Pharmaceutical O-Rings for CIP and SIP
USP Class VI silicone and peroxide-cured EPDM for clean-in-place, steam-in-place and bioreactor sealing.
Pharmaceutical manufacturing demands seals that can withstand repeated Clean-in-Place (CIP) and Steam-in-Place (SIP) cycles without degrading, extracting contaminants, or harbouring bacteria. O-rings in bioreactors, filling machines, WFI systems and freeze dryers must be biocompatible, thermally stable and resistant to aggressive cleaning chemistry. We supply platinum-cured VMQ (Silicone) and peroxide-cured EPDM O-rings certified to USP Class VI and FDA 21 CFR 177.2600. Both materials tolerate saturated steam to 134°C and repeated thermal cycling. Our pharmaceutical grades are formulated for low extractables, minimal protein binding, and long service life in validated equipment.
Application Requirements
Recommended Materials
VMQ (Silicone)
Bioreactors, filling needles, freeze dryers, medical tubing
Platinum-cured USP Class VI
Design Tips
- 1.Use platinum-cured silicone rather than sulfur-cured for the lowest extractables
- 2.Specify peroxide-cured EPDM for hot water and steam service above 120°C
- 3.Design grooves with 20–25% compression to compensate for thermal expansion during SIP
- 4.Avoid NBR and FKM in repeated steam service unless specifically validated
- 5.Use blue or white coloured seals for visual detection during assembly and inspection
Common Sizes
| Size | Typical Use |
|---|---|
| Tri-Clamp ferrule seals: 1/2" to 4" | standard sanitary sizes |
| AS568-006 to AS568-050 | small instrument seals |
| AS568-110 to AS568-178 | valve and pump seals |
| Custom sizes for single-use bioreactor housings | General application |
Frequently Asked Questions
What is USP Class VI?
USP Class VI is a United States Pharmacopeia standard for plastics and elastomers used in medical and pharmaceutical applications. It involves extraction testing and biological reactivity testing to confirm safety for human contact.
Can FKM be used in pharmaceutical steam autoclaves?
Standard FKM has limited steam resistance and is generally not recommended for repeated SIP cycles. For aggressive chemical CIP combined with steam, specify a steam-resistant FFKM grade.
Why is peroxide-cured EPDM preferred over sulfur-cured for pharma?
Peroxide curing produces fewer extractable by-products and better heat resistance than sulfur curing. This makes peroxide EPDM the standard for food and pharmaceutical steam applications.
Do you provide certificates of conformance?
Yes. Every pharmaceutical order is supplied with a material test certificate, USP Class VI declaration, and batch traceability record. Third-party test reports are available on request.
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