The Iron Age 1939-07-06: Vol 144 Iss 1

JUL 6, 3 | al q ‘ : q ications, ated FRITZ FRANK President J. H. VAN DEVENTER Editor Managing Editor News Editor Editor Emeritus Machinery Editor Art Editor Metallurgical Editor Associate Editors Washington Editor Resident District Editors Pittsburgh Chicago Cleveland Detroit Editorial Correspondents London, England Cincinnati FRAZAR Boston Hamburg, Germany MEYER CHARLES Post Milwaukee San Francisco SANDERSON ASA ROUNTREE, JR. Toronto, Ontario Birmingham LEROY ALLISON Roy EDMONDs Newark, N. J. St. Louis TURNER, JR. Buffalo Owned and Published CHILTON COMPANY (Incorporated) Editorial and Publication Office Executive Offices Chestnut and 56th Sts., 239 West 39th Philadelphia, Pa. New York, OFFICERS AND DIRECTORS Cc. A. MUSSELMAN, President FRITZ J. FRANK, Executive Vice-President STEVENS, Vice-President JOSEPH HILDRETH, Vice-President GEORGE GRIFFITHS, Vice-President EVERIT B. TERHUNE. Vice-President WILLIAM A. BARBER, Treasurer JOHN BLAIR MOFFETT, Secretary JOHN VAN JULIAN THOMAS KANE, CHARLES BAUR, BAUR, General Advertising Manager DIX, Manager Reader Service Member, Audit Bureau Circulations Member, Associated Business Papers Indexed in the Industrial Arts Index. Published every Thursday. Subscrip- tion Price: United States and Pos- sessions, Mexico, Cuba, ada, $8.50; Foreign, $12.00 Single copy, cents. Cable Address, ADVERTISING STAFF Emerson Findley, 621 Union Bidg., Cleveland B. L. Herman, Chilton Bldg., Phila. Hottenstein, 1012 Otis Chicago H. E. Leonard, 239 W. 39th St., New York Peirce Lewis, 7310 Woodward Ave., Detroit C. H. Ober, 239 W. 39th St.. New York D. C. Warren, P. O. Box $1. Hartford, Conn Contents JULY 1939 Hot Weather Thoughts Cold Drawn Steel Hardening-Drawing Axles Automatically Photometric Dust Determinations Efficient Heat Treating Cleaning Metals Centrifugal Casting Metals and Alloys Soft, Semi-Bright Nickel New Method Cold Forming Report ASTM Convention New Designs Spot and Arc Welding Apparatus Metals Used Extensively Interior New Ships the Assembly Line Washington News THE NEWS BRIEF Weekly Ingot Operating Rate Rate Activity Capital Goods Plant Expansion and Equipment Buying New Industrial Literature Just Between Two Products Advertised Index Advertisers Copyright 1939 by Chilton Company (inc.) The Ryerson “Vacation Without Worry” plan all thought delayed, slow un- certain steel deliveries. also gives you assurance against interrupted shop schedules, fabricating delays and increased production costs. All you need leave the vacation order, Ryerson when steel needed.” Emergency well regular requirements will promptly from Ryerson stocks Certified Quality Steels—steels selected for uniformity and desirable working qualities—in short, steels that save shop time, reduce spoilage and lower labor costs. sure the Ryerson Stock List handy buying reference, and let help you make yours real vacation without worry. Joseph Ryerson Son, Inc. Plants at: Chicago, Mil- waukee, St. Louis, Cincinnati, Detroit, Cleveland, Buffalo, Boston, Philadelphia, Jersey City. IRON AGE, July 1939 — ‘ | . + fj Wj, YY Yi... WY Yj — jf Yi fy » ... THE IRON AGE ESTABLISHED 1855 JULY 1939 Vol. 144, No. Hot Weather Thoughts OME one has estimated that several million dollars worth combustibles, including some structures accidentally set fire, smoke the Fourth July. This raises interesting speculation the resulting economic balance. The prod- ucts created labor and purchased peoples’ surplus funds have been destroyed. One can argue both sides the question. did not permit people spend their surplus funds for things burn the linings their coats and trousers, they might perhaps spend this extra cash for things that would burn the linings their stomachs. And either case, the people making these hazardous products have been provided with employment. That, course, the philosophy back made-work projects, such leaf raking. Also the philosophy back plowing under agricultural sur- pluses killing off pigs, although the latter seem less excusable from the work creating angle. measure this same thought also such events our World's Fairs, where much labor and thought are expended erecting beautiful displays and impres- sive buildings destined torn down after one two years use. course, one could not say that such projects were altogether non-liquidating, for they coax money out socks and into circulation. Also out corporate surpluses, judging the expe- rience some the exhibitors. Going the scale the extreme non-liquidating economic activity, might select war the outstanding example. Here, most the effort entire population may devoted for period several years making things that not only destroy but are destroyed themselves. And even nation that may have very little the way financial reserve can apparently support this sort business for extended periods. Perhaps this sort evidence that has built the strange new philosophy that the way prosperity through profligacy. course, the real answer that our machine economy has created and stored much wealth that can stand little non-productive splurging times, espe- cially has tonic effect the customers. But have hold within limits. The good old projects goods for more through honest and earnest work are still the backbone our economy and always will be. this were not true, ought make automobiles that would wear out six months and build time bombs into all our automatic refrigerators. | 7 7 follows Walking through the various departments Inland’s modern flat rolled steel plant, you would see stacks sheets here and there with green tickets attached. This color scheme has purpose. The green ticket order from the metallurgical department hold those sheets there for laboratory tests and inspection before further processing. The green ticket bears, addition brief data certain standard tests such Rockwell and Olsen, the customer’s SHEETS STRIP TIN PLATE BARS PLATES FLOOR PLATES your order through every department the STRUCTURALS Inland Plant name, order number and lift number. This identifying information permits the metallurgist trace every factor affecting the quality the sheets. Every care taken see that each customer gets exactly those qualities which will make the sheets most satisfactory