small ball bearings are miniature bearings with balls as their rolling elements. These small bearings have an outside diameter of less than 3/8″ (<9.525 mm) or are small bearings with an outside diameter less than or equal to ½” (≤ 12.7 mm) having a ratio of outside diameter to an inside diameter equal to or less than two.
The main materials are carbon steel, bearing steel, stainless steel, plastics, ceramics, etc.
Common types of miniature bearings
682 682ZZ MR52 MR52ZZ 692 692ZZ 683 683ZZ MR83 MR83ZZ 693 693ZZ 603 603ZZ 623 623ZZ MR74 MR74ZZ MR84 MR84ZZ 684 684ZZ MR104 MR104ZZ 694 694ZZ 604 604ZZ 624 624ZZ MR85 MR85ZZ MR95 MR95ZZ MR105 MR105ZZ 685 685ZZ MR115ZZ 695ZZ 605ZZ 625ZZ MR106 MR106ZZ MR126 MR126ZZ 686 686ZZ 696ZZ 606ZZ 626ZZ MR117 MR117ZZ MR137 MR137ZZ 687 687ZZ 607ZZ 627ZZ MR128 MR128ZZ MR148 MR148ZZ 688 688ZZ 698ZZ 608ZZ MR149 MR149ZZ 689 689ZZ 609ZZ 629ZZ 639ZZ
Why miniature bearings failure
About 40% of the failures of small ball bearings are caused by dust, dirt, debris contamination, and corrosion. pollution is usually caused by incorrect use and poor use environment. It can also cause torque and noise problems. miniature bearing failures caused by the environment and pollution can be prevented, and the cause of such failures can be determined by simple visual observation. as long as the use and installation are reasonable, the erosion of the miniature bearing is easy to avoid.
The feature of erosion is that there are indentations on the raceway of the miniature bearing ring caused by impact load or incorrect installation. erosion usually occurs when the load exceeds the yield limit of the material. if the installation is not correct so that a certain load traverses the miniature bearing ring, corrosion will also occur. pressure pits on the miniature bearing ring can also generate noise, vibration, and additional torque.