The Iron Age 1939-08-03: Vol 144 Iss 5

FRITZ FRANK President VAN DEVENTER Editor Cc. E. WRIGHT J. A, ROWAN A. I, FINDLEY Managing Editor News Editor Editor Emeritus Machinery Editor Art Editor Metallurgical Editor Associate Editors Washington Editor Morretr Resident District Editors Pittsburgh Chicago Cleveland Detroit Editorial Correspondents London, England Cincinnati FRAZAR Boston Hamburg, Germany MEYER CHARLES Post Milwaukee San Franciseo SANDERSON ASA ROUNTREE, JR. Toronto, Ontario Birmingham Leroy ALLISON EDMONDS Newark, N. J. St. Louis TURNER, Ruffalo Owned and Published CHILTON COMPANY (Incorporated) Editorial and Publication Office Executive Offices Chestnut and 56th Sts., 239 West 39th St. Philadelphia, Pa. New York, N. Y. OFFICERS AND DIRECTORS A, MUSSELMAN, President FRITZ J. FRANK, Executive Vice-President FREDERIC C. STEVENS, Vice-President JOSEPH 8. HILDRETH, Vice-President GEORGE GRIFFITHS, Vice-President EVERIT TERHUNE, Vice-President WILLIAM BARBER, Treasurer JOHN BLAIR MOFFETT, Secretary JOHN VAN DEVENTER, JULIAN CHASE, THOMAS KANE, CHARLES BAUR, BAUR, General Advertising Manager DIX, Manager Reader Service Member, Audit Bureau of Circulations Member Associated Business Papers Indexed in the Industrial Arts Index. Published every Thursday. tion Price: United States and Pos- sessions, Mexico, Cuba, $6.00; Can- ada, $8.50; Foreign, $12.00 a year. Single copy, 25 cents. Cable Address, ADVERTISING STAFF Emerson Findley, 621 Union Bldg., Cleveland B. L. Herman, Chilton Bidg., Phila. H. K. Hottenstein, 1012 Otis Bidg.. Chicago H. E. Leonard, 2°39 W. 39th St.. New York Peirce Lewis, 7310 Woodward Ave., Detroit . H. Ober, 239 W. 39th St.. New York D. C. Warren, P. O. Box 81. Hartford, Conn. Don F. Harner, 1595 Pacifie Avenue, Long Beach, Cal. Contents AUGUST 1939 Drop Forgings Stainless Steel Throw Away the Scrap Barrel Manufacture Artillery Ammunition Steel Tile Stands What's New! Defects Non-Ferrous Ingots New Types Heat-Treating and Process Control Ap- Crankshaft Wear Compared the Assembly Line Washington News THE NEWS BRIEF Weekly Ingot Operating Rate Rate Activity Capital Goods Plant Expansion and Equipment Buying New Industrial Literature Products Advertised Index Advertisers Copyright 1939 Chilton Company 100 118 144 fe in- unit, over Ltd., con- nent. vood, 105 part- for and and azine 100,- ment ,000; 540,- , has jlens- * lathe para- ) for that date ment, gaso- com- Cal. chine -story reigh- : You Wouldn’t Intentionally Handicap Skilled Hands often hard determine from cost sheets exactly how much the unseen qualities steel the production your skilled shop men. bars not machine uniformly, hard spots break dull tools, bars are too hard for bending and forming, alloy steel parts must re-treated secure desired physical properties—then costs, down profits. This one the reasons why Ryerson has spent years building stocks better, more uniform steels—steels worthy the Ryerson seal Certification. All Ryerson certified carbon steels are made rigid that assure the most desirable qualities each particular type steel. Ryerson Principal products stock for Im- mediate Shipment include—Bars, Structurals, Plates, Iron and Steel Sheets, Tubing, Shafting, Strip Steel, Alloy Steels, Tool Steels, Stainless, Babbitt, Welding Rod, etc. 28—THE IRON AGE, August 1939 certified alloys are from selected heats which the hardening factors (analysis, grain size, are within narrow range that assures uniform heat treatment response. With every shipment, large small, Ryerson sends accurate data the chemical and physical properties the alloy bars furnished. This added service given without additional cost obligation. When you need steel that responds skilled hands and keeps production flowing smoothly specify Ryerson Certified Steels. Stocks are complete and immediate shipment assured. Joseph Ryerson Son, Inc. Plants at: Chicago, Milwaukee, St. Louis, Cincinnati, Detroit, Cleveland, Buffalo, Boston, Philadelphia, Jersey an 2 ESTABLISHED 1855 AUGUST 1939 Vol. 144, No. LOT SWEAT MERICAN Federation Investors, Chicago, has just completed study taxes paid during 1938 representative American cor- porations. presents some interesting findings about other things well taxes. For example, these companies have more than million stockholders, compared with some 2.8 million employees. Stockholders, therefore, out- number employees more than two one. Average number shares held per stockholder 104, and more than three-quarters the stockholders have not more than shares each. Two thoughts spring automatically from the above findings. One that the owners our great American are not plutocrats but are people comparatively modest means. The other thought that, labor entitled voice public affairs proportion its numerical strength, stockhold- ers might justly claim heard the same grounds. Taxes paid these corporations, according the Federation, amounted average $2.73 per share common stock, whereas the average dividend paid per share amounted $1.33 less than one-half much. This, turn, gives rise thought why investment private funds has been reduced volume during the past Prospective investors must face the fact that the tax collector who does the taking out will benefit from profits twice much the investor who does the putting calculating the tax bill paid these companies the payroll basis, was found that amounted average $576 per wage earner. This turn gives rise vision invisible man standing back every three workers and exacting full year's pay $1728 from their pay envelopes. The invisible man, course, the government employee whose wages are paid taxes. And taxes, Mr. Roosevelt aptly said when Governor New York State, paid the sweat every man who There lot sweat thousand million dollars. And, roughly, this was the 1938 tax bill the 163 concerns surveyed. poh | | Z d + on nis | 0; 4 Ciki You Men Save “It’s refreshing, job like mine, find men who really study problems —who contribute much toward solving them. You Inland men work like members our own staff—always the alert for ways improve our quality reduce our costs. find that the time spend with Inland sales representatives, metallurgists and executives time spent the advantage our good many steel buyers feel that way—and