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Urethane (Polyurethane) is a versatile elastomeric material commonly used in valve seats, liners, seals, and diaphragms, especially where abrasion resistance, impact resistance, and flexibility are key requirements. It is popular in industries dealing with abrasive materials, mining operations, and bulk handling.

Properties

Properties

  • Outstanding Abrasion & Impact Resistance – Performs exceptionally well in high-wear environments, such as slurry and mining applications.
  • Good Tear & Cut Resistance – Durable under mechanical stress and dynamic loads.
  • High Flexibility – Maintains elasticity across a wide temperature range, offering effective sealing in knife gate, pinch, and butterfly valves.
  • Moderate Chemical Resistance – Resists oils, greases, and some hydrocarbons, depending on formulation (e.g., ester- or ether-based urethanes).
  • Shock Absorption – Excellent ability to dampen vibration and absorb mechanical impact in valve seats and liners.

Urethane vs. Other Elastomers in Valves
• Superior abrasion resistance compared to EPDM or NBR.
• Less chemically resistant than FKM or PTFE in aggressive chemical service.

Limitations

Limitations

  • Limited Chemical Resistance to Acids & Solvents – Degrades in strong acids, ketones, and chlorinated solvents.
  • Temperature Limitations – Typically rated for continuous service up to 80°C to 90°C (176°F to 194°F), though some specialized grades can tolerate higher.
  • Hydrolysis Sensitivity – Polyester-based urethanes can degrade over time in humid or submerged environments (ether-based versions improve this).

Common Applications

Common Applications

Slurry & Mining Valves – Used in knife gate valves, pinch valves, and slurry control valves exposed to abrasive media like sand, gravel, and slurry.
Water & Wastewater Valves – Applied in check valves and plug valves handling solids-laden fluids.
Pulp & Paper Valves – Protects against abrasion in stock handling and pulp processing systems.
Bulk Material Handling Valves – Used in valves controlling powders and granular materials.