The Iron Age 1935-11-14: Vol 136 Iss 20

CHESTNUT AND S6TH STREETS, PHILADELPHIA, PA. Sales Offices 239 WEST 39TH STREET NEW YORK, Owned, Published and Copyrighted CHILTON COMPANY (Incorporated) Executive and Publication Offices, and Sts., Philadelphia, MUSSELMAN, President FRITZ J. FRANK, Executive Vice-President FREDERIC STEVENS, Vice-President JOSEPH HILDRETH, GEORGE GRIFFITHS, EVERIT ERNEST HASTINGS, WILLIAM BARBER, Treasurer TOHN BLAIR MOFFETT, Secretary FRANK, President VAN DEVENTER Editor Managing Editor News Editor Machinery Editor Editor Emeritus Washington Chicago Cleveland Detroit Boston Cincinnati 14,1935 Non-Metallic Impurities Open-Hearth Oil and Grease Lubricated Micarta Crankless Power Presses for Auto Body Stampings....... Beneficiation Low Grade Large Welder for Aluminum Alloy Airplane Parts....... Construction and Equipment Buying. BAUR, General Advertising Manager DIX, Manager, Reader Service Member, Audit Bureas of Circulations ADVERTISING STAPF Member, Associated Business Papers Emerson Pindley, 311 Union Bidg., Cleveland B. L. Herman. Ave., Buffalo, tion Price: United States and Pos- Peirce Lewis. 7310 Woodward Ave.. Detroit sessions, Mexico, Cuba, $6.00; Can- Charles Chestnut ada, $8.50, including duty; Foreign Sts.. Philadelphia. Pa. W. B. Rebinson, 428 Park Bidg., Pittsburgh W. C. Sweetser. 239 West 30th St.. New York $12.00 a year. Single copy, 25 cents. ‘ se : 4 re 4 3 4 Steel Guide —Just Out For years the Ryerson Stock List has been recognized the Key Immediate Steel. you are sure find the kind, quality and size material you require. Copper, Brass, Babbitt and allied lines are included. This edi- tion shows the new extras hot rolled and cold drawn bars and makes easy accurately fig- ure prices. Many useful data tables are also this book. Keep hand and when you need steel call Ryerson for ment. This new edition has just been mailed. you not receive your copy, write and will send it. Joseph Ryerson Son, Inc., Chicago, Milwaukee, St. Louis, Cincin- nati, Detroit, Cleveland, Buffalo, Boston, Philadelphia, Jersey City. RYERSON 16—THE IRON AGE, November 1935 63 63 ‘ THE IRON AGE... NOVEMBER 14, 1935 ESTABLISHED 1855 Vol. 136, No. Not food for thought for the wealth sharers and also for the people who elected them office. During the years from 1924 1933, the half million incorporated businesses the United States reported collective net income averaging little under billion dollars per year. fair average take for our purpose, since six these years fell the boom period. these profits had been conscripted and divided among our forty million gainfully employed people, would have raised each one's wages just per year. Figure out for yourself. That one way share wealth. But would mean adopting state socialism com- munism, junking the Constitution and regimenting everybody under gang political bosses. There was practical and much more simple way achieve much greater wealth sharing. The practical men who built the Democratic platform knew that way and made plain pledg- ing per cent reduction cost Government. Believe not, that pledge had been kept would have saved enough raise the wages our 40,000,000 workers each per year. Five and three quarter billion dollars would have been available divide had cut per cent from the $13.4 billion cost Government, was 1932 when that pledge was made, and had held there. that the difference between the total cost Government, Federal, State and local running now and would have been now were operat- ing rate per cent below the level. more per year nice sum anybody's pocket and how would increase the consume" that the professors talk about! This practical form wealth sharing that can put into effect without revolution, without regimentation, without bullets, but simply through ballots. American citizens should give considerable thought. Because the many requests for reprints appearing the publishers have ar- ranged make such reprints available any quantity desired price representing cost production and mailing. Please address Reader Service Department, AGE. 3 | | | | : | | 1902 1904 1906 1908 1910 1918 1920 1922 1924 CHART Stee/ Lehigh University nr oo Per Cent 1928 How Can the Growth the Steel Industry one time pig iron was almost universally accepted the mea- sure growth the steel industry. more recent years, however, pig iron does not well represent this growth. With the passing the years, finished products made iron have been replaced finished products made steel. This shown Chart the precipitous decline the line representing the per cent rolled iron rolled steel. 1929, rolled iron amounted only little over per cent the fin- ished product, and since 1931 has been less than per cent. IRON AGE, November 1935 Iron now almost entirely raw material. Scrap also raw material, but its use has grown more rapidly than the use pig iron. This the reason why pig iron does not well represent the growth the steel industry. Be- cause the inadequacy pig iron, production steel ingots has come into wide use represent the growth the industry. Since practically all the finished prod- uct steel, production steel in- gots well represents the activity the industry the present time. Nevertheless, the production steel ingots does not well repre- sent the growth the industry. This can seen examining Chart where the growth steel ingot production compared the growth total rolled iron and steel production. will seen that steel ingot production farther above total rolled iron and stee] production today than was years ago. The reason not hard find. virtually the same the reason pig iron unacceptable measure growth. Although steel now virtually complete representation the in- dustry, has been becoming more and more complete represen- tation. Hence, using steel ingot production, obtain growth | c | | ¢ 8 | ” 5 4 | ] fy H | H ° ° ° | & . a | made two parts: (1) the growth the industry, and (2) the shift from iron steel the finished product. Finished Product Data More Representative can largely avoid the inade- quacy involved using pig iron steel ingots represent the growth the industry going directly data representing the production the finished product. For years the American Iron and Steel Institute has compiled rela- tively