The Iron Age 1921-08-25: Vol 108 Iss 8

- fo. 2 ee RAR RAABS a ss ESTABLISHED 1855 VOL. 108: N-. 8 Primitive Iron Smelting in China Tubal Cains of Today—How Natives Make Cast Iron and Put Phos- phorus Into It Without Knowing It UBAL CAIN, according to Biblical tradition, |" was the first ancestor of every worker in brass and iron. It seems a far cry from that le- gendary gentleman and his methods to the modern iron blast furnace, with an output of 500 tons of pig iron per day, and the open-hearth furnace with its correspondingly great yield of steel, but a more surprising thing is that, in the far corners of the earth, methods essentially the same as those primi- tive beginnings are still being practiced. One of the most famous centers of iron smelting by primitive methods is the Ping-ting-chou region of Shansi province, China. How long ago the art of iron smelting was developed there we have no cer- tain knowledge, for iron yields so readily to corro- sion and cast iron is so difficult to engrave and of Mines, Washington isting Engine Used to Raise the Ore Wears a Cheerful very narrow. The small brick structure a T. READ lends itself so readily to being broken up and 1 melted that it does not yield the ancient record that make bronzes so valuable to the student of his tory. The cast iron cooking kettles and other ob jects collected from this region by Berthold Laufe) are quite certainly ascribed to the Han dynasty, but whether the industry in Shansi had its beginning in this dynasty, which was so active in bringing to China the arts and products of distant lands, we do not know. Since iron is mentioned in Chinese records near) 20 centuries before the Christian era, it is not at all improbable that the art was practiced much earlier than 200 B. C., and at any rate we have before us the picture of the metallurgists’ art practiced in es sentially the same way for over 20 centuries. It seems probable that the method used was devised in this region, because it differs markedly from the Expression. The small shafts are shallow and the worl t the right is the shrine of the local deit 451 452 usual method of iron smelting followed by primi- tive peoples. Usually a small rude furnace is con- structed by digging a shallow hole in the earth, such as the Japanese used to use for copper smelt- ing, and through improvements the artisans grad- ually arrive at such furnaces can be found in Szu-chuan and the Philippines today. Those about be described are quite unusual and therefore it is probable that they originated at the place where they are now found. It was my privilege, a few years ago, to traverse as this region on foot, thus affording ample oppor tunity to make observations and secure photo- graphs. F. A. Foster has kindly given permission for the use of some of his own photographs, secured subsequently, that supplement my own. The Chinese have until the introduction of mod- ern civilization exhibited little need for iron; cast iron pans for cooking, chilled cast iron points for Mixed Half Its Weight of Coal Is burned for Packed in three witl davs : ploughs, axles for carts and a few more objects of a simple nature being the principal forms in whicn cast iron was used. To provide saws, axes, knives, razors, etc., for so primitive a civilization, even a smaller quantity of steel was necessary. It so hap- pened that in this region, lying near the center of the ancient civilization of the “Sons of Han,” coa! and iron ore are found in close proximity and thus formed the basis of essential enterprise. The iron ore is not of especially good quality, ac- cording to modern standards, and the deposits are small, seldom being over 3 ft. in thickness. Thev are worked in the most primitive way, one of the illustrations showing how simple is the hoisting equipment and how small the shafts, which are also relatively shallow. The ore, after being brought to the surface, is sorted by hand into several grades ind sold to the smelters. The grading seems to be purely empirical, for I could not learn that any method of ascertaining the iron content was ever practised. THE IRON AGE August 25, 109: 1 At the smelter the ore is mixed with half weight of coal (not coke) and packed into cylin cally formed clay crucibles, 5 in. in diameter a; little less than 4 ft..long. From 250 to 275 of t} crucibles are set upright inside an inclosure 12 6 by 4 ft. Spaces for the entrance of air ben the crucibles are provided by the interstices betw; the loosely laid butts of old crucibles which f: the floor of the inclosure. Over these is sprea layer of coal; the crucibles are set in place, coal between them, until the inclosure is full, w} the front is closed up, the furnace lighted at bottom and allowed to burn by natural draft three days. Then the front is taken down and t crucibles removed, a row at a time. In the meantime, the coal in the crucible robbed the iron ore of its oxygen and reduced to metallic iron. Near the bottom of the crucible the heat has been sufficiently intense so the + After the front is closed it is lighted and is taken out to These then the Crucibles. iron ticles of iron have fused together into an irregular “bloom,” but near the top the iron is in separate particles, from the size of a nut down to fine shot. The native hunters used the finer particles as shot and one evening I dined off a fine roast partridge which had been slain with this very material. Be- ing pure iron it is relatively soft and therefore does not wear away the barrel, as cast iron particles would, and the smooth-bore matchlock which the hunter used was probably not dependent on fine adjustments. The coal which was inside the crucible is not consumed in the process but is partly converted into coke. This is carefully saved and used to mix with clay in making the crucibles. Rigid economy }5 characteristic of all the operations and the tops ©! the crucibles, which usually come through harmed, are carefully saved. Thus the tops of crucibles of one operation become the bottoms the next set. The thick portion at the bottom fu very hard and is used to make the porous bott 7 all 1) ith tho t Le yy) ist 25, 1921 THE IRON AGE tepaired an Necessary That the Used Crucibles Are Is So Cheap and Economy