The Iron Age 1915-11-18: Vol 96 Iss 21

— = 4 ? G Cae New York, November 18, 1915 ESTABLISHED 1855 VOL. 96: No. 2! Ee. ~ > ? > a6 Cc’ € ‘ A Core-Oven Mechanical Draft Installation Some Details of the Combined Forced-Blast and Exhaust Fan Drying Equipment of the Modern Foundry Company, Oakley, Cincinnati A combined forced and induced draft installa- livered into an underground heat supply which tion for its core ovens is in use at the plant of the serves as a plenum chamber from which the gases Modern Foundry Company, Oakley, Cincinnati, reach the three ovens the drying plant It will Ohio. The difficulty of securing throughout the be noted that the scheme admit the drying oven the desired diffusion of the products of com- medium at distributed points in the bottom at the bustion and air mixed with them for the drying of front of each core oven. The idea then is that the the cores by depending alone on either the forced gases will flow backward across each oven. draft or the induced draft led to the combination For the removal of the gases, which have in the é along lines which have proved efficacious in gen- meantime of course taken up considerable quanti — . : © L____ j The Core Ovens Are Equipped with a Forced and an Induced Furnace, as Shown at the Left and the Other Over the Fuel Pit. The Exhaust | nections at Toy d Bottom o ! I Three Ovens Are Shown in the Right-hand lIllustratiorz eral ventilation work. With the opportunity to ties of moisture from the cores, there are three present some of the proportions of the plant, the accompanying illustrations have been prepared and the following account is based on information ob- tained from L. E. Eisensmith, representative in the Cincinnati territory for the American Blower Com- pany, Detroit, which supplied the ventilating, or perhaps better called, gas moving equipment. The accompanying drawings include a plan of the core-oven plant and a section to show the forced blast portion of the equipment and a section to show the induced draft portion. The forced draft fan is located above the furnace of the ovens and the exhauster is located above the pit for the fur- hace fy The forced draft fan delivers partly through the grate of the furnace and partly to the es n chamber of the furnace, and the mix- . e products of combustion and air is de- 1163 Draft Fan, the Former Being Located Over the — ee openings in the floor of the ovens and one near the top of the oven in the back wall. The combined area of the three floor outlets is about 50 per cent greater than the area of a single outlet near the top of the oven. This arrangement has been adopted to secure circulation within the oven and an equable condition as regards temperature and drying capacity at all points, and the use of the ex- haust fan provides for the positive eduction of the gases and vapor, while the positive delivery of the forced draft apparatus is depended on to maintain tan such pressure that there will not be short circuit- ing currents within the ovens. Emphasis is laid on this fact as important, particularly in treating large cores so as not to have parts over-dried while others are still green. The forced blast fan is of the Sirocco type, of 1164 THE IRON AGE November | 3, 19); No. 3 size, operated at a speed of 746 r.p.m., belt A New Type of Skylight Con: nes driven as indicated in one of the reproduced photo- oe ition . — graphs from a 21% hp. electric motor, this size of motor being somewhat greater than ordinarily re- quired for the fan because of the hot cenditions under which the unit has to operate. It is de- signed to supply about one-third of the air for com- bustion, by delivery through the 18 sq. ft. of grate area provided, and the remaining two-thirds over the fire to lower the temperature of the gases, thereby avoiding injury to the cores, while also supplying an atmosphere with maximum opportun- ity for the admission to it of the moisture emanat- ing from the cores. The main heat supply duct, underground as stated, has a cross sectional area about 10 per cent greater than the combined area of the 4 x 12-in. } A oe B eC “Hr _— cr. n Nn ff oe y ry VY uL =) an = aaah a = a O O O y) A wt Tt artless ener Nl ines ea Y Se otion A- RB ry Section C-D Rissdiscecaeeeh ae Air is Forced into the Core Ovens, Part Through the Fuel Bed to Support Combustion and Part Over it to Augment and Cool the Products of Combustion, and the Gases Are Moved by Fans Through Distributed Openings at Opposit« Ends of the Ovens openings through which the gases reach the ovens. Blast gates provide for controlling or regulating the delivery from the fan and there are also blast gates on the exhaust branches from top and bot- tom of each oven. The exhauster is also a Sirocco fan, driven at 520 r.p.m. by a 5-hp. motor. Bristol pyrometers are installed at the rear of each of the three ovens. At this writing figures are not obtainable as to the saving of time in the matter of drying cores, but it is estimated that about 25 per cent represents the result, while a better core is produced, it is claimed, than was the case before the accelerated drying was attempted with mechanical movement of the air. Italian imports of scrap iron and steel for the first six months of this year are officially placed at only 89,615 metric tons against 177,340 tons for the first half of 1914. Pig-iron imports were 96,594 tons against 122,066 tons a year ago for the six months. Imports of steel blooms and ingots, however, were 56,575 tons to July 1, against only 10,997 tons to July 1, 1914. A form of skylight bar construction Waugh glazing construction, employing tected metal and a condensation gutter, ¢ tirely separate from the steel skylight be: Arrang ment of the Various Parts of Construction the Wa developed by the Asbestos Protected Metal Company, Pittsburgh, Pa. It is designed to secure freedom from corrosion and from glass breakage due to deflectior the bar. The skylight beam used is a plain standard section, being a T in the case shown. This bar a is covered ané hermetically sealed by a special coating b. As a pre- liminary the steel is freed from grease, moisture oxides and other surface impurities, after which the steel is heated uniformly and immersed in a bath