The Iron Age 1942-10-29: Vol 150 Iss 18

This 14,000 Ton Pure Hydraulic Forging Press, recently completed for the War Program, the Second huge press this size designed, built and installed MESTA the same plant. att pe 4 a * 4 % ‘ j ‘ Battles wax and wane—but war the production front must forward with unabated energy. Man power ous other ob- solete methods. Today’s urgent need for cranes being met with Whiting Victory Cranes—streamlined, mod- ernized equipment keeping with wartime needs. Although there are frills extras, their performance fully guaranteed. You are assured the same durable construction and smooth operation always. Write for information. Whiting Corpora- tion, 15601 Lathrop Ave., Harvey, TRAVELING CRANES ¢ (LHL. New Handbook for crane tors contains structions for guidance oper ators, repairmen, others. will furnished gladly request 4 OCTOBER 29, 1942 VOL. 150, NO. VAN DEVENTER President and Editor BAUR Vice-President and General Manager ° ° ° Managing Editor, LIPPERT News Markets Editor, ROWAN Technical Editor OLIVER Associate Editors Art Editor, WINTERS Editorial Assistants Resident District Editors Washington Pittsburgh Washington Chicago Cleveland Detroit OSGOOD MURDOCK Francisco Editorial Correspondents DEARING ROBERT McINTOSH Buffalo Cincinnati FRAZAR RAYMOND KAY Boston Los Angeles HUGH SHARP JOHN McCUNE Milwaukee Birmingham SANDERSON ROY EDMONDS Toronto, Ontario St. Louis BACON Seattle ° ° DIX, Manager Reader Service ° ° ° Advertising Staff Union Bldg., Cleveland Herman, Bldg., Philadelphia . Hottenstein, 1012 Otis Bldg., Chicago Kay, 2420 Cheremoya Ave.. Los 100 East 42nd New York 7310 Woodward Ave., Detroit 100 East 42nd St., New York Box 81, Hartford, Conn. on, Market Research Production Manager. and Layout. ° ° ° Bureau Circulations ber, Business Papers n the Industrial Arts Index. Subscription Possessions, $8: Forei gn, $15 year. Single copy, cents. ° ° ° Owned and Published CHILTON COMPANY (Incorporated) Executive Editorial and Offices Advertising Offices stnut and Sts. East 42nd St. iladelphia, 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 C. S. BAUR. Vice-President WILLIAM BARBER, Treasurer JOHN BLAIR MOFFETT, Secretary JULIAN CHASE, THOMAS KANE HARRY DUFFY CHARLES HEALE Editorial The Empty Chair Technical Articles What Current Briquetting Practice? Planned Time Study Standards Investigation Welding Problems. New Equipment Speeds Aluminum Heat Treating Worm Reamers Reforged Size Flame-Priming Method Utility Enamel Finishes for Light Alloy New Heat Treating Equipment. Features Assembly Line Washington West Coast Fatigue Cracks Dear Editor News and Markets This Industrial Week News Industry Coming Events Personals and Obituaries Non-Ferrous Metals Machine Tool Activity Scrap Markets Iron and Steel Scrap Comparison Prices Finished Steel Prices Warehouse Prices Index Advertisers Copyright, 1942, by Chilton Company (Ine ) This Week in... q Peirce Rob 102 108 Che and nished quest. HOW MUCH MATERIAL CAN Save Manpower, too The National Safety Council authority for the statement that 460 million man-days were lost through accidents this country last year. That’s enough time supply army 200,000 with full fighting equipment. Remind your employees play safe the time—on the job away from it. Casualties the home front are every bit damaging the fighting fronts. 28—THE IRON AGE, October 29, 1942 problem simple state. The nation’s supply essential materials must made farther —particularly the vital alloy steels. More must done with less. Nosing out the scrap—the idle dormant metal—is highly necessary, but it’s only half the answer. The other half lies using alloy steels machine set-ups and plant proce- dures reduce rejects, spoilage and undue scrap—using lower alloys wherever possible—plugging every loophole waste. Scrap the old steel, conserve the new; that’s the only way the nation can secure greater yield war equipment for every ton alloy materials taken off the national stockpiles. can help you save, through any printed personal assistance, call us. | “4 STEEL CORPORATION GENERAL OFFICES: PITTSBURGH, PENNSYLVANIA A-8678 > , > Photo courtesy Popular Photography aa 4 sx, 7 THE The Empty Chair AGE OCTOBER 29, 1942 ESTABLISHED 1855 HERE are some four million empty chairs the tables American homes today; chairs which not long ago were occupied our be- loved sons and brothers. And already, though the second front still come and have hardly begun fight offensively, many these chairs will never again occupied. There real democracy these empty chairs. They are found the homes the rich and the poor; the employer and the laborer. But sheer arithmetical weight numbers, there will far more these permanently empty chairs the homes labor than all other categories. For today have over million workers our labor forces. And that means per cent all the men and women between the ages and 59. Each one us, matter what his station life may be, re- sponsible for doing everything his power help win this war. responsibility not merely equal that the soldiers and sailors who are going abroad fight for their country but one that even greater. greater because they are risking their lives and many instances will lose them. greater because they are subject established dis- cipline while must depend self-discipline. Self-discipline not easy thing exercise democracy that has been based upon individual freedom. Yet must attain here home our daily work hope match the totalitarian efficiency the Axis powers. have not yet achieved that self-discipline here. had, would not hear per cent absenteeism some our war produc- tion plants. Can you imagine such things this happening the war produc- tion plants the Axis powers? Can you imagine German Japanese mechanic machine operator taking day off from work each week because happens feel bit under the weather because big wages are burning holes his pockets? This not problem that management can solve. personal problem for labor. perhaps, some instances, for labor unions. The American public, which labor such large part, will cheer- fully without meat coffee gasoline. will buy bonds the limit and undertake tremendous tax burden. will even resign itself the drafting our 18-year olds, most whom