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Silicone is a synthetic elastomer known for its excellent flexibility, thermal stability, and biocompatibility, making it a common choice for valve seals, diaphragms, gaskets, and O-rings in food, pharmaceutical, medical, and sanitary applications. It is an excellent elastomer for valves requiring high flexibility and sealing performance across a wide temperature range.

Properties

Properties

  • Wide Temperature Range – Retains flexibility from -60°C to +200°C (-76°F to +392°F), with some high-temp grades reaching +250°C (482°F).
  • Excellent Flexibility & Compression Set Resistance – Provides reliable sealing in static and dynamic valve applications.
  • Food & Pharmaceutical Safe – Many silicone grades are FDA-compliant and meet USP Class VI for sanitary and clean service.
  • Resistant to Aging & UV/Ozone – Excellent weatherability and resistance to ozone, oxygen, and sunlight.
  • Low Toxicity & Non-Tainting – Suitable for potable water, food contact, and medical devices.

Silicone vs. Other Elastomers in Valves
• More flexible at extreme cold than FKM, EPDM, or NBR.
• Better suited for food-grade and medical applications than many industrial elastomers.
• Less chemically resistant to oils and fuels compared to FKM (Viton®).

Limitations

Limitations

  • Poor Resistance to Oils & Fuels – Swells and degrades in hydrocarbons, oils, and many solvents (better alternatives would be NBR or FKM).
  • Moderate Tear & Abrasion Resistance – Softer and less abrasion-resistant compared to urethane or EPDM in harsh environments.
  • Lower Mechanical Strength – Not suitable for high-pressure sealing without reinforcement.

Common Applications

Common Applications

Food & Beverage Valves – Used in butterfly, diaphragm, and sanitary valves for clean and hygienic processes.
Pharmaceutical & Biotech Valves – Common in aseptic valves and cleanroom environments requiring non-reactive sealing materials.
Medical Valves – Applied in life science and healthcare systems for bio-compatible sealing.
General Utility Valves – Used in HVAC and water handling systems requiring wide temperature flexibility.