Is in the sun are patched crucibles drying for the furnace, as building materia! in construct- throws the coarser portions back under the feet of ing the sides and also in building house and court ard walls. Even these manifold uses do not absorb all the supply available. These primitive artisans are economical of labor is well as of materials. The clay from which the rucibles are made is spread in the roadway and the ‘fs of the passing pack trains pulverize it, work rganic matter into it and develop its plasticity ingot. The crucible maker screens out the fine clay and work them up into the finished product, at the ex- the passing mules for further pulverizing. The bloom of iron at the bottom of the crucible is worked up into wrought iron objects of every conceivable description. It is heated in a wood fire so that it will not absorb carbon and become hard) and hammered until it is free of slag and earthy matter and gradually becomes welded into a solid These ingots are sold to iron-workers who ey BY “he ~~ ¥ » “SD = i * Melting Down the Cast Iron Has a Blower at the Back to Give a More Intense Heat The crucibles are corrugated to give greater strength : Tilting Furnace {[s a Modern Improvement. A stream of molten unning into the casting ladle The blowing engine is inside the box-line at the right penditure of almost infinite labor. Mostly this is fect. done by heating and hammering but the final finish- ing of thin tools, such as knives and razors, is done by scraping. The tool is finally converted into steel by the cementation process, which seems to be the common practice of all peoples. The finished tool is packed in charcoal and heated until it absorbs enough carbon to be converted into steel of the requisite hardness. Wrought iron made in this way was at one time the sole source of supply of the Chinese artificer of wrought iron and steel, but for many years now scrap steel from foreign countries, especially old horseshoes, have become increasingly popular with the ironworkers as the source of raw materials for their trade. This competition of foreign materials in the principal centers of population has led to the modern decline of the industry, which Von Richt- hofen says was much more extensive at the time of his visit, 40 years ago, than it is now. The small, loose particles of iron in the crucibles are used for making cast iron objects. They must be made to take up carbon so they will melt at a workable temperature and this is done in the fol- lowing ingenious way. The smaller pieces of iron are mixed with coal and put into crucibles about 7 by 14 in. in size, and 70 to 80 of these crucibles are put into a furnace for which the draft is fur- nished by a hand blower. The original material is fairly pure iron but during the melting it takes up It Is a Practice THE IRON AGE iron is structure August 25, | both carbon and _ phosp from the coal. The sm: man adds some impure which they call “hei-tu”’ which probably serves to j duce more phosphorus, ing the melted cast iron fluid, so that it runs well j; molds in casting. These p: tive metallurgists do not k there is phosphorus and bon in their cast iron and quite unaware of the effe these elements on iron and through experience they | worked out an elaborate nology that produces the sired result. In preparing the molds casting, these native artisans display extraordinary ski! The smaller objects are cast very thin and are yet quite pe In some cases wrought iron parts are placed in the molds and the cast iron poured around them, A Fairly Extensive Operation Is the Casting of Sm Objects thus making a composite object, which is better to! some purposes than one made wholly of cast iro: Copper and Brass Research Association The formation of the Copper and Brass Researc! to Dump the Contents of Several Crucibles into One Before Pouring Association, an unincorporated voluntary organization of th copper, brass and copper-alloy interests, has been announced }) its president, R. L. Agass! president Calumet & Hecla Mi ing Co. The purpose of the ass ciation as stated in its by-law: is to stimulate by co-operativ’ effort the use of copper, ras and copper-alloy products. Me! bership is open to producers copper sold here or selling a¢ of copper in the United States to fabricators of copper, and copper products gener the United States and | and to others directly enzas in or connected with the copP' and brass industries. Eligibility for members! the association is determined the Board of Directors, which composed of the following: by ust 25, 1921 THE IRON AGE 455 er Douglas Phelps Dodge Cc. F. Kelley, Anaconda Mining Co.; H, C. Bellinger, oration Co.; Stephen Birch, Copper Co. and Kennecott vration; F. H. Brownell Smelting & Refining Co iz, Calumet & Hecla Min- ( rles Hayden, Utah Cop- Chino Copper Co.; C. V. Consolidated Copper ¢ Consolidated Coppe r Co Calumet & Arizona Min New Cornelia Copper ons Tod, Copper Range Juincy Mining Co.; Robert | t Butte Copper Mining Channing, Miami Cop- red S. Chase, Chase Roll- ind Chase Metal Works 4 tt, Taunton-New Be ¢ Edward H. Bint & Co.; H. J. Rowland & Copper Co., and U. T { T. Hungerford Bras the association are: R. L. Agassiz, Automobile Race for the Steel Treaters Fred S. Chase and C. F. Kelley, vice-presi- Convention Stephen Birch, treasurer; W. S. Eckert, secre ifficers of George Desautels, chairman of the entertainm: ommittee for the convention and exhibition of the American Society for Steel Treating in Indianapolis, Sept. 19 to 24, has issued an announcement of a match race between Frontenac and Duesenberg automobiles. This 50-mile race will be staged on the speedway Wednesday, Sept. 21, at 10.00 a. m. This is the first time in the history of the speedway that the author ties have ever consented to let anyone stage a race of any kind on this track other than the annual race meet on Decoration Day. There will be three or four Frontenac cars and three Duesenberg machines. The manufacturers of these machines are located in Indian apolis and are great rivals. Other races are possible. While the race will probably be the largest event and probably of the greatest interest to the visitors, Chairman Desautels has, nevertheless, arranged for golf and