The Iron Age 1934-07-05: Vol 134 Iss 1

THE IRON July 1934 Editor Managing Editor Consulting Editor News Editor Machinery Editor Pittsburgh Detroit Boston Cleveland Chicago Editor Washington Cincinnati Contents Chaos Misses Its Train Rapid Testing Metallic Coatings Molding 30-In. Cast Sheaves WE DO OUR PART Wet and Dry Processes Enameling Effect Heat Treatment Die Steel Selecting Machine Graphical Balance Applied Furnace Operations Meeting Open-Hearth Technicians American Society for Testing Materials Convention New Equipment News Washington News Automotive Industry June Pig Iron Production Markets Personals and Obituaries Construction and Equipment Buying Products Advertised Index Advertisers THE IRON AGE PUBLISHING COMPANY FRANK, President GRIFFITHS, Secretary BAUR, General Advertising Manager PUBLICATION OFFICE: Corner Chestnut and Sts., Philadelphia, Pa. EXECUTIVE OFFICES: 239 West 39th New York, Y., ADVERTISING STAFF Member, Audit Bureau Circulations, Emerson Findley, 311 Union Bldg., Cleveland Member, Associated Business Papers Herman, 675 Delaware Ave., Buffalo, Hottenstein, 802 Otis Chicago Published every Thursday. Subscription Price: Peirce Lewis, 7310 Woodward Ave., Detroit United States and Possessions, Mexico, Cuba, Charles Lundberg, Chilton Chestnut $6.00; Canada, $8.50, including duty; Foreign 56th Sts., Philadelphia, Pa. $12.00 year. Single Copy Cents Ober, 239 39th St., New York W. B. Robinson, 428 Park Bldg., Pittsburgh Cable Address, ‘‘Ironage, N. Y."’ W. C. Sweetser, 239 West 39th St., New York D. C. Warren, P. O. Box 81, Hartford, Conn. EIGHTIETH YEAR SERVICE THE METAL WORKING INDUSTRY & f | ¥ 1 8 4 THE IRON AGE.......... JULY 1934 e | THE IRON AGE ... JULY 1934 ESTABLISHED 1855 Vol. 134, No. Chaos Misses Its Train machine age has defeated us, the price sys- tem doomed and are faced with the threat national bankruptcy and perhaps general chaos within months.” From the article, Technocracy?” the New Outlook, November, 1932. HIS was the cheerful message delivered America just months ago. Chaos now two months overdue, according this prophecy. And does not appear that there any likelihood its arriving even later train. Instead plunging headlong into the abyss, predicted, manufacturing activity the United States April, 1934, the scheduled arrival date chaos, was just per cent greater than was November, Other countries “suffering” from the “price sys- tem” have shown equally disappointing results far the prophets gloom are concerned. the first quarter 1934, industrial production Great Britain averaged 13.3 per cent above its level November, 1932; Canada, March this year, showed per cent increase; Sweden, the current February, per cent gain, and France, per cent, this February, all compared with November, 1932. country any industrial importance failed show gain. More recent gloomy predictions have shown equal reluctance make good for their sponsors. was not long ago that American business suf- fered from cold chills and cold feet through the threat general automobile strike. More re- cently the threatened business depressant was the non-materializing general steel strike. Most the things that keep awake nights worrying never happen. There are many who will regard the current sud- den drop steel production signal for busi- ness caution. They will see indicator recovery collapse, instead encouraging proof that producers and consumers alike recognize the passing the strike threat and the beginning the end the closed shop labor lobby. Like the old ladies who see tures that they may have their blood curdled, many business men will pay good money for sup- posedly “confidential” services that profess give them privileged peep holes the veiled economic and political future order that they may plan their business actions. Unfortunately, good news not nearly salable bad; hence the con- sistent but changing procession terrifying and largely imaginary bogies which are paraded past these peep holes. about time that American business men held experience meeting and found out what has cost them act upon pessimistic forecasts. The inveterate optimist may not safe guide fol- low, but his accuracy record for the next few years will far ahead that the prophets gloom. Rapid Testing the Characteristics accurate determination the ultimate thickness and the quality metallic coatings most timely requirement the entire plating industry. Therefore careful scrutiny should given this article internationally known authority electro-metal- lurgy, which presents unique method easily finding the thick- ness outer pure metallic coating, and, addition, shows how the thickness and quality the intermediate layers binary alloys can estimated with pre- cision. The c..< zinc-coated iron wire treated detail and the same practices can used for tin, cadmium, copper, nickel, and various other pure metal coat- ings. The author discusses only the case coated wires, but simple manipulation the de- veloped formula extends its useful- ness flat surfaces. Only min. are required for each test, and the procedure practically automatic, thereby making use- ful routine laboratory test for product control. thickness and other characteristics metallic coatings many ways rather difficult technical prob- lem. Thus, chemical analysis the amount metal used surface pro- tection various metallic products, only indicative the total percentage the metal chemical element. Due alloying effects the coating upon the underlying metal, the actual thickness the coating depends also upon various metallographic reactions between both phases which, turn, are functions the applied methods plating. majority instances the thick- ness intermediate zones alloys increases with the temperatures util- ized plating. Accordingly, coat- ings produced the immersion various parts molten metals are characterized heavier layers alloys (as gradation zones) com- parison with those electro-plated surface layers. The existence in- termediate layers mostly binary alloys, however, has very marked influence upon the quality the coat- ing because the well known dif- ferent properties alloys com- pared with those the respective components. Many metal plating processes produce hard and brittle alloys the intermediate