Product Overview
Reliable custom rubber parts for industrial applications
Quick Answer
PTFE O-rings are fluoropolymer sealing rings for chemical equipment, valves, connectors, instruments and fluid handling systems. They are mainly used for static sealing where chemical resistance, low friction and dimensional stability are important. Inner diameter, cross-section, PTFE grade, tolerance, surface finish, inspection requirements and packaging can be customized.
PTFE O-Rings — High-Performance Seals for Extreme Chemical & Temperature Environments
PTFE O-rings are fluoropolymer sealing rings used in applications requiring chemical resistance, low friction and dimensional stability under demanding operating conditions. Unlike elastomer O-rings, PTFE O-rings have limited elasticity and are mainly selected for static or low-compression sealing designs. Inner diameter, cross-section, tolerance, compound grade and packaging can be customized according to drawings or samples.
Product Overview
What Are PTFE O-Rings?
PTFE (Polytetrafluoroethylene) is a synthetic fluoropolymer thermoplastic, not a traditional elastomer, which gives it a uniquely different performance profile compared to rubber O-rings such as NBR, EPDM, or Viton. PTFE O-rings are typically white in color with a Shore D hardness of 55–90, a tensile strength of 3,625–4,496 psi, and a minimum elongation of 300–400%. Because pure PTFE has low elastic recovery, it is ideally suited for static sealing applications, or used as backup rings in high-pressure dynamic assemblies.
Key Technical Specifications
| Property | Value |
|---|---|
| Material | Virgin PTFE / Filled PTFE (glass, carbon, bronze) |
| Color | White (standard) |
| Hardness | 55–90 Shore D |
| Tensile Strength | 3,625–4,496 psi (25–31 MPa) |
| Elongation at Break | 300–400% min |
| Operating Temperature | -200°C to +260°C (-328°F to +500°F) |
| Pressure Rating | Up to 1,500 psi (static); higher with backup rings |
| Chemical Resistance | Virtually universal — resistant to nearly all acids, bases, solvents |
| Coefficient of Friction | 0.04–0.10 (one of the lowest of any solid) |
| FDA/USDA Compliance | Yes — food and pharmaceutical grade marcorubber+1 |
| Standards | AS568, ISO 3601, DIN 3771, JIS B 2401 trelleborg+1 |
PTFE O-Ring Performance Advantages
PTFE O-rings outperform rubber alternatives in several critical dimensions:
- Universal chemical resistance — inert to virtually all industrial acids, alkalis, solvents, fuels, and oxidizers, including concentrated sulfuric acid, hydrofluoric acid, and chlorine
- Extreme temperature range — stable from cryogenic –200°C up to continuous +260°C service
- Ultra-low friction — coefficient of friction as low as 0.04, reducing wear and extending component life in semi-dynamic applications
- Non-stick surface — prevents media buildup, simplifying CIP (Clean-in-Place) and SIP (Sterilize-in-Place) processes in food and pharma lines
- Low outgassing — suitable for vacuum and semiconductor environments
- FDA/USP compliance — meets food contact and pharmaceutical purity requirements
- Excellent shelf life — PTFE does not age, harden, or degrade in storage
- Electrically insulating — appropriate for electrical and electronic sealing applications
PTFE vs. Elastomeric O-Rings — Fundamental Differences
PTFE O-rings are fundamentally different from rubber/elastomeric O-rings in both material behavior and application design. Understanding these differences is critical to correct specification:
| Property | PTFE O-Ring | Elastomeric O-Ring (e.g. FKM) |
|---|---|---|
| Material type | Semi-rigid fluoropolymer plastic | Elastomeric rubber |
| Hardness | Shore D 55–90 | Shore A 40–90 |
| Elastic recovery | Low — does not spring back like rubber | High — self-energizing |
| Compression set | High at elevated temp | Low (good grades) |
| Chemical resistance | Near-universal | Compound-dependent |
| Temperature range | -200°C to +260°C | Compound-dependent (max +320°C for FFKM) |
| Friction coefficient | 0.04–0.10 (lowest of any solid) | 0.5–1.5 |
| FDA compliance | Virgin PTFE — inherently compliant | Grade-dependent |
| Pressure capability | Low-medium (static only recommended) | High (with back-up rings) |
| Primary seal type | Static face seal preferred | Static and dynamic |
Critical design note: Because PTFE has low elastic recovery compared to rubber, PTFE solid O-rings require higher groove compression (25–35%) and more precise groove design to achieve reliable sealing. They are best suited to static face seal applications and axial flange-type connections. For dynamic applications requiring both chemical resistance and elastic sealing, PTFE-encapsulated O-rings (rubber core + PTFE jacket) are the preferred solution.
