If the ingot is not to be used for some time, it is permitted to harden, but usually it is taken to what is known as a soaking pit, where, for several days, it swelters in a high but even temperature until the entire mass of metal attains an even heat. If used immediately after stripping, the semi-solidified outer crust would crush and the still fluid inner portion would run out.
From the soaking pit the ingot is lifted by immense cranes and carried to the rolling mills, where it undergoes the various processes transforming it into steel as we know it commercially.
So many and various are these processes that no attempt will be made to describe them in detail. They vary from the rolling of a railroad rail or a fourteen-inch plate of battleship armor to a wire rod about a fifth of an inch in diameter or a sheet of tin plate such as is used in making food containers.
To the spectator all these different processes are interesting and fascinating. Entering the mill at one end the red-hot ingot is gradually reduced in size as it passes through roll after roll and brought to the required shape before being allowed to cool. In one mill we may see the mass of steel lengthened and moulded to the shape of a rail. In another, it is brought to the form of a big “I” beam for bridge or skyscraper. In another, to a slender roll of wire rod, and so on.
The more highly finished forms of steel naturally involve a further series of operations. Wire rods, for instance, are drawn through dies to smaller and still smaller sizes, and sometimes to shapes far from circular, until they become fence wire, piano wire, watch springs, and a thousand and one other products. Much of it goes to the nail mill, probably the noisiest place in the world, where it is cut, sharpened, and given a head. As stated elsewhere in this volume, the Corporation manufactures something like eleven thousand different varieties of wire products alone.
We have now followed the ore all through its journey from the mine to the finished product. But the mining of coal and its conversion into coke plays as important a part in the manufacture of steel as the mining and refining of iron. And the Corporation’s coal and coke operations are carried on a scale in harmony with the general immensity of its steel operations. In 1916 the Corporation mined 32,768,381 tons of coal and produced 18,901,962 tons of coke.