complete total rolled iron and products. The are relatively small, and, what more important, these omissions have not become any more less significant over long The writer estimates that the total fin- ished product the industry has run around level about per cent higher than that shown the “total” rolled iron and steel products series the American Iron and Steel Institute, all products the industry are considered, including castings and major proportion forgings, will raise the level slightly. However, the proportion- ate increase level, the are omitted (1) iron and steel castings, (2) iron forgings made rolling mills and steel works, and (3) such steel forg- ings are made from steel ingots, but not made from steel billets, sold the steel companies. There are available data the first and second these items, and their growth very similar that total rolled iron and steel. Population Index Millions People TABLE Year Ratio Year Ratio Year Ratio Year Ratio 1904 -758 1912 .760 1920 .758 1927 .T38 1905 1913 1921 1928 1906 1914 1922 1929 1907 .783 1915 1923 1930 1908 1916 .738 1924 1931 1909 1917 1925 1932 1910 1918 1926 1933 1911 1919 The level this ratio 1932 and 1933 due temporary influences. Ap- there was depletion inventories steel ingots 1932 and re- assembly such inventories 1933. growth, correctly portrayed the American [ron and Steel Insti- tute comparison the ratio rolled production bears steel in- got production discloses another, although minor, weakness steel method adding the tons the various rolled products together, for both steel and iron products, open criticism ton one prod- uct judged more important than ton another. What such weights should would difficult, not im- possible, decide adequately. Since rolled steel has become successively more important, noted that important than ton rolled steel, small artificial growth factor in- troduced. any event, this factor could not great that which oc- curs the case steel ingot produc- tion, for there rolled iron disre- noted that neither pig iron nor steel ingots avoid this weighting they are such early stage the process that the need for weights for various products not obvious. noted that the methods used the Institute not add twice occur when billet further Iron and Steel Production CHART ingot production when used rep- resent growth. This ratio pre- sented the accompanying table. The tons rolled steel produced has never varied greatly from three-fourths the tons ingots produced, except during the World War This larger accounted for several factors: (1) Croppings must clipped remove the pipes from the steel before rolling; (2) small propor- tion the rolled steel rejected the purchaser; iron oxide chip off the rolling proc- ess; and (4) Part the forgings are excluded from the rolled steel figure the process compila- tion, although the steel used in- low level the ratio during the World War years ex- plained the large quantity forg- ings, such projectiles, produced for war demand. large proportion these forgings not included the total rolled iron and steel series, noted footnote Forecast, Rolied Iron and Index Millions Long Tons THE IRON AGE, November 500 1850 1890 1900 1920 1930 1940 1960 1970 cluded the figure for steel ingot production. The first three these factors are technical ones creating scrap which will thrown back into the steel furnace. The fourth factor results from slight in- adequacy the rolled steel figures. far the most important are the pipes and non-uniform portions which must clipped from the steel. the trade customary allow for the loss fourth the ingot from this The only factors which have be- come successively more important the years have passed are steel rejections and oxide scales. The re- Iron and Index ,millions long 1900 1904 1906 1908 1910 quirements the purchaser rolled steel have become more stringent, resulting slight in- crease rejections. larger pro- portion steel rolled into light- rolled products than formerly was the case, resulting slight in- iron oxide scales. This slight increase the relative pro- portion rejections and iron oxide scales causes the slight de- cline the ratio rolled steel steel ingots. This decline can noted examining Table For the 10-year period 1904-1913, the ratio averaged 0.769, while for the years 1920-1929 the average was only 0.742. This means that, because increasing rejections and the shift lighter rolled good statement the technical reason for the existence pipes, to- gether with photographic reproduc- tions them will found Bradley Stoughton, The Metallurgy Iron (McGraw-Hill, 1934), pp. 20—THE IRON AGE, November 14, 1935 194 1916 1918 1922 1924 products, steel ingot production shows another, although minor, ar- tificial factor growth not related the growth the steel industry. Decline Accentuated The seriousness the charge against steel ingots represen- tation growth the steel indus- try rests upon the fact that steel ingots accentuate the decline which has been taking place the rate growth. Judgments about the fu- ture rate growth are over- pessimistic, therefore, when gained from analysis steel ingot pro- duction. From casual glance Production Index Manufacturing CHART Chart this might not appear the case, since steel ingots get successively farther and farther above rolled iron and steel. But this increase took place almost entirely the World War. Chart drawn ratio scale and therefore the distance one line above another indicates the pro- portionate difference size the items represented. The distance between the lines remains almost the same from 1919 1929, al- though increase spread was marked the World War. will seen, therefore, that the downward concavity steel in- gots greater than that rolled iron and steel. accept the rolled iron and steel series the best representa- the growth the industry, will necessary have the data over long period into the past. The American Iron and Steel 1926 Institute’s compilation total rolled iron and steel products runs back 1887. For the earlier years, however, acceptable use pig iron and ferroalloy production represent the industry. Data pig iron and ferroalloy production are available back 1854. Use pig iron represent the industry this earlier period does not in- volve the