1.Deep groove ball bearing

This type of bearing is generally only used to bear radial load. Because the clearance is not adjustable, it is often used in applications where accuracy is not high and no pre-tightening is required, such as ordinary drilling machine spindles.

2. Angular contact ball bearings

These bearings can withstand both radial and axial loads, and will cause internal axial forces when subjected to radial loads, so they should be installed and used in a “back-to-back”, “face-to-face”, “series” and “ Multiple joints, etc., and the pre-tightening can increase the rigidity of the spindle. The contact angles of these bearings are 15°, 25° and 40°. The B7000CY high-precision angular contact ball bearings with a contact angle of 15° are special bearings specially designed for high-speed grinding spindles. In addition, the ferrules and rolling elements are made of high quality electroslag bearing steel. The cage material is a phenolic laminate tube with tolerance classes of 5, 4 and 2. Therefore, this type of bearing has high rotation accuracy and limit rotation speed, low friction and low temperature rise.

3. Two-way thrust angular contact ball bearing

A 230,000 type two-way thrust angular contact ball bearing is usually used with a contact angle of 60°. It consists of a seat with a lubricating oil hole, two shaft rings, a spacer ring and two sets of steel ball and cage assemblies. Choosing the right spacer height allows the bearing to have the required preload after assembly.

This type of bearing can withstand two-way axial load, has good rigidity, low temperature rise during normal lubrication, high speed, and easy to assemble and disassemble. As a new structure, it is currently used for grinding machines, lathes, boring machines, milling machines, drilling machines and other spindles. On the top, it is often used in combination with double row cylindrical roller bearings.

4. Double row cylindrical roller bearing

These bearings can withstand large radial loads and allow for higher rotational speeds. The two rows of rollers in the bearing are arranged in a crosswise manner. The frequency of the wave can be doubled compared to the single row bearing and the amplitude is reduced by 70%. There are two types of such bearings commonly used: NN30/W33, NN30K/W33 two series bearing inner ring with ribs, outer ring can be separated; NNU49/W33, NNU49K/W33 two series bearing outer ring with ribs, inside The ring can be separated, wherein the inner ring of NN30K/W33 and NNU49K/W33 series is a tapered hole (taper 1:12), which cooperates with the tapered journal of the main shaft, and moves the inner ring axially to make the inner ring swell. Small bearing clearance even pre-tightens the bearing. Cylindrical bore bearings are usually hot-fitted, with an interference fit to reduce bearing clearance or to achieve pre-tightening. NNU49 series bearings that can be separated from the inner ring are generally finished with the raceway after the inner ring is mounted on the inner ring to obtain high spindle rotation accuracy.

5. Tapered roller bearing

It can withstand both radial and axial loads, and double row tapered roller bearings can withstand biaxial axial loads. Due to the sliding friction between the large end of the tapered roller and the rib of the inner ring, the limit rotation speed is often lower than that of the cylindrical roller bearing of the same size. Hollow tapered roller bearings can be cooled with oil to lower the temperature rise, thus increasing the allowable speed. However, this kind of bearing manufacturing process is complicated, and the requirements for the lubrication system of the machine tool are also high, and generally only used for the horizontal spindle with special requirements.