The Iron Age 1942-04-02: Vol 149 Iss 14

2,000 Feet Neck isn’t thats being rolled today It’s armament—the tools Victory— airplanes, warships. must keep rolling. Every production win for the enemy. endurance ride the rolls when speed, Bearings are the roll Millions tons rolled the lowest cost per ton ever known prove it. THE TIMKEN ROLLER CANTO TRADE- MARK PAT. OFF. TAPERED BEARINGS : 1942 J ONLY Let’s face the facts. desperate need war The turret lathe key tool the production materials. Warner and Swasey working three shifts, night and day, turn out new turret lathes. 1942 will deliver times any normal year. Yet the combined turret lathe manufacturers falls far short the need. There can only one solution! Turret lathes now the hands pa- triotic operators must produce more. Toward this end, our twenty-one salesmen are instructed subordi- nate sales effort and offer their knowledge and experience war plants help find ways and means making a// machine tools— everywhere—more productive. — APRIL 1942 VOL. 149, NO. VAN DEVENTER President and Editor BAUR Vice-President and General Manager ° Managing Editor, LIPPERT News Markets Editor, ROWAN Technical Editor, OLIVER Associate Editors JAMES Art Editor, WINTERS Editorial Assistants Washington Editor MOFFETT Resident District Editors CAMPBELL HERMAN KLEIN Pittsburgh Chicago Cleveland Detroit CHARLES POST San Francisco terial Editorial Correspondents Buffalo Cincinnati FRAZAR RAYMOND KAY Boston Los Angeles are HUGH SHARP JOHN McCUNE Milwaukee Birmingham SANDERSON ROY EDMONDS Toronto, Ontario St. Louis Seattle ° ° DIX, Manager Reader Service ° ° ° Advertising Staff Herman, Chilton Bldg., Philadelphia Hottenstein, 1012 Otis Bldg., Chicago Raymond Kay, 2420 Cheremoya Ave., Los Angeles, Cal. Leonard, 100 East 42nd New York Peirce Lewis, 7310 Woodward Ave., Detroit Ober, 100 East 42nd New York Johnson, Market Research Mgr. Hayes, Production Manager. Baur, Typography and Layout. ° Member, Audit Bureau Circulation Member, Associated Business Papers Indexed the Industrial Arts Index. Pub- lished every Thursday. Subscription Price North America, South America and Possessions, $8; Foreign, year. Single copy, cents. ° ° ° Owned and Published CHILTON COMPANY Executive Editorial and Offices Advertising Offices Chestnut and Sts. 100 42nd St. Philadelphia, Pa. New York, U.S.A. OFFICERS AND DIRECTORS MUSSELMAN, President JOS. HILDRETH, Vice-President GEORGE GRIFFITHS, Vice-President EVERIT TERHUNE, Vice-President VAN DEVENTER, Vice-President BAUR, Vice-President WILLIAM BARBER, Treasurer JOHN BLAIR MOFFETT, Secretary JULIAN CHASE, THOMAS KANE, HARRY DUFFY CHARLES HEALE This Week in... Editorial Technical Articles Eliminating Drop Hammer Eye Protection for Welders ...................... Stainless Steel Arc Welding New Machine Tools....................... American Society Tool Engineers Features News and Markets Personals and Obituaries 122 Machine Tool Activity Iron and Steel Scrap Copyright, 1942, by Chilton Company (!nc.) f against FIRE, ond TROUBLE and Roofs Rigid, Ribbed Steel the architect, builder, executive charged with the responsibility construction, Mahon Steel Roof Deck warrants special consideration. can installed immedi- ately the Structural has been erected. Work the building beneath Proceeds without provides permanen? protection against fire—weather—ond trouble. can with remarkable speed. ference interruptio n. Mahon Deck simple assembly standard plates, quickly and easily fitted together and into integral whole with the stee! structure which supports it, insuring permanent strength and rigid- ity. Both plant and equipment are protected roof that virtually solid ynit rigid, ribbed steel. Hundreds industrial plants acress the country protected Steel Roof Deck, Mahon Roof Deck. planred for hundreds more. Write for the ing Steel Doors, Shutters and Grilles; NEW catalog—or see you'll understand why. Doors, Doors, Cast Representatives Principal Cities 42—THE IRON AGE, April 1942 | | | APRIL 1942 ° ESTABLISHED 1855 Salesmen Wanted sell this war the American public that not yet aware that business usual, life usual, out for the duration. sell American labor, that the per cent our workers who are liberty loving, not more so, than any other segment our people, will throw off the shackles the power-seeking racketeers who have become their self-appointed leaders and who are bringing disgrace labor whole holding back production when their enlisted brothers and sons are pouring out their lifeblood. sell American employers. the per cent American employers who are willing set their profit limit six per cent, nothing, the Government decrees, and who are disgraced and dis- credited the few chiseling profiteers pay fat stenographers $40,000 year reduce their corporate taxes. sell our legislators. the public spirited and patriotic con- gressmen Washington who will submerge self and section the wholehearted endeavor win this war, not for labor the farmer alone, but for 130 million fellow citizens. What sales campaign that would be! But who today, aside from occasional voice from Washington, selling the war America. Who, for example, undertaking sell the same skilled and thorough fashion that has sold millions motor cars and radios and telephones and other mass production products millions people? Certainly the propaganda mills not doing this selling job. They are busy selling the Department Agriculture farmers; the Department Commerce business men and the Depart- ment Labor labor. They are not selling this war John Public. And they are not fitted it. There are men and women who could. The same men and women who have successfully built mass production America creating demand for the millions automobiles and refrigerators and radios and telephones millions people. These men and women know selling from the ground up; they are experts influencing the desires and opinions vast numbers people. They are the recognized advertising agencies this country, many which are now curtailing their personnel because the fact that there are longer automobiles refrigerators radios typewriters sold. They are the skilled salesmen the companies making these mass production goods who are stopping their selling for the duration. What job these professional experts could for Uncle Sam selling this war America! Why not close, for the duration, the politically manned propaganda mills that are marketing non-essential bureau- cratic services special interests and use the millions thereby released for employing expert salesmen and sales agencies sell the war America? job that challenges and necessitates the best talent have this country. 