Calcium Silicate Board

Why Choose 300 kg/m³ Calcium Silicate Board

✓Higher compressive strength than the 250 grade for everyday handling and load

✓Lighter than the 400 grade — lower weight on furnace structures

✓More mechanical durability than 250 under foot traffic and fixings

✓Energy-saving lining that cuts fuel use through low heat transfer

Suitable For

300 kg/m³ Specifications

Property	Value (Metric)	Value (US)
Density	300 kg/m³ ±10%	18.7 lb/ft³
Max Service Temperature	1050°C	1922°F
Continuous Service Temperature	950°C	1742°F
Compressive Strength	≥ 1.5 MPa	≥ 218 psi
Flexural Strength	≥ 0.8 MPa	≥ 116 psi
Thermal Conductivity @ 200°C	≤ 0.082 W/m·K	≤ 0.57 BTU·in/hr·ft²·°F
Thermal Conductivity @ 400°C	≤ 0.108 W/m·K	≤ 0.75 BTU·in/hr·ft²·°F
Thermal Conductivity @ 800°C	≤ 0.170 W/m·K	≤ 1.18 BTU·in/hr·ft²·°F
Reaction to Fire	A1 non-combustible	Non-asbestos

Density tolerance ±10%. Continuous service 950°C (1742°F); 1050°C (1922°F) is peak. Non-asbestos, A1 non-combustible.

Chemical Composition

Component	Unit	Value
SiO₂	%	52 Min
CaO	%	40 Min
Al₂O₃	%	0.3 Max
Fe₂O₃	%	1.0 Max
Loss on Ignition	%	7 Max

Dimensions (mm, ±2 mm)

Length × Width	Thickness (mm)
1220×1220 · 1210×1210	20 – 100
1230×1000 · 1230×500	20 – 100
1260×600 · 1000×500	20 – 100

Custom sizes on request. Supplied as flat rigid sheets, machinable to custom dimensions and shapes; thickness 20–100 mm (0.8–3.9 in).

300 vs 250 vs 400 kg/m³

Where the standard 300 grade sits between the lightweight 250 and the high-strength 400.

Grade	Weight	Strength	Typical Use
250 kg/m³	Very Light	Medium	Back-up insulation
300 kg/m³	Balanced	High	General industrial furnace
400 kg/m³	Heavy	Highest	Load-bearing / high strength

Where 300 kg/m³ Is Used

Heat Treatment Furnace

Standard lining and back-up insulation for batch and continuous furnaces.

Steel Ladle Backup

Safety back-up layer behind refractory in ladles and tundishes.

Cement Kiln Insulation

Hot-zone back-up lining for preheaters and kiln hoods.

Boiler System

Heat containment and casing insulation in boiler systems.

How to Install

Measure

Survey the surface and plan board layout and joints.

Cut

Cut to size with a saw or blade; CNC for shapes.

Anchor

Fix with studs, clips, or high-temperature adhesive.

Joint

Stagger joints and seal gaps with jointing compound.

Dry-Out

Ramp temperature gradually on first heat-up to drive off residual moisture before full service.

Frequently Asked Questions

What is 300 kg/m³ calcium silicate board?

The standard industrial grade: a rigid 300 kg/m³ board for general furnace and kiln linings up to 1050°C (1922°F), balancing light weight with ≥ 1.5 MPa (218 psi) strength.

Can it replace ceramic fiber?

As a rigid back-up or hot-face board it replaces fiber where dimensional stability, a hard surface, and machinability are needed — it holds shape and does not shed loose fibres.

How thick should the insulation be?

It depends on hot-face and target cold-face temperature; 25–75 mm is common. Use the thermal-conductivity data above, or send your conditions for a calculated recommendation.

Can it contact flame?

It is A1 non-combustible and rated to 1050°C (1922°F) peak; for direct hot-face or flame contact, design within the 950°C (1742°F) continuous limit.

How do you cut it?

It cuts cleanly with a standard hand saw or power blade and can be CNC-machined — no special tooling required.

What export packaging do you provide?

Boards are film-wrapped, edge-protected, and palletized or crated for safe international shipping.