of a asphalt compound. As an additional protection a cover ing of asbestos felt is pressed into the asphalt while it is soft and hot and this in turn is protected by a coating of special fume and moisture-proof hardening material, the nature of which depends upon the par- ticular service to be rendered. This coating, it is pointed out, is both heat and fire resisting, protects the ste from stray electric currents and galvanic action, and does not take up any great amount of room, being about the same thickness as a 3%-lb. sheet of lead To collect and dispose of the condensation that some times has to be taken care of with a single sheet of glass, special gutters c are fitted snugly over the top of the bars and serve as anchors for the bolts holding the glass in place. This is also made from the con pany’s special metal. The glass construction rests directly upon a cushion d of asphaltic compound. The outside edges of the glass plates and the joints between them are covered and bridged with a half-oval section of asphaltic com- pound e. The cap filler is protected against the elements by a cap f, also of protected metal. The low flat-arch shape, it is emphasized, makes it possible to draw up the cap bolts until the whole cap is under tension with- out breaking the glass, this tension being then utilized to lock the nuts. The cap bolt, nut and washer g is of special shape and is made of non-corrodible metal, such as brass, phosphor bronze or monel metal. Scarcity of steel wire rope is pronounced in Russi, causing great inconvenience to the petroleum producers of the Baku district, according to Consul General John H. Snodgrass of Moscow. Previous to the war wire rope and wire to be made into rope were imported from England, but British wire rope has almost disappeare¢ from the market with the price advanced 300 to 4” per cent. The Southern Foundry Company, Owensboro, Ky. has been awarded a contract by the Excelsior Dri! Vom pany, Springfield, Ohio, for a year’s supply of castings The contract amounts to about 1200 tons. 8, 1915 sn Air Operated Cutting-Off Machine f metal working machinery built wark Foundry & Machine Company, Pa., has been extended to include whines. These are of the air-oper- th one or more heads. The single- e is adjustable to vary the length of from the bar and the multiple ma- the head fixed in position to cut one ig unless the arrangement of the anged. The diameter of the bars ves from 1 to 6 in., the variation in taken care of by changing the bushing stock rests while being cut. ne consists of a power driven head- chuck that grips the end of the bar. nted on the end of a rigid cast-iron ch are one or more air operated cut- The headstock and the reduction sed for driving the bar, the power being an electric motor. Hardened steel the center of the cutting-off heads e bar as it rotates, the bushings being ver than the diameter of the stock being itting-off heads have three air cylinders, ametrically opposite points and one on the he arrangement of these heads being shown rger of the accompanying illustrations. ir cylinder forces a cutting-off tool into the e tools being in line and cutting in the kerf. All three tools on each head are set into the work at once by a common air valve and t away the metal until a breaking section of ap- mately 25 per cent of the original diameter bar is left at the center. This feature is to comply with the specifications for d bars from which shells are made, as the tions contain provision for a fracture test. ressure of between 80 and 90 Ib. is re- ilthough if the size of the cylinders is in- s possible to operate the machines at a pressure. the single-head type of machine a long air er at the end of the bed moves the cutting-off ng the work and various lengths of slugs tained by moving the head for each cut. In of the multiple-head machine it is possible the position of the heads along the bed, but The Machine Arranged to Cut Slugs 19% In. Long from a 5's THE IRON AGE 1165 the air piping has to be changed to with the different lengths of the slug A bar of 0.55 per cent carbon steel, 315 in. in orrespond diameter, has been cut in 35 sec. and a machine with six heads recently cut 2035 slugs 97% in. long from a bar measuring 5 7/16 in. in diameter in 24 hr. Spontaneous Combustion of Land-Stored Coal For the storage of bituminous coal, an open shed with enough superstructure to support the overhead mechanical devices used for handling safer than the closed type, according to George R. Crapo in the Journal of the American Society of Naval Engineers. The overhead conveyor system with the apron 45 to 60 ft. above the floor of the shed is not desirable because of the heat generated by the coal in better and its fall. The heat is smothered by subsequent dis charges from the buckets and a large amount of fine coal dust due to breakage results from the height of the fall. The author is strongly in favor of tempera ture readings to guard against but he does not believe that too much dependence should be placed upon them, as the coal having the highest pontaneous ignition, thermometer reading does not always take fire first A promiscuous use of water in extinguishing fires in a coal pile, it is pointed out, has no great value, as in some cases the temperature of a pile of coal will in crease almost to the coking point and subside, while if the water is used at such a time the coking will take place immediately, thus losing coal that other wise might be saved. -In. Round Bar = 2 IS «> id uh it es Phe ee qt “a ij f ; i : BS | 2 eee : hd : . ey oa i, t ,? : 4 3 ' : nt i fae 7 P Lae ss : : 1 Ae ten an Ree spa, ahaa CREME E! The Process of Case Hardening High Temperatures and Short Cuts to Be Avoided—Influence of Time and Temperature Upon Results—Case and Core Treatment BY R. A. MILLHOLLAND+ There is an axiom that always comes into my mind whenever the subject of case hardening is mentioned, and it is this: The depth of carbon pene- tration in case hardening depends on the time of heating and the temperature at which the work is heated. This is not a new theory in case-hardening practice by any means, for it has been known for a considerable number of years by a very few clever men who did not see fit