shortcomings found its use later date. Practically all the finished product was iron. raw material. reducing pig iron and ferroalloy production, 1854-1887, percentages the 1887 figure, and multiplying the re- 500 sult the 1887 figure for total rolled iron and steel production, the writer has con- structed duction rolled iron and steel, 1854 This series presented Chart II, plotted against the growth population. will seen that the steel industry curve much more rapidly than the popula- 1928 tion curve, indicat- ing the substantial per-capita increase the demand for steel. Although thus possible obtain. picture the growth the steel industry for more than years, the growth the early part this period probably not very significant to- day. The position iron and steel basic raw material for the prod- ucts vast number industries expanded greatly the end the nineteenth century. From virtual (CONTINUED PAGE 88) Base 1926-1930 Pearson Warren Base the Snyder and The Day-Persons series acceptable for repre- sentation the growth the industry only and does not give the best actual estimate obtainable for any one year 1854-1886. Howard Cook made es- timates for 1885 and 1886 which differ from the figures shown Chart about per cent. Total rolled iron figures are available back 1864. These figures are above the estimates shown Chart 1864, 1865, 1866, and 1871; this discrepancy probably due the fact that more pig iron went into inventory than occurred the case rolled products. The effect using pig iron production repre- sent the industry the early years weight iron and steel products proportion the difference con- version ratios. 30 4 | { CLAYTON BURT, President, Pratt Whitney Co. Drawn John Frew for The Age. . / “4 3 il q FY a a | | } Non-Metallic Impurities Steel comparing the prod- uct the extremely small open-hearth fur- nace with that the tonnage unit, one generally attrib- utes the marked difference quality different speed oxi- dation and the possibility the part the smaller unit closely supervise the selection and inspec- tion the raw materials well the various steel-making phases. Several attempts have been made partially close this gap re- gard quality. And the studies the relationship between the speed oxidation and the presence non-metallic impurities the bath have disclosed some very in- teresting data. the light these findings one gains not only closer conception the impor- tant function the basic open- hearth slag principal regula- tor this speed but also clearer understanding the desirability having the working methods em- ployed the quality and quantity units distinctly separated. known fact that certain chemical reactions steel bath produce entirely different surface disturbances commonly called boils, and these phenomena also mir- ror the main means which the non-metallic inclusions enter the bath, they offer perfect approach the subject dealing with the above mentioned relationship. short, there are three types boils, two which are directly traceable the oxidizing agents fed into the furnace, and which for the sake convenience one may ° ° FOLKE SUNDBLAD River Rouge, Mich. ° ° call (1) lime boils and (2) iron ore boils. The third kind boil, the so- called bottom boil, sharply distin- guishes itself from boils (1) and (2) appearance. While both the lime and bottom boils are limited certain spots the surface, the former easily recognized its violent, sputtering performance and the latter its rolling action. The iron ore boils, the other hand, are not localized, but cover the whole surface. Slag Fluidity Influences Oxidation all three cases the shape the slag plays major role. thin slag, course, offers less interference than heavier one the direct and indirect heat the flame, well the natural tendency the gases formed the bath reach the lighter pres- sure area above, caused the fur- nace draft. thinning out the slag, the bath will not only absorb more heat, automatically increas- ing the speed the ascending carbon monoxide and dioxide bubbles, but the slag itself will also lose some its power pro- tect the metal from direct reaction between its carbon and the oxygen the air. Therefore, the speed oxidation materially direct proportion the fluidity the slag. This relationship becomes special significance when making large high-carbon heat deoxi- dized the furnace, because explains one the main draw- backs the tonnage unit when attempting make high-quality steel according present methods. account the well known characteristic lumpiness high- carbon basic slag, the proper shap- ing which naturally necessitates the feeding large quantities fluorspar, the oxidation the car- bon, for the above reasons speeded up, while the slag being transformed into one instead the desirable velvet type slag. the moment the bath being “killed,” obvious that ab- normally great amount solid oxides, etc., will arrested the steel. However harmful this de- large unit, the most detrimental effect upon the quality undoubt- edly due the great depth the bath, which makes necessary maintain comparatively high tem- perature the metal order minimize the difference between bottom and surface temperatures. This condition, turn, multiplies the chances having bottom trou- ble, thus releasing great quantities non-metallic particles. Conse- quently, instantaneous deoxida- tion large bath likely entrap fcreign impurities far greater extent than what the smaller unit produces with low temperatures and slow oxidation. Additional light upon the seri- ousness this result gained study the above mentioned so- called bottom boil. The direct causes thereof are primarily phy- sical nature, the attack upon (CONTINUED PAGE 76) THE IRON AGE, November ; 3 j yg ri FIG. used testing bearings. view the results obtained all types metal rolling using water carta bearings, was natural that effort should made develop something along the same line em- ploying grease oil lubricant. This was tried early the bearing development but ordinary types laminated phenolic materials are not satisfactory for this type service, and there tendency lap out layers and heat beyond the safe operating temperature. new process these difficulties have been eliminated and today entirely possible apply Micarta bearings according the standard design for the babbitt brass bearing but with advantages in- herent the laminated material. 