seem like babies their fathers and mothers. But the American people have the right expect that every man will his duty. And home that duty put every possible work- ing moment. not too much ask view our established working week. Remember, friends, empty place the bench machine may mean empty chair after this war home, perhaps yours. i if | | | | | | | | | | | | ° ° | | | | | 7 q 1g 4 4 4 > * * fz = a* limestone are blasted free, ready for the crusher. Blasting for Steel Pure Inland Limestone Helps Produce Steel for War Twice each month tons dynamite blast loose war jobs, for the Inland quarry furnishes pure 150,000 tons limestone the Inland quarry. This limestone essential the making fine steel. the equivalent block stone mile long, This limestone quarry only one many Inland- feet wide, and feet deep. Immediately follow- controlled sources raw materials. Inland also ing each blast, giant power shovels move operates its own ore mines the northern ranges, pick the limestone and load for transport and coal mines Kentucky. the modern freighters Complete control raw materials one the then carry the mills Indiana Harbor. most important factors making steel highest Quarrying limestone seems far remote from quality, maximum output, help win this war steelmaking. Actually one Inland’s vital production. SHEETS STRIP TIN PLATE BARS PLATES FLOOR PLATE STRUCTURALS PILING RAILS TRACK ACCESSORIES REINFORCING BARS * ‘ og = ¥ ¥ 4 ‘ 4 Pipa 4 * ~ ° ° ° PHAIR Western Editor, THE IRON Current Practice? IGE e Unloading cast iron briquettes Presented herewith survey briquetting prac- tice plants, giving details melting losses, die size, briquette weight, and the amount briquettes which can used charge. This information was collected find answers the questions put THE IRON AGE prospective users briquetting equipment. war one mighty battle lathes, milling machines and drill presses. This best exemplified the steel and cast iron turnings and borings that are pouring, ever increasing volume, into scrap dealers’ yards. The economic use these ma- terials, aside from the small quan- tity consumed chemical plants, has always presented problem. scrap metal, the importance ob- taining the full re-use value bor- ings and turnings most essential. Difficulty handling these ma- terials because their bulk and looseness, together with their er- ratic behavior open hearth and cupola, have been the chief stumb- ling blocks overcome de- veloping their wider acceptance scrap metal. Various means packaging simplify handling and melting have been devised. Practically all these methods have been discarded except that briquetting. This latter treatment has been acknowledged the most economical means handling the material, many cases paying for itself making available source scrap not otherwise available. one time the war agencies seriously establishment regional briquet- ting plants cope with the flow turnings and borings expected. the meantime, numerous individual plants have installed units since the emergency was declared 1940, in- orders tor such equip- tremendous. numerous inquimes concerning bri- practice which cannot answered the basis existing literature. attempt fill these voids, was decided enlist with considerable operating briquetting machines certain information. The results this survey, which participated, presented this the first survey its nature ever conducted, the data col- lected are not all comparable basis would desired. Too, indicated that many bri- quetting plants there lack detailed operating data equipment. THE IRON AGE thanks the plants supplying information that the data will value plants contemplating tion briquetting equipment. the plants participating the survey, six briquetted both cast iron and steel, while six handled cast iron only. The die sizes, bri- THE IRON AGE, October 29, the Pontiac Detroit foundry. — ~ * | ° i quette size, weight and production are given Table Briquetting machines are manufactured va- rious capacities. The output data given Table not necessarily represent the maximum capacity each unit. Various situations, such the amount material available, may exist individual plants that not permit utilizing the full capa- city press. the other hand, duce excess its rated capacity. The figures given Table indi- cate only what given plant ac- tually doing. These figures should not construed indicating ca- pacity ratings themselves. Note: The identification, plant etc., used only simplify tabulation and this marking not comparable all tables. Thus plant Table not necessarily Plant other tables. The plants participating this survey were asked they had ex- perimented with other and why had they standard- ized the size being used. ap- pears majority cases that the recommendations the ma- chine maker have given the most stance was reported that experi- menting resulted some costly lessons ram freezing, chipping the die, etc. several cases the same die used both cast iron and steel, although the briquette size not always the same due the different compressing charac- teristics the two metals. One plant reported starting with briquette, but going later in. increase production. This plant using small machine, but with 3-in. die able handle tons steel tons iron per 8-hr. run. There was general agreement that the melting loss encountered with briquettes around per cent, the exact average being 5.3 per cent. The melting losses are given Table II. Here again lack standardization report- ing makes difficult compare these losses. The circumstances sur- rounding the one loss per cent are somewhat unusual and are not those met ordinary practice. Too, experience also factor the melting losses. Plants that have been using briquettes for many years and who have made inten- sive study their action the cupola are usually able bring the loss below per cent, often the Another interesting phase the survey was the wide variance the amount briquettes used each charge. While the types casting being produced are the determining factor this ratio, was notice- able that several cases, plants making practically the same type iron differed widely the quantity briquettes used. quite pos- sible the factor supply, which was not accounted for the sur- vey, accounted for the difference. Table III shows the percentage briquettes used per charge. The question what maximum percentage briquettes which can used with charge again dependent largely upon the type casting poured. Heats con- sisting 100 per cent briquettes have been cast experimentally, but, according the survey, appears that most operators feel that per cent probably the economic maxi- TABLE Briquetting Practice Various Plants Output, Tons Per Plant Hr. Per Machine Size* Weight, Lb. Density, per cent First dimension diameter. Cast iron and steel. 