Conventional Castable
Aluminate-cement bonded castable refractories with Al₂O₃ content from 35% to 70%. Designed for casting, pumping, and gunning applications — ideal for complex shapes, trough linings, and rapid furnace repair. Rated to 1600°C.
Available Grades & Specifications
Three alumina grades to match temperature requirements and application type. All grades are manufactured to GB/T 4513 and compatible with standard mixing and placement techniques.
General Purpose Castable
Economy-grade aluminate cement bonded castable for general boilers, heat treatment furnaces, and incinerator linings up to 1450°C. Low cost-per-tonne makes it suitable for large-volume applications and maintenance work.
- Al₂O₃ 35%, maximum service temperature 1450°C
- Bulk density ≥ 2.10 g/cm³, cold crushing strength ≥ 35 MPa
- Good flow for casting and suitable for gunning application
- Widely used for boiler linings, ash hoppers, and hot gas ducts
Medium-Grade Castable
Balanced performance castable with 50% Al₂O₃ for applications requiring improved slag resistance and higher service temperatures. Suitable for steel plant trough linings, iron runners, and non-ferrous furnace linings up to 1550°C.
- Al₂O₃ 50%, maximum service temperature 1550°C
- Bulk density ≥ 2.30 g/cm³, cold crushing strength ≥ 50 MPa
- Enhanced resistance to iron oxide and moderate slag attack
- Suitable for steel tap holes, iron runner repairs, and kiln car linings
High-Grade Alumina Castable
Premium castable with 70% Al₂O₃ for the most demanding monolithic refractory applications. Provides outstanding hot strength and slag resistance at temperatures up to 1600°C — used in steel ladle linings, petrochemical reformer inlets, and glass tank crowns.
- Al₂O₃ 70%, maximum service temperature 1600°C
- Bulk density ≥ 2.50 g/cm³, cold crushing strength ≥ 70 MPa
- Excellent hot modulus of rupture (HMOR) at 1400°C
- For steel ladles, petrochemical reformers, and glass furnace linings
Technical Specifications
| Grade | Al₂O₃ % | Max Temp | Bulk Density | Cold CCS | Water Addition |
|---|---|---|---|---|---|
| FC-35 | 35% | 1450°C | ≥ 2.10 g/cm³ | ≥ 35 MPa | 8–12% |
| FC-50 | 50% | 1550°C | ≥ 2.30 g/cm³ | ≥ 50 MPa | 7–10% |
| FC-70 | 70% | 1600°C | ≥ 2.50 g/cm³ | ≥ 70 MPa | 6–9% |
Values are post-curing at 110°C × 24h. Custom aggregate blends and particle size distributions available on request.
Industry Applications
Conventional castables are the most versatile refractory product — deployable wherever brickwork cannot reach.
Frequently Asked Questions
Standard practice is ambient cure for 24 hours, then dry at 110°C for 24 hours before beginning the firing schedule. The firing schedule should ramp slowly (typically 50°C/hour up to 350°C, then 100°C/hour) to avoid steam pressure build-up causing spalling. Firebrics provides a recommended heat-up schedule with every castable order.
Yes. All three grades can be applied by dry-process or wet-process gunning (shotcreting). Gunning is commonly used for maintenance repairs on hot furnaces and for reaching areas inaccessible to casting. Contact our technical team for nozzle water addition recommendations and equipment setup for each grade.
For lining thicknesses above 100 mm, stainless steel or heat-resistant alloy anchors (Y-type or V-type) welded to the steel shell are recommended at 200–300 mm centres. The anchor material should be compatible with the service temperature — 310 stainless for general applications, Inconel for temperatures above 1200°C. Expansion allowances must account for the anchor's different thermal coefficient versus the castable.
Related Products
High Alumina Brick
Hot face lining paired with castable backup zones for complex furnace geometries.
Insulation Bricks
Backup layer behind castable linings to reduce shell temperature and heat loss.
Custom Refractory Shapes
Precast blocks and complex shapes made from high-grade castable to your drawings.
Get a Quote for Conventional Castable
Provide your Al₂O₃ grade, application method (casting/gunning), volume, and installation zone. We'll confirm pricing and delivery within 24 hours.