The Iron Age 1935-07-25: Vol 136 Iss 4

CHESTNUT AND STREETS, PHILADELPHIA, PA. Sales 239 WEST STREET NEW YORK, Owned, Published and Copyrighted CHILTON COMPANY (Incorporated) Executive and Publication Chestnut and Sts., Pa. MUSSELMAN, President FRITZ FRANK, Executive Vice-President FREDERIC STEVENS, Vice-President JOSEPH HILDRETH, GEORGE GRIFFITHS, EVERIT TERHUNE, ERNEST HASTINGS, WILLIAM BARBER, Treasurer JOHN BLAIR MOFFETT, Secretary FRITZ FRANK, President VAN DEVENTER Editor Managing News Editor Machinery Emeritus Washington Chicago Cleveland Detroit Boston Contents July 25, 1935 Perhaps Are Old New Methods Inspection Speed Output............ Heat Treating Different Parts................... Free Cutting Aluminum Industrial Propane for Bright Annealing............... Statistics Metal-Working Activity Construction and Equipment Buying.................. BAUR, General Advertising Manager DIX, Manager, Reader Service Member, Associated Business Papers Emerson Findley, 311 Union Bidg., Published every Thursday. Subscrip- Hottenstein, 802 Otis Chicago tion Price: United States and Pos- Peirce Lewis, Woodward Detroit 56th Sts.. Philadelphia. Pa. $12.00 year. Single copy, cents. W. B. Robinson. 428 Park Bidg.. Pittsburch Cable Address, ‘‘Ironage, Warren, Box 81, Hartford, Conn. Rycase—a high manganese steel. Note perfect case strongly supported with tough, ductile core. HOT ROLLED ALLOYS 2315, 2320, 2335, 2340, 2345, 2350, 3115, 3135, 3140, 4140, ete. Rycase (Het Rolled, machine straightened) Rytense A.A. (Het machine straightened) COLD DRAWN ALLOYS 2315, 2320, 2330, 3135, 3140, ete. HEAT TREATED ALLOYS (Het Rolled, machine straightened) Nikrome (Het Relled Drawn, machine straightened) STAINLESS AND HEAT RESISTING ALLOYS Allegheny Metal (Sheets, Welding Red, ete.) JOSEPH RYERSON SON, INC., Chicago, Milwaukee, St. Louis, Cincinnati, Detroit, Cleveland, Buffalo, Boston, Philadelphia, Jersey City COLD FINISHED STEELS Std. Shafting, Turned, Ground and Polished Special Aceuracy Steck Rycase High Manganese ete. TOOL STEELS Ryerson XXX, XX, Ryersen (Best for Dies) Chisel Steel Speed Mill reated Bars Diamenad High Speed Tool Holder Bits GENERAL STEEL PRODUCTS Bars, Structurals, Sheets, Shafting, Strip Welding Red, Tubes, Bolts, ete., are carried fer im- mediate shipment. 16—THE IRON AGE, July 25, 1935 TEELS purchased from Ryerson under all the different specifications can depended show unusually uniform response heat treatment. Uniform physical properties are assured. Ryerson manufacturing specifications are very exacting. Ryerson checking and inspection systems, together with the most modern warehousing methods, assure your get- ting uniform high quality steel that will exactly meet your requirements. Stocks include not only the standard S.A.E. analyses but also many special alloys developed meet particular requirements. You can depend the Ryerson Special Steel Division give you unbiased help with any prob- lems. Check with them and sure you have the best steel for your particular job. the Qu : | | | H THE IRON AGE ... JULY 25, 1935 ESTABLISHED 1855 Vol. 136, No. A\re Old Fashioned NCE while receive letter from man who takes exception our editorial treatment the so- called One these arrived last week and ac- cused being reactionary, out touch with the times and old fashioned. criti- cize the Administration your editorials," says the and the rest the paper you tell how good business Why are you not consistent and give the New Deal credit for saving business and making Now that's fair question. Certainly would rather ungracious for either busi- ness business paper condemn real benefactor. not nice bite the hand that feeds you. The point that believe that the present Administration, while undoubtedly has fed large number people with tax- money, has not fed business. the contrary, has given every indication trying starve death. And believe that the business gains that are now recording The Iron Age are primarily due the restoration confidence caused application Supreme Court check rein runaway horse that was headed, hell bent, toward the quicksands state social- ism worse. This opinion borne out, think, the fact that the upturn, distinctly contra-sea- sonal, occurred only after the sick chicken ate the blue eagle. Yes, perhaps are old fashioned. still believe hard work, thrift, coopera- tion between employer and employed and fulfilling promises that have been made. admire the old fashioned man whose word was good his bond. Speaking promises, wonder how many you recall the solemn promise which each new President makes his people be- fore permitted assume office? bit old fashioned too, perhaps, since dates back the horse and buggy days George Washington. solemnly swear that will faithfully execute the office President the United States and will, the best ability, preserve, protect and defend the Constitu- tion the United hope your committee will not per- mit doubts constitutionality, however reasonable, block the sug- legislation.” President House Ways and Means Committee connection with Cuffey ial Evolution Steel-Shapes Processing UTILIZATION com- bined pneumatic hy- draulic power pro- vided for the design new 14,000-ton steel extrusion press. The power generated what is, effect, air explosion. Its application has led the sci- entific possibility extruding and piercing ferrous metals directly into finished shapes from ingot billet plastic condition. For pur- poses this article such plastic condition can specified that heat-point which the metal when deformed will remain its deformed state allowed cool down from such heat-point. The extruding non-ferrous metals has long been accom- plished fact. Inability avoid de- structive die and tool contact with heated ferrous metals suf- ficiently lessen the duration contact has tended bar the ex- trusion process from practical ap- plication the field ferrous ac- tivity. However, some headway has been made, particularly for- eign countries, the utilization mechanical power within narrow limits. Such development has con- cerned, primarily, designing for IRON AGE, July 25, 1935 tremendous pressures without par- ticular relation high-speed move- ment. There have been difficulties sur- rounding the avoidance liberal