Some typical specifications of Indian refractories commonly used in the furnaces and kilns in steel, cement, non-ferrous metals and glass industries are given blow. These are illustrative and do not cover the full range of products and some of the improved items which have been recently developed.

CONVENTIONAL CASTABLES
CHEMICAL PROPERTIES
Al2O3(%)	60 - 65	90 Min	95 - 97
SiO 2 (%)	25-30	0	0.2
Fe 2 O3 (%)	0.7	0.8	0.15
PHYSICAL PROPERTIES
Hot Face Temp. (°C) (Max)	1650	1750	1800
Grain Size (mm) (Max)	3	5	6
B.D. Dried (g/cc)	2.2 - 2.4	2.9	2.6 - 2.8
C.C.S. (Kg/cm²)
Dried at 110°C	350 - 550	1000 Min	550 - 650
Fired at 1000°C	200 - 250	0	450 - 550
Fired at 1100°C	0	550 Min	0
Fired at 1300°C	0	850 Min	0
Fired at 1450°C	300 - 400	0	700 - 900
PLC (%)
Dried at 110°C for 3hrs	0	0	0
Fired at 1000°C for 3hrs	-0.2	0	±0.2
Fired at 1450°C for 3hrs	-0.4	0	±0.5
Fired at 1550°C for 3hrs	0	±0.7	0
Recomended water addn. (%) by weight (Legend 1550°C)	9 - 11	4 - 5	8 - 10

LOW CEMENT CASTABLES
CHEMICAL PROPERTIES
Al2O3(%) (Min)	45.0	70.0	90.0	94.0
Fe 2 O3 (%) (Max)	0.8-1.0	1.5	1.0	0.3
PHYSICAL PROPERTIES
Refractoriness (Orton) (Min)	32	36	37	+40
at temp (°C)	1717	1804	1820	1900
Maximum Service temp. (°C)	1550	1600	1700	+1800
B.D. Dry (gm/cc) (Min) at 110°C	2.3	2.7	3.05	3.1
C.C.S. (Kg/cm²)
at 110°C	700	750	950	1000
at 800°C	800	800	1100	1050
at 1100°C	900	900	1150	1100
at 1500°C	1000	0	0	0
at 1550°C	0	1000	1200	1250
PLC (%) (Max)
at 800°C	±0.2	±0.2	±0.2	±0.2
at 1100°C	±0.3	±0.3	±0.3	±0.3
at 1500°C	±1.0	0	0	0
at 1550°C	0	±1.0	±0.6	±0.5
% Water required for casting	4.5 - 5.0	4.0 - 4.6	3.5 - 4.0	3.8 - 4.3
Maximum grain size (mm)	6	6	6	6