The Iron Age 1936-06-18: Vol 137 Iss 25

JUNE 18, 1936 engineered, Gears and Gear Reducers— produced completely equipped plant under constant mechanical supervision. 3 ft JAMES MANUFACTURING CO. 1120 WEST MONROE STREET CHICAGO, ILL. ir q > } > ANOTHER RECORD FALLS! Object the admiring gaze thousands, saluted the whistles other craft, the new speed queen the Atlantic warped her pier after record crossing. Praise and congratulations are lavishly given captain and officers. But few gave due credit the members the crew for individual skill and efficiency their appointed jobs. Few visualized, within the sleek hull, the innumerable mechanisms and devices which made movement and control the great bulk For records are made perfection details. small machines and electrical devices there are few—in giant liners there are hundreds—of vital parts that are more reliable, more durable, more sure function when made ELEPHANT BRAND phosphor bronze. Control the integrity ELEPHANT BRAND PHOSPHOR BRONZE THE PHOSPHOR BRONZE SMELTING 2200 WASHINGTON AVENUE INGOTS CASTINGS RODS PHILADELPHIA, 7 \ \ ELE 9 AN BRA NO hé Aaa , BRONZE URE | FRITZ FRANK, President VAN DEVENTER Editor Managing Editor Emeritus Machinery Editor Washington Chicago Cleveland Pittsburgh FRANK OLIVER GERARD FRAZAR McINTosH Detroit Boston Cincinnati CHESTNUT AND 56TH STREETS, PHILADELPHIA, PA. Sales Offices Little and Big Constitutions Better Rails for the Warehouse Industry Makes Progress........ and made rts that unction Copyright 1936 Chilton Company (Inc.) Owned and Published CHILTON COMPANY (Incorporated) BAUR, General Advertising Manager Executive and Publication Offices, & DIX, Manager Reader Service Chestnut and 56th Sts., Philadelphia, Pa. Member, Audit Bureau Circulations ADVERTISING STAFF Member, Associated Business Papers MUSSELMAN, President Emerson Findley, 621 Union Cleveland Indexed in the Industrial Arts Index. B. L. Herman, 675 Delaware Ave.. Puffak Published every Thursday. Subserip- FREDERIC STEVENS, Vice-President Hottenstein. 802 Otis Chicago tion Price: United States and Pos Peirce Lewis. 7310 Woodward Ave., Detroit JOSEPH HILDRETH, sessions, Mexico, Cuba, $6.00; Can Charles Lundberg. Chilton Bldg.. Chestnut & GEORGE H. GRIFFITHS, ie ada, $8.50, including duty; Foreign 56th Sts.. Philadelphia, Pa. : EVERIC B. TERHUNE. ee $12.00 a year. Single copy, 25 cents. C. H. Ober, 239 W 39th St.. New York W. B. Robinson, 428 Park Bldg.. Pittsburgh ERNEST C. HASTINGS, Wg W. C. Sweetser, 239 West 39th St.. New York Cable Address, Warren, Box 81, Hartford, Conn. | WILLIAM A. BARBER, Treasurer JOHN BLAIR MOFFETT, Secretary | ‘ \ | 4 yaa i BR OR BP ONZE ; BETHCOL TRADE MARK BETHLEHEM COLD-REDUCED TIN PLATE \ \ ‘ %% 4 new continuous cold- strip mill for the manufacture tin and black plate now operation. The product this new known Bethcolite. With excellent deep-draw- With this cold-reducing mill, having ing qualities, close gauge tolerances and annual capacity tons, sup- remarkably smooth surface, meets plementing existing facilities Bethlehem rapidly developing need the tin and position meet every requirement black plate consuming industries. tin and black plate users. 24—THE IRON AGE, June 18, 1936 A THE IRON AGE ... JUNE 18, 1936 ESTABLISHED 1855 Vol. 136, No. Little and Big Constitutions some our social theorists and New Dealers could have been Middletown, Ohio, June the occasion they might have learned some- thing about constitution, and what does promote industrial peace. constitution, you know, bill rights which defines the privileges the governed and limits the powers those who govern them. Years ago, George Verity and his associates the American Rolling Mill Co. decided that con- stitution for industrial organization was just essential constitution for liberty prizing people. So, utilizing the best thought management and labor, they made one. The Armco constitution living one, just the Constitution the United States. subject amendment through proper procedure our national Constitution. Each employee has copy it. Twice each year, every Armco worker urged read reread his constitution that may understand his rights and obtain them. That would good idea for Uncle Sam adopt with his citizens. Middletown and its environs have become known its years activity, Armco has never experienced interruption labor trouble. And the monster parade men and women which recently honored the first citizen Middletown, the ranks organized labor paid tribute the chief course, this industrial peace Armco has not come just from having con- stitution. has come from using has been and used, daily, men and management solving the problems which arise lationships. Employees this company are not demanding, seeking from its management. They know that their constitution insures them square deal, which much better and also more definite. protects them from dictatorship and exploitation because not only defines their rights but also limits the powers those who govern their daily activities. Because having learned the value constitution seeing work, the men and women Middletown are better position than most people realize the protective value our great national Constitution. You will not find many among them who would favor its nullification agree with the Washington pro- fessors that should discarded favor dictatorial manifesto. More these little constitutions American industry would promote under- standing and respect for our big Constitution. & ‘ 3 SS ape =" NN ent 2 5 Climax Molybdenum Co. 26—THE IRON AGE, June 18, 1936 odeling the Foundry Describing Unique Use To-Scale Pilot Castings Solve Difficult Production the Scope the X-ray Foundry Tool LIPPERT Metallurgical Editor, The Iron Age SOUND body be- neath Such the hope every foundryman sends along with each ship- ment castings. Quite often the skin his casting envelops sturdy, perfect interior. And quite often the castings perform usefully and satisfactorily for many years, even though there hidden mul- titude shrinkage cracks, blow holes, cracks, inclusions, ete. But much too often these defects show the buyer’s lathe quickly break down service. this lat- ter case, the founder often suffers material loss and the reputation castings dependable product