6004 Nachi Bearing Open C3 Japan 20x42x12

Deep Groove ball bearings are the most popular of all the ball bearing types because they are available in a widevariety of seal, shield and snap-ring arrangements. The bearing ring grooves are circular arcs made slightly larger than the radius of the ball. The balls make pointcontact with the raceways (elliptical contact when loaded). The inner ring shoulders are of equal height (as theouter ring shoulders). Deep Groove ball bearings can sustain radial, axial, or composite loads and because of simple design, thisbearing type can be produced to provide both high-running accuracy and high-speed operation. Deep Groove ball bearings having an outside diameter less than 9 mm are known as Miniature ball bearings. Deep Groove ball bearings having an outside diameter => 9 mm and a bore diameter < 10 mm are known asExtra-small ball bearings. Standard ball retainers (cages) are made from pressed steel. Machined cages are used in bearing operating atvery high speed or for large diameter bearings. Deep groove ball bearings with seals or shields are standardized. They contain proper amount of grease inadvance.