REBO is Your Mullite Insulation Solution Partner
REBO goes beyond supplying bricks, we provide complete thermal insulation solutions built around your specific furnace and kiln requirements. From a single grade to a complete insulation system, REBO is your reliable partner from specification to installation.
Our offering covers the full project scope: grade selection and technical consultation, custom sizing and cutting, compatible refractory mortars and castables, lining design support, and after-sales technical assistance. Whether you are building a new furnace or upgrading an existing lining, REBO ensures every component works together for maximum thermal efficiency, structural integrity, and service life.
Specification of Standard REBO K/JM Mullite Insulation Bricks
Please note that our K Series is fully equivalent to the international JM Series in terms of specifications and performance.
K-23 is equal to JM-23; K-26 is equal to JM-26; K-28 is equal to JM-28; K-30 is equal to JM-30.
| Item/Grade | K-23 | K-26 | K-28 | K-30 | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Type | A | B | C | D | A | B | C | D | A | B | C | A | B |
| Al2O3, % | ≥42 | ≥42 | ≥45 | ≥48 | ≥54 | ≥55 | ≥56 | ≥56 | ≥64 | ≥65 | ≥66 | ≥72 | ≥72 |
| Fe2O3, % | ≤1.2 | ≤1.2 | ≤1.0 | ≤1.0 | ≤0.9 | ≤0.9 | ≤1.0 | ≤1.0 | ≤0.75 | ≤0.65 | ≤0.65 | ≤0.55 | ≤0.55 |
| Bulk Density, g/cm³ | 0.55 | 0.6 | 0.8 | 1 | 0.7 | 0.8 | 0.9 | 1 | 0.8 | 0.9 | 1 | 1 | 1.1 |
| Reheating Linear Change, % | ≤-0.5 | ≤-0.55 | ≤-0.4 | ≤-0.3 | ≤-1 | ≤-0.65 | ≤-0.5 | ≤-0.5 | ≤-1 | ≤-0.8 | ≤-0.7 | ≤-0.9 | ≤-0.7 |
| Temperature*12h | 1230℃ | 1260℃ | 1300℃ | 1300℃ | 1400℃ | 1500℃ | 1600℃ | ||||||
| Cold Crushing Strength, MPa | ≥1.2 | ≥1.5 | ≥2.3 | ≥3 | ≥2 | ≥2.3 | ≥2.8 | ≥3.2 | ≥2.3 | ≥2.8 | ≥3.3 | ≥3.0 | ≥3.5 |
| Thermal Conductivity 350℃, W/(m·K) | 0.17 | 0.19 | 0.24 | 0.31 | 0.21 | 0.25 | 0.3 | 0.32 | 0.28 | 0.32 | 0.34 | 0.4 | 0.43 |
Varieties Brand of Mullite Insulation Bricks
REBO Refractory offers a comprehensive range of mullite insulating firebricks, including the JM Series (also known as the K Series), B Series, and C Series. They are designed to meet the high-temperature insulation requirements of industries across different countries and regions. JM series is the hot series.
| Grade | Max service temp. | Al₂O₃ content | Key features |
|---|---|---|---|
| JM23 | 1230 °C | 38 – 44% | Lowest density; ideal for low-temp kiln backup lining |
| JM26 | 1400 °C | 50 – 58% | General mid-temp use; low thermal conductivity; suitable for roller and ceramic kilns |
| JM28 | 1510 °C | 65 – 70% | Direct flame contact; high strength; excellent thermal shock resistance |
| JM30 | 1620 °C | 70 – 73% | Ultra-high temp; highest Al₂O₃; best strength and refractoriness |
| B4 | 1260 °C | 45 – 50% | Lightweight; low thermal conductivity; low-temp backup lining |
| B5 | 1300 °C | 50 – 55% | Balanced insulation and strength for low-to-mid temp applications |
| B7 | 1430 – 1540 °C | 65 – 70% | High-temp B grade; suitable for hot face or structural layer |
| C1 | 1300 °C | 45 – 55% | Higher density than B5; better strength for load-bearing positions |
| C2 | 1430 °C | 55 – 65% | High density; strong compressive strength; good erosion resistance |
Mullite Insulation Brick Built for High-Temperature Performance
Withstands up to 1790 °C; load-softening temp 1600–1700 °C.
Low Thermal Conductivity
Minimises heat loss; reduces furnace wall thickness.