22—THE IRON AGE, November 1935 extensive series tests was made under accurately controlled conditions using equipment pic- tured Fig. rotating shaft directly driven calibrated motor which the input field cur- rent can measured. The bear- ing inclosed metal housing and pressure applied taking the nut the top the frame- work. The measures the total pressure ap- plied. Checks are also made other variables such the per- ipheral speed shaft, temperature rise the bearing itself, these data the coefficient fric- tion calculated and plotted against the speed the shaft un- der various loads. Two these graphs showing direct comparison between the Micarta bearing and and Bearings HORNE Westinghouse Electric Mfg. Co. the babbitt bearing under and Ib. per square inch loading re- spectively are shown Fig. and Fig. Data were obtained sev- eral intermediate pressures, well higher than those shown, and gave approximately the same dif- ference frictional properties be- tween the Micarta bearings. course, the higher pressures consistently show lower frictional coefficient. Water lubrication Micarta bearings gives low frictional co- efficient higher speeds but hardly practical speeds below ft. per minute. The grease-lubri- cated Micarta bearing, however, very satisfactory this lower speed range. was found possible operate Micarta bearings for much longer 4 =" | 7 4 ome d | time after failure the grease oil supply. This doubtless due the slightly absorbent quality the cloth retaining portion the lubricant. was noted that after failure the lubricating supply the Micarta bearing could oper- ated for approximately hr., compared with less than hr. for the babbitt bearing. During the period operation without lubri- cant the shaft running the bab- bitt bearing was quite badly scored, whereas scoring any kind occurred the shaft next the Micarta bearing. This im- portant point when the cost tearing down machine and turn- ing scored shaft considered. Trials are being made the present time employing this type bearing both small and inter- mediate electric motors. Here the advantages are not much fric- tional, but rather reduction vibration transmitted. This important item, many motors are thrown out final inspection for this defect, which practically obviated the use material the bearings which dampens vi- bration. Numerous other possibili- ties suggest themselves for bear- ing this type and test work being continued order deter- mine any limitations. date, how- ever, the field pressure and speed covered the above outline Large Gear large cement mill drive, the weld- steel herringbone gear blanks here illustrated were cut and fabri- cated four days. The material for the blanks was first cut pantograph type oxy-acetylene cut- ting machine, then bent and formed suitable equipment the plant, and finally are welded. The outside rings were formed from 4%-in. plates and the spokes plates were cut from 1%-in. plates. The spokes were fabricated form I-beam cross sections, also were the rims which the gear teeth were cut. The hubs are steel castings. The fabricated blanks were in. diameter and the net weight each was 7647 The photograph and data are reproduced cour- tesy the Air Reduction Sales Co., New York, whose cutting machines were used for this work. The weld- ing was done with Wilson arc- welding machine. Bearing Pressure Grease Lubrication 200 250 300 380 400 450 600 Shaft Peripheral min Bearing Pressure 0.030 Grease Lubrication le 0.025 100 150 200 250 300 400 450 500 Shaft Speed, min would appear that Micarta bear- application where grease ings can applied successfully brass babbitt bear- and good advantage any type ing now used. Blanks Made Welded Steel THE IRON AGE, November 0060 0040 Crankless Power the automotive in- dustry, the development recent years toward simplification oper- ations has led the welding to- gether stampings the type that ordinarily required extensive hand-finishing. The ultimate goal was make these larger units few stamping operations pos- sible order minimize elimi- nate the costly hand-finishing work. Another result desired and ob- obtained this procedure was 24—THE IRON AGE, November 1935 that large automobile body parts made one die attain uniform- ity which materially reduced the time, and therefore the costs assembly. The net result the development speedier production with lower costs and much better finished job. Larger and Better Deep-Drawing Stock Several problems had solved, however, before these large stamp- ings could made: First, the size press designs called for crankshaft running through the center line the press from right left. Presses for Making steel sheets suitable deep- drawing stock had increased. first this was problem for the steel mills but one which they are now overcoming rapidly and very successfully. Also, the deep-draw- ing quality the stock had improved make deeper draws possible while retaining the smooth surface the steel, thereby elimi- nating costly polishing operations. the rolling these large sheets, the question evenness and thickness over the entire sheet became even greater importance than sheets smaller size. Variation thickness the edges and the center the stock con- stituted difficult problem for the steel producers, but had corrected because the obvious difficulties caused that condi- tion properly spotting and fit- ting the dies. Also, resulted much waste due breakage and increased cost metal finishing because the variations and ir- regularities the surface the metal. Constant research and improve- ment the equipment the steel mills have made possible, how- ever, furnish the automobile in- dustry today with the material re- was necessary the metal the bot- tom the stroke keep from spring- ing out shape after the drawing operation was com- pleted. NSS ° ° GLASNER ent, Clearing Machine Corpn., quired for the production these large panels. Dies for Larger Panels Problem The second problem was one which the automobile makers had solve themselves: namely, the division the body into fewer and large panels and the production dies capable handling them. The body die makers were equal the new demands