32—THE IRON AGE, October 29, 1942 mum under today’s price conditions. connection with this problem interesting note that one machine tool casting maker com- mented that per cent cast iron briquettes could used make high grade machine tool cast- ings and that high per cent steel briquettes may used, but the carbon will low. Some the typical percentages used are follows: For both high test and soft iron, per cent steel and per cent ‘ast iron briquettes. plant run- ning cylinder iron reported having used high per cent cast iron briquettes. maker alloyed brake drum iron, which duplexed electric furnace, uses the fol- lowing charge: Cast iron briquettes per cent; pig iron per cent; returns per cent; alloys per cent. Another producer piston and cylinder iron regularly uses per cent cast iron and per cent steel briquettes. plant run- ning 40,000 tensile iron states that regularly uses per cent cast iron and per cent steel briquettes, although high per cent bri- quettes have been used. mixes, effect oil and other cupola problems contained article “Cupola Practice with pub- lished Aug. 27, 1942, 39. the question segregation borings and turnings analysis, appears that much work yet done, although several plants are already separating the nickel con- taining material from plain iron and steel. another instance, ma- terial separated into two silicon classes: 1.90 per cent and over and 1.90 per cent and under. course, some plants, running only one type iron steel, segregation not necessary. Another question the survey asked whether not was neces- sary make important changes melting charging practice cases was asserted that only minor changes necessary. Typical comments this question were: “Where high percentages steel briquettes are should made increase graphit- carbon.” “Use higher coke bed get better More desulphuriz- ing necessary. Used soda ash for this purpose.” ; q 4 q d n 4 a 0 0 4 a 2 b p a e a = a a a | ‘ | | | | | TABLE Melting Loss Using Briquettes Plant Per Cent Loss to6 3to5 H * L * Average §.3 Not reported. “Lower carbon pickup with cast iron borings, which must ad- justed for.” One plant warned that precaution must taken bring down high sulphur content. This was being accomplished, was stated, use ash, Purite, ton metal. This plant uses cast iron briquettes only, some which contain cutting compound. This compound largely removed draining. answer the question “did briquetting reduce your spout metal all plants the survey re- ported yes. While many were un- able supply estimates the extent the reduction, probably due the fact that this depen- dent upon the market price the borings, one plant estimated the savings per cent, another per cent, and third per cent. cos Probably the phase the survey was the wide range answers what were the advantages using briquettes compared with ordinary scrap. The following are typical com- ments: Lower cost scrap. When using home produced bor- ings, analysis melt can more closely controlled. Charging practice simplified due uniform size briquettes. Simplification storage problem. Assured scrap supply. Uniformity size. Assurance supplies under pres- ent Lower metal cost spout. Better micro-structure. More compact metal charges. Easier handle. general reticence was shown toward divulging cost figures, de- spite the assurance that all such data would held strictly confiden- tial and not used for any purpose other than this survey. Such cost data were reported were not basis permit direct compari- son. For example, one plant had constructed building and had in- stalled extensive conveyor ar- rangement handle the briquettes. The cost this building and con- veyor line, and its amortization was charged against the briquette costs, while another plant with the same situation, construction costs were disregarded. Another point divergence was the period amortization. The cost was also widely affected the degree which the capacity the machine was utilized, thus machine working hr. day has much lower cost per ton than ma- chine working only 8-hr. shift, the machine working only hr. may more than paying for itself. means establishing these costs common basis. One briquetting machine opera- tor, who noted for his work this line, warned that the layout design briquetting installation utmost importance deter- mining final cost. This because TABLE Per Cent Briquettes Used Each Charge Cast Plant Steel Castings Made 20-40 Machine tool varies Miscellaneous High test and soft iron Cylinder iron Alloy iron, duplex Piston and cyl- inder iron iron 30,000 Ib. tensile iron General gray iron Cast iron, pressure labor one the largest items the cost briquetting and the lay- out has important bearing this item. Another plant remarked that one time they had more chips than briquetting capacity, they added another hydraulic pump the ma- chine and increased its capacity per cent. turnings leaving the centrifuge which removes oil from the turnings the Pontiac foundry Detroit. After the turnings are fed into crusher and then the briquetting machine. THE IRON AGE, October 29, 1942—33 | l, | d ar | | ‘Ss, “ Cu thru Die Continuous la & Arrange Ww a j ~ - le ° i= c 7 fe 3 | - | x | 3 | je Ie = |e > 5 | a | bo « | in | 3 | | i | Hold in Pala Pos. Plac 2 Place Handful Pos. 4 = Clear Bridge Pos. e 7 2 < 3 Insp. for Slugs je e ~ > a Oil Puneh LH Pos = Wipe Strip b |= Drain Strip Ka Straighten End c Stock Rt. Side Up peed face the time card" identifies the part, material and equip- ment; itemizes the operating method; and carries table elements for compiling operation time, the task, the piece rate. EQUIPMENT TO BE PROVI DED Remove Parts = Tool Remove Slugs - Tool Cutting Pliers Cutting Shears