to talk much about the matter, preferring to keep it as a trade secret. Another good axiom to heed is, high temperatures produce poor results. By high temperatures I mean temperatures above 1700 deg. Fahr. The proper case-hardening range lies between 1600 and 1700 deg. There are an infinite number of reasons why the higher temperatures should be avoided in case hardening. The greatest reasons are: First, the use of temperatures above 1700 deg. Fahr. for case hardening will cause too much carbon to be absorbed in the carbonized area and a supersatu- rated case is the result; second, the high tempera- tures will excessive crystallization of the steel that is being carbonized and serious difficulty will be experienced in refining both the case and the core. Between 1600 and 1700 deg. Fahr. the core structure is not very materially changed by the ordinary heating time, which on a rough aver- age is about 4 hr. Crystallization does take place to a certain extent, but the refined structure is quickly restored by careful treatment. The lower carbonizing temperatures minimize the possibility of the pieces warping during carbonizing. Tem- peratures below 1600 deg. Fahr. are, as a general rule, impractical from the economical standpoint, if for no other reason. The speed of penetration is so much greater at 1600 to 1700 deg. Fahr. that it is impractical to use the lower temperatures where cost is an item to be considered. The depth of penetration varies in a direct ratio with the temperature; that is to say, at 1700 deg. more car- bon penetration will be secured in a given time than will be secured at 1600 deg. Fahr. in the same length of time. The time and temperature factors are very im- portant in case hardening, and to strike a happy medium of temperature and time, is at once both highly desirable and very difficult. A disregard of either factor will result in disaster. On several occasions I have been asked why certain steels seemed to burn out when they had been subjected to long carbonizing heats. Never in all my experi- ence did I find the steel to be the real cause, in almost every case it was due to the use of tem- peratures above 1700 deg. Fahr. Generally coupled with the overheating, the practice of dumping the parts directly from the pots was employed. Both are very poor practice, but the combination of the two is bound to give some mighty poor results. A certain manufacturer was trying to defend the practice of dumping directly from the pots, but he cause *Discussions of the materials and the retorts and furnaces employed in case hardening appeared in Tue IRON AGE, Nov. 4 and 11, 1915, respectively. *Consulting metallurgist dianapolis, Ind Millholland Tool Company, In- admitted that his product gave 100 per cent » service when reheated to refine the core, ang } showed me several test records to that SHORT CUTS TO BE AVOIDED The writer could cite innumerable ents prove the superiority of complete heat treatmen over the short cuts that are so often used to . mize on case-hardening expense. “Safety Firs” signs are conspicuously displayed in almost shop in the country and yet the manufacturer. » some cases, still clings to the before-Noah-and-the. Ark practice of quenching the carbonized pieces directly frem the pot, and calling the case-hardep. ing operation complete. It is always best. whe at all possible, to allow the parts to cool iy pots before they are removed from the carbonizing compound. There is a dual reason for doing t The first is that the carbonizer is saved from oxid tion by the air which would render it almost u less for further service, and the second reason j that on heats longer than 4 hr. the crystalline struc- ture of the core is so coarsened that the hardened part will not have the strength consistent with the factor of safety, upon which principle all conscien- tious manufacturers build their products. However, on heats of less than 4 hr., it is generally the case that the parts can be quenched from the pot and then treated to refine the case, which will give a result that will fill all but the most exacting re quirements. The one objection to this practice applied to this particular method is that the bonizer can only be used once before it loses m strength. The reason is that the air, containing as it does a large per cent of oxygen, oxidizes the carbon in the carbonizer and makes the carbo! useless for further work. If, however, a carbonizer is used, similar to one of those | have already mentioned, a material saving in act carbonizing cost can be effected. On work of a larger nature which requires 4 longer heating time than 4 hr., it is essential t treat both the core and the case. Especially this true of parts that are subjected to shock and vibration. To the uninitiated it is astounding ' see what the actual difference is between a Pp erly and an improperly treated case-hardened par It is safe to put the difference in strength at 4 minimum of 50 per cent for both the tensile streng™ and the resistance to shock. METHODS OF TREATING CASE AND CORE Now let us consider the most practical metho for treating both the case and the core to secu the best results. After the piece has been a bonized the first object is to refine the core. The practice in all cases is the same, whether carbo! or alloy steels are being treated. The only va ation to be considered is the critical temperatu™ of the original steel as received from the mill privt to the carbonizing operation. In the standard mii specification open-hearth, case-hardening stock o critical temperature is very close to 1650 deg. Fahr. and is the one at which the core of the case-har® ened part should be treated. 