patents, granted the mechanical powering equipment for extru- sion purposes. These equipments have included many devices engi- neered world-wide effort gain satisfactorily finished prod- ucts after the elimination inter- mediate processes. Owing com- mon thought pressure value rather than the value me- art, this case purely scientific, patent difficulties have seemed almost unsurmountable. The New Thought This condition was recognized Stanley Sparks, Norwalk, Conn., who reasoned that new ap- plication power principle developed would that getting ferrous metals, pierced and ex- truded lengths ft., away from and clear tools within allotted period time; the time permit destructive effects metal heat. visualized both means WAITE and the possible economic advan- tages through cost reduction. Experimentation and Results Over number experimental years his presentations and demon- strations have been along lines which have bordered, more less, “makeshift” because the ex- pense involved building new equipment. Even makeshift equip- ment has run into heavy expendi- tures. The operation such equipment has been carried nationally important plants and has brought about reasonable ac- complishment the production tubing and the smaller shapes diameters in. Single refined Reading wrought iron has been ex- truded in. from 6-in. round diameter. The extruded product has shown 12% per cent increase tensile strength and yield point. result such accomplish- ments negotiations are now under way, the patents in- vestigation ste. for licensing pro- duction within this range prominent maker steel shapes. There are also those, prominent within the industry, who believe | { 4 | | | 5 ° } | | | | | | | i | j 4 | } ~~ that the process has possibilities connection with extrusion tubing and rounds in. diame- ter and shapes like areas. The inventor, with apparent conserva- tism, places little credence ne- cessity for imposition diameter limits and fortified with samples, drawings and engineering checks basic theories well considerable experience ac- tual operation two equipments limited capacity and not bot- tle-power type described herein. Mr. Sparks has had wide experi- ence designer and builder mechanical equipment and con- versant with details its indus- trial use. president the Sim- plex Machine Tool Co., Cleveland, designed and built gun machines which were widely adopted. was vice-president and general manager the Lake Erie Machin- ery Supply Co., subsidiary the American Wire Co. organized and became president Cleveland Machinery Supply Co., Cleveland. Mr. Sparks’s initiation into the = 4) | the application extrusion power the original Sparks 2000-ton, single-cylinder, high-speed, double-acting, hydraulic tube extrusion press. this machine pumps accumulators were used for power generation. The diagram below illustrates the method substituting the explosive-like power herein described. VALVE EQUALIZING PIPE OPPOSITE PAIR BOTTLES CONTROL STATION PIPE OPPOSITE PAIR BOTTLES DISCHARGE BAR BEING EXTRUDED BEING CYLINDER DISCHARGE PIERCING TOOL TOOL FOR TUBES The lower diagram illustrates the type extrusion tool employed for tubes and shows the piercing tool and its position for tube operations. Note that the end the piercing tool supported the die and that the wall the tube formed the metal which passes between the die and the piercing tool. For ber solid extrusion the type extrusion tool employed illustrated the full diagram. bottles and cylinders, described but not shown, employed for returning the cross-heads and rams position. The chains the air bottle valves are for ease valve opening and closing during air charging operations. The cylinder operated, through pinion, gears and clutch, motor. cross-section (principal parts only) the proposed Sparks steel extrusion press. THE IRON AGE, July 25, Ave ZNO. field extrusion processing was 1914. His developments ex- truded shells were recognized and widely used during the World War. Since 1921 his work has pertained shapes and, during more recent years, has turned the high- speed movements which feature his new equipment layouts. His study this high-speed movement backed practical knowledge machines and mechanics. High-Speed Tool Clearing The time element tool contact with heat extruding and piercing and extruding ferrous metal shapes lengths even over ft., the inventor states, re- ducéd sec. under. The method accomplishment involves, diagrammatically illus- trated, valve-opening withdrawal water, which withdrawal pro- vides space for the creation air- expansion power. This power en- ram-speed movement with 20—THE IRON AGE, July 25, 1935 6500 water pressure, back four 56-in. diameter rams. The pressure developed explo- sive-like expansion air, which has been compressed bottle system bottles, water force, and held therein valves. The valves are, production opera- tions, electrically operated and con- trolled. 4 ABOVE thin wall illustration, reduction, high-speed steel tube extrusion. The second illustration Reading wrought iron tube. The material showed per cent increase strength and yield-point after ex- trusion. The third illustration reduction steel tube ex- trusion. The illustration the right extrusion, LEFT HIS die was used for 108 consecutive, high speed extrusion operations For effecting the operating, fully charged, condition air bottle the following routine followed: Initially, neither water air bot- tle contains water. The water pump started and fills the water bottle with water; this forces the air within the water bottle into the connected air bottle, effecting air pressure therein. This pressure then held the air bottle shut-off valve, chain operated, while the water bottle drained water, admitting, course, air. This newly admitted air then also forced into the air bottle water-pump pressure before and held there, increasing the pres- sure. This air compressing, water against air, repeated un- til the air bottle becomes fully charged with compressed air. Af- ter being thus compressed and con- fined, the air used over and over, there being avenue for its es- cape other than via confined water, valve controlled, the water bot- tle and under pump pressure, through which the air will not pass. case air bottles should