and economical for his use. These green tickets used Inland’s metallurgical depart- ment save time and lower costs for Inland customers. PILING RAILS TRACK ACCESSORIES REINFORCING BARS 4 : ‘ | | | | | | : - | q i 7 South Dearborn Street, CHICAGO District Offices: DETROIT KANSAS CITY MILWA the tool and die-making indus- try, both the bench and executive capacities, the writer several years ago went work die maker one the steel mills specializing tool, high speed and alloy steels. leave up-to-date job-shop with the finest working equipment and encounter the disorganization the mill department was something shock. Much the equipment was almost primitive, there was lack working drawings charts any kind, and practically all work was performed the cut-and-try method. For example, perhaps the die maker had produce die draw hexa- gon bar 0.500 plus minus 0.002 and couldn’t find die. (And the writer means find, looking the floor, under the bench, almost any- where the room.) Perhaps die would filed about 0.010 in. under size, then sent the hardening room for proper treatment, and its return, polished out, then part the bar drawn for size. When the size the necessary stock re- moved from the die draw the size desired. ‘Quite system! And still being practiced today. The writer found difficult stand such system, system which un- reliable, wasteful and involves added risk spoiling die the die maker. While years ago such system may have been the height efficiency, hardly has place the craft today. Therefore, system some kind was undertaken whereby the die maker would know the size make die that would draw the type steel under consideration the size desired without any preliminary fussing around. Public libraries were searched for information without re- sult, nor was anything available from the publishers that would helpful. The result was that what looked like moderate task actually extended over period three years, involving con- siderable clerical work and numerous experiments with dies different de- signs. The three-year research brought pickling, and annealing departments that were unfortunate. One the most important facts established was that the sand-blast, annealing, pickling and coating departments must work harmony order produce results the cold drawing department. die maker living can produce die that will stand production with annealed showing brinell hardness almost hard that the die. Even Carboloy dies stand the abuse bars loaded with sand sharp particles shot from the sand blast which acts anything but lubricant die. Nothing will scratch tear both die and bar quicker than improperly coated stock. Still another important factor the choosing proper drawing lubri- cant. After tying all such loose ends to- gether into workable whole, the re- sults obtained were most gratifying But, the gratifying results indicated perhaps that there serious lack knowledge and information this im- portant art—and don’t let said that the successful cold drawing steels this type art! several cold drawing departments the author has seen, the departments have overhead thousands dollars annually wages, and use thousands dollars worth dies per year, but regardless these facts, they were allowed wallow around year after year like ship with broken rudder. The large volumes money men- tioned are not estimates. The writer the one shop already mentioned built 1152 dies one year, but there was reason earth why 400 dies wouldn’t have been more than ample —the 400 dies certainly would have taken care production over that one-year period. The company main- tained engineering department and mechanical laboratory from which all customers’ inquiries concerning the characteristics and peculiarities the various steels under given conditions THE IRON AGE, July a 2 ay. i ' q ak . q “| 7 7 350 | 0.005 3 Size bar, inches correction for dies draw 3.50 per cent nickel steel, heat treated, with brinell hardness 262 302. Fic. 2—Diameter correction for dies draw heat treated vanadium stee!, having brinell hardness 262 302. 0.014 0.012 Reduction die diameter, thousandths Size bar, inches “oh | 7 | 0.018 | | | | | | | | EM | | 0.016 | | | | | } | / c | | | | 0.012 0.012 Ss | q 0.004 c 0.012 0.009 S 0.006 0.005 0.005 c 0.003 40—THE IRON AGE, July 1939 Reduction were answered. was some lay-out But, not one the gentlemen those departments, who blandly offered advice and imparted could give data how many thou- sandths inch bar steel would swell being cold drawn. This lack data reflection the ability the engineers—rather, just another example how neglect has handicapped this important branch the steel making industry. Perhaps one these days certain steel makers will transfer some affec- tion from fancy continuous mills the cold drawing department, stitute some overhauling modern hardness, not only costly but hardly keeping with the advanced state the steel industry general. The entire responsibility placed upon the die maker—he has decide the type die use, the numbers and amount each draft reduce the steel the practical size for finish drawing, always keeping the hardness range mind. And some cases, the die maker must even advise the rolling mill shape and size necessary for the first pass. Upon the die judgment and ability pro- duce satisfactory sample may rest order running into thousands dollars. Therefore would not 0.014 0.010 L 0.007 0.006 9.002 Size bar, inches methods and equipment. 