The Iron Age 1941-07-24: Vol 148 Iss 4

CARBON ALLOY STEEL OHIOLOY PLAIN CHILLED ALLOY IRON CHILi ROLLS ROLLS ROLLS OHIO STEEL FOUNDRY CO., PLANTS LIMA, OHIO SPRINGFIELD, OHIO a 3, : f THIS NEW ADJUSTABLE SINGLE TURNING HEAD DESIGNED PERMIT FASTER SPEEDS AND THE USE CARBIDE CUTTERS The job—machining spindle gear from SAE 3150 steel forging. One the difficult parts this job under tough scale with heavy cut. With the new heavy duty Adjustable Single Turning Head providing more rigid setup permit heavier cuts higher speed, the heavy carbide cutters ploughed through scale and metal without damage the cutting edge- Twenty-three minutes’ turning time saved—and less time lost for tool grinding. today’s high speed production, important get the full production capacity built into your Warner and Swasey Turret Lathe. Warner and Swasey modern bar and chucking tools will save many hours both setup and roduction and your operator will less tired the end the day be- cause these tools make his work easier. Get you have your the Warner and Swasey Small Tool Catalog? PRODUCTION not, write today and learn the many from possibilities for increasing tion with these new improved tools. YOUR OLD AND NEW TURRET LATHES Send for the Warner Swasey Tool Catalog FASTER, FOR WARNER SWASEY You CAN TURN BETTER. This tool avai vailable for No. ing capaci slide. equal swing over cross ; | L 7 : JULY 24, 1941 VOL. 148, NO. VAN DEVENTER President and Editor BAUR Vice-President and General Manager Editor News Editor Technical Editor Machine Tool Associate Associate Editor Editor Editor Associate Editor Associate Editor WINTERS Art Editor Washington Editors MOFFETT JAMES ELLIS Resident District Editors CAMPBELL HERMAN KLEIN Pittsburgh Chicago Cleveland Detroit Editorial Correspondents Buffalo Cincinnati FRAZAR CHARLES POST Boston San Francisco HUGH SHARP JOHN McCUNE Milwaukee Birmingham SANDERSON ROY EDMONDS Toronto, Ontario St. Louis LEROY ALLISON Newark, Editorial The Power House Technical Articles Metallographic Examination Metal Cleaning Broaching Operations the New Supercharger Vanes Milled New Gages and Small Features the Assembly Line This Week Washingion the West Fatigue Cracks News and Market Reports News Industry Construction Steel Personals Machine Tool Activity .... Obitucries Non-Ferrous Market The Industrial Pace Warehouse Prices District Market Reporis 100 Sales Possibilities Copyright, 1941, by Chilton Company (Inc.) Manager Reader Service Owned and Published CHILTON COMPANY (Incorporated) Advertising Staff Executive Editorial ond Findley Union Office Advertising Offices Chestnut and Sts. Herman, Chilton Bldg., Philadelphia Hottenstein, Otis Bldg., Chicago Leonard, 100 East 42nd St., New York Peirce Lewis, 7310 Woodward Ave., Detroit Ober, 100 East 42nd St., New York Warren, Box 81, Hartford, Conn. Don Harner, 1595 Pacific Avenue, Long Beach, Cal. Member, Audit Bureau Circulations Member, Associated Business Papers Indexed the Industrial Arts Index. Pub- lished every Thursday. Subscription Price: United States and Possessions, Mexico, Cuba, $6.00: Canada, $8.50; Foreign, year. Single copy, cents. } J 100 East 42nd St. Philadelphia, Po. New York U.S.A. OFFICERS AND DIRECTORS MUSSELMAN, President JOS. HILDRETH, Vice-President GEORGE GRIFFITHS, Vice-President EVERIT Vice-President VAN DEVENTER, Vice-President BAUR, Vice-President WILLIAM Treasurer JOHN BLAIR Secretary JULIAN CHASE, THOMAS KANE CHARLES HEALE HARRY DUFFY | | | 110 116 : 151 | 30—THE IRON AGE, July 24, Machine Made the Measure YOUR Machine When the machine you build mounted the base you buy, the base becomes part YOUR machine. Remember that—the next time you need bases. Pro- tect your reputation. Let the experience and skill Mahon craftsmen match the knowledge your own expert workmen. appreciate the accuracy fit—the smoother, finer appear- ance—and the savings machining costs. Quota- tions furnished from your THE MAHON COMPANY Detroit, Michigan Machine Bases and Many Other Products BE | f q 4 | 4 } JULY 24, 1941 ESTABLISHED 1855 The Power House heart manufacturing plant the power house and the heart the power house the switchboard the control room. here that response immediately made the needs the many diversified departments. Through the master hand electrical control, the power demands machine departments, foundry, forge shops and dozens other centers specialized activity are immediately met with flexibility that complete that becomes commonplace and taken for granted. Control power the cardinal and basic necessity for getting things done. said, take for granted. Yet underneath lies not only adequate organization the physical means distributing power but beyond and above that, its someone who knows what going and what needed from moment moment. Imagine what would happen manufacturing schedule this knowledge and control were lacking. would “haywire” moment. The finest distribution system that would made would utterly useless with the control board. That something for the American people think about con- nection with the progress our defense program. this great program, our critical source power manpower. takes man operate machine. our potential the amount man-hours available this country for making what need. The this manpower and its distribution the necessary activities accordance with their importance correspond what goes the control room power house. crowd too much manpower into one line activity, penalize another. And that other may just vital the outcome our efforts any. Today, the tendency see nothing but munitions. Airplanes and tanks and guns alone never won war. Agricultural machinery with which obtain food feed armies just important motorized army equipment. Gears and pinions and chain drive belts, hardware, electric motors, mechanics’ tools are all part balanced defense effort and essential even though they cannot directly related defense order. have the finest equipment and the best resources the world make more anything than any other people, anywhere. But what lack experienced hand the control room. 2. >- f r- }- 7 / \ “4 4 4 ag 4 = | Each year thousands employees take advantage the Inland general health examination clinic. This clinic vital factor reducing time lost due illness, which