tennis tournaments and ball games between the Eastern and Western delegate Dances, smokers, vaudeville and a continual round of. enjoyment are promised for the visitors. The steel treaters are look- ing forward to having the largest convention and most enjoyable occasion in their h tory. Prospects for technical papers are up to expectations. The hotels \ Small Cast-Iron Cook Stove and the Mold are already reporting heavy reservations for the week yf Sept. 19. William A, Willis has been appointed manager The importing of agricultural implements into Cuba ri¢ ssociation, which has offices at 25 Broadway. is under consideration by Gil & Co.. E. En. C., Con ership in the association now includes the fol- postela, Num. 135, Havana, Cuba, who are importers They desire to deal directly with manufacturers. San Smelting & Refining Co Anaconda Copper uel A. Jenkins, of the company, should be addressed Braden Copper Co., Calumet & Hecla Mining on the subject. \rizona Mining Co m Co., Chino Coppe Metal Works, Chase Rol Copper Range Co., Ea Mining Co., U. T. Huw & Copper Co., C. G Kennecott Copper Co1 ke Copper Co., Michigar Bra Co Miami Coy Lode Coalition Mines C: & Copper Co., Ne Copper Co North i New Cornelia Cop pS Dodge Corporation & Co., Ray Consolidated ; Rome Brass & Copper Mtg. Co., Shattuck Ari- (o., Taunton-New Bed Lo ind Utah Copper Co ir, the Pennsylvania is to have laid 82,500 tons rails, enough for 404 Casting Grate Bars for the Ordinary Clay Stove on Which the Cast-Iron Pans ngle track, Are Set for Cooking ia | Mechanical Control in Foundry Probl Several Cases Discussed Showing How the i Application of Simple Mechanics Produced Results Which Chemistry Alone Did Not Bi] BY J. H. HOPP OUNDRIES generally accept patterns and equip- study the metal content of the castings. An ac { ment with approval or criticism based upon a_ analysis, coupled with a simple knowledge of the a superficial examination rather than a close study. of the various elements, in combination, will gene) bs At times designers are at fault in endeavoring to carry show whether or not the metal mixture is satisfa out certain theories; again, the pattern maker views the product of his art—he would call it—from a stand- point of simplicity of construction or beauty of finish, rather than from the practical utility of the pattern to that joint end of simplifying and foolproofing the molding quality product. To the need of yperation between not 1 1 and indicate only the producing ciose Cco- W e { derab \ foundry superintendent and the pattern department but the engineering department and machine shop superintendent also, certain simple examples have been selected to convey the value of an application of mechanical control of the product. Both mechanical and chemical control are essential; results, whether good or otherwise, are attributed to but one of these factors, which, it hoped, will be clearly shown as erroneou Referring to the accompanying drawing of a ring, one will note at a point diametrically oppos the point of entrance of the metal into the mold on the inside of the ring casting—to space—a basin or well of a size dependent upo size of the casting in question. The temper sand forming this mold, acting upon the fine of molten metal entering it, tends to increase the of cooling to an extent depending upon the am of moisture present, and as a result we have combined carbon. The addition of this basin or well permits iron entering the mold, which cooled rather with a resulting high combined carbon, to flow o the mold proper. In the interval the sand has be heated, and following this a more normal rate « ooling results. As a consequence of this drawing of the original metal poured into the mold, the combin« carbon will be considerably less in the casting itself This practice has been universally adopted and elin nates “hard spots.” The method of controlling the piston ring castings in reality makes the molding operation foolproof against the tendency of using sand too wet or of uneven ram ming or squeezing. The principle underlying the co1 trol can be applied with variations in many wayseand will be found practicable and profitable. With a very desirable mixture, 50 per cent, say, of all the casting conserve rapl produced cannot be machined or at least only at very considerable expense over and above that re quired to machine the other 50 per cent of castings Another example is shown in the molding of plugs The first example is that of individual piston ring astings, commonly used by automobile and tractor In Molding 1 aded Plugs As Indicated, Halt engine builders. Individual piston ring castings, to EES STOPS. Se Sees ener ee $i . Althe h A ! Metal Cat from the Same La meet the exacting requirements of present day machir lh ee nts ing operations, must be soft and particularly free from hard spots. It must be evident that first of all th proportions of the various elements must be suited to + light castings requiring soft metal and having suffi- ‘ient spring to meet the conditions imposed in a gas engine cylil der under heat. I Maki Vic Not in tl Dra but int Assume the conditions are piston ring castings of Manner, and Filling Up the Section of the C extremely light metal section, naturally subject to Original Cuppec Save Weight and to EI rapid cooling, and a complaint of hard spots, resulting aan Sane Cape, he ee ee in too much time required for machining and a high machine shop loss. It is an entirely conservative state for steel barrels, threaded as indicated and p! ment that 98 per cent of the foundrymen of the United with square head for application of wrench. O1 States or Canada would attack that problem first, if dred per cent appear acceptable, but 50 per cen! not for all time to come, from a chemical and metal- repeat, are machinable and 50 per cent are ! lurgical standpoint. sidered to have satisfactory metal for mac! ‘ In a majority of castings, when the chemical pro- though all metal came from the same ladle and throug t portions of the elements are correct, or shop conditions the same gate. preclude the practicability of altering the mixture, it The flask used was a 10 x 24-in. snap type : is possible mechanically to eliminate the difficulties en- match-plate actually contained 60 patterns, f countered, or reduce them at least very materially, as of 15 each, and a single gate with a single mal will be shown. My recommendation would be, first, lengthwise, from which at various points th : ' was conducted to the central rows of patterns 0! 