Augmented Labyrinth Brush Seals

Reduce Clearances, Improve Efficiency

Augmenting labyrinth seals with brush seals, or installing complete replacement labyrinths with brush seals, is a simple and effective approach to reducing clearances and eliminating problems from shaft contact wear.

Augmented labyrinth brush seals
Augmented labyrinth brush seals

The Importance of Compliance

Over time, labyrinth seal clearances are compromised through erosion and material removal, which can stem from factors such as rotor-stator interaction (due to high imbalance loading) or transient excursions (due to asymmetric thermal growth between the rotor and casing). In addition, since labyrinth seals are rigid geometry seals and are not capable of bending to accommodate rotor excursions, design clearances are engineered to account for all phenomena affecting clearance closures in the machine.

The brush seal’s compliancy – its ability to bend – allows sealing clearances to be significantly reduced, thus increasing machine efficiency and power.

Retrofit Capability

The low profile of the Bearings Plus bristle strip provides a simple and cost-effective integration with an existing labyrinth seal. We typically utilize the existing labyrinth blades and teeth to create a back plate. Wire EDM technology ensures precise and reliable clearances for the labyrinth’s augmentation to accept the brush seal.

Bearings Plus has upgraded a large number of equipment with augmented labyrinth seals, including process steam turbines, centrifugal compressors, and turboexpanders.

Augmented labyrinth brush seal


  • Reduce initial leakage by 50% compared to straight labyrinth seals, or by 30% compared to interlocking labyrinth seals
  • Eliminate steam leaks and the safety hazards associated with high temperatures and toxic gases
  • Reduce condenser capacity and space requirements in new steam turbines
  • Require less axial space than labyrinths
  • Easily installed and field serviceable in a variety of sealing environments
  • Allow a “wear-in” to minimal clearance through flexible sealing mechanism
  • Standard components for cost-effectiveness and timely shipment
  • Can be field fitted to undersized shafts, eliminating the need to weld or coat worn rotors

Related Products & Services

Brush seal contact analysis heat map

Rotordynamic Analysis

Rotordynamic analysis evaluates bearing and seal characteristics simultaneously to better understand the independent effect of each component.
Thermoplastic labyrinth seal

Labyrinth Seals

Bearings Plus provides custom-engineered labyrinth seals in conventional metals or advanced thermoplastics.
TAMSEAL pocketed damper seal

Pocketed Damper Seals

The pocketed damper seal prevents gas swirl and provides 50 to 100 times more damping than a conventional labyrinth seal.