C
CHEMISTRY; METALLURGY
C
CHEMISTRY; METALLURGY
C21
METALLURGY OF IRON
C21
METALLURGY OF IRON
C21B
MANUFACTURE OF IRON OR STEEL
C21B
MANUFACTURE OF IRON OR STEEL
C21B3/00
General features in the manufacture of pig-iron
C21B3/00
General features in the manufacture of pig-iron