zones which cause cracking the coating when- ever the plated stock subject mechanical deformation. The spall- accurate determination the 12—The Iron Age, July 1934 ing and surface layers frequently observed and may traced the brittle alloys such binary systems Fe-Sn, Fe-Zn, Cu-Cd, outlined before, even reliable chemical analysis metallic coat- ing fails give the desired informa- tion. Perhaps the most generally used procedure studying the prop- erties surface layers consists far judiciously conducted micro- scopic examination cross-sectional specimens plated articles. Although possible measure the thickness various layers with considerable accuracy, this method requires ex- pensive laboratory facilities, experi- enced personnel, and quite time consuming. specific care not exercised the preparation the samples for tion, the coating easily “smeared” polishng the coating metal reacts with some ingredient the low melt- ing alloy used for mounting the speci- men. Almost needless state, these and similar factors may con- siderable extent affect the accuracy any experimental deductions. addition the methods described above probably the most common pro- cedure testing galvanized articles, especially galvanized wire, was that Preece, wherby the thickness the entire coating estimated from the time required for complete solu- tion the coating neutral con- centrated solution copper sulphate. laboratory routine the number “dippings” definite duration (ordi- narily min.), required completely dissolve the coating bare wire, serves index the time factor the Preece test. The simplicity this method perhaps the only ex- planation for its practical utilization the present time. Modifications the Preece test consist dissolving the zinc coating acids and cal- culating the volume weight the coating from the difference weight measuring the volume the liberated hydrogen. Several the above alternatives were advocated Auperle’, Bauer’, and Other investigators, such ordinated the thickness metallic coatings with velocities solution. Vondracek’ and his collaborators the Technical University Brno, Czechoslovakia, have determined the thickness zinc coatings more ac- curately dissolving the surface metal sulfuric acid and measuring the volume hydrogen which results. The principle this method bases the fact that sulfuric acid readily dis- solves zinc and zinc alloys whereas low carbon iron practically not at- tacked. the chemical equivalents and are numerically very close, possible calculate the thickness zinc coating the length and original diameter the tested wire are known. However, difficult, not impossible, cor- relate the qualitative characteristics the pure surface layer and the underlying gradation alloy zone. This latter relationship seems about the most important index the quality galvanized wire galvanized products general. Bearing mind the many short- comings the numerous contempo- rary methods, the development rapid, cheap, and reliable process for the determination metallographic properties all metallic coatings seemed warrant exhaustive search for such more less uni- versal procedure. After considerable experimentation, the author has con- ceived electrolytical method which | P : : vire, tions ving cal- the the tives such tallic ition. ators Brno, the ac- rface uring sults. dis- ereas at- alents very the the the cor- ristics and alloy seems index short- for raphic uni- which Metallic Coatings appears fulfill all the above require- ments quite satisfactory manner. Experimental Procedure This determination the charac- teristics metallic coatings based electrolysis. Therefore the electro- lyte must concentrated, slightly acidified solution simple salt (sulphate, chloride, etc.) the metal which has been used coating the wire. The specimen selected for the test submerged vertically into the solution. order make the test accurate possible exactly measured length the sample ex- posed covering both ends the wire with paraffin, wax similar material. The length the wire ex- posed electrolytical action thus accurately determined. The length the exposed wire not specified, but (1.25 1.625 in.) are ample for reliable determination. The sample connected the posi- tive end storage battery, electric volts. cylindrical cathode sur- rounds the wire sample. The moment closing the circuit recorded stop watch and volt well am- pere readings are taken frequent intervals. During the original ex- periments both were read every sec., but was soon discovered that automatically registering voltmeters and amperemeters are satisfactory and far more convenient. Inasmuch the electrolyte concentrated solution salt the respective metal, changes its concentration composition will noted during the Therefore the electric resistance re- mains practically constant during that part the test. evident that during the anodic solution the pure metallic coating both voltage and am- perage also remain constant and their respective values will shown horizontal straight line when dia- gramatically recorded. After the pure metal the coating goes into solution the intermediate layer gradation alloys the coating are exposed for electrolytical action. The anodic potential will change (ordin- arily increase), and the current in- tensity will decrease. The first devia- tion from horizontal straight line the time-voltage diagram therefore indicates that the surface layer the pure metal has disappeared and the intermediate zone been reached. During the anodic solution the intermediate alloys the coat- ing metal the voltage will constantly deviate from its previous momentu- ous value (being ordinarily in- creasing magnitude). curve thus recorded for this part the diagram. Upon disappearance the gradation DR. ALEXANDER GLAZUNOV Professor Theoretical Metallurgy Pribram, Czechoslovakia alloys the dissolving action the electrolyte, the original metal ex- posed the solution and new direc- tion the curve, i.e., another horizon- tal line, marks the instant when the entire coating has been removed. This indication also marks the end the necessary readings. The exact thickness the metallic coating may then calculated from the electro-chemical equivalent, the specific gravity, and the diameter thickness the tested wire. The mathematical relationship for the measured values reads follows: exAxt a= where surface layer (in cm.). e—Electrochemical equivalent. amperes. seconds. gravity gm./cm*. the wire (in cm.). the wire (in sents the wire surface exposed. flat surface the area exposed could substituted. The gradation zone between the surface layer and the original metal perage for both alloying elements. accurate mean coefficient for the gradation alloys may determined from the quantitative ratios the Voltage Time minutes oO Intensity, amperes Fig. 1.