upon them and the evolution that industry, extend- ing over many years, has opened ever-widening range for the au- tomobile body designer, that stampings depth and size which would have been almost impossible produce several years ago are being successfully pro- duced one operation. Being able now obtain suit- able sheet steel and haying learned build dies which would produce the large units, big stamping shops were confronted with the addi- tional serious problem procuring presses capable utilizing the new dies and the larger sheets their full possibilities. Most the press equipment installed these plants was originally designed for the production smaller pieces, but more important even than the size the equipment was its in- adequacy from the standpoint accuracy and power application necessitated this new develop- ment large stampings. Larger Presses Not Whole Answer Merely increase the size the presses was not the answer. One the chief difficulties with the older press equipment was that the slide the press carrying the upper die would not remain par- allel during the entire stroke (par- ticularly the bottom the stroke), which made accurate work difficult and often impossible. trend automobile body work has been toward fewer stamping oper- ations, and this trend has brought new demands sheet mills, body die makers, and press builders, well auto body plants them- selves. Mr. discusses these demands and how they have been met, and describes detail new crankless power press developed for auto body and other large work. this press, each corner the slide has its individual drive from the press motor and flywheel. bull gear cast integral with eccen- tric mounted over each corner the slide, ar- rangement said result both direct transmission power and absence ex- cessive torsional deflection. The uneven pressure distribution required over large areas rea- son the various odd shapes the stampings made absolutely necessary that the lower face the press ram remain with the press bed under these uneven load conditions. Particularly was this apparent the case dies considerable width from front back. The type press generally used that period was driven from crankshaft running through the center line the press from right left, with the pitmans connecting the crank with the slide actuating the movement the slide the center line. (See Fig. 1.) With this type press construc- tion, became problem elimi- nating tilting the slide when high pressure must exerted either the front the back the stamping. obtain uniform stampings, was necessary “set” the metal the bottom the stroke keep from springing back out shape after the stamping drawing op- eration had been completed. This was especially important where beads the stamping had set down sharply and where these beads were unevenly distributed over the face the part, particu- larly cases where such beads oc- curred only one side the (See Fig. 2.) Not only for reasons accuracy and uniformity the work was desirable produce sharp bead, but also for the sake finish and appearance. Crank-Operated Four-Point Presses The first press used for automo- bile body work built the four- point suspension principle and ac- tuated four connections, one each corner the slide (Fig. 3), was developed under the supervi- sion and direction the writer. This press still daily tion one the largest plants the automobile industry. This principle won immediate recognition among the users this large type press and within short time presses embodying became widely used large plants the United States and other countries for work this nature. was first used only single- action presses, and thus employed, the four-point suspension principle actuating the slide solved many difficulties for the die designer and pressed metal production depart- ments. While presses with the slide actuated two parallel crank- shafts were distinct advantage over the design with single crank- THE IRON AGE, November > i Chicage corner the slide. shaft the center the slide, the problem equal power distribu- tion each corner the slide, and also the elimination bending, however slight, the shafts under high pressures, presented inter- esting subject for press engineers. The constant advance quality and uniformity the large sheets which were now being pro- duced, and also the forward steps die design threw the problems the production accurate stampings squarely into the lap 26—THE IRON AGE, November 1935 3—The four-point suspension press actuated four connections, one each 4—Each corner the slide the crankless press has symmetrically distributing power from central point. the press builder. had adapt his equipment meet many new conditions. Deep draws one side the stamping, sloping shallow curves the other side, might one condition, the set- ting the material the bottom the stroke the press per- haps only one corner the stamp- ing might require that the fact excessive torsional deflection the crankshaft (or the deflection the press under load) mini- mized. The problem torsional its individual drive ous one. Constant shocks and the twists developed handling the present-day type work cause fatigue the metal, resulting all too often broken crankshafts. Crankless Press Everyone familiar with the high-pressure demands periods peak production the automo- bile industry will realize that such interruptions production lines, say nothing the cost re- | pair, constitutes one the weak links stamping shops. obvi- ate these difficulties, which are most serious when the crankshafts break the large presses, the principle crankless presses (Fig. was developed. The Clear- ing Machine Corpn., Chicago, has developed type crankless press sence excessive torsional tion. Eccentric Integral With Bull Gear Integral with the bull gear, one solid steel casting, eccen- tric, varying diameter according the stroke requirements the slide, and this eccentric and bull 6—The bull gears are directly over the four corners the slide. addition direct transmission power, the arrangement features absence excessive torsional deflection. which now being used success- fully for the type work which speak. (See Fig. 5.) this type press, each cor- ner the slide has its individual drive symmetrically distributing