beclouded. The inability founder con- fidently guarantee sound cast- ings has been the main factor contributing the partial eclipse the casting shop during the past decade. Internal qualities rolled forged metals have been more dependable and reproducible; con- sequently these two modes fabri- cation grew favor for certain types work that few years ago castings were the verge being dary position. Many founders have refused recognize this loss face, whereas others did recognize their disad- vantage but did nothing about other than the usual crossing fingers each lot castings was shipped out. But certain more ag- gressive members the foundry industry refused accept semi- oblivion, and this group the science cast metals owes debt gratitude for spectacular renaissance during the past several years. The foundry today again dominant factor the indus- trial scene. can turn out com- plete cast railroad car, paper- thin cast alloy automobile piston, and multitude other products which can compete with other types fabrication either performance basis price basis. Much work has been done the foundry accomplish these ends. The role impurities has become more fully recognized, new types i 7+ q = i —— | | alloys have been developed, heat treating has become dependable art, and molding and melting tech- niques have been revamped. Even that old standby the jobbing foundry, gray iron, has figuratively been given new set glands and now shows physical characteris- tics, surface finish and machining qualities far superior its proto- type several years ago. Foundry Difficulties Despite these vances the founding art, the average plant must still contend with (1) gas, slag and sand pockets due loose dirt the mold, (2) gas cavities due imperfectly de- oxidized metal, (3) sand inclusions due cutting the mold run- ners, (4) pipe primary shrink- age caused failure risers function intended, and (5) sec- ondary shrinkage caused bridg- ing constricted portions the section. This discouraging list what could happen, but, fortunate- ly, most plants have ardized and controlled foundry practice that many these faults are minimized. However, when new job comes into the shop, the founder still has much for worry. His molders must spot gate, scatter few risers around where experience dictates, and, perhaps, tilt the mold this way and that during pouring. The hope that innate ingenuity and past ex- perience has enabled them either entirely shrinkage cavities, flocculent shrink, blow-holes, cracks, and in- clusions, least confine these defects less significant sections. Probably, new job some importance the average founder will cast one more pattern-size pilot castings section them for visual exami- nation perhaps farm them out for radiographic inspection. there concentration defects important section, the usual procedure re-locate gates and risers, after which additional pilot castings are made. Quite num- ber pilot castings are often made and examined before actual pro- duction started new order. But the castings involved should large, obvious that foun- dry cannot very much destruc- the order. One company, however, has pointed way with alternative which could adopted even the smallest plant. When new job comes into the shop, instead ex- perimenting with several pilot cast- ings full-scale the pattern, its to-scale model castings. Optimum molding and casting practices can established and these turn can transferred the full-scale job. much more satisfactory examine these to-scale models radiographically, although small foundry could use destructive test- ing with moderate success. There novelty the use full-size pilot castings, but the ap- models unique. The development this technique opens the way for more extensive experimentation with each production job; for the cost metal and labor very much lower than when full-size pilot tested, and radiographic in- spection can crowded one 17-in. film, compared with multitude exposures limited area for pattern-size casting. Credit for the development the technique pilot casting be- longs Earnshaw Cook, research metallurgist for the American Brake Shoe Foundry Co., and Burtt, radiographer for American Manganese Steel Co., subsidiary. How these men used to-scale models solve particu- larly difficult production problem the primary consideration this article. Using these experi- ences model, any other foun- dry could achieve similar success jobs which are giving trouble. Castings Failed One the routine foundry jobs the Amsco plant Chicago Heights, the casting crusher liners from manganese steel. These liners are used large custom mill equipment for crushing very abrasive ore. The liners are shaped like the frustum hollow cone, and are quite large, measuring ft. across the widest section and weighing the neighborhood 6900 One these liners shown Fig. actual use there smaller liner which fits inside and wabbles eccentric, thereby crushing the ore and separating the fines. cast, the liner wall averaged in. thickness, but after some months service the wail wore down fraction inch. Although many liners gave satis- factory service, the users occasion- ally complained that certain mantles started fail prematurely. This wearing was generally regu- larly distributed around the periph- ery the shell, and was serious enough necessitate scrapping even though considerable life re- mained the mantle whole. For some time was thought that there was some sort harmonic motion the machine which caused the mantle fail regu- larly distributed points. will noticed that there are six points failure the mantle shown Fig. The six failures and their location soon led the correlation these weak areas with the six risers used when the mantle was cast. Subsequent in- vestigation the foundry showed that there were excessive shrinkage areas under each the six heads, and, furthermore, this shrinkage was concentrated the outer fibers the mantle. Since maximum stress during operation the crusher the outer metal fibers, rapid localized failure was the in- evitable result. The foundry was faced with the necessity immediately changing casting practice that shrinkage areas would eliminated con- fined unimportant Long-range experimentation with pattern-size pilot castings was out the