7 | ia 7 d | q i | | 7 t . ° ° i | | | | | i a Stress cracking overcome the above refrigerator door pan mounting both the draw and trim dies the same press, cutting seconds the lapsed time between draw and trim. How Prevent Stress Cracking Losses due “spontaneous” cracking severely drawn, cold worked mild steel and iron are troublesome, particularly now when maximum war production demands economy steel and the greatest possible number usable parts made the shortest possible time. Cracking, splitting, occurs after the draw operation, often when the parts are finished and placed stock. The causes failure are the severe strains the metal and age harden- ing resulting from cold working. Work harden- ing corner draws has been known increase hardness from Rockwell B-40 the blank Rockwell B-81 one particular type pan. prevent stress cracking, start with steel SHEETS STRIP TIN PLATE BARS RAILS PLATES FLOOR PLATE TRACK ACCESSSORIES suitable for the job. Avoid extreme changes temperature, such storage parts cold areas. equipment available, relieve stresses annealing soon after the drawing operation, trim immediately after drawing before the metal age-hardens and loses much its duc- tility. Cracking has been eliminated reduc- ing the lapsed time between draw and trim from hours seconds. some instances draw dies and trim dies can assembled the same press thereby cutting lapsed time the minimum permitting draw and trim each press stroke. Inland metallurgists have helped many manu- facturers use steel economically speed war production. They are ready help you. STRUCTURALS PILING REINFORCING BARS | 4 | } Dearborn Street, Offices: Milwaukee, Detroit, St. Paul, St. Louis, Kansas City, New ° ° GEORGE WALKER Consulting Engineer, Detroit ° ° ° value and use macro- etching metallurgical in- vestigations does not seem have been appreciated many metallurgists, and instructors technical schools frequently over- look important part the procedure methods for carrying out metallurgical investigations. the examination bar stock, forg- ed, and finished parts, not only quality and defects can deter- mined deep etching, but also the time required for gation greatly reduced. Deep etching many cases serves valuable preliminary procedure when further investiga- tion necessary desirable, and often great value investi- gating causes failures. the case broken and unduly strained parts, the location the begin- ning failure and its progress un- til completed can determined with considerable accuracy. The lo- cation the stressed section where failure most likely occur can also definitely determined careful deep etching. The quality many small parts bolts, nuts, rivets, etc., can quite readily determined suit- able deep etching. Defects Deep Etching Some advantages deep macro-etching metal- lurgical investigations are described herein. The author points out that more extensive use the method can employed investigating the causes failures metal parts. forged and pressed parts, laps, seams, cold shuts, inclusions be- cause dirty steel can quite readily found deep etching, areas stamped parts located. considering the value macro-etching relation micro- scopical investigation, should noted that microscopical examina- tion necessarily restricted small areas. There quite gen- erally physical and chemical non- uniformity all metal parts, some cases being very marked regards grain size, inclusions and segregated areas. Deep etching, however, reveals relatively large areas short time and fairly accurate opinion can obtained the uniformity, location segregated areas, decarburized areas, slag and oxide inclusions, gas pockets, dendritic areas, etc. This information could only ob- tained making numerous speci- mens and rather prolonged micro- scopical examination. After deep etching, any desired area can readily sectioned and examined microscopically for further and more detailed information. carrying out deep etching op- erations, suitably enclosed place should provided, having con- venient accessibility. The floor, walls and hood should well coat- with asphaltum any other acid resisting paint. The floor should slope toward center open- ing provided with grill and con- nected the drain sever that the interior can easily washed down and spent acid solutions emp- tied. The hood should connect- good fan ventilating system provide sufficient forced draft. the center the floor, gas hot- plate, large enough readily ac- commodate two 3-gal. crocks should placed. sink, with hot and cold running water, should placed beside the deep etch chamber, and air blast, tongs various sizes, rubber gloves, beaker and platers brushes should provided. ex- perimenting with various crocks breakage and resistance acids, the best results were obtained with 3-gal. crock marked “Hall-Bam- Marie” and used generally lunch rooms. For most purposes solution 1:1 C.P. hydrochloric acid was satisfactory. parts bolts, rivets, valves, etc., pyrex beakers can used and for larger parts, such steering arms, steering knuckles, gears, sections bar stock, the crock re- quired. deep etching, the acid solution THE IRON AGE, April 1942—45 i ¢ 4 ° ° ° 4 ° ° ° ‘ a ; q i r ABOVE inclusions are shown deep etching the center these bar stock cross-sections. RIGHT 2—This 1045 crank stock shows extremely dirty center, numerous rounded areas due liquidation, segregation, and impurities, and seamy surface. should heated between 176 and 195 deg. before placing the part etched into it. Any grease oil should removed from the part with suitable solvent and loose scale removed with plater’s brush. The time required for etching de- pends the purpose the exami- nation and the nature the mate- rial examined, which many cases can only determined experiment each case depending the care, skill and experience the operator. Some times only few seconds are required