3—Diameter correc- might some sweet profits even though perhaps prices were reduced. The writer has seen specific jobs remelted many four times and completely processed four different times and still show profit. This leads definite belief that means proper production methods far larger profits are possible, even larger profits prices should undergo re- sulting downward revision and con- sumer There steel that can made and cold drawn, but what can cold drawn desired finish and hardness, from charts regardless shape The antiquated custom bringing job the die bench ‘with specifi- cations other than the size, desired tion for dies draw chrome molybdenum heat treated bars, having hard- ness 262/302 280/310. far more feasible place the respon- sibility where belongs, the engi- neering department? The die maker could thus left free concentrate turning out the most perfect die possible, which after all his proper job. With some the difficult shapes being cold drawn today the die maker has responsibility enough the mak- ing dies. While off-hand the sys- tem using the engineering depart- ment might appear both complicated and costly install and maintain, actually such not the case. All prog- ressive manufacturers the country base die cost working drawings. the only way the cost product can sensibly arrived at— its fundamental that can’t ig- nored. Any plant operating otherwise under present day competitive condi- tions skating thin ice. Any engineer die maker worthy the title who familiar with the characteristics the steels being worked can adopt the six charts pre- sented here cover about any steel plant will called upon cold 0.014 0.010 0.009 0.008 0.006 0.003 0.002 draw. The writer has charts drawing over different types and special mixes through solid dies, drawing both ard and special shapes. And, when the bars were properly processed before cold drawing every bar produced was within the limits desired. Further- more, using properly designed die conjunction with the charts, die room costs were quickly reduced. The department involved the one mill operated hr. day, employing steadily six die makers flats and shapes. Three these were con- stantly hexagon dies. This force was eventually reduced the use properly designed dies built the chart measurements; (the accuracy the charts made possible build dies far enough advance eliminate THE IRON AGE, July 5 4 = Se] wo 0.002 0.0( 0.008 bar, inches wo ter correction for dies draw non-corroding steels having brinell hardness 180 241. 5—Diame Fic inell hardness 190 220. having ing steels corrod Fic. 6—Diameter correction for dies draw non- July 1939 42—THE IRON AGE } 0.007 | | Size bar, inches Fic. 4—Diameter correction for dies draw S.A.E. low-carbon steel, having brinell hardness 160 220. | | | | | { | | | | | | | 0.002 0.002 Size any hold-up the bar machines due lack dies), until finally one man was turning out all the hexagon dies necessary for three shifts. This reduc- tion from three one man was made the face constantly increasing production, and when peak production was reached, two die makers and one assistant handled all the die work. Die room cost was substantially reduced, also was production cost. Where single bar machine previously might draw maximum 200 bars 0.750- in. stock one shift, point was reached where shift draw 600 bars, someone certainly wanted know why. Round bars higher. Savings like these simply cannot laughed off. The information and this article have been com- piled from carefully kept records the actual cold drawing thousands bars steel. They offer au- thentic picture what accomplished. the data are care- fully applied, there reason why lot guess work and trouble ‘cannot eliminated. The type dies, their design and construction, along with the different coatings found most practical for the various grades steel, will discussed later article. Probably the charts Fig. and proved the most valuable. These controlled the die sizes for drawing the heat-treated steels, that is, 3.5 per cent nickel, vanadium, and chrome- molybdenum. The charts proved their worth more than one occasion, when trouble was experienced hold- ing bars size and trying eliminate twist showing that the fault lay the processing the bars before they reached the drawing department and not the dies. steels were cold drawn size after heat treat and were held within hardness range from 214-262 262-302; and some cases, especially with chrome-molybdenum high Chrome-molybdenum was far the most difficult the three steels draw from the standpoint and die wear. comparison the three charts will readily show the sharp tendency this steel swell when cold draw- ing the larger sizes. The cent nickel was the most temperamen- tal the three—while would stay within the desired size range, there little assurance just what happen the die. The steel strain heat treating that would develop into decided twist the bar while drawing. This action die isn’t conducive long die life. Vana- dium, contrary expectations, proved far the most consistent the three. For downright cussedness nothing can equal steels. The only redeeming feature they have the fact that they are easy hold size. Any variation from the proper annealing and coating will make them practically impossible draw. charts for non-corroding steels are shown Fig. and One chart controls the die size for brinell hard- ness range from 180 241, the other, for lower carbon content steel with brinell hardness range 190 220; the two are very nearly alike, and one most cases will draw either steel. Both are, however, necessary when drawing bars 0.001-in. limit. The remaining chart, Fig. covers wide variety steels the lower brinell hardness range, the steels. The charts, Fig. and will cover practically any steel that not heat treated, including high speed when using small draft. All these charts are based 0.025 draft. the cold drawing high speed steel has been found more practical use smaller drafts rang- ing from 0.008 0.015 in. most cases, depending the shape being drawn, order avoid strain checks. Charts shown Fig. and have proved accurate the drawing high speed steel when using heavier draft. all the charts the right-hand column figures designate the num- ber thousandths inch smaller the die should made draw given size, while the horizontal the various bar sizes. For per cent nickel heat treated bar in., the chart Fig. shows that necessary have die in. smaller than the finish bar in. diameter. When drawing S.A.E. steels after they have been heat treated, the chart Fig. should used. For 3.5 per cent nickel, vanad- hasn't been heat treated and the lower brinell hardness range, the charts Fig. and may used. using 4t little discretion and basing choice charts the brinell hardness the steel drawn, their wide range will soon become apparent. The importance having the vari- properly processed before finish cold drawing has been stressed herem. watching tons steel roll merrily their way back the melt-floor the scrap barrel route, the writer convinced that there short cut cold-drawing steel. One