Super precision high load capacity angular contact ball bearings are divided into two series, 719.D (SEB) and 70.D (EX), the bearings of these two series like Precision spindle bearings have two contact angles, two kinds of ball materials and two kinds of ring materials , and can be manufactured into two tolerance classes, most bearings come standard with phenolic resin cages, except for the three largest bearings, these bearings have machined brass cage versions, common sizes also have PEEK resin cages, to Adapt to higher bearing operating temperatures.

Precision spindle bearings for machine tools---Machine tool spindle bearings, as the name implies, are bearings used on machine tool spindles, which usually have many advantages such as high speed, high precision, strong bearing capacity, pressure resistance, high temperature resistance, and large volume... Machine tool The following types of spindle bearings are common: 1. Deep groove ball spindle bearings 2. Angular contact ball spindle bearings 3. Two-way thrust angular contact ball spindle bearings 4. Double row cylindrical roller spindle bearings 5. Tapered roller spindle bearings.

When the inner ring of the spindle bearing of a high-speed machine tool is tightly fitted to the shaft, and the outer ring is loosely fitted to the bearing seat hole, the bearing can be first pressed onto the shaft by a press, and then the shaft together with the bearing is put into the bearing seat hole and pressed. When installing, on the surface of the inner ring of the bearing, the assembly sleeve made of soft metal material (copper or mild steel), the inner diameter of the assembly sleeve should be slightly larger than the diameter of the journal, and the outer diameter should be slightly smaller than the rib of the inner ring of the bearing , so as not to press on the cage.

To improve the accuracy of precision bearings for machine tools, NTN has designed an ultra-high precision bearing. Using the mutual difference in the diameters of one bearing rolling element, the angular component of the roundness of the bearing ring is controlled to reduce the non-repeatable runout accuracy (N.R.R.O: Non-Repetitive Run-Out) of the bearing. NTN will support non-repeatable runout accuracy bearings of 0.3 μm or less for use in ultra-high precision machining centers and lathe spindles.