1) Elastomers (Rubber)
NBR (Nitrile) EPDM FKM / Viton
Temperature
-40°C to 150°C (depends on type)
Fluids
Water, oils, fuels, mild acids/bases
Standards
ASTM D2000, ISO 3302
Valve Seals & Material Classification
Release time:2025.09.02
Valve Seals • Material Classification
Valve Seal Material Classification & Properties
Choosing the right seal material is critical to valve performance, reliability, and service life. This guide outlines the main categories of valve seal materials, their typical applications, temperature and chemical compatibility, and common standards.
What You'll Learn
Common seal materials: elastomers, PTFE, metal, graphite, and composite.
Material selection based on temperature, pressure, and fluid compatibility.
Regional and international standards for sealing materials (ASTM, EN, JIS, ISO).
Applicable Valves
Gate, Globe, Ball, Butterfly, Check
Gate, Globe, Ball, Butterfly, Check
Inspection Focus
Hardness, Chemical Resistance, Temperature, Wear
Hardness, Chemical Resistance, Temperature, Wear
2) PTFE / Teflon
Virgin PTFE Filled PTFE (Glass, Carbon, MoS2)
Temperature
-200°C to 260°C
Fluids
Most chemicals, aggressive media, steam
Standards
ASTM D4894, EN 607
3) Metal Seals
Stainless Steel Copper Inconel / Monel
Temperature
Up to 600°C+
Applications
High pressure, high temperature, or vacuum valves
Standards
ASME B16.20, EN 12516
4) Graphite
Flexible Graphite Spiral Wound Gaskets
Temperature
-200°C to 450°C
Fluids
Steam, acids, caustics, high temp oils
Standards
EN 1514, ASTM F104
5) Composite / Hybrid Seals
PTFE + Elastomer Graphite + Metal
Applications
Enhanced chemical resistance + spring loading for tight sealing
Standards
ISO 3601, EN 13555
Bottom Line: Selecting the correct seal material is key to valve performance, longevity, and leak-free operation. Consider temperature, pressure, fluid type, and standards when making your selection.
