The common metals are taken in a molten state from the furnaces which produce them and are cast into the forms outlined in this and the following paragraph. It must be mentioned that most of the pig iron produced by the smelting furnace is not cast into form as pig iron, but is converted into steel without leaving the molten state, and is cast as steel into ingots, billets and steel castings.

The courses followed by metals immediately after they are tapped from smelting furnaces are given in the appended table:

Metal.

How disposed of when tapped from the producing furnace.

Iron....

1.

Conveyed in the molten state as hot metal or direct metal to the mixer or retaining reservoir which supplies the Bessemer converter and the open-hearth steel furnace; or conveyed directly to these without going to the mixer. Or, when tapped from the smelter is:

2.

Cast into pigs:

(a) To be used in the foundry for making castings;

(b) To be converted into wrought iron in the puddling furnace;

(c) To be remelted for steel making as in item 1.

Copper.

.3.

Cast into:

(a) Pigs or ingots (about 50 lbs.) to be remelted for brass and other alloys;

(b) Billets for making seamless copper tubes and pipes;

(c) Cakes for rolling into sheet copper;

(d) Bars to be drawn into rods and wire.

Zinc....

4.

Cast into slabs for subsequent uses.

Lead...

.5.

Cast into:

(a) Pigs for remelting;

(b) Cakes or slabs for rolling into sheets;

(c) Bars for pressing through dies into wire and lead pipe.

Tin. .

6.

Cast into blocks for remelting.

When steel is produced it is cast into:

(1) Ingots or billets for rolling into various forms of metal stock, or for making very large forgings.

(2) Steel castings of definite form for specific uses.

The uses of the words "ingot" and "billet" are somewhat confused. In steel making, ingots are large masses of steel usually about 20 x 20 inches in section and 5 or 6 feet long, but they may be smaller and even much larger and of various shapes of cross section for particular reasons. Small ingots, about 6 x 6 inches in section and smaller, are called billets. Billets may be formed either directly by casting steel into billet moulds, or by rolling red-hot ingots down to billet sizes. Billets are usually made in specified sizes as ordered by mills which manufacture them into a particular class of articles, as tubes, rods for wire drawing, tool steel, spring material, etc.