Standard stock sizes cover routine hot zone replacements. But when you are retrofitting a non-standard furnace, building a custom hot zone, or replacing boards from a foreign OEM that does not match any standard panel size, you need a manufacturer who can work from your drawings — not one who asks you to adapt your furnace to their stock.

At Expo Advanced Materials, we manufacture custom graphite insulation boards to any dimensions, any thickness, and any configuration — with complete machining capability in-house.

What We Can Manufacture

  • Flat panels — any size up to 1,200 × 800 mm in a single piece; larger assemblies from butted panels.
  • Curved boards — cylindrical hot zone sidewalls, radius-machined to fit your furnace shell.
  • Boards with machined features — electrode pass-throughs, thermocouple ports, hearth rail slots, ventilation holes, fastener counterbores.
  • Non-standard thicknesses — any thickness from 5 mm to 150 mm; multi-layer laminated boards for high-temperature applications.
  • Stepped and profiled boards — for door seals, transition zones, and heating element clearances.

Material Options

  • Standard rigid graphite felt — bulk density 0.18–0.22 g/cm³, up to 1,800 °C.
  • High-density rigid graphite felt — bulk density 0.28–0.35 g/cm³, enhanced mechanical strength, up to 2,000 °C.
  • High-purity rigid graphite felt — ash content below 50 ppm, up to 2,200 °C — for semiconductor, aerospace, medical.
  • CFC (Carbon Fibre Composite) boards — lowest thermal mass, highest strength, longest lifespan.

Tolerances We Hold

FeatureStandard TolerancePrecision (on request)
Overall dimensions±1.0 mm±0.5 mm
Thickness±0.5 mm±0.2 mm
Hole positions±0.5 mm±0.2 mm

The Ordering Process

  1. Send your drawings or dimensions — DXF, PDF, or a dimensioned sketch with all hole positions noted.
  2. We confirm material grade, tolerances, and price within 24 hours.
  3. Production: standard custom panels in 5–10 business days; complex multi-feature panels in 10–15 days.
  4. Every custom board is dimensionally inspected and supplied with a material test certificate.

Related Resources

Not sure what thickness to specify? How to Choose Insulation Board Thickness for Your Vacuum Furnace.

For stock sizes available for immediate dispatch: Graphite Insulation Board Manufacturer in India.

Complete guide: Graphite Insulation Board for Vacuum Furnaces: The Complete Guide.

Send your drawings to query@eapl.tech and we will confirm pricing within 24 hours.