The Iron Age 1941-03-27: Vol 147 Iss 13

i Democracies can act fast! Every hour every day American Industry turns out Defense production with ever-increasing speed ... And doing so, relies the speed... accuracy dependability such machine tools NEW BRITAIN AUTOMATICS. New Britain-Gridley Machine Division, The New Britain Machine Co., New Britain, Conn. complete line Multiple Spindle Screw Machines Capacity. Also complete line Four, Six and Eight Spindles Capacity. ¥ j ' f Hoskins Electric Furnaces are proving very useful production, and the Defense Training Program. make little ones and big ones, and they are described our new Catalog-58. Giad send you copy. KINS HEAT TREATING FURNACES HEATING ELEMENT ALLOYS THERMOCOUPLE AND LEAD WIRE PYROMETERS WELDING WIRE HEAT RESISTANT CASTINGS ENAMELING There more Furnace Tray than the alloy it’s made of. Its design just important—so that will not too heavy, and yet will strong enough withstand quenching strains, for example, without cracking. make trays that meet those requirements, according our customers. They tell our suggestions their previous designs have been helpful. The trays shown here are nothing very special, but are just samples. Our castings are mostly the well-known 12-24 and 35-15 nickel-chromium alloys. All melting done high- frequency induction furnaces, which provide very close control composition and quality. For years have specialized only those alloys that require the closest kind technical control. Tailor-made, rather than shelf goods. you want better trays, write us. Hoskins Manufacturing Co., Detroit, Michigan. ; i 5 — MARCH 27, 1941 VOL. 147, NO. VAN DEVENTER President and BAUR Vice-President and General Managing Editor News Editor Technical Editor OLIVER Machine Associate Editor Editor WINTERS Art Editor Washington Editors MOFFETT JAMES ELLIS Resident District Editors CAMPBELL HERMAN KLEIN Pittsburgh Chicago Cleveland Detroit Editorial Correspondents DEARING ROBERT McINTOSH Buffalo Cincinnati FRAZAR CHARLES POST Boston San Francisco HUGH SHARP JOHN McCUNE Milwaukee Birmingham SANDERSON ROY EDMONDS Teronto, Ontario St. Louis LEROY ALLISON Newark, Editorial Short Cuts Success Technical Articles High Speed Steel Punch Press Handling Time Finishing Die Castings Book Molding with Green Sand Core Gas Technicians Discuss Developments New Equipment Features the Assembly Line Washington the West Coast Fatigue Cracks News and Market Reports News Industry Machine Tool Activity 128 Personals 116 Non-Ferrous Market 129 Obituaries 118 Scrap Market and Prices 130 Metal Working Activity 119 Construction Steel 132 Comparison Prices 120 Iron and Steel Prices 134 Summary the Week 121 Ferroalloys, Pig Iron The Industrial Pace 122 Warehouse Prices 140 District Market Reports 124 Sales Possibilities 142 Products Advertised 156 Index Advertisers 189 Copyright, Chilton Company (Inc.) DIX, Manager Reader Service Advertising Staff 621 Union Bldg., Cleveland Herman, Chilton Bldg., Philadelphia Hottenstein, 1012 Otis Bldg., Chicago Leonard, East 42nd St., New York Peirce Lewis, 7310 Ave., Detroit Ober, 100 East 42nd St., New York Warren, Box 81, Hartford, Conn. Don Harner, 1595 Pacific Avenue, Long Beach, Cal. Member, Audit Bureau Circulations Member, Associated Business Papers Indexed the Industrial Arts index. Pub- lished every Thursday. Subscription Price: United States and Possessions, Mexico, $6.00: Canada, $8.50; Foreign, $12.00 year. Single copy, cents. Owned and Published CHILTON COMPANY (Incorporated) Publication Editorial and ice Executive Offices Chestnut and 5éth East 42nd St. Philadelphia, Pa. New York, U.S.A. U.S.A. OFFICERS AND DIRECTORS MUSSELMAN, President JOS. HILDRETH, GEORGE GRIFFITHS, EVERIT TERHUNE, VAN DEVENTER, BAUR, Vice-President Vice-President Vice-President Vice-President Vice-President WILLIAM BARBER, Treasurer JOHN BLAIR MOFFETT, Secretary JULIAN CHASE, THOMAS KANE, CHARLES HEALE HARRY DUFFY @) Oo oO q Sure Quality Steel Fast Service, Too! Ryerson service American industry combines quick shipment from vast, conveniently-located stocks and quality certification under which every ton steel this huge reserve carefully chosen conform definite quality standards. Ryerson Alloy Steels are from selected heats that meet specification—a “specification within are delivered you with complete heat-treating data. time lost testing your plant; spoilage eliminated; uniform response assured. Yet, like all other Ryerson steels, Ryerson Certified Alloys cost more. With steel brisk demand, you can have dependable source supply, and safeguard quality, too, ordering from the nearest the ten Ryerson plants. the need urgent, suggest you not wait for quotations but mail, phone wire open order. Your steel will shipped promptly and billed standard prices. Stock List sent request. Joseph Ryerson Son, Plants at: Chicago, St. Louis, Cincinnati, Detroit, Buffalo, Boston, Philadelphia, Jersey City. | | | ; a ul : 4 = % ‘§ MARCH 27, 1941 ESTABLISHED 1855 Short Cuts Success IMES have changed. the old days boys school age read books Horatio Alger and similar authors and were imbued thereby with ambition succeed the hard way. Nobody had then discovered the modern short cuts success. The idea then was that one must start the bottom and through years hard work, perseverance and thrift might some day find himself the top some modest business enterprise and with enough money per- haps leave little charity and something his estate. Even people who did not make the grade themselves must have be- lieved this approach the goal success, because the men who did attain through this avenue were respected their communities and looked upon public benefactors well good business men. Usually success this sort was the result from years hard work and self-sacrifice the part some one individual small group men who had the persistence and patience carry spite all obstacles. They built painfully but solidly and while the building was primarily done the golden horse-and-buggy era free enterprise, some our best small and medium sized concerns, and fact some the large ones too, still carry the tradition. That was the tradition and procedure that made this country what is, perhaps, more accurately what was, before the discovery the