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use of metal, as it has done abroad, and is beginning to do here; and there are thousands of wooden bridges on our railways and highways which must soon be replaced by metal; so that for these two large uses, not to speak of general machine-construction, there is growing up a vast market for a better material than iron. Excellent pig, for the production of cheap steel, is obtainable in all parts of the country, and ferro-manganese, upon which important qualities of constructive steel depend, is now cheap enough to warrant its general use. In short, with every facility for making the product so largely needed here and so largely used abroad, with the best steel works in the world, and working organizations in them which have increased product and decreased cost in a remarkable degree, we are devoting more concentrated action to schemes for preventing over-production, than we are to adapting grades and shapes of produet to the various constructive uses, and to teaching artisans how to heat, shape, and apply them.
The remedies for this state of things are various and obvious, and are indicated in the foregoing statement of the case.
1. It is undoubtedly, the policy of every Bessemer works, whether it has the machinery for rolling merchant-steel or not, to make, from time to time, experimental charges of high-quality steel, both hard and soft, so as to learn the proper ingredients and treatment. As such steel should be better than the average make, it can be disposed of for rails, if it is of the right grade, and if of softer or harder grades, what little would be made experimentally could be sold in one place or another. There might be no immediate profit in it, but it would give the maker knowledge of his resources, facts about cost, experience in treatment, and confidence in his ability ; in short, it would put him in a position to take and execute orders. Steel-makers cannot expect a very brisk demand for materials which they do not know whether they can make or not, nor what they will cost, or be like when they are made. An equally great advantage of this experimental steel-making would be an opportunity to test the exact value of their new products in tension, compression, and elasticity. I have seen Bessemer plate made and tested at Terrenoire, out of common Bessemer pig and ferro-manganese, which stretched 19 per cent., and had but 0.16 per cent. of carbon. Some crude Bessemer plate, that I saw made and had analyzed, stood every mechanical test, and had 0.21 carbon, 0.029 silicon, and 0.054 phosphorus, which shows what may be done by selecting good materials. If our present pigs are not sufficiently siliconized to blow hot, the addition of manganese in the vessel, in the shape of good spiegel, will answer the same purpose, and help rather than harm the product. The reason why our Bessemeç men do not make soft steels and those adapted to a larger range of uses, is because they do not try. But they must try and succeed, and know what they can guarantee, before they can get orders.
2. It is, also, obvious that Bessemer steel makers should increase their facilities for turning out the various shapes required, and for putting rail-ends and bloom-ends into marketable forms. Probably, a stand of billeting-rolls attached to the rail-train, a 14-inch train and direct engine and a 9-inch train belted from the same engine would best cover all up to rail-sizes. Judging from what the one or two works are doing, which have these facilities, one or the other of these small trains should very soon be kept busy on special steels and reworking rail-ends. Probably, the best means of re-rolling old steel rails and rail-ends is the very ingenious device of Edwards & Rogers, of Cleveland, -placing the grooves at an angle with the axes of the rolls. The whole rail-end can thus be utilized, while slitting off the flange and stem makes pieces that are too short for economical use. Re-rolling old steel rails and long ends into smaller rails is done successfully abroad. Even small pieces may be utilized better than by remelting, if they are of proper grade and sound
The Troy Works, for instance, are making steel cut-nails, which will drive through an oak plank and clinch.
The large use of steel for etructural purposes, however, will be in bars, which will require a 21 to 21-inch train, such as angles and small channels, I-beams and deck-beams, and large flats, rounds and squares. To change the rolls of a rail-train to fill orders, which would necessarily be small at first, for this kind of work, would be very expensive. But a couple of stands of rolls on the end of a railtrain could be changed as often as necessary, without interfering with the regular rail-production. The same stands would take the billeting-rolls before mentioned. It is probable that boiler-plates can be made cheaper and better in the long run by the Martin or by the crucible processes, but ship, bridge and tank-plates are successfully made by the Bessemer process. The existing bloomingtrains can, I believe, be changed from time to time into excellent and fast-working plate-trains by the mere substitution of suitable rolls and fixtures. This feature was considered in the original design of the mill. 3. It will also be necessary for steel-makers to take the initiative
in practicing, perfecting and disseminating the new art of working steel for structural purposes. The high degree of success which attended the treatment and use of steel in the French ships referred to, was due to an elaborate series of experiments, before and during their construction, on the injury done to plates, bars and beams by hardening, and the remedies-hardening, not by cooling only, but by pressure, as by punching, shearing and cold hammering. It has not, probably, occurred to many boiler-makers, who could do nothing with these grades of steel, and so have condemned steel altogether, that shearing and locally hammering plates puts them in a condition similar to that produced by cold-punching, which reduces the strength of the parts above 20 per cent. These injuries, bowever, are entirely local, although their effects, if not remedied, may become general. It has been demonstrated at the Barrow Works (as set forth by the manager, Mr. Josiah T. Smith, in a late paper before the Institute of Civil Engineers), and most completely proved by these French experiments, that the injury done to steels of railgrade and below, by cold-punching, is confined to the skin of the hole ( 17 7 inch thick in the French test), and that this injury is only hardening by pressure, which may be completely removed by tempering or annealing, or by reaming out this thin ring of hardened metal. The same is true of shearing; the hardened skin may be removed by planing, or restored by annealing. The Bessemer and Martin steels employed were not the softest grades; they had at least 0.25 carbon, and stood 30 tons tensile strain. They were easily hardened, and readily acquired dangerous internal strains ; yet, they were made so completely tractable by proper treatment, that they did not fail in manufacture as often as iron did, and gave promise of vastly longer endurance in service. With proper appliances, these necessary additions to ordinary iron-working processes need add but little to the cost of construction. There are still other features of the treatment of steel, especially the effects of beat, which form an important feature of this new art. I will omit its further consideration at this time, from the fact that we are to have a valuable paper, at another session, which will present this subject in detail.
