Iron industry

“ One naturally wonders how it is possible to mine and carry these ores to the shipping ports of Duluth, Superior, Two Harbors, Marquette, Ashland, Escanaba, etc., put them aboard ore carrying boats, transport them by steam power to Milwaukee, Chicago, Gary, Detroit, Cleveland, Pittsburg, Buffalo, and the many other iron centers and convert them into iron and steel at a profit. This, of course, is only possible because of the inventive genius of man. For every operation ingenious machinery has been constructed which has brought the cost of such operations to its lowest terms. ”

“ It was only after the next great advance that we found man utilizing iron for his purposes of civilization. This metal, which with us is so common, was in those days very expensive, so much so that it could be used only for purposes of war and as the gifts of kings.
But the world was traveling fast and it was not long before the iron-carbon alloy, steel, was produced. Even so, many hundreds of years elapsed before the present wonderful age was ushered in through the great inventions of Henry Bessemer and the Siemens brothers. ”

“ Steel has no fiber and for this reason it cannot be split as was the wrought iron bar shown in the illustration of page 92.
It will have been noticed that only small amounts of iron can be refined at one time. This, indeed, has been the unfortunate part of wrought iron manufacture, for it may readily be seen that production of any such material in lots as small as a quarter ton results in labor costs which are almost prohibitive in these days of machine-made goods. Not only is the output of a furnace small but much skill and judgment are necessary for the production of a high grade product. ”

“ But obviously, the inertia of capital and labour to be overcome before the iron-producing industry can grow by a decrease of certain other industries, will prevent its growth from taking place until long after the increased ship-building industry has demanded it; and meanwhile, the growth of the ship-building industry must be limited by the deficiency of iron. A remoter restraint of the same nature meets us if we go a step further—a restraint which can be overcome only in a still longer time. For the manufacture of iron depends on the supply of coal. ”

“ It has been felt most severely in the United States; but in the United Kingdom, and in France and Germany, the iron industry has been so much depressed, all through the year, that many iron-works have been closed, and many others have been employed but a part of the time. ”

“ It will resist great shock and can be severely battered and bent without breaking. It has about 75 per cent or more of the tensile strength of mild steel and because of the cheapness of its castings the malleable iron industry has developed wonderfully. About a million tons of this product are produced here each year.
Naturally malleable iron castings are used where a material with properties intermediate between cast iron and steel will suffice. Such are castings for railroad cars, for reapers, binders, and other agricultural machines, pipe fittings, and the cheaper grades of tools. ”

“ In the midst of the insecurity, however, engendered by civil war and social changes, the pursuits of industry must necessarily have been considerably interfered with, and the art of iron-forging became neglected. No notice of iron being made in Sussex occurs in Domesday Book, from which it would appear that the manufacture had in a great measure ceased in that county at the time of the Conquest, though it was continued in the iron-producing districts bordering on Wales. ”

“ To be worked at a profit, the iron content of the ore must be high with the smallest possible amounts of undesirable impurities, particularly phosphorus, sulphur, and silica. There are, however, certain impurities which are not undesirable, for instance, lime, which will act as a flux and neutralize the effect of some of the undesirable impurities. For these reasons the prices for iron ore are based on the iron content and modified by the relative amounts of undesirable and desirable impurities. ”

“ Almost every civilized country has ore enough that it does pretty well. With many the trouble is that the ore has objectionable constituents or that supply of cheap fuel is not available. Germany has large deposits of iron ore, but until the invention of the basic Bessemer process about 1870 she was handicapped because of the high phosphorus content of her ore. The basic processes, both Bessemer and open-hearth, allow of the removal of this phosphorus during the conversion into steel, and they therefore brought Germany to the front as an iron producer. ”

“ Instead of the 66 per cent iron ores of some years ago those coming nowadays contain not much more than 59 per cent of iron and the Bessemer ores described above are getting scarcer, so that for some years practically all of the furnaces have been mixing with them as much higher phosphorus ore as could be used without pushing the phosphorus content of the mixture over the allowable limit.
We often hear people surmising what is to become of us when all of the iron ore of this planet has been used. There is no harm in taking stock of resources and in this case it does us much good. ”

“ It is so highly 75refined that it can hardly be called steel at all but is often called “open-hearth iron” or “ingot iron.” It is probably the purest iron on the market in commercial quantities to-day. While in the chemical laboratory iron of considerably greater purity can be made, for a commercial product this is remarkably pure, seldom containing more than 1⁄4 per cent of elements other than the metal, iron. ”

“ A superficial area of eight square leagues yielded some eight hundred thousand tons of iron-ore, of which two-thirds were ferro-manganese, and twenty thousand to twenty-five thousand tons of lead containing thirty thousand kilogrammes of silver. As regards the use of iron for many purposes by the ancient Britons before the Roman conquest, we may fairly, without attaching importance to the legend of ‘Milesius,’ believe that the industry may also have migrated northwards from a Spanish centre. ”

“ Of recent years, mild steel has been the great competitor of wrought iron. With marvelous energy, skill, and much capital the manufacturers of Bessemer and open-hearth steels have adapted their products very well to the needs of the iron user, while the enormous tonnages turned out in short time by use of ingenious furnaces and other devices has resulted in a low cost of production. ”

“ At the average annual rate of iron ore output in the years 1968 and 1969 the reported life span of the deposits indicates a reserve of only 133 million tons as of 1970. Whatever the actual reserves may be, domestic iron ore has had to be supplemented by imports of about 1 million tons per year from the Soviet Union and Algeria to meet the requirements of the metallurgical industry. ”