Lightweight Structure
Density 0.6–1.1 g/cm³; reduces kiln structural load.
Survives rapid temperature; cycling without cracking.
High Mechanical Strength
CCS 70–260 MPa; stable under load at high temperature.
Chemical Stability
Low Fe₂O₃ & alkali content; resists slag and acid attack.<
Rigorous Manufacturing Delivers Superior Performance
From raw material sourcing to final delivery, every REBO refractory firebrick is built to perform in the most demanding high-temperature environments. As high alumina fire bricks manufacturers, REBO has strong manufacturing, design, and solution capacity.
REBO sources only high-purity raw materials (such as premium bauxite and kyanite). Every batch undergoes rigid chemical and physical screening before entering the production line to eliminate impurities from the very start.
Al₂O₃ ≥ 30%
Utilizing fully automated, computer-controlled batching systems to ensure micro-level accuracy in chemical composition formulas. This guarantees consistent bulk density and thermal shock resistance across all brick series.
2×168m tunnel kilns
Formed under high-tonnage hydraulic presses for maximum structural density, followed by automated CNC grinding and cutting machines to control dimensional tolerances within 1mm.
Third-party reports available
Bricks pass through scientifically regulated tunnel dryers and high-temperature kilns. The precise temperature curves eliminate internal stress, ensuring zero reheating linear shrinkage.
Mass production and custom sizes supported
Every single insulating brick undergoes a strict visual and dimensional audit. Finished products are packed on fumigated wooden pallets with corner protectors and heavy-duty shrink wrap to withstand long-distance ocean freight.
REBO maintains absolute transparency by sharing live container-loading photos, packing videos, and shipping documents (B/L) with our clients immediately upon dispatch, coupled with proactive tracking updates.
Mullite Insulation Bricks Serves Global Industries
Global Installation Sites
At REBO, our mullite insulation bricks don’t just leave the factory they go to work in some of the world’s most demanding industrial environments.
From the roaring heat of ceramic tunnel kilns in Europe to the continuous casting furnaces of steel plants across Southeast Asia, REBO mullite mullite bricks have earned their place where failure is simply not an option.
Every installation tells the same story: lower energy consumption, longer service life, and fewer unplanned shutdowns. That is not a claim it is what our customers report back from the field.
When you see a REBO aluminum oxide bricks and other bricks on-site, you are looking at the result of stringent raw material selection, precision manufacturing, and a quality system that never cuts corners.
Mullite Insulation Bricks Serves Global Industries
Shuttle kilns: sidewalls, roof arches, door panels.
Roller kilns: sidewall & roof lining in firing zones.
Tunnel kilns: kiln car superstructure & roof.
Key pairing materials: Ceramic fiber blanket/board for cold face; Dense high-alumina brick for peak-temp zones; Refractory mortar; Castable for transitions; Microporous panel [backup]
Hot blast stoves: crown & upper shaft lining
Heat treatment furnaces: roof & sidewalls
Steel ladle: backup insulation layer
Key pairing materials: Silica brick for combustion chamber; Dense fireclay brick for lower shaft; Refractory castable for burner blocks, door frames; Ladle mortar
Cement rotary kiln: Preheater calciner, kiln tail smoke chamber, tertiary air duct insulation lining
Grate cooler: Roof and sidewall insulation layer
Key pairing materials: Anti-spalling high-alumina brick; Silica-mullite brick; Alkali-resistant castable; SiC wear-resistant castable; Anorthite insulation brick
Aluminum melting & holding furnaces: Upper sidewall backup for non-contact with liquid aluminum, roof insulation layer
Carbon anode baking furnaces: Flue walls and furnace wall insulation
Key pairing materials: Anti-wetting aluminum-resistant castables; High-alumina brick; Impermeable ceramic board; Calcium silicate board
Cracking furnaces: roof & sidewall backup
Reforming furnaces: radiant box walls & flue
Carbon black reactors: shell backup layer
Key pairing materials: Dense castable for hot face; Ceramic fiber module for outermost layer; High-alumina castable; Stainless steel anchors
Regenerator chambers: checker-work & partition walls
Furnace crown: backup behind AZS blocks
Key pairing materials: Fused-cast AZS brick for working face; Silica brick · Magnesia-chrome brick; Refractory mortar
Integrated Lining Solutions Matching for Mullite Bricks