5 iain nee ae er ie aoe a, a side of main runner and by small gates fro! - neer of the C, Kawin Co., Chicago castings to the two outer rows of patterns. 456 ie 3 mek Es \ugust 25, 1921 THE IRON AGE 457 [he importance of the case may be apprehended by seamless kettles satisfactorily, now manufacture ket- vesting a contract’s being involved stipulating the tles up to 1200 gal. capacity. ishing and machining at a fixed price of 250,000 To appreciate fully the complexity of these castings es and yet half of the foundry production proved conceive a kettle of 800 gal. capacity. That means hard to machine. One could stop off the outer rows about 6 ft. diameter by 6 ft. high, with 90 sq. ft. of ids, which are the ones containing hard castings, heating surface. This 90 sq. ft. of surface has 480 stay-bolts connecting it to the heavier outer steam —_——~ — jacket shell. This means 960 points of metal junction F - and that many possibilities of a leak r / re The metal mixture was perfected and then a “guar- / wt antee without limit” was given. I believe it is the only mn guarantee of its kind in connection with pressure ap- ' paratus or, in fact, any kind of machinery. The guar- / e) antee is as follows: “To at any time replace any J e kettle or parts found defective in workmanship or ie material upon return of part claimed defective, trans- a portation charges prepaid.” The pig iron is not judged yy fracture nor charged into the ipola by rule of thumb. Coke and pig iron a1 not bought without certainty of high quality. Another sketch covers the lding of a pulley 6 , } in. in diameter, the rim of whic! nachined on both sides and the face machined to form a double shrouded idler pulley. These castings are machined in an auto- 4% matic machine performing the several operations simul- eA taneously. Should any tool become dulled its replace- kK -2b 1 ment requires complete shutdown of machine ea ee A study of this casting revealed on the drag side es . hvaeon to - ee “ ee a of the rim—and after eliminating h factors as cold \ Molded he Lower Arrang \ d Be TI the Interion 2 wad L + is would be very costly because productio1 NI) | be reduced. One could make new pattern pment with less patterns in a smaller size of flask, proportionately one would not get as many patter e same equivalent area. On an order of 250,000 es the pattern expense could be considered negligi but as all of these are items of cost they must be + - SAAR ! lered. ,o peek | : ] The castings under consideration were in the drag _ the mold, and the molding wasedone in the opposit ( rn nner from that originally planned. The sketc this change together with one other, that of g up the section of the casting which originally ipped out to save weight. This last change being ont necessary to eliminate the hanging sand in the Production as a result was not decreased. ; h casting weighed slightly more than under the fold More Q : + arrangement. Rejections due to hardness irely eliminated. There were, of course, the Redu ejections due to various molding causes. The Metal H veight of metal, however, was an item in the 5) der, but insomuch as the contract was taken at ee 4 e : . p — a _j ry rice, and under the conditions of pattern equip a ae Cdl see... ffered, the foundry had no recourse, whereas a SS liagnosis of the problems at hand before bid = n the work or accepting the contract would tedly have placed the foundryman in a positio1 a price including the additional metal. imple of chemical control that should prov oath ane era | < , ; taint Ss ee Sede yD ng is one of a product mechanically correct C} Enon which fact the manufacturer fought unt mae reed LS The castings failed in service principally Ln , ec. The class of castings is best descri ved as - steam jacketed kettles and evaporating pans, 150 lb. hydrostatic pressure, and in daily us¢ on, 1 vet a sand and unnecessa ard ramming ring, refining, soap making, cooling fluids and that the time of pouring th isting was too great | substances, preparing food specialties, car and the distance that the meta id to travel was too ines, tooth paste, drilling compounds, paints, ong. A casting of 6 in. in diameter having a circum feren f approximately 19 i esulting in the meta ination .the kettle, exterior jacket, stay-bolts having to travel 9% i in each direction from the are cast complete in one piece. The inner gate. ettle is very thin, resulting in quick heating; The sketch will show that a centrally located pour- ng the stay-bolts between inner shell and ing basin was recommended, which permitted filling et outer shell as an integral part of the of the mold much more quickly than before. Of course, esults in unusual strength and reinforcement the total area of the pencil gates—as we term them hin shell. was greater than that of the single gate, but the metal riginal company produced kettles of 175 gal. in no case was required to travel more than one-sixth maximum, but the metal problem was not of the circumference and therefore would not give up 1 the losses were of such moment as to bring its heat as rapidly and as a consequence the combined iptey. The parties who purchased the rights, carbon would be more nearly uniform throughout the ne bankrupt sale, and who have made these casting. In the practice as found, the combined carbon 158 THE IRON AGE August 25, 19 vas from 10 to 20 points higher on the drag side. This formed by contact of the molten iron in the cores, nge in pouring, without any alterations in the metal had to be removed from this mold 960 cu. in. of ire, will eliminate we believe the difficulties caus- It was proved quite conclusively that the practice ne rejectio2 lowed was in reality preventing the escape of a Innumera examples of this general sort of thing tion of this air—and by placing four small rise e give} it the cases cited, it is believed, wil various parts of the cope side of the mold and po ~ e ne cannot afford to pour casting the mold in 12 