Attempts liave been repeatedly made to economize in time, fuel, labor, and material, in tlie manufacture of iron, by wold-ing several puddled balls into a homogeneous mass under the steam hammer; but never with good results. The difficulty lay apparently in securing a good weld between the surfaces, exposed as they were to the oxidation of the atmosphere. But, if we can credit The Engineer, Mr. Radcliffe, of the Con-, sett Iron Works near Durham, England, has, for a year, been manufacturing, by this process, direct from the puddled ball, into bar, rail, or sheet. In the usual process a charge of about four or five cwt. is used, and each puddled ball, when made, is taken separately to the hammer or squeezer to expel the cinder, and the rough bloom is then passed through rolls producing puddled bars. These are allowed to cool down until wanted for the next process. This consists in cutting a given weight of puddled bars into lengths of from 18 to 36 inches, and making them into a pile, which is placed in a heating furnace and raised to the proper heat, when it is rolled into a bar. This process is repeated—sometimes twice—to produce a superior article. Now, each of these processes absorb fuel, labor, and time, and necessitate waste—waste in oxidation in the heating, as well as waste in the clippings of rough ends. The loss by oxidation cannot be less than five" or six per cent, and the other waste as much, and probably more, at each re-heating. To the cost of the amount of the coal used in converting the pig iron—which is about four times the weight of the iron itself—must be added, at each re-heating, ten cwt. to each tun of iron. These costs do not comprise the extra labor, time, and wear and tear of machinery. If all these are saved by the Radcliffe process, it certainly deserves attention from iron manufacturers, as it does away with all cutting, piling, and re-heating. We copy from TfoeJSngineer the description of the process " The details of the process, as carried out at Consett, may thus be described: Six, eight, or any required number of puddling furnaces are each charged with four cwt. of pig iron. The fettling consists partly of pulverized hematite ore from Ulver-stone, partly of a very rich cinder obtained from the first pile heating furnaces in the rail mill, or from two furnaces specially employed in making cinder from small scrap. The iron is brought to nature as soon as possible, and the blooms are taken out while the iron is yet very young—as soon, iudeed, as the balls will hold together. The moment the iron is ready in a sufficient number of furnaces, the process of manufacture begins. A puddler takes a ball weighing about 80 lbs. to an eight-tun double-acting steam hammer. It is placed on the anvil and struck, first lightly and then, as the mass becomes consolidated, with more force. The cinder is expelled with considerable violence, and we have, at the end of twenty seconds, a flat cake of irjn on the anvil perfectly quiescent. At this moment a second puddled ball is placed on the first. This receives, first a light, and then a couple of heavy blows. The hammer is raised for a few seconds, and then a curious action takes place. The first and second blows apparently expelled most of the cinder, and the mass, seemingly, tolerably solid, lies quietly on the anvil, but in a moment its surface rises like a cake of dough in a baker's oven. The surface seems to boil; littlejets of flame sometimes start from the mass, and cinder pours in a torrent from every pore, flowing over the lump of iron, and running down all round. To what this peculiar action is due we cannot say. That this, in a sense, spontaneous evolution of cinder is a fact we can testify from close personal observation. A few blows from the steam hammer again consolidate the heaving mass. Another ball is placed on it; a few blows; a short pause. The rising of the ma3S and the flow of torrents of cinder follow as quickly as thought—and so the process is continued till eight balls are united. Then steam is brought to bear on the upper side of the hammer piston. The mass of iron is turned and re-turned, while the whole shop resounds with the sound of the hammer delivering blows with the speed of lightning on every portion of the red-hot mass, which finally assumes the form of a homogeneous slab some 3 feet long, 13 or 14 inches wide, and 8 or 9 inches thick. This slab is then taken up by a little steam crane at the side of the hammer, and, while hanging in the air, weighed. It is then run off to a heating fur-naoa, preparatory to being rolled into a finished plate. The heating furnace is of the ordinary kind, and is only used to restore the heat lost by the outer surface of the mass. From the furnace it is taken to the roll mill, passed through the breaking-down grain rolls, and subsequently between a pair of chilled rolls in the same train, and finally it lies on the floor of the shop, a plate with whose appearance the most hypercritical can find no fault. Mr. Kadchffe courts inquiry, and we were afforded the fullest possible opportunities for examining into the process known by his name. We witnessed the formation of many plates, and the following particulars of the manufacture of one, selected almost hap-hazard from our note-book, will show nearly at a glance of what the process is capable: At half-past three P.M. the first of eight puddled balls was brought from the furnace and placed on the anvil. In four minutes and a half this and seven other balls were welded into a slab weighing 644 lbs. At twenty-six minutes to four o'clock this pile was placed in the heating furnace; at nineteen minutes to four o'clock it was taken out and brought to the rolls; at fourteen minutes four o'clock it lay on the floor of the mill ready for shearing. Thus, precisely, sixteen minutes were occupied in producing the plate from the puddled ball. The weight of the plate before shearing was 574 lbs. It was then sheared to the finished size, 30 feet by 3 feet; thickness, 3-16th of an inch, nearly; weight sheared, 448 lbs. Is it necessary to point out here now much is gained in time, coal, iron, labor, and, finally, in money, by the Radcliffe process, as compared with old systems of manufacture ? We think that they will be apparent at a glance to every ironmaster. What we have said in the beginning of this article should suffice to make them clear to others. The question that here obtrudes itself is, what is the quality of the finished plate, bar, or rail ? Unless the answer is satisfactory, the Radcliffe process—ingenious, cheap, and rapid as it is—is comparatively valueless. At Consett we examined some scores of specimens of sheets tested in every possible way. Plates 7-8 inch thick, bent cold to an angle of 90 deg. Thinner plates, bent upon themselves, coiled into a helix, split and bent backwards and forwards, dished up into troughs, twisted and tortured in every imaginable fashion, punched close to the edge —as close as holes would go—yet no symptom of crack or flaw. We have no hesitation in classing the specimens we examined with the very best ship-plates in the market; and yet these plates are produced at a price which has enabled Mr. Radcliffe to take very heavy orders from Dutch shipbuilders, beating Belgium out of the market, and yet leaving a fair profit.
This article was originally published with the title "The Manufacture of Iron—The Radcliffe Process"