Angular Contact Ball Bearings
Overview
NSK's comprehensive range of angular contact ball bearings is designed to meet the ever-evolving requirements of equipment manufacturers.
Angular contact ball bearings feature a contact angle that sustains significant axial loads in one direction at the same time as radial loads.
Since an axial component is generated when radial load is applied, these bearings are typically used in pairs or multi-bearing sets.
Product List
The structure of angular contact ball bearings produces an axial component when a radial or combined load is applied; therefore, two opposed bearings or a multi-bearing arrangement are used.
A preload is often used to increase the rigidity of single-row angular contact ball bearings, particularly in the main spindles of machine tools where high running accuracy is crucial.
Bearings with a contact angle of 30° (A) or 40° (B) typically use pressed steel, molded resin, or machined brass cages, though machined synthetic resin or specialized polyamide resin cages are used for certain applications.
Reference 1 Cages for Angular Contact Ball Bearings by Series
| Series | Pressed Steel Cages | Machined Brass Cages |
|---|---|---|
| 79A5,C | - | 7900-7940 |
| 70A | 7000-7018 | 7019-7040 |
| 70C | - | 7000-7022 |
| 72A,B | 7200-7222 | 7224-7240 |
| 72C | - | 7200-7240 |
| 73A,B | 7300-7320 | 7321-7340 |
Features
- Support both radial and axial loads
Single-row ACBBs can take radial loads and axial loads in one direction with typical contact angles of 30° or 40°. - A variety of contact angles
Larger contact angles offer greater capacity for axial loads, while smaller contact angles are better for high-speed rotation. - Two opposed bearings are used to adjust internal clearance. Pressed steel cages are common, though polyamide resin cages are typically used for high-precision bearings with contact angles under 30°.
Applications
- High rigidity
Ideal for applications requiring bearing rigidity. - Pumps, compressors, screw chillers, elevator hoists
Matched angular contact ball bearings come in a variety of arrangement types to suit loads for a partciular application.
Types and Features of Matched Angular Ball Bearings
Arrangement
Back-to-back (DB)
Example: 7208 A DB
Features
Radial loads and axial loads in both directions can be sustained.
Since the distance between the effective load centers a0 is large, this type is suitable if moments are applied.
Arrangement
Face-to-face (DF)
Example: 7208 B DF
Features
Radial loads and axial loads in both directions can be sustained.
Compared with the DB Type, the distance between the effective load centers is small, so the capacity to sustain moments is inferior to the DB Type.
Arrangement
Tandem (DT)
Example: 7208 A DT
Features
Radial loads and axial loads in one direction can be sustained. Since two bearings share the axial load, this arrangement is used when the load in one direction is heavy.
Features
- Flexible arrangements
Angular ball bearing sets are defined by how the bearings are oriented when combined. Bearings can be arranged with their outer ring front faces together (face-to-face/DF), with their back faces together (back-to-back/DB), or with faces aligned in the same direction (tandem/DT). - Support axial and radial loads
DF and DB arrangements can sustain radial loads and axial loads in both directions. DT arrangements are used for large axial loads in a single direction. - High precision
Precision class (P5 or above) arrangements are often used in the main spindles of machine tools. In these cases, a preload is applied based on operating conditions to adjust internal clearance. They also use a special fit.
Applications
- Pumps, compressors, screw chillers, elevator hoists
A back-to-back paired mounting of single-row angular contact ball bearings is turned into a bearing with a single inner ring and outer ring.
Double-row angular contact ball bearings are often used as fixed-end bearings as they can sustain axial loads in both directions and have the capacity to take moment loads.
These bearings feature pressed steel cages.
Features
- Compact design
An integrated back-to-back mounting of two single-row ACBBs in the form factor of a single inner ring and outer ring. - Support axial loads
Double-row ACBBs can take axial (thrust) loads in both directions.
Applications
- Compressors, press machines, automatic guided vehicles (AGVs), belt conveyors
Four-point-contact ball bearings feature an inner ring split into two pieces. Just one of these bearings can sustain significant axial loads in both directions.
A contact angle of 35° allows for high axial load capacity. This type is suited for carrying pure axial loads or combined loads where the axial load is high.
These bearings feature machined brass cages.
Features
- Easy to handle
The outer ring of these specialized single-row angular contact ball bearings can be separated from the two halves of the inner ring split along a plane perpendicular to the shaft center. - High axial load capacity
With a contact angle of 35°, four-point-contact bearings are well-suited for pure or combined loads where axial load is high. - Compact
A single bearing can be used to replace a face-to-face or back-to-back arrangement of bearings.
Applications
- Tractor transmissions, robot gearboxes, servomotors
FAQs
The thickness of the outer ring is different for the marked and unmarked sides of angular contact ball bearings. This is due to the contact angle between the outer ring and balls. Conversely, the thickness of the outer ring in deep groove ball bearings is equal on both sides. Additionally, ACBBs have 7xxx designations, while DGBBs have 6xxx designations.
Double-row ACBBs can take axial loads in both directions, but they have limited contact angle options. ACBB arrangements or multiple single-row ACBBs can only take axial load in one direction based on how they are combined. However, multiple-bearing options have no limits for contact angle, allowing for a custom selection to best match the ratio of radial load to axial load.
Additionally, the clearance and precision of ACBB arrangements is controlled as a set, creating a stable level of vibration/noise and rotational accuracy. However, using two single-row ACBBs that are controlled individually can cause significant variation in their resulting properties when combined.
As their name implies, the balls and outer ring in an ACBB make contact diagonally at the specifed contact angle. The contact angle affects the inclined contact made between the balls and outer ring, thereby affecting limiting speed and load capacity. The larger the contact angle, the higher the bearing's axial load capacity.
Catalogs
Search our full listing of catalogs for more details.
2D/3D CAD Data
Download 2D & 3D CAD model files and spec. sheets for NSK products through PARTcommunity.
This free service is provided by CADENAS GmbH.