Sqrew Driver Feed Board & Stand “O41 in Container Rag Brush Chute Chair | PRESS FEED BOARD \ > \* o GONDOLA POREUAN: CODE NO: 1G. 2—The reverse side the time card contains four elements show the equipment required, the part and layout the job. The section for notes the type and condition tools provided. ° ROPERLY time study records are impor- tant factor the establish- ment and maintenance uniform- ity manufacturing processes. This turn gives operating men true picture the advantages using standard labor costs de- rived from wage incentives. These records also supply quick source information assist the prep- aration accurate cost estimates. Yet too often the methods en- gineer cost estimator faced with the complex task basing his information selection studies which merely bear close 34—THE IRON AGE, October 29, 1942 ° resemblance the operations planned for the new part. They are often mere records stand- ards established for single job only. Detailed descriptions and timing material handling, meth- ods, and surrounding conditions are usually incomplete lacking. obvious that planned procedure taking studies can assist methods men and cost esti- mators compiling their figures more quickly and more accurately. The results will more consis- tent, labor standards can set faster, and the dollar made further. Intel- GEPPINGER General Wage Rate Department General Electric Co. ligent planning this sort will produce uniform breakdown similar identical jobs vide records all elements the cycle. addition, details the layout and method operation. The advantages gained this type planning are well illus- problem and its time study meth- ods. Fig. represents the face “standard time card” used this plant for computing labor standards for punch press opera- tions parts made from strip stock. The scope the card limited the following physical condi- tions: Equipment: Floor type punch presses. Materials: brass, copper, aluminum, fiber Textolite—not exceeding in. thickness, with width in. less and lengths ft. Operations: All opera- tions strip stock such blank, pierce and blank, cut-off, pierce- form and cut-off, and similar com- binations. Dies: Through, compound, cut- off, follow, Feed: Hand feed, either con- tinuous interrupted. Locating: means end stop, automatic stop, over guide locating pins, sight. Part disposal: Hand removal blow-off. Operations Record The “operation” “standard time” card takes the place the time study sheet record the operation and the method. The face this card (Fig. has three distinct features: Identification part, material and equipment; Interrupted } Loe. ever Pin - Sight ~ Drop in T.B. Pos. = - - | Pos. & Drop Pos. | be | Finger Stop } | Set by Sight | | - ° ° ° 1 | air Nozzle 4 2 12 15 16 OBSERVER; a ° q q ‘ itemized record operation od; and table elements for compiling the standard operation time, the task, the piece rate. The back the card (Fig. shows four elements: record the tools and equipment required; schematic floor layout; sketch the die; and column for com- ments and signature. The establishment standards means the card made three steps. The rate man will: (1) Observe the actual opera- tion, condition, and layout; re- cord all information necessary for the proper description the part, material, and equipment; check off the operating method and equipment provided; make comments conditions tools, equipment, and economy op- eration; and draw rough sketch. (2) Relate this information the table standard time values shown the “standard time re- port,” and calculate the piece price, recording the designated column each element that applies the particular job. (3) Present the standard time card the foreman, discuss the job, and obtain approval. Time standards tasks will then issued, and the card will filed the wage rate dept. The foreman will provided with copy this card assure uni- formity set for subsequent production runs. practical example deter- mining the piece price bump, form, and cut-off operation shown Fig. Physical condi- tions applying the job have been checked off the right, in- dicating that cut off die used, the part being ejected air and the press being run inter- mittently (interrupted). This col- umn also shows that the stock pushed against end stop; that the container holds approximately pieces; and that the end the strip becomes scrap which must put the scrap box. Other information needed for selecting the proper time elements study procedure New England plant fur- nishes quick, accurate ref- erence data for methods men and cost estimators. shown the head the card, such as: Speed press 130 r.p.m. Stock 0.062 5/16 in. ft. long No. strokes per strip No. parts per strip Length part for hand feeding in. Time Calculations With this information the basic time values for elements etc., can secured standard time report sheets which all values have been listed. Element A—Press Time: Data the standard time report sheets give the time per stroke for vari- ous types dies and arrange- ments. Reference one these sheets shows that time, based rate 130 strokes per min., with cut off die, blow off, and interrupted feed, 0.0157 min. This figure multiplied the number strokes per strip, 53, gives total time 0.8320 min. per strip. Element Hand Feed: The report sheets indicate feeding time for interrupted feed with end stop 0.0003 min., provided feed in. less. The actual feed this case in., hence this value posted the card and multiplied 53, the number pieces per strip. This shows that the 8-ft. strip can fed 0.0159 min. Element G—Move Tote Boxes: The notation the card shows 3000 pieces per tote box, hence the time per strip will be: 0.60 0.0106 min. per strip 3000 The figure 0.60 min. the stand- ard time for moving tote box. K—Place Stock Die: The time required pick strip and place die varies for different materials and sizes. The standard report gives time 0.0976 min. for steel strip 9-ft. long and 1-in. wide, this figure posted the card. Element L—Support Stock Feeding: For cut off jobs within the size limits the strip speci- fied the standard time figure given one the sheets 0.1003 min. Elements and Q—Place Stock and Remove Scrap End: Again, these particular operations can found tabular form the time report