develop the structure while other cases re- quire several hours. examining cross-sections 4-in. S.A.E. 4615 bar steel, was found that hr. was required develop sur- face that showed defects laps, seams, blow holes, rimming, and inclusions, the best advantage. examining heat treated ring gears for grain flow relation broken teeth, was found that nearly hr. was necessary de- velop distinct grain flow. The gear, course, was annealed, the back gear machined off remove the case and the machined marks before etching. Forgings generally can etched show grain flow from min. Carbon steels require less time than alloy steels, rivets and sheet steel require only short time, some cases from min. render visible defects laps, rimming, seams, and show whether the threads are rolled cut. instances broken parts, care must taken not over-etch. When necessary they should properly sectioned, and their surfaces ground prepared using emery paper. Fatigue failures axles, steering knuckles, etc., require careful etching de- 3—Here, macro-etching shows two pieces S.A.E. 1045 steel crank stock, etched hydrochloric acid solution. The dark areas the centers indicate high carbon, and pits are the result oxide inclusions. 46—THE IRON AGE, April 1942 velop the progressive steps the fracture from the beginning the failure the final break and the relation failure laps, seams, cold-shuts, cross grinding, etc. Be- fore sectioning part, its relation the purpose the examination should studied that may sectioned the best advantage. power saw should used cut the bar stock, forgings, annealed parts, and hardened parts can readily cut carborundum cut- off wheel, the part being cooled small water jet. Small parts such small bolts, rivets, can placed small clamp and thus readily held against the grinding wheel preparing the surface for etching. The clamp more satis- factory when provided with Allen screws, which have hexagonal re- cessed head and are turned small hexagonal wrench that fits into the recess the head. After sectioning sawing, the surfaces are ground remove the lines caused sawing. medium grain-grinding wheel, No. grain, satisfactory most cases, and the part kept cool being dipped into water. After the part suitably etched, should washed thoroughly hot water, being rubbed the same time with plater’s brush remove any acid solution from folds, laps, etc. The part should then dried once air blast and examined good light. protect the surface further, can brushed over with drafts- man’s lacquer after careful drying. Some additional methods have been developed for certain investi- 4 a | i j 4 q q | | 7 gations and are use specific cases. Deep etching with concen- trated hydrochloric soft spots carburized steel white areas dark surface, shown the Bureau Standards Progress Report, 1925. Waring and Hofammann give the following solution for deep etching forgings: parts hydrochloric acid parts acid part water Time required, about hr. Another solution rather common- used Heyn’s reagent, solu- tion composed of: gm. copper ammonium chloride 100 gm. water The roughly polished sample immersed the solution polished side up. Care must taken that the solution quickly covers the sur- face, and the solution gently agi- tated. coating spongy copper forms over the surface and re- moved with swab wet cotton. High carbon, sulphur phorus areas will darken result the etching. This method use- ful showing segregations and does not require well polished surface. Sulphur prints are frequently useful macro-examination for segregations and non-uniformity. Photographic paper, Azo. No. tion sulphuric acid. The paper film placed side glass plate and the polished surface the steel sample pressed gently against the surface the paper, being careful that does not slip, then remove about sec. The print then washed water and fixed acid hypo-bath the usual manner. Sulphide areas the steel are indicated brown spots the print. course, making sulphur prints requires the use dark room. general, the foregoing meth- ods and solutions have been found satisfactory for most macro-exami- nations. Other methods and solu- tions have been developed for spe- cial steels, such high chromium steels. Good results were obtained with per cent sulphuric acid, per cent bromine solution. Sam- mium steel were min. temperature between 122 140 deg. F., A.S.T.M., 1929. Similarly various etching reagents and methods have been developed for the macro-ex- amination non-ferrous alloys, 4—A transverse and longitudinal section 1135 steel deep etched. those copper and aluminum. However, these will not con- sidered here. Before proceeding the discus- sion results obtained macro- etching shown the following macrographs, desirable con- sider some detail the nature the etching process. stated the beginning, macro-etching valuable preliminary ac- companying the microscopical ex- amination metals, their alloys and metal parts. deep-etching relatively large areas can sub- formity, segregated areas, seams, laps and inclusions. preparing sample for examination sec- RIGHT 5—The end forged crankshaft, split the flash forging. This S.A.E. 1045 deep etched. BELOW 6—A cross-section ring gear forging upset from in. round cor- nered square S.A.E. 4615 steel. tioning and grinding, apparent that the metal the ground sur- face flowed and stressed some extent. The first effect the etch- ing solution the removal the stressed surface, chiefly the boundaries, thus exposing the crystalline structure the surface. the etching proceeds, the grain boundaries are widened and deep- ened, and the stressed surface within the grains where rela- tively thin, removed. more detailed consideration the nature and mechanism the etching process considerable interest and importance. Why does the etching solution attack the grain boundaries more vigorously THE IRON AGE, April 1942—47 : ! q q t yr ABOVE 7—Cross-sections ring gear blanks, S.A.E. 4615 steel. The top specimen was forged hammer and the lower was forged press. BELOW grain flow produced this connecting rod bolt produced up- setting. The head symmetrical sides and around corners, and showed rup- tures. S.A.E. 1115 steel. 