1166 8, 1915 ré many different methods for doing all only touch briefly on the two most es, For rough work that is to be er after hardening, or for work that light amount of distortion and scale, iting in the open furnace to be the cal method that can be ereployed. A of work can be handled rapidly, ma- ee g the amount of labor per piece. anit, commercial heat-treating furnace can » best advantage. By a pyrometer or levice the temperature of the furnace ilated to 1650 deg. Fahr. and the fur- with the parts to be treated. It is the temperature of the furnace be nearly correctly as possible in order el is not over heated. When the parts saturated with heat and the pyrom- tes that the heat is what it should be, ild be quenched in a heavy oil. From erience and experimenting 1 find for rom the higher heats employed in heat that an oil having a specific gravity of flash point of 420 deg. Fahr. and an nperature of 480 deg. Fahr. is suitable. fications conform to practically all fire egulations, and at the same time the oil ned at considerably less than the many sell for. ther method for treating the core is used n transmission gears and ordnance equip- inywhere that distortion and scaling must minimum. The lead bath is used in d to heat parts. The lead is heated in irnaces designed for that purpose and re immersed in the molten lead and held ntil they are thoroughly heated and then n practically the same manner that the ited pieces are. The advantage of this that the pieces are uniformly heated in t excludes all air and prevents oxidation. s that the parts come from the oil free e and distortion is reduced to a mini- th methods the work should be trans- the furnace to the oil quenching tank s possible to secure the greatest strength i” iil wing the treatment of the core the case e even more careful attention than the rd surface is the primary object of case nd unless the case has the desired hard- tter how much care has been bestowed re the effort is wasted if the case is not igh to fill requirements. The essential ples of treating the case are identical with lved in treating the core. The work is he critical temperature of the case, which rth steel will be about 1400 to 1425 deg. this time it is quenched in fresh,water, treme hardness is desired it is quenched "he lead pot is used extensively where ust be free from scale, but work that sh-ground all over can be very satis- ated in the ordinary furnaces. It is d policy to run test pieces through with that there is some means of checking that are being obtained. The test piece v at least 5 deg. deflection before a com- obtained. The fracture should ‘ore of a moleskin-like texture, and the look like the fracture of a file or that of ened tool steel. e principles of heat treatment apply to is they do for plain carbon steels. The es are that the critical temperatures +m + ture is THE IRON AGE 1167 of alloy steels vary somewhat from those of carbon steels, and it is the general rule that alloy steels will harden quite satisfactorily in a light quench- ing oil. This last feature has a strong tendency to minimize cracking during hardening. In every instance the up-to-date steelmakers can better de- termine what are the best temperatures at which to treat their respective brands, but no matter what the make of steel is, be it carbon or alloy, the prin ciples governing the case-hardening of it are the same the world over. Electric Baking Unit for Explosive Shells To effect a saving in the time required for baking the copal varnish on and to provide unit for doing the inside of high explosive shells a simple, compact and easily operated this, an electric heater i has been de & Pushing Down the Asbestos Cover its the Electric Heater into Operatior ned the ¢ irre t off wher the Paint : Var! sn or the She Ki ‘ ! i he Are rie ved veloped by the Consolidated Car-Heating Company, Al bany, N. Y. The heater unit has a substantial channel-iron base on which the shells are placed. Above is a sheet metal asbestos-lined hood containing the heating elements This is arranged to slide up and down, and when down the heating elements are in the correct position in the shells, the latter being covered by the hood. The heat thus passes directly to the surface to be baked and the hood prevents excessive loss by radiation. The baking can now be done, it is stated, in one to one and one-half hours. A feature is the automatic operation of the control switch which throws the current on when the hood is down over the shells and cuts it off when the hood is raised. This prevents waste of current which would result from careless operators leaving the heat on when no shells are being baked. The heating element is of the type in use for heating electric railroad cars. It alternating or direct current up to 600 volts. operates on Works Accidents That Begin in Play The following bulletin just issued by the safety committee of the Youngstown Sheet & Tube Company, Youngstown, Ohio, deals with a phase of accident pre- vention work which has been brought into unpleasant prominence by happenings at a number of plants: “We have just had one man badly hurt while engaged in a ‘kidding’ match. This is not the first instance of the kind that has happened in our works. Wrestling, scuffing, horse play, kidding and goosing have no place in any working establishment. Things may be started in all innocence and without intent to cause harm, but too often there is some unforeseen happening that re sults in a serious or perhaps fatal accident to one or several employees. Cut out the kidding game.” 2 tore — ne EN—ee-emapsn ARES chick Ra ean care re UTES Sia —— Kt news meget et Uae mwas: ~eeer?* te a ety Peg ige re ato ee ode = ee a ae Panenin cennrnstssting ae oe ee gare te Evolution of the Malleable Proces Early Practice and Poor Iron—How the Elements Jointly Act on Properties of Scientific The process of making malleable iron was slow in entering into a transitory stage, but once started it gained headway and we doubt if any other industry has taken so large a stride in the right direction in the past few years. Very few really know how much more ductile and strong the malleable iron of to-day is than that made twenty-five years ago. Within a quarter of a century pig iron was bought by fracture almost entirely. The blast-furnace man paid little attention to manganese, sulphur and phos- phorus. We know that he was not always right as to silicon, for an iron higher in carbon than another will show more mottles even with the same silicon con- tent; he was dealing with two variables, where he figured on but one. HOW THE MALLEABLE MIXTURE WAS MADE The white iron mixture from which malleable iron was made was arrived at in a very crude way. The method was rule-of-thumb. The initial charge aver- aged 3.5 on the