will good many more, when they discover the real meaning and value Inland Service. SHEETS STRIP TIN PLATE BARS PLATES FLOOR PLATES STRUCTURALS PILING RAILS TRACK ACCESSORIES REINFORCING BARS 7 ‘ 1 | 7 | ‘ production drop forgings from stainless alloys, those alloys which might more suitably termed corrosion and heat resisting metals, longer considered pre- senting difficult forging problem the plants having all operations under the supervision competent metal- lurgical staff. quite true that the manufacture drop forgings from these alloys represents specialized the forging industry, where experience and sound knowledge metallurgical principles and unusual degree skill are each considerably more than average im- portance. Due the greater toughness these metals within their forging tem- perature ranges, their closer limits forging reduction, their sistance flow the dies, and their reaction cold working, punching and trimming, number problems are themselves the fabrication the ordinary alloys and carbon steels. The effect the rate cooling, together with the correct principles heat treatment necessary produce de- physical properties and corrosion are characteristics under- — — ~ \\ \ }} | | —_— ~ if i} j Wil i Waka ‘ weet o THOMPSON Sales Engineer, Transue Williams Steel Forging Corp. stood only the technically trained engineer. The ability the drop forger improve the physical properties these corrosion resisting alloys through proper working refinement creased the demand for this class product tremendously. These forgings, because their ability resist cor- rosion and withstand high tempera- tures and pressures, have enlarged the field forging application. The valve industry has found the use forgings from these alloys in- dispensable meeting the demands the trade for valves give guaranteed service such industries refineries, power plants and paper mills. Pressure governors and regulators, pump shafts, pistons, airplane motor starters, weld- ing and cutting torch heads and nu- merous items marine equipment have unusual records attesting the advantages these newer metals. Their stainless qualities have also de- veloped many forging parts for use the food, dairy and packing industries where the safeguard public health national importance. Stainless steel not single alloy, but rather entire family alloys, which there are three main branches groups: The martensitic steels, the ferritic steels, and austenitic steels. The martensitic steels composed mainly chromium, iron and carbon, are magnetic, afid can hardened and tempered heat treatment much the same manner ordinary steels, excepting that they will harden intensely when cooled air from the higher temperatures. The most com- mon steel this class used drop forging identified type No. 410 and contains 0.12 per cent maximum carbon with chromium range 13% per This analysis sometimes modified the addition columbium, aluminum molybdenum for specific purposes. The ferritic steels, which have chromium content per cent and over with carbon under 0.15 per cent, are not hardenable heat treatment and therefore are only annealed for purposes machineability secure better corrosion resistance. this condition forgings this steel are relatively strong and have good duc- tility and are used where extreme hardness not necessary and more corrosion resistance desired than can secured the martensitic types. the third group austenitic type, composed chiefly chromium, nickel and iron, the predominating forging type most commonly specified No. 304, per cent chromium, per cent nickel, with maximum carbon content 0.08 per cent. Two other much used types this classification are No. 302 and 303. The former THE IRON AGE, August a rae i yi 5 | i | x G BA : the same type 304 with the excep- tion that the carbon range 0.08 0.20 per cent and the latter, which known free machining grade, usually alloyed with small percentages molybdenum, selenium, zirconium, copper sulphur. Also worthy mention this group are the reverse 18-8 alloys, those with per cent nickel and per cent chromium, due the demand for forgings this steel the chemical industries. This analysis, classified type No. 325, used both with and without the addi- tion copper. These steels are non- magnetic and cannot hardened heat treatment, able hardness possible cold working. the annealed condition they are relatively stiff but extremely ductile. the corrosion resisting family metals considerable attention should also given the high nickel alloys which Monel metal, Monel, and nickel have developed ularly increasing demand their use forging parts. Monel metal which non-ferrous nickel-copper alloy has been used for drop forgings for long time and due its success diversified applications the newer types, Monel and “Z” nickel which are capable heat treatment, have been developed increase their scope combining corrosion with greater strength and wear resist- ance. “K” Monel and “Z” nickel like Monel will harden mechanical working, and therefore this feature sometimes taken advantage com- bining certain amount work hardening with thermal treatment secure exceptional The selection either these metals should based mainly the mechan- ical requirements necessary for the particular application, inasmuch they have the same general corrosion 32—THE IRON AGE, August 1939 resisting qualities. Brinell hardness values 286 drop forgings Monel and 340 “Z” nickel with good depth penetration are pos- sible after proper heat treatment. With some work hardening these limits can readily increased 321 and 375 Brinell respectively provided the proper temper material used. These alloys are readily forgeable and practically any forging design produced from ordinary steel can suc- cessfully made these metals the necessary precautions and edge correct heating procedure and temperature ranges are observed. Wastage Must Low Drop forgings the steels and al- loys briefly outlined the foregoing, carefully supervised during all opera- tions. Due the higher cost these metals, wastage excess flash and ex- cessive scrap loss must eliminated. secure economies this phase production well insure the ad- vantages the inherent qualities the metal, the bars billets should heated automatically controlled semi-muffle