We recently noticed the fact that a new processof manufacturing iron was on its trial at Pittsburgh. This process we stated consisted in obviating the necessity of puddling, by mixing pulverized ore with the crude metal as it runs from the smelting furnace. The process is conducted at the works of Messrs. Shoenberger at the above city, and is the invention of Mr. Ellershausen. We alluded to the feet that we had obtained and tested specimens of the iron thus produced and found them of fair quality though slightly red-short, and promised to give the details of the process as soon as they could be obtained. The following is a description of this new method, extracted from The New York Times: " The process consists in the conversion of crude cast iron, as it runs from the smelting furnace, into wrought iron, by the simple admixture of granulated iron ore.. It is carried out at the works of Messrs. Shoenberger, at Pittsburgh, in thejfol-lowing manner: On the casting-floor of the smelting furnace, a cast-iron turn-table, about eighteen feet in diameter, is revolved on rollers by a small steam engine. Upon the outside edge of the table stand a row. of cast iron partitions, forming boxes, say twenty inches wide and ten inches high, open at the top. Just above the circle of boxes stands a stationary, wide-mouthed spout, terminating in tho tap hole of the furnace. When the'furnace is tapped the liquid iron runs down this spout, and falls out of it in a thin stream into the boxes as they slowly revolve under it, depositing in each a film of iron say one-eighth of an inch thick. But before the fall of melted iron reaches the boxes it is intercepted, or rather crossed, at right angles, by a thin fall of pulverized iron ore, which also runs out of a wide spout from a reservoir above. These two streams or falls are of about equal volume, say onequarter of an inch deep and twenty inches wide. A workman, with a bar in the tap hole, regulates the stream of iron, and the iron spout from which the liquid metal falls into the boxes is removable ; other spouts, previously coated with loam and dried, being attached to a common revolving frame, so as to be ready for use when the loam covering of the first becomes cracked or removed. " The thin layers of iron and ore soon chill and solidify, so that by taking away the outer partition of the boxes (which form the rim of the turn-table) they may be removed in cakes of the size of the boxes, and weighing about two hundred pounds each. Four of these cakes or blooms are put into a reverberatory puddling or heating furnace, and raised to a bright yellow heat. They will not melt at this heat, but become softened so as to be easily broken up with a bar. The four blooms are formed, in the furnace, by the " rabble" of the workman, as in ordinary puddling operations, into eight balls. The balls are brought out, one after another, squeezed in the ordinary "squeezers" to expel the cinder and superfluous ore, and then rolled into wrought-iron bars, which are now ready for market, or for further reduction into smallerfinished forms. " The chemistry of the operation is as follows: The crude cast iron contains say five per cent of carbon and two per cent of silicon, and more or less sulphur, phosphorus, and other impurities. In the Bessemer process, the oxygen of the air, blown into the liquid iron, combines with this carbon and these other impurities, and not only removes them, but leaves the pure iron in a liquid state, from which it can be cast into homogeneous masses of any size. In the puddling process, the oxygen of the air and of the ore or other " fettling" put into the furnace with the iron, combines with and eliminates the impurities, which are afterward squeezed out of the pasty mass by the squeezers and rolls. This process is long and comparatively expensive, because the mixture of oxygen or oxygen-bearing substances is not made intimate with the iron except by long stirring, which is not only skillful, but exhausting work. "In the Ellershausen process the oxygen of the ore or oxide of iron (magnetic oxide is preferred) combines with. the carbon and impurities, eliminssfeg them as in the puddling process, and the iron of the ore increases the product. The chemical combination of the ore and the liquid crude iron appears to take place partly at the time of their contact when falling and lying upon the turn-table, and partly where the reheating occurs in the furnace. It seems impossible that a reaction which is so violent in the Bessemer process, and so prolonged in puddling, sho*$4 'fake place so quickly and quietly in the new process, but the fact that Jhe cakes of iron and ore do not melt by subsequent heating, as cast iron would proves that Sluaftture is changed by the first contact Kf'the we. The remcrenl of sulphas? apdl of phosphorus also jems more ttop-ongh than in the othor processes. Analyses at different stages of the operation will throw more light on this question. " The remarkable feature of the Ellershausen process is that absolutely no skill is required to carry it out. The proportion of ore mixed is intended to be about thirty per cent, but if too much is added, it is readily squeezed out with the slag, and seems to do no harm. The subsequent heating occupies about half an hour. " Puddle bar," the product obtained from the first rolling of the product of the puddling furnace is never marketable or finished iron. It is usually very ragged and unsound, and requires subsequent piling, reheating, and rerolling, to expel the impurities, and to give it soundness and solidity. The new process appears to produce merchantable iron at the first rolling, and at Pittsburgh, from a very inferior pig iron, made of one-half sulphurous Canada ores, and one-quarter Lake Superior and one-quarter Iron Mountain ores. " The thoroughness and rapidity of the purification by this process, evidently depend on the intimacy of the mixture of iron and ore. This intimate mixture is also the essence of the Bessemer process. In fact, to Mr. Bessemer's original apprehension of this idea of intimate mechanical mixture, the greatest modern improvements in the iron manufactures are due." The saving in coal was stated to us as averaging about six dollars per ton. The Times, from which the above was taken, states that it will amount to from ten to thirty dollars per tun, according to the materials used arid the form of product required. We do not believe such a saving can be made, but events may prove us in error upon this point. As to the production of merchantable iron at first rolling, the article above quoted from is calculated to mislead, unless a great improvement has been made since we were at Pittsburgh a few months since. At that time the iron, although not puddled, was rolled more than iron usually is by the old method, although it was done at a single heat. The principles upon which the Ellershausen process is based are undoubtedly sound, but we are inclined to wait for further developments before admitting as much as is claimed for it. Steel for Gravers A correspondent writes us that he finds difficulty in getting steel sufficiently hard and tongh to stand, without leaving the graver too large at the cutting point. The tools referred to are used for the graduation of squares. He suggeststhat the steel described recently in our paper, entitled " New Steel," would be nseful for this purpose. This steel has not, so far as we can ascertain, been introduced into, this country yet. If it has, parties interested would do well to advertise it in our; 114 columns. We arc in receipt of inquiries about it which we ; cannot answer.
This article was originally published with the title "The Ellershausen Process of Manufacturing Iron" in Scientific American 20, 8, 113-114 (February 1869)