shortcuts success. One the first shortcuts success put into practice was the financing shortcut. Smart people with money observed that these patient plodders who had worked long and hard establish enterprises found themselves pinched times for money. And when the pinch became severe enough, was possible put squeeze play into effect and get control the results years other people’s work for few dollars. This method, while was successful for while had its disadvantages, because the people who employed had least have some money available make work. Not much, but some. Two other shortcuts success have been devised since that time that enable the taking over somebody else’s business without putting penny. you are failure the law, business, for example, you can into politics. Then perhaps you will elected Congress and will have the power impose taxes. Through that method you can confiscate the profits business without having undertake the responsibility managing it. But that method too has its disadvantages, for elected appointed office one’s fellow citizens, man has usually possess least the rudiments respectability and some degree public acceptance, Less onerous and taxing the third shortcut. consists setting one- self modern labor leader. Even communists are acceptable for that. What the use working hard, like Henry Ford did, for years build business when you can seize control without ever getting callous your palm? — q t | | ® | | ' | \ € 3 STEEL for the Needs Great Nation Only few seconds will pass until the steel shown here will flash, more than miles hour, from the finishing stands the Inland 44-in. continuous sheet and strip mill. ribbon steel, true specification and tolerance—a steel ribbon its way meet the needs Great Nation. Not only this continuous mill, but every Inland department, are exhibited this same degree energy, insistence upon uniform quality, and the ability give service. 7~ Such results are only possible with the most modern equipment. They come also from the calibre the Inland men, trained the high- est degree steelmaking skill. Men who are alert the needs Great Nation. Inland today supplying America with important part its steel requirements— whether they are for normal suits, for the accelerated pace national rearmament. SHEETS STRIP TIN PLATE BARS PLATES STRUCTURALS PILING RAILS TRACK ACCESSORIES REINFORCING BARS pur BARS HEN section industry has historical background substantial maturity, only nat- ural the result the high de- gree stability achieved for given demands, that the production tends remain conventional lines set earlier times the crafts- men and workers. High speed steel production falls into this class, where many producers still regard their products possessing pecu- liar properties inherited from purely convention. Some the conventional pro- cedures have been found true after scientific analysis. For in- stance, the hardening turning tool from the blacksmith’s hearth. Such tool was held the hearth until the nose was seen fuse, and after air blasting was ground back sound metal and found behave splendidly turning tool. Thus, the most effectively hardened portion having grain size approaching the ideal was present the portion the tool required the work. the other hand many prac- tices have often proved per- PINDER Metallurgist, William Jessop Sons, Ltd., —Data recent English production research, includ- ing adaptation secure more homogeneous ingot structure. Sheffield, England sonal fancies. Modern demands have called for high standard and consistent results high speed steel products, and the basic prin- modified studying and applying the conclusions practical re- searches, some which are set out below: (1) High speed steel production. (2) High speed steel tool fail- ures. (3) Cutting affected met- allurgical considerations. regards high speed steel in- got production, will readily realized high speed steel produc- tion that the most important fea- ture, after taking precautions make certain that the steel will cast into sound ingots, insure the optimum ingot structure. the best under normal production the high speed steel ingot highly heterogeneous, even outer dendritic shell, while along the axial zones the heterogeneities are most severe. This readily il- lustrated the photomicrographs, Fig. which are taken from the outer dendritic zone 8-in. square ingot and the axial zone the same ingot positions midway between the top and the bottom. expected therefore that the greater the ingot section the more marked will the difference structure between the outside and center. This state affairs persists because freezing pro- ceeds inwards from the ingot mold walls, the liquid portions become increasingly richer carbon and alloying elements. This phenomena can readily appreciated re- ferring the modified equilibrium complex carbide-iron diagram. addition, the larger the ingot the larger the axial zone, and therefore this portion retains more super- heat. Consequently the freezing rate slow. The chief considera- tion producing high speed steel ingots more uniform structure throughout the section is, there- fore, the reduction the freezing time between the outside and the center the ingot. The principal factors affecting this are: (a) The casting temperature. (b) Ingot mold design. The cross-section the in- got. The most difficult feature con- trol (a), but this has been ren- dered much easier late the THE IRON AGE, March 27, 1941—39 ‘ } 7 | | | i | | most the | one are q nts— i high speed steel ingot very heterogeneous. These photomicro- graphs show the structure the outside (left) and the center (right) square ingot, the middle the ingot. 