Self-aligning deep groove ball bearing

Model Number: XA3221 Key Specifications/Special Features: Ball bearing (common designs)There are several common designs of ball bearing, each offering various trade-offs. They can be made from many different materials, including:stainless steel, chrome steel, andceramic(silicon nitride(Si3N4)). A hybrid ball bearing is a bearing with ceramic balls and races of metal.Deep-grooveIn adeep-grooveradial bearing, the race dimensions are close to the dimensions of the balls that run in it. Deep-groove bearings can support higher loads.Angular contactAnangular contactball bearing uses axiallyasymmetricraces.
Axial
Anaxialball bearing uses side-by-side races.

Features

This type of ball bearing is recommended when alignment of the shaft and housing is difficult and the shaft may flex. The outer ring has a spherical raceway and its center of curvature coincides with that of the bearing; therefore, the axis of the inner ring, balls and cage can deflect to some extent around the bearing center. Pressed steel cages are usually used. Since the contact angle is small, the axial load capacity is low. The permissible dynamic misalignment is approximately 0.07 to 0.12 radian (4 to 7 degrees) under normal loads. However, depending on the surrounding structure, such an angle may not be possible.

Applications

In general, ball bearings are used in most applications that involve moving parts. Some of these applications have specific features and requirement

• Hard drivebearings used to be highly spherical, and were said to be the best spherical manufactured shapes, but this is no longer true, and more and more are being replaced withfluid bearings.
• German ball bearing factories were often a target of alliedaerial bombings during World War II, such was the importance of the ball bearing to the German war industry.
• Inhorology, the companyJean Lassaledesigned a watch movement that used ball bearings to reduce the thickness of the movement. Using 0.20mm balls, the caliber 1200 was only 1.2mm thick, which still is the thinnest mechanical watch movement.
• Aerospace bearingsare used in many applications on commercial, private and military aircraft including pulleys, gearboxes andjet engineshafts. Materials include M50 tool steel (AMS6491), carbon chrome steel (AMS6444), the corrosion resistant AMS5930, 440C stainless steel,silicon nitride(ceramic) andtitanium carbide-coated 440C.
• Askateboardwheel contains two bearings, which are subject to both axial and radial time-varying loads.