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Single Cartridge with flush S1

The S1 Single Cartridge has become the cornerstone product for Apex Sealing. Since it’s introduction, our goal has been to offer a rugged, well designed stationary multiple spring cartridge at a price that aggressively competes with the older mass produced rotating spring designs.

The success of the S1 has far surpassed our expectations. The seal has allowed both Apex and it’s customers to reach new plateaus of durability, end user satisfaction and profitability.

Single Cartridge with Flush 


Features & Benefits

  • One of the industry's most aggressively priced
    stationary cartridges

  • Easy cartridge installation

  • Stationary multiple spring design

  • Springs isolated from product

  • Rugged face design

  • Identical seal face shapes make repairs easy and

  • Hydraulically balanced design

  • Handles pressure reversals and vacuum

  • Flush connection standard

  • Vent and Drain connections available upon request

  • Big Bore gland alternatives

  • Interchangeable parts with D2 dual cartridges

  • User friendly setting clips

  • Confined gland gaskets

Standard Materials of Construction


  • Carbon / Silicon Carbide

  • Silicon Carbide / Silicon Carbide
    (Note: Tungsten Carbide and Antimony Carbon also available)


  • Viton*, Buna, PTFE, Neoprene, EPR, Kalrez*,
    AFLAS*, Chemraz*


  • 304, 316, Monel, Alloy 20, Hast B+ C*

Operating Limits

  • Pressure: Up to 250 PSI/17 Bar

  • Temperature: -40° to 425° F, -40° to 235 ° Celsius*

S1 drawing
S1 gland plate drawing
S1 dimensions

*Registered Trademarks: Apex recognizes all trademark names as the property of their owners. 

Hastelloy® - Haynes / Viton® - DuPont / Kalrez® - DuPont / AFLAS® - ASHAI Glass / Chemraz® - Greene Tweed

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