200 diameters. use the Schofield-Grace quick immersion pyrometer for measur- ing liquid steel temperatures. should also remembered that for increased size lower casting temperatures can used. the casting temperature too low and the rate which the mold fills slow, then gas occluded large amounts and unsound in- got the result. crucible high speed steel ingot can cast relatively low temperature because the rate teeming from the pot can very rapid. regards (b), the thicker the walls the ingot mold, within rea- son, the quicker will the freez- ing rate across the section the ingot. Factor (c) governed the type product made, and should noted that wherever pos- sible minimum reduction cross-sectional area the original ingot per cent should ar- ranged. Once the ingot solid the struc- ture can only modified appre- ciably hot work, and there are serious limitations what can accomplished when given sectional sizes. One recent development which gives more homogeneous ingot structure represented the “Durville This process was originally conceived for the production non-ferrous alloy in- gots, which gave rise large num- bers surface seams when cast the normal way. Work the re- search department, Woolwich, En- gland, has shown some interesting results various steels. 40—THE IRON AGE, March 27, This process requires that the mold and ladle fixed together such way that the closed side straight line, shown the sketch, Fig. Thus, when the ladle and mold are turned through angle 180 deg. given speed the mold becomes filled with the metal relatively quick rate. Such method allows the metal cast low superheat without mum trapped gas. Casting steel from normal ladle such low superheat would prove impractica- ble because the metal would tend freeze round the nozzle and gas would trapped the ingot. Al- loy steel ingots cast this way tion ingotism, and solidification has occurred over very much re- duced freezing range. Applying this idea high speed steel, means that freezing can occur the same time from many more centers than normally the case. finer macro grain the result and the carbide envelopes are finer. When casting high speed steel ingots the normal method compromise must made between too high and too low casting tem- perature. Casting too low tem- perature would result un- sound ingot due the fact that gas coming out solution would trapped rapidly solidifying ingot, while feeding through the head would out the question. present the largest ingot cast the “Durville Process” has larger ingots could cast success- fully after trials had been made. Limits the size ingots would still persist, but where large tools noted that first slightly reduc- ing the cross-section the ingot then cutting into two and upending larger cross-section than the original ingot and continuing nor- mal forging from this section, the scope tools made would much larger. Apart modification the “Durville Proc- ess” might lead larger ingots being produced. Although the tool maker ask- ing for high speed steel free The Durville Process operates manner. The steel may thus cast low super- heat without turbulence. means proved that moderation such heterogenieties are them- selves harmful. the contrary, Grossman and Bain have noted the presence such segregates tools which have given excellent service, and the author stantiate this evidence recalling examples which have been noted speed steel tools which had given superior service. does seem desirable that sample high speed steel free from carbide segregates should compared for performance with one which they are present but otherwise similar all respects. The former sample could readily . | prepared careful selection the outside portion the ingot toward the bottom end. Casting and Forging During investigation de- termine the effect ingot size the carbide structure, 4-in., 6-in. and 8-in. square ingots were pro- duced from ladle having stand- ard nozzle size and constant cast- ing temperature, 18-4-1 and 18-4-2 steel. Both the ingots and cogged bars were examined six positions (at the outside and cen- ter the top, middle and bottom positions). The ingot structures will re- viewed first. Sections examined from the outside the ingots within the dendritic zones showed very little difference whether taken from the top, middle bottom positions, and only minor differ- ences the structure were noted sections prepared include the axes the ingots from the bottom positions but above the dendritic zone. The most striking differ- ences were noted internal axial positions the top and middle positions, the carbide envelopes being thicker the 6-in. and 8-in. ingots than the 4-in. ingots. These features are shown the taking the sectioned ingots and forging them common size in. square, the structures the bars were examined the six positions previously indicated. result the forging opera- tions the carbide envelopes under- distortion and local diffusion which facilitated combina- tion mechanical work and tem- perature. This results redis- tribution the carbide which along the axial portions show discontinuous bands, while within the zone which corresponded the dendritic shell the ingot the car- bide much more uniform and free from banding. This effect graphs showing the outside and center portions 6-in. square ingot, Fig. number workers have de- scribed the redistribution the carbides being due the break- ing and fragmentation the car- bide plates forming the eutectic. However, felt that this de- scription hardly true com- plete. actual breaking frag- mentation did occur this would most likely lead bursting the development small discon- tinuities the metal. Moreover, difficult conceive how rela- tively hard but ductile carbide chiefly concentrated along the axial zones could easily fragmented when embedded very soft mat- rix, which are the conditions ob- taining forging heat. Further, the energy required fragment the carbide under these conditions would much more likely burst the metal. What appears happen that result surface ten- sion together with diffusion, the carbides tend ball and this 3—Ingot structures internal axial positions. middle 8-in. square ingot (upper left), and bottom same ingot (lower left); middle 6-in. square ingot (upper middle), and bottom same ingot (lower middle); middle 4-in. square ingot (upper right), and bottom same ingot (lower right). All views diameters. THE IRON AGE, March 27, | | 2 er 4—Carbide envelopes undergo distortion and local diffusion during forging. Photomicrographs show center (upper left) and outside (upper right) middle 6-in. square ingot; center (lower left) and outside (lower right) bottom 6-in. square ingot. All views diameters. accelerated considerably me- chanical work leading finally much more equitable distribution. Comparing the results car- bide distribution after forging each