Camlock Gasket Selection Guide: EPDM, NBR, Viton or PTFE?
The gasket is the only part of a camlock that actually seals. The body holds the parts together; the gasket stops the leak. Pick the wrong compound and the coupling fails even though the metalwork is perfect.
Gasket compound quick table
| Compound | Media | Temperature range | Cost | Notes |
|---|---|---|---|---|
| EPDM | Water, steam, mild chemicals, brake fluid | -40°C to 120°C (-40°F to 248°F) | $ | The default for water and general duty. Poor resistance to oils, fuels, solvents |
| NBR (Buna-N) | Oil, fuel, hydraulic fluid, lubricants | -30°C to 100°C (-22°F to 212°F) | $ | The default for fuel and oil transfer |
| Viton (FKM) | Aggressive chemicals, acids, solvents, high temperature | -20°C to 200°C (-4°F to 392°F) | $$$ | Broad chemical resistance; the premium choice for chemical lines |
| PTFE | Nearly everything, high temperature | -200°C to 260°C (-328°F to 500°F) | $$$ | Inert, but harder — seals best with an outer elastomer ring or careful torquing |
How to choose
- Identify the media. Water → EPDM. Fuel, diesel, oil → NBR. Solvents, acids, aggressive chemicals → Viton or PTFE. Steam → EPDM (steam) or PTFE (hot process).
- Check temperature. A gasket that handles the chemical but not the temperature is still a failure. EPDM handles hot water and steam; NBR softens above ~100°C; Viton handles 200°C.
- Check the other components. The gasket must suit the coupling material too — a polypropylene body with a Viton gasket carrying a chemical that attacks polypropylene still fails. Match the whole assembly to the media.
- Food contact? Specify food-grade (FDA/NSF) gaskets for food and beverage lines. Standard EPDM and NBR compounds are not all food-safe.
The cost trap
Viton and PTFE gaskets cost several times more than EPDM or NBR — worth it on a chemical line, wasted on a water line. Conversely, running EPDM on a fuel line saves a few cents per gasket and costs a tank of product per leak. The gasket is the cheapest part of the connection and the one that decides whether it works.
How to change a camlock gasket
- Remove the old gasket from the machined groove in the coupler face — it usually peels out; a pick helps if it is perished.
- Clean the groove — grit under the new gasket re-introduces the leak.
- Seat the new gasket evenly in the groove, flat and untwisted.
- Re-connect and pressure-test. A gasket change takes under a minute on an open line.
When to replace
- Flattened, cracked or hardened gaskets (feel: it should stay flexible)
- After heavy chemical exposure, even if it looks fine
- After the coupling has been apart several times
- Gaskets are consumables. Stock spares for every size you run.
Not sure which compound your line needs? Send the media, temperature and pressure and we will confirm the gasket and coupling combination.