furnace. steels bar sizes larger than in. diameter should preheated 1500 deg. 1600 deg. F., allowing ample throughout, and then transferred high temperature furnace maintained 2150 deg. 2200 deg. Forging should begin just soon the steel reaches the furnace temperature. The above temperatures are reduced for the higher carbon steels. Excessive temperature and prolonged heating high temperatures produce growth which likely cause rup- ture the steel during forging. The steels, 18-8 types, bar billet sizes used for drop forging not require preheat- ing, but are found work best when charged directly into the maintained temperature 2100 deg. 2200 deg. The steel should heated quickly and forging oper- ations begun just soon the steel heated throughout. The per cent nickel-8 per cent chrome type usually forged little lower temper- ature, generally beginning about 2100 deg. The heating operations prior forging Monel metal, Monel and “Z” nickel are somewhat more critical than those for the aforementioned stainless steels. Care must taken avoid the metal being exposed sul- phurous heating atmospheres other sources sulphur, and should charged into hot furnace which reducing atmosphere maintained, The furnace may operated 2200 deg. 2250 deg. but the bars must removed while their temperature still rising, usually when they reach 2000 deg. 2175 deg. account the increased strength and stiffness the corrosion resisting alloys forging temperatures, about per cent more blows and some cases larger equipment than for producing the same part ordinary steel. Inasmuch this stiff- ness increases the temperature drops, often necessary reheat and again bring the metal rapidly the forging temperature for com- pletion the part. The first few blows start the metal flowing and minimize the danger rupture splitting. Dies should designed that the metal placed nearly possible the blocking impressions match the contour the finishing im- pression avoid incompletely filled forgings well checks and cold shuts. These metals cannot forced out easily into the flash gutters the dies the carbon steels and there- fore great care must taken relieve crowding punching out cen- the metal wherever possible other forging designs. The limit effective deformation for the straight chromium steels may considered 1650 deg. F., cepting the per cent chromium irons which should worked about 1400 deg. for the proper refinement. The forging reduction the chro- mium nickel steels may conducted until the steel cools about 1750 deg: before reheating, unless high cal properties are desired. forging continued below this | ] | | ( | | é | |—Partially completed hammer-upset forging which has ruptured. n el Ww pl the reduction should small avoid rupturing the part. Forging operations Monel, Monel and nickel should dis- continued metal has dropped between 1700 deg. and 1850 deg. depending upon the type and the de- sign being forged. may said that the temperatures detrimental these alloys are considerably below those necessary promote good die life and very seldom would forging reduction attempted these minimum tem- peratures. trimming the flashings from drop forgings stainless alloys at- tention should given the temper- ature which this operation takes place and likewise the amount semi- cold working which the forgings have been subjected. Generally for production quantities the decision whether hot cold trimming should used dependent upon the size and design the forging. However, cold trimmed, annealing operation should given beforehand. The straight-chromium steels with air hardening characteristics trim- med hot should conducted tem- perature 1750 deg. 1800 deg. permitted cool much lower they pass into the critical range and hardening will take place. Occa- sionally forgings certain shapes will tear open the flash line when hot trimmed. This condition can usually remedied permitting the forging cool slightly, which causes the flashing harden enough give more shearing effect the steel. Edged With Stellite the austenitic nickel-chromium steels conditions this nature are not encountered and difficulties trim- ming occur unless the forgings have been subjected give satisfactory service life the dies, punches and broaches should edged with stellite, the Wear these tools, particularly the punches and broaches, makes cult maintain good cutting edge. Due the fact that large number the applications for these alloys re- quire the development high physical grain fibers unbroken con- tinuity the forgings are essential. stainless steels have directional Properties the same common steels, grain flow condition can also duplicated these types. The microstructure stainless steel for drop forging particularly the forging operations FIG. Unetched steel showing the unsatisfactory distribution sulphides which results poor (right), the same steel etched with glyceregia. Both photos are upset nature. Forging bars that are subjected severe de- formation such header hammer upset operations require steel with exceptionally good surface finish and with chemical elements the proper proportion. The value this cannot over-emphasized the forging bars are the free-machining type, demonstrated the accompanying photographs. Fig. shows partially completed hammer-upset forging which ruptured due improper ratio carbon, sulphur and chromium combined with the distribution sulphide inclusions. The photomicrograph, left, Fig. FIG. Unetched steel showing sulphide distri- bution permitting successful upsetting; (right), the same steel etched with glyceregia. Both photos are shown shows the amount and distribution the sulphide inclusions this steel which, conjunction with its analy- sis, provided insufficient ductility withstand the upsetting operation. Fig. (right) shows this same steel etched with glyceregia. That there very little free ferrite ap- parent contrast with the illustration the right Fig. The appreciable differences microstructure between this heat and one which forged satis- factorily can understood com- parison with the photomicrographs Fig. The chemical variation the two heats, which largely responsible for gh ig ne re WS ize / : in m- re- their structural difference, shown comparing the unsatisfactory which has carbon content 