Natural cork composition sheet is an economical all-purpose gasket material made from 10/20 grind composition cork. It is supplied in rolls and sheets, and is chosen because it does the two things a gasket has to do — it compresses into a surface and it recovers as bolt load relaxes — at a lower cost per part than most rubber-binder sheet materials.
This is the general-purpose grade in the Kaxite cork sheet range. When the working environment involves oil, fuel, weather or chemical exposure, the nitrile or neoprene-binder cork rubber sheet is the better fit. For dry, light to medium duty sealing, natural cork composition sheet remains the most cost-efficient choice.
Natural cork composition sheet is produced in five standard thicknesses and five standard sheet sizes. All thicknesses below are available in every listed sheet size, so specification comes down to the flange or joint dimensions and the bolt load the gasket needs to carry.
| Thickness | 12" × 12" | 12" × 24" | 12" × 36" | 24" × 24" | 36" × 36" |
|---|---|---|---|---|---|
| 1/16" | ✓ | ✓ | ✓ | ✓ | ✓ |
| 3/32" | ✓ | ✓ | ✓ | ✓ | ✓ |
| 1/8" | ✓ | ✓ | ✓ | ✓ | ✓ |
| 1/4" | ✓ | ✓ | ✓ | ✓ | ✓ |
| 3/8" | ✓ | ✓ | ✓ | ✓ | ✓ |
| 1/2" | ✓ | ✓ | ✓ | ✓ | ✓ |
Custom thicknesses and sheet sizes can be produced on request. Send your flange drawing or required dimension and we will confirm availability.
The figures below reflect typical values for 10/20 grind natural cork composition sheet. Actual values vary slightly by thickness and by production batch — please request a batch certificate if your application has a hard specification limit.
| Property | Typical Value | Notes |
|---|---|---|
| Composition | 10/20 grind composition cork | Cork granules bound without a rubber binder |
| Thickness Range | 1/16" to 1/2" | Custom thicknesses on request |
| Sheet Sizes | 12" × 12" to 36" × 36" | Five standard sizes |
| Supply Format | Sheets and rolls | Roll format depends on thickness |
| Compressibility | Good | Compresses into surface irregularities under bolt load |
| Recovery | Good | Recovers as bolt load relaxes, maintaining seal |
| Binder | None (composition cork) | Not oil, fuel or solvent resistant |
| Primary Service | Dry, light to medium duty sealing | General industrial gasketing |
| Density | Standard composition cork density | Batch-specific; certificate available |
| Surface | Smooth, void-free | No through holes or voids in the sheet matrix |
Natural cork composition sheet has no rubber binder, so it is not the right choice for oil, fuel, solvent or chemical contact. If the seal will see petroleum-based media, specify cork and nitrile rubber sheet. If the joint is outdoors or exposed to weather and chemicals, specify cork and neoprene rubber sheet.
Composition cork sheet should be stored flat, dry and away from direct sunlight. Under those conditions it holds its dimensions and mechanical properties for extended periods, so stock can be cut to order rather than held as finished gaskets.
Cut gaskets for low-pressure water, air and dry service flanges where the joint does not see oil or chemical contact.
Gaskets and pads in compressor assemblies where moderate compressibility and good recovery are needed.
Equipment covers, inspection plates and general purpose sealing where a low-cost compressible sheet works.
Cushioning and mounting pads where the cork structure absorbs vibration and impact.
Sealing and gasket applications in air handling systems that stay dry and do not see chemical exposure.
Sheet can be die cut, punched or knife cut into customer-specific gasket shapes and pads.
Non-conductive cushioning and gasket parts in panel and enclosure assemblies.
Underlay and cushioning layers where impact absorption and long service life are required.
On-site gasket cutting from stock sheet, eliminating the wait for a custom gasket to be produced.
It is made from 10/20 grind composition cork — natural cork granules that are bonded into a sheet form without adding a rubber binder. That distinguishes it from cork rubber sheet, which adds a nitrile, neoprene or general-purpose rubber binder.
Natural cork composition sheet has no rubber binder, so it is limited to dry, light to medium duty sealing. Cork rubber sheet adds a rubber binder which improves flexibility, shelf life and resistance to oils, fuels, weather or chemicals, depending on which binder is used.
No. Without a rubber binder, natural cork composition sheet is not oil, fuel or solvent resistant. For those media, specify the cork and nitrile rubber sheet grade instead.
Five standard thicknesses: 1/16", 3/32", 1/8", 1/4", 3/8" and 1/2" — and five standard sheet sizes: 12" × 12", 12" × 24", 12" × 36", 24" × 24" and 36" × 36". Custom thicknesses and sizes can be produced on request.
Both. Natural cork composition sheet is supplied in sheet form and roll form. The availability of roll format depends on the thickness required.
No. The sheet has a smooth surface and does not contain through holes or voids within the cork matrix, which is important for thin gaskets where a void would become a leak path.
Store flat, dry and out of direct sunlight. Under those conditions the material holds its dimensions and mechanical properties for extended periods and can be cut to size on demand.
Yes. Kaxite also supplies cork and nitrile rubber sheet (H-series, MIL C 6183 B Class 1) and cork and neoprene rubber sheet (E-series, MIL C 6183 B Class 2, soft / medium / firm density), plus general cork rubber sheet for indoor light to medium duty applications.
Send us the working media, required thickness and sheet size. Kaxite will confirm availability and lead time. If your application involves oil, fuel or chemical contact, tell us and we will recommend the appropriate cork rubber grade instead.