48—THE IRON AGE, April 1942 RIGHT The crank end connecting rod and cap, show- ing 1035 steel. BELOW crankshaft forging, S.A.E. 1045 steel. \ \ \ | / / \ \ \ \ \ \ W / / / / | \ \ \ \ ; \ \\ ABOVE line across the head the bolt shown Fig. shows the point greatest curvature the grain flow, and forms symmetrical elliptical area. RIGHT 12—The head this cylinder head bolt was cyanided. Physical tests showed strength 95,250 per sq. in., and ultimate strength 107,750 sq. in. steel. | Sa — 7 than the other parts the sur- Why some metallographic structures corrode than others, and what the effect alloying elements and inclusions revealing the structure etch- ing? The instability the atomic structure the surface the grains believed considerably accelerate the etching the boun- daries. also probable that finely dispersed inclusions, such oxides, which are rejected toward the boundaries the grains during the cooling and crystallization the metal, may have marked ef- fect the rapidity etching.* See “The Importance Boundary At- tack the Etching Steel Specimens,” American Society for Metals, Dec., 1937. When etching finished, the areas low carbon appear light color compared with those higher carbon content. Areas low carbon appear quite light, and decarburized areas nearly white color. Slag inclusions the fusible silicate type appear but slight- attacked and stand out white, sharply defined areas, surrounded somewhat dark area ap- metal. Inclusions the oxide type appear dark, nearly black, some- what irregular These areas, relatively small, occur irregular and isolated groups and are found more frequently to- ward the surface the cross-sec- tion bar stock; while the fusible silicate inclusions are found more frequently near the center. This appearance shown the macrograph, Fig. which shows cross-sections bar stock having white silicate inclusions the cen- ter. The large cross-section shows rather large segregated center, the darker appearance indicating somewhat higher carbon content The small areas ad- jacent the inclusions are also darker than the adjacent metal, evidently due more rapid etch- ing adjacent the inclusions and little higher carbon content which rather mark- ed. Fig. shows the macrograph S.A.E. 1045 steel crank stock. This steel shows numerous large, round- segregations relatively high carbon content and number in- clusions the oxide type. The numerous thread like inclusions the surface were evidently formed the pressures the surface during rolling. the center, the black area composed almost en- tirely graphite. The ingot from which this bar was rolled was cropped too near the top and was probably poured from dirty melt. This macrograph shows the im- portance sampling and deep-etch- ing insure good quality steel. macrograph two cross-sec- riage bolt macro- etched. S.A.E. 1112 steel. IG. cross- sections through the heads hexa- gon headed bolts. steel. tions crank stock etched 1:1 hydrochloric acid solution for min. temperature 185 deg. plain carbon steels etch more rapid- than alloy steels. will noted that this and the preceding macrograph the lines marks caused grinding the surfaces are longer apparent. The etch- ing generally continued the point where the marks left grinding are longer evident. The section the left shows appear- ance quite similar that shown Fig. but the variation car- bon content more marked. The section the right fairly good structure except that shows rather high carbon content the center. Also the center shows some marked pits the nature rather typical oxide inclusions. The other parts the cross-section show rela- tively small and fairly well dis- tributed inclusions. Fig. shows two macrographs THE IRON AGE, April 1942—49 SS 4 | | q f | _ Fig. etched hood catch bolts S.A.E. 1010 steel. longitudinal and cross-sections bar S.A.E. 1135 steel. The center the cross-section shows somewhat lighter coarser grained structure than the sur- face area. This also shown the longitudinal section which shows longitudinal segregated bands the inner two-thirds the section. cross-section shows number irregular groups inclusions and near the sur- face area, such inclusions being more frequently found near the sur- face. One area the surface and free from inclusions and the longi- tudinal section was evidently cut through such area. Fig. shows macrograph the cross-section forged end crankshaft, S.A.E. steel, which split along the flash when forged. The bar from which was forged had dirty center similar that shown Fig. the left. When the bar was forged and the metal forced out between the dies, the central dirty section was flat- tened and extended the surface, forming band across the section and extending into the flash. When the flash was trimmed off, ruptures were formed due inclusions and seamy condition the steel caused them. often desirable know the direction and nature the grain flow certain parts relation the design the part and the method forging. Grain flow can readily determined sectioning and deep etching, this applying hot forged well parts. working the steel whether pressing forging with drop- hammer, the grains the steel are elongated the direction flow, that when the section suitably etched, the direction flow readily determined macroscopically shown macrograph, Fig. This shows the cross-section ring-gear blank forged with steam hammer, the thinner part the section being the inner part the ring. This part, being more heavily worked, shows the most marked grain flow extending into and nearly across the large section IG. 17—This 3140 steel truck axle failed after 1050 miles, in. from the spline end. The transverse cracks indicate grinding marks. The fracture started the grinding marks where the surface was scored and stressed, and progressed until complete failure occurred. 