power from central point, name- ly, the motor and flywheel. The bull gears, which presses older design were usually mounted the ends the driveshaft the outside the press, rectly over the four corners the slide the new crankless press (See Fig. 6), resulting direct transmission power and the ab- gear revolve over non-rotating, large pin. (See Fig. 7.) This pin mounted each side the walls the press crown that instead there being twisting action this pin, which carries the load, loaded straight shear, each side the eccen- tric. This construction makes possible shorten this load car- rier pin, bringing close the eccentric, thereby almost entirely eliminating the problem tion this member. Combining the main bull gears with the eccentric into one steel casting eliminates any need for the keys ordinarily used crank- shaft presses for the driving the crank. (See Fig. 8.) From the foregoing evident that the gearing the crown all within the boundary the tie-rods and directly over the actuating mem- bers for equal and direct power distribution. For actuating the up-and-down movement the slide, the eccen- tric carries eccentric strap, the lower end which transmits the motion the slide. This construc- tion makes possible eliminate split bearings, the eccentric strap being made solid one steel cast- ing, bronze lined. The square-inch pressure loads these main bear- ings are, therefore, very low be- cause the large surface obtain- able this type construction. Slide Guidance Not Entirely Dependent Gibs still further and assure against tilting the slide, these are designed that the slide guidance does not depend en- 5—Numerous new requirements stamping work impose real problems the press designer. THE IRON AGE, November 1935—27 | 4 4 tirely the gibs which are fas- tened the uprights the press. the first place, all four gibs are made adjustable, instead the two fixed gibs ordinarily provided. This, itself, provides added feature accurate alinement for the slide. addition the gibs, the con- nection screws the four corners the slide, which provide for its vertical adjustment, are extended through suitable bronze bearings the lower side the crown. 8—Main bull gears and eccentric combined into one casting elim- inate the use keys. Guiding the upper end these connection screws these bronze bearings set the crown provides accurate guiding for the slides, in- stead depending for its guid- ance the gibs alone. The gibs have maintained loose enough position, course, with sufficient clearance for free movement, only the gibs were used for guidance the slide 28—THE IRON AGE, November 14, 1935 the accuracy its alinement would not precise the above method, with its additional guiding the slide the solid crown the press, the upper end the connection screws. slide single-action press par- allel with the bed the press, follows that the case double- action press, parallel alinement both slides with each other and with the bed the press still more important. with the bull gear, one solid steel cast- ing, eccentric. hold the blank accurately and exert the correct pressures the draw ring, the advantage using the four-point suspension ciple the blank holder slide has long been recognized, and four ad- justment screws, one each cor- ner the slide, have been em- ployed for this purpose for many years. depend entirely upon gibs be- tween the inner and outer slide hold the inner slide parallel does not give perfect results. far more accurate and dependable means obtaining parallel posi- tion the slides during operation the four-point suspension prin- ciple power press drive. actual experience, double- action and triple-action presses thus constructed, with all slides guided each the vari- ous slides, have resulted great accuracy for the stampings and less wear the dies. Oil Receptacles Simplify Lubrication The construction press crown the manner described above provides oil receptacle for all the rotating parts the press, practically eliminating the problem burned out bearings and greatly simplifying lubrica- tion, which important ma- chine parts subjected intermit- tent high pressures, the case the parts large power press. this way dependence oil feeders forced grease lubrica- tion eliminated and long life the vital working parts the press assured. What this means the maintenance equipment | % ‘ | i | S — } | ABOVE suspension offers accurate and depend- able means obtaining parallel position. can readily surmised. elimi- nates the problem depending upon the uncertain human element connection with lubrication, par- ticularly the large shops where great number units would otherwise have attended con- stantly. For quick visual check, desired, sight glass provided showing the level the oil, which needs changed only occa- sionally. the lower end each connec- tion screw where connects with the slide, slide adjustment gears are provided, and assure posi- tive and accurate alinement the four corners, individual adjust- ments for each the screws are supplied, which makes possible aline each corner individually means finely graduated but rigid adjustment devices. (See Fig. 11.) Slides Counterbalanced Pneumatically Because the increasing size the dies used connection with these large body presses, the ¢ slides are counterbalanced means compressed air cylinders for smoother operation and protec- tion against drop the slide brake failure. The air pressure can regulated suit the various die weights and compensate for variations the weight the moving parts the press. (See Fig. 4.) the upper end the con- nection screw bearing which the lower end the eccentric strap swivels, These four cylindrical bronze bearings the bottom PAGE 74) BELOW each corner. THE IRON AGE, November 14, 1935—29 4 | 3 if { § | i | | inn THE Class ore very small proportion the total ore occur- ring the Mesabi Range, and the Class ore has been about one-half used up, while the Class and Class ores have hardly been touched. Just how much longer the Class ore will last depends upon how fast mined, but evident that the Class and Class ores together will last almost indefinitely. The future reserves the Mesabi Range, therefore, lie largely the Class and Class ores, and these materials must utilized the important iron mining