basis of pig-iron grading. The charge for a ten-ton heat was as follows: The sprue and scrap might be considered as eq livalent to No. 6 grade pig iron Then if 10,000 pounds of sprue and scrap were used, 9000 pounds of No. 1 pig iron and 1000 pounds of No. 4 pig iron, the average grade of the heat would be 3.65, which for this case might have been deemed near enough to be satisfactory Some manufacturers did not even use an empirical formula. Some of the iron made at this time stood up as well. But plenty of bad heats were made even when the initial charge was as desired (around 3.5). The iron of this period varied greatly and was not reliable. Chemical analysis was suggested as a means of improvement. The second period dates back about twenty-five or thirty years, chemical laboratories having been intro- duced into a number of plants from 1885 to 1890. Pig iron then could be bought by analysis as well as by grade. The empirical method of figuring charges was eliminated and the practice of obtaining the per- centage of silicon in the initial charge was adopted. IMPORTANCE OF PHOSPHORUS AND SULPHUR Sut even with chemical laboratories, bad malleable iron continued to make itself manifest. The principal difficulty was that the chemist did not know just what elements caused the trouble and those that he did analyze for he considered in the wrong light. Many chemists thought that silicon was the main factor, while carbon was seldom considered. We know now that the silicon content has an important bearing, but that the determination of silicon without knowing the carbon content gives almost useless information. Chemists knew that phosphorus and sulphur were important in determining the quality of steel, so they proceeded to restrict it in malleable. Here again the sulphur content is uninteresting unless we know the manganese, and we are just recently beginning to be- lieve that phosphorus has needlessly alarmed us in malleable iron. The success of the chemical laboratory, as then constituted, was doomed to failure. Poor iron persisted and people concluded chemical analysis was no help; in many plants it was abandoned. But the need for improvement began to be felt more and more, and after several years malleable iron manufacturers began to take up chemical analysis again. Investigation and the BY J. P. PERO AND J. C. Lesson from the Benefits Microscope NULSEN From 1895 to 1900 many malleabk equipped chemical laboratories, doing the some of the problems which confronted continued to look at the analysis in th that of steel, and this more than any vented the discovery of the main difficult ferent elements were considered indeper the effects produced and the possibility of modifying or changing the effect of anoth considered. STEELY IRON One of the most perplexing difficulti: was the occasional appearance of “steel; showed a white, steely fracture after bei and remained so even after having bee: Such iron usually shows a high tensile strengt} is inferior when tested transversely. Its duct almost nil. This iron was obviously unsuited road castings or any subjected to shock. It iron trade. On analysis it was found to be silicon and for a time steely iron was supposed t the result of allowing the silicon to get below a cert limit. Just about the time malleable manufacturers were congratulating themselves on the fact that the of steely iron had been found, some one submitted a sample with silicon 0.94 per cent. All hopes of arriving at the correct solution were shattered. This was not the only trouble. The general practice then was to analyx for carbon, silicon, manganese, sulphur and p! phorus. It was considered that all carbon present the iron after annealing was in the temper graphit form and, therefore, a great many chemists analyz the iron on the basis of total carbon. This was wrong, but it resulted in many perplexing problems. Malleable iron of inferior quality sometimes was obtained, but when analyzed it showed nearly the same chemical contents as that of excellent quality. Th was puzzling and the determination of the cause see! hopeless. ASSOCIATED EFFORT AMONG PRODUCERS This is representative of conditions up to less thar ten years ago, when some of the leading manufacturers of malleable met to talk over the situation. They fe ared that the poor malleable would slowly but surely hurt the industry and prejudice the users, especially ' road men and implement manufacturers, against It was decided that, as no scientific research had ' been attempted, some eminent metallurgist should dertake this work and see if he could not help th Such a man was finally found and wonderful resus have been obtained. We have learned that steely iron can be made Wi the silicon high as well as low, because carbo! was a factor. If the carbon is below certain it will stay in the combined state as pearlite, and steely iron, no matter what the silicon. Uur assumption that too low silicon caused steely 1ror was correct. Iron too low in silicon cannot be tore to give up the combined carbon, no matt wha carbon may be. In like manner we have learned that sulphur manganese are just as closely related. formé was believed that if the sulphur was below ” cent it could not harm malleable, because it @ harm steel. We used to think that an iron wa '™ a: Pamrvnans Aniociation at Atlases tae at per cent sulphur was better than one with 0.00 P can Foundrymen’s Association a tlantic ty, N. J., Sept - : em trong iS 024 23, 191 cent. But if the manganese in these two 1168 8, 1915 ymtaining 0.06 per cent {OSPHORUS LIMITATION some doubt as to whether the limi is to 0.225 per cent was not a need The malleable iron specifications used ot accomplish their purpose; they did 1yer from poor malleable or assure a old specifications contain a clause shall not contain over 0.05 per cent 0.225 per cent phosphorus. Nothing the manganese content and, therefore, phur to 0.05 per cent is in some cases curing bad iron rather than good. Fo vith a manganese of 0.34 per cent would juality with a sulphur content of 0.05 would be satisfactory if the sulphur ent. If a limit is placed on sulphur, ontent also should be limited, but it y be stated that the sulphur content one-third to one-fourth the manganese