Thermoplastic Labyrinth Seals For Centrifugal Compressors.

Tutorialpg. 113-126For over 15 years now, the efficiency and reliability of centrifugal compressors have been enhanced by the application of thermoplastic materials to the eye, shaft, and balance piston labyrinth seals. Traditionally these seals have been manufactured from metallic materials and have required relatively large clearance for reliability reasons. By upgrading to carefully selected engineered thermoplastics, the clearances can be reduced without sacrificing reliability. This results in increased compressor efficiency and the added benefit of easier installation. This tutorial will review the design and application of thermoplastic seals as used in centrifugal compressors. The tutorial will not cover in any detail abradable seals (such as babbitt or lead lined), reduced cross-coupling seals, or “other” seals (such as honeycomb, brush, carbon ring, dry gas, etc.)