sec. instead of 8, giving the air a O e other hand, it can also be said that to be liberated, there was produced virtually 101 ngs sl] t be poured too fast. Ih ibstantia ent perfect castings, that is, free from th this, consid <-cylinder automobile isting ausing their rejection prior to this change. pproximately 240 The production in thi It can be stated safely that but a small pri Q { 0 per day for a given nun f all castings finding their way to the scrap h e fitters and assemblers and the scrap ge} produced by pouring too fast, but the illustratio producti The entire mold tioned is convincing of one thing and that is pal l was made of dry sand and it was the cannot carry the speed of pouring to the extrem tent f e manufacturer that he followed good ecure quality any more than we can increase p1 1 fo yract and i doing could se tion indefinitely and still maintain quality. why ild not expect a practically pe} As a further illustration of the principle gov lu f isting’ the rejection of the castings discussed previou \ tated efore, the asting velghed +() A tention is ealled to the gas stove hose connec nch of cast iron weighs approximately % tings shown in another sketch. This shows th« Roughly speaking, th ntents of this mold was 960 proper method of making these and one which The inufacturer’s contentior va that tl ilted in a ecastir 2” too hard to be threaded in ered f 1d fast that the gases did not terior, and it also shows the proper way of pi ave time to form and, therefore, he could not account to assure ease of machining. g pi ts in thi re of these cylinders, My conclusion must be plain. The co-partne iused their rejection. tributing jointly to foundry results are chemist) | p . rrespect I ! ga mple mechani SILICON ADDITIONS TO STEEL 750 kg. square ingots. The ingots. were always | om the bottom. Before the steel was cast, the ai ; ; vas left standing for 10 minutes or so, this meas Effect of Early and Late Introduction on Gas eing necessary especially in the case of cold charg Content and Rolling Discard is otherwise the rolling discard of the steel is increa lue to the presence of the “emulsified” silicic-acid i: | idding icon in the phy steel. Gas samples were then drawn off by a spi perti na t gas content of opel rth ste arrangement. The results show that the gases give ASUlV¢ liscussed by E. Piwowarsky in Stahl ff by the liquid steel, where the silicon is added p fe for June 10, 1920 An abstract of this im maturely, contain a very large proportion of CO, w t een published by Technical Re U, is the most harmful gas as regards the formatior VS. lowholes. Further, when the silicon is added late, \ im ' opinions are held regarding the d hydrogen content falls with decreasing temperatur ! e SMail qual ) and finally ceases, whereas it increases when the s est linary ymmercial ster ) s added too early. ‘ ne the r the view that the silicic acid formed Rolling tests were also carried out to show th ry i I the ferrous oxide 1s retained Dy tn amount of discard resulting (from the presence teel in 1 f of a finely divided emulsified product, occluded gases) when the silicon was added early a iat this weakens the cohesion of the steel, while late. The following table shows the results: of mpairs the weldability of the . tesults of R Che rl 1 ou 1 number of expe mer on ies D nd observations i teel works, with a view to clearing est Material, card aa oe No. C Mn Pp S Ss Ke Ke ls que na etermltr ge wnetner al d how PF , 1dded tT 17 / = ‘ (a) Yerrositlicon dded a sua Lave VO e poss l to enhance the good effects of silicor a . I , : s 0.30 0.69 0.051 0.028 0.18 4 P00 14,00 suppre t leleteriou effects. 4 number of 29 63 0.060 0.036 0.20 27.200 12.800 t ide, and e silicon added (in th 0.37 0.51 0.053 0.044 0.20 34,400 12,100 Ya {TF rent staves o the pouri! 0 , 0.47 0.014 0.037 0.19 9,300 21.740 It was found that when the ferrosilicon was added t (b) Ferrosilicon Added Lat ’ 1 ( ‘ j 0.027 0 O88 ) 3? 00.250 6.800 , the n losses were considerable and the qua! : 0 0.57 0.04 0.0 ( 4 TOC I T ( ne nina! pi \Mauct was mall l 1 j 0.0388 0 "=28 800 4+. 9( y ‘ } : 1 le a e as possiblk ) 0.54 7 0.040 ‘ 6.20 111 ; i ( ® 0 Oe 0040 95 1 o00 A f i eri of eats wa carried out od ey : : \ +, Jt the effect of the gases, incorporated in the steel, The author concludes from his investigations ts qualitic lor this purpose, the melts were made, high temperature favors the separation of the s is far as possible, using the same material and the present in the form of a product of deoxidation ne furnace. The ferromanganese required for de tapping of basic silicized open-hearth heats; and xidizing the bath was added when the charge was com when the ferrosilicon addition is made at as late a leted, and time had been allowed for a state of equi as possible, this reduces the percentage of gas rium to set in between the bath and the slag. The final product, in the liquid, solid and rolled states errosilicon in half the heats was added by placing it 1 . 1e bottom of the ladle at the usual time and in th The American Red Cross is making a drive r half it was added as late as possible by means of _ the smaller industrial companies interested in fir pecial box arranged over the ladle and fitt ed with work. To that end classes are being organized flap-door at the bottom. The quantities of silicon Pittsburgh chapter for the instruction of tho vere so selected as to give a final percentage of 0.20 ployees of companies which do not feel they can » 0.22 per cent in the steel, as it was found that onl) the expense of holding classes in their own plants. vith these percentages was the difference between the company in Allegheny county which wishes to sta nethods of adding the silicon to the bath sufficiently own class, the Red Cross will assist upon applicat marked to be observed. the Pittsburgh chapter. Classes are to be held in) The charges were cast in round chill molds of 540 1003 Chamber of Commerce building, once a wee ‘g. in sets of 34 ingots, except in the case of the heats ginning Sept. 15, at 8 p. m. The fee is $5 per m ntaining over 0.5 per cent carbon, which were cast in’ and the course comprises 10 lessons. " Steel Labor Less than Half Employed Figures of Labor Bureau Show Extent of Falling Off and Trace Curve of Employment—Curves Show Also Unfilled Orders and Pig Iron Produced . WASHINGTON, Aug. 23.