0.12, 12.70 and 0.50 per cent with the forgeable heat, shown Fig. hav- ing carbon content 0.075, 0.35, 0.014, 0.16, 0.32, 13.33 and 0.54 per cent. stainless steels this nature are withstand the severe stresses which they are subjected upset- ting operations, their chemistry must controlled with carbon and sulphur not over 0.10 per cent and 0.20 per cent respectively and the chromium content the upper limits the specification. order secure the best results after heat treating, both respect Brinell hardness and corrosion resist- ance, the mium steels should contain specified amount carbon and chromium. doing the higher hardness values can obtained necessary, and drawing temperatures avoided which decrease the ability the steel resist corrosion. Tempering draw- ing heats the neighborhood 900 deg. 1100 deg. lower the impact values and lessen the resistance cor- rosion. combination per cent chro- mium and 0.10 per cent carbon will harden approximately 360 Brinell after oil quenching, and with carbon 0.35 per cent, not uncommon obtain hardness over 500 Brinell. the chromium content increases, the effectiveness the carbon hardening strengths high 200,000 per sq. in. are possible these steels after heat treatment. mium austenitic steels can annealed maximum softness air cooling quenching from temperatures above 1900 deg. They are readily ma- chineable after this treatment, and the treatment produces Brinell hard- ness 135 179. Monel metal not responsive 34—THE IRON AGE, August 1939 thermal treatment for the development hardness. annealed for the purpose further continuance cold working facilitate other op- erations which may required sub- sequent forging. open box annealing may used. The tem- peratures for open annealing are between 1650 deg. and 1800 deg. and for box annealing the range 1350 deg. 1450 deg. most satisfactory. order secure the maximum hardness Monel forgings, the forging work should continued the lower forging temperature limits with light blows, after which further working the metal again neces- sary 1200 deg. The amount working this temperature basis for the final after the thermal treatment. Forgings which have Brinell 241 after this working can treated Brinell temperature 1100 deg. F., followed furnace cooling the rate about deg. per hr. following this procedure the machining oper- ations would conducted after the working treatment and before the age- ing operation. heretofore, “Z” nickel properly hardened and supplemented cold working will produce unusu- ally high physical properties with very good hardness values for metal with such exceptional corrosive resistance. order accomplish sufficient cold working assist securing maxi- mum hardness, the forgings should first quenched from furnace with atmospheric control temperature 1950 deg. 2000 deg. F., and then necessary intermediate anneals 1350 deg. 1750 deg. may given. However, the final anneal must the quench anneal from slightly above 1950 deg. water order place the metal condition for the precipitation hardening. The hard- ening temperature should closely controlled, being held tem- perature 920 deg. 930 deg. for Since all machining operations ex. cepting the light final cuts grinding must done before hardening, recommended that the hardening done reducing furnace atmos- phere from which the parts may either furnace cooled removed and water quenched. discoloration the machined surfaces not objec- tionable, the atmospheric control the hardening furnace not However, very important that reducing atmosphere maintained for the quench annealing operation and also that the forgings held heat longer than necessary heat them throughout. The selection the proper type corrosion resisting alloy for any spe- cial application should considered with the utmost care. Thorough knowledge all conditions en- countered the service life the forgings, such temperature, pres- sure, and corrosive media, individually suggested that the correct type alloy recommended one the special- ized engineers from the mill who familiar with the analysis required for each special condition. the applica- tion unusual nature might found advisable conduct several service tests various alloys check the suitability certain materials duplicating similar conditions the laboratory. However, will rarely found that the research laboratories the mills producing these alloys cannot give immediate advice regard- ing all details type metal use, its limitations, and complete fabricat- ing instructions. The development new applica- tions all branches industry for these newer metals constantly in- creasing. More efficiency and longer service life are being demanded equipment and transportation manu- facturers which make mandatory that drop forgings, properly designed and engineered throughout all stages fabrication, are used accomplish the satisfactory fulfillment purpose. | | | | i | | of i ( \ OLD drawing steel precision operation. And the making dies for cold drawing requires even more precise technique. Too frequently costly dies end the scrap faults hold this, the first section two-part article, the writer reviews his years experience and ad- vances suggestions spare most dies the ignominy the scrap barrel and accelerate shop output. cold drawing department many mills may lack the glamor and appeal some the highly publicized departments that intrique the uninitiated. However, all too fre- quently this department may well worth looking into regards costs and profits. many, cold drawing battle royal—and just long steel mills insist upon tonnage basis for all departmental operations this picture will remain unaltered. For the time being, this tonnage mania may ignored and the cold drawing shop examined some detail merely matter curiosity. First attract attention the large volume the small amount and generally dilap- idated condition the equipment used. many shops this condition Were corrected the department could raised the degree that its importance warrants. Then, conscientious effort and .attractive the large number manufac- who today make use this product, could shown that the use cold drawn steel they can only turn out better product, but reduced cost. The writer MOHT firmly believes the results would not only interesting, but