— Variation the 0.24 voltage and amperage dur- ing de- termination coating thickness iron wire. The initial straight lines the left indicate pure zinc only, the curved portions indicate alloys zinc and iron, straight right portions indi- cate action pure iron wire. Table Readings ob- tained during the determina- tion the thickness and character zinc coating iron wire. The wire diameter equals 0.0788 in. and the coating plated electrically. Data are from curves Fig. Table Seconds Voltage Amperage Remarks 6.2 0.23 Current Pure zinc lay- zinc being dis- 6.2 0.23 6.25 0.23 150 mediate layer 0.20 165 170 7.75 0.20 175 7.8 0.20 wire ex- 205 7.8 0.20 240 7.8 0.20 coating metals 270 7.8 0.20 dissolved. 300 7.8 0.20 330 0.20 360 0.20 The Iron Age, July 1934—13 Amperes Table Seconds Voltage Amperage Remarks 0.27 8.0 0.25 mediate layer 8.25 0.24 8.4 0.22 105 8.75 0.22 115 8.8 0.22 wire ex- 120 8.8 0.22 posed; all 150 8.8 0.22 coating metals 180 8.8 0.22 dissolved. Table obtained zinc coated iron wire. Diameter wire equals 0.074 in., and the zinc coated thermally the use liquid zinc bath. Note that even the extreme outer zinc layer alloyed with iron. binary systems, like Fe-Zn for gal- vanized wires, etc. The total both percentages the corresponding metals obviously 100 per cent and, therefore, only one the phases needs mathematical consideration. brief deliberation may assist-in clarifying the following deductions. During the first seconds the electrolytical ac- tion upon the gradation zone, the alloy will naturally rich the coating metal the case galvanized stock), the concentration which metal will gradually decrease until becomes per cent, while the iron the original phase reaches prac- tically 100 per cent. For galvanized wires the average current intensity the transition alloys equal 0.67 times the original intensity amperes. Testing Technique The apparatus required for prac- tical determinations coating thick- ness and characteristics includes suitable container for the electrolyte, trode, cathode, stirring mechan- ism for the electrolyte, registering voltmeter, and registering ampere- meter. With this equipment and following the process summarized the foregoing paragraph, the test requires some min. for its completion. The original work was carried out using soft iron wires coated various thermal and electrical proc- esses with metallic zinc. The elec- trolyte was slightly acidified solu- tion zinc sulphate. From the many series complete tests with wires galvanized under varying conditions, two examples should amply illustrate the details well the practicality this new method. 14—The Iron Age, July 1934 Table the values from de- termination the characteristics electrolytically coated wire are presented. These values are taken from the curve shown Fig. Table illustrates similar values for thermally zine coated wire. comparison both series shows the distinct absence pure zinc surface layer the thermally coated sample. This may explained the higher rate thermo-diffusion zine the increased temperature the liquid zine bath used the coat- ing process. The same reason ac- counts for the much heavier inter- mediate zone thermally coated stock. numerical comparison both series presented Table III. present the author standard- izing this experimental method for wire coated with tin,. cadmium, cop- per, nickel, etc. References (1) Auperle: Determination spelter coating sheets and wire (Pro- ceedings A.S.T.M., 1915; 15; 119). (2) Bauer: Determination thick- ness and grade zine coatings fer- rous articles (Mitteil. Material- 1914; 32; 448). (3) Bablik: Galvanization fer- rous matter (Paris 1927, 202-206). (4) Burgess: Investigation the properties zinc coatings (Electrochem. and Metall. Industry, 1905; 17; also Stahl Eisen 1919, 244). (5) Walker: Testing galvan- ized and other zinc (Proceedings A.S.T.M., 1909; 43). (6) Hall: Corrosion and Rusting Tests with sherardized forgings (Zeit- schrift Elektrochemie, 1913; 221). (7) The determination thickness and quality protective zinc coatings ferrous matter. (Proceedings Masaryk Academy Work, Praha, 1931, p. 31). Table Method Coating Zinc Electrolytically Thermally Diameter tested wire.............. 0.0788 in. 0.074 in. (2.00 mm.) (1.88 mm.) Length exposed wire.............. 1.472 in. Calculated 1.420 in. Calculated Amount pure zinc................ 0.00701 gm. 0.00188 gm. 0.00000 gm. Amount alloyed zinc............... 0.00340 gm. 0.00091 gm. 0.00113 gm. Total zinc, 0.01041 gm. 0.00279 gm. 0.00113 gm. Total zinc, chemical 0.00288 0.00165 gm. Amount iron alloy zone.......... 0.00290 gm. 0.00078 gm. 0.00094 gm. Thickness pure zinc 0.00422 mm. 0.00000 mm. Thickness alloy zone.............. 0.00143 mm. 0.00463 mm. Total thickness coating............ 0.00565 mm. 0.00463 mm. Above values obtained from determina- tions reported Table No. ........ Blast Furnace Operation Succinctly Described unusually clear and concise de- scription the iron blast furnace and its operation, written Joseph, has been published the United States Bureau Mines the form 29-page mimeographed pamphlet illustrated. designated information circular 6779, and be- sides its rounded out exposition the workings the blast furnace, es- says cover latest investigations having with improving perfor- mance, all the end apparently helping prospective builder blast furnace plant. Joseph styles the blast furnace heat generator, gas producer, heat interchanger, deoxidizing chamber and melting furnace,” and elucidates length how fulfils each these functions. summarizing, writes part follows: Trend Toward Ore Concentration The sizing ore and the charging three sizes (medium, fine and course) separately have proved ef- fective means obtaining more uni- form gas flow, lower fuel consumption and increased output. Such prac- tice can readily adopted about one-half the ore larger than in. For the fine ores the Lake Superior district, steps toward ag- glomeration will have accompany sizing the ore. Segregation fine concentrates and sintering the fur- naces are steps which have been taken one company toward better size preparation the ore. The physical characteristics coke have first importance. Coke, which has low bulk density the furnace, very desirable. This implies low ash content, uniformly large pieces with breeze small sizes fill the voids, and without sacrificing resistance abra- sion and size degradation han- (Concluded page 33) Table comparison electroplated and thermal plated zinc iron wire. The inter- mediate layer much thicker the case the thermal coated stock. These data are from graphs Fig. and the formula expounded this article. be : j 3 hey | gS { | which ‘nace, low pieces rosity abra- han- culated gm. gm. gm. gm. gm. Molding 30-in. Cast Sheaves from Pattern OUNDRYMEN general, and the jobbing fraternity particular, are occasionally asked customer whose account con- sidered valuable one, spe- cial favor the way producing few castings which are larger smaller size than any available pat- tern the design required. The cus- tomer’s knowledge the art mold- ing may very slight, some cases not any more than recognition the fact that stays foundry very long will need clean collar, the length his sojourn usually governed accordingly. has idea, however, that men who work sand things suit themselves, so, consequently, draws rough dimensional sketch, showing what would like, and; “you will probably able use our such and such pattern, now your possession; as, this being excep- tional order, with prospect pattern expense, etc., etc.” So, when order was booked for six sheave castings, each in. diameter, design shown Fig. from ex- cellent customer whose office and as- sembly plant were miles from the foundry receiving the order, effort oblige was necessary. The pattern nearest size the castings required measured in. diameter the base the groove, was plated design, with six strengthening ribs each side, and six lightening holes shown, and the castings requested were follow the same general contours, the hole, however, in. diameter in- stead in. With each the customer’s differ- ent sized patterns, numbering about EASTHAM eight all, complete circle corebox making full ringed half core was provided, two half cores thus dried separately, and afterward pasted to- gether, giving accurate results when properly calipered the time joining. The patterns were all metal one piece, excepting the core- prints, which were wood, fitted in, diminish the weight when handling. was first necessary in- crease the diameter the 22-in. pat- tern plus its outside coreprint the size required produce the 30-in. plaster paris was used make extensions pat- tern and core box when special order was received for casting larger than that for which any pat- tern was available here told detail. The successful experiment suggests possibilities the foun- dryman applications beyond the realm only emergency work. casting, bed was levelled the floor approximately ft. square, ordinary mold hardness, “topped’ with fine new molding sand, and struck off accordance with regular open sand molding practice. The pattern was then laid cen- trally the bed, and sweep which short rim segment was at- tached, dowel fitted into the center the hub coreprint, shown Fig. The segment, set the radius needed mark off the diametrical limit 30-in. casting, plus the es- sential gray iron contraction and coreprint allowances, then passed round the full circle, its outer face being lined with fine mold- ing sand, backed with heap sand, rammed level with the top. wooden frame appropriate depth and area placed the bed minimized the bulk sand han- dled and rammed. None the ex- cellent pattern substitutes the market being available the mo- ment, plaster paris was resorted the best material for the enlargement, suitable reinforcement being provided the use lace- work round iron rods, several which were hooped fit the full circle, their overlapping ends being springing open. Incidentally, the addition about per cent common salt the mix- ture when preparing plaster for mold dries the material quicker, and renders more durable. The sweep removed and the mold cleaned out, the plaster was poured; the rods were added between layers, the mold being filled quickly possible ensure cohesion. The top was then levelled off flush with the upper face the orig- nal pattern groove coreprint, and extension some in. was thus added the pattern’s total diameter. Preparation the mold for the full ring plaster corebox followed the same general lines, the corebox being cast with its face working side down, radial lines indicate the in- ner contours the corebox being first laid out the bed trammels operated from wedge knocked down the center the bed. The inner and outer walls the mold were The Iron Age, July 1934—15 — — — de- ace the the ited be- the es- ions for- f a nace zing and each ging and ef- uni- than Lake ag- pany fine size inter- from Fig. grooved semi-steel sheave casting in. diameter made from 22-in. pattern. then rammed pair seg- ments, passed round the case the pattern extension. The groove and print contours were molded from sections green core made from the 22-in. box, with- out rods, cut into short lengths and laid the mold the tram- melled lines; the slight increase the radius was effected means small segment cut out band- saw and laid the line, the cores being then spread easily their green state little judicious tool- ing the part the molder. The interstices the ends the cores were filled the usual way; bent wires bridging them inter- vals, with their projecting ends pushed down into the bed, prevented the displacement the cores when the plaster was poured. Extra re- inforcement the way old nails and cross wires, was added this unit enable the corebox stand better the wear and tear active operation. The drawing the finished core- box shown Fig. displays the light-looped handles cast four points, facilitate the withdrawal the box when making the