question because the labor and metal expense involved and the exorbitant cost completely ra- diographing the large areas. was then decided use to- scale models. Many miniature cast- ings could made and these could incorporate every conceivable cast- ing practice. They all could poured from the same heat points failure. This 7-ft. mantle used for crushing ore has worn down in. in. thick. The six points which failed first correspond the location the six risers used during the casting the mantle. THE IRON AGE, June 18, 1936—27 ‘Se } = i > ) ) 4 a ; WR 1G. 2—This miniature casting measures in. across and was cast under identically the same conditions the full-size mantle Fig. The radiograph was taken the point designated the arrow. Note the large shrinkage cavity, which siderably darker than the step the penetrameter faintly visible the radiograph. metal, thereby minimizing experi- mental errors, and, also, each cast- ing could diagnosed radiograph- ically one film. First, Amsco made to-scale model the liner which had failed. This shown Fig. Over-all dimensions the pilot casting only in. across the widest section and having gross weight about 100 important point out, however, that pouring the to-scale model, was found that the walls were thin that the metal froze quickly that concentrated shrink- age occurred. then became neces- sary increase the wall thickness the model casting duplicate the solidification lines the full- size mantle. Therefore, the model shown the full-size mantle casting, having over-all dimensions but ratio wall thickness. All other casting practices were identical, that is, the model was poured flat using one gate and annular feeder and six risers distributed IRON AGE, June 18, 1936 about such castings were made and examined. One had two inter- connected gates and two risers, an- other was poured inverted po- sition and had six risers, another had two risers connected with the gate and two risers the opposite side, and still another used par- tial ring with the gate one riser. Chills were used num- ber cases, some were cast flat, others were cast 25-deg. angle, and few were deg. off the horizontal during pouring but were shifted deg. the opposite di- rection when the mold had filled. these many varieties only few will detailed and compared. the table (see page 98), full cast- ing data and radiographic results are given for six different to-scale models, and Figs. show actual photos two these models segment each case. The casting Fig. (No. the table) was the original practice—note that there area considerable shrinkage under the one head, and 3—Another miniature casting, using one riser opposite the gate. This not the optimum casting practice; for the radiograph shows considerable porosity and blowholes under the head. equally around periphery. After the risers and gate had been removed, the model graphed and showed six shrink- age areas comparable position with those the full-size casting. The next step was pour great number model castings covering numerous variations foundry technique. All together, there are similar areas under each the other heads. The casting Fig. (No. the table) was the final practice adopted. There was shrinkage, the yield metal was increased over 100 per cent and foundry practice was greatly simplified. Only one head was used and the mold was poured 10- deg. tilt and then shifted deg. a ; 4 4 . = ~ Ow the opposite direction. The angular feeder and five additional heads used the original practice were completely eliminated. Furthermore, when the technique used Casting No. (Fig. was incorporated full-size model, none these advantages were lost. The full-size mantle was poured with only one gate, and the 10-deg. shift each side the horizontal during and after pour- ing was accomplished means vice these mantles showed ten- dency fail rapidly particular sections. The complete mantle wore down uniformly, and users were pleased with the much longer life each installation. Consideration all these casting practices, and, specifically, the excellent results obtained with Casting No. illustrate the im- portance directional solidifica- tion. The series experiments proceeds from the original casting practice (Casting No. having collection ineffective 4—A miniature casting using two risers and two gates. The spreading cavity shown the radiograph proof that this practice undesirable. The arrow indicates the location the radiograph. heads and yield 38.5 per cent, through approximation the preferential lines imposed chill- ing (yield 59.7 per cent—Cast- ing No. the table), the ideal tained feeding from the last and hotter metal poured (yield 77.7 per cent—Casting No. the table). stated before, the trans- fer this latter practice full- scale production was accompanied eminently satisfactory improve- ment internal qualities and foundry yields. Advantage X-rays The results obtained are prac- tical demonstration how minia- ture casting can used develop superior casting and, incidentally, simplify foundry practice and improve the metal amazing degree. The scope this investigation would 5—The radiograph shows that this miniature casting sound. One head connected with the gate used, and, tilting, the metal solidification approaches the ideal free shrinkage which obtained feeding from the last and hotter metal poured. results were obtained when the practices developed this model were transferred full-size casting. have been utterly impractical full-size pilot castings had been used, inasmuch the metal, labor and radiographic costs would have been prohibitive. Even the smallest jobbing foundry could find ad- vantageous experiment the same manner when order call- ing for number duplicate cast- ings received. Instead radio- graphic inspection the to-scale models, would feasible break them down for visual inspec- tion. But there doubt that control would the more advantageous. Undoubtedly, satisfactory X-ray installation beyond the financial reach smaller founders, but even many the larger melt- ers have still resisted the self-evi- dent competitive advantage be- ing able cooperate with buyers turning out superior work means radiographic control. such equipment cannot squeezed into the budget, would probably profitable for most