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Mechanical face seals are common in commercial and industrial applications to prevent the escape of process fluids, including liquid and/or gas, and particulates from entering the process. Carbon face seals are often used when a rotating shaft passes through a housing. The carbon/graphite materials used in mechanical face seal design will vary by application. One of the boundary conditions some mechanical seals face is a lack of lubrication in the contacting interface between the sealing faces.

Using state-of-the-art design tools, Stein has developed innovative face-seal technologies that prevent the damage caused by dry-running, face-to-face contact.

These custom design features in the mating faces offer many benefits over traditional face seal technology. As the seal ring rotates, buffer fluid, air, oil or gas, is forced between the sealing face gap. As the pressure increases between the primary sealing elements, the faces separate or lift, preventing the sealing faces from direct contact.

Advanced spiral-groove designs
Hydrodynamic lift-off geometry
Inward and outward pumping designs
Bi- and uni-directional non-contacting lift-off seals

Types of Face Seals:

  • Contacting (rubbing)
  • Non-contacting (film riding)
  • Hydrodynamic
  • Hydrostatic

Key face-seal features:

  • Low-heat generation
  • Low friction
  • Reduced wear
  • Efficiently manage radial shaft movements while maintaining low-leakage rates.
  • Leakage rates remain constant over the life of the seal, ensuring consistent, reliable sealing.
  • Pressure-balanced for higher delta pressure capability and decreased heat generation for long seal life.
  • Designed to tolerate sudden pressure reversals, such as in chemical gas applications.

Common applications include gearboxes, aircraft engine main shafts, compressors, pumps, and propulsion systems. Quickly and easily installed or removed, a Stein face seal can normally be maintained or replaced without interrupting production or incurring additional labor costs. Configurations include standard single-ring, back-to-back, face-to-face, or tandem arrangements.

Stein Face Seals at Work

Today, Stein Seal face seals can be found hard at work worldwide. They are integral to gas turbine engines and oil refineries, where they are used in alkylation, flare gas recovery, and the processing of crude oil and wet gas. Also, in the petrochemical industry, they are essential to applications involving polypropylene, ethylene, styrene, propane, isobutane, carbon monoxide, methanol, synth gas, ammonia refrigeration, and others.