Ball bearing vibration and noise reduction technology to improve its process equipment

At present, China deep groove ball bearing and seal products advanced internal structure parameters are almost identical, but such products in China vibration and noise levels are very different with foreign products, mainly in the manufacturing and working conditions factors. From the bearing industry point of view, condition factor can be solved reasonably requested by the host, and how to reduce the vibration caused by the manufacturer and the noise factor is the bearing industry must be addressed.

Many domestic and experiments show that: cage, ring, ball bearing vibration processing quality for different degrees of impact, where the processing quality ball bearing vibration impact on the most obvious, followed by processing quality rings, the most important influence factors and the ferrule ball roundness, waviness, roughness, surface bump and other injuries.

Ball products of the most prominent problem is the discrete vibration large, severe surface defects (single point, cluster points, pits, etc.), although the surface roughness, size, shape, the error level is not lower than the outside of the circle, but the co-sets After the bearing vibration value is high, and even produce different sound, the main problem is the waviness no control (no standards, no suitable test and analysis equipment), with an indication of poor vibration machine, grinding wheel, grinding disc, coolant, process parameters are problematic ; the other hand to improve the management level, to avoid the bump wounds, scratches, burns and other machines of any quality problems.

For the rings, the most serious impact of bearing vibration is channel waviness and surface roughness. For example, small and medium deep groove ball bearing inner channel roundness greater than 2μm, the bearing vibration will have a significant impact, both inside and outside the channel waviness greater than 0.7μm, the bearing vibration value increases with the waviness of the channel serious gouges Vibration can rise more than 4dB, and even different sound.

Both balls or rings, waviness produced in the grinding, although Superfinishing waviness can improve and reduce roughness, but the most fundamental measure is to reduce the ultra-fine grinding process of waviness, to avoid randomness bump hurt, there are two main measures:

First, reduce the rolling surface vibration when ultra-fine grinding, get a good surface finish shape accuracy and surface texture quality in order to reduce vibration, grinding super machine must have good vibration resistance, bed and other important structural parts with vibration absorption, ultra- Whetstone fine machine oscillating system has a good anti-vibration performance; improve grinding speed, grinding abroad commonly used outer raceway 6202 60,000 spindle, grinding speed 60m / s or more, domestic general much lower, mainly due to the spindle and main bearing performance limitations. In high-speed grinding, grinding force is small, thin grinding deterioration is not easy to burn, and can improve the precision and efficiency, low noise ball bearing great influence; spindle stiffness and movement speed characteristics of the low-noise ball bearing a great influence on the grinding vibration, the higher the stiffness, grinding speed on the grinding force change, the less sensitive to vibration grinding system smaller; improve spindle bearing support stiffness, random balancing technology to improve the grinding spindle vibration sex. Foreign grinding vibration velocity (eg Gamfior) is approximately one-tenth of the domestic general spindle; improve cutting and grinding wheel dressing Whetstone quality is essential. China's current wheel Whetstone main problem is poor uniformity organizational structure, seriously affecting the ultra-low-noise ball bearing grinding machining quality; sufficiently cooled, improve filtering accuracy; improve the feed to the system fine resolution, reduce the feed inertia; reasonable wear ultra-processing process parameters and machining processes are factors that can not be ignored, grinding amount to small, strictly geometric tolerance, small diameter ball bearings should not use Superfinishing, coarse grinding super not be separated to ensure good surface quality.

Second is to improve machining plane precision grinding and superfinishing process reduces error reflection of the outer end face grinding and super positioning reference during processing. The channel diameter ultra-fine error reflection on the ditch by OD grinding, grinding on the ditch ditch super error reflection indirect transitive. If the workpiece in the transfer process produces bump injury, will be directly mapped to the raceway complex machined surface, the impact of bearing vibration. So you must take the following measures: improve the positioning reference surface shape accuracy; processing passes smoothly and without a bump hurt; rough allowance form and position errors can not be too large, especially in the remaining amount is small, too large error will cause the final grinding and ultra-fine close to the final shape accuracy has not improved the quality requirements, seriously affecting the processing quality consistency.