temptation to unreasonably these elements. no ere 1S as to silicon and carbon. It is mit the percentage of the one without proper corresponding value of the othe greatest improvement from this scier the introduction of microscopi vell as chemical and physical analyses on the state in which the elements exist, is combined with the iron to form ementite whether it is in the carbon, all of which is clearly brought of the microscope. ‘ true been Dor or free HAT THE MICROSCOPE HAS DONE cope reveals whether a piece of malleable aled too short a time or at too low a vhether the annealing temperature was f the cooling was too fast, questions of this research. in many malleable plants to-day is t ypes of test bars from each heat, one set and 14 in. long for transverse test; an round test bars for tensile strength and one set of wedge-shaped bars for The latter bars are 6 in. re % in. thick at the base and taper to This wedge is held upright 5¢-1n. lone and 1 in the point. p hammer delivering a 70-ft.-pound blow lly curled up with each blow. This las direct result of the research work under- ne of the most severe and exacting to cast iron has ever been subjected. All values assigned to them, to which ‘onform before it is passed as 100 per + nave sections are examined under the micro- with the chemical analysis, at once indi- This method of daily control explains now made is so much better in quality ich more uniform than that made fifteen ago—or even five years ago. ago, when we first began to under- ons of the elements in malleable iron the white iron mixture to conform with we thought wedges that stood seven represented good iron. In a_ short of the iron had so far improved that blows, and about a year ago we had o that twenty blows represented 100 ty; but still we are not high enough, ng iron that will easily average thirty- Ss improvement may go is not known, ed bars that stood 108 blows. ner the tensile strength of the iron has average tensile strength of malleable twentv vears f-om 3°.090 + inch. To-day at some plants it acon was juare THE IRON AGE erage O00 f > < 7 r ger Ree are error PORE ne Dar tnaft tested lf per juare 4 LESSON FROM STEEI ASTING MANUFACTURERS i We ay profitably take a k yn from the et 4 é i ( 5 wh ] i Cul I ‘ \ r mos ind ’ : i he supplying castings which, from the . nature of the service req lired of ther ild ve far B more satisfactory if made from a high-grade malleablk | iron. Unfortu ely, however, too many of our mal t eable manufacturers are till satisfied with the pro s duction of inferior iron and are not taking advantage é “ 7 5 } of the knowledge and sults obtained in securing uni 2 formity and high quality This attitude is detrimental to the entire industry and makes it p ible for the f steel casting to replace tne Lieable When malleable ; castings fail in service, it is not the lividual casting ; that is condemned, but malleable iron generally \ { large part of the steel castings used, especially in rail : road work, could be replaced by good malleable, both } from the standpoint of economy and adaptability. ; This may be a strong statement, but it is an i ; controvertible fact that fo rtain classes of wor ; malleable iron is indisputal superior to steel. Cast : ings subjected to shock or to dynamic stresses, if made | of a good quality of malleable iron, will outlast stee | r any other ferrous metal, for malleable iron is not 4 1 S isceptible to fatigue failure as ast steel, owing ; the difference in structure of the two material : 4 ‘ BF} STEEL AND MALLEABLE IRON COMPARED ie 7 Steel is of a crystalline nature, practically int 7 ipted throughout its sectior The | tructuré rh malleable iron is a ystal e, Dut this structure 1 t not continuous, but is interrupted by particles of temps e carbon. Ductile materials such a ist steel and ma : leable iron are weaker under shear than under tensi > and will fail in shear whether the ree applied 3 tension or compressior | When the applied load exceed Line elasth limit the crystals begin to slide over each other he amount ; of such slipping or sliding corresponding to the perma ; nent deformation received. As these crystals slide the infinitesimal irregularities on thei rfaces interlock, ; which increases the friction between these two particu HM ar crystals, bringing them to re and starting th slipping between adjoining crystal! This motion cor - tinues across the section of the metal in question unt i the force applied has become o great that the weake oe crystals part, inter sifying the str ( those remalr , + ing when the next weaker crystals part, and so on unt a complete failure occurs. The surfaces over which these crystal lide are sometimes called slip planes and since the crystalline nature of steel is practically uniform and uninterrupted it is an easy matter for these slip planes to extend themselves across the section of steel in a conti though irregular line, causing cracks and failure. “ena A Nc REL ih thera aeaae s7 «: a [ AS Malleable iron starts to fail in the ime mat but before more than one or two adjacent « ry tals have failed, the incipient fracture will have run into a ten per carbon spot. These spots usually are located at the conjunction of three or four crystals, so that there : are three or four paths along which the fracture may continue and the probability 1 } the one seriou rack will break ip, taking three or four of thes bs paths. These new paths, in turn, I nto cal ) pot whether the up. In this way regardless of further broken large serious fra straight across eture FAILURE DUE TO . eee ene ee ae a nen peng ee It is hoped that we soon may learn more about ~ fatigue failure and establish why malleable iron is les susceptible to this thar teel. Malleable iron has a : further and very important advantage over steel in the oundness and solidity of its sections, provided care i ee taken to eliminate shrinkage spots. It is cast at a tae lower temperature than steel and hence is free from ie occluded gases which cause blowholes and unsoundne 1170 Soundness of section, coupled with the fact that the ratio of ultimate strength to the so-called elastic limit of malleable is much higher than the same ratio in steel, should justify a much lower factor of