In the 608 series, the ball bearing typically consists of optional closures, inner race, outer race, balls, and ball retainer. It is characterized by an 8mm inner diameter, a 22mm outer diameter, and a width of 7mm. Most of these ball bearings are manufactured to reflect an ABEC rating which is the industry standard to measure the dimensional and manufacturing tolerances of ball bearings.
Materials Used in the 608 Bearing
Ball bearings are made of a variety of material types, including ceramic and metal. Ceramic ball bearings are generally recognized as superior because they can dissipate the heat and friction generated inside a ball bearing more easily than a normal metal ball bearing can. For purposes of normal usage however, a 608 ball bearing typically consists of chrome steel balls, both for durability and economic reasons, as a ceramic ball bearing can be quite expensive. Keeping your bearing clean and lubricated will make it work better and last much longer.
How a 608 Bearing Functions
In a 608 bearing, the bearing balls rotate between two rings – an inner ring and outer ring – and are kept apart by a metallic crown type “H” or a two piece metallic ribbon type “R” cage which are interchangeable in most common applications. The entire unit is sealed with a rubber or metal shield. This shield is helpful in reducing the entry of particulate contaminants into the bearing and also reduces the amount of lubricant leakage.