The high-performance alternative to standard graphite — stable to 1,000°C, chloride-free, and compliant with ASME B16.20. Available up to 52" in 300, 600 and 900 LBS. Ideal for hydrogen, steam, acid and high-temperature refinery service. Supplied Globally.
Standard flexible graphite has been the industry default for spiral wound gasket filler for decades. But it has three hard limits — temperature ceiling, chloride content, and fugitive emissions — that make it unsuitable for an increasing range of critical applications in Globaln process plants.
Flexible graphite oxidises in air above 450°C, losing mass and sealing integrity over time. Thermiculite 835 maintains structural and sealing integrity to 1,000°C — making it the correct choice for reformer flanges, cracker outlet flanges, and high-temperature steam headers.
Commercial graphite contains measurable chloride levels that can cause stress corrosion cracking in austenitic stainless steel, Incoloy, and Hastelloy components over time. Thermiculite 835 is certified chloride-free — essential in pharmaceutical, semiconductor, and high-purity chemical service.
Global's environmental compliance requirements are tightening in line with international standards. Thermiculite 835 is qualified to TA-Luft and ISO 15848 fugitive emission standards — relevant for hydrogen, volatile organic compounds, and hazardous fluid service.
Global's green hydrogen mission requires gasket materials compatible with high-temperature hydrogen service. Thermiculite 835 is rated for hydrogen applications where standard graphite filler is not appropriate due to temperature excursions or material compatibility concerns.
Thermiculite 835 does not shed particles or contaminate process streams in pharmaceutical and bioprocess applications. Suitable for API manufacturing environments where product purity is non-negotiable.
Supplied with Thermiculite 835 material certification, ASME B16.20 compliance statement, and mill test certificates for all metallic components. Accepted by Globaln PSU procurement as an approved specialist filler material.
| Property | Specification | Notes |
|---|---|---|
| Filler material | Thermiculite Series 835 | High-performance vermiculite-based filler. Not graphite or PTFE. |
| Maximum temperature | 1,000°C (1,832°F) | Continuous service in air. Inert atmospheres may permit higher. |
| Chloride content | <10 ppm — certified chloride-free | Safe for austenitic SS, Incoloy, Hastelloy flanges. |
| Maximum diameter | Up to 52" (1,320 NB) | Custom sizes on request beyond ASME standard tables. |
| Pressure classes | Class 150, 300, 600, 900 LBS | 1500 and 2500 LBS on request. |
| Winding material options | 316L SS · Incoloy 825 · Hastelloy C-276 · Alloy 20 · Duplex 2205 · Titanium · Monel | Winding strip material specified separately from filler. |
| Inner ring | 316L SS standard · exotic alloys on request | Prevents inward buckling, protects filler at bore. |
| Outer ring (centering) | Carbon steel standard · 304/316 SS option | Provides bolt-circle centering and compression stop. |
| Applicable standards | ASME B16.20 · ASME B16.47 Ser A & B · EN 1514-2 | Dimensional conformance certified. |
| Fugitive emission standard | TA-Luft · ISO 15848-1 | Qualified for fugitive emission-controlled service. |
| Documentation | Material cert · MTCs all components · ASME compliance statement · Dimensional report | PSU procurement ready. |
| Delivery terms | CFR Mumbai shipping standard | Airfreight for emergency orders. |
Hydrogen reformers and naphtha crackers operate at 700–900°C with flanges that cycle thermally during start-up and shutdown. Standard graphite oxidises and sheds mass through these cycles.
Main steam lines at supercritical and ultra-supercritical power plants operate above 550°C at pressures exceeding 250 bar. Thermiculite 835 provides reliable sealing performance where graphite filler would begin degrading.
Global's expanding green hydrogen capacity requires gasket materials rated for hydrogen service at elevated temperature and pressure.
Where reactor body flanges are manufactured from Incoloy, Hastelloy, or austenitic SS, the use of graphite filler carries a long-term chloride SCC risk. Thermiculite 835 eliminates this risk entirely.
Globaln pharmaceutical API manufacturing requires gasket materials that do not contaminate high-purity process streams. Thermiculite 835's non-contaminating properties make it the correct choice over graphite in GMP environments.
NPCIL and BARC applications require fully traceable gasket materials with documentation packages. Thermiculite 835 is available with nuclear-grade material traceability for qualifying applications.
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