used tandem, connections are made with the originally charged bottle. Otherwise the air bottle fully closed one end and has valve opening the other. The ulti- mate per-bottle air pressure against water contained water bottles is, cubical contents, seven times the cubical amount water. other words might take, theo- retically, seven drainings the water bottle originally charge the air bottle. charg- ing operation there will only that number drainings and including which the water pumps are sufficiently powered attain increased air pressure the air bottle. operation, water charge maintained four motor-driven water pumps 700 gal. per min. capacity. (There is, course, lee- way this specification.) These are constantly delivering water into the water-end the bottle system. The water bottles inter- vene between the pump and the air compression bottle. Air pumps, such, are neither required nor em- ployed. Split Second Timing the rams, water-end bottle-valve, electrically operated and controlled, opens and the escaping water power, explosively generated the confined air back it, di- rected against the heads rams and through compounded mecha- nism produces the extrusion stroke. The resulting ram movement is, obviously, high speed. These elements operation and move- ment are measured split seconds. The water power-movement straight line over distance but in., which said insuffi- cient enter the element fric- tion into its power application. Additional and smaller bottles and cylinders are used generate the power for returning the rams “shot” position. Water and air bottles are seamless and are tested (CONTINUED PAGE 78) — . | { | | | | | | The Chronolog connected with the gage used making the last inspection and thus shows visually all times the number pieces that have been produced and inspected. New Methods Inspection Speed NGENUITY reducing produc- tion cost probably not dis- played any greater extent any branch the metal-working industry than manufacturers small automobile parts. With large production and, best, nar- row margins profits per piece, manufacturers these parts con- stantly are spurred cut cost corners wherever possible. increase output, much more rapid inspection and almost com- plete elimination rejects, have been brought about the adop- tion the National Acme Co., PRENTISS Resident Cleveland Editor, The Age Cleveland, new methods in- specting small parts machined large production basis. This inspection procedure ap- plied the inspection front and rear housings end plates for starting motors, which are ma- chined under group bonus plan with special line equipment for progressive operations. The total earnings the employees the group, including four girl in- spectors, are based the number parts that are shipped. Under the new inspection set-up the fin- ished parts are not inspected the inspection stead, the housing department does its own inspecting and entirely independent the inspection de- partment. The responsibility for output rests entirely with the (CONTINUED PAGE 80) THE IRON AGE, July 25, ‘ ‘ | { > | | | > | | | | { ° | ° ° ° Ampco Metal forming dies. late years, and es- pecially with the ad- vent stainless steel for wide usage, the suitable alloys for use die work has been receiving increasing consideration. The fac- tors which have influenced this search for better materials are, part, the desire for longer life from dies, greater continuity op- eration, less maintenance, better work appearance, and reduction buffing and finishing costs. Various die steels and cast irons are service throughout the die shops the country. And varia- tions these steels and irons are introduced from time time. few instances cemented carbides are used for dies small work and very extensive runs. One the most unusual metals adaptable for general die service alloy produced Ampco Metal, Inc., Milwaukee, Wis. bronze the copper, aluminum, iron type, produced with as-cast hardnesses ranging 340 points Brinell hardness, measured under 3000- kg. load. Softer bronzes are, course, not suitable. And bronzes heat treated obtain the required hardness lack the strength and in- tergranular bond necessary withstand the extreme stresses en- countered. addition, Ampco Metal, this alloy called, contains intermetallic iron-aluminum com- pound which imparts superior wear resistance the alloy, denced the greatly increased life shown the softer grades gear, bearing, bushing, and weld- ing jaw service. This intermetallic compound consists very finely divided particles, which are in- tensely hard, and which, with the 22—THE IRON AGE, July 25, 1935 Stainless steel parts formed bronze dies. delta phase, carry the wear-re- sistant burden service. Since the beginning the ma- chine age, bronze has been recog- nized anti-friction metal, well suited for sliding contact with mat- ing steel surfaces. Logical, then, the inference that bronze hard enough and strong enough for the service would make excellent die material; and yet even hard- ness not the key, for while most Ampco Metal dies use have Brinell hardness slightly over 300 points, yet they outwear hard- ened nitrided steel dies 600 Brinell hardness over. The tensible reason for such perform- ance the smoother, easier action unlike metals contact. the first paragraph this article were mentioned factors which influenced the quest for more suitable die metals. Analysis Ampco Metal’s relation these factors may interest. First mentioned was the desire for longer life from dies. Users these bronze dies have advised that they almost invariably outwear steel dies due the fact that steel dies will gall and “load,” and the frequent necessary wear the steel dies out size much sooner than the Ampco. There are exceptions, course, but the average per cent the bronze dies render considerably longer life than steel cast iron. The second and third factors mentioned were the desire for greater continuity operation and fewer maintenance requirements. assembly general industrial plants where smooth operation several departments pendent, continuity operation forming, stamping, drawing one more the departments important factor. Further, but this same respect, reduction maintenance time and expense likewise important. The use non-galling dies