Non-Standard Bearings When the bearing rotates
Roller sound is due to TIMKEN deep groove ball bearings when the rolling body rolling in the raceway to stimulate a smooth and continuous noise, only when the sound pressure level or tone is very high when it attracts attention. In fact, the sound of the raceway sound is limited, such as under normal circumstances, high-quality 6203 bearing raceway sound of 25 ~ 27dB. This kind of noise to bear the radial load of single row deep groove ball bearing is the most typical, it has the following characteristics:
Noise, vibration is random;
B. Vibration frequency above 1kHz;
C. Regardless of how the speed changes, the main frequency of the noise is almost constant and the sound pressure level increases with increasing speed;
D. When the radial clearance increases, the sound pressure level increases sharply;
E. The rigidity of the bearing block increases, the lower the total sound pressure level, even if the speed increases, the total sound pressure level also increased little;
F. The higher the viscosity of the lubricant, the lower the sound pressure level, but for grease lubrication, its viscosity, soap fiber shape can affect the size of the noise value.
Roller sound source is due to the load after the ring caused by the inherent vibration. The elastic contact of the ferrule and the rolling element constitutes a nonlinear vibration system. When the lubrication or processing accuracy is not high will stimulate the elastic characteristics associated with the inherent vibration, into the air into noise. As we all know, even with the most high-end manufacturing technology to produce TIMKEN deep groove ball bearing parts, the working surface will always exist in varying degrees of small geometric error, so that the raceway and rolling between the tiny fluctuations in vibration vibration system inherent vibration The
Although TIMKEN deep groove ball bearing raceway noise is inevitable, but can take high-precision machining parts of the working surface, the correct choice of bearings and precision bearings to noise reduction.
SKF bearing size accuracy and rotation accuracy is based on ISO and JIS standards. For machinery requiring high precision and high speed operation, it is recommended to use SKF bearings with 5 or more precision, deep groove ball bearings, radial thrust ball bearings or cylindrical roller bearings for high precision machining. Rigid, when the SKF bearings of the rolling body and raceway contact surface pressure, will produce elastic deformation. Some machines need to minimize elastic deformation. The roller bearing is smaller than the elastic deformation caused by the ball bearing.
In addition, in some cases, SKF bearings are subject to preload to increase rigidity. This procedure is usually used for deep groove ball bearings, radial thrust ball bearings and tapered roller bearings inner and outer ring bias, shaft bending, shaft or bearing box tolerance changes, with the error will lead to eccentric inner and outer ring. To prevent eccentricity is too large, self-aligning ball bearings, self-aligning roller bearings, or aligning bearing housings are the preferred choice. Voice frequency and torque, rolling bearings are manufactured according to high precision standards, so the voice and torque is small. Deep groove ball bearings, and cylindrical roller bearings for low voice, low torque have special requirements of the occasion.