least seven times the loss resulting from injuries. When employee enters this modern and completely equipped clinic given thorough physical examination, including blood tests and X-rays. this examination discloses condition indicating chronic disease, further special tests are made. This man then may his doctor with the report the Inland clinic. The diagnosis accurate and complete, and correct treatment can started once. Benefits the Inland clinic are many. Inland employees need not harbor the fear suspected SHEETS BARS Every employee who enters the clinic given thorough blood test. nland Clinic General PLATES TRACK Chest X-rays are important part the Inland clinic examination. disease, their earning power kept more stable, im- proved physical condition makes them and liability accidents reduced. Further, the clinic examination shows employee physically unfitted for his job, kept the payroll trans- fer work within his capacity. Another benefit the relief from mental strain due illnesses home, because Inland employees may take such troubles the for expert advice. This Inland clinic, building the general health level, helps retain their full earning power, provides them with the type work suited their physical condition, and adds many years their work life. This clinic helps Inland keep skilled men the job, and doing makes Inland employees more valuable their families and their community. FLOOR PLATE PILING REINFORCING BARS STRUCTURALS | Dearborn Street, Offices: Milwaukee, Detroit, St. Paul, St. Louis, Kansas City, Cincinnati, New part ING Translated COSMAN The New York ERMANY her present war handicapped the lack raw materials for the metal industries. There acute shortage nickel, for instance, and there general scarcity materials which are usually con- sidered absolutely essential the production high quality alloy steels. This situation has led the development steels which, with the work heavy duty alloy steels. The primary demand this case closer control production and greater accuracy and adaptation testing methods. Diergarten, Eng., head the laboratories the Vereinigte Kugellagerfabriken, G., Schwein- furt, leading ball and roller bear- ing producer, has shown report the Verein Deutscher Ingenieure new system organized testing and reduction the relevant in- formation about material—espe- cially steel—to numbers; this not only facilitates tabulation and correlated investigations, but also inter-departmental collaboration, for instance, between works and laboratories. The following para- graphs describe this very interest- ing method, and, also some the results claimed been achieved the works Schwein- furt. Modern designing requires the engineer shape each part fit etallographic xamination tandardized —The highly interesting study summarized herein ap- peared recently Germany, written Dr. Dier- garten, head the research laboratories Vereinigte Kugellagerfabriken, A.G., Schweinfurth. Certainly there place this country for technique standardizing microscopic testing metals. Perhaps this article can serve stimulant leading collaboration various members the industry, which turn would prove in- valuable producers and consumers alike. its purpose only and avoid all waste. Since, therefore, parts are designed with the strictest material economy, improvements shaping and testing are necessary assure that parts are equal their job. particularly impor- tant probe the homogeneity and fatigue values materials. the choice materials the ultimate ap- plication the part and the sur- face condition are the greatest importance. The surface especially frequently have greater in- fluence than variations chemical mechanical values. For success mass production, product and efficiency manufac- ture; also necessary specify the most suitable material and test continuously its homogeneity and consistency treatment. When the various testing meth- ods are considered, possible arrive broad division class- ing them numerically definable and undefinable. Mechanical and some the physical testing meth- ods (magnetic and conductivity tests) yield results that can ex- pressed numbers. They conform fixed mathematical conceptions, are performed standard way and will useful only insofar they represent stresses and strains that will exerted the material service conditions. Chemical analysis, the other hand, shows permanent quality the ma- terial. indispensable test. Technological testing processes are very useful as-a speedy means checking during manufacture. The visual methods, metallography, ray investigation and magnaflux tests, afford the most useful means interpreting the state ma- terial, assess its usefulness and prescribe treatment which will fit for the job. These visual methods, however, can under- THE IRON AGE, July 24, \ 7 4 IP | ° the me 9 ver, the > ore { = York RITTLE SLAGS, DISSOLVED BALL SHAPE 1.03.1 1.03.2 1.03.3 1.03.4 1.03.5 a 4 1.01.1 j ~ 1.02.2 — 1.01.4 1.02.4 1.01.5 1.02.5 . | | i 1.01.6 1.02.6 1.03.6 SHAPE Slag OVAL SHAPE 1.04.1 1.04.2 1.04.3 1.04.4 1.04.5 1.04.6 LINE SHAPE 1.05.4 1.05. DOUBLE LINE SHAPE 1.06.1 1.06.3 1.06.4 1.06.5 1.06.6 MULTI-POINT SHAPE 1.07.1 1.07.3 1.07.4 1.07. 1.07.6 TANDARIZATION tion inclusions steel. The applica- tion these data will the numerical defini- tion micrographic information concern- ing frequency, kind and shape inclu- sion, and thus con- siderably simplify the classification steels. 100 diam- eters; shown herein one-half size. 1.05.1 . 