What is ABEC 7?
ABEC ratings have to do with the quality and precision of the bearing. ABEC 7 bearings are also referred to as “Super Precision Bearings” and are equivalent to ISO P4. These bearings are specifically designed for machine tool applications. Typically they are purchased in matched sets or quad sets. HST always uses ABEC 7 or ABEC 9 (Super High Precision, ISO P2) bearings. When assembling Super Precision Bearings the manufacturer matches the balls to the races using a very tight tolerance. Although assembled on high speed equipment each Super Precision Bearing is a “custom” assembly. Each race is individually measured to better than 1 µm and then assembled with balls that exactly match the race variation. That is just one of the factors that influence the price of the ABEC 7 bearings. It is not uncommon for bearings in a medium size spindle to cost over $2000. HST uses matched set bearings. These are bearings that are ground together in the same operation. There is a move in the industry