distinct ad- vantage here. The bronze requires only from one-fifth one-twentieth | | | | } | | | Pa} i | much redressing steel, again because the fact that unlike metals running together not load pick and the surface the die remains smooth and clean. manufacturer, for instance, who cold-reducing 2%-in. pipe with 3/32-in. wall in. two operations, has advised that the steel dies previously used afforded 200 300 pieces before requiring redressing; the Ampco dies ser- vice present afford from 1500 3000 pieces before the die must cleaned up. Similarly, manu- Stainless steel tray and pan formed bronze dies. facturer drawing stainless steel bowls obtains 125 pieces from the copper-base die against pieces from the steel die between redress- ings. The fourth and fifth factors men- tioned being desired die ma- terials were better work appear- ance and reduction buffing and finishing costs. These factors are Ampco Metal, Inc., Milwaukee, Wis. confined certain types produc- tion, course, inasmuch finish many the parts now being fabri- cated. Stainless steel fabrication most cases involves good finished appearance, however, and the production stainless articles the die problem most acute. Here elimination buffing costs more important than life the dies, from the cost standpoint. Stainless, being tough metal, difficult form draw best. And any die material that will not only render longer life, but that will also resist loading galling, ideal. Be- cause this latter characteristic, Ampco Metal being used not only connection with stainless steel, but also with sterling silver, nickel silver, and aluminum. Due the absence die marks pieces formed, buffing costs can reduced from per cent per cent. Thus, not only are production and finishing costs low- ered, but better work produced, production “kinks” are great extent ironed out, and die costs themselves are reduced. Work .done copper-base dies includes the forming automobile frames, oil line pipe, refrigerator tops, bumper guards, stainless steel trim, pre-lacquered trays, au- tomobile fenders, zinc shells, hacksaw frames, wire shapes and plastics. Ampco dies are also being used for drawing washing machine tubs, sterling silver trays, German silver cups, tantalum wire, stainless steel beer barrels, gaso- line pump domes, automobile head- lamps, and for the swaging torque tubes. Dies are cast from either wood plaster paris patterns. casting close size, great deal machine work eliminated. heat treatment required, that deformation from high temperature contact. The hard grades Ampco (CONTINUED PAGE 78) Ampco Metal dies cast. They require very little tooling before being placed service. THE IRON AGE, July 25, 1935—23 ° ° ° plant called upon heat- treat thousand more different metal classify and simplify the many heat-treating processes involved, commensurate with the physical characteristics required. This in- cludes standardizing mini- mum variety steels and alloys minimum number heat treat- ments. With this then possible erect heat- treating division with the least and variety furnaces and equipment and greatly de- crease the size the personnel. Company Makes 115 Different Types Machines With this view the Interna- tional Business Machines Corpn., the world’s largest maker busi- ness and office machines, recently rebuilt and reequipped its heat treating division its plant makes 115 different classes ma- chines and its plant includes buildings with combined floor space 575,000 sq. ft. and em- ploys 3500 workmen. Its ma- chines are characterized tricacy, large number parts, precision operation, long life and indispensability modern of- fice work. Some these machines combine more separate ac- counting functions. The Alphabet Subtraction Accounting Machine 24—THE IRON AGE, July 25, 1935 reating 1000 has 50,000 separate pieces consist- ing 2400 different parts and contains miles wire connec- tions. the construction these ma- chines, strength materials paramount, and for wearing parts the required physicals can ob- tained only heat treatment. This phase handled modern and completely equipped treating division recently signed and rebuilt. stated, thousand different parts pass through here, and simplification heat treatments has been accom- plished part selecting steels only five analyses for most the structural and working parts the machines. These five analy- ses are SAE 1010, 1020, 1112, 3115 and 3140. Depending upon the grade and requirements, these analyses are purchased the form hot-rolled and cold-drawn bar stock, forgings cold-rolled strip. addition these Nor- way iron, nickel alloy magnetic AKING more than one hundred different classes machines, the Inter- national Business Machines Corpn. has the problem heat-treating fully one thou- sand separate wearing parts. For the sake simplification most the structural and working parts machines are confined five analyses iron and silicon iron are used ex- tensively for magnet cores and armatures. The desired electrical properties are obtained final annealing treatment parts have been completely ma- chined. Beryllium copper, the new alloy copper which under proper heat treatment develops hardness com- parable with tempered spring steel, LEFT bottom furnace, showing loaded car and system firing. RIGHT Row naces. | | | | | i val Different Parts steel. Beryllium copper also being used for various electrical contact parts. Standardization materials has been accompanied standardization heat- treating operations, which was made possible recon- struction and reequipment the treating division. and electrical conductivity equal better than that brass and bronze, also being used appreciable amounts for various electrical contact parts. The heat treatment for each part specified the blueprint and listed the operation record which accompanies each manufac- turing lot process. The manu- facturing lots received the heat-treating department are de- livered one three sections: carburizing and annealing, case hardening, the tool and die sec- tion. Gas fuel has recently re- ° ° NEALEY American Gas Association placed fuel oil, and there are gas-fired furnaces and seven elec- tric furnaces the department. Carburizing and Annealing Section Three box-type furnaces are employed the