sheets and are merely post- the card complete the list elements necessary complete this group operations the part. the total 1.1124 min. general allowance per cent added, and calculations pro- duction and price are entered the proper spaces. This method determining operation times has been used this plant for some time and applied all new parts going in- production. When conditions arise that have not been covered previously and cannot changed fit into the established stand- ard pattern, they are analyzed and practical elements added. jobs special nature any job which the task, established this manner, questioned, watch stud- ies are taken check the fairness the standard. Setting Time Values The methods used for establish- ing the standard time tables and individual time values comprise: Time study actual observation, motion analysis from observation, and motion analysis from films. All studies made establish the tables standard times were planned thoroughly down uniformly. Variations like elements were carefully in- vestigated and compared estab- lish the causes and their possible relation the die, part, stock, surrounding conditions. cases that did not give conclu- THE IRON AGE, October 29, 1942—35 { | | i} | | ° ° ° ] d | e- Pp, ‘ee | study man uses time check off all physical conditions typical pierce and blank job. The piece price can then set without timing any part the cycle. sive answer, motion analysis was made from observations from films. This method was also em- ployed very short elements that could not recorded accurately the watch and required further analysis and breakdown into con- stants and variables. some the tables not all values could fore necessary plot the points available graph and deter- mine intermediate points inter- polation. After all basic values had been determined, the task remained arranging and combining related values for the purpose simplic- ity application. This has been done whenever practical without destroying the accuracy the final time value. Element Press Time, represents value this type and therefore cannot checked from the press speed. Assuming, for instance, press speed 130 strokes per min., the time per stroke would 1/130 0.0077 min. All table values for this particular speed, however, show higher values, since they are combined with values represent- ing other conditions that are relation press strokes. While the analysis was prog- ress, unsatisfactory conditions and undesirable variations methods were discussed with the 36—THE IRON AGE, October 29, 1942 floor supervisors order im- prove and establish them more uniform basis. Efforts were especially directed towards minor causes varia- tions from set up, die, and han- ° ° ° OLDING skeleton prepare for the scrap box. This Element the time card illustrated Fig. although the part not that detailed the card. dling conditions, which, reduced and limited, would permit estab- lishment practical time values. was suggested that the men re- sponsible for set-ups insure good operating conditions by: (1.) Making test run new set-ups, checking stocks and strip- per plate insure free feeding; checking burrs punched holes and accuracy centering the punch. (Studies available the same part indicated variations time feeding much 100 per cent because excessive (2.) Supporting the air nozzles for blow-offs rigidly and direct- ing the air jet accurately against the work piece. (3.) Placing chute aprons the rear the die prevent blow- off parts from being caught re- cesses bolts die clamps. (4.) Checking automatic (ram-operated) and finger stops, see that the stops work freely, yet accurately. (5.) Placing drop lights between the uprights every machine insure clear vision. (6.) Instructing the operator the proper use oils and com- pounds for use the stock well punch and die. (7.) Supplying the operator with effective hand tools for placing strip removing parts and for removal fasteners from raw ma- terials used for processing. (8.) Having raw materials, con- tainers, tools, oil, feed board and stand, etc., location before the operator the job. Advantages The advantages establishing tasks the standard time method may stated briefly: Tasks can set less than one- half the time formerly required the time study method. (2) Established tasks will show greater accuracy and consistency, the values are not affected the judgment the time study man rating per- formances. (3) Fairness tasks assured since all values are based normal pro- duction level performance which normal operating delays have been con- sidered and granted. (4) The record the method oper- ation shown the card will enable the set-up man reproduce like set-ups for future production runs, and, gen- eral, will keep supervision alert main- tain the established level standardiza- tion methods. (5) Use the standard time card re- sults more accurate estimating new devices relating the operation meth- ods the new parts data actually applied cards the files the wage rate department. Ww i pu the the tio ° ° WYMAN Research Laboratory, General Electric Co. welding two more pieces metal into single unit presents problems far greater than those concerned with the production sound weld. Ever-increasing mands welded structures require performance beyond that indicated apparent soundness. The rapid advances welding techniques which have taken place during recent years are consider- ably advance the application engineering, chemistry, and metallurgy the welding problems. While true that much effort has been expended welding processes from these vari- ous standpoints, there but small doubt that far greater amount nature must done order bring our knowledge welding processes state which standing methods. order accomplish these ends, becomes essential make comprehensive study and analysis each new welding problem from the standpoint the reactions that are taking place during and after the actual welding operation. Radiographic technique has long been used study and test welds from the standpoint soundness. may even possible estab- lish standards this method. This may particularly true with the broader applications graphic equipment, which the order per cent. This form weld study has been applied particularly