Reinforced Graphite Gasket

Product overview

What is a Reinforced Graphite Gasket?
A reinforced graphite gasket is manufactured from high-purity flexible (expanded) graphite sheet that is laminated or combined with a reinforcing metallic element — typically a thin stainless-steel foil layer, perforated steel insert, wire mesh or a tanged (hooked) stainless core. The reinforcement raises crush strength, improves bolt load distribution and reduces creep/relaxation compared with unreinforced graphite sheets, while preserving graphite’s excellent thermal and chemical resistance.

A reinforced graphite gasket is a flexible graphite sheet strengthened with a metal insert (stainless-steel foil, wire-mesh, or tanged core) to improve compressive strength, blow-out resistance and dimensional stability. Ideal for high-temperature and chemically aggressive services where a pure graphite sheet needs extra mechanical support.

Common aliases / alternate names

• Reinforced graphite gasket

• Foil-inserted graphite gasket (stainless foil insert)

• Tanged graphite gasket / tang-insert graphite

• Wire-mesh reinforced graphite gasket

• Flexible graphite gasket with metal insert

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Construction & material options

Typical constructions

• Foil-inserted: flexible graphite laminated to a 0.05–0.2 mm stainless-steel foil (commonly 304/316). Good for moderate bolt loads and improved strength.

• Tanged insert: stainless steel core with stamped tangs that mechanically lock graphite layers — high retention and blow-out resistance.

• Wire mesh / perforated steel inserts: dispersed reinforcement across the sheet for higher pressure and bolt-load demands.

Materials

• Graphite: ≥98% carbon, flexible/expanded graphite for chemical and thermal stability.

• Metal inserts: SS304, SS316, nickel, or other alloys depending on corrosion resistance needs.
  Specify alloy and graphite purity when ordering.

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Performance & service limits

Temperature

• Oxidizing (air): typically up to ~450–550°C depending on product and insert; under inert/non-oxidizing conditions graphite withstands much higher temperatures.

Pressure / bolt load

• Many reinforced graphite sheet designs are used effectively up to 100–200 bar in engineered applications (application dependent on flange class and gasket form).

Chemical compatibility

• pH range 0–14 for many graphite/metal combinations; excellent resistance to acids, alkalis and hydrocarbon service. Always confirm compatibility for aggressive oxidizers or halogens.

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Standards, forms & specification notes

• Standards: Commonly supplied to ASME B16.21 (cut-gasket sizing) and manufactured to industry best practice. Request material test certificates and compliance statements.

• Forms: Full-face (FF) and inner-bolt-circle (IBC) hole patterns per ASME/DIN; cut rings for pipe flanges; custom shapes for heat exchangers, valves and vessels.

• Typical thicknesses available: 0.5 mm (0.02″) up to 6.4 mm (1/4″) — most common stock thicknesses: 0.5 mm, 1.0 mm, 1.5 mm, 2.0 mm, 3.2 mm (1/8″).

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Typical sizes & stock listing

We keep ASME NPS sizes in stock for quick delivery; custom CAD/cut-to-size orders welcome.

Common NPS stock list (examples): ½”, ¾”, 1″, 1½”, 2″, 3″, 4″, 6″, 8″, 10″, 12″ — available as FF or IBC cut gaskets to ASME B16.21 dimensions for Class 150/300/600 flanges. (Exact ID/OD follows ASME B16.21; specify flange standard and class when ordering.)

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Why choose reinforced graphite

• High temperature tolerance with excellent thermal stability.

• Improved mechanical strength & blow-out resistance compared to unreinforced graphite.

• Excellent chemical compatibility across a wide pH range.

• Low creep and reduced bolt relaxation when correctly specified and installed.

• Customizable reinforcement (foil, tangs, mesh) to match bolt load and vibration conditions.

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Comparison table — reinforced graphite vs other common gasket types

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Installation & best practices

• Surface finish: flange faces should meet recommended roughness for graphite gaskets (too smooth can reduce friction; too rough can cause embedment).

• Bolt tightening: use manufacturer torque charts adjusted for gasket thickness and flange class; tighten in star/cross pattern. Re-torque only when specified.

• Orientation & handling: avoid folding; do not overtighten (risk of metal insert damage); check for foreign particles on flanges that can puncture graphite.

• Storage: store flat, dry and away from oxidizing process chemicals to preserve graphite integrity.

Design decision check (mini-flow): If you need high temperature + high mechanical retention → consider tanged or wire-mesh reinforced graphite. If moderate loads and corrosion resistance priority → foil-insert may be sufficient.

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Typical failure modes & mitigation

• Creep/relaxation leakage: mitigate by using proper bolt preload and reinforced core when high bolt-load is expected.

• Oxidation / burn in air at high temp: use protective coatings or limit maximum oxidizing-air exposure; inerting may be needed for extreme temperatures.

• Corrosion of steel insert: specify SS316 or nickel if chloride/acid service threatens SS304.

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FAQ

Q1 — What is the difference between foil-inserted and tanged reinforced graphite?
A: Foil-inserted gaskets use a thin metal foil laminated to the graphite to add strength; tanged inserts have mechanical tangs that lock graphite layers to a steel core for higher retention and blow-out resistance. Choose tanged for high vibration/bolt loads.

Q2 — What temperature and pressure can reinforced graphite handle?
A: Typical oxidizing-atmosphere limits are ~450–550°C (product dependent); pressure capability varies with flange class and insertion type — engineered designs commonly cover up to 100–200 bar in select constructions. Always verify with the product datasheet.

Q3 — What info do you need for a quote?
A: Provide flange standard (ASME/DIN), NPS/DN, class (150/300/600/etc.), gasket form (FF or IBC), thickness, and required insert type (foil/tang/mesh) and alloy. Attach drawings for custom parts.

Q4 — Can reinforced graphite be used for steam?
A: Yes — reinforced graphite is widely used in steam services (ensure the chosen grade is appropriate for the steam temperature and any oxidation risk).

Q5 — Are there emission or fugitive-emission considerations?
A: Flexible graphite with proper metallic reinforcement can provide low fugitive emissions when installed correctly — request certified low-emission grades if required by regulation.