cores. the same day, six ring coreplates were swept out opensand and cast iron, the familiar cupola lining block being used pattern section, with overhang inside and outside the full width the corebox pre- vent the plaster being chipped during the coremaking operations. The plates were “flowed off” thickness. this connection, when making the groove cores from the plaster equipment, soft ropes, tied three places around the box and coreplate when rolling them over, were used instead clamps, for obvious rea- sons. When sufficiently dry, the pattern with its plaster extension, also the corebox, were moved from their re- spective molds, given the necessary “touch up” with scraper, and shellacked, the six coreplates allowing three full sets cores dried the same time. certain point, the molding 16—The Iron Age, July 1934 Fig. and section views pattern and mold ready for plaster extension poured. each sheave was matter ordi- nary foundry routine, the pattern, surrounded its plaster extension, being laid flat board, the drag flask rammed up, vented, rolled over, and parting made, which the cope was rammed the usual way. little extra care was given the gagger arrangement view the fact that after the cope was lifted off, considerable weight sand was added order extend the plate, ribs, and inner contour the casting section behind the groove the re- quired diameter. This was when the molding process left the commonplace, and was ac- complished the use sweep, op- erated axially from dowel pin let into hole the center the upper half the hub pattern, which had been, usual, lifted away from the main pattern with the cope half the mold. means extending the six ribs both cope and drag, two loose ribs extending from the periphery the hub the shoulder the new diameter, were dropped into the rib Fig. 3.—Plaster core box for sheave in. diameter (at Left). Fig. 4.—Ring-type, cast coreplate in. thick maintain lightness. / \ \ | — - | 1 t h a Ww d ordi- tern, drag over, the way. the the off, was plate, re- rocess Op- let upper had from half six loose ery new rib Diameter Fig. half mold with sweep position, show- ing increased diameter right, original mold parted left. slots, the face the original mold the area built being then hold the facing sand pressed into the space between the ribs. The sweep was then pushed around, the built-up area was next nailed remove any risk drop when the mold was finally closed. Continuing this operation, the ribs were moved round, one time, al- ternately, until the circle was com- pleted, the outer ends the rib sticks forming excellent preliminary guide for the molder when building the sand before operating the sweep. The cope mold, with sweep position the right, and the mold appeared when hoisted off shown the left, well the nails necessary carry the extra load, are shown Fig. The diametrical extension com- pleted, the sweep was removed, the hub pattern drawn, and the mold given the few necessary finishing touches before plumbago coating and slicking. Alterations the drag mold were carried out exactly the same way soon the main pat- tern was drawn, hole the center the lower hub pattern forming the pivotal point the case the cope; the however, were omitted after the filling process being unnecessary. The original prints intended re- ceive the cores form the lighten- ing holes, left the pattern, were filled level with the face the mold. The new equidistant locations were marked off, and circular flat cores in. diameter were set position. nail pushed through hole the center each, addition the cope touch, held them firmly place when the castings were The actual coremaking from the plaster corebox needed little extra precaution when placing the rods, and jar the cores little before withdrawing the box the under side the coreplate was rapped lightly instead striking the box, this, course, avoid breaking the plaster. Sand cut away four places the back the print each half when pasting them, bare the outer iron ring, gave facilities for tying the halves together and also lower them into the molds without risk breakage. cross section view the closed mold with all cores placed given Fig. The increase diameter above outlined, raised the weight each casting from 145 270 gain selling weight around Fig. section view closed mold for 30-in. diameter sheave. 750 the order six, delivered mutual agreement six days after receipt the customer’s instructions. The net gain, apart from the rea- sonable cash profit, was, six handy coreplates added the general coreroom equipment, and, which was much more important, considerable increase the goodwill the cus- tomer toward the foundryman con- cerned, the result his willing- ness oblige. «a | j full-size brass rolling mill here shown being moved its concrete foundation crew from the American Brass Co., Waterbury, Conn., will feature the Ford exhibit the Century Progress Exposition, which opened Chicago, May 26. Capable producing the rate more than 25,000 Ib. sheet brass daily, the mill will continuous operation. The Iron Age, July 1934—17 3 industry and its development, with the definite fund knowledge and information procured through iron and steel, well metal-work- ing practice, remarkable change and growth ensued comparatively short period time. Plant layouts were rearranged provide for straight-line manufacture bath tubs and other fixtures from pattern shop finished storage and shipping. Cast Enameling the modern cast iron enameling plant, the castings are conveyed me- chanically the shaking pits, where the material freed from the molding sand, conveyed automatic sand blasters and thence the pickling baths. After leaving this bath, grip ground coat enamel applied the castings, which are then placed the enameling furnace means large iron forks. red heat, the enamel melts and flows into smooth, glassy surface. this point the tub castings are removed from the fur- nace and the enamel finishing coat applied. The latter operation han- dled swivel table, designed permit the worker turn the cast- ings any desired position. The electrically tamped sieve the end long rod. Experience and good judgment the part the operative are natural- required produce the fine enamel finish noted quality ware today. And can said further