DESIGN GUIDE
Tapered AIR BEARINGS Design and Installation Guide
This guide provides engineering best practices for the design, preload configuration, and installation of OAV Tapered Air Bearings. Follow these recommendations to achieve optimal performance, stiffness, and accuracy.
01
Component Overview
The OAV Tapered Air Bearing assembly consists of two main components: the inner assembly and the outer cage. The outer cage interfaces with the housing while the inner assembly interfaces with the shaft/spindle.
Inner Assembly
Shaft
Outer Cage
Air may be supplied either through the shaft cross-hole or through the outer cage inlet depending on configuration type.
Design & Installation Guides
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Tapered Air Bearings
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Linear Guide Air Bearings
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02
Configuration Types
OAV Tapered Air Bearings are available in two configuration types depending on which component rotates and how air is supplied.
M Series - Inner Spin
The inner assembly rotates while the outer cage remains stationary.
Rotating Member
Inner Assembly
Air Supply
Inlet from outer cage (external)
Typical Use
Applications where the shaft rotates
MX Series - Outer-Cage Spin
The outer cage rotates while the inner assembly remains stationary.
Rotating Member
Outer Cage
Air Supply
Through shaft cross-hole (internal)
Typical Use
Spindle or structures where outer rotation is needed
03
Mounting Methods
OAV Tapered Air Bearings are typically mounted using a light press fit between the outer cage and the housing while maintaining proper shaft alignment through the inner assembly. When multiple bearings are used, spacers may be inserted between assemblies to improve stability, alignment, and overall fit. Proper alignment during installation is critical to achieving optimal stiffness, accuracy, and operating performance.​
Single Bearing
(Press Fit)
Light press fit between the outer cage and housing while maintaining proper shaft alignment through the inner assembly. Suitable for compact systems and standard precision applications. For customer-designed housings, contact OAV for recommended bore sizing and tolerances.
Multiple Bearings
(With Spacers)
Multiple tapered air bearings may be mounted in series using spacers to improve alignment, stiffness, and load distribution. Spacer configurations are commonly used in higher-load or higher-precision applications where additional system stability is required.
04
Recommended Gap & Air Supply
RECOMMENDED GAP
The gap between the two components is negligible. The recommended gap is 4-5 microns.
AIR SUPPLY OPTIONS
To achieve this gap during installation, the two main components will be placed up against the frictionless surface of the tapered air bearing.
Internal Air Supply Through Cross-Hole
External Air Supply Through Outer-Cage
Once the air supply is turned on, a small gap will be created. During installation apply 30 PSI air pressure to ensure free movement and proper gap creation.
05
Key Design Considerations
PRELOAD SELECTION
Choose the appropriate preload configuration based on stiffness, load capacity, and accuracy requirements.
PARALLELISM
Maintain parallelism between bearing mounting surfaces for improved performance.
LOAD DISTRIBUTION
Distribute loads evenly across opposite bearing pairs or multiple bearings.
ENVIRONMENT
Ensure clean, dry air supply to prevent contamination and maintain consistent performance.