Core-Technology｜Application Technology of Double Row Cylindrical Roller Bearings

Double row cylindrical roller bearings (NN30 series) feature a tapered bore design and are widely used in lathe spindles due to their excellent characteristics such as high precision, high rigidity, and long lifespan.

To fully leverage their performance, several critical conditions must be met, among which "full contact rate" is paramount. The industry commonly uses blue pigment (commonly known as Prussian blue) for contact inspection, targeting a contact area of 80% or more as the standard.

To further enhance spindle quality, in addition to ensuring a high contact rate, we have also developed measurement molds with an accuracy of 1 μm. These molds can effectively measure the radial expansion of the double row rollers under preload conditions, optimizing the fit between the bearings and the spindle. This ensures the precision, rigidity, and lifespan of the entire spindle while reducing temperature rise, noise, and run-in time.