5.2 1.05.2 1.06.2 ° ° — ° ° 1.05.6 stood only the specialist, and their interpretation needs both theoretical education and practical experience. While certain tests, such the hardness tensile tests, can read off the machine easily and communicated the works figure, visual tests are report and not easy interpret. alleviate this difficulty, stand- ard metallographic series has been designed which expresses visual formation numerically. With the aid this the heat treating shop, can aim certain metallo- graphic number, they are aim- ing certain Brinell hardness. Also, and great importance, fur- ther simplification obtained producer-consumer relations. For some items, for instance inclusions, such standard metal- lographic series (designated herein SMS) has existed for some time, the Fox inclusion count. The present system, however, value because extends this scheme the whole field metallography and shows the way even beyond. judging materials their mi- croscopic conditions should con- sidered. Knowledge steel mak- ing processes and the metallurgical interpretation for subsequent treat- ment will make possible easier and more consistent production high quality parts the steel consuming industries. Precise data are desired for the various materials. The quality steel essentially determined its chemical com- position, but quality within this class depends variety fac- tors: Origin raw materials: Pig iron, scrap, slag. Chemical composition: Percentages Ni, Cr, Mo, etc. Smelting method: Kind furnace, method preparation, method casting. Fabrication: Rolling, forging, pressing, draw- ing, normalizing, hardening, tempering. Further manufacture: Shaping, turning, heat treatment, etc. The most important these the melting method. Distinction between straight carbon steels based the origin from the acid basic open hearth, between alloy steels originating the acid open hearth electric furnace, and be- tween special steel originating the crucible induction furnace. Properties Vary Considerably Steels show fundamental property determined raw ma- terials, furnace and smelting proc- 36—THE IRON AGE, July 24, 1941 ess. Structural alloy steels have better fatigue properties melted the acid open hearth, and silicon- manganese steels have better elonga- tion perpendicular grain flow. The same steel made the basic electric furnace will have ten- fold content. Often there are considerable dif- ferences between casts, which are chemically identical and technically and mechanically equally treated. impossible grasp these dis- tinctions through testing methods other than metallographi- cal investigations. Currently the metallographist highly trained and paid man who should not used perform tions routine testing. But, the 4.00.0 Hardening structure structural and tool steels. 5.00.0 Gray iron, cast steel. 6.00.0 Brass and bronze. 659.0 Aluminum and aluminum alloys. 7.00.0 Other non-ferrous metals. 8.00.0 Surface condition steel and Surface condition other metals. Relations between value numbers and practical results, i.e., behavior the steel during fabri- and use, must obtained through extensive observations and correlations, and tolerances must data for the whole metal working industry should task that can undertaken SMS are set and generally accepted basis for data. This could result the TABLE Time Required for Microscopical Examination Determine Average Slag Content Section Length Section, mm. (width approximately mm.) 120 Time Investigation, Min. When inclusions When inclusions are fine and are coarse evenly distributed and solitary 1.0 1.0 2.0 2.0 3.0 standard metallographic series, SMS, will make possible for the untrained man perform these tests quickly and efficiently, the metallographist being able de- sign and extend series they are needed for special requirements the works. The standard metallographic series has been compiled give information regarding variety properties and the extent which these are encountered the ma- terial. Figures are designed run three groups: The first index gives blanket classification, the second within the group, and the last gives the de- gree frequency volume the occurrence the phenomenon de- fined the preceding numbers. Thus, 1.02.3 means, blanket definition: inclusions; 1.02 spe- cific class: brittle oxide inclusions; 1.02.3 strength frequency referred value number. The selection the system proposed follows: 1.00.0 Slag inclusions steel. 2.00.0 Carbide segregations structural and tool steels. 3.00.0 Normalizing and annealing structure steel (grain size, line structure, etc.). avoidance very wasteful parallel experiments and improvements quality and economical fabrica- tion. Material Investigated Unalloyed structural steels are supplied usually the form bil- lets, booms, slabs, shapes, sheets, strip, etc. The standard (DIN) number (as per instance, SAE) de- fines their quality and composition. These steels are not usually investi- gated metallographically. however, difficulties occurred fre- quently German works during fabrication, these steels were exam- ined metallographically erable detail. Non-metallics were classified according size, kind, and frequency SMS 1.00.0 (See Fig. and grain size was also evaluated and corresponding series established. structural steels were also tested for inclusions, grain size and line structure. They were sup- eter. Free cutting steels came rods mm. diameter from the basic open hearth. order esti- mate advance the cutting prop- erties, tensile strength, hardness, q i | | ij | Wwe elongation and grain size, the dis- tribution and frequency segrega- tional inclusions were taken into account. Steels found retically acceptable the basis SMS proved satisfactory dur- ing fabrication, while steels equal mechanical performance regards tensile strength and hardness, but without metallographic tolerances, were often unsatisfactory vice. Unalloyed and alloyed tool steels, both hypo and hyper-eutectoid, from all steel furnaces, were also inves- tigated for use wide variety tool applications. The ultimate application material determines the degree purity few instances inclusions are desired, weld- ing and spring and free cutting steels; others, slag inclusions are without influence and may neg- lected testing. But, most cases which the steel called heavy duty, slag inclusions must kept low. This especially true for the building parts, the Metal Powders Compressed CCORDING the Hardy Met- allurgical Co., the compres- volves several factors which work against good compression. Among the foremost obstacles are included, (1) the inability metal powders flow freely, (2) the entrapment air gases during compression, (3) the development stratifica- tion planes weakness the compact, and (4) the high com- pression ratios which are necessary due the low density the un- compressed powder compared the compressed object. considerable interest that much has been accomplished overcoming evacuating the powder before com- pression and evacuating the mold into which the powders are pressed. Both