50—THE IRON AGE, April 1942 coarse grained center and parallel transverse lines extending toward the center this hammer rod indicate the location and progress the fatigue frac- ture, and upward toward the tooth sec- tion. This section shows only few and relatively small oxide type inclusions. macrograph similar sections S.A.E. 4615 steel ring gear blanks shown Fig. No. shows the grain flow forged under hammer and No. shows blank formed press. The grain flow much more marked No. Fig. shows longitudinal section through one throw S.A.E. 1045 steel crank- shaft. The desirable grain flow follows the contour the shaft fairly closely. Fig. shows macrograph the grain flow the blank, forged from S.A.E. 1035 steel. The flow quite symmetri- cal the sides, but the end somewhat transverse. This satisfactory forging insofar grain flow concerned and shows laps, ruptures marked inclu- sions. Deep etching provides and dependable method for the ex- amination bolts and rivets. fact, large number bolts, more, can etched one time, thus increasing the range and reliability the examination. Fig. shows macrograph the grain flow the head fairly good cold-upset bolt. The flow symmetrical across the head and there are abrupt changes the direction flow, laps folds under the head, and the corners ‘ 3 ~ 4 J ° ° ° | | | i | ; q under the head are fairly well rounded. line drawn across the head points maximum curvature the flow lines, forms quite uniform, elliptical curve, shown Fig. 11. The longitudinal section through the head cylinder head bolt shown Fig. 12. The grain flow more irregular than that shown Fig. 10, the corners under the head are rather sharp, and the central part the head shows marked carbon segregation. Fig. shows macrograph the lon- gitudinal section through head S.A.E. 112 steel carriage bolt. The grain flow more irregular than that shown Fig. and also seen that ruptures the head follow the seams the seamy stock used making sections through heads cold-up- set hexagon headed bolts, S.A.E. 112 steel. Nos. and show marked segregated areas, Nos. and show several large in- clusions, No. particular. Fig. shows the three stages the formation hood catch bolt S.A.E. 1010 steel. This macro- shows that the steel rimmed and that the rimmed area lower carbon and coarser grained than the core, general characteristic rimmed steel. Deep etching affords speedy method for the examina- tion the bolt threads. The bolt ground longitudinally along one side little below the threads, and etched. short etch from and the grain flow the threads shows whether they were cut rolled. can also readily seen whether the threads are decarbu- rized which the case when bolts are made from rimmed steel. When rimmed steel used for making bolts, the threads are easily formed rolling because the metal the surface the bar soft, but the threads are easily stripped under tension and such bolt unsatis- factory. Rolled threads, some cases, show laps their sides, the points, both, condition readily shown short deep etch. examining threads and deep etched surfaces, pocket magnifier siderable assistance. Deep etching important de- termining the causes failure metal parts. some cases, careful deep etching reveals the whole story. Fig. shows macrograph the fractured end steam hammer rod which failed service. The fracture started one side and progressed toward the center, the successive steps the failure being observable noting the roughly parallel lines extending across the surfaces the top. The coarse grained center was doubtless contributing factor causing failure. Fig. shows macro- graph failed truck axle-shaft S.A.E. 3140 steel. This axle was forged method which produced flash opposite sides. The flash was removed trimming and the rough, irregular surface left the trimming operation was ground off. grinding transversely the longitudinal axis, fine transverse lines were left the grinding operation which can observed the macrograph. These fine lines formed the beginning fatigue cracks which finally resulted the failure the axle. The fatigue cracks and their relation the grinding marks can plainly seen the macrograph, apparent careful deep etching. Apparatus has been devised for the purpose determining the presence and loca- tion fatigue cracks electro- magnetic analysis, but some cases deep etching has revealed the presence fatigue cracks not found magnetic analysis. This discussion macro-etching means exhaustive, but indi- cates that much more extensive use can made than com- monly employed. Also, macro-etch- ing considerable value in- vestigating the causes failure metal parts and examining in- coming stock its uniformity and freedom from defects. Metal Heater Speeds Machine Gun Production present emergency bringing out new uses for al- ready established products. Accord- ing American Car Foundry Co., the Type electric metal heater, shown the accompanying photo, now being used the selective -hardening and annealing many the small parts used the cal. Browning machine gun. Some the advantages specifi- cally claimed this new use are: Savings direct labor; more con- sistent results; elimination the necessity for successive cleaning the parts remove lead, etc.; the provision for larger amount additional heat treating capacity relatively small space; and quick electric heat localized the section, thus speeding produc- tion. THE IRON AGE, April _ a ss. ik- aft ° MACHU Vienna Reclaiming Plated Metals arated from the parent metal. This segregation can also effected quenching the hot charge water. The separation copper, nickel, and their alloys scrap can effected, according Various methods, chemical and electrochemical, re- claiming plated metals are discussed this review American, German, Austrian, Swiss, English and French patent literature. Platings covered include copper, nickel, zinc, tin, silver, gold, platinum, rhodium, lead, 292, antimony and aluminum. French Pat. 460,322; 1913), the action ammoniacal am- — growing practice plat- ing ferrous materials with layer corrosion resisting metal developing new source valuable scrap metal. com- prehensive discussion the processes which may applied exists, the best the author’s knowledge. fill this void, this review presented, covering pat- ent literature which has appeared Germany, Austria, Switzerland, England, France and America. Processes not immediately con- cerned with the recovery plated metal, but which can used for such purposes, have been included this review. However, processes for the recovery tin zinc are not covered since these coatings are not usually applied plating. The techniques discussed here broadly divided into two classes— chemical and electrochemical. Chemical Processes One the oldest proposals for the removal plating sheets comes from Leitmann (DRP 54, 227; 1890). The plated scrap heated