high speed shape the writer’s mill recently had, necessitated three break-downs with anneal after each one before finish drawing. Han- dled this way, the job was fool-proof. Then some one acquired the inspir- ation eliminating the anneal after the last break-down save with the result that every bar was rejected for strain cracks from the finish draw. Two bar-machine operators were laid off for two weeks, but the responsible genius sailed merrily on. Another case was S.A.E. type steel, heat This was hexagon bar with brinell hardness 241 286, normally easy job. The order called for hot-rolled steel, but due exceptionally poor surface was nec- essary cold draw for finish. keep the cost low possible was given just water-lime coat (which view the poor surface condition was just asking for trouble) instead the proper treatment. The first bars ruined dies, all them new. After the job lay the floor for three weeks, was finally decided handle should have been done originally. The result was that one die drew the remaining 275 bars and could have drawn 600 more need be. The two illustrations cited are not just the annoyances that crop from time time demonstrate that long distance must travelled before at- taining perfection, but certain shops are common-place, every-day rences that far nullifying the expenditure thousands dollars for modern equipment other depart- All too little attention has been paid this final precision production product before passes into the hands. weren't for the natural pride every true die maker takes turning out perfect work and the advice and counsel some the old-time steel makers helping him reach that goal, the writer that there would but cold-drawn steel ever get past the in- spection bench. Practically all worth while contributions made the art have come from the die bench. Year year, thousands dollars are spent for new equipment the vari- ous departments endeavoring make them more efficient, but unfortunately the poor little cold-drawing orphan all too often all too many mills contin- ues wear the same dress she has worn for the last years THE IRON AGE, July ; ‘< rear axle shaft subjected sudden shock more than any other part automobile and perhaps the one item which only recently received the considerable at- tention deserves. However, plants all over the country have, the last few years, directed much effort toward developing and perfecting new axle steels and methods processing. known that under certain con- ditions hard, tough steel will the job more efficiently than the same steel the as-rolled as-forged condition. also com monly known that poor job heat treating worse than heat treating all. The surface the axle must sufficient hardness guarantee long wear and yet the shaft itself must torsional impact and abnormal strain. This can accomplished only ap- - ace: Ww are shown here being discharged from the draw furnace. Photo the Surface Combustion Corp. plying the proper heat treatment selected high grade steel. Recently the Warner Automotive Parts Division the Borg-Warner Corp., manufacturer replacement axles and other parts, was iaced with the problem installing equipment for hardening and drawing rear axles. The desire was have equipment automatic every respect, not only constant heat maintenance but also mechanical handling, eliminate the human element and its variations regard all technical operations. The equipment also had universal take care more than one hundre different axles, ranging from large flanged type truck smaller stock car types, mechan ically handled automatic, con- tinuous furnace. Since all axles are machined before heat treating, was imperative also POWELL Chief Metallurgist, Warner Automotive arts, Borg-Warner Corp. have atmosphere furnace eliminate both scale and de- carburization. The equipment, installed unit which the axles pass through the hardening furnace, then through the quench and wash, finally through the draw furnace. The com- plete hardening and drawing cycle takes approximately hr. axles are never handled the oper- ator after once admitted the harden- ing furnace. The hardening furnace heated number gas-fired horizontal radi- ant tubes. Since the gas burned entirely within these tubes, im- possible for the products combustion come into contact with the work and cause decarburization. However, atmosphere air, were allowed enter the furnace, would Q/ I, ] cause scaling and under con even decarburization exclude air from the non-oxidizing atmosphere main- tained within the furnace. This at- mosphere generated special unit which delivers gas which tree oxygen, dehydrated, uniform composition and containing abun- and decarburizing are prevented, and result the axles reach the quench clean and free from surface de- fects after machining. Perhaps the most interesting and feature the hardening fur- nace the mechanical conveying system. This consists (four screws) centrifugally cast alloy heat-resisting screws. Two rows axles are conveyed through the unit the same time. The two pairs screws are geared together through variable speed reducer and driven from common shaft. the axles reach the discharge end the hardening furnace, they fall short distance gravity onto mechanically operated lowerator. The lowerator rapidly carries the shafts point above the level the quench- ing medium, where they are deposited onto the quench chute support and roll for short distance into the quenching oil and onto the quench tank convevor. The quench tank con- veyor carries the axles the quench tank into and through the wash tank and automatically deposits them upon the draw furnace conveyor. The draw furnace the recir- culated air convection type. Heating accomplished single large air heater mounted top the furnace. Heat from this unit carried and irom the (recirculated) suitable duct work and recirculating fan. Uniformity heat input con- trolled graduated valve pins both sides the furnace. Heating this furnace exceptionally uniform. The maximum variation hardness the drawn axles five points Rock- well. The conveyor the draw furnace consists four steel chains which return beneath the furnace. The complete over-all length the hardening furnace, quench tanks, and draw furnace approximately ft. The unit