surprisingly so. Just watch hard, cold steel, drawn the magic the die makers’ art into complex shapes—shapes that will utilized the manufacture widely diversified products, ranging from electric razors plows, from outboard motors battleships—should result realization how impor- tant part this cold drawn steel plays the daily lives everyone. should enjoy constantly expanding market. steel great value instantly transformed into cold having definite shape, size and charac- ter and value that disclaims any relation its parent. Then and there, the conviction born that tonnage has rightful place the picture. This particular department not only precision production, but job individual problem re- quiring expert planning and execution. product this department, there- fore, should considered basis. department constantly work- ing within limits thousandth part inch certainly should not classified department where 1/32 part inch the cause severe headaches. Seldom consideration given the fact that with steel cold drawn, the accumulation all mistakes (and the writer has learned from sad ex- perience that they are many and varied) from the hammer shop the annealing department are dumped non- chalantly the cold drawing depart- ment and there, regardless how seriously production affected, these mistakes are all too frequently ex- pected overcome. this point the die maker enters the picture. die maker without outstanding ability and initiative absolutely use cold drawing department. must familiar with every peculiar- ity the various steels drawing. must have working knowledge every department that affects his work any way. And, only for his own protection, must able make both Rockwell and Brinell THE IRON AGE, August ° ° ° hardness tests. Only with such background can become any value the department. Recently, the writer was cold drawing department which every- thing was running along its natural stride. But, suddenly, someone for apparent reason decided have “big Equipment was taxed its utmost, and everyone was uproar. during such exhibitions “efficiency” that the experienced die maker his ability, diplomacy, and often hard-boiled attitude con- trols production. must work pace entirely out keeping with the degree accuracy his work demands. must instantly recognize, before his dies are ruined, what each depart- ment did did not not cause delay the bar machines. must have the diplomacy induce the foreman some offending depart- ment correct, possible, whatever condition may responsible for de- lay. must maintain such atti- tude that will discourage the offending department from committing the same offence too often. Quite recently captain industry referred die makers necessary evil. Everyone privileged have opinion, but the attitude certain executives that die maker classi- fied non-productive seems some- what silly. the cold drawing steel the die bench not only the very heart production, but nine times out ten the brains The best proof occurred the late labor disturbance the steel mills had contend with. the mill em- ploying the writer, practically the first move made the opposing factions was attempt organize the die makers. Both factions arrived the same conclusion—that when die makers stopped, production stopped. The greatest detriment the pres- ent time the art cold drawing steel certain shops apparently the lack competent and experienced men placed position respon- sibility giving them absolute control over the department unit. Men this type should placed com- mand and invested with authority demand that steel brought into the cold drawing department such condition that will necessitate delay processing. Such men should consulted any and all things affecting the department. They should have enough knowledge the die making craft recognize good from poor work, and able issue in- structions the die gently, and not leave him depending 36—THE IRON AGE, August 1939 entirely upon his own Such foremen should all times realize that the incompetent die maker acts the writer suggested establishing set-up within the engineering depart- ment from which all technical data relative the making dies would issued. With that thought mind, six charts were shown founda- tion upon which such structure could built. such technical data from the engineering department are made available the foremen drawing departments, some the weird hap- penings which occur certain cold drawing shops could likely elimi- nated. example just such hap- pening, consider the following case (one several almost identical which the writer had considerable knowledge. The mill involved received order from one its customers specifying shipment cold drawn steel correspond identically with previous shipment. Simple enough! But, what actually happened? due time the or- der arrived the cold drawing depart- ment and steel was placed the floor ready draw. Nothing remained but place the die the bar machine and start pulling. Unfortunately there was die. There were blueprints data any kind available relative building die such was needed. one, including superintendent, three foremen, and six die makers— some whom had been connected with the mill years—knew anything about the job. The for this was that all this particular shape die work was handled one die maker, and was absent due sickness. Two thousand bars steel rested the floor and produc- tion stopped right that point. entire department ceased function because lacked the necessary data operate, data that should have been ested. diligent search the mill was made with the hope locating sample from the last run. The search was successful, but only cer- tain point. Six samples were found, but two samples were alike. There was other alternative but ques- tion the customer. The customer for- warded not only so-necessary sample, but for good measure attached tering letter referring delayed ship- ments. this time the whole organ- ization was aroused, and die finally was made. Ten days later the first steel was shipped, and the end two weeks the order was completed. Now, all further business this one- time customer handled com- petitor. This incident did not take place years ago, but recently. And can happen again tomorrow IG. 0.500 in. hexagon die the