safety in design than would be permissible in cast steel, as the allowable working stress of malleable iron is about 10 per cent higher than that of steel. As an illustration we will assume that the ultimate strength of cast steel is 65,000 lb. per square inch and the elastic limit is quoted at 35,000 lb. per square inch. Many malleable plants to-day are producing iron with an average ultimate strength of 50,000 lb. per square inch, which, while lower than the ultimate strength of steel at 65,000 lb., still has an elastic limit of approxi- mately 38,000 lb. per square inch or about 8 per cent higher than that of steel. Since in the design of cast- ings it is the elastic limit and not the ultimate strength which is considered, it would seem that the facts, in connection with the superior soundness and freedom from blowholes of malleable castings, should be ample justification for using a lower factor of safety in arriving at the working stress to be used. Malleable iron has greater rust-resisting properties than any of the other ferrous metals. Therefore, for use in railroad, implement and other work subjected to corrosion, it is to be preferred to cast steel or gray iron. Our desire is to see a much-abused metal (chiefly so through the ignorance, or carelessness bordering upon dishonesty of too many of the producers of mal- leable iron) given its rightful position in the engineer- ing world. An earnest hope is expressed that this paper may awaken an interest in producers of mal- leable iron castings which will tend to secure the high- est possible quality in one of the most useful of the ferrous metals. AMERICAN DIESEL ENGINES Summary of the Different Types at Present Built in This Country The following engines of the Diesel type are built at present in the United States, according to statistics presented by Max Rotter, chief engineer of the Busch-Sulzer Brothers-Diesel Engine Com- pany, St. Louis, in a paper read at the recent Inter- national Engineering Congress at San Francisco. Although representative of the general develop- ment of this type of engine, in this country, several more or less known makes are not mentioned. Snow oil engine, built by the Snow Steam Pump Works, Buffalo, N. Y. This engine is of the build- er’s own design, based upon its experience in the manufacture of large gas engines. The air com- pressor and scavenging pump are mounted on the side of the frame, and driven by a drag-crank on the end of the crankshaft. The regulation is ac- complished by varying the stroke of the fuel pump plunger, by means of a sliding wedge, operated by the governor. This engine employs a modified type of open nozzle. Allis-Chalmers oil engine, built by Allis-Chal- mers Mfg. Company, Milwaukee, Wis. This en- gine is designed under the Lietzenmayer patents, using the open type of fuel nozzle of that name. The air-compressor is mounted on the side of the frame, and actuated from the crankshaft. The regulation is performed by varying the effective stroke of the fuel pump plunger, under governor control. A gravity oiling system, with filtering arrangements and pump, is used for all important bearings; the lubrication of the cylinders, and in special cases that of the exhaust valve stems also, is performed by a force-feed oil pump. Four-cylinder, vertical, four-stroke-cycle Diesel- type oil engine built by McIntosh & Seymour Cor- poration, Auburn, N. Y. These engines are built in accordance with the designs of and under the sole THE IRON AGE Novem! rights to the U. S. patents of | Sw Diesel Engine Company, Stockholm, S\ n. use the Hesselmann patent fuel atomi/er. j; junction with the by-pass type of fuel regylas: under license from Busch-Sulzer Bros.-{)jcce) p,. gine Company. The air compressor { oda iature A frame unit, directly coupled t the crankshaft, and conforming in its genera) a. pearance with the working cylinders and the frames. The arrangement of air tank unig and has the object that the tanks may be manir lated from the engine platform, instead of. usual, from the floor. Fulton-Tosi oil engine, built by Fulton [po Works, St. Louis, Mo., under license from Frane Tosi, of Milan, Italy. The engine is of the 4 frame type, and employs the variable pump barra volume type of fuel regulation, with governor ¢op. trolled diaphragm. Dow-Willans Diesel type oil engine, built py Dow Pump & Diesel Engine Company, Alameda, Cal., under license from Willans & Robingsop, Rugby, England. This engine is of the A frame type, with a Reavell air compressor directly coupled to the end of its crankshaft. Fulton Diesel-type oil engine, built by Fultoy Mfg. Company, Erie, Pa. It is of the marine crankcase style, with a directly driven air-con. pressor, mounted upon the crankcase, symmetri- cally with the working cylinders. This company confines itself, the present time, to units of 100 hp. and under, of the full Diesel principle. The Harris valveless engine, built by South- wark Foundry & Machine Company, Philadelphia, Pa., under the Harris patents. The engine is of the vertical, two-stroke cycle type, with stepped pistons performing the double function of scavenging pumps and low pressure stages of the air com- pressor, the intermediate and high pressure stages of which latter are arranged in line with the work- ing cylinders. The Diesel engine, built by Busch-Sulzer Bros.