In the world of industrial sealing and fluid handling, few materials have revolutionized performance and reliability like Polytetrafluoroethylene, commonly known as PTFE or Teflon®. At Kaxite Sealing, we specialize in engineering high-performance PTFE Washers that set the benchmark for chemical resistance, thermal stability, and low friction. These flat, disc-shaped sealing elements are critical components in countless industries, from aggressive chemical processing and semiconductor manufacturing to food & beverage and pharmaceutical production. Unlike conventional rubber or fiber washers, PTFE washers offer near-universal compatibility, ensuring a leak-free seal in the most challenging environments where other materials would quickly degrade and fail.
Our commitment at Kaxite Sealing is to provide not just a component, but a reliability upgrade. Every washer is precision-machined or molded from high-grade, virgin PTFE polymers, ensuring consistent density, purity, and performance. Whether you are battling extreme temperatures, corrosive media, or require FDA-compliant materials for food contact, our PTFE washers deliver uncompromising sealing integrity.
Kaxite Sealing PTFE washers are available in a comprehensive range of sizes, thicknesses, and formulations to meet specific application needs. Below are our standard specifications. Custom configurations are available upon request.
| Grade | Description | Color | Key Applications |
|---|---|---|---|
| Virgin PTFE | 100% pure, unfilled PTFE. Offers the highest chemical purity and best electrical properties. | White | Ultra-pure chemical, semiconductor, food contact, electrical insulation. |
| Glass Filled PTFE | PTFE compounded with glass fibers. Improves compression resistance and reduces creep (cold flow). | Brown/Tan | Flange gaskets, heavy load bearings, applications requiring improved dimensional stability. |
| Carbon Filled PTFE | PTFE filled with carbon particles. Enhances thermal conductivity and wear resistance. | Black | Wear pads, bushings, applications involving sliding friction and heat dissipation. |
| Stainless Steel Filled PTFE | PTFE filled with stainless steel powder. Greatly improves load-bearing capacity and thermal conductivity. | Gray Metallic | Heavy-duty thrust washers, compressor components, high-load environments. |
| FDA Compliant PTFE | Specially formulated virgin PTFE meeting FDA CFR 21 and EU regulations for food contact. | White | Food processing, beverage, dairy, and pharmaceutical equipment. |
| Inside Diameter (ID) | Outside Diameter (OD) | Thickness | Standard |
|---|---|---|---|
| 2 mm to 50 mm | 5 mm to 200 mm | 0.5 mm, 1.0 mm, 1.5 mm, 2.0 mm, 3.0 mm | Metric (DIN) |
| #4 to 1" | 1/4" to 8" | 1/32", 1/16", 1/8", 1/4" | Imperial (ANSI/ASME) |
| Property | Test Method | Value / Rating |
|---|---|---|
| Density | ASTM D792 | 2.14 - 2.20 g/cm³ |
| Tensile Strength | ASTM D638 | 25 - 35 MPa |
| Elongation at Break | ASTM D638 | 300 - 500% |
| Compression Set (22 hrs @ 25°C) | ASTM D395 | 40 - 60% |
| Coefficient of Friction (Dynamic) | ASTM D1894 | 0.05 - 0.10 |
| Continuous Service Temperature | - | -268°C to +260°C (-450°F to +500°F) |
| Dielectric Strength | ASTM D149 | > 40 kV/mm |
Kaxite Sealing PTFE washers are deployed across a diverse spectrum of industries where failure is not an option:
What is the main difference between a PTFE washer and a rubber washer?
The primary differences are chemical resistance and temperature capability. Rubber washers (like NBR or EPDM) are elastomeric and seal well within their specific chemical and thermal limits, but they can swell, degrade, or become brittle. A PTFE washer is a thermoplastic with near-universal chemical inertness and can handle a much broader temperature range (-268°C to +260°C) without losing its properties. PTFE is also non-porous and has a lower coefficient of friction.
Can PTFE washers be used for high-pressure applications?
Virgin PTFE has a tendency to cold flow (creep) under sustained high pressure and load, which can lead to seal relaxation. For high-pressure flange connections, we recommend using our filled PTFE grades (e.g., glass-filled or stainless steel-filled). These compounds significantly reduce cold flow and improve load-bearing capacity, making them suitable for many high-pressure static sealing applications. For dynamic seals or extremely high pressures, a different seal design may be required.
How do I choose the right PTFE grade for my application?
Selection depends on the operating environment. Choose Virgin PTFE for maximum chemical purity, electrical insulation, or food contact. Opt for Glass-Filled PTFE when you need improved mechanical strength, reduced creep, and better dimensional stability under load. Carbon-Filled PTFE is ideal for applications requiring enhanced wear resistance and thermal conductivity. For the highest load-bearing capacity and thermal conductivity, select Stainless Steel-Filled PTFE. Our Kaxite Sealing engineering team can assist with specific recommendations.
Are PTFE washers reusable?
PTFE washers can often be reused if they have not been permanently deformed, over-compressed, or chemically contaminated. Their non-stick surface makes them easy to clean. However, for critical sealing applications, especially in industries like pharmaceuticals or semiconductors, it is generally recommended to use new washers during maintenance to guarantee perfect sealing integrity and avoid any risk of contamination or leakage.
How should PTFE washers be installed and torqued?
PTFE is a softer material than metal. Proper installation is key. Ensure flange faces are clean, smooth, and free of scratches. Place the washer evenly. Use a crisscross torque pattern when tightening bolts to apply pressure uniformly. Avoid over-torquing, as this can cause excessive cold flow and extrusion of the PTFE, leading to seal failure. Refer to our Kaxite Sealing technical datasheets for recommended bolt load and torque values based on washer dimensions and pressure.
Does Kaxite Sealing offer custom-sized or shaped PTFE washers?
Absolutely. While we stock a wide range of standard sizes, our core expertise at Kaxite Sealing lies in providing custom-engineered sealing solutions. We can manufacture PTFE washers to non-standard inside/outside diameters, special thicknesses, and with unique features such as lips, grooves, or co-molded inserts. We also offer prototypes and low-volume production runs.
Are Kaxite Sealing PTFE washers resistant to steam and high-temperature water?
Yes, PTFE is an excellent material for steam and high-temperature water applications within its continuous temperature rating. It will not hydrolyze or degrade in hot water or steam. However, for superheated steam or systems with rapid thermal cycling, it's important to consider the pressure and the potential for creep. A filled PTFE grade may provide longer service life in such demanding steam services.
What certifications do Kaxite Sealing PTFE products hold?
Our manufacturing processes are ISO 9001:2015 certified. Our virgin PTFE material is sourced from reputable suppliers and comes with full traceability. We offer specific grades that are compliant with FDA CFR 21, EU Regulation 10/2011 for food contact, and USP Class VI for pharmaceutical applications. Certificates of Compliance (CoC) and Material Test Reports (MTR) are available upon request.
