Quick answer: Compression sheets, also known as compressed non-asbestos sheets or gasket sheets, are engineered sealing materials supplied in flat sheets or rolls. They are cut to shape on site and then compressed under flange bolt load, so the material flows into surface imperfections and forms a tight, leak-proof barrier between two mating surfaces. They are the base material for gaskets used in pipelines, pumps, heat exchangers and chemical processing vessels, and they withstand high temperatures, high pressures and aggressive media.
At Kaxite Sealing we manufacture premium-grade compression sheets that serve as the foundational material for reliable, long-lasting gaskets. Their versatility and performance make them indispensable in industries ranging from oil & gas and chemical processing to power generation and marine applications.
Selecting the correct compression sheet is paramount for safety and system integrity. Performance is dictated by the combination of material composition and physical properties. The parameters below define the full Kaxite Sealing product range.
Key specifications at a glance: density 1.6 – 2.0 g/cm³ · compressibility 5 – 12% @ 35 MPa · recovery ≥ 40% · tensile strength ≥ 7 MPa · continuous service temperature −50 °C to +400 °C · pH resistance 0 – 14 (short periods) · thickness 0.5 – 3.0 mm · standard sheet size 1500 × 1500 mm or 1250 × 1250 mm.
Our sheets are classified by their binder system and reinforcement fibres, which determine their core characteristics.
The table below outlines the standard test properties for our most common grades. Specifications are per ASTM F104, DIN 3754 and other international standards.
| Property | Test Method | Standard Grade (NBR Based) | High-Temp Grade (Aramid Fiber) | Acid-Resistant Grade | Units |
|---|---|---|---|---|---|
| Density | ASTM D792 | 1.6 – 1.8 | 1.7 – 1.9 | 1.8 – 2.0 | g/cm³ |
| Compressibility | ASTM F36 | 7 – 12% | 5 – 9% | 6 – 10% | % @ 35 MPa |
| Recovery | ASTM F36 | ≥ 45% | ≥ 40% | ≥ 50% | % |
| Tensile Strength | ASTM D828 | ≥ 8.0 | ≥ 10.0 | ≥ 7.0 | MPa |
| Temperature Range | Continuous Service | −30 °C to +120 °C | −50 °C to +400 °C | −20 °C to +200 °C | °C |
| pH Resistance Range | Immersion Test | 4 – 10 | 2 – 12 | 0 – 14 (short periods) | pH |
| Thickness Availability | Standard Sheets | 0.5 mm to 3.0 mm | 0.8 mm to 3.0 mm | 1.0 mm to 3.0 mm | mm |
| Standard Sheet Size | — | 1500 mm × 1500 mm or 1250 mm × 1250 mm (custom sizes available) | mm | ||
Grade selection is based on the PITT criteria: Pressure, Interior media (chemical compatibility), Temperature, and Type of flange (surface finish and available bolt load).
Always consult our technical datasheets for chemical resistance charts and temperature limits. When in doubt, our technical support team can recommend a grade based on your specific operating conditions.
A compression sheet is the raw, semi-finished material supplied in large sheets or rolls, which a fabricator or maintenance technician cuts to the required shape and size on site. A pre-cut gasket is already die-cut or water-jet cut to a specific flange dimension. Compression sheets offer superior flexibility for custom or odd-shaped flanges, reduce inventory costs because one sheet can produce many gaskets, and allow optimal material utilisation with minimal waste. Kaxite Sealing supplies the high-quality sheet material, enabling you to fabricate gaskets as needed.
Selection is based on the "PITT" criteria: Pressure, Interior Media (chemical compatibility), Temperature, and Type of flange (surface finish, bolt load). Always consult our technical datasheets for chemical resistance charts and temperature limits. For example, use our NBR-based grade for oil pipelines, the high-temperature aramid grade for exhaust systems, and the specialised acid-resistant grade for sulphuric acid service. When in doubt, our technical support team can provide a recommendation based on your specific operating conditions.
First, ensure the flange surfaces are clean, dry and free of old gasket material. Trace the flange outline onto the sheet, including bolt holes. Use sharp utility knives, shears or hole punches for clean cuts; for production, die-cutting or CNC cutting is recommended. The cut gasket should fit snugly without overhang. During installation, align the gasket carefully, hand-tighten all bolts in a crisscross pattern, then torque to the specified value in multiple stages using the same pattern. This ensures even compression and flow of the sheet material, creating a uniform seal.
Yes. We offer specific grades that are certified and compliant with international standards for potable water contact, such as NSF/ANSI 61, WRAS or KTW. These sheets are formulated without harmful plasticisers or extractable metals to ensure water safety. It is crucial to specify this requirement when ordering to receive the correct, certified material for your water treatment or distribution project.
These are two of the most critical properties. Compressibility indicates how much the sheet will thin under flange bolt load. A proper range (such as our 7 – 12%) allows the material to flow into flange micro-grooves, ensuring surface intimacy. Recovery is the material's ability to return to its original thickness after compression is released. High recovery (such as our ≥ 45%) is vital for maintaining the seal during system pressure cycles, thermal fluctuations or slight flange movements. A sheet with poor recovery may take a permanent set and eventually leak.
Absolutely. All Kaxite Sealing compression sheets are 100% non-asbestos. We use modern, safer synthetic fibres such as aramid, glass and cellulose, combined with high-quality elastomers and fillers, to provide performance that meets or exceeds that of old asbestos-based materials without the associated health risks. Our manufacturing process and material sourcing adhere to strict international health and safety regulations.
To preserve their properties, store Kaxite Sealing sheets in a cool, dry place away from direct sunlight, ozone sources (such as electric motors) and extreme temperatures. The ideal storage temperature is between 10 °C and 25 °C. Keep the sheets flat or rolled without sharp bends, and avoid stacking heavy objects on them. Under these conditions, our sheets have a recommended shelf life of 5 years from the date of manufacture. Always inspect the material for dryness, cracking or stiffness before use if it has been stored for an extended period.
The robustness and adaptability of our compression sheet products make them suitable for a vast array of sealing challenges.
Kaxite Sealing provides the material integrity that these critical industries depend on. Need help matching a grade to your operating conditions? Contact our technical team for a datasheet and recommendation.