The adaptability of steel to constructive purposes was specially shown in stamped work, such as pieces shaped like a low-crowned hat, of which seven hundred were produced, without losing one, while not one good piece could be stamped out of iron. The fact that steel crystallizes less than iron, by heating without working, and that steel plates have practically the same strength with and across the "grain,” were also demonstrated. The conduct and result of these experiments have been published by M. Barba, and are republished by Van Nostrand in New York.
4. But the advantages of steel as a constructive material, and of its improved treatment, cannot be monopolized by the present steelmakers. There are many iron, merchant and rail-mills, now short of work, and likely to lose business every year, as steel is developed, which have nearly all the appliances for working up steel into shapes for implements and structural uses. Such works, abroad, and, to some extent, here, are insuring the utilization of all this machinery and the permanence of their business by working their way into the steel manufacture by means of the open-hearth furnace. The Siemens-Martin process has, in such cases, the advantage of working economically on a small scale. Where it is best carried out, the product is cheap enough to warrant its substitution for iron in a large number of uses, and it is particularly economical in that the raw material employed may be largely scrap-iron and steel, of good quality, if rich ferro-manganese is used instead of spiegeleisen. Martin steel rails, in successful service in France and Russia, contain 0.38 of phosphorus, neutralized by 0.75 to 1.00 of manganese, which replaces the usual carbon. Of carbon, there is but 0.12 per cent.
5. Finally, one of the most obvious and important methods by which steel-makers can promote, not only the adaptation of better materials to structural uses, but the increased use of iron and steel structures, is to aid in the government-tests of metals, which have recently been inaugurated. Many thousands of tons of iron are annually put into bridges and ship-frames, for instance, when bridge and shipbuilders know and admit that steel is stronger and probably better in every way; but they are afraid to use it because they do not know just what the strength, elasticity and ductility of the various grades are. In default of such knowledge, they will take no risks. Now, this is just the knowledge which this government, commission will supply. If steel-makers will take hold of the matter heartily and make it their business to supply specimens of various grades, and to contribute in all ways to the thoroughness of the investigations, they will benefit themselves even more than they will serve the public. This commission intends to avoid the mistake which has made similar attempts, heretofore, of partial and limited value—the mistake of ascertaining only the physical qualities of
metals, the chemical constituents of which are practically unknown. They intend to determine what it is, not only in composition, but in treatment, that makes iron and steel good or bad, or well or illadapted to uses in building and in the arts. This information must be of the greatest value to both iron and steel-makers. And the final result must inevitably be, not only the adaptation of better materials to current uses, but the vastly increased employment of both iron and steel for new uses.
In conclusion, while it cannot be denied that the foregoing criticisms are applicable in more than a majority of cases, it would be not only ungracious, but unfair, to put forward their objects as representative and characteristic of American practice and management. Our economies, in some departments, have been remarkable, while our general steel works and rolling-mill practice is, on the whole, superior to that abroad. While the introduction of economical millengines is making slow but measurable headway here, the increasing use of reversing-engines in England is a step to the rear. The gas-furnace and the utilization of waste heat are quite as generally employed at home as in other countries.
In this connection, I cannot close these remarks without bearing testimony to the gallant manner in which the commercial promoters of our early Bessemer works poured out money and encouragement to us, who were so long floundering in the slough of technical uncertainties. I refer especially, but by no means exclusively, to the three establishments which first resisted the upper and nether millstones of inadequate professional knowledge and popular prejudice against steel,—the works at Troy, Cleveland, and Harrisburg. And it is with a feeling equally of pleasure and of justice that I also refer to the remarkable production of steel, and to the notable economies in its manufacture, which have been accomplished by the technical knowledge, the workfulness and the common-sense of the superintendents of our various steel-works. Let shareholders and directors, remembering the outcome of the troublous past, bear in mind what results the future should bring forth, when technical management of this quality is reinforced by that system of improvements which this paper has but too inadequately set forth.