has capacity 700 per hr., equivalent 1500 stock car axles per 24-hr. day. symbolic mod- ern heat treating practice and straight line production. Results are indicative what great extent metallurgy has been incorporated productive plan ning. Photometric Dust Determinations ETAILED study and use photometric method termining the amount dust the West Virginia State Department Health. This method said rapid (readings can made few accurate, and consistent Its results. apparatus used about one- fourth the size standard micro- scope box, and consists constant tor the container holding the suspen- light-proof chamber) and outside. The suspension may im- pinger collected samples, the washings irom the electrostatic precipitator, from other apparatus for collecting dust. The constant light ob- tained controlling the voltage the current supplied tungsten filament lamp. The light directed vertically through the suspension the photoelectric cell. Readings show variations due settling the dust. There are numerous possible appli- sion, the cations and some limitations this Sample Reading per c.c., Estimated Number Particles Number from Calibration Count Curve 950,000 1,160,000 0.82 102 650,000 760,000 0.86 112 180,000 224,000 2,980,000 3,040,000 0.98 10,650,000 10,000,000 1.07 7,920,000 7,000,000 1.13 4,400,000 4,000,000 1.10 16.5 10,500,000 1.00 1,900,000 2,160,000 0.88 4,150,000 4,030,000 1.03 900,000 760,000 1.18 108 380,000 384,000 0.99 Note: Samples are impinger samples collected from dust chamber. Samples impinger collected from the brick plant. IRON AGE, July 1939 apparatus will probably find its great- est usefulness control instrument for use industrial establishments. Calibrations must made for each dust type dust plant using the equipment. many plants only one two calibrations are necessary. These calibrations can any person familiar with dust count- ing, that plant engineers, indus- trial hygiene consultants, industrial hygiene bureaus. The accompanying table shows re- sults with dust brick plant. First, calibration curve for the dust from the brick plant was prepared plotting instrument readings against the number particles dust per suspension. The median size the dust was 1.15 microns After the calibration curve was prepared impinger samples dust were collected from experimental dust chamber and the brick plant from which the original dust was ob- The table shows readings for these samples, the num- ber particles per c.c. read from the curve, and the number particles per obtained counting, using the technique described Public Health Bulletin 217. The high accuracy this photometric method demon- strated these data. 4 7 | q f | | | HERE one the Leeds Northrup Co., Philadel- phia, that makes full use its own equipment aid the economic production more the same type equipment. new department for tool and production heat-treatment phia probably one the most com- pact and efficient the country. All the furnaces are arranged semi- circle, ft. in. radius, front and recording instruments. instruments and furnaces are standard production items the com- pany. The compact but still far from crowded layout apparent the ac- illustration, and the ar- rangement permits the heat-treater work with unusual speed \long the reading from left right the accompanying illustration, are the following pieces heating and quenching (1) oil quench tank, using No. soluble oil. (2) trolled-atmosphere electric hard- ening furnace; this equipped with cracking furnace for con- verting fluid from overhead into furnace atmos- phere. (3) quenching tank. (4) Another Vapocarb-Hump furnace with cracker. (5) oil quenching (6) phere hardening furnace. (7) brine quenching tank. (8) Homo forced-convection electrical tempering furnace. (The has this furnace open the illustration.) (9) running water wash tank. (10) Another Homo convection tempering furnace. And the corner al- cleaning tank. control panel carries Micromax cording controllers for the five fur naces. The entire equipment repre $9,000, and the installation permits one heat-treater handle all tool and pro duction heat-treating for plant ploying 1100 people. (2) and (4) has chamber in. diameter and in. deep, and rated 11.6 kw. each, for furnace and cracker. These furnaces are used for annealing, for controlled hardening and for carburizing. The furnace oper- which the range which many the high-carbon and high-chrome steels are treated. These furnaces handle the carburization SAE 1020 cams, punches, dies, jigs, bushings, ratchet wheels, pawls, worms, ally all which are oil quenched hardness the neighborhood HEAT TREATING Rockwell These parts are either used used make integral same furnaces using protective at- mosphere, are used heat straight- carbon spring steel shafts, springs, washers, bushings, which are brine quenched initial hardness the Homo furnaces whatever hardness the particular part requires. The somewhat older type furnace, the Hump furnace (6), uses special- prepared atmosphere. Only and miscellaneous odds and ends, made straight-carbon steels are handled this furnace. The tool-type Homo tempering naces and (10) are the open coil type and operate 1200 deg. Each rated kw. maximum for the heater, with additional kw. for the motor. are used for tem- pering iron and steel parts heating non-ferrous metals such brass, copper, bronze and aluminum, all which are later quenched water. brass parts are for the most part supports and tapped duralu- min handled the form con- denser plates and clamps, galvanometer pointers, clutch arms, copper al- loys are the form tubing and inserts Some beryllium copper springs also are treated these units. THE IRON AGE, July 1939—47 | still tank method for clean- ing metal parts the oldest me- thod with respect physical arrangement, lowest initial invest- ment but usually highest labor cost widely used the smaller plant today, and with advanced knowledge the cleaning function serves its purpose very well. Because the expense the labor item cleaning operations any kind and particular with cleaning metal parts the process manu- facture, the tendency toward automatic equipment cially toward labor ing devices connec tion therewith. espe- The tank for still cleaning depends primarily the type