portion the ingot bar, has been found that repolishing section etched dilute nitric acid solution, followed agent and repeating the last two operations often necessary produce good contrast, exam- diameters gives very good idea the general distribution the car- bide. This method was used pro- ducing Fig. and this effect shown graphically Fig. for 6-in. square ingot the outside and center the top, middle and bottom positions. examination the carbide distribution magnification 200 diameters, without that the low power described above, was not found useful and was actually some- times misleading. Both the high and low power examinations were 42—THE IRON AGE, March 27, 5—Graph- ical indication distribution carbides, for 6-in. square ingot the outside and center the top, middle and bottom positions. Outside Center considered necessary give com- plete picture the carbide distrib- ution. This method approach led the following conclusions. (1) That from all ingot sizes the best carbide distribution was obtained the bottom third the ingot. (2) That given normal dis- card the next best position was the top third the ingot. (3) That the center third por- tion was the worst position the three, there being sharp divid- ing line between the three portions. duction area, the 4-in. square ingot had best carbide distribution the three, while there was little differense between the 6-in. and 8-in. ingots. (5) reduction the 134-in. square cogged bars 1-in. diameter rounds established the superior carbide distribution the 4-in. square ingot. (6) Special tools requiring the best possible distribution made from selected portions the ingot. (7) Finally, not possible make all high speed tools from 4-in. ingots, and carefully con- trolling the casting conditions the lines already stated, improved ingot structures should obtained larger sized ingots. Part the same investigation was devoted noting the effect Outside Center J | ; ' att at i « & different forging procedures the structures 8-in. and 6-in. ingots. The procedures were follows: (1) Upsetting after cogging the ingot 3%4 in. square, and recog- ging the direction the ingot. (2) Normal cogging with maximum amount corner work. (3) Slabbing and cornering. (4) Forging the press. the four methods, slabbing with adequate cornering gave slightly the better carbide distribu- tion, and adequate cornering proved beneficial reducing minimum the form structures. These structures, present, can readily seen after hot etching, and tend persist square and Their presence due lack work the corners the billet bar, thus facilitating the migra- tion impurities starting from the center and decreasing inten- sity toward the outside along the original diagonals the ingot. This part investigation again showed the necessity pro- ducing the ingot the finest pos- sible structure consistent with soundness. the production tools where upsetting operation neces- sary, per cent reduction straight forging should given where possible, before the upset- ting operation. Investigations have shown the necessity for this, normal upsetting operation does not redistribute the carbide any marked extent bands persisted the forged bar. Benefits are gained how- ever other directions insofar that the metal more dense after such operation and the mechan- ical strength and toughness are more uniform all directions. Ed. Note:—Next week the author will conclude with data high speed steel tool failures, metal- lurgical aspects machining, etc. Punch Press Handling Time Halved built specially handle the 10-ft. sheets electric steel from which a.c. and d.c. motor lamina- tions are punched the plant the Reliance Electric Engineering Co., Cleveland. Each truck will carry tons sheet time, piled surface with slope that matches the angle tilt the press plate. This makes unnecessary any additional positioning the sheets they are fed between the blanking dies. combination air-hydraulic lift, over which the loaded truck run beside the press, used elevate the sheets exactly the right work- ing level. The lower edges the sheets rest against angle iron up- rights over which are fitted freely sliding sheet guides containing hardened vertical steel rolls. Pre- paratory starting the blanking operations, the operator frees the top sheet pulling toward him and then letting slide back against the guides. These, mean- while, have dropped tightly against the surface the remaining sheets. The top sheet, sliding onto knife- edge projections the guides, has its lower edge raised slightly above the rest the sheets and its upper yond the edge the sheet pile. The decreased area left contact with the sheet below, and the better hold provided the projecting edge the top sheet, serve facilitate the operator’s manipulation the ma- terial from the truck through the press. Previous practice has been shear the sheets, approximately ft. size, into 1-ft. sec- tions; these are fed into the press from 2-ft. high piles. The use the specially designed trucks has permitted revising the procedure considerable advantage. For the same size blanks, the 10-ft. sheets are slit into three strips equal width. These are loaded onto the truck, elevated beside the press shown the accompanying illustra- tion, and fed into from the same height piles. The same number blanks obtained with the new method cutting the sheet; but with reduction the number major handlings from nine three, the handling time that saved amounts approximately per cent. HIS truck, built with sloping floor and special positioning fixtures, cuts the number handlings steel sheets from nine three and the handling time approximately per cent. THE IRON AGE, March 27, | | j | | Finishing Die Castings... LATING and other finishing zinc alloy die castings, espe- cially for the automotive in- dustry, now done standardized specifications which insure high quality. Nevertheless, unusual find two shops which follow pre- cisely identical methods and the equipment used varies widely. One the latest and finest set- ups for such work found the new plant the Gerity-Adrian Mfg. Corp., Adrian, Mich. This plant and its equipment were de- signed especially for such work, large part which for the auto- motive industry. Some zinc alloy die castings are plated for