center-bearing type. Bars may drawn from either side. in. for the conditions that created the difficulty have not been altered. steel mill operations the easiest way erasing mistakes, generally speaking, utilizing the facilities the melting floor. the cold draw- ing department there one other re- course, that design and tion dies sound principle, sturdy enough overcome some the reasonable demands placed upon them. There are two types dies general use—the solid die and the so-called built-up sectional die. has definite place the industry with distinctly separate function form, and the common practice ignoring this fact substituting one for the other all too disaster. This fact becomes more ap- parent these dies are compared Consider first the solid dies, their outside diameter and thickness. The sizes shown Table have proved | | p = n Sd ° iz the ally re- ruc- un- eral per- one vites later their The in. 2—Holder for 0.500 in. hexagon die the center- bearing type. Dies 0.650 in. may used with this ample strength withstand the tremendous strains which they are subjected. Figs. and 0.500 in. hexagon die and holder are shown, which properly made are capable drawing many thousands feet steel. hexagon used example, but the same applies shapes cold drawn. The hexagon merely the most predominating, and, furthermore, has common with all other shape dies the same faults and heir the same troubles. The die shown inexpensive make and the experienced die maker holder. offers great difficulty its con- struction. But, let the inexperienced die maker attempt build and place this die production and immediately finds himself more trouble than were try holding hatfull hor- The nets. This type solid die far the writer knows, was never used cold drawing shapes until was introduced few years ago. The “throat” radius, the radial center bear- ing sizepoint, and the fact that bars may drawn from either face, are all features which were adopted after ex- tensive experiments. claim originality made placing the die 3—This type die most commonly used. The size point located nearer one face, and not uncommon have section the die face break away. ~ nest holder. This was frankly copied from the automatic screw ma- chine thread-die holder. The dies smaller diameter were adopted after tests had proved was just waste steel continuing make these dies the 6-in. die- blank—hence, the holder. deal production over long period time has proved conclusively that sizes 0.650 in. this type die, with the proper care while produc- tion and having bars processed correct- for cold drawing, capable draw- ing high 50,000 ft. heat-treated steel Brinell hardness range 262 302 before losing size. Hundreds these dies have been built the sizes mentioned, and not more than Simple arithmetic alone reveals that such die cost quite low, particularly when compared with costs formances other dies frequently used for the same type work. Fig. shown the type die which was supplanted adopting center-bearing dies one shop with which the writer was connected. Here again the reference all shapes dies, and not hexagon dies alone. will noted that the bearing, size-point, adjacent nearly so, face and extending backwards face the opening increases without any definite regard for size, throat angle. This one fact alone, may work against this type die, will seen. Fig. the size point located the strongest part the die-blank, equal distance from either face. Fig. this size point located almost the weakest point the die-blank. not unusual when drawing bars through this type die have large section the die face break away. this occurs while drawing bars large diameter, becomes none too healthy the vicinity the bar machine. Fig. note that the radius approach throat approximately the same from each face the die. This feature allows the die re- versed need be, due ring form- ing, for any other cause which does not directly affect the size point the die. Right here one the best features this type construction. reversing the die, not only its life measurably increased, but often, for replacement, there avoided tie-up the bar machine which would necessitate discontinuing the job until new die constructed. the die involved complicated, some time may elapse before new one can THE IRON AGE, August ly. of her ~ £4. \) a: built. obvious that whatever reason necessitated reversing the die Fig. the same condition would force the removal the die Fig. from production. All bars, both standard and odd shapes, having sharp corners exert tremendous pressure die. And after die has been subjected this pressure for some time, will rule develop cracked corners. Many production runs have showed that the die Fig. can not compare with the die Fig. resisting corner cracking. These tests have indicated that drawing the same lot steel, when the die shown Fig. develops die having this same structural failure while the other die would test perfect. Various grades steel were subjected the same test, with the same results. There are various reasons, due other conditions, that will cause cracked dies. But these tests were made under conditions that were ideal possible. All dies used cold drawing steel regardless their hardness the steel from which they are constructed will due time develop ring. This ring forms the throat the die directly back the bearing and caused the tremendous pressure exerted the bar the point con- TABLE Recommended Sizes Solid Dies Diameter Hole Die Die-Blank 0.905 1.500 in. in. 1.775 2.500 in. in. Outside Diameter Thickness Die-Blank in. Plate dies con- in. tained holder in. in. in. in. cracked corners which are not due some bar condition, the cause due structural failure the die steel im- mediately surrounding the bearing surfaces; whereas, the cracked cor- ners the die shown Fig. may caused lack support surround- ing the bearing surfaces. fact, the writer has never seen type die Fig. remain competitive produc- tion with type die Fig. long enough develop structural failure. Repeated laboratory tests made the writer show this condition result- ing cracked corners is, rule, caused failure the steel; the failure starts immediately below the bearing surface and extends some cases deep in. Two die blanks were cut off the same bar stock