determine the quality the welding opera- tion itself, the light weld de- sign and qualifications operators. However, the more stringent en- Investigation Welding Problems Through Metallurgy The rapid advances welding technique which have taken place the last few years are creating need for prompt advancement engineering, chemistry and metallurgy applied welding problems. Presented here discussion metallurgical investigation methods including the microscopic study porosity, micro-cracks, non-metallic inclusions and similar characteristics in- clusions the various parts the weld itself, they affect weldability. gineering demands welded struc- tures are now forcing the situation point where, some airplane applications for instance, the de- mands for soundness weld ap- proach perfection itself cri- terion. When such situations must faced, careful study all the fac- tors involved the entire process may reveal that the demands are such that, with the best operators and technique obtainable, the vari- ations from one heat another the same kind steel from the same mill may cause rejections the material it- self. Fusion types welding combine the extremes the metallurgical conditions metal alloy into one unit which should meet the highest performance requirements. For instance, the parts united may have been either cold-worked heat-treated. either case the metal may materially altered structure and properties the heat the welding process. Never- theless, these pieces are united casting—the weld itself—and the final product often expected meet the requirements the parent pieces. many instances the filler rod used the welding operation entirely different chemical compo- sition than that the parts joined. However, the properties this rod “as welded” should closely approximate the over-all properties the entire assembly. This not only holds true for those instances which the mechanical properties are first importance, but also where the chemical properties (cor- rosion) high-temperature, heat- resisting characteristics are con- cerned. The electrodes filler rods themselves may subject the same erratic behavior that re- ferred above connection with the parts joined. con- sequence this, difficulties become compounded. The highlights recent ex- ample such variations may serve illustrate the importance base material weldability. this par- ticular application, low alloy steel the class, used quite widely automotive applications, THE IRON AGE, October 29, 1942—37 t | | | | | | | | | | | ° ° ° | | | : } | | ° ° ° } | ‘ ‘ q See the junction the weld metal plate weld made per- with the parent stock, resulting from regional hardening. ture which was subjected severe vibratory stresses actual service. Quite obviously, the welded portions had perfect. Difficulty welding occurred, however, al- though the most careful investiga- tion the welding operation re- vealed nearly perfect technique. The difficulty which was being experienced manifested itself certain wildness the molten pool and then the erupting this pool just before solidification, leaving deep pock marks. Examinations made sections through these eruptions disclosed that most them originated the plate the area immediately below the molten pool weld metal. chemical analysis the various heats the steel, and “bad” weldability, failed reveal any consistently tions from the nominal composition. Also, the employment other weld- ing methods substantiated the dif- when spot testing with rod and flame types welding, was noted that given sample the rating behavior from bad good was the order carbon arc, metallic arc and flame type, respectively. Metallurgical Study The analysis all this informa- tion seemed indicate that these obvious differences weldability were due the minor constituents the steel and their reactions dur- ing the welding process. Conse- quently, thorough study was in- itiated, involving such phases complete microscopic examinations, thermal and chemical analyses, grain size examination, carburiza- tion test, and examination for non- metallic inclusions. mit study the micro-structure for visual evidence area hardening. these faulty welds revealed that the causes the wildness the molten pool and also the eruptions which caused the pock marks were def- initely associated with the presence eral kinds and amounts. The erup- tions were found have been sole- caused the decomposition some these inclusions due heat alone, witnessed the fact that the source the eruption was below the bottom the weld pool, ciently plastic give way under the pressure gas generated the break-down. This turn explained the dif- ferences rating weldability— the basic reason being, the concen- tration heat the point weld- ing. The method giving the high- est concentration (arc) apparently caused the most damage. When the information from these heat-affected area adjacent the plate weld showing the narrow zone high hardness between the plate weld (Fig. and the heat-affected zone shown Fig. shown Fig. “> 38—THE IRON AGE, 29, 1942 4 ‘4 a tests was correlated, the result was the presentation clear-cut dem- onstration that the ordinary varia- tions the steelmaking process resulted varying amounts non-metallic inclusions, many which were definitely detrimental the welding characteristics the metal. For example, even though the sulphur analyses were about 0.025 per cent lower, was found that lower sulphur con- tents were needed. The presence sulphides streamer types inclusions poor welding, even steels with these low sulphur contents. Furthermore, soon became ap- parent that, while sulphur could not accused being the sole cause the poor weldability, accurate sulphur analysis could upon give fairly accurate esti- mation the welding properties. Further corroboration evidence one the steel mill laboratories proved the step- ping stone the achievement consistent production steel weldability altering the melting and deoxidation practices such manner “clean up” the heat far more effectively. This same kind trouble has been encountered some the more highly alloyed steels which had behaved erratically welding. One these, bearing some 0.2 per cent aluminum alloying agent, was found have the major por- which persisted coming out