K-30 / JM-30 · ASTM C155 Group 30 · 1650 °C
K-30 Insulating Refractory Bricks
Supplier and exporter from Rajkot, India. Premium IFB grade — top-of-range hot-face insulation, glass tank superstructure back-up and premium kiln linings up to 1650 °C.
- Max temp1650 °C
- Bulk density0.85 g/cm³
- CCS≥ 1.8 MPa
- Al₂O₃≈ 78%
- Standard size230 × 114 × 65 mm
- MOQ3 – 5 MT
About this product
What K-30 insulating fire bricks are — and where they fit
K-30 insulating fire bricks (also marketed as JM-30) are the highest-rated grade in the standard ASTM C155 IFB classification — Group 30. The brick is manufactured from selected high-purity alumina raw materials (~78% Al₂O₃) bonded to a porous matrix at high firing temperature. The result is a refractory brick with bulk density of 0.85 g/cm³, thermal conductivity of about 0.50 W/m·K at 1400 °C, and the load-bearing performance to operate at hot-face temperatures up to 1650 °C.
What is K-30? K-30 is the ASTM-classified premium insulating refractory brick rated for continuous hot-face service up to 1650 °C (3000 °F). It sits at the top of the standard IFB temperature range and exists for applications where the back-up insulation layer needs to survive operating temperatures that would slag or pyrochemically attack lower K-grades. The grade is denser than K-23/K-26/K-28, but still provides a meaningful insulation benefit — its conductivity is roughly one-third that of an equivalent dense 80% alumina refractory brick.
K-30 is regularly specified as the hot-face brick in glass tank superstructure and crown back-up positions, premium ceramic kiln linings, hydrogen reformer back-up insulation, and as the back-up layer behind dense corundum or 80 – 90% high-alumina hot-face bricks in steel-industry equipment. Above 1650 °C the standard IFB range no longer applies; for severe service, see specialty refractories and corundum-based alternatives.
firebrickssource.com supplies K-30 in the standard 230 × 114 × 65 mm size, plus arches, wedges, splits and machined shapes to drawing. The brick is normally packed shrink-wrapped on heat-treated wooden pallets, edge-protected, with corner boards. The grade is exported to glass-tank engineering OEMs, premium ceramic manufacturers, petrochemical EPC contractors and steel-plant refractory specifiers worldwide. For lower temperatures see K-28; for back-up board solutions see calcium silicate boards.
Technical specifications
Full property data — K-30 IFB
| Property | Value | Test method |
|---|---|---|
| Classification | ASTM C155 Group 30 | ASTM C155 |
| Max service temperature | 1650 °C (3000 °F) | ASTM C155 |
| Bulk density | 0.85 g/cm³ | ASTM C134 / IS 1528-12 |
| Cold crushing strength (CCS) | ≥ 1.8 MPa | ASTM C133 / IS 1528-4 |
| Modulus of rupture (MOR) | ≥ 1.6 MPa | ASTM C93 |
| Apparent porosity | ≥ 60 % | ASTM C20 / IS 1528-8 |
| Thermal conductivity at 1400 °C | ≈ 0.50 W/m·K | ASTM C182 |
| Permanent linear change at 1620 °C × 24 h | ≤ −1.0 % | ASTM C210 |
| Al₂O₃ content | ≈ 78 % | IS 1528-7 |
| Standard size | 230 × 114 × 65 mm | — |
| Custom sizes | Available on request — arches, wedges, splits, machined shapes | — |
*Typical certified values — actual batch values issued on the per-shipment test certificate. Values aligned with IS 1528 / ASTM C-series / EN 993 test methods.
Applications
Where to use K-30 insulating bricks
- Hot-face insulation at the upper IFB temperature range
- Glass tank superstructure back-up
- Glass tank crown back-up insulation
- Premium ceramic kiln hot-face (clean atmospheres)
- Hydrogen reformer back-up insulation
- Steam-methane reformer radiant section back-up
- Back-up behind 80 – 90% alumina or corundum hot-face
- Cracker furnace and ethylene reformer back-up
- High-temperature lab furnace lining
- Premium pyrolysis and gasifier insulation
Datasheet
Download technical datasheet
PDF with all certified properties, dimensional tolerances and applicable ASTM / IS test methods. Use this for tender attachments and procurement files.
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Frequently asked
K-30 — questions buyers ask
What is the maximum service temperature for K-30 IFB?
K-30 insulating fire bricks are classified ASTM C155 Group 30 and are rated for hot-face service up to 1650 °C (3000 °F). K-30 is the top of the standard IFB temperature range.
When should I choose K-30 over K-28?
Choose K-30 when service temperature exceeds 1540 °C, when refractoriness under load is a concern at peak temperature, or when you want the highest-alumina (~78%) IFB option. For service in the 1430 – 1540 °C window K-28 is normally the more cost-effective grade.
Where are K-30 insulating refractory bricks used?
Typical applications include hot-face insulation at the upper IFB temperature range, glass tank superstructure back-up, premium kiln hot-face for ceramics, hydrogen reformer back-up, and back-up behind dense corundum or 80 – 90% alumina hot-face.
What is the Al₂O₃ content of K-30?
K-30 has approximately 78% Al₂O₃ — the highest in the standard IFB family. This is what enables the 1650 °C rating and gives the brick its load-bearing performance at peak temperature.
Is K-30 suitable as a hot-face brick?
K-30 can be used as a hot-face brick in clean, non-corrosive atmospheres at the upper IFB temperature range. In glass-tank superstructure, ceramic kilns and clean petrochemical reformers, K-30 routinely serves as the hot-face. For aggressive atmospheres it is recommended as back-up to a denser refractory.
What is the typical MOQ and packaging?
Standard MOQ is 3 – 5 MT for stocked sizes. IFB is shrink-wrapped on heat-treated wooden pallets, edge-protected, with corner boards. One 20-foot container typically loads 14 – 17 MT of K-30 IFB depending on shape mix.
Do you provide samples and test certificates?
Yes. Samples can be dispatched on request — normally chargeable plus courier. Every production batch is tested for bulk density, cold crushing strength, permanent linear change and thermal conductivity (lot basis); a test certificate ships with the consignment.
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