other industries but, simplify proce- dure, these follow the same rou- tine with certain minor exceptions. castings are produced the plant. All are shipped die casters, chiefly from plants To- ledo. Suppliers make point producing castings maximum surface smoothness that polish- ing and buffing operations are minimized. small proportion the cast- ings received, including such items faucet handles for the plumbing trade, are tumble burnished, but much the largest part requires some grinding (or sanding), especially parting lines, well buffing prepare the castings for plat- ing. Tumble burnishing done dry wood-lined barrels about in. diameter. typical charge about 1500 faucet handles which, together with dients, makes the barrels about half full. Burnishing done three steps—coarse, medium and fine— which require from three hr., depending the initial smoothness the castings and the grade burnish required. the initial “cutting down” burnish, fruit pit granules and abrasive are used and the barrels turn about operations sawdust used with fine abra- sive, such tripoli and with the barrels turning more slowly, down 44—THE IRON AGE, March 27, 1941 Gerity-Adrian Mfg. Corp., up-to-the-minute shop designed for efficient handling large volume. ° ° ° JAMES GERITY, Jr. Gerity-Adrian Mfg. Corp., Adrian, Mich. ° ° ° r.p.m. the fine burnishing. The latter gives high luster though one not quite equal wheel buffing. great deal polishing done muslin wheels which abrasive general, the part guided hand, but some circular parts are held rotating heads arranged pairs that the operator can load one part The size wheel varied, are the number grinding operations, fit the work done and reach all surfaces which require polishing. For some work, such horn rings, where necessary grind spaces such the open- ings between spokes, excellent use made special form sander using l-in. abrasive belt running over three pulleys, one which mounted the driving motor shaft. The second pulley idler and the third and smallest, about in. diameter, the end pivoted arm, making pos- sible for the belt reach into openings otherwise hard get at. angle bracket carries the idler pulley and the pivoted arm and adjustable along the bed the ma- chine that the desired belt ten- sion readily maintained. suc- tion outlet below the belt carries off abrasive dust. This form grinder also useful for reaching into recesses between projecting parts which are too close together polished ordinary grind- ing wheels. Some castings received regularly sufficient quantities warrant the use automatic grinding and polishing machines with such equipment. these the automatic polishing are advanced forms set different angles | : Bee ] | y 5 angles cases, the casting first placed wooden form holder made fit the chain which through the machine. The holder then placed the slowly moving chain and carried forward suc- cessively under each the polish- ing and buffing wheels, which six are commonly used. the end the machine, the casting, complete- polished and buffed, removed and hung chain conveyor which toward the cleaning ma- chine, the form being returned the loading end the polishing ma- RIGHT set four tumbling barrels employed for dry burnishing some small die castings, such faucet handles. machines used for polishing rear fender ornaments. The die castings chain which carries the parts successively under six polishing wheels ABOVE PECIAL form sander which belt run over three pulleys, the smallest which the end lever, making possible reach into recesses hard grind other means. THE IRON AGE, March 27, 1941—45 | | | | chine receive another casting. Some polishing done ordinary belt sanders when flat surfaces are finished. Buffing accom- plished with stitched muslin wheels which are kept supplied with stick polishing compound. Castings are commonly toted the polishing stations hand trucks, often the cartons end the copper and nick which they are received. After pol- ishing, small castings are placed wooden trays and larger ones are hung overhead chain convey- which advances them toward the cleaning machine. Near the latter, each casting inspected and, when passes inspection, racked for passage through the cleaning ma- chine. Cleaning done with solvent preparation described neutral emulsion synthetic and organic IRON AGE, March 27, solvents.” Racks castings chain conveyor first enter tank the solution which they soak for sec. 190 deg. the second stage, another supply the same solvent applied spraying un- der pressure. Then the castings are rinsed water 120 deg. F., and again water 130 deg. They issue bright and clean and ready racks issue from the cleaner and rinse, they are removed and hung frames for passage through Crown plating machine designed dip them automatically successive tanks forming the plating line. The steps this process include: (1) Dip for sec. per-gal. commercial alkaline cleaner plating line, showing, the foreground, one the carriers for plating racks and, beyond it, the copper plating tank. for plating, which follows imme- diately. feature the cleaning the removal sediment (chiefly buffing compound) continuous flotation which designed keep the solvent clean and suitable for repeated use. Its checked hourly make sure that the solvent remains the required condition. All the solution drawn off and cleaned filtration once hr., with about per cent recovery, stated. during which the castings are cleaned anodically. (2) Rinse for sec. cold water. (3) Dip for sec. cent sulphuric acid neutralize any remaining cleaner and re- move any oxide film remaining the castings. (4), (5) and (6) Successive rinses, usually cold water, al- though tanks with steam coils for heating desired. (7) Plate with copper min. 2300-gal. tank during which time the castings are advanced from end end the tank chain. The tank has conventional Rochelle salt solution which heated mairtain temperature 163 170 aeg. Current supplied 6000-amp. generator give current density amp. per sq. ft. The result copper plate having thickness 0.0003 0.0005 in. (8) and (9) Water rinses sec. each. (10) Dip 0.75 per cent sul- phuric acid remove any oxide film. (11) Rinse water. (12) Bright nickel plate for min., during which the castings are IEW loading end