the hopper from which the powders flow and the mold into which the powders are fed are partially evacuated. Many production gears, motors, roller bearings, If, for instance, fair sized slag inclusion should get into surface subjected wear, then will break out under pres- sure. The hollow left behind will result stress concentrations and most likely ultimate breakdown the part. Conditiens for the SMS must standardized that repeatable and objective results can obtained. For valid results sufficient num- ber tests must performed. Therefore, from each batch rods certain number are selected which the end pieces are cut off. less than ten test pieces should prepared from one consignment steel uniform quality and di- mension. steel plant, where the position the bars the ingot are known, smaller number tests permissible. Test pieces must hardened obviate mis- takes the processing the test pieces. Alinement the tested surface with the direction de- formation must insured, since otherwise correct estimate the powders which will not flow, which flow but slowly, under at- mospheric conditions, will flow readily when air gases present between the powder particles have been removed evacuation. This improved flow permits the powder fill the mold more rapidly, thus speeding operation. also causes the powder more completely fill the mold cavities and angles, thus making possible the compression more complicated shapes. Avoidance size inclusions made impos- sible. The optimum polished sur- face not required the 100- diameter magnification which the series investigations are per- formed. the operator ciently trained, can estimate both slag inclusions and carbide segregations mildly etched speci- men some steels. magnification 100 diameters was found most suitable together mm. diameter the ground glass inclusions are evenly dis- persed, about min. will suf- fice evaluate the test piece. however, there are solitary large in- clusions, then with the time searching the likelihood finding more will increase—thus, the time search must limited. (See Table I.) Ed. week this ar- ticle will concluded with data SMS evolved bearing in- clusions, segregation, structural phenomena, and sur- face classification. Vacuum serves eliminate planes weak- ness and create greater and more uniform density the finished article. Elimination air and gas reduces the oxidation the metal powders, resulting more rapid and thorough diffusion the powders during the sinter- ing operation. The increased com- pactness powders prior com- pression permits the production higher objects die given depth. The following data appear patent No. 2,198,612: Flow Data: Grams Powder Flowing Through in. Orifice Per Min. Type copper powder Atmospheric pressure: Corresponding 760 mm. both hopper and mold Partial vacuum: Corresponding mm. both hopper and mold 325 mesh 325 mesh 325 mesh 110 none 600 535 410 THE IRON AGE, July 24, 1941—37 ‘ | | most successful methods metal cleaning have al- ways been those which make use the dissolving action reagent the detergent, wetting, penetrating and dispersing prop- erties specially compounded cleaning media. There reason believe that these meth- ods, combined with the obvious mechanical scrubbing action, will ever displaced industrial plants. However, entirely new ap- proach the problem metal degreasing and cleaning cated claims made for new patented material recently em- ployed several industrial plants and offered Kolene Corp., De- troit, under the Kleaner. This cleaner bath catalyzed molten salts. The action this cleaner that oxidizing all the various ma- terials the surface the metal cleaned, the oxidation con- verting these materials into readily removable compounds. action that degreasing, which accomplished the oxidation all carbonaceous matter, oils, greases, etc. This degreasing operation not performed separate one, nor the cleaner designed specifically degreaser, but the action the carbonaceous matter incidental the clean- ing operation which accom- panies. 38—THE IRON AGE, July 24, META CLEANING Kolene Kleaner, using new approach metal cleaning, has met with considerable success removing greases, oils, paints, mill and heat-treat scale, and silica scale, oxidizing all these materials the surface the metal, the oxidation converting them into readily re- movable compounds. ° ° SHERMAN Detroit Editor, The Iron Age ° The second action, simultaneous with the first, the conversion materials the surface, including mill scale scale, which are relatively insoluble many cleaners, into very readily soluble materials which can re- moved mild acid bath. This action accomplished through ap- plication the well-known that the oxide any metal con- taining the most oxygen more soluble than oxides containing less oxygen. most instances with this cleaner, this exactly the re- action that takes place. Taking, example, magnetic oxide iron, which the thick middle layer mill scale (and highly resistant attack even sulphuric acid) the reaction follows when the cleaner ap- plied: ° The resultant compound one dissolvable and there- fore more easily removed from the metal. similar reaction sible with the cupric oxide some- times found copper parts: The two foregoing examples are (virtually more soluble. CLEANING CAST IRONS: Another aspect the use this new cleaner presented the cleaning cast surfaces which normally have them much silica that plating coatings any sort are extremely difficult apply. this case the reaction with the cleaning material HIRTY-FIFTH Series Articles the Technical and Economic Aspects Metal Cleaning and Finishing | | it | one the pos- ome- are ower are are the faces tings ficult ction convert the silica silicon dioxide, which soluble the cleaner. The present general practice acid pickling exposes other ma- terials such phosphorous, sul- phur, carbon and silicon because the severe action the acid the metal itself. Where these are pres- ent, the Kolene Kleaner said oxidize the phosphorous, sulphur and carbon into vaporizable oxides. addition the action oils and greases, mill scale and silica, etc., the cleaner said have similar action welding flux and welding scale and makes possible remove them readily from the surface metal parts. Buffing and polishing