—It is estimated that the Upon this basis of estimate, the computation shows ‘ of persons employed in the iron and steel in- the following number of persons employed at the dates in July, 1921, was 283,648 less than at the peak specified as: _— ployment in June, 1918, when 532,798 were en o ad tt January, 1916 ...... 383,308 [he falling off therefore was 53.2 per cent. . a ee 7 : gune, 1918 ..... .. 532,798 econd peak in the number of persons employed in ‘ ; a ‘ ; : March, 1920 .. . 502,133 lustry, by which is meant the blast furnace, stee] = ss : : i ‘ SURE BOE & erds : 249,150 and rolling mill departments, was in March, . with a total of 502,138, so that the decrease in An accompanying table presents the index num f this year was 50.4 per cent. The figures, pre- bers referred to, together with the estimated number of by the Bureau of Statistics, Department of persons employed from January, 1915, to July, 1921 r, are based upon reports showing the number of employed by the United States Steel Corpora . ind reports of the Bureau of Census. “ ports of the Steel Corporation show that the ave1 = afi itn: . . . ° IVY | ry . = umber of persons employed by it in the manufac- | ef he 1 SPHTh properties in 1914 was 131,616. The average mf rie) led er of persons employed in the iron and steel in 2 400t | ffl] 2 in 1914, according to the Bureau of Census, was o oll | 6. Thus the employees of the corporation con : Sf y h | | ~ ~ 00-4 j J 7 A ry gure and Estimated Number of Persons Employed g 200 H4+44 } the Iron and Steel Industry z 100 Base, January, 1916 383,308 | | 1917 1920 { July 130 198,300 Jan 127 {St l Aug. 134 513,633 Feb 129 19 Sept. 133 09,800 Mar. 131 HL 0 Oct 135 517.466 Apr. 130 198.3 5 ) 82 Nov 136 921,299 May 121 £63,8 8 Dec. 136 921,299 June 128 490,¢ t « St h > . July 126 $82,9¢ 0) 1918 Aug. 125 $79.1 Jan, 134 13,633 Sept. 128 190,634 According to these figures the peak of employment Feb 135 l $66 Oct 128 $90,634 2° 1 9 a Mar. 137 25,132 Nov. 124 475 June, 1918, was 39 per cent greater than in January, Apr. 136 921,299 Dec. 113 1 1916, and no month in 1918 showed an excess lowe May 138 528.965 ' , ) June 139 — 532.798 than 34 per cent. In the next high point, March, 1920, 308 July 137 925,132 1921 employment was 31 per cent greater than in January 10.974 Aug. 138 165 Jan 93 rf f 102,47 Sept 137 132 Feb , t 398.640 Oct 138 8 965 Mar &9 14 113,973 Nov. 135 17,466 Apr $1 409 $17,806 Dec 138 28.965 May 79 30 R} $21,639 Jur ‘ 287,48 133,138 1919 July. 6 249 : rw 140,804 Jan. 136 521,299 > -* 140.804 Feb 128 190.634 7 I 1 /\V™Y 148.470 Mar. 125 79,1 Averages tl I 152.303 Apr. 119 $56.1 1915 S6 9, OF a 2 ! May 114 136.971 1916 110 4120,3¢ rt ‘ June 114 136.9 1917 129 496,06 een i 167,636 July 117 = 448,470 1918 137 f , \ 171,469 Aug. 121 163,803 1919 11 14 , $75,302 Sept. 122 167.638 1920 12¢ 482 5 “ ! 175.302 Oct 81 } 79 1921 89 4 ‘ 1S6, 801 Nov 95 { ¥ 194,467 Dec. 113 *Sev © 12.82 per cent of all persons in the industry le prepared by the Bureau gives an index of persons employed in the industry by months seine t Fluctuatior € Steel Mill Em pea ot lary, 1915, to July, 1921. The average for tion and Corporat nfilled Ord numbers for 1915 was 85.83, with the base of tying to January, 1916, when 383,308 persons 1916 In July, 1921, only 65 per ployed in the industry. This period is used as ployed as ; bacause it marked the first complete and satis- 7 reports the Bureau had received regarding em- in all of the industries reporting employment ‘ent as many were em in January, 1916. Portland cement production of the United States in July amounted to 9,568,000 bbl., the heaviest month of ‘ - : = sae the year; 52,036,000 bbl. have been produced to date in Steel Corporation in 1915 had 140,875 persons 1921 and 50,376,000 bbl. Tein ic ac 9 Q9 or Cea re Sg . . - . : . | sing this as 42.82 per cent of all per on: months is about 52 per cent of the corresponding fig in the industry in 1915, then the total number pres for 1990 was 328,993: With this number engaged in neat Saet os ) shipped. Production in seven ) 1 an average index of the number employed A new rate of $1.12 per ton on limestone from Fair- 85.83, then 1 in the index number would be port Harbor on Lake Erie to Youngstown furnaces is to 3,833.08 persons. announced by the Baltimore & Ohio Railroad. 459 an bees ‘ 460 THE IRON AGE NICKEL IN IRON CASTINGS* Alloy Resistance Grids Having Unusual Proper- ties—Effect of the Nickel One of the special uses to which the electric furnace has been put recently is the melting of an alloy of nickel and cast iron for the production of electrical resistance grids. The metal sections of these grids, as shown by the illustration, are quite uniform for each pattern, but there is, among the various pat- terns, a variety of thicknesses. The cross sections vary from % by 3/16 in. to as small as % by % in. The electrical resistance of a perfect casting lies within 10 per cent above or below the fixed listed resistance for each pattern. Good molding is essential to suc- ess in the making of these grids, for with absolutely correct metal a variation of 0.01 in. in width and thickness of section on some of the patterns may mean as much as 12 or 14 per cent variation in resistance. The service for which these castings are intended demands that the metal, even in the smallest castings, e very soft, showing an open, gray, highly graphitic structure in order that they may be resistant to shock, Electrical Resistance Grids and stand up well under rough usage. The metal used for this purpose is a gray iron alloyed with 4 to 5 per cent of nickel, which element, when the composition of the alloy is correct, imparts toughness and pliability to the metal and helps to overcome the tendency of metal to run white and become brittle because of the rapid cooling action of the sand mold. When cold, these castings can be twisted into various shapes, tak ing a permanent set without breaking. The alloy has ipproximately double the electrical resistance of ordi ry cast iro! Following are the specifications and the analyses three heats showing a normal resistance: