SealSpec / Custom gaskets
Custom gasket materials compared
Ten common custom-gasket material families, side by side. Pick based on temperature, media, outdoor exposure and how much closure force your design has, then open the builder to spec the part.
Know your geometry?Draw the gasket, pick a material and export a DXF + spec sheet.
Open the spec builder →| Material | Typical temp. | Strengths | Watch out for | Common uses |
|---|---|---|---|---|
| Silicone sponge VMQ, closed-cell | -75 to 400 °F | Very wide temperature range Low compression set (good long-term sealing) | Poor tear and abrasion resistance Not for petroleum oils and fuels | Electrical and lighting enclosures, HVAC and appliance doors, EV battery covers |
| EPDM sponge EPDM, closed-cell | -40 to 250 °F | Excellent weather, UV and ozone resistance Good water and steam resistance | Not for petroleum oils, fuels or solvents Higher compression set than silicone | Outdoor enclosures and cabinets, HVAC panels, Automotive body seals |
| Neoprene sponge CR, closed-cell | -40 to 212 °F | Balanced oil, weather and flame resistance Good general-purpose sponge | Not for strong acids or ketones Weathering is weaker than EPDM | Industrial enclosures, Vibration and dust seals, Transportation |
| Microcellular urethane foam (PORON-type) Polyurethane, microcellular | -40 to 194 °F (typical) | Very low compression set for a foam Consistent compression force | Limited high-temperature use Limited hydrolysis resistance in hot, wet service; check grade | Electronics and display gaskets, Battery cell cushioning, Dust and light seals |
| Solid silicone rubber VMQ | -65 to 450 °F | Wide temperature range Weather, ozone and UV resistance | Low tear strength Not for petroleum oils, fuels or steam over long periods | Food and medical equipment, Heat-exposed seals, Lighting |
| Solid EPDM rubber EPDM | -40 to 275 °F | Water, steam, glycol and brake-fluid resistance Excellent outdoor aging | Swells badly in petroleum oils and fuels | Water and HVAC systems, Outdoor equipment, Potable water (with certified grades) |
| Nitrile (Buna-N) rubber NBR | -30 to 250 °F | Good resistance to petroleum oils, fuels and hydraulic fluids Good abrasion resistance | Poor ozone and UV resistance outdoors Not for ketones, brake fluid or strong acids | Engine and gearbox covers, Hydraulic equipment, Fuel-system flanges |
| FKM fluoroelastomer (Viton-type) FKM | -15 to 400 °F | Excellent fuel, oil and chemical resistance High temperature capability | High cost Poor in ketones, some amines and hot water/steam for standard grades | Fuel and chemical handling, Semiconductor and process equipment, High-heat engine seals |
| PTFE (solid, filled and expanded) PTFE | -450 to 500 °F | Near-universal chemical resistance Very wide temperature range | Cold flow / creep under bolt load: filled or expanded grades reduce it Needs higher seating stress than rubber | Chemical process flanges, Pharma and food equipment, Valves and pumps |
| Compressed non-asbestos fiber sheet Aramid/fiber + NBR or SBR binder | up to ~700 °F short-term, grade-dependent | Holds bolt load well in flanged joints Steam, water, oil and hydrocarbon service by grade | Temperature × pressure limits depend on grade: check the P×T chart Not a low-closure-force seal | Pipe flanges, Pumps and compressors, Industrial covers |
Choosing quickly
- Low closure force or uneven surfaces (sheet-metal enclosures, doors): closed-cell sponge or microcellular urethane.
- Outdoor, water, UV: EPDM (sponge or solid), or silicone for wider temperature.
- Oils and fuels: nitrile, or FKM for heat and chemical range.
- Bolted pipe flanges: compressed fiber sheet or PTFE, sized to ASME B16.21.
- Aggressive chemicals: PTFE, or FKM where rubber elasticity is needed.
General engineering guidance. Confirm grade-specific data and test in your application.