compounds, sometimes found difficult are treated the same way this new method. The Kolene mixture salts operative between 550 deg. and 600 deg. F., which temperatures the salts form clear green liquid. The carbonaceous dized this liquid the degreas- ing stage are all converted into vaporizable oxides which pass off taminating the bath. Hydrogen freed during some the reaction passes off steam. stated that the other cleaned from the metal are con- verted into extremely soluble oxides and are removed short mild acid pickle. The degreasing action complete evidenced the absence water break the cleaned metal. present conditions pickle for considerable time acid remove impurities which are relatively in- soluble, the base metal also at- tacked, exposing insoluble materials from the metal itself which show the surface black smudge, commonly pickling smudge. The new cleaning method makes long pickling unnecessary, smudge. When necessary will even remove smudge pickled pieces. EMBRITTLEMENT Another feature the absence hydrogen embrittlement and similar parts which acid pickling sometimes produces, due the release hydrogen installation showing two Kolene Kleaner pots heated gas flames and insulated against heat loss. unfinished metal pot, not insulated yet, can seen the right foreground the picture. the left the raw test piece covered with mill scale. the center piece after immersion Kolene Kleaner with the mill scale converted high oxide soluble material. itself this reported satisfactory paint base for some purposes. the right, the lower half the specimen was immersed Kolene Kleaner the mill scale was made soluble, and the entire specimen dipped per cent hydrochloric acid for can seen that the acid did not affect the upper half the sample, but thoroughly cleaned the lower half dissolving the material it. during the pickling action. The ab- 100 hr. salt spray and com- sence hydrogen embrittlement pression testing machines have after use this cleaner at- been accomplished without failure tributed the short time required the metal. Because the cleaner the acid vat. Lock washers are readily provides for the quick among the parts which are being removal all types buffing cleaned with this method and tests compounds, the less soluble com- THE IRON AGE, July 24, 1941—39 iron samples, coated with low-tin-lead alloy. The one left was pickled acid the accepted manner, while the one right was subjected the recommended procedure for Kolene Kleaner. removal shown these illustrations which depict (at left) piece painted license plate ready for immersion acid after the Kolene Kleaner has oxidized the finish. the right, the cleaned piece metal shown after sec. the per cent hydrochloric acid. pounds (sometimes lower cost) can used when desired. Besides the evidence complete cleaning given the absence water break, practical proof offered the readiness with which metal cleaned can coated with 40—THE IRON AGE, July 24, very low tin alloys, compositions with high per cent lead having been used with remarkable success. This cleaning provides means improving other finishes such galvanizing, cadmium, paint, ete. Pots made carbon steel boiler plate any desired are used for the operation. Heat- ing any conventional means can employed and most cases the pots are sheathed against loss heat. Vents are usually provided above the pots carry off excessive fumes from the impurities, such oil and grease, but the fumes are said and non-corrosive, The compounds formed the cleaner (without any subsequent acid pickling bath) may em- ployed paint base. Such com- pounds, being the sible oxygen content, cannot oxi- dize further and therefore, are themselves fairly ings. the same time, the oxi- dizing effects the bath make suitable paint remover, shown one the photographs. Some typical applications, illus- saving, are shown herewith: Welded Pipe—Mill welded pipe and the line weld- ing flux around the has been problem the pipe indus- try. Cleaning has frequently been accomplished with alkaline wash for min., followed rinse, 2-hr. pickle inhibited sulphuric- hydrofluoric acid (10 per cent 180 deg. F.), then second rinse, alkaline neutralizer bath and third rinse; total time 125 min. The Kolene procedure only 10-min. immersion, rinse, min. the cleaner, then rinse, and min. acid again; total time min. addition, the Kolene procedure cuts out degreasing operation which becomes unneces- sary. Iron Castings The original process calls for sand blast, fol- lowed pickling for hr. sulphuric-hydrofluoric acid. The Kolene process has been set for 5-min. immersion the Kolene Kleaner, treatment with the same acid above for min., reim- mersion Kolene for min. and 15-sec. (approximately) dip hydrochloric acid. The material described article new cleaner not similar the Kolene chlorinated solvent previously the market and still used for some applications. | j | hape the are from and the juent em- com- pos- OXi- are coat- illus- time weld- has ndus- been wash rinse, rinse, ind min. for and time asing ginal hr. The for same reim- and imilar olvent still ture may classified sev- eral ways—perhaps the sim- plest method with respect whether not the temperature accompanied color visible the naked eye. dark room barely possible distin- guish faint dark red color about 900 deg. F., whereas this “lowest temperature” which just possible observe becomes higher more outside light enters the room shop. For general pur- poses, however, that for the aver- age shop, may considered that temperatures below 1100 deg. will not show color, while tempera- tures above this point will ac- companied increasing degrees color. Thus, the temperature scale may arbitrarily divided into the following: Black heat range—below about 1100 deg. Red heat range—above about 1100 deg. The worker the metal field increasingly being tions the producers various materials and their technical divi- sions, and his engineers and his supervisors, which called upon control temperature within fairly close limits. The ever greater demand for control the black heat range, for in- heat for welding. great many cases impractical use ther- mocouple and pyrometer, since the ack Heat Temperatures —Preheating for welding steel, cast iron, and non- ferrous metals; local heat