Liquid Nitrogen Resistant O-Rings
Compatibility ratings for 7 O-ring materials in Liquid Nitrogen service
Liquid Nitrogen (Cryogenics) compatibility with the seven most common O-ring elastomers, rated on the standard A/B/C/D scale: A = excellent, B = good, C = fair, D = not recommended. This data also appears in our interactive chemical compatibility chart and is available machine-readable at /api/chemicals.json.
| Material | Rating | Guidance |
|---|---|---|
| NBR | D | not recommended — rapid degradation expected |
| FKM | D | not recommended — rapid degradation expected |
| EPDM | D | not recommended — rapid degradation expected |
| VMQ | C | fair — conditional use, verify with testing |
| PTFE | A | excellent — recommended for continuous service |
| FFKM | A | excellent — recommended for continuous service |
| HNBR | C | fair — conditional use, verify with testing |
Why These Ratings
- PTFE (A) — documented strengths include “Virtually all chemicals.”
- FFKM (A) — documented strengths include “Virtually all chemicals except molten alkali metals.”
CryogenicsService: Concentration & Temperature Notes
Cryogenic service is a temperature problem more than a chemistry problem: PTFE and FFKM retain their properties at cryogenic temperatures, while standard elastomers pass their glass-transition point and turn brittle. Ratings here assume static sealing at temperature — thermal cycling between ambient and cryogenic is harder than steady state. Verify groove design across the full thermal envelope.
Recommended
- PTFE O-rings (A)
- FFKM O-rings (A)
Use With Caution
- VMQ O-rings (C)
- HNBR O-rings (C)
Avoid
- NBR (D)
- FKM (D)
- EPDM (D)
Related Chemicals (Cryogenics)
Frequently Asked Questions
Is Liquid Nitrogen compatible with FKM (Viton) O-rings?
FKM is rated D for Liquid Nitrogen: not recommended — rapid degradation expected. Ratings are general guidelines; concentration, temperature and exposure time all affect real-world compatibility, so validate critical applications with ASTM D471 immersion testing.
Is Liquid Nitrogen compatible with NBR (nitrile) O-rings?
NBR is rated D for Liquid Nitrogen: not recommended — rapid degradation expected. NBR is the lowest-cost elastomer, so when it earns an A or B rating it is usually the economical default; when it rates C or D, do not substitute it for a higher-rated material to save cost.
Can I use PTFE O-rings with Liquid Nitrogen?
PTFE is rated A for Liquid Nitrogen: excellent — recommended for continuous service. Remember that PTFE has no elastic memory — in demanding service it needs spring energization or an elastomer core (FEP/PFA encapsulation) to maintain sealing force.
What is the best O-ring material for Liquid Nitrogen?
PTFE, FFKM are rated A (excellent) for Liquid Nitrogen in our compatibility data and are the recommended starting point for material selection. Final selection should also account for operating temperature, pressure and whether the seal is static or dynamic.
Can I use EPDM O-rings with Liquid Nitrogen?
EPDM is rated D for Liquid Nitrogen: not recommended — rapid degradation expected. Always confirm the specific fluid concentration and temperature before specifying EPDM for this service.
Need O-Rings for Liquid Nitrogen Service?
Send us your fluid, concentration and temperature — our engineers will confirm the right compound. MOQ 1 piece.