foundries, both large and small, occasion- ally rent capsule radium for the inspection specific job. Gamma-ray technique much sim- pler than X-ray; can learned (CONTINUED PAGE 98) THE IRON AGE, June 1936—29 ig 7 e 5 ~ “9 j 2 | ‘a | OVING stairway aluminum the Chicago store Sears, Roebuck Co. have been finished the Alumilite process. Aluminum Co. America photo. ALUMINUM one the “big four” among metals and, from the point view color, ranks next copper. Aluminum takes plate and can plated onto other metals that much that has been said about plating for color and about the coloring electrodeposited coatings previous articles this series ap- plies also aluminum. Heat-treating has little with the coloring any the non-ferrous metals. Also, alloying, which seemed important for copper and brass, has relatively little color importance for most the white metals except they are alloyed with copper, which case the coloring processes are those which were described previous 30—THE IRON AGE, June 1936 article this series. Plating and chemical treatment therefore con- stitute the chief methods color- ing the white metals. Aluminum, while lacking color and appearance value cast rolled, one the best metals for coloring and for giving different surface tex- tures. Coloring Aluminum dead white coating may produced aluminum boiling the parts lime mixed with lit- tle calcium sulphate. The solution held 185 deg. and made with grams calcium oxide and liter solution. the use this method, care must taken re- move the solution daily and agitate the bath prevent settling. The method flexible thickness coating depends time immersion. The times re- quired produce different thick- nesses coating are follow: 0.0010 in. min.; 0.0017 in. (3) White Metals ° ° ° HERBERT SIMONDS and YOUNG min.; 0.0018 in. min.; 0.0020 in. min.; and 0.0024 in. 240 min. Coatings produced this man- ner have the following chemical analysis: Aluminum oxide, 53.7 per cent; calcium sulphate, 14.0 per cent; aluminum sulphate, 03.3 per cent; and water, 29.0 per cent. While the above method gives dead white pure aluminum, shades off gray many the aluminum alloys. The coating, how- ever, pure aluminum fine grained and remarkably adherent. fact, strip aluminum may coated this manner and then bent without causing any cracking separation the surface. The abrasion resistance, however, low. yellow gold color with gray- ish tinge produced aluminum immersing the parts solu- tion containing per cent potas- sium permanganate and 0.5 per cent copper sulphate. This solution oloring a. should kept from 180 190 deg. and about min. re- quired for the process. yellow red surface produced immersing aluminum parts solution 2.5 per cent potassium sulphide, 0.1 per cent alizarine, and 0.1 per cent morine. This also should held from 180 190 deg. F., and the immersion time min. yellow gold with light silver tint produced with solu- tion 2.5 per cent potassium sul- phide, 0.1 per cent morine, and trace alizarine. this case the result secured more quickly and some manufacturers have found min. immersion sufficient. The tem- perature, with the previous solu- tions, held from 180 190 deg. Seldom iron color desired aluminum, but sometimes such special effect match surround- ings. uniform although dull iron color may easily secured im- mersing aluminum solution 2.5 per cent potassium sulphide and 0.1 per cent vanadium sulphide. solution 2.5 per cent potassium sulphide with 0.1 per cent morine will give aluminum interesting bronze color. The solution usual- held from 180 190 deg. and takes hr. immersion get the full effect. Permanence Finish Some the interesting surface effects aluminum are subject tarnishing and thus the various processes must selected with the exposure conditions mind. Some excellent clear lacquers have been developed for protecting colored aluminum surfaces. When condi- tions call for outside exposure the uncoated metal most the bright colors are unsuitable. stable velvety gray color may obtained immersing alumi- num and aluminum alloy parts boiling solution containing 100 grams di-ammonium phosphate and grams manganese nitrate Sand blasting frequently em- ployed for producing stable surface appearance and many times found more satisfactory than pick- ling. Some interesting methods pro- ducing deep shades aluminum have been developed recently, and undoubtedly the possibilities this direction are very great. solu- coloring iron and steel and their alloys and coloring copper and its alloys were described the first two articles this series, which appeared March and April respectively. This article considers most the industrially important except zinc. Specifically, describes the coloring aluminum, cad- mium, chromium, lead, plati- num, rhenium, rhodium and The next article this series will describe the color- ing zinc and the fifth article will discuss metal col- oring costs and other com- mercial considerations. Mr. Simonds vice-presi- dent Metal Products Ex- hibits, Inc., Rockefeller Cen- ter, New York. Dr. Young, associated with Dr. Colin Fink Columbia University engineering, the technical director the United States Research Corp., Long Island City, monium molybdenate and grams sodium acetate, with small amount ammonium chlo- ride per gal. water, will give deep black color aluminum parts about min. immersion time. Care must taken after coloring which will used HIS worker coloring alum- inum alloy tubes for fishing rods. a thoroughly wash, order re- move any traces chloride. Another method securing black aluminum dip the parts solution containing from 1.35 specific gravity, and liter solution. slight modifica- tion this solution will give brown color. One method in- crease the copper nitrate about grams and heat the solution 180 deg. range browns then may secured varying the time immersion. deep brown Aluminum may etched with any one several acid solutions give interesting matte surface. Also, the anodizing process gives attractive color and texture and furnishes excellent base for pro- ducing wide range colors the alumilite method. Anodizing Aluminum Aluminum coloring the process creating colored compounds the surface impossible because the compounds aluminum are colorless. However, aluminum oxide finish may