(0)C21B:0/0:
IPC6
SECTION C - CHEMISTRY; METALLURGY
C21B
1/1
METALLURGY
C 21
METALLURGY OF IRON
C 21 B
MANUFACTURE OF IRON OR STEEL
(preliminary treatment of ferrous ores or scrap
C 22 B 1/00
; electric heating
H 05 B
)
Notes
(1)
This subclass
covers
:
-
the production of iron or steel from source materials, e.g. the production of pig-iron;
-
apparatus specially adapted therefor, e.g. blast furnaces, air heaters (furnaces in general
F 27
).
(2)
Processes using enzymes or micro-organisms in order to:
(i)
liberate, separate or purify a pre-existing compound or composition, or to
(ii)
treat textiles or clean solid surfaces of materials
are further classified in subclass
C 12 S
. [5]
3
/
00
General features in the manufacture of pig-iron
(mixers for pig-iron
C 21 C 1/06
)
3
/
02
by applying additives, e.g. fluxing agents
3
/
04
Recovery of by-products, e.g. slag
3
/
06
Treatment of liquid slag (slag wool
C 03 B
; slag stones
C 04 B
)
3
/
08
Cooling slag
3
/
10
Slag pots; Slag cars
5
/
00
Making pig-iron in the blast furnace
5
/
02
Making special pig-iron, e.g. by applying additives, e.g. oxides of other metals
5
/
04
Making slag of special composition
5
/
06
using top gas in the blast furnace process (in coke ovens
C 10 B
)
7
/
00
Blast furnaces
(lifts associated with blast furnaces
B 66 B 9/06
)
7
/
02
Internal forms
7
/
04
with special refractories (refractory materials
C 04 B
)
7
/
06
Linings for furnaces
7
/
08
Top armourings
7
/
10
Cooling; Devices therefor
7
/
12
Opening or sealing the tap holes
7
/
14
Discharging devices, e.g. for slag
7
/
16
Tuyθres
7
/
18
Bell-and-hopper arrangements
7
/
20
with appliances for distributing the burden
7
/
22
Dust arresters
7
/
24
Test rods or other checking devices
9
/
00
Stoves for heating the blast in blast furnaces
9
/
02
Brick hot-blast stoves
9
/
04
with combustion shaft
9
/
06
Linings
9
/
08
Iron hot-blast stoves
9
/
10
Other details, e.g. blast mains
9
/
12
Hot-blast valves or slides for blast furnaces (valves in general
F 16 K
)
9
/
14
Preheating the combustion air
9
/
16
Cooling or drying the hot-blast
11
/
00
Making pig-iron other than in blast furnaces
11
/
02
in low shaft furnaces
11
/
06
in rotary kilns
11
/
08
in hearth-type furnaces
11
/
10
in electric furnaces
13
/
00
Making spongy iron or liquid steel, by direct processes
13
/
02
in shaft furnaces
13
/
04
in retorts
13
/
06
in multi-storied furnaces
13
/
08
in rotary furnaces
13
/
10
in hearth-type furnaces
13
/
12
in electric furnaces
13
/
14
Multi-stage processes
15
/
00
Other processes for the manufacture of iron from iron compounds
(general methods of reducing to metal
C 22 B 5/00
; by electrolysis
C 25 C 1/06
)
15
/
02
Metallothermic processes, e.g. thermit reduction
15
/
04
from iron carbonyl
