Angular contact ball bearings can bear predominate radial load and subsidiary axial load from both directions. This type is able to work at higher speeds. The greater the contact angle, the higher the axial bearing capacity. The contact angle is the angle between the contact point line of the ball and raceway in the radial plane and the vertical line of the bearing axis. High-precision and high-speed bearings usually take a 15-degree contact angle. The contact angle will increase under the action of axial force.