PSS mechanical seal for rotary steam turbines.

Steam Turbine Rotary Union Seals

Why PSS?

Flexible Design: In addition to carrying standard sizing, a major advantage of the PSS Shaft Seal is its ability to be customized to adapt to an existing installation or design. Because of the ability to design the seal to fit most existing systems, engineers are unconstrained by seal size requirements. The time frame for custom seals is usually very low, 3 to 4 weeks.

Reliable & Durable: Due to its simple design the PSS Shaft Seal is durable and reliable, with a typical life span of 25,000 running hours. Under clean water conditions the seal can exceed 100,000+ running hours. The unique "float design" & flexibility of the PSS Shaft Seal allows for substantial axial movement of the shaft while still operating correctly.

Low maintenance & Ease of Installation: Minimal maintenance is required under normal working conditions with replacement parts readily available. Unlike other sealing systems, the seal does not wear the shaft or surrounding materials during operation which results in longer maintenance intervals.


All PSS mechanical seals have these certifications.

ABS Certified

Bureau Veritas Certified

RINA Certified


Materials: Rotor: 316L stainless steel
Carbon Stator: high density, resin impregnated carbon graphite
Bellow: Five ply cloth inlay with flurosilicone outer
Size: Can manufacture to any size and application
Operating Temperature: -25°F to +225°F (-31°C to +107°C)

PSS Seal Components

  1. Nitrile o-rings
  2. 316L stainless steel rotor
  3. Carbon graphite stator
  4. Nitrile or reinforced silicone bellow (depending on requirements)
  5. Clamp Jacket - rubber hose clamp protectors
  6. Hose clamps



What Is A PSS Shaft Seal?