Custom expanded graphite gasket supplier

Expanded graphite gaskets, also known as flexible graphite gaskets, are high-performance sealing solutions engineered for demanding industrial applications. At Kaxite Sealing, we specialize in manufacturing premium-grade expanded graphite gaskets that deliver exceptional reliability under extreme temperature and pressure conditions. These gaskets are manufactured from pure, exfoliated graphite without binders, resulting in a material with superior conformability, thermal stability, and chemical resistance. They are the go-to choice for sealing flanges in critical systems where leak prevention is paramount.

The unique structure of our expanded graphite material allows it to flow into minor imperfections on flange faces, creating a tight, leak-free seal. Unlike traditional gasket materials, Kaxite Sealing's expanded graphite maintains its integrity across a wide temperature range and is highly resistant to creep relaxation, ensuring a lasting seal throughout maintenance cycles. This makes our products indispensable in industries such as chemical processing, power generation, oil & gas, petrochemical, and refining.

Key Features & Advantages of Kaxite Sealing Expanded Graphite Gaskets

• Exceptional Thermal Conductivity: Efficiently transfers heat, preventing localized overheating.
• Wide Temperature Range: Performs reliably from cryogenic temperatures up to 3000°F (1650°C) in non-oxidizing atmospheres.
• Superior Chemical Resistance: Inert to most chemicals, acids, and solvents, except strong oxidizing agents.
• Excellent Conformability & Sealability: Compresses easily to fill surface irregularities, ensuring a perfect seal even on imperfect flanges.
• Low Creep Relaxation: Maintains bolt load and sealing force over extended periods, reducing the need for re-torquing.
• High Compressibility & Recovery: Accommodates thermal cycling and system vibrations without losing sealing performance.
• Non-Contaminating: Pure graphite is clean and will not foul process fluids.
• Easy Installation & Removal: Does not stick to flange faces, simplifying maintenance and replacement.

Detailed Product Specifications & Parameters

Kaxite Sealing offers a comprehensive range of expanded graphite gasket products tailored to various standards, pressures, and service conditions. Below are the detailed specifications for our standard sheet and tape products, as well as common gasket styles.

1. Expanded Graphite Sheet & Tape Material Properties

2. Standard Gasket Styles & Configurations

Kaxite Sealing expanded graphite gaskets are available in multiple forms to suit specific application requirements:

• Plain Sheets: Cut into custom shapes and sizes for flat-face and raised-face flanges.
• Tapes & Rolls: Used for wrapping, packing, or on-site fabrication of simple gaskets.
• Corrugated/Embossed Sheets: Feature a patterned surface for enhanced sealing on low bolt-load applications.
• Laminated Gaskets: Graphite laminated with stainless steel, tanged metal, or perforated metal cores for added handling strength, dimensional stability, and blow-out resistance.
• Spiral Wound Gaskets with Graphite Filler: For high-pressure/temperature applications per ASME B16.20/EN 1514 standards.
• Ring Joint Gaskets (RTJ): Machined from solid graphite or laminated graphite/metal for API ring groove flanges.

3. Common Dimensions & Standards

Expanded Graphite Gaskets - Frequently Asked Questions (FAQ)

Q: What are the primary applications for expanded graphite gaskets?
A: Expanded graphite gaskets from Kaxite Sealing are ideal for sealing a wide variety of aggressive media in challenging environments. Common applications include heat exchangers, boiler manways, turbine casings, chemical reactor flanges, compressor systems, and high-temperature pipe flanges in power plants, refineries, and chemical processing facilities. They are particularly suited for services involving steam, hot oils, acids, alkalis, hydrocarbons, and many solvents.

Q: Can expanded graphite gaskets be used with all flange types and surfaces?
A: They are highly versatile and perform well on most standard flange faces, including flat face (FF), raised face (RF), and male-and-female (M&F) types. Their excellent conformability makes them forgiving of minor surface scratches or imperfections. For tongue-and-groove (T&G) flanges, a specifically designed gasket with controlled compression is recommended. It is always crucial to ensure the flange surface finish is within the specified range (typically 125 to 500 µin Ra) for optimal sealing.

Q: What is the maximum pressure and temperature rating for these gaskets?
A: The ratings depend on the specific gasket construction. Pure expanded graphite sheet gaskets are generally used for pressures up to Class 300 and temperatures from cryogenic up to 3000°F (1650°C) in inert/reducing atmospheres. In continuous air/oxidizing service, the safe limit is typically 850-900°F (454-482°C) to prevent oxidation. For higher pressures, laminated or spiral wound gaskets with graphite filler are used, which can handle pressure classes up to 2500 and similar high temperatures.

Q: How do I select the correct thickness for my application?
A: Thickness selection is based on flange type, surface condition, bolt load, and media. A common guideline: use 1.5mm for standard raised face flanges with good surface finish. For flanges with larger gaps, warpage, or poor surface conditions, a thicker gasket (e.g., 2.0mm or 3.0mm) may be needed to ensure proper conformability. For spiral wound gaskets, standard thicknesses like 3.2mm (1/8") and 4.5mm (11/64") are standard. Consulting Kaxite Sealing's engineering team with your specific parameters is always recommended.

Q: Are there any chemicals or media that are incompatible with expanded graphite?
A: Yes. While expanded graphite has outstanding chemical resistance to most acids, alkalis, and organic compounds, it is not recommended for use with strong oxidizing agents such as concentrated nitric acid, sulfuric acid above 98%, bromine, chlorine gas (wet), and certain potent oxidizers like perchloric acid. These agents can intercalate into the graphite structure and cause rapid oxidation or degradation. Always verify chemical compatibility for your specific service.

Q: What are the key installation precautions for expanded graphite gaskets?
A: Proper installation is critical. Ensure flange surfaces are clean, dry, and free of old gasket material and debris. Do not use lubricants or anti-stick compounds on the gasket surface. Align the gasket carefully centered on the flange. Use a calibrated torque wrench and follow a star-pattern, multi-pass bolt tightening procedure to achieve the recommended seating stress evenly. Avoid over-compression, which can cause material splitting, especially on pure graphite sheets.

Q: What is the difference between expanded graphite and PTFE as a gasket material?
A: While both offer excellent chemical resistance, they serve different temperature domains. PTFE (Teflon) is limited to about 500°F (260°C) and can be prone to cold flow (creep). Expanded graphite can handle much higher temperatures (up to 3000°F in inert atmospheres) and exhibits better thermal conductivity and lower creep relaxation. Graphite is also more electrically conductive. PTFE may be preferred for certain aggressive chemicals or where absolute purity is needed at lower temperatures.

Q: Does Kaxite Sealing offer custom-designed or reinforced expanded graphite gaskets?
A: Absolutely. Kaxite Sealing specializes in custom sealing solutions. We fabricate gaskets to any non-standard size or shape from CAD drawings. We also produce a full range of reinforced gaskets, including:

• Tanged Metal Laminated: Graphite sheet reinforced with a perforated/stippled metal core for handling strength.
• Solid Metal Core Laminated: For high integrity, anti-blown-out applications.
• Spiral Wound Gaskets: With alternating winds of metal strip and graphite filler for high-pressure service.
• Jacketed Gaskets: Where a thin metal jacket encases the graphite for highly corrosive services.

Q: How should expanded graphite gaskets be stored and handled?
A: Store gaskets in their original packaging in a cool, dry, and clean environment away from direct sunlight, moisture, and oxidizing chemicals. Pure graphite sheets are flexible but can be brittle if bent sharply; handle with care to avoid cracking or tearing. For laminated gaskets, avoid bending the metal core. Always wear gloves when handling to prevent contamination from skin oils.