Flexible graphite gaskets are high-performance sealing components made from pure exfoliated graphite, designed to provide excellent resistance to extreme temperatures, corrosive chemicals, and high pressure. These gaskets are known for their flexibility, which allows them to conform to uneven flange surfaces, ensuring a tight and reliable seal in demanding industrial applications. They are widely used in industries such as chemical processing, power generation, oil and gas, and manufacturing, where durability and efficiency are critical.
Understanding the technical specifications of flexible graphite gaskets is essential for selecting the right product for your needs. Below are the key parameters detailed in lists and a table for clarity.
| Parameter | Standard Value | Customizable Options | Testing Standards |
|---|---|---|---|
| Thickness | 0.5 mm to 3.0 mm | Available in custom thicknesses up to 6.0 mm | ASTM F104 |
| Width/Size | Standard sheets: 1m x 1m; Rolls: various widths | Cut-to-size shapes, rings, or full-face gaskets | ISO 9001 |
| Density | 70 lbs/ft³ (1.12 g/cm³) | 60-110 lbs/ft³ (0.96-1.76 g/cm³) | ASTM D3802 |
| Compression Strength | 5,000 psi (34.5 MPa) | Adjustable based on density and application | ASTM F36 |
| Maximum Pressure | 2,000 psi (13.8 MPa) | Higher pressures with reinforced versions | ASME B16.20 |
| Temperature Limit (Oxidizing) | 850°F (454°C) | Coated options for enhanced oxidation resistance | ASTM E831 |
| Thermal Conductivity | 150 W/m·K | Varies with density and orientation | ASTM E1225 |
Flexible graphite gaskets are versatile and used in numerous industries due to their exceptional properties. Common applications include:
These gaskets can be supplied in various forms, such as sheets, tapes, or pre-cut shapes, to meet specific installation requirements.
Compared to traditional materials like rubber, PTFE, or compressed non-asbestos fibers, flexible graphite gaskets offer several benefits:
Here are some frequently asked questions to help users understand these gaskets better.
What are the main benefits of using flexible graphite gaskets?
Flexible graphite gaskets provide exceptional thermal stability, chemical resistance, and sealing performance under extreme conditions. They are highly compressible, ensuring a tight seal on uneven surfaces, and offer long-term reliability with minimal maintenance, making them cost-effective for industrial applications.
Can flexible graphite gaskets be used in oxidizing atmospheres?
Yes, but with limitations. In oxidizing environments, the maximum continuous service temperature is typically 850°F (454°C). For higher temperatures or prolonged exposure, specially coated or treated graphite gaskets are recommended to prevent oxidation and extend lifespan.
How do I choose the right density for my application?
Density selection depends on factors like pressure, temperature, and flange conditions. Lower densities (e.g., 60-70 lbs/ft³) offer higher compressibility for irregular surfaces, while higher densities (e.g., 90-110 lbs/ft³) provide better strength and resistance to blow-out in high-pressure systems. Consult technical datasheets or a supplier for guidance.
Are flexible graphite gaskets suitable for food or pharmaceutical industries?
Yes, but ensure they meet relevant standards like FDA requirements for food contact. Pure flexible graphite is generally inert and safe, but always verify compliance with industry-specific regulations to avoid contamination.
What maintenance is required for these gaskets?
Flexible graphite gaskets require minimal maintenance due to their resistance to creep and relaxation. Regular inspections for signs of oxidation, wear, or damage in cyclic applications are advised. Re-torquing bolts after initial installation may be necessary to maintain seal integrity, but they often perform reliably without frequent adjustments.
Can these gaskets be used with all types of flanges?
They are compatible with most flange types, including raised face, flat face, and ring-type joints. However, for very high pressures or dynamic loads, reinforced versions with metal inserts might be needed. Always ensure the gasket size and rating match the flange specifications to prevent failures.
How do I handle and store flexible graphite gaskets?
Store in a dry, cool place away from direct sunlight and oxidizing agents. Handle with care to avoid tearing or contamination. Use clean gloves during installation to prevent oil or dirt transfer, which could affect performance.
What are the environmental impacts of flexible graphite gaskets?
They are environmentally friendly, as graphite is a natural mineral and recyclable. Unlike asbestos-based gaskets, they pose no health risks during handling or disposal. Always follow local regulations for disposal or recycling.