produced and this turn may colored almost any hue desired. The commercial methods for pro- ducing oxide finish aluminum fall into three groups: (1) Chromic acid group, (2) sulphuric acid group, (3) acid group. The chromic acid method gives films which are more less opaque and produce the pure metal pearly gray color. These films are resistant corrosion attack, but x 3 the operation requires equipment, control, and lengthy batch operation. The resistance abrasion increases with age. The acid method pro- colorless and transparent coatings, and the freshly formed condition these are rather harder than the chromic acid deposits. Also, the process relatively inexpensive operate, requires little special equipment, and the time operation short. The oxalic acid films are nearly transparent, with slightly yellow tinge, and the hardness may varied from extreme brittleness soft and flexible films. When all conditions are taken into account seen that the sec- ond method, which makes use sulphate film, far the most important commercially and this method which will consider- some detail here. Whenever aluminum made the anode electrolyte dilute acid containing amounts chemicals prevent amp. per sq. ft. passed through it, oxide film produced the metal. practical operation the acid concentration the bath may varied between per cent and possible, the proper selection conditions such tem- perature, current density, time treatment, voltage, metal alloy used, and acid concentration, produce coatings which will integral part the metal and which will not chip, and yet will hard chromium. The thickness the coatings varies from 0.0003 in. 0.001 in., depending upon the procedure. The light reflectivity the coating approximately per cent less than the pure aluminum. One the authors (Dr. Young) has produced coatings with attractive appear- ance cleaning the metal cer- tain types etching solutions which incidentally increase the re- flecting power. Coloring After the oxide coating has been created then possible color the film dipping the parts aqueous solutions organic dyes. essential that the dyeing done immediately after the coating has been produced and washed, for the coating allowed dry, the 32—THE IRON AGE, June 1936 pores absorb the surrounding air, thus preventing the dyes from penetrating the film. The dyes are believed form “lakes” with the coating. When these compounds are formed, being insoluble, they are precipitated the interstices the coating. The dyes used are generally acid nature and soluble water. The temperatures these solutions vary from 180 deg. The colored films thus produced are organic, and therefore are not stable. This has proven handicap, the finish generally loses its attraction from months. For this reason inor- ganic colored materials have been used with more promising results. Dr. Young also several inorganic colored coatings, using the anodized aluminum base. This consisted anodizing the metal coloral (an anodizing solution produced the Re- search Corp., Long Island City) and then submerging solution containing 100 grams fer- ric sulphate liter solution. After remaining the solution, which kept 212 deg. for warm water, and placed saturated solution containing cyanide liter solution for min. After removing, the coating rinsed warm water. this method the ferric ion, which dis- solved the pores the anodized coating, unites with cyanide ion, producing the known blue compound, potassium ferrocyanide. This compound pigment which produces very neat shade blue which unaf- fected sunlight. Some methods coloring alumi- num are the same those used for and they will described later article. However, one two the methods common sev- eral alloys will considered brief- here. Most any the alloys aluminum, cadmium, tin and zine may colored immersion first solution ammonium molyb- denate which kept alkaline addition ammonia. The solutions ammonium molybdenate liter solution. After brief immersion first solution, second solution used, made adding the first sodium thiosulphate. Immersion plated food con- tainers have been at- tractively colored harmonize with their surroundings. this second solution for some- what longer interval. For success with aluminum small amount chloride frequently added. The resultant color most the alloys slightly irridescent brown. Some them have gray tones. Zinc this process becomes black. Iron assumes fine dark brown color. Additional color effects may secured passing electric cur- rent through the second solution the time dipping. Aluminum oc- casionally colored alloying, : | - = a 4 | ; 4 previously described. excellent imitation gold alloy has per cent copper and per cent aluminum, with small additions, generally less than per cent, nickel, gold and iron. Alloys iron containing small amounts aluminum may col- ored blue treatment with sodium hyposulphite solution. This solution consists oz. sodium hyposulphite dissolved gal. water which added oz. lead acetate mixed gal. wa- LUMINUM and metals are colored for and decoration multitude prod- ucts, which this furnace one the most interesting. is cage ter. The solution heated 197 deg. F., and gives lead sulphite coating onto the immersed parts. Color varies with time immer- sion. excellent black finish aluminum produced with am- monium molybdenate oz., am- monium hydroxide (30 per cent) oz., and water gal. This solu- tion used with electric current from amp. per sq. ft. volts. The solution held be- tween and deg. and ratio kept between the anode and the cathode. Anodes are usually sheet steel. Coloring Cadmium Cadmium has attractive na- tural color somewhat like but under similar conditions cadmium will not tarnish readily, and, therefore, years past has had quite vogue electrodeposited coating for steel and other metals. This subject has been cover- other articles and the pre- sent price cadmium high, due its use constituent bear- ing alloys the automobile indus- try, its importance coloring not very great. The high price cadmium having the effect stimulating the use deposited zinc coatings and many new processes for producing fine grained bright zine coatings have been developed. These will de- scribed more fully the next article under the heading zinc. Cadmium and zine are