air other oxidizing medium, such water vapor, order effect oxidation the 52—THE IRON AGE, April 1942 coating. cooling air, water quenching using mechanical treatment, such tumbling hammering the oxidized layer removed. According process developed Heltmann (DRP 67, 178; 1893) nickel copper-nickel plated scrap sheets are heated red heat and sulphur added the amount necessary for the formation sulphite. The retort kept air-tight and the metal heated thoroughly. The sulphur combines with the metal and the nickel nickel-copper layer can removed after cooling hammering. stracted from article appearing Korr. Metallisch, Vol. 1941, 70. Very similar the process Hirsch, Kupfer and Messing Werke, A.G., and Grot- thus, Eberswalde (DRP 321, 525; 1920), for the removal copper plating iron. This process con- sists packing the scrap, mixed with calcium sulphite, iron boxes and heating reverbatory muffle furnace. After thorough heating the material removed from the furnace and cooled. The scrap then put into ball mill and the copper sulphite layer sep- monium carbonate solution, with the assistance air. From the copper-bearing solution the metal can recovered the form copper hydroxide basic copper carbonate the distillation the ammonia. copper nickel plated sheets are treated, the cop- per, and subsequently, the nickel, can precipitated from the am- moniacal solution the addition zinc-covered iron scrap. Copper-Nickel Recovery According further develop- ment this process (DRP 293,- 140; 1917) copper nickel can recovered the action the ammoniacal ammonium carbonate solution and adjustment the air supply such fashion that the base will always precipitate finely dispersed copper when the alkaline solution acidified. This reduces ammonia losses. Copper and the copper-nickel sheets can also salvaged process Koelsch Nuremberg (DRP 330,131; 1920) using solu- tions which nitrite ions are excess and H-ions (acetic acid) are lower concentration. these solutions the iron passive and therefore not attacked, while the copper and nickel are easily dis- solved. Nickel plating sheets with | ‘ | | | | | q | q q alternate layers copper and nickel can recovered, according Hagen (DRP 464,579; 1928), the copper treated aqueous solution ferric salts, such ferric sulphate which does not con- tain either free acid halogens. these solutions the nickel oxygen peroxide compounds, such persulphuric acid salts, the solution the copper can ac- celerated. The use oxygen car- riers acts further hasten the so- lution. Silver and rhodium layers can removed from silver-plated parts which carry outer cover rhodium intermediate cover nickel, according sug- gestion Baker Co., Newark, (DRP 632,382; 1936; Brit. Pat. 459,130; 1937; French Pat. 791,298; 1935; Pat. 2,057,271; 2,057,272; 1936). This can ac- complished using aqueous solution phosphoric hydro- two, containing also sodium chlo- ride, aluminum sulphite and acetic acid. This dissolves only. For the removal tin, lead, antimony aluminum ing Spitz Bruenn (Austrian Pat. 43,468) suggests aqueous solution sodium hydroxide. For the removal copper, silver gold plating suggests aque- ous potassium above 100 deg. and under pres- Kochs Dusseldorf (Austrian Pat. 59,925; 1913) plated scrap treated with compressed air rotating, perforated, direct heated container. The air led away through the hollow perforated axis the rotating container, carrying with the loosened pieces the coating oxides and impurities. Gun Barrel Plating Copper deposited the interior gun barrels during firing can removed, according Soc. Metallisation Paris (Swiss Pat. 90,976), treating with low melting alloy per cent zinc and per cent lead. This forms low melting alloy with copper. However, after this layer lead bearing alloy formed the barrel. remove copper nickel plat- ing, Hodgkinson Kent, England (Brit. Pat. 3,225; 1905), saturated with urea which contains per cent ammonia and 0.1 per cent copper nickel chloride. An- other solution for the removal copper nickel suggested this patent consists ammonium for- miate, ammonia, and copper chlo- ride, and another one ammoniacal solution ammonium persulphate. The patent Alexander Newcastle-on-Tyne (Brit. Pat. 126,377; 1919), pri- marily concerned with the recovery tin from tinned products, but mentions also the recovery an- timony, lead, aluminum, and copper. His process consists heating the plated metals the presence reducing gases above the melting point the plating. The molten metal required flow through tunnel over incan- descent coke. Lead plating can removed, ac- cording the Dudzeele Corp. Delaware (Brit. Pat., 343,793; 1931; Pat. 1,886,411; 1932) use dilute sulphuric acid containing sodium chloride and, accelerator, nickel sulphate nickel chloride and possibly plat- inum chloride. Very similar the proposal Dudzeele Paris (Brit. Pat. 345,107; 1931; Pat. 817; 1933) which the removal acid sodium nitrate bearing solu- tion ferric chloride, acid solution sodium chloride and sodium nitrate. solution sodium nitrate containing per cent sulphuric acid also sug- gested. The best results, however, are said obtained with per cent sulphuric acid, solu- tions containing per cent sodium bi-sulphate, per cent sodium nitrate and per cent sodium acetate. These solutions should saturated with sodium chloride. Lead plating can also removed Bowman Ohio (Masne Assigne- ments, Pat. 1,785,245; 1930) oxidation the lead fused sodium nitrate, peroxide chlo- rate between 260 and 538 deg. (500 and 1032 deg. F.) and solu- tion the lead oxide the per cent hydrochloric acid containing thio-urea prevent the acid at- tacking the iron steel. leeches copper, tin, lead, zinc- bearing metal scrap with nitric acid the presence air. The meta-tin acid allowed settle out while the copper precipitated the cathode and the lead the anode. Electrolytic Recovery According Roeder Ber- lin (DRP 100,975; 1898), plated copper, nickel, their alloys, can removed from iron steel anodic treatment solution sodium nitrate. the same end, 102,646; 1899) applies aqueous solution ammonium carbonate. Copper nickel are deposited the iron cathodes. Others have pro- posed ammoniacal solution ammonium acetate (Kings Norton Metal Co. England, French Pat. 387,917; 1908; Brit. Pat. 717; 