the auto- matic chromium plating line. chain conveyor carries the plating racks (each which, this case, ac- commodates single large die cast radio grille) through the several tanks the line. ~~ | castings are chromium plated, they are removed from racks (left) and are placed the belt conveyor which carries them through inspection packing stations. advanced through 4000-gal. tank with automatic agitation. The solu- tion maintained 135 deg. plus minus deg. Three gen- erators, with total capacity 13,000 amp., supply current density amp. per sq. ft. and apply plate ranging from 0.0009 in. 0.001 in. thickness. (13) Cold water rinse, sec. (14) Hot water rinse, sec. result this treatment, castings issue with bright nickel plate and are ready for chromium plating when, usual, specifica- tions call for this. some cases, however, small amount buffing may required any areas the castings are not sufficiently bright meet requirements. Both the nickel and the copper solutions used are continuously filtered and continuously heated, the heating being done heat exchangers. the beginning the chro- mium plating line, the castings, pre- viously nickel plated, are first given 25-sec. cathodic alkali cleaning, are spray rinsed, given 10-sec. dip 48—THE IRON AGE, March 27, 1941 water, are again spray rinsed and then enter the chromium plat- ing tank. This plating line includes the use machine which ad- the plating racks means chain. The average plating time min. current density 150 250 amp. per sq. ft. This results chromium plate about 0.00002 in. thickness top the nickel plate. the end the plating, there follows cold water dip and cold water spray, after which the racks castings enter warm air duct, traveling toward heater which warms them gradually. When castings issue from the duct they are dry and are removed from the racks and the latter continue back toward the cleaning tank. the way, the racks receive treatment remove any chromium salts and are ready for re-use. The same racks used copper and nickel plating are used also chromium plating and there unloading castings from the racks after nickel plating ex- cept the case castings which not issue from the nickel plat- ing sufficiently bright direct chromium plating. All tanks are set with their bottoms well below floor level that operators work floor level. All long-run work handled the automatic tank setup just de- scribed. Considerable work plated two 1500-gal. cop- per tanks and four 1500-gal. tanks designed for hand operation. the end the chromium plat- ing line, all castings are de-racked and placed belt conveyor. The same true those castings which issue from nickel plating and not require chromium plating. The belt conveyor carries the castings past inspectors who check the plating and return any castings which plating imperfections are found. Those which pass inspection con- tinue the belt and, required, are taken off stations where tap- ping done and/or inserts are put place. Castings which require further work continue pack- ing stations where they are placed cartons for shipment. Occa- | sional castings receive light color where the plating not sufficiently bright meet require- ments, but the proportion such small. Many castings, however, require the application enamel re- cesses provided for the purpose, and those enameled are shunted into room provided with the latest form equipment for this purpose. The room sealed prevent the entry dust and supplied with filtered air under slight pressure that leakage, any, always outward rather than inward. All plated work handled with white gloves (although they were omitted when the graphs were taken) avoid finger marking castings. Four spray booths are provided and they have bottom suction outlets that any sprayed enamel which adhere castings masks drawn downward and cannot reach breathing level. Masks are special type made originally plating steel iron onto die casting and afterward stripping the heavy plate which thus fits the casting perfectly. The mask trimmed, course, that only the parts the casting sprayed are exposed. Edges the mask, which mark the cut-off, are turned downward short distance instead being perfectly Thus, when the letters name, for example, are being masked (the letters being raised sprayed background the cast- ings) the edges letters are part- fully covered the down- turned edges the mask. con- sequence, these plated edges remain bright (as well the face the letter) and the depth the letter thus revealed makes stand out prominently against the enamel the background. Masks made this way can used repeatedly, some cases for many times without cleaning, the down- turned edges the mask help keep the back face the mask free enamel. When masks, which are made duplicate, require cleaning, they are dropped solvent and the other one the pair, previously cleaned the same way, put use while the first one cleaned. Immediately after spraying, cast- ings are hung chain conveyor which carries them through oven which the enamel baked for about min. 250 deg. four spray booths the room where die castings are masked and portions are spray enameled over parts the plated surface. Beyond the operator seen the bottom oven which the enamel baked cast- ings are carried through chain conveyor. The enamel quick drying type made for the purpose and has ex- cellent adhesion, even the plated finish over which, course, applied. Ovens are the type hav- ing electric heating units and with top vents through the roof for dis- charge spent air. When the the end the oven, castings con- tinue the conveyor until cool and then are removed and packed for shipment. The spray room alone designed handle about 25,000 castings day some 3000 per hr. Except for toting castings re- ceived from outside suppliers the point where processing starts and toting cartons finished castings handling done conveyors. There thus substantially con- tinuous flow parts from the re- ceiving end the plant the op- posite shipping end, the whole layout having been made regular flow view. Although the plant does jobbing business, the items handled are primarily quired large quantities and largely this which makes feasible efficient layout. the same time, however, smaller quantities castings can and