that such finish never would have been pos- sible under former methods manu- facture. Following, the tub castings are reforked into the furnace and the top finish coat enamel melted down. Several top coats are usually applied ware, and always best grade ware, give proper depth and desired quality finish. Sheet Steel Enameling cast iron enameling estab- defined basis improved technique, using the so-called dry process, out- lined, the next development and nat- ural one has been the porcelain enam- eling steel. Rapid strides have been made this line recent months. The research organizations number important steel mills have given thorough investigation the specific problems imposed enam- eling operations for the production sheet answer the requirements. Giving direct slant the possi- bilities steel enameling for different commercial products, the automobile industry has been demonstrating con- stantly the intricate and complicated 18—The Iron Age, July 1934 Wet and Dry shapes that can produced the highly perfected pressing and stamp- ing machines. Further, other lines, the development greater skill deep drawing, well the progress made welding, served make logical and practical consider the enameling numerous articles en- tirely out question with cast iron. course natural procedure, has become more and more understood that products should designed spe- cifically with respect the enameling process and this has gone expand and enhance the field manufacture steel-enameled specialties. There have been frequent instances prod- ucts giving unsatisfactory results when enameled, later determined caused improper basic design for such type finish. typical example the latter might cited the case tubs for LeROY ALLISON advances the art enam- eling iron and steel and the growth the enameling industry were traced some detail the washing machines, formerly made with welded barrel and bottom. When painted, this construction proved quite satisfactory, but when was decided for sales reasons give porcelain enamel finish the tub units, the initial results were quite the reverse. This led new design tub, now produced generally one-piece drawn steel construction, perfectly suited the porcelain enameling operation. The importance proper design from the standpoint the enameling plant quite well recognized the indus- Tor | 2 7 : Is of nam the the made When quite ecided celain the verse. drawn ted from plant indus- these two views enameled sinks the one immedi- ately above steel sink made the Youngstown Pressed Steel and that the facing page one cast iron. Enameling and MALCOLM CATLIN authors the issue June 21. The accompanying article de- voted the enameling both cast iron and steel. try itself, although the enamel jobbing plant engaging for variety out- side interests constantly receives or- ders enamel products obviously not all suited such type finishing Nothing seems illustrate more clearly the importance the power press the enameling field today and the future than the development the pressed steel sink. This now highly successful line manufacture comparatively recent origin, but sufficient extent demonstrate forcibly the progress being made the use what known wet proc- ess enameling steel. Two prominent manufacturers have entered into the production such sink units under mass methods out- put, the Youngstown Pressed Steel Co., Warren, Ohio, and the Briggs Mfg. Co., Detroit. This accomplish- ment the inevitable step manu- facturing evolution toward perfected product minimum material and weight perform given function doubtless followed other equally striking examples the future. Developments are progress for vitreous enameled steel bath tub pressed from single steel sheet, while lavatories similar base metal and finish are early prospect. Both these units, understood, will average per cent lighter weight than the conventional cast iron sanitary fixtures now the market. That this will lead the production similar large products enamel other lines certain. The possibilities seem practically limitless. Within the past year, close 100,- 000 pressed steel enameled sinks are said have been made and placed service. These units are about per cent lighter than corresponding sinks enameled cast iron today, and easily per cent the weight latter type sinks more years ago. This reduced weight pointed out definite advantage connec- tion with freight other transporta- tion charges, well handling and installation the job. With reduced manufacturing costs, the case the pressed steel sink, comes lower price level marketing, and this seems destined have its effect the cast iron unit. Further, safe predict that inroads will made the sales the heavy all-clay fix- tures similar character. Modern Sheet Steel Enameling Plant plant the Youngstown Pressed Steel Co. model its kind for sheet steel vitreous enamel- ing service. This company promi- nent for its extensive production pressed steel parts numerous va- riety. Likewise, important factor the manufacture enameled washing machine tubs, producing about per cent the entire output such units. Pressed steel enameled sinks have come natural develop- ment the further utilization plant equipment and facilities. The press department consists large battery heavy presses, the largest unit, resting 16-ft. con- crete foundation, weighing 160 tons and having ram pressure 1500 tons. With this press possible draw steel in. depth. The machine has normal rated capacity about 240 units per hr. Washing machine tubs steel sinks, the case may be, are drawn one opera- tion. Bending, turning, perforating and other special features design operation are handled smaller presses the shop. Washing machine tubs, averaging in. deep, are produced with ease, precision and speed from single steel sheets 18-gage material, and likewise steel sinks, appreciably less depth, but running in. long, from 14-gage steel sheets. The fabri- cation carried out entirely one piece, with welds seams any kind. There large pickling and clean- The Iron Age, July 1934—19 ing department this plant, with battery seven rubber-lined tanks. Under normal production schedules, the steel sheets are cleaned and pickled during the night, ready the next morning for cutting and press handling. The