closely related metals and one may usually substituted for the other either plating alloying. For in- stance, cadmium may tuted for nearly all the zine alloys, and bronzes made from cadmium are claimed have some distinguishing features. fact the bearings now popular auto- mobiles are essentially cadmium bronzes. One the usual baths employed for coloring cadmium consists potassium chlorate, grams; and liter solution. The cadmium parts should thoroughly cleaned, and care should taken add copper sulphate the process con- tinues, for copper precipitated out the solution continually. the other hand, care must taken not have the copper sulphate content excessive. Usually added quantities not more than grams liter. The re- sults vary, due time immer- sion and concentration, and the color may graded from deep black old silver. good black cadmium produced with grems potassium chlorate, liter solution. This varies from the previous method that chlo- ride has been substituted for sul- phate. Several good browns may pro- duced cadmium, but because the diminishing use this metal the finishing field, these will touched but briefly. concentrated hot solution sodium thioantimonate will produce excellent brown tints cadmium. Some experimenting with this solu- tion will develop variety in- teresting colors. Another solution for brown cadmium consists grams copper nitrate and grams potassium permanganate liter solution. This used about 180 deg. Chromium and Rhodium The information methods coloring chromium meager, and further research work very de- finitely needed this field. satisfactory black color produced chemically, described the first article this series connection with chromium plating steel. Chromium and chromium alloys, course, are becoming increasing- important for their color ap- pearance value. general, chro- mium difficult metal coat color. has the peculiar property resisting wetness, that is, water doesn’t seem wet the metal sur- face least slow wet it. However, with care possible successfully plate all the reg- ular platable metals onto chromi- um. Several manufacturers are now turning out satisfactory chro- mium steel watch cases which are gold plated. This somewhat tricky job and for success upon first destroying the passive (CONTINUED PAGE 99) THE IRON AGE, June 18, 1936—33 mi- for ev- ef- ine rst ter he or. Pennsylvania Railroad Generally: Résumé Recent the Manufacture Rails, Which Ended Transverse Trouble. More Specifically: Bethlehem Steel Rail Heat-Treating Pro- cedure and Method Reducing End Batter. FIFTY years ago rail- roads experienced very little trouble with rails. They were interested principally wear. There was cause for apprehension account breakage, since the weight the rail was far excess that necessary for the light-wheel loads and low speeds. This condition has been respon- sible for the statement that fre- quently heard today that “old time rails were better than those now produced.” This unjus- tifiable conclusion based upon lack appreciation the much great- severity the conditions that modern rails must meet. Rails have increased weight. mon use, compared with rail which was the maxi- mum years ago. This per cent increase weight, however, much more than offset 100 per cent increase static wheel 34—THE IRON AGE, June 18, 1936 loads combined with higher speeds, which raise the dynamic loads measured values twice that the static loads. Consequently there now far greater pressure the wheel the rail and this confined area contact only slightly larger than under the old conditions. The result has been increase not only wear but the number rail failures. The first type failure occurring large numbers was the split head. This was main- confined rails rolled from the top ingot. These failures were troublesome, but they gener- ally developed gradually and plain sight inspectors and were generally removed before they be- heads increased under the growing severity traffic, railroads ob- jected strenuously. However, the railroads were more annoyed than they were alarmed. They were alarmed, however, wreck which occurred 1911 Manchester the Lehigh Valley Railroad and which was traced broken rail. examination this rail showed that the breakage had taken place result internal transverse rupture during service which had gradually devel- oped within the rail head without any external indications failure. This marked new phenomenon rail failures which now common- known the transverse fissure. recent years transverse fissures, more through their insidiousness than through their frequency, have been the cause more concern the rail maker and rail user than all other types rail failures. Much thought has been given transverse fissures. What causes the disease? What the cure? The last word has not yet been said the cause, but much has been done the way cure. Nearly years ago, Messrs. Sandberg London, England, in- ternationally known rail engineers, pointed out the probable connection between shatter cracks and trans- verse fissures. According the Sandbergs which occur occasionally rails “as rolled” may act the foci from which transverse fissures gradually develop within the heads rails during service. According the Sandbergs, “one the chief causes” shatter cracks are stresses caused substantial difference temperature during cooling between the outside metal and the interior metal, more par- ticularly the big mass the head the rail.” Shatter Cracks Prevented They believed that the occur- rence shatter cracks could prevented the transverse fissure problem would solved. Accord- ingly, they instituted exhaus- tive series experiments this direction. Before the end 1928 they had developed method controlled-cooling the Cargo Fleet Iron Steel Works Mid- dlesbrough, England, which effec- $ ERRAILS for the HORSE lley age ‘ing vel- ure. res, ave han een srs. in- ion ns- the res ads ing are ing tal ar- the tively prevented the occurrence shatter cracks. the succeeding year they introduced this method into the United States, where, after period several years’ experi- mentation the higher carbon American rail the Bethlehem Steel Co., the process was adopted More recently the method has been adopted Inland Steel Co. and the Colorado Fuel Iron Co. Other