Foil Air & Gas Bearings
Foil bearings are self-generating, compliant hydrodynamics bearings.
Their compliant foils conform to the size and shape of the mating rotating shaft. During operation, the rotating shaft of an oil-free high speed turbomachine is supported on a thin, self generated film of high pressure air or gas. A pair of foil journal bearings provide radial support, and a pair of foil thrust bearings absorb axial load. Foil air/gas bearings have demonstrated high load carrying capacity, good stability characteristics, and extraordinary durability.
A typical foil journal bearing includes one or more top foils, backed by corrugated foils that provide a small preload between the shaft and top foils. For low friction during lift-off and touch-down, the foils are coated with a solid film lubricant. During lift-off and operation, air/gas is drawn between the shaft and the bearing and locally compressed; hydrodynamic action causes the shaft to lift off and float on a cushion of air/gas.
Foil thrust bearings work much the same way. Hydrodynamic action creates a high pressure air/gas film between a rotating thrust runner and coated top foil pads, backed by corrugated foil pads and arranged on a thin, circular plate. Thrust bearings absorb thrust load during startup and operation.
The spring rate of the corrugated segments accommodates shaft expansion, shaft excursion and housing misalignment. The corrugated foils provide compliance and suppress whirl during operation, and they provide a flow path for a small amount of cooling air/gas.
R&D Dynamics has developed foil journal bearings with diameters as small as 0.375 inches and as large as 6 inches, foil thrust bearings with diameters as small as 0.80 inches and as large as 9.00 inches.
Advantages of Foil Air/Gas Bearings:
No Oil Contamination
No Scheduled Maintenance
Higher Speed Capability
High Load Capacity
Higher Vibration and Shock Load Capacity
Higher and Lower Temperature Tolerance (40K to 2500K)
Any process fluid an be used
Increased Machine Performance and Durability
Lower Lifecycle Cost
- Foil Air/Gas Bearing Technology ~ An Overview
- Foil Air Bearing Cleared to Land ~ Mechanical Engineering Magazine
- Foil Air/Gas Bearings
- Motor Driven Blowers and Compressors
- Vapor Cycle Compressors
- Organic Rankine Cycle
- FAA Approved PMA Parts
- Hartford Aero Maintenance
With 24/7 customer support services, R&D Dynamics guarantees immediate response. We will stay focused on your needs until the problem is resolved.
Call (860) 726-1204