cleaning performed and the size well the contour the shown the tank equipment required for moderate size plant. The arrange ment consists the pickling tank, cleaning and rinse tanks, all wood wood tank under construction the Mack Mfg. Co. plant located New Brunswick, This tank construc- tion very popular and consists tongue and grooved outer shell held gether heavy brass bolts and rods. The inner lining also wood but in. thick. All joints are filled with as- phalt and also applied the wood surface between the outer and inner tanks. Since wear comes entirely the inner lining, repair consists the replacement this lining when required. this construction, main- ments are kept minimum. director, Magnus Chemical Co., Garwood, N. 48—THE IRON AGE, July 1939 may may not applied the regular cleaning and_ pickling installation. However, conceded that the application heat shortens the time cycle for the operation and should used the pickling tank possible and almost essential the cleaning bath when are used, Oil, grease and other foreign matter are not removed the pickling oper- ation. Therefore alkaline cleaner OURTH Series Articles the Economic Aspects Metal Cleaning and Finishing should used preceding the pickling. Electric cleaning, which will dis- cussed future article, also used preceding the pickling operation. The manner the the liquid depends upon the facil ities available well the nature the bath. unwise connect the coil, immersed acid the vacuum return system. There fore coil heating the acid bath usually uneconomical because pres sure required for steam jet systems must high. This precludes the use exhaust steam. jet heater also objectionable due continuous dilution the bath which results loss bath control. Placing the steam coil directly the tank liquid and providing with baffle, such that shown Fig. and piping the condensate waste the pro- cedure. This type installation also provides agitation the bath, which desirable. Agitation and particularly aeration the solution increases the pickling rate, the time being cut much per cent for continuous agitation and aeration. One the more com mon ways obtaining agitation moving the work and down the bath. This may performed the use rope and block any one pickling shop where agitation use electric hoist obtained. The work transterred pickling tem, then lowered into the bath hoisting section the trolley atter which proceeds through the remaining operations the same way. This method not only suitable means for but port system for the labor costs are reduced materially. agitation and heating are must incorporated the equipment. has been fully ventilation dependent natural means scientifically designed hoods and duct work incorporating fan shown hood design which correct for the purpose, economical horsepower obtain given ventila- tion effect and reasonable first cost. The ventilation effect nearly uniform for all points the face the hood, feature considerable im- portance the ventilation quench tanks. alkaline solutions alkaline salts, except sulfides, steel may used the tank construction. the case the latter, steel may used heavily coated with asphaltum acid resisting paint. Lead lined steel tanks rubber lined steel tanks & q ° | | i ° ° ° q | | | 7 metal cleaning process the still tank method. Original cost low, but labor costs are high; reduce the latter there have been developed automatic and semi- automatic machines, all which are described herein may used acids but will not stand well caustic solutions plain steel better for caustic solu tions. The steel tank should sutficient heavy gage stand the chanical abuse, preferably gage heavier, and with all joints welded. The riveted tank often troublesome due leaks the joints and must thoroughly caulked supplemented welding. pickling does not remove foreign matter from the surface the work cleaning operation introduced. Cleaning the metal has become very important depends the surface appearance the finished article which affects sales appreciable extent, but also cleaning rests portion the produc- costs which also affects sales competitive market. many types industry cleaning affects the fit one part with another very large extent, and cleaning almost essential wherever parts are finished spected. example, the manu facture ball and roller bearings there are less than eight cleaning operations involved between the first rough machine cut and the boxed not always necessary obtain chemically clean surface; therefore, cleaning matter degree. For instance the Inc., plant Philadelphia, some cleaning operations are only intended remove the larger percentage the oil and grease between subsequent operations. One these the washing ball races between the oil quench bath fol- lowing the hardening operation and the tempering operation done electric furnaces. The quench oil must removed prior the parts going into the electric furnace matter reducing the maintenance cost the heating elements; there- fore, the parts are given per cent wash soda solution using per gal. water. The temperature the solution maintained 150 deg. About Ib. material are handled per hr., the handling taking LEFT 1G. cleaning and rinse tanks, all wood construction. This the arrangement favored moderate size plants. RIGHT 2—Wood tank under construction. are filled with asphalt. place means overhead trolley system and electric hoist. clean the surface, the cleaning solution must capable wetting that surface. Perhaps water the ordinary liquids used cleaning not wet; such instances, something must added the solution pro- duce this wetting effect. The addition the liquid must not only the proper wetting agent for the particular foreign matter the surface, but must penetrate that matter thoroughly removed. Since most THE IRON AGE, July 1939—49 : 3 ’ 7 7 and mixtures these with minera! and vegetable matter, usually called dirt, the cleaner must power penetrate the dirt, suspend for carrying away and emulsify the oil present. surface skin. For forms drops globules though the liquid were bag. Penetrate the bag with pin and the drop water down the pin, bag and all. How ever, that bag sort water skin which effect, for want better name, called surface tension. this surface tension water which makes