THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL. 



17 



THE NEW MODE OF PRODUCING WROUGHT OR MAL- 

 LEABLE IRON DIRECT FROM THE ORE. 

 Patented by Mr. William N. Clay. 



Fig. 1 —LONGITUDINAL SECTION OF BALLING AND PILING 

 FURNACE, WITH RETORTS. 



(ii n0t\ ni'i ai; m ni ini Bfijit|ftii| 



.„//!,,///&„. . . 



The retorts are corered with a Inyer of sand. 



Pie. 2.— PLAN. 



FMrmitt. Hetortt, Chimney, 



Fig. 3 — TRANSVERSE SECTION OF RETORTS AND HORIZONTAL 



FLUES. 



The O are small apertures to allow a 

 portion of the Hame to pass over the top 

 of the retorts. The retorts may be in- 

 creased or diminished, as the waste heat 

 is greater or less. 



REMARKS BY THE PATENTBE, 



Iron is popularly divided into two descriptions, cast and wrought. 



Cast, or pig iron, is principally a combination of tlie metal with 

 carbon, which it absorbs from tlie coke or charcoal of the blast fur- 

 nace. Wrought iron has been hitherto produced by freeing cast iron 

 from the carbon, &c., with which it is combined: the nearer it ap- 

 proaches to a state of purity, the better wrought or malleable iron 

 will it be. 



The richer ores of iron contain the metal combined with oxygen ; 

 if thiit oxygen were separated, the metal would be in its malleable 

 state as wrought iron. 



And yet, the advance of science has left this great branch of our 

 national prosperity so far behind, as to suffer the manufacturer still 

 to continue the practice of impregnating the iron with carbon in the 

 first instance, W'hich carbon must afterwards be separated, by 

 tedious and expensive processes, to produce wrought iron of good 

 quality. 



Bat there are other evils in the common mode. It is necessary 

 for the manufacturer to have a sort of glass floating on the molten 

 iron at the bottom of his furnace, to prevent the oxydation of the 

 recently produced metal by the bl.tst. This glass is formed I'rom the 

 earths with which the ores of iron are mixed, and limestone to fiux 

 those earths : so that, ores of a very superior quality cannot be used 

 by themselves, but only in part, to enrich such poor ores as have 

 more earths combined with them than are necessary for llieir own 

 fusion. Thus it is, that the Hematites, and other rich ores, found 

 abundantly in Lancashire, Cumberland, Cornwall, &c., reach no 

 higher a marketable value at the place of tlieir production than the 

 common earthy ores of the coal districts, although they conl.ain twice 

 as much iron, and that iron of a very superior cpiality. 



Again, English iron is, from its mode of reduction, almost certain 

 to be injured to a greater or less extent by combination wilh sulphur ; 

 the earthy ores, which form nine-tenths of those generally used, are 

 impregnated with that deleterious mineral to a great extent ; the 

 coals from which the coke is formed are likewise more or less sul- 

 phurous; and this gives the high estimation and value to charcoal 

 iron, or such as has been reduced in the several processes by the 

 agency of wood instead of coal. 



It is the object of the patent taken out by Mr. William Clay, to 

 produce wrought iron of best quality, dlTect from the rich ores 



No. 1.— January, 1839.— Vol. II. 



hitherto so little used from the causes beforenamed, by a process 

 simple, rapid, .and economical. 



To make wrought iron of such quality, for instance, aa chain 

 cables are made from, five several operations are necessary, besides 

 the preliminary one of making the coke for the blast furnace, 

 namely — 



1. Roasting the ore. 



2. Smelting in the blast furnace.* 



3. Refining. 



4. Puddling, balling, hammering, and rolling. 



5. Cutting up, piling, ;md rolling. 



All these processes requiring a separate application of heat. 



