Spindle bearings

Spindle bearings are special angular contact ball bearings with a high manufacturing accuracy. They are often used for bearing spindles in machine tools, hence the name: spindle bearings. Typical contact angles are 15° and 25°. Some manufacturers also use a deviating contact angle of 21°. Clearance-free operating states can be achieved on the basis of the tight manufacturing tolerances. For this, spindle bearings are manufactured in different preload classes. In their installed state, they are then preloaded clearance-free (light, medium, heavy). The higher the preload, the higher is the rigidity of the bearing. Spindle bearings with a small contact angle are suitable for higher speeds. Spindle bearings with a larger contact angle are suitable for greater axial loads. 

Smaller rolling elements and the use of modern materials (e.g. ceramic) allow speed limits to be increased even further, at the cost of load capacity (hybrid bearings). 

Spindle bearings are often used in environments where no additional heat may be produced (danger of thermal expansion). Hybrid bearings are usually used for such applications. Modern spindle bearing designs also permit grease lubrication (maintenance-free). This allows speed parameters (mean bearing diameter x speed) of more than one million to be achieved. The complete performance spectrum of spindle bearings can only be exploited if the processing quality of the conversion parts is within the respective manufacturing tolerance.