investigators, Gerhardt the Bethlehem Steel Co. and Mackie the Dominion Steel Coal Corp., Ltd., Sydney, Nova likewise diagnosed shatter the principal cause for transverse fissures and, like the Sandbergs, found the cure shat- ter cracks the controlled cooling rails. the present time the last-mentioned company subject- ing its entire output rails controlled-cooling. The ideas and practices the Sandbergs, Gerhardt and Mackie have been confirmed essentials recent scientific investigation. The work, for example, conducted the University Illinois, under the auspices the Association American Railroads and the Rail Manufacturers’ Technical Commit- tee, especially significant. LOSE-UP view mitred rail. Photo Bethlehem. BELOW mitred rail joint. Photo Bethlehem. ge this work the University Illinois, equipment was used subject rails, under laboratory con- trol, conditions simulating those actual service and thus de- velop transverse fissures those rails having susceptibility thereto. “Tests rails under rolling loads” this equipment “have yielded fairly convincing evidence that fis- sures rails usually originated shatter cracks which formed the rails during the process manu- facture. All laboratory-developed fissures were rails and about per cent the service-fissured rails sent the investigation showed evidence shatter cracks outside the main fissure.” (American Railway En- gineering Association Bulletin No. 376, June 1935.) From the above-mentioned bulle- tin also appears that the Uni- versity Illinois made compara- tive tests hot-bed cooled and controlled-cooled rails from four different mills and that while some the hot-bed cooled rails had shatter cracks and developed in- ternal fissures when subjected THE IRON AGE, June 18, 1936—35 4 > rolling load tests none the con- trolled-cooled rails shatter cracks manifested internal fis- sures when subjected such tests. Not all the rails cooled the usual way the hot-bed contain shatter cracks. known that only very small percentage the rails rolled contain shatter cracks, and even those rails the number shatter cracks small. But their occurrence insidious. Shatter cracks are sometimes found rails produced from particular ingot heat and absent from other ingots the same heat. limited portion rail some- times found contain few shat- ter cracks while the rest the rail entirely free from them. Obvi- ously there can real assur- ance freedom shatter cracks unless all rails are sub- jected the controlled cooling op- eration. Without vaccination the majority human beings might not have smallpox, yet universal vaccination the sound prophylaxis. Over five years experimenta- tion was necessary determine just the conditions requisite for controlled cooling American rails, and develop the process commercially effective scale. applied the mills the Bethle- hem Steel Co., for example, the practice its broader aspects may outlined follows: Bethlehem's Process The rails are eooled the hot- bed the usual manner until the temperature has dropped low 1000 deg. but not less than 932 deg. They are then placed boxes tanks for slow cooling, placed each box insure slow and gradual drop temperature. After being loaded, the boxes are carefully covered, and the joints are made sufficiently tight avoid cool currents air coming into contact with the rails. Moreover, the boxes are protected from ex- posure snow and rain. The rails remain the boxes tanks until their temperature has dropped be- low 400 deg. Practical experience, well extensive laboratory experimenta- tion, has indicated the importance starting the controlled cooling sufficiently elevated temperature, but, course, below the transfor- mation range and continue the retarded cooling temperature below 400 deg. There has been 36—THE IRON AGE, June 18, 1936 are permitted cool the hot-bed about 1000 deg. F., shown the photo and, finally, covers are sealed the boxes and the rails cool about some difference opinion among investigators within what ranges temperature, during cooling, rail steel most suscepti- ble the formation shatter cracks. The Sandbergs, for ex- ample, inclined the belief that the tendency shatter cracks was greater between 932 deg. and 650 deg. F., while Gerhardt and Mackie had the view that the ten- dency shatter cracks was great- est below 650 deg. Both the Sandbergs and Gerhardt agreed, however, that practice was important start sufficiently HOTOMICROGRAPHS the structure treated and diameters, heat-treated rail 100 diameters, untreated elevated temperature allow substantial margin safety. Mackie, describing appli- cation his process which was “100 per cent effective eliminat- ing all traces shatter cracks,” stated that the rails were allowed until visible redness dim light had disappeared, and then were placed the cooling tank promptly practicable. Apart from the prevention shatter cracks, the controlled cool- ing substantially reduces sidual stresses the rails, thereby ot photo about untreated reated Beth lehem. greatly minimizing the tendency the development weaknesses the rail, other than transverse fis- sures, during service. The con- trolled-cooled rails show substan- tially higher results bend tests than ordinary hot-bed cooled rails. The ductility better. All these results are obtained without appre- ciably affecting the hardness the rail determined laboratory tests well measurements the wear the rails track. The production controlled- cooled rails Europe has reached the figure approximately 1,000,- rails: From left right, the left; two yoke transfer the rails cooling box, shown the middle, 400 deg. F., shown the right. Photos supplied Bethlehem Steel Co. 000 tons and the production such rails the United States and Canada now aggregates about tons. Rail Heat Treatment the efforts meet the in- creasing need for rails higher physical characteristics, substan- tial advances have been made through heat treatment. The term treatment” here used be- cause its general acceptance the industry, instead the more accurate, but also somewhat more cumbersome, expression, “quench- ing and tempering.” untreated rail 2500 diameters, and heat-treated rail 3000 diameters. Photos When the demand for rails capa- ble greater and greater loads first appeared, metallurgists natu- rally