Reach the accuracy level P4S: At a rough level, the accuracy of the bearing is basically covered by DIN/ISO or ABEC standards. But the super precision bearings exceed this range. In addition to the tolerances required to achieve P4 or higher accuracy levels, there are other properties that are not included in these standards. All important product properties of super-precision bearings meet the P2 accuracy level. The same is true for the running accuracy and parallelism of bearings produced in accordance with the P4S standard. Therefore, standard super-precision bearings can be used in the highest-precision bearing arrangement design. (See tolerances of single-row spindle bearings, page 144) Suitable material: Super precision bearings are made of high-performance materials. Through a special heat treatment process to obtain high material fatigue life and wear resistance, in this way, under normal circumstances, the bearing can run under unlimited life. Cronidur 30 is a particularly important material, and X-life ultra-long-life ultra-precision bearings are made from it. Its unprecedented fatigue strength and corrosion resistance greatly increase the service life of the bearing, allow higher contact stress, higher allowable speed and significantly increase the service life of the lubricant. Nowadays, for spindle bearings, for example, hybrid bearings composed of steel bearing rings and ceramic rolling elements have become a standard product. Ceramic rolling elements are also used in cylindrical roller bearings. The ceramic material used is silicon nitride, which can give full play to the typical ceramic characteristics. Compared with steel rolling elements, it has more advantages, such as: Excellent friction performance between steel and ceramic, which greatly reduces the stress of materials and lubricants in hybrid bearings. The low density of ceramic reduces the centrifugal force of the rolling elements and improves the motion performance of the bearing. The thermal expansion coefficient of ceramic balls is low. During operation, temperature changes have little effect on bearing preload changes. The above factors greatly extend the life of the bearing. Therefore, ceramic ball bearings are often used even at low speeds. Lubrication Grease plays an important role in the entire bearing system. Whether to use grease lubrication or oil lubrication has a great influence on the cost of the system. The goal of the Schaeffler Group is to allow and prefer grease lubrication even at maximum speeds. Lubricants must undergo strict verification procedures before they are used. Calculations and suitability tests for specific application requirements, such as temperature performance and running-in performance of high-speed rotating spindles, are very important in the entire process. The result of this complex process is that the technical parameters of the lubricant to be verified are verified, and its accurate suitability is guaranteed through continuous testing. The spindle bearing is a single row angular contact ball bearing with high precision. The external dimensions have been standardized, so it can be interchanged with other similar products on the market. It has the world's most mature and comprehensive product range of high-precision bearings for machine tool spindles, which represents the highest level of technology. Can provide bearings for almost all spindle designs on the market. Therefore, the selection of spindle bearings can meet the requirements of most specific applications. The contact shape, material selection, surface quality and lubricant feed of this type of bearing have the following advantages: high precision, excellent high speed performance, high rigidity, and good seismic performance.