possible for water form drops, needles float the surface, oil spread thin laver over the surface, thus well understood that all liquids well other matter possess surface which bounds them. Sreay In 3—Usual procedure heating the bath. The steam coil provided with baffle. cause two liquids mix, this bound ary “interfacial tension” the two liquids must broken down entirety. Cleaning essentially mat- ter decreasing the interfacial ten sion the combination elements considered, and the substance which produces the greatest decrease the interfacial tension the best deter- tank cleaning, the with cleaners water solution which not evaporate, such solvents do. \lkalies are not considered good cleaners, however they become useful when used conjunction with other chemicals which increase the capacity the cleaner emulsify, deflocculate and suspend dirt solution that such materials may readily removed rinse. Most these cleaners, used today, are combination al- kali and soap. Their alkaline range The nature the dirt re- moved from the surface must given ample consideration selecting the proper range the cleaner. Those 50—THE IRON AGE, July 1939 Fic. this shop agitation the bath obtained electric hoist. with industrial products read ily recognize most the dirt cer- tain percentages mineral oils along with other matter spread the parts handling, laying the floor, ete. Much the matter fatty oil which can removed the use any one several alkaline materials such caustic, soda ash and others. However, the quicker results are obtained the use cleaner which fatty oils are saponified, forming soaps. the amount soap formed reaction with fatty matter the dirt itself usually inadequate perform satis- factory cleaning necessary add helps the commercial metal cleaners. give the proper amount soap for speedy, thorough Depending upon the metal dirt, the the cleaning from 13. high fatty instance, materials matter stearic acid buffing compounds, grease drawing compounds, usually emulsify and leave the surface best solutions low pH, from Strongly alkaline solutions set such dirts sticky, slowly soluble soaps which dis- solve off only very Straight mineral oils come off best high pH, for instance 13. Aluminum, zinc, soft metal alloys must cleaned solutions low avoid alka- line corrosion, that from 10.5. Brass must cleaned not over 12.5 avoid heavy tarnish. Steel iron are the only metals safe clean tageous work with solutions low will the for the more alkaline solution the more disagreeable work with and the greater will the hazard from splash drip. Moreover, solutions low alkalinity rinse better than those con- taining caustic IG. 5—This hood design gives nearly uniform ven- tilation all points over the face the hood. oes = | | | application the centrifu- gal process for the purification and refining pig iron may regarded development the cen- process for the production castings. Perhaps the most striking evidence the effect centrifugal action the particles undissolved material present cast iron had from its effect upon the manganese sulphide. Manganese sulphide undissolved molten cast iron the temperature which iron ordinarily melted. The specific gravity manganese sulphide casting temperature sub- stantially less than that cast iron. Under these circumstances may expected that manganese sulphide will separated the inner surfaces the influence centrifugal action. That this may amply demon- strated sulphur print taken from the cross-section centrifugal cast- ing, which will show clearly how the manganese sulphide constituent con- centrated the inner surface. like manner other undissolved matter, having lower specific gravity than that the liquid metal, such slag particles, insoluble oxides and the like, are effectively separated. HURST Lichfield, England this the second section two-part article, the author describes the use the centrifugal casting proc- ess the refining pig iron. Last week, Mr. Hurst discussed the history and present status various cen- trifugal casting procedures. The effect mechanical movement the separation undissolved par- ticles from molten metal and the re- finement the grain structure the final solidified metal has been recog- nized for long time. Mechanical methods stirring, rocking and vi- bration have been proposed, partic- ularly for use connection with cast iron. Some years ago considerable prominence was given shaking jolting apparatus. the most ad- vanced design this apparatus in- vented the Continental engineer Duchesne, oil-fired receiver was means rotating cam device very chanical jolt ramming machine. The the quick succession jars the molten metal the receiver was claimed effect considerable provement the quality the cast- ings produced, and this was ascribed partially the degasification effect due the vibration. This process was Foundry Trade Journal July 22, 1926. Quite recently connection with the promoting soundness and closeness grain steel ingots arrangement has been patented German en- gineer which the liquid steel subjected very high frequency vi- bration audible frequency. Degasification Promoted The centrifugal process may re- garded special case mechanical movement and its use has pro posed for the purification such metals lead and copper. Many the early patent applications relating the centrifugal process had their object the promotion soundness, this being understood brought about the condition centrifugal pressure. Quité number attempts have been made utilize the effect the centrifugal action the refining THE IRON AGE, July | ° ° the grain size and the elimination sulphur and other undissolved matter both steel and Mechanism for the rotation ingot molds filled with steel has been designed with this object view addition attempting im- prove the soundness the ingots whole the reduction the amount the pipe. very early attempt connection with steel was proposed Sir Henry Bessemer his patent No. 2819 dated 1859. this patent was proposed pour the metal onto rapidly ro- tating table surface rotating within the enclosure mold casing. Under these conditions, reason the cen- action the molten metal was “thrown outwards the state globules, the extrication gaseous matters from being thereby favored.” The outer revolving formed the mold where the globules collected. clear that this attempt sub- ject molten steel centrifugal action was designed primarily promote degasification, and probably true that the agitation which molten metal receives when subjected such action does bring about disengagement the Several Processes Developed During more recent have been several processes designed for the utilization centrifugal action the purification pig iron. One these, due the Russian metal- the German patent 470/195 dated February 1926. The diagram Fig. will serve illustrate the principles involved. specially shaped container ladle arranged the spur gearing attached the base. This container, lined with suitable re- FIG. 5—Centrifugal process for the purification pig iron, developed Jarotsky. 