Below are typical materials, each with a summary of their features and how they can be processed.
| Material | Key characteristics | Typical suitability for punching / CNC / waterjet / laser |
|---|---|---|
| Elastomer / Rubber sheets (e.g., Nitrile (NBR), EPDM, Neoprene, Silicone, Viton®/FKM) | Flexible, resilient, good compressibility, moderate chemical resistance (depending on grade), good for low-to-medium pressure. For example, EPDM remains flexible at low temperatures and resists weather/ozone. | Very suitable for punching or die-cutting (large volumes, simple shapes). CNC knife or router for custom shapes. Waterjet is good too (especially for thicker or softer materials) because minimal heat. A laser may be used for thinner sheets, but caution: some elastomers may melt or char under laser heat. |
| PTFE sheet (polytetrafluoroethylene, expanded PTFE) | Excellent chemical inertness, wide temperature range (especially down to cryogenic, up to moderate/high temps depending on fill), low friction, good for corrosive media. But relatively “soft” (in terms of mechanical strength) and may creep under load. | Punching/die-cutting is common for simpler shapes. CNC knife or routing may work. Waterjet is very suitable for thicker sheets and complex shapes (cold cutting). Laser cutting is possible for very thin PTFE, but caution: lasers may cause fumes, edge burn, or degrade PTFE (fluorine gas risk), so many providers caution against using lasers for PTFE. |
| Flexible Graphite Sheet (graphite foil/laminate) | High temperature resistance (depending on atmosphere), excellent conformability (fills flange irregularities), good chemical resistance, low creep (depending on grade), high compressibility and recovery. Works in harsh environments. | Because of its sheet form, it can be punched or die-cut for high volumes. CNC cutting (knife, router) works. Waterjet is excellent (cold cut avoids heat damage, and the material is amenable). Laser cutting may be used, but edge quality, far-edge thermal effect, and handling of the material need qualification; thicker sheets might pose challenges. |
| Non‐Metallic Sheet Composite Materials (compressed non-asbestos fibre, mica/vermiculite mineral sheets, cork-rubber composite, felt, ceramic fibre, etc.) | These are composite sheets often used in general service gaskets: moderate pressure/temperature, sometimes budget-sensitive. Some have good chemical/temperature resistance depending on composition. | Punching/die-cut is the typical method (especially for simpler, high-volume shapes). CNC cutting works for custom shapes or smaller runs. Waterjet works well for thicker or more difficult to cut materials (because minimal heat). Laser may be limited due to heat sensitivity, char or edge issues in some composites. |
| Metallic & Semi-Metallic Gasket Materials (e.g., sheet metal gaskets, foil/mesh reinforced graphite, Kammprofile, spiral wound, metal jacketed) | Used for high-pressure, high-temperature, or critical sealing applications. Semi-metallic means non-metal filler + metal reinforcement. These materials tend to require stronger flanges, higher bolt loads, etc. | Processing tends to be more robust: Waterjet cutting is excellent for metals and semi‐metals (cold cut, no heat-affected zone). Laser cutting works for thinner sheet metals but might introduce heat affected zone or distortions. Punching (with appropriate tooling) feasible for simpler shapes/volumes. CNC routing less common for thicker metals; CNC machining may be used. For high volume thin sheet metal gaskets, die |