Specificatio Analy sof Three He Per Cent | Cent Per Cent Per Cent 10 to 2.60 4K 2.48 2.47 Under 0.4 010 0.01 0.018 phot l'nder 0.08 0.055 0.055 0.074 vune Under 0.40 1 0.08 0.10 1 ,60 to 4.01 ) > oO 2 8 \ $00 to 5.06 On account of the nickel content of the metal, whi raises the setting point of the alloy considerably above that for cast iron, causing the alloy to be sluggish at temperature at which cast iron would have great fluidity, it is necessary to cast at much higher ten perature than would be required for cast iron. The temperature of the metal in the ladle, as determined by a Leeds & Northrup optical pyrometer, runs be tween 2800 and 2900 deg. Fahr. (1537 to 1592 deg. C.). The urgency of the situation made necessary tl use, largely, of such materials as happened to be in tock in our works, consequently much of the equip- ent is erude. The furnace is three-phase, combined open-are resistance type, without bottom electrode; is stationary, and of 1000 lb. capacity. The hearth is uilt of magnesite brick and grain magnesite while the roof is made of special fireclay brick. Alternating current is delivered by the power company at 22,000 volts. It is stepped down to 220 volts in three 150-kv.-a. single-phase, Westinghouse, lighting transformers, and *From a paper to be presented at the fall meeting of the American Institute of Mining and Metallurgical Engineers at Wilkes-Barre, Pa., by D. N. Wittman, metallurgist, Westing uise Electric & Mfg. Co., Trafford, Pa. August 25, 192) further reduced to 90 or 110 volts in three autotra formers. These transformers, while not intended electric-furnace use, have stood up remarkably having at times carried an overload of more than per cent for an hour. Four-inch Atcheson grap electrodes are used, and the regulation is by hand. switchboard, located in a convenient place for the { nace operator, contains a voltmeter, three ammet and the power switch. . The required amounts of pig iron, scrap and ni ingot, together with some retort carbon, are char: into the furnace, the power turned on, and the melti done as quickly as possible. The melting down is ca ried on at the higher of the two possible voltages, 110-volt, and the input of current fluctuations fron to 3000 amp. per phase; the melting requires ab 1 hr. to 1 hr. and 10 min. As there is not enough time to allow for chem determinations, the necessary adjustments are mac: from observations of test pieces so shaped as to ir ‘ate the character of the metal as cast in all sect from a feather edge up to % in. Several of these pieces are cast in sand during the adjusting and hx ing period, and additions of silicon and carbon ar made until the fracture of the test piece shows the metal to be normal. As stated before, the temperature, to be high enough to run the smallest grids, should bi from 2800 to 2900 deg. Fahr. in the ladle. The adjust ing and superheating of the metal requires from 30 t {0 min., thus making the time of the heat from 1) to 2 hr. One of the peculiarities of this alloy of cast iro and nickel is a rejection of graphite from the metal when it is just melted, but when the metal is super- heated, it again takes up the carbon thrown out at a lower temperature. It is this property of nickel, throwing out graphite on cooling, which helps to mak« the grids soft and gray in the smaller sections and incidentally keeps the electrical resistance high. The average power consumption, covering a 9-mo. period of operation, was 1100 kw.-hr. per ton, while the electrode consumption for the same period averaged 28 lb. per ton. These figures are rather high, even fo: such a small furnace, but considering that the opera- tion was, in a sense, experimental, and the installation more or less a makeshift, it is probably not as bad as the figures would seem to indicate. With an ideal in- stallation, consisting of a tilting furnace, suitable fur- nace transformers, and automatic regulation, it would be possible to reduce the current consumption by reaso! f having a smoother operation, greatly lessen elec- trode consumption by having less breakage, shorten the time of the heat considerably, reduce the amount labor necessary to operate the furnace, and ther decrease the cost of metal in the ladle. The advantages of this method of melting may stated briefly as follows: There is no picking up of sulphur in the melting process, therefore all of the scrap alloy, such as gates prues, defective grids, and over iron can be charged ack into the furnace and nothing wasted. In fact is quite possible and just as easy to run a heat 100 per cent scrap as it is to run one made up of ron, scrap, and nickel. The possibility of adjusting the metal to the prope! 1position while it is in the furnace. The attaining of the high temperature necessar ast the metal into very small section castings so will run clean, and remain gray and tough. The Fischer Scrap Iron Co., Stevens Point, W has changed its corporate title to F. & G. Auto Pa Co. It will continue to deal in waste metals and ot materials but will specialize in marketing useful parts of passenger vehicles and motor trucks purchased anc scrapped in the last two years in the conduct of ¢! business. Hyman D. Fischer and Joseph Goldstei! the proprietors of the business. Car repair contracts received by the Youngst Steel Car Co., Niles, Ohio, will keep its plant operat ing to capacity into the first quarter of 1922 and afford employment to 350 men. Methods of Preparing Blast Furnace Slag Divided into Four Classes by Carnegie Steel Co. According to the Specific Which Use to are described in a comprehensive way in a book 4 ‘compiled by the Carnegie Steel Co., Pittsburgh, iphasize the properties and commercial uses of book, the ned descriptive matter has been obtained and the naterial. From advance pages of the panying illustrations have been reproduced. here are four general classes of slag mentioned: oled bank slag, fork slag, pancake slag and honey- slag. Study of blast furnace slag has been car- yn for 16 years, and the forthcoming book of some ges discusses, among other thing's, the commercial ‘ concrete and the mixtures used for various pur- , and it incorporates tests to prove the reliability lag and general physical