Radial load: acting in the direction of the bearing centerline, usually perpendicular to the axis of the bearing. In double row angular contact ball bearings, the radial load is distributed between the two contact points, with each column bearing a portion of the radial load. This allows the bearing to better balance the radial load and reduce bearing tilt damage caused by load imbalance.

Axial load: the force acting along the axis of the bearing. The design structure of double row angular contact ball bearings allows two contact points to simultaneously bear axial loads. Due to the contact angle, the bearing can withstand axial loads in two directions. The larger the contact angle of a general bearing, the stronger its ability to withstand axial loads.

Overturning moment: The moment generated by the angle deviation between the shaft and the bearing seat or external force can cause the bearing to tilt. But double row angular contact ball bearings have high rigidity, can withstand relatively large external forces, and will not easily tilt or deform.

Structural characteristics of double row angular contact ball bearings

Contact angle: The contact angle of double row angular contact ball bearings is usually between 15 degrees and 40 degrees, with 30 degrees being the most commonly used. The size of the contact angle determines the bearing's ability to withstand axial loads, and a larger contact angle can provide better axial load-bearing capacity.

Load bearing capacity: Double row angular contact ball bearings can not only withstand large radial and axial loads, but also their structural design allows the bearings to withstand certain overturning moments while limiting axial displacement of the shaft and housing.

Rigidity: Compared with single row angular contact ball bearings, double row angular contact ball bearings have better rigidity, allowing the bearing to withstand loads more stably.

Sealing performance: In order to prevent impurities from entering and ensure bearing lubrication performance, double row angular contact ball bearings usually adopt a single-layer double lip or double-layer labyrinth sealing structure, making the bearing operate more stably and have a longer service life.

Model and installation method of double row angular contact ball bearings

Model: There are multiple models of double row angular contact ball bearings, such as 7218ACD/DT, 7218B/DB, etc. These models have different sizes and outer ring designs, suitable for different application scenarios.

Installation method: The installation of double row angular contact ball bearings is more complex than that of deep groove ball bearings, mostly in pairs and requiring preloading. There are three installation forms: back-to-back, face-to-face, and series arrangement. The pre load can be obtained by grinding the end face of a ring in the bearing, or by placing two spacers of different thicknesses between the inner and outer rings of a pair of bearings, so that the steel ball is in close contact with the raceway.