, improve the surface quality of the cage, help reduce the rolling body and cage collision or friction generated noise. e. Actively use advanced cleaning technology, effective and thorough cleaning of spare parts and products after the set, to improve the cleanliness of the bearing.

We have rich experience on precision bearing manufacturing and are ranked NO.1 in China and NO.3 all over the world.

We can tailor the overall solution for the use of precision bearings.

HONB– Accountability & Innovation