carburizing and annealing section. These are gas- fired and are equipped with auto- matic temperature controls the potentiometer type, operating and off motor valves the air lines. The air supplied all the furnaces from one big blower one pound pressure. The gas dropped from line atmospheric pressure and inspirated the burner the air, the ratio the two being exactly controlled automatic proportioning device. The temperature control valve cut into the air line only. Five recording and controlling pyrome- ters are mounted metal dust- proof cases the The furnaces are all insulated fire brick construction, incased steel plates and provided with coun- terweight doors. The first furnace has hearth size ft. and overfired with four velocity-type nozzle-mixing gas burners. The second furnace has hearth ft. and underfired two gas burners, one each end. The third furnace approximately the same hearth size has six gas burn- ers, three each side, underfiring the hearth with the hot products combustion rising around both sides into the heating cham- ber. Steel plate aprons are used loading and unloading, and like- wise steel forks mounted small wheels are em- ployed large parts, carburizing boxes, Small quench tanks are conveniently placed for hardening. Carburizing these furnaces accomplished packing the steel parts with solid carburizer al- loy heat-resisting boxes and hold- ing the charge carburizing heat hr., depending upon whether case depth 0.010 in., 0.015 in., 0.020 in. over required. Hardening practice varies accordance with requirements, quenching direct from the box cooling the box and later reheating and quenching 1450 deg. electric vertical retort- type furnace for carburizing with city gas also used for small parts which cannot packed con- veniently boxes with solid car- burizers. This furnace equipped with fan provide forced cir- culation the carburizing gases. This furnace also used for an- nealing parts and alloy nickel mag- netic iron parts. Either copper plating anti- carburizing paint employed for parts which require selective car- burizing and hardening, for in- stance gears and cams which re- quire soft hub permit taper pinning assem- bly, rivets which require soft tenon ends per- mit easy riveting assembly. This section the heat-treating department equipped also with car botton fur- nace. This has doors front and rear and track running through for the cars operate on. The ear hearths are and THE IRON AGE, July 25, it | | there are two cars that one can loaded while the other the furnace. Heat supplied through gas burners, eight side, and these eight are divided into three large ones over-firing and five small ones under-firing the work. The car hearths are heat- resisting cast alloy iron sections resting refractory piers the car top and the lower burners fire between these piers. This furnace used chiefly for the annealing cast iron relieve casting strains and improve machinabil- ity, and for the annealing Nor- way iron obtain proper electrical properties. order prevent sur- face oxidation, the Norway iron parts are packed with cast iron chips in- heat-resisting alloy iron boxes suitable size. Case Hardening Section The case hardening section con- tains seven standard pot furnaces ft. diameter, ft. high and hooded with induced draft for fume removal. Cyanide other com- mercial salts having similar case hardening effects are used these pot furnaces. The pots are in., and each furnace heated with two three gas burners the type already described, firing tangentially the pots and lo- cated close the top the fur- naces. The waste products com- bustion are vented near the bot- tom. Each furnace built in. firebrick and in. insu- lation and incased steel shell. provided with auto- matic temperature control like that used the other furnaces. Pot life these gas-fired furnaces considerably more than that pre- viously obtained other types furnaces. pot life 7500 heat hours not unusual. front the pot furnaces are three rectangular steel quench tanks for oil and two circular ones for water. These are served with chain hoists and steel baskets op- 26—THE IRON AGE, July 25, 1935 mer, erating back and forth over- head rail. Above these tanks system pipe coils, 3-in. pipes with 1%-in. pipes inside. The oil pumped through the larger pipes and cooled cold water circu- lated through the smaller ones. control beard contains seven indi- cating and controlling Gears, cams, screws and small parts SAE 1010 and 3115 steel are case hardened here quench- ing 1500-1550 deg. When heated for min. case depth ABOVE MALL formed from beryllium copper. Parts made material combine fatique resistance, cor- 800 rosion resistance conductivity. uctivity 600 RIGHT 400 EMPERATURE ranges the fabrication and heat treatment beryllium cop- per. 0.003-0.005 in. acquired; min., 0.006-0.008 in.; and min., 0.010- 0.012 in. Some these parts are drawn temperature 450 deg. These cases are too thin give accurate Rockwell scale reading, but the hardness equiv- alent file hardness. For the hardening high-speed steel, two oven-type electric fur- naces equipped with gas curtains the door openings are used. The gas curtain provides the necessary atmospheric control within the furnace and prevents the oxidation Hot working range and scaling parts. The high- speed steel preheat furnace the resistance wire type for tem- peratures 1850 deg. The final high heat furnace the Globar type for temperatures 2500 deg. box-type furnace underfired with four gas burners above mentioned electric preheat furnace are used also for harden- ing stainless steel, carbon steel, blanking and shaving dies high-carbon high-chromium There are three pot furnaces one which neutral salt used for hardening high-carbon steel parts. These are heated with two gas burners each. Three nitrate baths, each fired with single gas burner, are available for temper- ing and blueing. Beryllium copper, the new cop- per base alloy, which, under prop- treatment, develops great hard- ness and electrical conductivity range Annealing range Heat treating range equal better than that brass and bronze, finding wide- spread application for various elec- trical contact parts. Parts made from beryllium copper, analyzing beryllium, 2.00-2.25 nickel, 