Gas Turbine Brush Seals

Lower Leakage, Greater Efficiency

Flexible brush seals, made from backward-angled alloy bristles, are immune to rubbing and maintain their original clearance longer than labyrinth seals alone, ensuring minimum compressor stage leakage and improved turbine efficiency.

Waukesha Bearings manufactures brush seals using the latest CNC technology, including precision wire EDM, which enables the holding of tight tolerances and dimensions.

No. 2 Bearing brush seal installed on a gas turbine
Gas turbine brush seal

Installation Locations

Industrial gas turbines have adopted the brush seal in three primary locations:

  • Bearing housing – to minimize leakage of high-pressure air at the #2 bearing housing seal and increase turbine performance
  • High pressure packing (HPP) sealing (compressor section inner barrel sealing) – to reduce clearances and cut leakage of high-pressure air into the turbine wheel space
  • Hot gas path interstage sealing – to reduce leakage between the diaphragm and turbine rotor into the stage 2 forward wheel space area, increasing effciency

Waukesha Bearings has provided hundreds of gas turbine brush seals for the most common GE Frames (the 9, 7, 6, and 5 models) and the Westinghouse 501 series.

Economical Seal Repair

Over time, as brush seals are subjected to multi-year duty cycles, replacement of the brush seals becomes a requirement.

Unlike conventional brush seals, the Waukesha Bearings modular brush seal assembly has three components: a bristle strip, a top plate, and a back plate.

Our modular assembly allows the replacement of the bristle strip without having to replace the entire seal. Recycling the seal plates and replacing the bristle strip make our brush seals reparable.

Worn gas turbine brush seal
Gas turbine brush seal repaired with replaceable bristle pack
Our unique modular assembly can reduce replacement cost by up to 30% when compared to the alternative approach of replacing the entire seal.
Frame 9 gas turbine brush seals


  • Reduce labyrinth bypass air flow by up to 50%
  • Increase turbine efficiency by up to 2%
  • Minimize shaft bowing and heating caused by rub-in features
  • Fit into existing labyrinths, eliminating the need for casing modifications
  • Extend time between seal replacements
  • Reduce future repair costs with patented modular assembly