|  | C |
SECTION C — CHEMISTRY AND METALLURGY

METALLURGY

|  | C21 |
METALLURGY OF IRON

|  | C21B |
MANUFACTURE OF IRON AND STEEL

|  | C21B |
Note(s) This sub-class covers the pretreatment of iron ores, production of pig-iron, blast furnaces, and air heaters.

|  | C21B 1/00 |
Pretreatment of iron ores of ferrous material for the production of iron (pretreatment of ores in general Fulltext... Hierarchy... Expanded...C22B; washing and separating of ores Fulltext... Hierarchy... Expanded...B03; furnaces, sintering apparatus Fulltext... Hierarchy... Expanded...F27B)

|  | C21B 1/02 |
· | Methods of roasting (Fulltext... Hierarchy... Expanded...C21B 1/10 takes precedence)

|  | C21B 1/04 |
· | Removing sulphur, phosphorus, arsenic, other than by roasting

|  | C21B 1/06 |
· | Partial reduction, i.e. to a lower state of oxidation

|  | C21B 1/08 |
· | Agglomerating, binding, or briquetting iron ores, or intermediate products, e.g. flue dust

|  | C21B 1/10 |
· · | Sintering

|  | C21B 1/12 |
· · · | in tunnel furnaces

|  | C21B 1/14 |
· · · | in shaft furnaces

|  | C21B 1/16 |
· · · | in rotary furnaces

|  | C21B 1/18 |
· · · | in other apparatus, e.g. pots, sintering machines

|  | C21B 1/20 |
· · | Binding or briquetting

|  | C21B 1/22 |
· · · | with binders

|  | C21B 1/24 |
· · · · | inorganic

|  | C21B 1/26 |
· · · · | organic

|  | C21B 1/28 |
· · · · · | with carbonaceous material for the production of coked agglomerates

|  | C21B 1/30 |
· · · | of ferrous waste or alloys

|  | C21B 3/00 |
General features in the manufacture of pig-iron (mixers for pig-iron Fulltext... Hierarchy... Expanded...C21C 1/06)

|  | C21B 3/02 |
· | by applying additives, e.g. fluxing agents

|  | C21B 3/04 |
· | Recovery of by-products, e.g. slag

|  | C21B 3/06 |
· · | Treatment of liquid slag (slag wool Fulltext... Hierarchy... Expanded...C03B; slag stones Fulltext... Hierarchy... Expanded...C04B)

|  | C21B 3/08 |
· · · | Cooling slag

|  | C21B 3/10 |
· · · | Slag pots; Slag cars

|  | C21B 5/00 |
Making pig-iron in the blast furnace

|  | C21B 5/02 |
· | Making special pig-iron, e.g. by applying additives, e.g. oxides of other metals

|  | C21B 5/04 |
· | Making slag of special composition

|  | C21B 5/06 |
· | Using top gas in the blast furnace process (in coke ovens Fulltext... Hierarchy... Expanded...C10B)

|  | C21B 7/00 |
Blast furnaces (lifts associated with blast furnaces Fulltext... Hierarchy... Expanded...B66B 9/06)

|  | C21B 7/02 |
· | Internal forms

|  | C21B 7/04 |
· | with special refractories (refractory materials Fulltext... Hierarchy... Expanded...C04B)

|  | C21B 7/06 |
· · | Linings for furnaces

|  | C21B 7/08 |
· | Top armourings

|  | C21B 7/10 |
· | Cooling; Devices therefor

|  | C21B 7/12 |
· | Opening or sealing the tap holes

|  | C21B 7/14 |
· | Discharging devices, e.g. for slag

|  | C21B 7/16 |
· | Tuyères

|  | C21B 7/18 |
· | Bell-and-hopper arrangements

|  | C21B 7/20 |
· · | with appliances for distributing the burden

|  | C21B 7/22 |
· | Dust arresters

|  | C21B 7/24 |
· | Test rods or other checking devices

|  | C21B 9/00 |
Stoves for heating the blast in blast furnaces

|  | C21B 9/02 |
· | Brick hot-blast stoves

|  | C21B 9/04 |
· · | with combustion shaft

|  | C21B 9/06 |
· · | Linings

|  | C21B 9/08 |
· | Iron hot-blast stoves

|  | C21B 9/10 |
· | Other details, e.g. blast mains

|  | C21B 9/12 |
· · | Hot-blast valves or slides for blast furnaces (valves in general Fulltext... Hierarchy... Expanded...F16K)

|  | C21B 9/14 |
· | Preheating the combustion air

|  | C21B 9/16 |
· | Cooling or drying the hot-blast

|  | C21B 11/00 |
Making pig-iron other than in blast furnaces

|  | C21B 11/02 |
· | in low shaft furnaces

|  | C21B 11/06 |
· | in rotary kilns

|  | C21B 11/08 |
· | in hearth-type furnaces

|  | C21B 11/10 |
· | in electric furnaces

|  | C21B 13/00 |
Making spongy iron or liquid steel, by direct processes

|  | C21B 13/02 |
· | in shaft furnaces

|  | C21B 13/04 |
· | in retorts

|  | C21B 13/06 |
· | in multi-storied furnaces

|  | C21B 13/08 |
· | in rotary furnaces

|  | C21B 13/10 |
· | in hearth-type furnaces

|  | C21B 13/12 |
· | in electric furnaces

|  | C21B 13/14 |
· | Multi-stage processes

|  | C21B 15/00 |
Other processes for the manufacture of iron from iron compounds (by electrolysis Fulltext... Hierarchy... Expanded...C22D 1/24)

|  | C21B 15/02 |
· | Metallothermic processes, e.g. thermit reduction

|  | C21B 15/04 |
· | from iron carbonyl