began consider the feasi- bility applying rails the well- known effects quenching steel greatly increasing the hardness and strength. Some years ago various methods heat treating rails began appear the tech- nical journals and patents. was soon discovered, however, that the problem was not simple. The usual methods heat treating steel articles could not success- fully applied rails. rail offers certain special ob- stacles ordinary quenching oper- ations. Its peculiar cross-section with its unequal distribution metal, its great length, the great mass metal, particularly the head, and the high carbon content, all contribute the difficulty effective, yet safe, quenching. For years attempts were made solve the problem with but indiffer- ent success. All the ordinary methods developed ciently great cause ruptures the metal, particularly within the interior the head. After period experimenta- tion lasting some years, Edward Kenney, the Bethlehem Steel Co., discovered process pre- venting these ruptures, which described United States Reissue Patent No. 17,240. The practical embodiment the Kenney process has been practiced the Bethlehem Steel Co. involves the rail while cooling from mill heat, discontinuing the quench definite temperature promptly effecting equalization elevated temperature and finally subjecting the rail controlled cooling. This treatment exceedingly important. The present trend decidedly the direction higher speeds train service. Under the higher speeds tracks today, the dynamic wheel load sometimes ex- ceeds 100,000 lb. times nearly all the enormous axle load pair wheels concentrated single wheel. The entire braking effect high speed may ap- plied small area contact between one wheel and the rail amounting only from 1/3 1/2 square inch. Under these con- centrated loads the surface metal the rail tends flow. This ten- dency flow opposed the underlying metal, thereby resulting THE IRON AGE, June 18, 1936—37 % a vas ro ere as great tensile stresses the in- terior metal. With the high speeds today the need for high physical characteristics rails great; with the prospective, and probable, higher speeds the near future, the need will imperative. Heat treatment rails effectively meets this need. study the accompanying chart and photomicrographs, giv- ing the comparative physical prop- erties and structure treated and untreated rails, will plainly indi- cate why the treated rails are far superior resisting the stresses induced high train speeds. Ken- ney’s aim was produce rails which the elastic limit suffi- ciently high greatly minimize entirely prevent the plastic flow the outer metal the rail head due the concentrated wheel loads. The chart marked increase elastic limit due heat treatment. Not only does the greater elastic limit inhibit the tendency plastic flow the outer metal the rail head, but the high elastic limit the inner metal enables the steel resist effectively the tendency flow the outer metal. Moreover, the heat-treated rail has far greater life than that the untreated rail, due its in- creased resistance wear. Ac- cording recent reports from five railroads the average wear the high rail, when heat treated, was only 54.6 per cent that the un- treated rail, and the low rail, when heat treated, but per cent the untreated rail. Messrs. Sandberg England have developed special method heat treating rails involving the application vaporized water the rail head, followed controlled cooling. This process now used most the rail-making plants Eu- rope, where March this year more than 100,000 tons rails were produced through the use this process. While this process has not had general appli- cation this country, its possi- bilities must not overlooked. Correcting End Batter One the weakest elements railway track under modern service conditions the joint. Long be- fore rails are worn out the abrasive action the wheels, the joints have usually become loosened wear the contact surface be- tween the rails and joint bars, par- 38—THE IRON AGE, June 18, 1936 ticularly under the heads the rails and the tops the bars. When the wear has become too great, rails are taken out track, the ends cut off remove badly worn parts, new holes drilled, and new joint bars installed the shorter length rails. tively short life the rail ends and joint bars due most part the impact the wheels pass- ing over the joints, especially where the impact has battered the rail ends form depression. Efforts have been made cor- rect this battered condition de- positing molten steel fill these depressions, followed grinding danger this practice because cracks the rails thus treated are very likely result. far cheaper and safer prevent minimize this battering than at- tempt correct after has occurred. The method most com- monly used for accomplishing this that hardening the ends the rails. Several methods harden- ing rail ends are being used the present time. End Hardening Cold Rails one method, the top surface the head the region and adjoining the end cold rail brought very high tempera- ture application the electric are torch and then subjected water, oil, air. The conduction heat the interior the rail head, during the heating operation, slow, and many instances the depth the metal heated quenching temperature may not more than in. When the quench- ing medium applied the thin layer heated metal almost in- stantly quenched the combined chilling action the quenching medium and the cold portions the rail. There gradation hardness. Moreover, cracks fre- quently form the junction the hardened and unhardened metal. Rails which are laid track be- fore end hardening must, neces- sity, hardened while the body the rail cold. While considerable tonnages rails have been end hardened this way, there have been frequent breakages and spall- ing considerable areas the hardened metal. Hardening Rail Ends from Mill Heat The most satisfactory method for end hardening rails, not mere- from the standpoint safety, but also from technical and eco- nomical considerations, quench the end regions while the rails still retain the mill heat. the mills the Bethlehem Steel Co. the end regions are treated the rails lie cooling the hot-beds. plicity water jets applied RINELL hardness curve for