enameling plant contin- uous type, said the largest such plant its kind existence, with rated capacity 2500 units per day. This department the Warren plant represents investment about $250,000. Mechanical conveyors are installed for every feature oper- ation. The furnace installation con- sists one U-type, electric-operated continuous unit, with total routing length 160 ft., from the time the material enters one side and leaves the other side. The baskets hangers carrying the products enameled move the rate ft. parts are carried conveyor into gas fired enameling fur- nace the plant the American Stove Co. 20—The Iron Age, July 1934 per min., and are actually the furnace about min. The unit oper- ates 1600 deg. C., the firing zone. regular box-type enameling furnace recently has been installed the plant handle overflow material enameled. Two production lines have been ar- ranged the enameling division, making possible the enameling two separate products, such steel sinks and washing machine tubs, the same time. This special feature the plant and makes for noticeable economy manufac- ture. The products pass through four times for one ground coat enamel, two coats white enamel, and for acid-resisting coat respectively. The latter provides acid-resisting por- celain enamel finish exceptionally high quality. The pressed steel sinks are enameled all over and underneath, ERE are enameled parts being as- sembled into gas stoves roller tables the plant the American Stove Co. compared with the conventional sinks painted underneath. About different models these steel sinks are now being marketed the company direct plumbing material jobbers all parts the country. The finished sink units range size from 60-in. double drain- board in. flat rim sink, without drainboard. The flanges the sinks are turned under that rough edges will exposed. These sinks are sold under the trade name VEOS, formed from the type pro- duction, vitreous enamel steel. The sinks are being enameled white only the present time, with plans well developed manufacture the units number attractive colors later date, these corresponding the popular color shades the day. Special pressed steel brackets have | these rketed the range drain- sink, ges that These name pro- steel. white plans the colors day. have vogue enameling kitchen shown the enameled range, sink, table top and refrigerator. been designed hang the sinks from the wall installations. Enameling Development the importance the iron and steel industry the porce- lain enameling field has been empha- sized this article, the great advance the quality and durability enamel finish during the same time, brought about through the ingenuity, skill and research enamel chemists, worthy particular mention. This work has been primary factor developing porcelain enamel its present popu- larity. This phase the improvement may the progress made glass chemistry the past two three decades, for previously stated, enamels literally are nothing more than special types glasses. The modern knowledge and insight regarding the nature glass has made possible for the enam- eling plant apply scientific meth- ods the basic problem definite and absolute adherence the non- expanding glass the expanding metal base. Long ago those skilled enameling recognized the great advantage mechanization and close control the compounding and melting enamel batches, frit, and today operated enameling plant fine object lesson real technical effi- ciency. The recent advances made the field colored enamels have brought about some notable results this direction, securing increased at- tention the artistic flexibility ge - « bd * 4 ey a F = finishes. Here again research and experiments have taken leading part the devlopment. Architects, among others, have been attracted the possibilities the mass-produced enamel-steel units, large small sizes, the case might be, and plain decorated patterns. The late developments resistant enamels, likewise, has ex- panded the range application the material, eliminating the same time previous objection enamel finish under certain conditions service. Various kinds textured enamels, wood-grain effects, marbleized finishes and the like, all tend emphasize the adaptability and future encouraging prospects this versatile field, closely identified with the iron and industry. HEETS taken from the dipping tanks are passed into the furnace units here shown. The Age, July Co. Effect Heat the MURAKAMI and HATTA Tohoku University, dustries have greatly increased the requirements tool steels and multiplied the kinds steels used for dies. These types steels are widely used for drawing, forming, extrusion, punching, and the following prop- erties are generally required: (1) in- tense hardness without brittleness, (2) extremely high resistance abrasion, (3) comparative ease machining the annealed state, (4) minimum dimensional change and dis- tortion during quenching and (5) re- tention the required mechanical properties high temperatures. Since difficult obtain such variety properties with carbon steel there has necessarily been develop- ment steels containing chromium tungsten for die purposes. For many die steels the carbon content high about per cent, and among the alloy steels high-chromium high-carbon steels are most widely employed. recent developments in- spite the fact that there are numerous kinds die steels, there have been very few studies made con- cerning their properties. The present authors carried out comparative studies the change properties due the heat treatment six com- mercial die steels. The change the transformation points according the cooling rate was studied means magnetic analyses and differential dilatometric measurements. Further, the abrasion and hardness tests were made heat treated steels. forming and extrusion dies are often used high temperature, and the temperature die steel rises con- siderably due the friction even with cold working, the impact hardness and impact tests were also conducted high temperatures. this investigation six commercial die steels were used. Table shows the chemical analyses these steels: No. high-carbon steel, No. Iron Age, July 1934 low-chromium high-carbon steel, Nos. are high-chromium high-carbon