HR Delta Roof Castable is an Ultra-Low Cement, Vibro casting material used in the application of roofs or overhead linings of Industrial furnaces like Electric Arc Furnace (EAF), Conarc Furnace and Vacuum Degasser Furnace (VD). It helps improve the performance and service life of furnaces by reducing energy loss, good corrosion resistance, enhancing heat transfer, and preventing hot spots. It is designed to withstand the extreme conditions and thermal stresses encountered during the Steel melting process.

Hazira Refractory developed its version of Delta roof castable in 2016 with its first trial in Essar steel (now AM/NS). Since then, we have dedicated significant efforts to enhance the refractoriness of the castable, making it a cornerstone of our research and development endeavors.

Salient Features:

  • PCPF center portion (made as per requirement) of the roof delta for longer life by reducing erosion.
  • Vibro casting material (easy to cast) having good volume stability.
  • Excellent thermal shock resistance.
  • High temperature resistance up to 1700°C.
  • Resistance to chemical attacks and corrosive elements.
  • With right amount of water intake and proper preheating after casting procedure it can give excellent strength.
  • Controlled curing helps in developing hydraulic bond.
HR Delta roof castable used for casting VD ring at AMNS

Hazira Refractory Works Pvt. Ltd.

HR Delta Roof Castables

Equivalent to


  Brand Name HR Delta Roof Castable HR Delta Roof Castable SPL Testing Procedure
  Type of Material High Alumina Aggregate based Ultra Low Cement Castable with Cr2O3 and Steel Fibre WTA, BFA Based Ultra Low Cement Castable with Cr2O3 and Steel Fibre
  Grain Size 0 – 10 mm/As per requirement 0 – 10 mm IS 10570 Ref.1528 XIV
  Installation Vibration Vibration
  Bond Type Hydraulic Hydraulic
  Max Service Temp. 1700°C 1750°C IS 10570 Ref: 1528 Part I
  B. D (gm/cc) 110°C/24 hrs. 2.90 Min 3.20 Min IS 10570 Ref: 1528 Part XII
  Water Required for Casting 4.5 – 6.0 % 4.0 – 5.5 % IS 10570
Cold Crushing Strength, Kg/Cm2  
  Drying at 110°C/24 hrs. 300-500 500-800 IS 10570 Ref: 1528 Part IV
  Firing at 1550°C/3 hrs. 700-900 900-1100 IS 10570 Ref: 1528 Part IV
Chemical Analyses: – (%)  
Al2O3   : 83.00 Min. 88.00 Min. IS 1527/12107
Fe2O3  : 1.0 Max. 0.3 Max.
Cr2O3 : 3.00 Max. 4.00 Max.
CaO  : 1.50 Max. 1.50 Max.
Steel Fibre  SS304 Additional Max .2.0% Additional Max. 2.0%
Permanent Linear Change, %  
  Fired at 1000°C/3hrs. ± 0.3 Max ± 0.1 Max IS 10570 Ref: 1528 Part VI
  Fired at 1550°C/3hrs. ± 0.8 Max ± 0.5 Max
  Shelf Life 3 Months 3 Months

Packing: 25 Kg bags in 1MT Jumbo Bag / Loose material in 500 Kgs. Jumbo Bag.

Delivery State: Dry

The data shown are based on average results on production samples and are subject to normal variation on individual tests hence cannot be taken as specification. Max and min. values are given separately for testing purpose.

Note: Water requirements indicated are based on laboratory test conditions. Actual water requirement may vary subject to site conditions. The properties shown are for vibratory cast material only unless specified otherwise. All values are based on test results on standard bars of size 160x40x40 mm. Test methods are guided by and based on various Indian Standards (IS).