0.25-0.50 per cent; iron, 0.10 per cent maximum, and the bal- ance, copper, are heated 530 deg. for periods approximately hr. hr., depending upon the ultimate hardness and physical properties desired, and also the amount cold working the parts (CONTINUED PAGE 82) — cr co | | | 7 | 180 Liquid A 1400 1300 1200 1000 900 800 600 500 400 | Screw Machine Now important characteristic good machining metal its ability discard scrap quickly. clean-cutting material not only does not impede the cut- ting tool, but assures more accu- rate cut. addition, tools retain their sharpness longer because larger entrant angles may used without diminishing the quality the surface finish. Long shavings are not only an- noying, but they also retard oper- ation. This particularly true metal machined automatic screw machines, the speed which makes “free cutting” absolutely essential. This term coined denote the rapid breaking cut scrap that falls away from the machined piece, leaving the metal surface clean and not cluttered for the on-coming tool. Aluminum, because the devel- opment certain alloys, has now been added the list metals which the trade terms “free cut- ting.” understand the diffi- culties which preceded this devel- opment, may well sum the conditions which brought about serviceable free-cutting metals. The first the free-cutting metals developed was leaded brass screw machine rod, contain- ing about per cent copper, per cent lead, and the remainder material which has met the requirements free cutting well that has been little degree responsible for the present state the modern screw machine. High-sulphur, low-carbon, cold- drawn steel, although much more free cutting than ordinary low- carbon steel, not nearly satis- factory from the standpoint ma- chineability free-cutting brass. LUMINUM, because the development certain alloys, has now been added the list metals termed least two alloys, one with magnesium and one without, two tempers, are now available. The data this article were supplied the Aluminum Co. America. Many materials, not particularly adaptable for high-speed screw machine production, are eminently satisfactory for general machining operations. Every new type metallic material almost imme- diately appraised its adapta- bility for machine produc- tion. Culmination Long Research Commercially pure aluminum not adaptable for general use automatic screw machines, high-strength, heat-treated alumi- num alloys have, considerable degree, the properties desirable for the production screw machine parts. even more free-cutting alumi- num alloy has long been needed, however, and development such material has been studied for number years. The success leaded brass screw machine rod in- terested aluminum research scien- tists, but whenever lead was added aluminum-copper alloys the experiments the result was failure. During some the was demonstrated that alloys sufficiently high copper per cent and above) machined fairly well, but these alloys could not commercially hot rolled rod be- cause hot shortness associated with the high-alloy content. The addition tin certain concentrations would impart free- cutting properties some the heat-treatable wrought alloys, but would impair their hot-work- ing characteristics that the eco- nomic production screw machine rod from them was impractical. Scientific thought returned time and again consideration the possibilities alloying lead and aluminum. the course an- other investigation occasion arose when molten aluminum was fluxed with various lead salts. Sub- sequent analysis indicated the presence lead such concen- tration that complete quantitative reduction the salt and solution the lead the liquid metal had taken place. preliminary test determine the free-cutting qualities the al- loys was made measuring tool wear and the power remove unit volume metal. examine the chip size and the finish lathe tool was used which would give long, continuous chips and rela- tively poor finish with most wrought aluminum alloys but the same time would give small, well broken-up chips and good finish with free-cutting brass. Such arbitrary method evalu- ation could not indicate quanti- tatively the performance ma- terial all the variety oper- ations screw machine, and THE IRON AGE, July 25, 1935—27 ii chip produced turning one the new free cutting aluminum alloys shown the lower view; that material with poor free cutting qualities shown above it. the new alloy subjected actual screw-machine operations. The simplified test proved accurate. material which gave fine, well-broken chips the test performed similarly the screw machine, although marginal alloys might show reversion long, stringly chips critical oper- ations. Subsequent measurements made means specially adapted Charpy impact machine, dyna- mometer tool the Boston type, and Croft’s sawing test, indicated that the chip size was much better criterion free-cutting properties than power tool wear measurements. Now that the production free- cutting aluminum alloys was actuality, was found that the concentration lead required for satisfactory machineability the commonly used strong alloys was too high for the practical produc- tion ingots uniform chemical composition. Multiplicity Elements Gives Better Machineability solution the problem con- sisted the discovery that the simultaneous presence small con- centrations multiplicity ele- ments was much more efficient 28—THE IRON AGE, July 25, 1935 producing satisfactory machine- ability than any one element alone. From number elements found satisfactory, lead and bis- muth were chosen supply the multiplicity because was further found that these elements had rela- tively small effect the other properties the alloy. The effect copper machineability was also kept mind, and its concen- tration was placed about the maximum for the satisfactory hot working large ingots. This, then, one number possible alloys having free-cutting qualities. the “T” temper, which the condition the metal after the application both solution and precipitation heat treatments, the tensile properties not differ greatly from those the duralu- min-type alloys free-cutting brass. But the “W” temper (solution heat treatment only) the alloy relatively soft material