KOSA Valve · Application Engineering
Sanitary Valve Material Compatibility Guide
Choose valve materials by the fluid, temperature and cleanability requirement: 316L stainless for most hygienic duty, PTFE for aggressive chemicals, EPDM/FKM for seals. Compare body and elastomer compatibility before specifying.
Key Takeaways
- 316L stainless steel is the default hygienic valve body for most food, dairy and pharma duty.
- PTFE (and PFA-lined) suits aggressive chemicals and wide temperature range.
- Elastomer seals — EPDM, FKM, Silicone — decide chemical and temperature limits more than the metal body.
- Match the elastomer to the CIP regime: EPDM resists steam/CIP; FKM resists oils/solvents but ages faster in steam.
- Always confirm compatibility with the exact fluid and concentration, not the family name.
Body materials
The valve body sets the pressure, temperature and corrosion baseline; the elastomer seal usually sets the chemical limit.
| Material | Strengths | Watch-outs | Typical use |
|---|---|---|---|
| 316L SS | Corrosion-resistant, weldable, hygienic | Not for strong halides at high temp | Default food/dairy/pharma |
| 304 SS | Lower cost | Less molybdenum, weaker CIP resistance | Non-critical, dry or mild duty |
| PTFE / PFA-lined | Excellent chemical resistance, wide temp range | Higher cost, less mechanical robustness | Aggressive chemicals, acids |
Elastomer seals compared
Seals see the fluid directly and often fail first. Pick the elastomer for the CIP and product chemistry, not the body metal.
| Elastomer | Temperature | Chemical fit | Notes |
|---|---|---|---|
| EPDM | −40 to ~150 °C | Steam, CIP, polar fluids | Standard hygienic seal |
| FKM (Viton) | −20 to ~200 °C | Oils, solvents, some acids | Poor in steam/amines |
| Silicone | −60 to ~200 °C | Pharma-friendly, clean | Lower abrasion resistance |
Selection checklist
1. What is the exact fluid and concentration?
Compatibility depends on concentration and temperature, not the chemical family name alone.
2. What is the CIP / SIP regime?
Steam and oxidising CIP favour EPDM; solvent or oil duty favours FKM.
3. What temperature and pressure?
Confirm both body rating and elastomer temperature limit.
Compatibility above is general guidance. Always verify against the specific chemical, concentration and temperature, and request material certs for validated lines.
Need a specification for your line?
Send your fluid, flow and hygiene class — we return a documented recommendation.
Contact KOSA KosavalveFrequently asked questions
What is the default material for hygienic valves?
316L stainless steel is the default body material for most food, dairy and pharmaceutical duty because of its corrosion resistance, weldability and hygienic surface. 304 is a lower-cost alternative for non-critical service.
Which seal elastomer should I choose?
EPDM is the standard hygienic seal for steam and CIP duty; FKM resists oils and solvents but ages faster in steam; silicone is pharma-friendly at wide temperature. The elastomer usually sets the chemical limit, not the metal body.
When is PTFE or PFA lining used?
PTFE or PFA-lined valves are specified for aggressive chemicals and acids, or where a very wide temperature range is needed, at higher cost than stainless bodies.
How do I confirm compatibility?
Verify against the exact fluid, concentration and temperature — not just the chemical family — and request material certificates for validated lines.