Squeeze film dampers are used to shift critical speeds and/or to increase the dynamic stability of a rotor/bearing system.
One of the key features of a squeeze film damper is the introduction of support flexibility and damping in the bearing/support structure. This translates to lower transmitted forces and longer bearing life, particularly for machinery designed to operate at supercritical speeds.
Bearings Plus offers a sophisticated integral squeeze film damper – our ISFD® technology – to provide a highly accurate yet simple solution for new and retrofit installations requiring squeeze film dampers.
The ISFD design, optimized with finite element methods and manufactured by wire EDM, provides precisely controlled stiffness and damping. It maximizes energy dissipation at the bearing location and significantly improves system stability.
This unique damper design provides:
- Precise stiffness and damping to match rotordynamic requirements
- Constant stiffness and damping over a wide range of motion
- Minimal space requirements
- Shaft-centering ability
Unlike O-ring dampers, the ISFD design takes high radial loads and offers linear stiffness unaffected by temperature or age. Unlike squirrel cage dampers, the ISFD maintains parallelism between the damper journal and housing.
ISFD Design Versatility
ISFD technology can be integrated into a wide range of journal bearing styles:
- Flexure Pivot® bearings
- Rocker back bearings
- Ball and socket bearings
- Sleeve bearings
- Elastomer bearings
- Rolling element bearings
In every instance, the damper is optimized for the specific application through rotordynamic analysis, significantly improving system stability and offering accurate predictability.
The space-saving design allows for drop-in replacement without modifications to the bearing housing.
Split configuration is available for compliance with API specifications dictating split bearings configuration.
ISFD Technology with a Ball Bearing
ISFD Technology with Elastomer
- Integrally geared compressors
- Centrifugal compressors
- Steam turbines
- Gas turbines
- Radial turbines
- Supercritical CO2 power turbines
- Overhung process equipment
Related Case Studies
Long-term Solution to Vibrations
Over a 13-year span, a major South American oil company’s maintenance department fought recurring high vibrations in three gas reinjection compressor trains. Based on a thorough analysis of the compressors and an inspection of damaged components, Bearings Plus proposed a two-part solution.
Achieving Full Power Output
For a power generation customer in Scandinavia, Doosan Škoda Power engineered a 46 MW steam turbine as part of a combined cycle system. When high subsynchronous vibrations forced a trip in turbine operation at just 27 MW versus the rated 46 MW, Bearings Plus stepped in with a damper solution.
At the Dow Chemical Company operation in Deer Park, Texas, product buildup on an overhung blower was leading to mass imbalance and high synchronous vibrations that could cause catastrophic failure. The company brought in Bearings Plus to provide a greater stability margin and reduce the sensitivity to imbalance.