are handled expeditiously though with less use conveying equipment. All except very small percentage the castings handled are alloy, but some the hand tanks some aluminum alloy die castings are plated. WENTY-EIGHTH Series Articles the Technical and Economic Aspects Metal Cleaning and Finishing THE IRON AGE, March 27, 1941—49 q 4 i 3 | | | , el t | | if | | i 2 ire | it ARC WELDING —Continuation series lessons enable beginners master the fundamentals bare and shielded arc welding techniques. ESSON No. 18: Object make horizontal butt weld between two vertical plates. Apparatus used Westinghouse Flex Arc welding machine, chisel, hammer and wire scratch brush. steel plates with 45- bevel the end one, and 5/32-in. diam- eter Flex Arc welding electrodes. INSTRUCTIONS: horizontal butt weld between vertical plates one the most difficult welds make joint designs may used but all cases they should proportioned that the kerf angle the top plate not too small. wide angle single bevel joint, shown Fig. 34, often preferred the normal single vee joint (Fig. 34) because affords better fusion the top plate. The weld should made us- ing series string beads. Small diameter electrodes are preferred especially for the first passes. short arc must maintained all times and care taken prevent roll and overlap. Depositing metal the top kerf surface approximates overhead welding, consequently spe- cial care must taken obtain complete fusion. PROCEDURE: Set the polarity re- 50—THE IRON AGE, March 27, versing switch straight polarity, adjust the welding current 150 amp. and tack weld the plates to- gether shown Fig. 35. Mount the plates the vertical position and securely ground them the welding table. Deposit the weld making five string beads the sequence shown Fig. 34. sure hold short are all times. When depositing beads and point the electrode upward that complete fusion will obtained the top plate. After the weld made have the instructor inspect for appear- ance. Following the instructor’s inspection, nick the weld and break it. The exposed fracture must show complete fusion and the entire ab- sence slag inclusions, poor pene- tration and gas pockets. Repeat this exercise until weld can made. ESSON No. 19: Object de- posit beads weld metal overhead surface. Apparatus used Westinghouse Flex welding machine, chisel, hammer and wire scratch brush. Material used steel plates in. thick and in. diameter Flex welding electrodes. INSTRUCTIONS: Welding the overhead position one the most difficult positions which weld. The molten deposited metal has tendency run fall downward result the pull gravity, consequently requires great deal skill deposit smooth uniform bead. The major portion metal transfer from electrode occurs the formation drops, consequently the welding technique must such transfer the molten drops from the electrode the plate being welded. Holding short essential the deposition metal the overhead position. long arc held difficulty will obtained obtaining proper metal transfer and preventing the deposited metal tending run downward the form drops. The electrode should pointed approximately right- angles the plate toward the weld angle about deg., shown Fig. 36. Most overhead welding made string beads although slight weaving motion can sometimes used. Excessive weaving must prevented because tends create large pool metal that very difficult control the overhead position. PROCEDURE: Set the polarity re- versing switch straight polarity, adjust the welding current 100 amp. and tack weld plate the horizontal position that welding can done the underneath side. (1) Practice striking the are overhead until can struck and maintained. (2) After the art striking has been mastered, deposit short string beads holding short arc. In- spect the beads for smoothness, undercut, ete. (3) Repeat the same exercise holding medium and long and note the difference the appear- ance the beads. (4) Deposit bead weaving about in., using shaped weaving motion. (5) After possible make uniform bead the overhead position, make test piece shown Fig. 37. ESSON No. 20: Object make butt weld the over- head position. Apparatus used Westinghouse Flex Arc welding machine, chisel, hammer and wire scratch brush. Material used two and diameter Flex Arc weld- ing electrodes. INSTRUCTIONS: The deposition butt weld the overhead should string beads outlined Lesson No. 19. When the joint becomes wide, slight weave may used but this not recommended for the beginner. short arc must held obtain proper metal trans- fer and make smooth uniform bead. the beads are rough advisable chip the rough surface off, otherwise poor fusion and slag inclusions will obtained. The most difficult task making overhead butt weld obtain complete fusion with the first pass without burning holes the thin edges the plates the root the weld. Periodically lengthening the arc when the metal appears get too hot will greatly aid pre- venting the burning holes. PROCEDURE: Set the polarity re- versing switch straight polarity, adjust the welding current ap- proximately 100 amp., tack weld two plates together form deg. single vee butt joint. Mount the plates the horizontal position that they can welded the overhead position. Weld the plates together us- ing five passes, shown Fig. 38. Hold short arc and take special care make uniform beads free from undercut. Clean each bead be- fore depositing the next. Chip all welds that are not smooth. After the welded joint completed have the instructor inspect it. Follow- ing the instructor’s inspection, nick the weld and break it, Repeat this exercise until weld free from gas pockets, slag inclusions, poor fu- sion and can obtained. ESSON No. 21: Object make fillet weld the over- head position. Apparatus used Westinghouse Flex machine, chisel, hammer and wire scratch brush. Material used two diameter Flex welding elec- trodes. INSTRUCTIONS: Fillet welds may made the overhead position with the plates the horizontal and vertical position with both plates positioned angle deg. with the horizontal, shown Fig. 39. fillet weld made with plates 45° ' Single bevel Single vee 34—Types joints used for horizontal butt weld between 35—Technique follow for two vertical plates. horizontal butt weld between two vertical plates. Left right Left right Right IG. 36—Method pointing procedure fol- electrode deposit beads lowed for overhead surface. weld metal overhead surface. IG. weld overhead position. 