and etched, both before and after punching, and they proved free from any fault. After the dies were made-up and hardened, both the same Brinell figure, they were again tested and proving satisfac- tory were placed production the same lot steel. due time one die would perhaps develop cracked corners, while the other die would remain production until removed due natural wear. Another test would show the cracked 38—THE IRON AGE, August 1939 tact with the die throat. The pressure this point will cause depression form varying depth and width ac- cording the amount draft the bar, its hardness, the condition the coating the bar, the hardness the die itself, and the lubricant used. The ring its first stage isn’t seri- ous, but will eventually reach point that demands attention. The ring ‘the principal reason for scratched bars caused the die, and being com- mon all dies the ring becomes one the die makers most serious prob- lems. The experienced die maker confronted this trouble will first examine the die and ring has developed will remove it, before at- tempting any further diagnosis the cause scratched bars. re- moving the ring the problem almost invariably solved. The size general innocent appearance the ring should never used basis forming judgment the amount damage can cause. Very frequently endeavor maintain production with ringed die, attempt made “nurse the die with disastrous results. All too often the bar ripped beyond redemption and the die ren- dered fit only for the scrap barrel. After few such attempts, the die maker should convinced that there only one safe course follow regard ringed dies—and that remove the ring. shape-dies where the ring must stone, each individual die maker erally has favorite method his own, which swears by. One old time die maker remembered with deep respect for was one those rare geniuses sometimes found the die bench who always seems the right thing the right time. The die involved was 0.250 in. ordinary octagon semi-soft die for drawing brass, and was badly ringed. novice would seem like hopeless task even attempt remove the ring and not remove any stock from the bearing, size point. The old timer took his file and said, “Look, here you file and here.” Quickly going over the eight sides the shape, fixed the die just good were new, saying “see, goot die you make chust like that.” many dies have filed before one finished “chust like that.” Ed. Note:—Next week the author will describe the making center- bearing die, and will discuss the evils “try out”, troubles due kinky cracked corners, Very Small Stamped From Bronze counted among the world’s tiniest fabricated products, was cently turned out the Wrought Washer Mfg. Co., Milwaukee. These washers, stamped phosphor bronze exceedingly close tolerances, measure 0.069 0.041 0.005 in. the accompanying illustration, they magnified times. would the combined area over 700 these minute washers cover the top silver dollar. quarter million them would weigh less than The Wrought Washer Mfg. Co. has recently installed special facilities fot producing washers and stampings very small size, requiring great cision. | | | | tic the eal pal Na lar the tile Uni Size } for Tap Lieut. Col army indeed fortunately situated with respect the po- tential supply brass cartridge cases during time emergency. This country blessed with prac- tically unlimited supply copper, and there are many very large brass mills, with extensive manufacturing Practically all these com- panies have adequate press and fur- nace equipment for the production large quantities cartridge cases. cartridge case for the: purpose holding the propelling charge powder, and for obturating, preventing the flow gas pro- the firing the powder charge, toward the breech the gun. Obviously, the objective have the propulsive effect the charge upon the base the projectile, secured the open end the case means crimping. Such known “fixed ammuni- tion,” that is, one which the projec- tile and cartridge case form single Fixed ammunition used from the caliber 0.30 rifle in- diameter shell. Anything than that becomes too heavy for easy handling the gun crew firing, some instances, cartridge cases are employed for carrying the powder charge, but not have the projectile crimped thereto. These cases are mainly used for large caliber howitzers mortars. the base all car- tridge cases pressed screwed primer, which used for the purpose igniting the propelling charge smokeless powder within the cartridge case. The primer must have PREVIOUS article, the June issue, described the equip- ment and technique necessary for the efficient production forged steel artillery shells. Herein, the equipment and procedure recommended for the manufacture brass cartridge cases are set forth detail. The author ammunition department, Frankford Arsenal, Philadelphia, and this ar- ticle released for publication the Chief Ordnance the United States Army. Statements and opin- ions are understood indi- vidual expressions the author and not those the Ordnance Depart- ment. accurate fit within the boss the case prevent the escape gases. Even slight leaks around the primer cause very material loss muzzle velocity, with consequent loss range the projectile. Fig. shows assembled primer and its parts. primer device used for igniting the propelling charge smokeless powder carried within the case. just mentioned, inserted and pressed firmly into place the reamed primer hole the base the case. The finish the reamed hole and the exterior part the primer head must very accurate and very fine finish. This necessary prevent the gas generated under high pressure within the cartridge case escaping the rear. Even very slight escape has marked effect upon the velocity, and consequently the range, the pro- jectile fired from the gun. addi- tion this, the hot gases, per- mitted escape, very rapidly erode the primer seat and the whole case rendered useless. must remem- bered that pressures often excess 34,000 Ib. per sq. in. are being dealt with, and the gas extremely high temperature. Referring again Fig. there THE IRON AGE, August ere his old the old oing you ithor nter- evils orld’s rhe These these has ies for ngs seen from left right complete primer, sectionalized head