A Cork Sheet is a versatile, sustainable engineered material crafted from the bark of the cork oak tree (*Quercus suber*). At Kaxite Sealing, we specialize in producing high-performance cork sheets that leverage the natural properties of cork—lightweight, compressible, resilient, and impermeable to liquids and gases. This makes our sheets an exceptional choice for a vast array of industrial, commercial, and DIY applications, from sealing and gasketing to insulation and acoustic damping. As a carbon-negative and renewable resource, choosing cork aligns with eco-conscious manufacturing and building practices without compromising on technical performance.
Our cork sheets offer a unique combination of benefits that synthetic materials often struggle to match. Here’s why engineers, builders, and fabricators prefer Kaxite Sealing cork products:
Kaxite Sealing provides cork sheets in various compositions and densities to meet precise engineering requirements. Our standard product lines include natural cork, composition cork (cork granules bound with resins), and rubber-cork blends.
| Grade Type | Description | Primary Binder/Blend | Best For |
|---|---|---|---|
| Natural Cork | Pure cork bark, lightly processed. Highest elasticity and natural properties. | None (Self-agglomerated) | Wine bottle stoppers, bulletin boards, craft applications. |
| Composition Cork | Granulated cork bonded with synthetic or natural resins. Uniform density and enhanced resistance. | Phenolic, Urea, or Polyurethane Resins | Gaskets, seals, vibration dampers, expansion joints. |
| Rubber-Cork Blend | Cork granules compounded with nitrile, SBR, or other elastomers. Improved flexibility and oil resistance. | NBR, SBR Rubber | Automotive gaskets, industrial seals in oily environments. |
| Parameter | Test Standard | Typical Range (Kaxite Sealing) | Notes |
|---|---|---|---|
| Density | ASTM D1622 | 140 - 550 kg/m³ | Varies by grade. Lower density for insulation, higher for gasketing. |
| Compression Set (24h @ 23°C) | ASTM D395 | 15% - 40% | Indicates recovery ability. Lower percentage means better recovery. |
| Tensile Strength | ASTM D1623 | 0.5 - 2.0 MPa | Measures resistance to pulling forces. |
| Thermal Conductivity (K-value) | ASTM C518 | 0.036 - 0.042 W/m·K | Excellent insulating property. |
| Water Absorption (24h immersion) | ASTM D570 | < 5% by volume | High resistance to water uptake. |
| Temperature Range | - | -40°C to 120°C (Short peak to 150°C) | Safe continuous operating range. Specific grades may vary. |
| Flammability | UL 94 | HB Rating | Self-extinguishing; slow burning. |
| Standard Sheet Dimensions | - | 1000mm x 500mm, 1220mm x 610mm, 1250mm x 625mm | Custom sizes and rolls available on request. |
| Standard Thickness | - | 0.5mm, 1mm, 1.5mm, 2mm, 3mm, 5mm, 6mm, 10mm, 12mm, up to 50mm | Thickness tolerance typically ±0.2mm to ±0.5mm. |
The functional properties of cork sheet material make it indispensable across multiple sectors. Kaxite Sealing products are trusted in the following applications:
What exactly is cork sheet made from?
Cork sheet is primarily manufactured from the granulated bark of the cork oak tree. For composition grades, these granules are cleaned, sorted, and then bonded together under heat and pressure using food-safe or industrial resins (like phenolic or polyurethane) to form sheets of consistent density and thickness. Natural cork sheets are formed by expanding the cork's own resins under steam.
Why choose cork over synthetic rubber or foam for sealing?
Cork offers a unique balance of compressibility, recovery, and natural resistance that synthetics often replicate only through complex compounding. It is inherently resilient, provides a reliable seal on uneven surfaces, and is environmentally sustainable. For static sealing applications where temperatures do not exceed 120°C, cork often outperforms many synthetics in cost-effectiveness and longevity.
Is cork sheet resistant to oils and fuels?
Pure composition cork has fair resistance to some oils and fuels but may swell or degrade with prolonged exposure. For applications involving hydrocarbon fluids, Kaxite Sealing specifically recommends our Rubber-Cork Blend grades (e.g., with Nitrile rubber). These blends combine cork's compressibility with the superior oil and fuel resistance of the elastomer, making them ideal for automotive and industrial fluid systems.
What is the maximum temperature a cork sheet can withstand?