It is stated in the article on iron, the lOGth number of the " Library 

 of Useful Knowledge," a work written with great clearness, and an 

 intimate knowledge of the subject, that 8 tons 17cwt. 3qrs. 31bs. of 

 coals are required for the production of one ton of finished bar iron ; 

 doubtless, the introduction of the hot blast has reduced the consump- 

 tion of fuel in the smelting operation considerably, and the adoption 

 of anthracite coal may decrease it still further. It seems, however, 

 yet doubtful, whether the best bar iron can be produced from " hot 

 blast pig:" at all events, veiy small proportions of that description 

 arc as yet used in the fabrication of iron of superior quality. 



On the patent plan, the operations are reduced to three ; namely — 



1. Reducing, or preparing the ore in retorts, or other close 

 vessels. 



2. Balling, hammering, and rolling. 



3. Cutting, piling, and rolling. 



The first of these processes is accomplished by the otherwise 

 waste heat of the two latter, so that only two separate applications 

 of heat are required ; and the second operation on this plan com- 

 mences with the iron in as forward a state as the fourth of the old 

 mode, whereby the cost of fuel and labour, and the enormous outlay 

 of capital in land, blast furnaces, and machinery required to bring 

 iron on the old mode to the third stage, are all avoided. 



It is now necessary to state how this is to be accomplished. 



Referring to the plan, it will be seen that between a reverberal ory 

 furnace of tlie common construction employed in "puddling," "ball- 

 ing," or "piling" iron, and the chimney, a range of retorts are 

 placed, which are heated oii their exterior by the otherwise waste 

 heat of the furnace.t 



Into these retorts are thrown 100 parts of Ulverstone, or other rich 

 ore, and 20 parts of coke dust, ground charcoal, .anthracite, or other 

 carbonaceous matter, well mixed together. The retort is closed, and 

 the vapours generated escape as gas. In the course of from thirty to 

 forty-eight hours, as the heat is greater or less, the carbon will carry 

 ofl'the oxygen, and leave the iron in a metallic state. 



It has then to be taken to the balling furnace, where it welds up, 

 like scrap iron, and in fifteen minutes is ready for the hammer ; thence 

 it undergoes the customary process of rolling. 



It is then cut up, piled, and rolled, and the operation terminates 

 with the production of bar iron of superior and extraordinary quality. 



The fourth operation of the old process, " puddling," takes from one 

 and a half to two hours to perform ; the second operation of the pa- 

 tent, only fifteen minutes ; consequently, the consumption of fuel 

 will be mucli less than if refined iron were used. It would be idle 

 to compai'e the simplicity and economy of the first stage of the patent 

 process, with the cost of the three stages required to make the iron- 

 stone into refined iron on the old mode, when we find by referring to 

 page 28 of (he work alluded to, that of the 8.S89 tons of coal consumed 

 in the whole process, 6.989 tons are used up to the refining, so that 

 the 1.9 tons required for the subsequent operations, may be calculated 

 on as more than sufficient for the patent j)lan — to h hicli may be 

 added (if the furnaces themselves do not supply sufficient cinders), 

 the one-fifth part of the weight of the ore used, to mix therewith, as 

 carbonaceous mattey. 



An objection may be made by an iron master that (he mode is not 

 wholesale enough— that (he retorts contain only hundred weights, 

 while his mighty tower furnaces hold tons. If the question were 

 I he production of'pig, or cast iron, there might be some weight in this ; 

 but llie superiority of the patent mode refers more particularly to the 

 production of wrought iron ; and liere, the largest maker in the king- 

 dom must await the laborious and tedious o|)eration of the puddler — 

 him he can only supply with a few hundred pounds of iron every two 

 hours; so that, (lie retorts have only to furnish the same (piantity, to 

 keep up with the puddling furnace of the present system ; if necessary, 

 it might be shown that a balling furnace, on this plan, will produce 

 considerably more than a puddling furnace on the old one^ 



• In this opfi-aliiin, the cxiienses of limestone and breakint; it have also to be 

 incnrreJ. 



+ T.i show what this waste heat is. it is onlv necessary to state, that the chimneys 

 of these fuvnaces iu tlie ii-ou disti-iciii are comjielleil to be liueJ with lire-bricks to 

 the top. 



B 