the weld, thus causing considerable difficulty. Steels which properties should examined with particular care, for sometimes found that adjacent the area the junction the weld metal and the parent stock there may occur regions hardening (sometimes area) which relieve themselves very fine cracking. These micro- cracks (Fig. may quite readily escape any casual examination the weld. Nevertheless, they are dangerous, for they can easily the cause structural failure the joint. steels which can air-hardened any extent, there will area adjacent the weld that has been subjected the treatment neces- sary accomplish hardening. This action sometimes gives trouble through cracking, but the occurrence usually quite readily detectable ordinary hardness de- terminations. The smaller areas, however, such mentioned above, are frequently missed the usual hardness testing. Thus, examin- ing samples material that may thorough exploration the hard- ness with micro-hardness tester and the micro-structure with the microscope. brought about the welding, well for any additional evidences cracks, nitrides, and oxides, and for micro-hardness. Previous reference was made the presence small areas hard- ening which might overlooked. However, careful microscopic exam- ination the micro-structure may give visual evidence such areas, they may inferred from the metallurgical microscope used both for the visual examination micro-structures and for making permanent photographs these struc- tures for more deliberate study and record purposes. The microscopic examination welds should begin with very carefully polished can thoroughly studied from the standpoint porosity, micro- cracks, the kind, nature, and distri- bution non-metallic inclusions the unheated portions the sam- ple, and similar characteristics inclusions the various parts the weld itself. This latter prime importance for the results studies this kind can fre- quently lead the detection im- proper welding conditions. Following the examination the unetched sample, should care- fully etched, and the entire weld zone thoroughly explored for the structural changes types structure evidence. example occurrence this kind shown the comparison plate weld (Fig. and its ad- joining heat-affected zone (Fig. which had very small area high hardness between them (Fig. 4). These few examples which have been cited should give sufficient evi dence the value making complete investigation each new welding problem from metallurgi- cal viewpoint. The adoption fundamental policy this kind beneficial the immediate prob- lem under consideration; addi- data for application the prob- lems the future. THE IRON AGE, October 29, | : at : ese fe) ° and | ORKMEN move rack Airacobra parts from the quench cabinet, thus com- pleting the heat treating operation for aluminum alloy parts Bell Air- craft Corp. the ceiling the cabi- net may seen the rows special quench nozzles which are used. New Equipment Speeds Aluminum HEN method Dural heat treating work hand, the cost goes up. small production lots comparatively few skilled men are required bring quench, provided there sufficient “ice box” permit even flow from heat treat rework. Bell Aircraft foresaw during 1941 the necessity improving the method and effi- ciency this very important part manufacture the Army P-39 Airacobra. The Dural heat treating furnace (excepting salt type for large work) then used was “car-bot- construction which the bot- tom the furnace rolled away, allowing the rack heat treat parts lowered quickly into quench 40—THE IRON AGE, October 29, 1942 tank underneath. With this instal- lation equipment means was pro- vided take the rack from under the furnace (under water) while the bottom the furnace rolled into place. Then hooks from crane above lifted the rack and unloading position beside the pit. Parts being heat treated were hung wires hooks and often nested rotated when quickly dunked. The result was that many pieces were warped regardless the care the loading men. When more furnace capacity and faster racking and unloading was needed, instead merely duplicat- ing the old installation, studies were made several improved types. time was important essential, was decided con- struct quenching setup somewhat oversize basis insure performance with the thought that later date more economically designed installation could made. The new heat treating unit con- sists the original and one new ft. long box Lindberg furnace. Car tracks laid these furnaces are matched tracks quenching booth which, turn, passes across the door ends the furnaces, acting transfer car. The booth also connects with either two loading and unloading racks which permits bringing load from the furnace through the quenching booth and then through doors the booth the unloading position. The same quench booth then moved the other loading track where rack special truck ~ d ww =a minum alloy heat treating tion. the fore- ground may seen loading racks, and stockpile parts heat treated. the upper center may seen the quench cabinet, with doors open, ground stand the two furnaces used. d Heat Treating transferred the last opened fur- nace for heating. The car which carries the heat treating racks has fall-away mechanism controlled cams and operated roller chain the quenching booth ‘an raised under loaded rack the loading platform, carried through the quenching booth and dropped when place the fur- nace, permitting the actual car truck pulled from under quenching rack. Thus, one car can service two more units this type heat treat and the car itself only the furnace about one- half minute. Because the racks are not sub- ject heavy shocks, the case the discarded heat treating pro- cedure, much simpler construction possible. longer must special alloy steels used; instead, ordi- nary, hot rolled strap steel ade- quate. Construction bolted, in- stead welded, and upright mem- bers are connected chains, in- stead being held rigid con- necting, welded pipes. Rods, with hooks the ends, are loaded with parts and attached the chains the sides the racks. Wire baskets serve the bottoms the racks. These baskets have sides about in. high, and into them are loaded hundreds small parts for heat treating. Because there rough