- Diesel Engine Company, St. Louis, Mo. This com- pany is the continuation of the original Diesel Motor Company of America, in combination with Sulzer Brothers, Winterthur, Switzerland, and the late Dr. Diesel. The engine is of the four-cylinder, vertical, four-stroke cycle, enclosed crankcase type; with the air compressor directly driven from the crankshaft, and mounted on the crankcase sym- metrically with the working cylinders. The en gines are provided with positive pressure lubrica- tion, the filter and cooler for which are placed in an accessible pit formed at the end of the founda tion. The engine is provided with cam-operatec compression relief, automatic compressor pressure regulation, automatic injection regulation, and p's ton cooling. Cambria Loses Jones Mixer Case The United States Supreme Court, by its refusa! * grant a writ of certiorari Nov. 8, decided finally that Cambria Iron Company must pay the Carnegie >‘ Company $568,305.93, with interest, from May 1, “ for the infringement of the Jones mixer patent use? © making steel. This amount was allowed by the Thiré United States Circuit Court of Appeals. It was co™ plained by the Carnegie Company that the defendant company had infringed on the Jones patent from Nov. * 1895, to Oct. 31, 1898. During this period the defen¢™ company passed 520,188 tons of molten blast-furnace metal through the mixer and remelted in cupolas ® - the same quantity of blast-furnace iron. The Carnes® Company averred that there was a saving of over *” oe ton by the Cambria Company through the use 0 ™ Jones patent. NEW HEAT-TREATING FURNACES Steel and Cyanide and Lead Hard- High-»} Outfits with Preheating Ovens ew types of furnaces for high-speed rk and for cyanide and lead hardening, save labor and fuel and to produce ency in heat-treating work have been by the Bellevue Furnace Company, these is a gas furnace for high-speed a preheating oven, the exhaust heat from high-speed steel oven being utlized for warming preheating chamber. The preheating oven is ve the high-speed one, the exhaust heat atter being carried to the former by two la itlets connecting the two chambers. The irne! located in grooves in the lining at the _eceonsinciie apa ccasiictiilimaieadiiansiiiannia Heated Furnace for High-Speed Steels with a Preheating Oven Which Is the Exhaust Heat from the Main Oven ne hearth, so that the flame does not come with the work. There is one inlet for r which is used at low pressure. To get results high-speed steel is usually pre- ‘ted, and in some shops where a furnace is not or this work the hardener will take his he opening of the high-speed chamber, will heat it to a cherry-red color and then the high-heat chamber. This method nsiderable time and it is claimed does give good results. With a furnace of nown the hardener can place his steel in chamber, where it is heated by the at from the lower chamber and the final n the high-speed chamber can be done ng of time. With this furnace a num- es can be treated at a time. The high- ee ace chamber is 9 in. wide, 12 in. deep and i chamber 11 in. wide and 18 in. deep. THE IRON but the furnace is furnished in a larger Vertical High-Speed Steel Furnace Having Py rometer Holes to Enable the Heat in Any to be Determined This furnace is designed particularly for harden- ing gears, milling cutters and other tools. It is stated that the high-speed chamber will heat up to 2250 deg. Fahr. in 15 or 20 min. The vertical high-speed steel furnace shown, several of which were recently built for the Ford Motor Company, is another type that has been de- veloped. This furnace is 36 in. deep and 7 in. in diameter. The preheating oven which is heated by the exhaust heat from the high-speed oven is 36 in. deep, 10 in. wide and 11 in. high. The verti- cal furnace is provided with three pyrometer holes so that a test for uniformity of heat can be made in any part of the furnace. It is stated that when the high-heat oven is at 2200 deg. Fahr. the tem perature of the preheater is 1450 deg. A combination gas or oil furnace for general tool work and cyanide and lead-hardening furnaces is also illustrated. The tool furnace is heated by the exhaust heat from either the lead or the cyanide pot or both. The heat passages from the lead and cyanide furnaces to the tool furnace are 5 in. in diameter, inside measure, and are clay lined. Out- lets are provided so that when both the cyanide and the lead furnaces are in operation and the heat Cyanide Furnace Using Gas or Oll as Fuel and Equipped with a Preheating Oven Heated by the Exhaust from the Furnace Proper we Bi SR een megen ic 8 eae eat panes Senta ra 4 5. starr ny agate Ta th Nt Aer Or ee aes os 7 es ee ~ wo nuntintitiirmantieeapite~cigpiniainal | ea ter ememeatepepeniadns teeny iat least trealiaete antisisstndailn. SAG ae rene Se —_— 4 vi ee ‘ 1172 THE IRON AGE Novembe 18, 191; from only one of these is required to heat the tool Drinking Water for the Fa a furnace, the exhaust heat from either the cyanide Experience has indicated that water " or the lead furnace can be discharged outside by Se ee ee eer palatable should not vary more than deg., according to R. F. Massa, in a cont) American Water Works Association. A d supply for any large number of people encourage the use of a sufficient quantity son. To this end it s} attractive by being ke; the lips of the consu clear and sparkling, tainable at attracti conveniently placed, a: closing a damper and removing a cover to an open- ing in the pipe, allowing the escape of the heat at the back of the furnace. The tool furnace has an independent fuel connection and burners, as the il- regulated to the rig tempers ture. t An average person « bout 3% pints of water per day, the rats of consumption being increased heat and exercise. Bubbling f tains are more economical thay cups. A properly designed bubbler will furnish the water in the form of a jet of such a hei most of it can conveniently | drunk without allowing the lips t come in contact with the orifice It does not pay to cut down the size of the stream in order rht that ‘ a e flow, time is wasted. Cleanliness and the appearance of cleanliness are essentials. In general, mechanical cooling seems to be more economical than ice cooling, although it is difficult to obtain exact comparisons. What- ever the system, it should be abso- lutely clean. Surfaces in contact with the water should be smooth A Combination Oil or Gas Furnace for General Tool Work and Cyanide and Lead Hardening Furnaces, the Exhaust Heat from the Latter Pair Being Utilized to and accessible for cleaning; Cons Heat the First should be designed with that in view. lustration shows, so that it can be operated inde- Only a limited area can be satisfactorily served pendently of the other two furnaces. The lead pot from a single refrigerating unit, for the heat losses is 16 in. in diameter and 16 in. deep, the cyanide #7¢ 80 great as to demand too low a temperature for . ; . . safety near the,cooler in order to get palatable water pot is 10 in. in diameter and 10 in. deep and the at the end. The nember af Seats eee heating chamber of the tool furnace is 11 i