excellent machineability which can satisfactorily cold worked, while the wide range mechanical properties offers opportunities for broad application. Large Scale Production Studied With the laboratory tests suc- cessful the problem how fab- ricate this new alloy large-scale production had solved. But the problems alloying and cast- ing were overcome, and hot rolling and drawing presented great difficulty. Soon rod the new al- loy was available quantity lots the Edgewater, J., works Aluminum Co. America. Here was found that the alloy was much more free cutting than the aluminum alloys previously used, and work was initiated develop technique take advantage the potential economics offered. The relatively low yield strength the alloy the “W” temper offered the possibility cold-work- ing operations after machining, although the same time pre- sented the problem bending during machining. Deformation and breakage during machining Screw machine parts, and chips, produced from free cutting aluminum rod. | 3 } | | were overcome slight changes tool design. The “T” temper the alloy has the advantage higher yield and shear strengths, but somewhat lower impact resistance. The rela- tively low degree toughness ap- peared responsible for break- age during machining some set- ups. Careful. examination the alloy both tempers led the conclusion that alloy with toughness corresponding im- and the cutting properties the alloy the “W” temper would make desirable addition the free-cutting alloy field. was found that duralumin- type alloys, which develop their optimum properties aging room temperature, are generally tougher for the same tensile strength than alloys which are aged elevated temperatures. induce aging room temperature, magnesium was added the alu- minum-copper-lead-bismuth but this resulted the impairment the free-cutting properties the alloy. The alloy the “W” temper was found have prop- erties comparable those dura- lumin and free-cutting brass both strength and toughness. the “T” temper, involving aging slightly elevated temperatures following solution heat treat- ment, very high yield, tensile and shear strengths were obtained, although this was the expense some elongation and toughness. Two Alloys, Two Tempers, Now Available recapitulating may seen that there are now available least two alloys, one with mag- nesium content, one without, two tempers, that there choice four different materials. Considerable production ence has been accumulated the use all these materials. some applications, such manufacture counter-wheel, the free-cutting aluminum alloy rod has replaced free-cutting brass rod with change machine set-up, speeds, feeds tool angles. Tool wear free-cutting alumi- num alloys appears slightly higher than free-cutting brass, but much lower than that ob- tained with steel duralumin screw-machine stock. Although the development free-cutting aluminum alloys rep- resents step forward the his- tory screw-machine products, not assumed that they will displace all aluminum alloys previ- ously utilized. Art Museum Displays Stainless Steel Breakfast Set breakfast set, fabricated modern dining room displayed the Industrial Arts Exhibit the Metropolitan Museum Art, New York. The flatware and center tray are also made stainless steel. Because the pleasing appearance the set considerable attention has been directed the utility this metal material for modern design. Use stainless steel these articles was made possible through the cooperation Elec- tro Metallurgical Co., New York. , Po, THE IRON AGE, July 25, 1935—29 * q ° ° ° | Propane Used For Bright A\nnealing ROTARY ELECTRIC STEEL CO. playing important part the development De- troit steel-producing center. produces line round and drawn bars and rods standard analysis from in. in. diameter and steel strip widths from in. in. Most the company’s products are sold au- tomobile and parts manufacturers the Detroit district. One hundred per cent scrap steel being melted and cast the conventionai pouring method, al- though the plant also equipped cast the rotary method, which originated. this method scrap steel charged into electric furnaces, rapidly melted and poured into molds rotating high speed. Centrifugal force distrib- utes the steel the outside the mold, where cast circular bloom. Special Atmosphere Prepared Combustion-Type Controllers Emphasis placed accurate control all manufacturing proc- esses, especially the process bright annealing strip steel, which car-bottom annealing furnace the company’s own design. Coils strip are stacked bases, two bases each car, and covers light alloy construction placed over them and sealed around the bottom 30—THE IRON AGE, July 25, 1935 with sand. The annealing must done carefully controlled re- ducing atmosphere. Industrial propane used pre- pare the special atmosphere phere controllers. inexpensive mixture gases, suitable for many controlled-atmosphere furnace ap- plications, produced the par- tial combustion propane refractory tube filled with coarse refractory impregnated with The controllers can adjusted within limits give output gas having analysis most suitable for each individual ap- plication. The major constituent the mixture nitrogen, but hydrogen, carbon monoxide and carbon diox- ide are also present. The atmos- phere used the Rotary plant provided mixing and burning air and propane the ratio representative analysis the atmosphere shows the following: Per Cent Carbon dioxide 6.3 Oxygen 0.0 Carbon monoxide 8.00 The volume air required for complete combustion volume propane would 23.4. The low cost the product gas due the large amount nitrogen which added the air used for com- bustion. With industrial propane the ratio about making Philgas Department, Phillips Petroleum Co., Detroit the product gases cost about one- twentieth that the raw material. Positive accurate control the air-gas ratio over the entire range tor-driven air-gas mixer. The inflow can noted instantly, any time, glance the two visual flow meters the rotary type. Water vapor condensed tap water temperature and partly removed from the outgoing gas means surface cooler and trap. The remainder the moisture re- moved passing the gas through activated alumina dryers. com- pact drying unit