treatment and hardening—all these operations and many others should have careful temperature control. Herein are data metal analyses, temperatures necessary, and novel method gaging such temperatures. LLOYD The Age, New York former should peened into the work and this requires time well the use special equipment. When necessary determine whether certain maximum tem- perature has been exceeded whether certain minimum has been reached, one the best meth- ods making such determinations known Tempil Tempilstik. The Tempil method consists the use thermometric pellets which melt stated and convenient tem- peratures, thus 200 deg. F., 250 deg. F., 300 deg. F., etc., 1600 deg. They are available deg. steps the range 100 deg. 325 deg. F., and deg. steps from 350 deg. necessary place the pellets upon against the heated object. great many cases the heating done locally with torch burner, where required heat but particular part the entire piece. This the case when hot- bending aluminum tubing. Because aluminum extremely weak the upper end the black heat range, the worker must careful not overheat. number uses suggest them- selves for the simple Tempil method temperature control. This dis- cussion concerned primarily with the following operations for vari- ous metals, which temperature control the black heat range necessary Steels Preheating for Welding: General discussion. Preheating plain carbon steel: Carbon molybdenum steels. Other low alloy steels. per cent Cr-Mo and per cent Cr-Mo steels. High chromium nickel austenitic steels. Joining dissimilar compositions. Surface Welding: General discussion. Hard facing. Overlaying for corrosion resistance. Torch and Flame Cutting: Conditioning Semi-Finished Steel: Heat Treatment: Local stress relieving. Determination when remove work from furnace, etc. Straightening Armor Plate: Local Heating and Cooling: Bending. Shearing bar steel. hardened parts. Shrinking one part upon another. Reconditioning stil! tubes. Repair welding costly dies. Cast Preheating for Welding: Plain cast iron. Alloy cast iron. Ni-Resist. THE IRON AGE, July 24, y : ° ° ° ° ° ° Tarring Cast Molds: Tarring Cast Pipe: Non-Ferrous Metals Preheating for Welding: Aluminum Monel Nickel Inconel Copper Zinc Magnesium Brazing and Soldering: Heating for Fabrication: Aluminum alloys. Magnesium Steels Preheating for Welding: The tremendous stimulus which was given metal fabrication the cent origin that well known all workers the field. Because welded joints are consistently stronger than those formed the older methods joining, was natural that welded parts would used under conditions higher stress. This, however, has made necessary insure that welds free objectionable defects such porosity, slag inclusions and cracks, since obvious that welded joints are perform satis- factorily service, they must sound, and generally equal least, properties the base metal. far the most insidious defect welded joint crack. This holds true whether cracks are large small, since under many condi- tions service, small cracks will grow with eventual sudden failure the section. One factor which common many steels their tendency air-harden when cooled rapidly from high temperatures. The de- gree which the various steels will air-harden related primarily the particular composition involved and the rate cooling the va- rious locations the welded joint. generally true, but not with- out some exception, that the greater the air-hardening steel during welding the less the duc- tility and shock resistance mea- sured bend, hardness, and im- pact tests upon the welded joint. Obviously, the greater hardening tendency given steel, the greater the danger crack- ing during and after welding. The control the air-hardening tendencies steel welding usually sought two ways. some cases possible alter the minimum will 42—THE IRON AGE, July 24, 1941 take The most common method, however, control the rate cooling during the welding, the great majority cases the engineer has little choice with regard composition, since par- ticular material selected represents the best compromise be- tween economy and the suitability the material for particular ser- vice. Quite often when at- tempted change composition, the service characteristics material are also affected undesirable degree. natural, therefore, for the eliminate the possibility the for- mation cracks welding controlling the rate cooling the welding operation. This suc- cessfully carried out today the operation known preheating which the parts welded are heated before welding some pre- determined range temperature, result which the rate cooling the welded joint will considerably retarded. metallurgist’s viewpoint the slow- ing down the cooling allows cer- tain microscopic changes take place which yield softer and more ductile structures. There are number factors which affect the hardening characteristics steels. previ- ously stated, composition and rate cooling are prime factors. Others will considered later para- graph. Preheating prime necessity welding great many steels. Dr. Theisinger, well known welding au- thority, expreses the importance preheating excellent summa- tion, thus: “In the actual welding procedure, there one additional precaution that not only helpful, but practi- cally essential: Some heat should introduced into the prior welding and maintained until the completion the joint, especially unheated shops the not recommended cure-all, but whenever some trouble encoun- tered welding, the source which may difficult find, the first attempt correcting the diffi- culty should the introduction some heat into the vessel.” Henry and Claussen point out: “It important that the part preheated the correct tempera- ture there are occasions when too high preheating temperature may disastrous too low; for example, complicated part with- out internal strutting may collapse, the heat from the part may prej- udice the operator’s ability pro- duce sound weld.” 300 deg- . Tempilstik 200 chalk-like emp remains | i | | i ling rate hers ara- sity Dr. au- ma- ure, tion mended for preheating temperatures for welding various steels. present this information available scattered technical articles and the files private laboratories large organizations. the