Industry Applications
PTFE O-rings are the preferred sealing solution across the most demanding global industries:
- Chemical Processing — pumps, valves, and reactors handling corrosive acids, bases, and solvents
- Pharmaceutical Manufacturing — sterile process equipment, filling machines, and bioreactors requiring USP/FDA compliance
- Food & Beverage — CIP/SIP-compatible seals in mixers, conveyors, and bottling lines
- Oil & Gas — downhole tools, wellhead equipment, and refinery valves exposed to hydrocarbons
- Aerospace & Aviation — hydraulic systems and fuel line seals under extreme thermal cycling
- Semiconductor & Electronics — ultra-clean, low-outgassing seals for wafer processing chambers
- Automotive — paint spray guns, steering systems, and fuel systems
- Cryogenics — LNG equipment and liquid nitrogen/oxygen systems down to -200°C
Available Grades & Compound Options
Pure (virgin) PTFE offers the highest chemical resistance, while filled PTFE compoundsenhance mechanical properties for specific applications:
Virgin PTFE — maximum chemical resistance, FDA/USP grade; ideal for pharmaceutical and food applications
- Glass-filled PTFE (15–25%) — improved compressive strength and creep resistance for high-load static seals
- Carbon/graphite-filled PTFE — enhanced wear resistance and thermal conductivity for semi-dynamic and backup ring use
- Bronze-filled PTFE — superior load-bearing capacity and thermal dissipation for high-pressure hydraulic systems
- MoS₂-filled PTFE — low friction, excellent dry-running performance for dynamic applications
Standard Sizes & Custom Options
Julong Rubber stocks and manufactures PTFE O-rings to all major international standards:
- AS568 (USA standard) — Dash numbers -001 through -475
- ISO 3601 / DIN 3771 (Metric standard) — Full size range available
- JIS B 2401 (Japanese standard)
- Custom dimensions — Any ID × CS combination available with MOQ as low as 100 pcs
Cross-section (cord) diameters available: 1.0 mm to 12.0 mm
Inside diameters: 0.5 mm to 2,000 mm+
Tolerances: Per AS568B / ISO 3601 Class A or customer drawing
Why Choose Julong Rubber as Your PTFE O-Ring Supplier?
- ✅ 30+ years of fluoropolymer seal manufacturing experience
- ✅ ISO 9001:2015 certified quality management system
- ✅ In-house material testing — hardness, tensile, compression set, and chemical immersion
- ✅ Custom formulations & drawings accepted — OEM and private label available
- ✅ Fast lead times — standard sizes shipped within 3–5 business days; custom orders 7–15 days
- ✅ Global shipping — DDP/DAP Europe, North America, and Middle East
- ✅ Low MOQs — ideal for MRO distributors, OEM integrators, and project procurement
Ordering & Customization
To request a quote or samples, provide the following:
- Inside Diameter (ID) and Cross-Section (CS) — or the standard size number (e.g., AS568-214)
- PTFE grade required — virgin, glass-filled, carbon-filled, etc.
- Application details — media, pressure, temperature, and static/dynamic
- Required quantity and packaging
- Applicable standard or drawing reference
FAQ
What are PTFE O-rings used for?
PTFE O-rings are used for sealing applications where chemical resistance, dimensional stability and low-friction behavior are required. They are commonly used in valves, pumps, chemical equipment, connectors, instruments and fluid handling systems, especially where rubber compounds may swell or degrade.
Are PTFE O-rings elastic like rubber O-rings?
No. PTFE O-rings have much lower elasticity than rubber O-rings. They do not recover in the same way after compression. For this reason, groove design, compression rate, installation method and sealing surface condition must be reviewed carefully before selection.
Can PTFE O-rings replace rubber O-rings directly?
Not always. PTFE O-rings can solve chemical compatibility or low-friction requirements, but they cannot simply replace rubber O-rings in every groove. The existing groove may need design review because PTFE has different hardness, compression behavior and elastic recovery.
What is the difference between virgin PTFE and filled PTFE?
Virgin PTFE is often selected for broad chemical resistance and clean sealing applications. Filled PTFE can be reviewed when improved wear resistance, creep resistance or dimensional stability is required. The suitable grade depends on media, temperature, pressure, movement and mating surface conditions.
Can custom PTFE O-ring sizes be manufactured?
Yes. Inner diameter, cross-section, outer diameter, tolerance and surface finish can be customized according to drawings, standard references or physical samples. Buyers should provide groove dimensions and operating conditions so the PTFE O-ring can be reviewed accurately.
Are material documents available?
Material documentation is available upon request for applicable PTFE grades. RoHS, REACH, FDA and other documentation options can be reviewed according to the selected material and application requirements. Buyers should specify documentation needs before quotation and sample production.
Request a Custom Quote
Send your PTFE O-ring drawing, standard reference, size list or physical sample for technical review. Please include ID, cross-section, PTFE grade, tolerance, groove dimensions, contact media, temperature, pressure, sealing condition, required quantity, annual demand and documentation requirements.