“ As the basis for its cast iron, many thousands of tons of pig iron are each year used direct from the blast furnaces. The raw materials come in railroad cars or by boat. The inspector who represents the metallurgical department enters each car and inspects the materials, taking from each a representative sample for analysis. ”

“ It happens that each time the count is taken of iron ore available and that which under future and 36better methods of working can be utilized, we find ourselves immensely better off than the previous report had made out and we have less cause to worry about the future. ”

“ That is, as soon as a vessel costing millions of dollars leaves the docks, she enters into active competition for a place on the junk pile."
The greatest improvement that can be imagined in the iron situation will be in the discovery and use of alloys or mixtures of iron with other materials. Steel, the strongest of all forms of iron, is an alloy of iron and carbon, and for various purposes these are further mixed with nickel and silicas. Many other alloys have been discovered within the last few years, and each makes possible new uses for iron requiring greater strength. ”

“ With the progress of civilisation its employment extended to many purposes unknown before; and in our times the construction of ships and buildings, of railroads and bridges, absorbs quantities which would have appeared incredible almost within the memory of living man. Hence the manufacture of iron has made more rapid progress since the beginning of the present century than in any former period of the world’s history, and even the present immense production scarcely keeps pace with a demand to which it is not easy to assign a limit. ”

“ As a commercial product, such as is used in the arts and manufactures and by the smith, it is always combined with other substances, such as carbon, silicon, and phosphorus.
Iron is distributed through the earth very widely, but not always in sufficient quantities to make its extraction from the ore profitable; consequently the ores used for the extraction of iron are somewhat limited. There are four general grades of iron ore, which are known by the following names: magnetite, red hematite, limonite, and ferrous carbonate. ”

“ New fields of iron-ore have been discovered in Germany, France, and Belgium, very analogous in point of character to those which by discovery and development, about the year 1850, in the north of England, led to the subsequent great and rapid increase of British iron production.
Second. The power of producing iron with a given amount of labor and capital has, in recent years, greatly increased. For example, the average product per man of the furnaces of Great Britain, which for 1870 was estimated at 173 tons, is reported to have been 194 tons in 1880, and 261 tons in 1884. ”

“ In the middle of the eighteenth century a process for smelting iron with coal turned out to be effective; and the whole aspect of the iron-trade was at once revolutionized. In fifty years the annual production of iron in Great Britain rose from under twenty thousand to more than one hundred and seventy thousand tons. ”

“ Economies in handling the ore, by means of steam shovels and carriers, and in transporting it by water and railroad, have enabled it to be brought to the heart of the coal and coke regions at comparatively slight expense. In the reduction of the ore and in the various processes of manufacture the American iron makers in recent times have been quick to introduce improvements discovered in other countries; and have themselves contributed important devices by which the efficiency of the labor employed in iron manufacture has been greatly increased. ”

“ It was thought, and justly, that the making of pig-iron with pit coal was a great acquisition to the country by saving the wood and supplying a material to manufactures, the production of which, by the consumption of all the wood the country produced, was formerly unequal to the demand, and the nail trade, perhaps the most considerable of any one article of manufactured iron, would have been lost to this country had it not been found practicable to make nails of iron made with pit coal. We have now another process to attempt, and that is to make BAR IRON with pit coal ”

“ Ordinary cast iron, while strong and hard enough for many purposes, still is brittle by reason of the large proportion of carbon and other impurities which it contains. These impurities may be burned out in the puddling process, and the nearly pure iron thus obtained, called malleable or wrought iron, has a toughness enabling it to resist far greater strains than cast iron can stand. Intermediate between the two irons, and containing one per cent of carbon, more or less, is still another product, steel, which may be made even more tenacious than wrought iron, or even harder than cast iron. ”

“ Whenever a rise in the price of iron stimulates the manufacture, the domestic production of iron suddenly expands, and increases with a rapidity which gives evidence of wonderful elasticity and latent strength. Twice within twenty years the production of American iron has nearly doubled in a period of three years. Twelve years ago no railroad-iron was made in the United States. In 1853 we imported 300,000 tons of rails, and in 1854 280,000 tons ”

“ Containing, as it does, a larger percentage of iron than any other source from which the metal is commercially extracted, its employment as an ore results in great economy of fuel, as well as a reduction in the proportionate costs of transport. When ores of iron require [Pg 190] to be brought from oversea places, it is obvious that those which will concentrate to the purest product possible, and which are in other respects specially applicable to the production of grades of steel of exceptional tensile strength, will have the preference. ”

“ The most extensive of them appear to have been in Sussex and Monmouthshire, in which last county there are places where the ground is in large areas covered by their cinders and refuse, and in this about 30 or 40 per cent. of iron occurs, so that for some centuries this material was found capable of being profitably reworked as a source of the metal. Iron continued to be produced in England during the middle ages with charcoal for fuel, but its export was forbidden, and whatever steel was required had to be imported from abroad. ”

“ Pig iron, which was the original basis for the manufacture of all iron and steel, is made by the reduction of iron ore in large blast furnaces, which are filled with layers of ore, charcoal or coke, and flux. By the agency of this the iron is melted out and falls to the bottom of the furnaces, is drawn out through openings for that purpose into canals, and finally into molds, where it solidifies into what are termed pigs. Prior to the invention of Sir Henry Bessemer, steel was manufactured from a pig-iron base by a tedious and expensive process of refining in furnaces adapted to that purpose. ”