Standard composition cork sheets from Kaxite Sealing have a safe continuous operating temperature range of -40°C to 120°C. They can withstand short-term peaks up to 150°C. For higher temperature applications, special high-temperature resistant binders can be used, but it's crucial to consult our technical team as prolonged heat can cause the resins to harden and reduce compressibility over time.
How do I select the correct density for my application?
Density is a critical selection factor. Lower density cork (140-250 kg/m³) is best for thermal and acoustic insulation, where weight and air entrapment are key. Medium density (250-400 kg/m³) is versatile for general-purpose gasketing and vibration damping. High density (400-550+ kg/m³) is recommended for heavy-duty gaskets, expansion joints, and applications requiring high compression resistance and minimal creep. Our sales engineers can help you specify based on your flange pressure and media.
What is "compression set" and why is it important?
Compression set is a measure of a material's ability to return to its original thickness after being compressed for a prolonged period. A low compression set percentage (e.g., 15-25%) indicates excellent recovery, meaning the gasket or seal will maintain its clamping force and sealing ability over time. A high compression set means the material permanently flattens, which can lead to seal failure. Kaxite Sealing optimizes our cork formulations for optimal recovery.
How do I cut and fabricate cork sheets?
Cork sheets are user-friendly and can be fabricated with standard workshop tools. For manual cutting, a sharp utility knife, scalpel, or scissors (for thinner sheets) works well. For production, die-cutting, CNC knife cutting, or laser cutting (with proper ventilation) are highly effective. Punching holes is straightforward with arch or hollow punches. Always cut in a well-ventilated area as fine cork dust can be generated.
Do I need to use a sealant or adhesive with a cork gasket?
While many cork gaskets create an effective seal through compression alone, applying a thin, even layer of a compatible gasket sealant or adhesive can enhance the seal, especially on rough surfaces or for applications involving low flange pressures. It also helps hold the gasket in place during assembly. Use non-hardening, flexible sealants. Kaxite Sealing can advise on compatible products.
How should cork sheets be stored?
Store cork sheets in a cool, dry, and flat environment away from direct sunlight, extreme heat, and moisture. Ideally, keep them in their original packaging until use. Stack sheets flat to prevent curling or warping. Proper storage ensures the material retains its properties and dimensional stability.
Is Kaxite Sealing cork sheet environmentally friendly?
Absolutely. Cork is one of the most sustainable materials on the planet. The harvesting process does not harm the tree, which regenerates its bark. Our primary source plantations in Portugal and the Mediterranean are managed under strict sustainable forestry practices. Furthermore, our composition cork sheets often use recycled cork granules and eco-friendly binders, minimizing waste. Choosing Kaxite Sealing cork supports a circular economy and reduces carbon footprint.
Can you supply custom-sized sheets or specific shapes?
Yes. While we stock a wide range of standard sheet sizes and thicknesses, Kaxite Sealing excels at providing custom solutions. We can precision-die-cut parts to your exact drawings, supply rolls of specific widths, or manufacture sheets with non-standard thicknesses and densities. Contact our team with your technical drawings or specifications for a custom quote.
What quality certifications do Kaxite Sealing products hold?
Our manufacturing facilities and processes adhere to international quality standards. Our cork sheets are tested to relevant ASTM, ISO, and DIN standards. We can provide material test reports (MTRs) for critical applications. Specific grades can be formulated to meet requirements for FDA compliance, REACH, and RoHS for use in food contact or regulated industries.
With decades of expertise in engineered sealing solutions, Kaxite Sealing stands as a leader in high-performance cork sheet manufacturing. We are not just suppliers; we are technical partners. Our in-depth knowledge of cork's behavior under different operational conditions allows us to guide customers to the optimal material grade for their specific challenge—be it sealing a high-temperature oven door, insulating a cryogenic pipeline, or damping vibration in a precision machine.
Our commitment to quality is evident in our rigorous raw material selection, controlled manufacturing process, and final product inspection. We invest in sustainable forestry partnerships to ensure a long-term, ethical supply chain. Whether you need a standard sheet for a maintenance repair or a custom-designed component for a new product launch, Kaxite Sealing delivers consistent quality, reliable performance, and expert support. Trust the natural advantages of cork, enhanced by Kaxite Sealing's technical proficiency, for your next project.