chromium steel. investigation was made concern- ing the changes transformation points due maximum heating tem- peratures and cooling rates means magnetic analyses. The results these experiments are tabulated Table The high-carbon steel (specimen No. shows and transformations, but change the heating tem- perature rises, whereas they fall slightly the cooling rate increases. With the low-chromium high-carbon steel (specimen No. 2), only the Ar, transformation appears the case furnace cooling, whereas the case air cooling the trans- formation appears below 100 deg. general the transformation tem- peratures fall slightly with the in- crease the cooling rate and the rise the heating temperature. high- chromium high-carbon steels, such specimens Nos. each one shows slow heating Ac, point about 750 deg. which lower than the Ac, point, but the case furnace cool- ing the Ar, and Ar, transformations overlap each other and occur 740 TABLE the heating temperature and cooling Speci- Composition, Per Cent rate the transformation points very slight high-carbon steel and No. 1.. low-chromium high-carbon steel, but No. 4.. 1.98 12.64 0.26 0.91 No. 5.. 2.71 0.40 No. 6.. 1.59 1.77 1.10 TABLE Transformation Point, Deg. C.— Furnace- Furnace- Air- Air- Air- Speci- Cooled Cooled Cooled Cooled Cooled Cooled men Slowly From 900 From 1000 From 1100 From 900 From 1000 From 1100 No. Heated Deg. Deg. Deg Deg. Deg. Deg variations physical prop- erties different heat treat- ments commonly used die steels are recorded herein detail. The investigators not only have deter- mined the transformation points and hardness values the steels but have extended their investiga- tion include abrasion impact values high and low temperatures, and determination the softening point the steels. these data are taken 700 deg. and fall the heating temperature rises. Comparing the results air cooling irom 900 deg., specimens Nos. was found that specimen No. large A?’ transformation due the lower carbon content compared the others, and specimen No. the absence Ar’ due the high con- tent chromium and carbon. Tung- sten-chromium steel, specimen No. shows Ar: and Ar” transforma- tions when furnace cooled from 1000 deg. and 1100 deg., while markedly shows Ar” transformation when air cooled; this latter temperature falls the heating temperature obvious, therefore, that the effect | iy >» ating the » Ar’ lower the the con- cimen orma- air falls es. ooling nts and but —, 1100 Ary) 0(Ar’) 0( Aro) 0(Ar’) 0(Ar”) 5(Ar”) 0(Ar’) Properties Die Steels under conditions approximating those actual operation the tables should considerable value die makers enable them more confidently determine specific treatments for particular operation requirements. This in- vestigation was made Tohoku Imperial University and the data herein are rearrange- ment and abridgment paper which appeared the Science Reports that University mium high-carbon and tungsten- chro- mium steel. Since magnetic analyses impossible determine the trans- formation point when, the case high-chromium high-carbon steel, the point lower than the point, the method differential dila- tometry was employed détermine the points for the various steels considered this investigation. The results these tests are shown Table Variation Hardness order study hardness varia- tions due heat treatment, the speci. mens were tested with respect heat- ing temperature, cooling rate, temper- ing temperature and tempering time. The specimens were heated 900 deg., 1000 deg., 1100 deg., and 1150 been kept for hr. vacuum each the temperatures mentioned above. The tempering also was car- ried out vacuum, and the tempera- ture was varied from 100 600 deg. 100-deg. steps and the time for 10, 20, and min. The specimens were air-cooled after each tempering. addition, each die steel was an- nealed 650, 700, 750, 800, 850, 900 and 1000 deg. after being furnace- cooled from 900 deg. and the hardness measured order study the re- spective softening temperatures. Rockwell hardness tester with diamond cone using load 150 kg. was used for these measurements. Table there are shown the re- sults obtained the specimen measuring the change hardness due the heating temperature and cool- ing rate. From these results can seen that the effect the heating temperature slight for furnace- and air-cooling, and the heating tem- perature rises the hardness increases small amount. the case oil- quenching, however, the effect very remarkable. Both for furnace-cooling and air-cooling each specimen shows that the higher the heating tempera- ture the greater the hardness number. This caused the fact that the normal transformation ficulty whereas martensite easily TABLE Transformation Point, Deg. C. Speci- > Slow] Slow] deg. (especially for specimens Nos. Heated Cooled ; Yo, 2 7 785 730—~ 692 cooled oil-quenched after they had 791~ 848 810 — 725 791 850 810 — 725 No. 6....... 735 765 738 680 TABLE Rockwell Hardness (C-Scale) Heat Treatment No. No. No. No. No. No. Furnace-cooled from 900 deg....... 40.3 41.5 39.3 38.3 48.3 Furnace-cooled from 1000 deg....... 41.6 43.2 41.6 40.2 38.3 49.1 Furnace-cooled from 1100 deg....... 39.1 48.3 42.6 41.1 42.3 52.3 Air-cooled deg............ 42.5 45.3 42.6 42.5 40.7 56.4 Air-cooled from 1000 deg........... 43.6 47.2 46.6 47.6 48.4 61.4 Air-cooled from 1100 deg............ 46.3 49.0 46.8 48.6 48.2 62.4 Oil-quenched from 900 deg.......... 68.0 65.4 63.3 63.1 65.3 Oil-quenched from 1000 deg.......... 59.1 60.0 68.3 64.2 66.7 54.0 Oil-quenched from 1100 deg.......... 58.5 43.8 62.7 58.1 60.7 44.5 Oil-quenched from 1150 deg.......... 51.2 48.6 48.5 formed the Ar” transformation point the heating temperature rises. oil-quenching the decrease hard- ness, except for high-carbon steel, heating above certain temperatures results from the increase residual austenite. Therefore should no- when studying the effect the cooling rate that the hardness not always high with rapidly cooled specimen; further, the hardness the air-cooled specimen always higher than that the furnace- cooled, while the case the speci- men oil-quenched from above 1000 deg. the hardness lower than that both the air- and furnace-cooled specimens. order study the influence tempering, the hardness changes wer