52—THE IRON AGE, July 1939 fractory material filled with molten metal and rotated. Under the influence the rotation both the gases, sul- phides, and included slag particles are concentrated the base the para- boloidal depression the liquid sur- face due rotation and may remain the surface the molten metal after the rotation has subsided, the gases course being liberated. careful pouring bottom pouring the ladle the purified separated. Another process centrifugal puri- fication due the Belgian engineer sulphides and other suspended matters. the metal flows towards the de- livery end the tube the slag formed tends separate, and the molten metal and slag are delivered into stationary channel fitted with kind skimming brick designed retain the slag and allow the purified metal flow into the molds. centrifugal purification process operated England Bradley earlier degasification process described the Foundry Trade Journal, April the production high grade refined pig iron, refined malleable pig irons and refined alloy pig irons, this process cylindrical tired receiver used, capable hold- The metal treated taken from Purified cast iron Syphon Fixed receiver FIG. 6—Centrifugal process for the purification pig iron, de- veloped Vroonen. and has been described his paper before the International Congress Brussels 1935. esséntial portion the Vroonen apparatus consists conical tube lined with suitable refractory material and capable being rotated. The mode operation will understood reference the diagram illustrated Fig. this apparatus the molten metal delivered into the rotating conical tube issues from the melting furnace. The rotating tube inclined and under the influence centrifugal action induced the rotation, the molten metal tends distribute itself and flow down the tube the manner indicated the diagram. The molten metal during its passage through the rotating tube can treated with re- fining slags, for example sodium carbonate. This material added the metal enters the tube and the intimate con- tact obtained between the sodium car- bonate and the molten metal the mouth end the tube ensures the effective absorption the slag the the refineries and maintained receiver. modified form power- ful stirring device introduced into the molten metal. This device con- sists essentially four vertical rods coated with suitable refractory coat- ing and arranged rotate molten metal constant and uniform peripheral speed. this rotation the metal first agitated and then steadily acquires uniform rotational velocity. actual practice this velocity ar- ranged peripheral speed about 400 ft. per min. During this treatment the addition suitable refining slags made and these absorb the sepa- rated sulphides and The impurities and sulphur contents, separated, are absorbed the molten slag contact with the metal during centrifuging. After this operation the metal and slag subside, forming two lavers and the purified metal can tapped off readily. The diagram Fig. illustrates the principles embodied this process. The early stage this process brings about considerable claimed have effect causing | q | If or *. ec = = | | 4 degasification. The later stage accom- panied uniform centrifugal move- ment brings about separation the dissolved impurities and the process Whole obviously ensures thorough mixing the molten metal. Modern research connection with cast iron continually emphasizes the importance fine grain structure and fine graphite structure. cation the centrifugal process addition bringing about purification the separation the undissolved impurities may regarded method ensuring fine grained and fine graphite structures addition ensuring complete admixture and uni- formity composition the molten metal. Surtace molten iron during the centrifugal purification process. Maximum peripheral speed 400 feet per minute the special refining slags the centrifugal purification treatment and suspended impurities separated the centrifugal action contact with the refining --Surface the metal and the slag the completion the centrifugal refining process FIG. 7—Centrifugal process for the purification pig iron, de- veloped Bradley Foster Ltd. Semi-Bright Nickel Electroplate semi-bright nickel alloy electroplate now being produced commercially process the Hanson-Van Winkle- Munning Co., Matawan, manu- facturer electroplating equipment and supplies. This process was devel- oped supply need which has not been fully met either the bright heretofore available the conventional gray nickel deposits. Bright nickel deposits, generally known, are inclined somewhat hard. They are widely used because the savings which they effect the elimination most and, many cases, all the buffing the de- posited metal, although this saving lost the additional and coloring necessary the base metal. those cases where advisable touch the deposited nickel, difficuliy often encountered reason the hardness the deposit. Properties The coating described herein nearly bright the typ- ical bright nickels; the same time, buff much more easily the standard gray nickel nickel. Only the lightest “fanning off” loose, medium-speed buff required give the deposit deep lustre. The light pressure the wheel eliminates the danger cutting through the deposit ners and projections. The deposit mechanical forming operations with- out flaking peeling, having excel- lent adherence, even when deposited directly iron steel. Under properly tions, this deposit buffed copper brass may lustrous enough direc