assembly, the battery cup, the firing plug, the primer cup, the anvil, and the body. The operation the primer quite simple. The firing pin the gun forces the firing plug downward against the primer cup. The percussion element contained within the primer cup pinched between the rounded portion the firing plug and the anvil. This pinching, which, effect, merely sharp blow, causes the percussion ele- charge carried the This, turn, ignited and flashes outward through the holes the body into the propelling charge within the cartridge case. This flame very in- tense and causes almost instan- taneous burning the smokeless powder propelling charge. give some idea the enormous forces generated within the gun, in- terest know that requires some- thing less than 0.008 sec. for the shell travel from breech muzzle, and that many projectiles attain muzzle velocity 2800 ft. per sec., and even higher. The manufacture primer requires accuracy, course, but with the great screw machine ca- pacity available, should present but small problem for time war. There are automatic combination in- spection and assembly machines for assembling the parts within the primer head. The capacity these machines per 8-hr. day very large, and their design such that they may readily duplicated time emergency. 40—THE IRON AGE, August 1939 The case must soft enough ex- ‘pand outwardly against the walls the powder chamber prevent es- cape gas toward the breech block the gun. Equally, must not hard result cracking split- ting. manufacturing operations these attributes are means careful and exact annealing and the correct design and clear- ances the drawing dies. Within the past year, the cartridge case shop the Frankford Arsenal has been with modern, high-speed, hydraulic presses and machine tools used manufacturing operations later described. Just for steel shells, the Arsenal not equipped for mass production, but the equipment does offer small laboratory produc- tion line employing the latest and best methods known the art. Drawings are available punches and dies, and working and inspection gages, whith represent the various cases produced from day day. manufacturers who may called for mass production may this small setup with great saving time required reach Procurement Brass Disk the series operations required case for medium caliber shell. facture all cases falls same general routine. technique appear only between number draws. Referring the various stages the may seen. The disk, the cup, seven draws, the trims, the the tapering, and the machined are shown. The brass disk procured commercial sources and standard composition being upon pro- ridge the the ig. the head ridge brass, per cent copper and per cent zinc. The size this particular disk 9.500 in. in. diam- eter, 0.800 in. in. thick, with weight 17% The disks are pur- chased annealed and are carefully in- spected for surface made imperfect disk, the flaws are carried forward manufacture and there results either rejected case case very short life. the Frankford Arsenal, large num- ber different caliber cases are manufactured; therefore, the pur- chase equipment presses with large range tonnage may economically used have been specified. other words, funds did not permit the buying press limited its size operation. Ob- viously, however, any firm entering upon mass production equipment more closely adapted the single size cartridge case which the company may making. Manufacturing Operations The first operation that cup- ping, which performed 350-ton capacity crank press. The actual oper- ation requires 250 tons pressure. Enormous strains have been set 3—Cartridge within the metal, which are now re- moved thorough furnace anneal 1148 deg. for time 125 min. The annealing furnaces with auto- matic controls are shown Fig. After the anneal, the work cooled means heavy, finely divided spray tap water, which gives excellent grain structure. The scale removed per cent sulphuric acid pickle. The cup then thoroughly washed and rinsed remove all traces acid, prevent future season crack- ing. The cup again returned the press line and given its first draw. hydraulic press, see Fig. The work- ing load required 190 tons. During this operation the length the cup increased from 2.25 in. wall height 3.25 in., and the thickness the lip the cup reduced from 0.702 in. 0.556 in. strain reliev- ing anneal the same temperature 1148 deg. again given. The same pickle and wash follow. Fig. shows ideal grain structure which has been found most suitable maintain the metal during manufacture. Then there follow six additional draws with anneal, pickle and wash after each. The movement stock, the displacement metal, is, inso- far practicable, divided between these draws, give the best metallo- graphic structure for long case life service. the end the seventh and last draw, the length the cup has increased from 2.25 in. length in., and the thickness the lip has been reduced from 0.702 in. 0.043 in. After the fifth draw the open end the case trimmed for approximate length two inches, and again after the seventh draw. the manufacture cartridge case where such deep drawing metal en- gaged in, the most highly stressed metal found the mouth the case. order that this metal will not become part our finished case, have purposely used more metal the original disk than actually required, leave stock for dis- card trimming. Heading the Case The closed end the cylinder has been formed with quite heavy sec- tion metal, provide for heading the case. this meant flattening the base and providing flange for the extractor the gun engage, order that the case may ejected after firing. form this head cold requires very large tonnage pres- cases are annealed furnace this type. THE IRON AGE, August itt Mie 3 a FIG. press for form- ing cartridge cases. sure, and for this purpose dial feed 2000-ton hydraulic heading used. This press has very high out- put per hour and has given uniform- accurate and satisfactory standard work. During the heading opera- tion, heavy boss also formed the inside the center the case. This boss for the purpose sup- porting the primer. The boss is, course, drilled and very accurately reamed close tolerances. the de- sign the heading dies, the metal the prime