characteristics neces- the construction of buildings, roads and other where the slag may be utilized. make air cooled bank slag the white hot molten run from the slag notch of the furnace into the adles, which hold 200 to 260 cu. ft. or some 7% to ons of slag, and which can carry the slag in liquid as far as eight to ten miles. On the edge of a bank they are dumped and from the Sig le i | slag de Like That Here Shown at the in this method the greater amount of the prin- mmercial slag is produced. the bank the slag gives up its heat to the air revious deposits with which it coalesces to form stone-like substance. Here it weathers from eks to one year or more, dependent upon mag- ntent and demand. During this period of g any free lime is reraoved by natural agencies disintegration of the slag, when in practical eliminated. Meantime, no refuse or waste ma- s dumped on the bank from which slag is to be Yr sale or use. properly seasoned slag is excavated from the lasting or by steam shovel or by both, loaded and hauled to the crusher and the larger pieces ip. It is then passed over a magnetic separator the iron and from thente is elevated by belt to revolving screens where it is graded into al sizes and is ready for the market. slag corresponds in size and general charac- to rough bank slag. It is made at the Colum- ] It Is to ETHODS of preparation of blast furnace slag Lorain 461 Be Put bus steel works of the Carnegie Steel Co., where there is no crusher and where, therefore, earlier methods of disposal are still in use. The slag as it issues molten from the blast furnace is led in long, narrow trenches formed in sand where it is allowed to cool. . When suf- ficiently cool to handle, the long strips or molded pigs of slag are broken up with sledges. The larger pieces are loaded by hand and the smaller by forks into cars to be hauled away to the dump for final disposition after seasoning. Fork slag of necessity carries some sand with it from the trenches and it is offered for mass concrete, road work, etc. Pancake slag is made at the Isabella furnaces of the Carnegie company. The cast on a machine like a pig casting machine into large flat molds about 20 x 45 in. ; deep. The pans of slag travel slag is and 2 in. along an endless chain conveyor and, when Within: a short distance of the dumping point, the coeling Of the slag is accelerated by sprinkling with water. ~ This process cracks the thin sheets of slag and the drop into the car breaks them into small pieces. Much of a concrete aggregate limited this form of slag has been used a in fireproof construction but the production is ipal Commercial Slag, Used for Ballast, Road Construction and Mass Concrete Work, Is Obtained from Banks Plant of the National Tube Co and cost of maintenance of machine high. In quence this method was for a time discontinued as a mode of preparation of slag for regular uses. There has demand recently for a dense blast furnace slag for use as an abrasive, also for the manufacture of ornamental brick. The Isabella furnaces make ferromanganese and the beautiful green slags from them. can be manipulated as pancake slag conse- heavy beeen a for special uses. Honeycomb slag, its name derived from its appear- ance, is the result of numerous experiments to lessen weight without decrease in strength. By the method finally perfected, a slag has been produced that weighs but 30% lb. per cu. ft. and will make up into concrete with a weight as low as 105 lb. per cu. ft., compared with the usual 165 Ib. A large rectangular tank, 40 x 120 ft. and 6 ft. deep, built of brick is located near the furnace. The bottom is cooled, cleaned and dried, and then the molten slag is run from the furnace directly into the tank to a depth of about 6 in. When this layer has cooled suf- ry 4 462 4 % Pancake Slag, Cast on a Machine Like a Pig Casting Machine, Has Been Used as an Abrasive and in Makir Ornamental Brick ficiently, it is sprayed with water, cleaned and dried; of it floats until it becomes cold and saturated wit! then another 6 in. layer is poured, and so on until the water; only the denser particles settle at once to tl tank is filled. It is then broken up, excavated by steam bottom of the tank, shovel, loaded into cars, sent to the crusher and crushed 2. Improved water jet method.—The molten slag and graded to the various commercial sizes. delivered from the furnace through a trough to a Granulated slag is cooled by water immediately on crete pit at the edge of which the trough takes th ts passage from the blast furnace. It is used in the form of a large nozzle fitted with an annular ° manufacture of Universal portland cement, and as a from which water issues in the form of a spray ibstitute for river sand and also as satisfactory filling livered through a 4 in. pipe under 30 to 40 lb. per naterial. Two methods of granulation are at present in. pressure. This causes disintegration and part n usé cooling, which operations are completed by contact 1. The open tank method.—Common granulated slag the water in the pit. By the force of the impact wit! s made by running the molten slag directly into a the water the slag is driven against the opposite side tank or pit partly filled with water by simple contact the pit. Slag thus granulated resembles that mad with which disintegration is accomplished. This prod- the open tank method except that the largest partici ict contains many light, fluffy particles in addition to are much smaller and the entire product is somewh those that are finer and denser. Much of itis as coarse more dense. as popped corn which, when the color is light enough, it Granulated slag is removed from the pits and load rather resembles. Owing to its great porosity much into cars by grab bucket and crane. It will weig! ‘ Slag Tank at the Isabella Furnaces of the Carnegie Steel THE IRON August 25, AGE Co., Where the Jet Method Is Used in Granulating th« ,ugust 25, 1921 Trough at the Concrete Pit Takes the Form of a Issues 1 50 to 60 lb. per cu. ft., dependent upon the kind of smelted, moisture, condition, etc. International Resolutions on Emigration Supervision WASHINGTON, Aug. 22.—The International Emi- Commission, composed of representatives of fteen nations, which has been in se