1906) ammoniacal solution ammonium sulphate (M. Wurmbach, Brit. Pat. 21,052; 1911; 21,512; 1911) electrolyte for the removal copper, nickel, their alloys. plating silver, nickel, gold can recovered the action sulphuric acid (s.g. 1.53), pos- sibly with the addition hydro- chloric acid chloride (E. Harbeck, 189,876; 1907). The identical electrolyte was sug- gested Levy (Brit. Pat. from copper, brass iron. Nickel plating can also removed from iron steel parts the use acid. arrangement for the electro- lytic removal plating also put forward Ruthner (Aus- trian Pat. 155,214; 1938) which the material fed uninterruptedly through electrolyte which does not attack the base metal. The electrolyte kept continuously agitated drum. The axis the rotating drum, which carries feed-guides screws, inclined towards the horizontal. the lower opening conveying arrange- ment attached which carries away the base material after its separation from the plating. Platinum plating, which, usually can removed anodic treat- ment fused potassium and dium cyanide (R. Atkinson, London, Pat. 2,093,406; 1937). THE IRON AGE, April 1is er. el, er, the ith the tal per the kel op- ion lop- the air the This hese and the dis- with 7 theory vibration and impact has been well in- vestigated recent years machines, such drop power hammers, can now effectively isolated, and their thud and vibration localized and reduced that objections their proximity are overcome. The essential feature this correction stabilizing concrete foundation supported above its center grav- ity groups helical springs proper resilience. The deflection from impact thereby lowered springs alone, and the coils absorb the energy the moving hammer and block without transmitting the pulsations the surrounding area. The moving mass has time vi- brate its own particular rate and come rest between hammer blows. The concussions from hammer operating near the boun- dary factory property Ham- ilton, Ontario, gave rise seri- ous complaint from the staff neighboring office. The problem isolating the vibration the ma- chine was submitted the Korfund Co., Inc., Long Island City, Y., who worked out means curing the trouble design embodying special mountings for the hammer. The offending hammer was or- dinary belt driven board-drop type, rated 2000 but had over- size ram 2500 The machine weighed 53,000 including its an- vil base 30,000 and stood unbolted maple planks be- low floor line recess concrete foundation block 10x10x10 ft. The pull the open and crossed belts that drive the two 48x9 in. pulleys height ft. was counter- acted two inclined tween rear lugs the hammer head and countershaft superstruc- ture the roof truss level near the wall. From the operator’s view- point, the hammer was perfectly satisfactory, operating with upper dies weighing much 1400 and dropping maximum in. the rate one blow per sec. 54—THE IRON AGE, April 1942 ting comply with the recommenda- tions for stopping the vibrations from the hammer, entirely new foundation The laborious task removing the old block was avoided finding new site for the hammer alongside the old. hole was excavated form concrete pit enclosure 16x14x12 ft., with recess hold new con- crete inertia block 9x9x10 ft. This was ultimately float springs mounted near the top, with 2-in. clearance all four sides and 2-in. clearance below when the up- per surface the block was floor level. The 18-in. bottom slab was rein- forced above its neutral axis rods criss-crossed 12-in. centers prevent any upward bulging the middle the slab. the soil held moisture below depth ft., and was important that seepage water allowed fill the air space below the inertia block when suspended, posi- tive drainage was preferred treatment floor and walls the pit. The pit enclosure was shouldered two opposite sides take 15-in. channels the flat, which eight Korfund Vibro-Isolators would later rest and carry the floating load. The concrete walls above this level were strengthened vertical rods extending well shoulders. The 55-ton inertia block was poured into welded tank resting the bottom the pit. The tank was 3/16 in. copper bearing steel rods squarely bent the ends and welded the sides preserve smooth exterior. The rods were spaced far enough apart allow man get down into the tank be- tween them. Four pairs 12-in. channels with welded vertical spacers were set across the top the tank, rest- ing the shoulder channels, and the ends each pair were arranged house the isolator units. maintain solidity within the block, two 18-in. channels the flat were suspended near the bottom four 2-in. tie-rods from similar pair laid across the isolator channels. The square the tanks was ex- tended upwards in. below the floor level wooden forms con- fine the upper part the inertia block. The bottom the anvil recess, 66x41x24 in., was level with the top the isolator channels. Two gaps, in. wide and in. deep, were provided, crossed sides and running out one side the block. They permitted subse- quent removal the spacing tim- bers. Horizontal strips sheet metal set into the pit wall and across the tank kept out debris from the pit during construction. These strips were afterward bent down flush with the concrete walls. stages. After the inertia block had set and the forms were the isolator units were reassembled place within the projecting ends the pairs channels. Each con- sisted nine helical steel springs, in. diameter, nested between upper and lower bearing plates, beneath heavy steel bridge se- curely bolted the reinforced up- per flanges the channels. When unloaded, the springs and upper bearing plate were just clear the lower side the bridge. distribute the weight the anvil, permanent layer in. maple planking was placed the bottom the anvil recess. The an- vil was then carefully moved across the top the concrete and lowered onto two tiers in. planks set the recess and flush with the top. Then, lowering opposite ends inch time, was rocked down its seat two heavy jacks that engaged cored pockets the anvil, and the pack- ing was withdrawn piece piece through the gaps the concrete until finally the anvil stood the maple. The space around the anvil was then filled with mastic as- phalt accommodate any slight sway that might occur. q