following paragraphs at- tempt made review part the literature. Preheating before welding should practiced for the following rea- sons: (a) Eliminates lessens the danger formation cracks. Minimizes hard zones. (c) Minimizes shrinkage stresses. (d) Lessens Preheating need increased with any steel the following factors are changed: The larger the mass being welded. (2) The lower the temperature the piece being (3) The lower the atmospheric tempera- ture. (4) The smaller the weld rod diameter. (5) The greater the speed welding. (6) The more complicated the shape and design the parts being joined. (7) The greater the difference between the mass the parts being joined. (8) The higher the carbon content the steel. (9) The higher the manganese content the steel. (10) The more the alloy content the right has 300 deg was not reached (11) The more the alloy content air- hardening steels. (12) The greater the air-hardening ca- pacity the steel. Preheating Plain Carbon Steels: general may stated that the plain carbon steels with carbon contents below 0.20 per cent not require preheat unless the sections being welded are large. such 200 deg. minimum mended. the carbon content raised, the need for preheat im- perative and judgment should used based the factors listed above. When carbon content above 0.35 per cent, the steel con- weld but with proper preheating temperature, sufficiently high, and immediate stress relief, cracks should result. Carbon Content Recommended Steel, Preheating Per Cent Temperature Below 200 deg. minimum 300 deg. F., prefer- ably 500 deg. 0.80 least 500 deg. es- sential, somewhat higher preferred Preheating Carbon-Molybdenum Steels: steel commonly used where somewhat higher strength required elevated temperatures than can obtained with plain carbon steel. Thus, this composition largely used for high temperature steam piping, the majority which contains 0.10 per cent carbon. Occasionally, forgings and castings are used with carbon contents 0.35 per cent. Carbon-molybdenum steel should always preheated, but the pre- heating temperature should con- siderably increased with higher carbon contents. Carbon Content Recommended Steel, Preheating Per Cent Temperature minimum minimum minimum Preheating Other Steels: this group falls great many compositions which contain varying amounts the elements chromium, nickel, molybdenum, va- nadium, tungsten, manganese and silicon. Obviously, not possible give all the individual composi- tions here. All these steels should preheated before welding for safest procedure. The higher the carbon content, the greater the danger crack formation and hence the need for high preheating temperatures. The factors previ- ously listed discussing the need for preheating should reviewed before welding these steels. excellent resumé the weld- ing nickel containing alloy steels will found the International Nickel Co. bulletin, “The Working The following table taken there- from: S.A.E. Carbon, Preheat Number Per Cent Temperature 2015, 2115, 0.25 max. 300 deg. 2315, 3115, minimum 4615 2330-35 0.20 0.50 300 deg. 600 deg. minimum 2340-45 0.25 0.50 300 deg. 600 deg. minimum 3215, 3125 0.30 max. 200 deg. 400 deg. minimum 600 deg. 800 deg. minimum 3130-3140 0.25 X3140, 3230 0.45 max. 3145-50 0.20 900 deg. 1100 3245-50 0.55 max. deg. minimum 3325-40 3240, 3435 3450 4620 0.25 max. 400 deg. 800 4815, 4820 deg. minimum 4340-45, 0.35-0.50 400 deg. 900 X4340, 4640 deg. minimum The Metal Thermit Co. recom- mends the following preheating THE IRON AGE, July 24, 1941—43 emp © =] | f. ett has ined the but the era- hen for ith- pse, temperatures for the following low alloy steels: Steel Preheat Temperature Cromansil 300 deg. 500 deg. minimum Man-Ten and 300 deg. 500 deg. Sil-Ten minimum Chrome 300 deg. 500 deg. vanadium minimum Manganese 300 deg. 500 deg. vanadium minimum Copper 200 deg. 300 deg. bearing carbon grades Copper molybdenum Preheating Per Cent Chrome- Molybdenum and Per Cent Chrome-Molybdenum Steels: These steels are commonly used the petroleum refinery because their superior corrosion plain carbon steels. wrought material the carbon content will seldom exceed 0.15 per cent, but castings this element may run high 0.25 per cent. Recom- mended preheating temperatures are given below: Preheating Analysis, Per Cent Temperature 2.00 Cr, 0.5 Mo, 0.15 400 deg. minimum 2.00 Cr, Mo, 0.15 500 deg. minimum 2.00 Cr, 0.5 Mo, 0.15 0.25 500 deg. minimum 2.00 Cr, Mo, 0.15 600 deg. minimum 5.00 Cr, 0.5 Mo, 0.15 deg. minimum 5.00 Cr, 0.5 Mo, 0.15 700 deg. minimum Preheating Plain High mium Steels: These compositions are used primarily environments where the high chromium contents give excellent corrosion resistance certain media. Preheating Analysis, Per Cent Temperature chromium steel 300 deg. 500 deg. minimum chromium steel 300 deg. 500 deg. minimum chromium steel least 400 deg. min. Preheating High Chromium Nickel Austenitic Steels: gen- eral rule these steels not require preheat. Preheating When Joining Steels Different Analyses: often necessary weld two steels dif- ferent analyses. such case the preheating temperature should determined that the composi- tion which requires the greatest preheat. few typical examples are given below: Preheat When Joining Temperature S.A.E. 1040 600 deg. minimum S.A.E. 1020 18-8 carbon-moly deg. minimum steel 44—THE IRON AGE, July 24, 1941 Surface Welding: excellent discussion upon this subject ap- pears the American Society for Metals, Metals Handbook. While this discussion refers primarily the deposition hard metal which pointed out that surfacing may employed deposit metal for corrosion resistance. The fol- lowing quotation from the above articles refers preheating: “The same general rules apply preheating before hard facing apply most welding operations. Parts are always preheated cases where the application the hard facing alloy would otherwise cause them warp check, where time and cost can saved pre- heating. Steels having 0.40 per cent carbon should usually preheated. The optimum temperature heating dependent upon the size and composition the part, but usually between 700 deg. 1200 deg. For certain classes electric arc welding preheat from 350 deg. 450 deg. de- sirable.” Torch and Flame Cutting