district. High-Grade Ore Will Last Only Years Testimonies given various ex- perts the mine tax valuation case Duluth last summer agreed quite closely that the life the merchantable ores the Mesabi Range was from years. These figures are computed the the future. The other mining regions the Lake Superior dis- trict will probably exhausted sooner than the Mesabi Range. Obviously this not life suf- ficient length satisfy those who have made enormous investments railways, steamships, blast fur- naces, steel plants, and all the associated fabrication and manu- facturing indystries, together with the various cities and towns, all which combine form the greatest industrial development the world. Consciously uncon- sciously recognized that the low-grade ores which abundant, especially the Mesabi Range, will furnish the ore supply required the future, supply far greater and more important than the reserves the high-grade ores the present. knew that the end 30—THE IRON AGE, November 14, 1935 DAVIS Superintendent, Mines Experiment Station, University Minnesota ° years the iron ore the Lake Superior district would exhausted and that all the indus- tries which exist only because this ore would cease exist, the future would indeed look dark, not only the steel makers but the general public well. The reason does not look dark because believe that the low-grade ore can utilized for the manufac- ture steel cost which will compare favorably with the cost producing steel from the high- grade ores. Smelting Practices Must Improved New developments which must made before the low-grade ores can utilized economically cannot all made ,the mining and beneficiation operations. The smelt- ing and refining operations must also improved. There reason believe that the present blast furnace has now reached state perfection beyond which will never advance. Just which direction these new developments will take cannot stated, but certain that the ore-producing industry the future will quite different basis from the ore-producing industry the pres- ent time. When the direct furnace ore exhausted, concentrate will the product sent the smelting plants; the blast furnace operators will longer able specify the kind ore they want; will necessary for them develop means for smelting the kind ore which can furnished them. There ample supply low- grade ore which quite uniform analysis and structure from one end the Mesabi Range the other. The analysis close per cent iron and hard and dense. The iron oxide exists this rock minute grains and stringers small that the rock must crushed fine flour order free the iron oxide from the gangue. the rock crushed No. 100 mesh, per cent the ore can recovered concentrate having analysis per cent iron, per cent silica, and 0.03 per cent phosphorus. the rock crushed No. 200 mesh, per cent can recovered concen- trate having analysis per cent iron, per cent silica, and 0.02 per cent phosphorus. The iron-bearing minerals which this low-grade material contains are principally hematite, magnetite, and limonite, together with very small amount iron silicate. The finer the ore crushed, the better the extraction, the higher the iron and the lower the silica content the concentrate. Now consider what could done were necessary use this low-grade material the present state the art iron ore bene- ficiation and smelting. Obviously, the ore must mined, crushed very fine size, and the iron oxide must removed. This iron oxide, being too fine for blast furnace use, must agglomerated into coarse lumps. All this know how do, but were necessary, this time, for the blast furnace operators depend solely upon this material for the manufacture pig iron, their costs would neces- sarily increased materially due the increased cost producing the ore. other words, the end years, when the direct furnace ores are all ex- hausted, not know consider- ably more about mining, beneficiat- ing, and smelting methods than the present time, the price . 4 | pig iron certain increase unless are willing depend upon foreign supplies. Transition Poorer Ores Must Gradual reduce the cost smelting through the introduction any great rev- olutionary change the art iron making which will de- veloped point which will per- mit large tonnage produced annually. would take many years build such large industry based new and un- tried process even had the process completely worked out the laboratory. The physicists have been able bombard mole- cule iron oxide with stream electrons and produce pure iron without the use heat reduc- ing agents, but not even the great- est optimist would expect this tonnage basis within the next years. can, however, expect greater efficiency, cheaper power, and more efficient use existing heating and reducing agents. Cheap Gas May Lower Cost Utilizing Ores project already quite well worked out which produces cheap hydrogen from the North Dakota lignites. This gas may delivered pipe line the Minnesota iron mining districts, and may possible convert the iron oxide into metallic iron before shipment. Another project intended pro- duce both cheap hydrogen and oxy- gen the electrical dissociation water from power generated from the wind well along the experimental stages. These are examples the types improve- ments expected within the next years. the present type blast fur- nace continue use, the iron ore required the future must PPLICATION iron ore beneficiation blast furnace practice was dis- Davis, superintendent, Mines Experiment Station, Univer- sity Minnesota, before the recent Chicago convention the Western division the American Mining Con- gress. gave special at- tention the Mesabi Range because contains the greatest amount direct low-grade material. His pa- per published herewith abstract. have most the characteristics the ore used the present time. the fundamental principles upon which the blast furnace operates are unchanged, the gases must pass upward through the ore for its reduction and preheating. This means that the column ore must have structure which will permit large quantities gas pass through it. Changes Blast Furnace Design May Necessary Since most the concentrate which can produced from the low-grade ores will very fine, agglomeration large scale will