é | 4 | | f 4 q ~ | 4 q | When the columns parts the hammer were assem- bled the anvil, the hammer and inertia block were raised the eight screws that com- pressed the isolator springs. The airgap around the block its work- ing position was sealed against and floor dirt 4x4-in. strips sponge rubber, held under slight compression between the flanges the concrete. Checkered floor plates covered the channels and projecting rubber, except for gap in. all around the block. After the hammer was raised and the base leveled, the driving belts and rear tie-rods were put on. The belt pull plus the freedom oscillate vertically caused dency for the hammer rock back- wards and forwards the rows springs and communicate vibration the lineshaft super- structure. This was counteracted giving the rear tie-rods little inclination possible, controlling their tension compression springs the ends and stiffening the superstructure diagonals. resuming forging operations, the improvement was easily notice- able the absence jar the floor even short distance away. However, the moving mass vibrated about three times per sec., cal- culated, with normal amplitude about in. The operator was re- Petroleum Base Tinning Oils the Tin Re- search Institute have resulted the development tinning oils derived from petroleum. Used floating layer top the molten tin bath tin plate manufacture, tinning oils heretofore were the palm oil variety, but scarcity this product has forced the development new oils. drop-hammer mounting formance, similar the mounting used Hamilton, Ontario. This installation was made aircraft plant the West Coast. lieved from much this vibration standing with one foot shallow bridge that spanned the pit enclosure, just clear the inertia block, and the other foot the hammer control treadle. For ordinary jobs, like crank- shaft made deep impressions with few blows from upper die falling in., the lay- out was perfect. the case smaller jobs, however, like one forged from square stock and drawn out long and thin shallow impressions with extensive flash, under blows from 560 lb. upper die falling in., oscilla- tions got and out step with the imposed frequency the blows. Eight snubber units, put into place Several suitable have been selected which can used throughout comparatively wide range temperatures and show excellent stability and free- dom from fuming and fire hazard. Each carrier may used combined with choice active agents. Some the oils tested compare favorably with palm oil and tallow, ° ° GEORGE LAIDLER Hamilton, Ontario without lowering the inertia block, cured this trouble. Each consisted 3x3-in. hard rubber cylinder and were confined the ends and free bulge under pressure. Two the nine springs each the Vibro-Isolators were replaced these snubbers. Pressure each snubber was controlled 1-in. screw, threaded into the bridge pier the isolator and extending through clearance hole the spring pressure plate. slight com- pression determined trial was sufficient reduce the amplitude oscillation the hammer and block sufficiently for all types jobs, and without increasing the earth-borne vibrations any ap- preciable extent. Developed especially high temperatures such are met hot tinning, while others have been found useful for covers lead-tin baths. Use cotton seed oil has been reported the United States several tin plate manufacturers, with excellent results. Results further experiments its use will probably forthcoming shortly. THE IRON AGE, April 1942—55 ° ° ° | [ | [ ®.. * . Ss _ e S e e i © e e | | Eye Protection for Arc Welders estimated that sufficient energy automobile. This energy dis- sipated rate equivalent about hp., temperatures the neigh- borhood 9000 deg. quently, enormous amounts ra- diation are emitted the against which welders’ eyes must protected. The nature this radia- tion may generally divided into three classifications: (1) Ultra- violet; (2) visible, and (3) infra- red, their relative position with re- spect wavelength being explained Fig. While ultra-violet visible rays may have harmful effects the eyes, infra-red rays are likely give the most trouble unless guarded against. Ultra-violet rays will cause severe inflammation both the eyes and surrounding tis- sues, similar nature sunburn, and visible rays extreme intensi- ties may cause eyestrain and pro- duce temporary blindness that can result accidents busy weld- ing shop. However, infra-red rays penetrate eye tissues and cause cumulative effect tissue changes possibly resulting cataracts, in- jury the retina, and opacity the cornea and aqueous chamber. From Fig. may observed that the ultra-violet portion the spectrum contains from per cent the total energy content arc radiation, the visible portion con- per cent the radiation con- tained the infra-red portion. Consequently, protective welding lenses must designed eliminate all harmful radiations, both ultra- violet and infra-red, and reduce visible radiations point where glare eliminated and the observa- tion metal deposition and slag formation easy and without eye Most lenses today will af- ford adequate protection against ultra-violet rays and control visible light, but there still problem finding materials that will effec- tively eliminate infra-red radiation. Metallic films less than one wave- length thick have been found re- flect high percentages infra-red radiation, yet allow visible radia- tion pass through them. vestigations Hagen and Rubens the reflective properties pol- ished metal surfaces, shown Table indicate that silver re- 56—THE IRON AGE, April 1942 American Agile Corp., Cleveland ° ° ° markably suited for this purpose, reflecting per cent more all visible light and from per cent the infra-red radiation. careful deposition thin silver film glass suitable char- acteristics with respect the ultra- violet rays and visible light, lens obtained that gives positive protection and excellent, glareless visibility the work with pleas- ant shading color that slightly yellowish-green. proper varia- tions the coloring the glass used, full range standard shades* set the National Bureau Standards produced. Protection afforded any these shades the same, the grading re- ferring only the amount vis- ible light transmitted through the