Steel Both the Metals Handbook and the Welding Handbook contain de- tailed chapters upon this subject. Preheating employed for two reasons. First, requires consid- erably less the cutting gases when the steel has been preheated. Secondly, higher carbon and al- loy steels preheating used pre- vent cracks the cut edges. general rule steels containing less than 0.30 per cent carbon can cut without difficulty preheat used. However, sections are massive and work done cold heat above 200 deg. for safety, regardless composition. Higher carbon steels alloy steels should always preheated before cutting the temperature range from 500 deg. 1000 deg. F., de- pending upon mass and composi- tion. When removing risers from castings high carbon alloy steels, the same preheating temper- atures recommended above should used; per cent chrome-moly steel castings should preheated about 900 deg. before removing risers. High man- ganese steels should also heated for best results. The follow- ing excerpts from the Welding Handbook article are instructive: greater for the heavier sections than for the lighter sections and becomes requirement when high carbon alloy steel heavy sections are cut intricate shapes. With such shapes having acute gles where high stress concentra- tion will involved, particu- larly desirable preheat.” “Preheating accomplishes useful purposes: “First: Preheating increases the efficiency the flame cutting oper- ation reducing the amount oxygen required make the cut. “Second: reduces the tempera- ture gradient set the cutting operation. This turn reduces gives more favorable distribution the cooling stresses and, thereby, prevents the formation quench- ing cooling cracks. “Third: reducing the rate cooling the cut surface does not be- come hard. “Fourth: The temperature differ- ence between the cut face and the body the metal being less, there less carbon and nickel migration towards the surface.” practice the temperature used for preheating varies from few hundred degrees about 1300 deg. preheating temperature most employed ranges from about 600 deg. about 1100 deg. Heat Treatment Steel often necessary carry out local heat treatments many cases this dictated rea- sons economy. great many specifications required that careful heat treat- ment followed with respect the temperature the steel when either inserted into removed from the heat treating furnace. draw, but specifications state that the steel must cooled below some such temperature 500 deg. before being replaced the heat treating furnace. also often required furnace cool some pre-determined temperature before removing the charge from the fur- nace. For accurate work Tempils are very useful, since when the fur- greater than the charge, particu- larly the pieces are massive. Thus, furnace thermocouple may read lower than the pieces being cooled and harmful results might had the charge were removed too soon. Local Heating and Bending The bending forming steel ciently mild that not neces- sary heat the red-heat range. Since air hardening alloy steels takes place above temperatures the vicinity 1400 deg. im- portant not exceed this tempera- ture subsequent heat treatment nee tior ges the out ten hig tim Jul cul clu the tal | i lit lil | | need for highly increased produc- tion for defense purposes, sug- gested that manufacturers review their fabrication processes de- termine the possibility carrying out some the operations lower temperatures, which now require higher temperatures with longer time involved and greater cost. Shearing Bar Steel: Henderson, Jr., the IRON AGE, July 18, 1940, discusses the rough and broken condition sheared ends and bars and his investigation culminated remedy. His con- clusions state that certain tempera- tures are avoided relating the carbon content. The following table taken from Mr. Henderson’s article listing temperatures which pronounced breakage like- occur when bars are sheared near these temperatures: 0.12 per cent carbon 530 deg. 0.38 per cent carbon 570 deg. about 0.85 per 600 deg. cent carbon 620 deg. 0.85 per cent carbon 530 deg. Above 0.85 per cent 600 deg. carbon 620 Straightening Steel Parts: often required pro- duce high degree flatness hardened steel parts after quench- ing and drawing heat treatment. Since hard steels possess relatively little ductility room temperature and since this ductility usually in- creases considerably tempera- tures somewhat above atmospheric, the practice straightening hard- ened steel parts attempted where necessary some slightly elevated temperature. Here the worker finds himself quandary. would like heat high tempera- ture possible minimize the danger crack-formation. the other hand, the straightening temperature too high, the hard- ness the part will lowered with probably early failure ser- vice. general, may said that any hardened steel part may re- heated for straightening any temperature below that which the part was drawn tempered. Thus, steel reamers broaches may heated 300 deg. F., which heat there little danger cracking, whereas the straightening done room tem- perature considerable possibility cracking exists. Armor plates, par- ticularly the non-homogeneous type, are liable contain considerable “bow” after heat treatment. These steels have high degree elas- ticity, but will found that re- heating some temperature below the drawing teniperature will lessen the danger crack formation straightening without appreciably affecting the hardness. Shrinking one Steel Part upon Another: Better control the fit and minimum residual stresses will result temperature con- trolled during this work. the use Tempils, for instance, possible heat either locally out- side furnace with resultant economy and good temperature trol. Repair Welding Costly Steel Dies: The life costly steel dies may extended many times proper repair small cracks checks other defects when they are first observed. consists depositing metal from self-hardening analysis welding rod. Because the die steels are usually extremely hard, advisable preheat carefully before welding. Temperature control preheat very useful that the hardness will maintained the finished repair without the presence weakening cracks. Reconditioning Refinery Still Tubes: well k