angular contact bearings
Angular Contact Bearings
Angular contact bearings are designed such that there is an angle between the races and the balls when the bearing is in operation. An axial load passes in a straight line through the bearing, whereas a radial load takes an oblique path that tends to want to separate the races axially. So the angle of contact on the inner race is the same as that on the outer race. Angular contact bearings are typically assembled with a thrust load or preload. The preload creates a contact angle between the inner race, the ball and the outer race. The preload can be done while manufacturing the bearing or it can be done when the bearing is inserted into an application.
The contact angle is measured relative to a line running perpendicular to the bearing axis. Angular contact bearings are capable of withstanding heavy thrust loads and moderate radial loads. The larger the contact angle (typically in the range 10 to 45 degrees), the higher the axial load supported, but the lower the radial load. In high speed applications, such as turbines, jet engines, dentistry equipment, the centrifugal forces generated by the balls will change the contact angle at the inner and outer race.
Angular contact ball bearings have raceways in the inner and outer rings that are displaced with respect to each other in the direction of the bearing axis. This means that they are designed to accommodate combined loads, i.e. simultaneously acting radial and axial loads.The axial load carrying capacity of angular contact ball bearings increases with increasing contact angle. The contact angle α is defined as the angle between the line joining the points of contact of the ball and the raceways in the radial plane, along which the load is transmitted from one raceway to another, and a line perpendicular to the bearing axis.
SINGLE ROW ANGULAR CONTACT
Single row angular contact ball bearings feature raceways with high and low shoulders. These opposing raceways are designed to carry thrust load in one direction. NTN can preload the bearings at the factory so that the correct load will develop once the bearing is put into service. The bearings in this series are assembled with a specific internal clearance, so that they will have a specified contact angle under load. The standard contact angle used by NTN is 30° but, in many cases, a 40° contact angle can also be specified. We also offer special high-speed bearings with phenolic resin cages with a 15° contact angle.
DOUBLE ROW ANGULAR CONTACT
Double row angular contact ball bearings have an inner and outer ring with a double raceway. The two rows are so related that the contact angle is similar to a pair of back-to-back single row bearings. NTN’s 5200 and 5300 series offer continuous races and can carry thrust loads in either direction. The 3200 and 3300 series have filling slots, so it is necessary to mount them with the thrust load acting against the un-notched face of the rings.
SKF angular contact ball bearings are produced in a wide variety of designs and sizes.
Those commonly used and included in this catalogue are
– single row angular contact ball bearings
– double row angular contact ball bearings
– four-point contact ball bearings