installed, con- sisting two dryers parallel, one which being reactivated while the other drying service. Removal water vapor from the product gas this means complete that the dried gases have The product gas leaves the dryer approximately in. water col- umn, and enters distributing line from which smaller service lines take off numerous intervals with flexible, quick-coupling connections each annealing base. The inlet pipe which protrudes vertically from the each base. The gases circulate through the center the stack, down between the ontside the stack and the cover, and out through the sand seal, burning they emerge. Annealing pots are mounted cars with refractory bottoms, the | in | | | { { | | | as Pht | | | cars being moved forward every hour. The atmosphere gases are introduced the pots after they have been the furnace about hr. and have been brought temperature approximately 1400 ABOVE HARGING end annealing fur- nace. Industrial pro- pane used pre- pare the special at- mosphere com- bustion-type, fur- nace atmosphere controllers against wall). ° RIGHT annealing, the outside lay- slight deposit flocculent carbon which can easily blown off. Note that the third stack the outside coil has been removed, revealing the bright surface the rest the coil. 1500 deg. Each pot remains the furnace for about hr. The atmosphere gas continuously circulated through the annealing pots during this entire time and also during the cooling period after they emerge from the furnace. The appearance the strip after annealing completed shown one the illustrations. slight deposit flocculent car- bon noticeable the outside layer metal, which can easily blown off, leaving shiny, clean surface. the third stack the photograph, the outside coil strip has been removed, revealing the uniformly clean, bright surface the rest the coil. This product provides excellent surface for the application nickel, chromium other metallic plating, enamel paint, and insures longer life for the dies used making stamp- ings for which much the strip bought. Preparations are being made THE IRON AGE, July 25, ‘ the Rotary Electric plant ex- tend the use industrial propane through suitable burners for dry- ing the ladles and nozzles used pouring steel. Gas Stored Liquid Form Industrial propane gas belongs the series hydrocarbon gases commonly found natural gas. its normal state gas, but may compressed into liquid form and held such, under mod- erate pressure, concentrate ther- mal value and thus facilitate transportation and storage. pos- sesses all the inherent advantages natural gas industrial fuel, due its uniform composi- tion, high thermal value, and fa- vorable combustion characteristics. From the refinery producing plant, industrial propane shipped specially constructed tank trucks the user’s plant. kept liquid form storage, but used allowed vaporize and pass gas through piping into the build- ings the various gas-burning appliances. The gas pressure may re- duced through suitable automatic regulators the pressures most suitable for efficient operation each appliance being served. Thus may employed both high and low pressure and total premix, partial premix, systems the same plant, desired, without the use compressors. Any desired type automatic control can read- ily obtained through conven- tional thermostatic other control devices. This simplicity means that su- 32—THE IRON AGE, July 25, 1935 pervising, maintenance and operat- ing costs are extremely low. tank car normally contains ap- proximately 9600 gal. industrial propane; consequently minimum- sized installation for receiving tank car shipments should have storage capacity 15,000 gal., that when there sufficient space the plant tank accommodate another carload, there would still adequate reserve fuel for unin- terrupted operation for consider- able time. special tank trucks the Rotary Elec- tric plant, where stored the tank shown left. Kept liquid form storage, allowed vaporize used and pass gas through piping into the building the gas-burning appli- ances. Industrial propane being used dustrial heating processes, among them being hardening, drawing, normalizing, carburizing, cyanid- ing, metal melting, space heating, soldering, brazing, oxy-propane cutting, lithographing, tempering, forging, upsetting, melting, enam- eling, japanning, drying, internal combustion engine fuel, glass melt- ing, glass annealing, core baking and galvanizing. World Industrial Production Gaining ORLD industrial production continued advance during May, according the monthly statement economic conditions foreign countries issued the National Industrial Conference Board. Improvement was reported England, Canada, Australia, Ger- many, Italy, Belgium, Spain, Fin- land and several Central and South American countries. Condi- tions remained substantially un- changed, according preliminary reports, France and Switzer- land, while some recession occur- red the Netherlands, United States, and Mexico. Unemployment declined from April May according prelimi- nary reports, follows: Denmark, 22.0 per cent; Norway, 16.0 per cent; Germany, 9.6 France, 6.7 per cent; Italy, 6.0 per cent; Great Britain, 2.6 per cent. The number unemployed France estimated have de- clined additional 6.0 per cent during June. Unemployment the United States was 0.9 per cent higher May than April. World prices important raw materials averaged per cent high- during May than the preced- ing month and per cent higher than May, 1934. Prices wheat, sugar, cotton, rubber, silk, and tin advanced. Coffee prices continued decline. During June sharp rise wholesale prices occurred Italy and more moderate rise was reported Germany. French and English prices remained lower than the end May. . | | j } | } i | | | | bearing pads the motor block are rough finish broached one pass the rate one minute this special Oilgear hori- machine. Main Bearing Pads Packard Motor Block Broached Special Machine been installed the plant the Packard Motor Car Co., Detroit, connection with produc- tion the new eight-cylinder Pack- ard known the “One Twenty.” Main bearing pads the motor block are rough and finish broached one pass the rate one minute Oilgear special hori- zontal broaching machine. The block broached inve