handling the parts during the heat treating process, including quenching, longer necessary fasten each piece securely before, and conse- quently loading and unloading greatly speeded. JAMES WHITELEY Plant Engineer and Draftsman Respectively, Bell Aircraft Corp., Buffalo The first loading operation con- sists filling the basket with small parts, after which larger parts are the rod which, turn, are attached the chains. Once the rack has been loaded, the carrying cart rolled into position, and the rack lifted off the floor lever action. The cycle operations includes bringing the quench booth the furnace door and while door partly raised, sending the truck into the furnace under the rack where the cams cause the truck raise the load, which point the furnace door completely opened and the loaded rack parts drawn into the quench booth. Before the rack drawn into the quench booth, sprays novel, self-cleaning type Bell design are THE IRON AGE, October 29, | n- é 4 ORKMEN load heat- treating rack with alu- minum alloy When loaded, the rack will move through the quench cabinet, seen the rear, into one two furnaces. the floor the rack are wire baskets, used hold small parts. ABOVE ° ° ° RIGHT quenching cabinet used the heat treating aluminum alloy parts. the ceiling may seen the special nozzles used. Other nozzles cated the sides the cabi- net. 42—THE IRON AGE, October 29, 1942 turned on. These sprays are posi- tioned the top the booth, di- rectly the path large, high velocity air blast which carries the fog rapidly downward through un- derfloor ducts. the loaded rack pulled under this cold down draft, the aluminum alloy parts are cooled within matter seconds. When the car brought rest inside the booth, side sprays are turned cool the heavier metal the rack itself, after which the rack drawn out the booth the load- ing platform and the quench booth moved receive incoming, loaded rack. The nozzles used are credited with playing important part the overall success the quench- ing method now used Bell Air- craft. Conventional nozzles, used for such work, would clog repeat- edly tiny particles dirt lodged the orifices, and the quenching apparatus would “down” great deal time, during which the nozzles were removed for cleaning. Consequently, considerable exper- imentation was carried on, first effort adapt the conventional nozzle types the job required, and later the development new type nozzle. The resulting nozzle, now being used, made two main parts, designed that flushed itself automatically twice during each spraying operation. action removes all particles dirt which may have come through the water lines. Pro- vision was made during the design- ing the nozzle obtain solid spray, instead the hollow spray which normally would develop. Suitable cyclones are arranged the underfloor ducts separate the large volume water from the air current before the air passed through and out the roof the building. Sufficient used water, which picks oxides and dirt from the work, drained from water sump and fresh makeup added for succeeding operation. The volume and pressure water for the fog sprays and cooling spray furnished h.p. di- rect connected centrifugal pump while the air blast comes from motor-driven blower like power. The entire installation was made with minimum interruption heat treating service and few un- foreseen difficulties were encoun- tered. With this system, the sus- pended parts are moved while being quenched; hence, after little study methods loading the racks, the greater part reforming due warpage parts has been eliminated. There has been difficulty meeting the strict inspection tests following heat treat and the installation has operated 24-hr. basis since completion, with serious loss time. Worn Reamers Reforged Size ORN reamers having straight flutes are now being reforged back original size the Abra- sive Engineering Corp., Spring Lake, Mich. The resizing ream- bits involves heating the under- sized bits forging temperature and inserting special die. This die, gripping the entire reamer, forces the metal from the shaft out into the flutes what might compared upsetting process. most instances much 0.020 0.030 in. can added the original diameter. the present time, the company’s dies will han- dle reamers from in. nomi- nal size. Special equipment being used for which patents have been ap- plied. This machinery de- signed that the depth the forg- ing print gaged from the surface displace only enough metal in- crease the size the required amount. This operation may several times heavy duty ream- ers. Like other forged tools, the life reamers treated greatly ex- tended. This due the working the material and the increase density obtained. The micro- photographs show the structure high speed steel reamer body part not affected the restoring process and, for comparison, one LEFT TRUCTURE high speed steel body point away from the cut- ting edge and out the field the restoring process. Magnification 500 times. RIGHT TEEL structure taken cutting edge same ream- er, density after restoring original size. Mag- nification 500 times. taken the cutting edge the same reamer after salvaging. The increased density very apparent. The process applicable all straight reamers except inserted blade and expansion reamers. This includes chucking reamers, jobbers reamers, rose reamers, bridge ream- ers and shell reamers. Due the wide variation the pitch spiral reamers, well other factors, has not been possible prepare standard dies for handling this class work. The company re- sizing straight fluted reamers from two three weeks time prorities ranging from A-l-a expected that the size range will expanded below in. THE IRON AGE, October 29, 1942—43 | 4 | { Flame-Priming posed the corrosive effect acid atmospheres usually have, addition rust deposit de- scribed the previous article, mixture acid salts which, being hygroscopic, tend pick and hold moisture. These salts cannot brushing alone, matter how thorough. flame-priming, how- ever, moisture driven out the salts, forming anhydrous, granu- lated salts which can brushed away, leaving clean surface ideal- prepared receive the protec- tive coating. which have been ex- Heat Transfer When the flame-primin