In environments where corrosive chemicals, aggressive gases, or high pressures are the norm, standard washers simply won’t hold up. That’s why engineers across the chemical, pharmaceutical, and petrochemical sectors rely on expanded PTFE washers (ePTFE) to deliver long-term, leak-free performance. As a trusted expanded PTFE washers supplier, Stephens Gaskets provides high-quality sealing solutions tailored to the most demanding conditions.
This guide explores why expanded PTFE outperforms standard PTFE in sealing applications, how it supports flange integrity, and where to source PTFE flange seals that are engineered for resilience and reliability.
What Is Expanded PTFE?
Expanded PTFE (ePTFE) is a microporous form of standard PTFE that has been mechanically expanded to improve its sealing performance. The expanded structure offers greater compressibility and adaptability compared to virgin PTFE, making it ideal for gasket and washer applications.
Key properties include:
- High chemical resistance.
- Superior compressibility and recovery.
- Non-stick, low-friction surface.
- Wide temperature operating range (-200°C to +260°C).
- FDA and EN compliance for specific grades.
These attributes make ePTFE washers the preferred choice in systems where performance under pressure and exposure is critical.
Why Choose Expanded PTFE Washers?
1. Exceptional Chemical Resistance
Expanded PTFE is virtually inert to a wide range of aggressive chemicals, including acids, alkalis, solvents, and fuels-making it the go-to material for chemical-resistant washers.
2. Outstanding Sealing Under Compression
The microporous structure allows ePTFE to conform to flange surface irregularities, creating an ultra-tight seal even with low bolt loads or misaligned faces.
3. Gas and Vapour Tight
Unlike standard rubber or fibre washers, ePTFE prevents gas permeation and micro-leakage, critical in pharmaceutical and gas delivery systems.
4. Resistant to Creep and Cold Flow
Expanded PTFE maintains its shape over time, even in high-load or high-temperature scenarios, reducing the risk of joint failure.
Applications for Expanded PTFE Washers
As an experienced expanded PTFE washers supplier, Stephens Gaskets serves a variety of industries that require robust, reliable sealing:
- Chemical processing and storage tanks.
- Pharmaceutical and biotech equipment.
- Food-grade piping systems (FDA compliant on request).
- Semiconductor manufacturing environments.
- Oil & gas pipelines and refinery equipment.
- Aggressive gas or solvent lines.
Expanded PTFE washers are especially effective as PTFE flange seals, providing a dependable seal in bolted flange joints, even when bolt torque is limited.
Standard and Custom Washer Options Available
We supply both standard sizes and custom ePTFE sealing washers, with capabilities including:
- Thicknesses from 1.5mm to 6mm.
- TID/OD to suit DIN, ANSI, BS, and custom flange specs.
- TFlat and slotted profiles.
- TCustom sizes made from drawings or physical samples.
Our washers are manufactured to strict tolerances and quality standards, suitable for both OEM and maintenance applications.
Learn more about PTFE flange seals or visit the washer itself for technical data.
Why Choose Stephens Gaskets?
As a UK-based PTFE washer manufacturer with decades of experience, Stephens Gaskets delivers precision sealing solutions backed by expert support.
Why customers choose us:
- In-house machining and material conversion.
- Custom sizes and profiles to drawing or spec.
- ISO 9001-certified quality processes.
- Short lead times and UK-wide delivery.
- Technical assistance for material selection and flange matching.
We’re not just a supplier – we’re your partner in sealing performance.
When to Specify Expanded PTFE Washers
Use expanded PTFE when:
- You need chemical-resistant washers for harsh environments.
- Sealing gases or aggressive liquids under pressure.
- Flanges are misaligned or slightly damaged.
- You require PTFE flange seals that adapt under bolt load.
- A long-lasting, non-reactive solution is critical to system integrity.
Whether it’s a standard gasket or a complex custom part, we ensure every washer performs to spec.
Frequently Asked Questions
1. What’s the difference between virgin PTFE and expanded PTFE?
Virgin PTFE is more rigid and less compressible. Expanded PTFE offers improved sealing due to its microporous, flexible structure.
2. Are expanded PTFE washers reusable?
In low-stress environments, they can sometimes be reused. However, for critical sealing, we recommend replacing after each disassembly.
3. Can I buy expanded PTFE washers in bulk?
Yes. We offer both small-batch and high-volume manufacturing with consistent quality and fast lead times.
4. Do you offer FDA-approved grades?
Absolutely. We supply FDA-compliant ePTFE washers for food and pharmaceutical use on request.
Final Thoughts: Designed to Resist, Built to Last
Expanded PTFE washers offer a reliable, versatile solution where other sealing materials fall short. Their superior chemical resistance, compressibility, and thermal stability make them essential in high-risk or regulated sectors.
At Stephens Gaskets, we specialise in high-performance, chemical-resistant washers made from expanded PTFE, designed to seal with confidence. Whether you’re planning a new system or replacing aging parts, we have the experience and capabilities to deliver.