required. Agglomeration ex- isting processes would increase materially the cost producing pig iron. This suggests the idea that changing the design the furnace suit the ore might cheaper than changing the struc- ture the ore suit the furnace. This has been done the copper smelting industry with great suc- cess, and some progress has been made along this same line the smelting fine iron ore concen- trate. Will Prolong Life Range For the beneficiation low- grade ores the processes are quite well worked out, and this operation cost with what known the present time. matter fact, this fine iron concentrate has al- ready been produced commercially from one variety low-grade ore total cost about $3.50 per ton, including mining, beneficiation, royalty, taxes and all other direct operating charges. obvious that costs are reduced materially, the saving must made mining, crushing and fine grinding, which costs total The mining cost $0.90, $0.30 per ton crude ore, can re- duced the use better drilling, blasting, and loading equipment. All the low-grade rock quite hard, and drilling and blasting are important items expense. Im- provements will undoubtedly made the field hard rock drilling. The crushing and grinding costs, amounting probably reduced quite definitely. The number work units actually con- sumed crushing ore compar- atively but since the ef- ficiency with which crushing done low, the total cost quite high. Explosive shattering be- ing investigated and new types crushing and grinding equipment are being developed. Definite re- duction may expected this cost. obvious that the future all taxes must increase and the face this increase, decrease can expected royalties. In- terest, overhead and other fixed charges will decreased because the necessary investments will lowered with the development simplified mining and beneficiating methods. However, the best that (CONTINUED PAGE 41) THE IRON AGE, November 14, 5 q § 4 ‘ | Unusual é HIS six-sided revolving drum, with Westinghouse motor mounted each face, was constant operation the Machine Tool Show Cleveland. The exhibit showed the operation motors all positions. balloon, though filled with gas, welded spherical container for natural gas. purpose maintain constant B.T.U. content and pressure all times. The sphere shown the illustration ft. diameter with steel walls approx- imately 5-16 in. This gas sewn together through 800 linear ft. welding done means two G.E. 400 ampere welders. Demonstrates HIS exhibit, stalled the Museum Science and Industry, Jackson Park, Chicago, demonstrates with simple equipment how wire drawn, woven into the strand and then finally twisted into the finished cable. Dra- matic photographic panels also illustrate various steps manufacture wire rope. IRON AGE, November 14, 1935 Large Spot Welder for Parts plane parts pneumatically operated spot welder, said the largest machine ever built for welding aluminum, brought out the Federal Machine Welder Co., Warren, Ohio. The first one this type has been in- stalled the plant the Boeing Co., for welding sections airplane wings and fuselage. The Boeing machine, here illus- trated, has throat depth in. and vertical opening in. has capacity for welding two pieces %-in. aluminum. 72-in. lower horizontal arm may sub- stituted for the 36-in. lower verti- cal arm, providing maximum opening in. The machine can supplied also with two 36-in. horizontal arms, giving maximum opening 8-in. The frame the machine fabricated steel. The front consists heavy copper face plate dressed off smooth finish and bolted the face the machine. The sec- welding aluminum alloy air- ondary transformer bolted this plate, which turn equipped with heavy gibs clamped place and holding the lower horizontal conductor position any prede- termined place the face plate. Speed production depends upon the gage, grade metal be- ing welded, shape the assembly and the time required handling parts welded. 1-in. diam- eter water-cooled electrode supplied lis, used. The air-operating cylinder ar- ranged that maximum pres- sure 1500 Ib. may applied the end the 72-in. arm. This air cylinder has cushioning device that the arms will stop smoothly the completion the upper stroke. adjusting screw oper- ated handle and provided with locking nut permits establishing the opening welding points from in. in. accessible latch- ing device permits the operator quickly release the stop the back the operating arm increase the distance between points from in. in. order clear ob- structions the work. The orig- inal length stroke restored removing the latch and permitting register. separate air-receiving cylin- der ample capacity supplied, and there reducing valve be- tween the receiving cylinder and the line permit supplying re- duced pressure the operating cylinder. The maximum air pres- sure delivered the line may in. Air control effected solenoid actuated valve controlled electric extension operated foot treadle. Welding Point Pressure Closely Adjustable Flexible copper conductors fab- ricated from rolled copper sheets 0.005 in. thick carry the current from the upper end the secon- dary the upper welding ‘point. They are located that the up- and-down movement will not have tendency crystallize break the flexible conductors. the top the upper arm locating de- vice carry weights, permitting predetermined weight pressure the extreme end the welding points case the welding opera- tion delicate requires very light pressure which cannot con- trolled sufficiently accurate the air cylinder. The air-actuated valve also con- trols electrical device which upon pressure the foot treadle causes the welding points, through (CONTINUED PAGE 76) THE IRON AGE, November 14, a be _ e Continuous Broaching V-8 Cylinder Heads VERTICAL ma- chine, constructed along standard lines employed the American Broach Ma- chine Co., Ann Arbor, Mich., il- lustrated below. vertical columns heavy ribbed section type are fitted with hardened and ground steel way caps and are equipped with cylinder having in- tegral slides. The table ing type, hexagon shape. The machine illustrated for broaching elongated holes alu- minum cylinder heads used V-8 motor assembly. The operation “push” broaching four holes time. The speed specified two complet