40—Technique methods mak- ing fillet welds the overhead position. llow for making fillet weld the over- head position. THE IRON AGE, March 27, n ite re- ty, de. 1as In- \ | ead similar butt weld, conse- quently will not considered separately this course. Also fillet welds lap and tee joints are made tiie same manner, conse- quently only the tee welded joint will considered this lesson. Overhead fillet welds are general- made series string beads similar the method discussed for overhead butt welds. PROCEDURE: Set the polarity re- versing switch straight polarity, adjust the welding current ap- proximately 100 amp. tack two plates together form deg. tee joint, shown Fig. 40. Mount the plates shown Fig. that fillet weld can made the overhead position. Use three beads make the weld. Hold short all times and clean the weld between passes. Chip the deposits when necessary in- sure sound fusion and freedom from slag inclusions. After the instructor spected the finished weld for ap- pearance, fracture the weld. The weld must show complete penetra- tion and free from gas holes, slag inclusions and poor fusion. Repeat this lesson until satis- factory weld can made. Multiple Spot Welders Speed Production increased application Stran-Steel members for building and light construc- tion purposes has led the de- velopment welding machines the Progres- sive Welder Co., 3017 East Outer Drive, Detroit. These machines, capable combined production 2400 lineal ft. steel members, were recently placed operation the Jackson plant the Stran- Steel Corp. Previously riveted and later spot welded means single spot machine, the entire line Stran- Steel joists, studs, half studs, and narrow studs light gage copper bearing steel first formed into angles channels and joined provide nailing space along the entire length each member. The projection formed bubbles stamped regular inter- vals along one half the com- pleted section provides this nailing Two identical machines each em- ploying vertically opposed slid- ing contact guns and six welding transformers (one for each spot weld made) are used. air- hydraulic booster with reservoir and high pressure capac- ity supplies sufficient pressure for the simultaneous operation the guns. accommodate any the vari- ous width Stran-Steel members, provision made for adjustment distance between guns each Guns may moved also for the proper spacing between spots longitudinally. This together with the provision made for cutting out the guns either side (permitting the machine used for welding the half stud members) makes each capable welding any the Stran-Steel sections. IRON AGE, March 27, 1941 Since the different metal require different welding pressure, weld time, and welding current, provision for adjustment each made. Sizes handled vary from about and in. web width in. for the joist. Half studs, made two angle sections and welded with one set guns only, are about in. overall web width. One set small rolls mounted inside the two rows guns sup- ports the work midway between the upper and lower welding points. These rolls also serve locate the position the spot welds which are made through each bubble the member. Another set rolls positions the work laterally. When the work placed the welding machine, the section hav- ing the bubbles the under side. the part moved through the machine, these bubbles drop onto the rolls thus positioning the work for welding. Assembly the sections prepara- tory welding done the welder’s helper who places the an- gles (in the case the joists) position and clamps them. The clamped assembly, usually mea- suring some ft. length, then started through the welding machine. The section pushed through until the first bubble each side the section posi- tion the first welding gun sta- tion, weld made and the clamps removed. sliding contact guns short-coupled with six transformers mounted the base and sides the machine. | TOTAL 2400 lineal feet Stran-Steel framing members per hour can spot welded with this machine which employs twelve vertically opposed pot sed “Book” Molding Wit! Green Sand Cores method core halves not new, and rule this process has been used fairly simple types foundry work. adopt this system molding motor frame castings with intricate coring and successfully production basis, however, real accomplishment.—Editor. HEN General Electric Co. set about develop its new line Tri-Clad polyphase induction motors, one the prob- lems was design frame casting having maximum strength, mini- mum weight, adequate protection for the motor winding, means for supporting the stator punchings, suitable air passages for ventilat- ing the motor and pleasing ap- ECTION the new G-E Tri-Clad motor frame, showing the relatively thin sections successfully employed for the outer shell. BALLARD Foundry Superintendent, River Works, General Electric Co., Lynn, Mass. ° ° pearance along modern, cut lines. obtain gray iron casting maximum strength with economy material simple form, was ETAL core equipment used the booking process. The boxes are split the hor- izontal center line and are hinged the side that after molding completed the two halves may folded into each other, simulating the action clos- ing opened book. decided make the frames with circular flanges around the ends and cross bars between the flanges for supporting the punchings. give suitable air passages holes are needed through the cross bars spaces behind the bars. For min- imum weight, the outer section thickness had held mini- mum and concentricity held within small limits. Protection and pleas- ing appearance called for smooth outer shell with the parting line vertical plane the middle the casting its operating posi- tion. molding, this parting line horizontal plane since the motor frame cast end. addi- tion, the feet required special treat- ment insure adequate strength and good appearance. the early stages the design the foundry engineers were called was obvious that some in- novations casting practices would required the specifica- tions were met economi- cal cost. Cons