The Iron Age 1936-12-31: Vol 138 Iss 27

31, 1936 STEEL THE SAME HIGH QUALITY THAT YOU CAN EXPECT ALL REPUBLIC STEEL PRODUCTS Butt weld, lap weld and electric weld pipe steel, copper-bearing steel and rust- resisting Toncan Copper Molybdenum Iron —black and galvanized—in all standard weights and sizes. Oil country casing and tubing. Line pipe. Write for literature. ‘ : 4 4 — 2210 Washington Ave. addition adequate stocks, exceptional plant facilities guarantee prompt delivery even the largest orders for Elephant Brand Phosphor Bronze products. delay delivery materials need disrupt your production schedules. Furthermore, reliable, fine quality Elephant Brand Phosphor Bronze made available you forms suitable wide variety applications. Nowhere that corrosion eats the life from metal place where its strong, durable and elastic properties are required need denied the safeguard this versatile metal. Complete information, stock lists and prices are yours upon request. trial order will convince you. THE PHOSPHOR BRONZE SMELTING COMPANY Philadelphia, Pa. FRITZ FRANK President J. H. VAN DEVENTER Editor Cc. E. WRIGHT A. I. FINDLEY Managing Editor Editor Emeritus Machinery Editor Art Editor Metallurgical Editor Associate Editors JURASCHEK Consulting Editor Resident District Editors Washington Chicago Cleveland Detroit Pittsburgh Editorial Correspondents London, England Cincinnati Boston CHESTNUT AND STREETS, PHILADELPHIA, PA. Hamburg, Germany Milwaukee San Francisco Sales Offices SANDERSON ROUNTREE, ALLISON Toronto, Ontario Birmingham Newark, 239 WEST 39TH STREET NEW YORK, Roy TURNER St. Louis Buffalo Con December 31, 1936 The Economics Industrial Power Transmission Random Thoughts Idle Steel Man How Weld Twenty-Nine Metals Automotive Industry ..... Plant Expansion and Equipment Buying......... Owned and Published CHILTON COMPANY Copyright 1936 Chilton Company (Inc.) (Incorporated) Executive and Publication Offices, Chestnut and Sts., Philadelphia, Pa. BAUR, General Advertising Manager DIX, Manager Reader Service MUSSELMAN, President Member, Audit Bureau Circulations ADVERTISING STAFF FRITZ FRANK, Executive Vice-President Emerson Findley, 621 Union Cleveland Member Associated Business Papers Sts.. Philadelphia, Pa. Indexed the Industrial Arts Index. JOSEPH HILDRETH, Hottenstein, 802 Otis Chicago GRIFFITHS. Published every Thursday. Subscrip- Leonard, 239 39th St., New York EVERIT sessions, Mexico, Cuba, $6.00; Can- ada, $8.50, including duty; Foreign Ober, 239 29th St., New York ERNEST HASTINGS, $12.00 year. Single cents. Robinson, 428 Park Pittsburgh WILLIAM BARBER, Treasurer Cable Address, ‘‘Ironage, Warren, Box 81, Hartford, Conn. JOHN BLAIR MOFFETT, Secretary q ; | 1 RON ee | — | | ethlehem Throughout Transportation Steel Plates occupy many important positions throughout transportation and industry. the hulls and superstructures fleet luxury liners and plod- ding freighters—in locomotives and cars many im- portant railroads—in frames and housings for huge machines—in such widely varied structures oil storage tanks, gas holders, barges, the towers the Golden and Industry Gate Bridge. These diverse applications are indications the adaptability and utility Bethlehem Steel Plates. Fully controlled production assures uniformly high quality. Bethlehem’s long experience and complete manufacturing facilities make easy supply the type and grade plate best suited the use for which intended. BETHLEHEM STEEL COMPANY, General Offices: Bethlehem, Pa. District Offices: Albany, Atlanta, Baltimore, Boston, Bridgeport, Buffalo, Chicago, Cincinnati, Cleveland, Dallas, Detroit, Hartford, Honolulu, Houston, Indianapolis, Kansas City, Los Angeles, Milwaukee, New York, Philadelphia, Pittsburgh, Portland, Ore., Salt Lake City, San Antonio, San Francisco, St. Louis, St. Paul, Seattle, Syracuse, Washington, Wilkes-Barre, York. Export Distributor: Bethlehem Steel Export Corporation, New York. 4 _ € Pa BETHLEHEM STEEL COMPANY IRON AGE, December 31, 1936 THE IRON AGE ... DECEMBER 1936 ESTABLISHED Vol. 138, No. Resolved HERE something fascinating about plain white paper. could show you great rolls it, for example, the stock room our printing plant. There lies, quiet and meaningless except paper, but full potential power for useful service. Something like the still waters above the power plant dam which time will become electric current and work for people. Week week, next year, that paper will transformed into record accomplish- ment the metal-working industry. What will be, one can foretell. There will announcements, undoubtedly, many forward steps technical progress; there will important developments employer-employee relations. the plain white paper gradually becomes transformed into history and information, shall know how far the forward steps are outdistancing the backward ones whether 1937 become what hope will be—a year outstanding progress. ‘Here something for you think about this connection. The record that will written those great rolls plain white paper not composed editors printers, written the industry. And every man the industry, laborer president, "takes his pen help write that record. When you think that way, comes home each one us. not think that any man our industry would know- ingly put mark that white paper that would record step backward instead step forward. Nineteen thirty-seven may critical year for all us, domestic well world affairs. Each one us, then, should strive more than ever his best make that white paper unwind record real progress. Let all strive never before fill this record with good will toward our fellow men. are positions authority, let try make 1937 peaceful and happy year for those who come under our direction. And let all try make prosperous year; one that will bring better living for everyone, more opportunity for men work and earn. resolved that each and every one will our utmost make 1937 the best year yet for the metal-working industry and for America. rere | | | ‘ 4 ° ° FRANCIS JURASCHEK Consulting Editor, The Age UMMARIZING the two discussions heretofore published the economics industrial power transmis- sion, the issues Nov. and Dec. 17, this article states succinctly the advan- tages and limitations the two present systems driv- the first paper this series was stated that the real question designing transmission today comes down this question, how many machines shall driven from one motor? This the basis the economic arguments the subject, for fully per cent all industrial ma- chinery now driven, directly indirectly, electric motors. debating this question may leave out the picture for the time being those machines which 20—THE IRON AGE, December 31, 1936 TRANSMISSION ing industrial machinery— individual motor drive and modern group drive and clears the ground for the de- tailed presentations the applicability various types power transmission equip- ment. are driven more than one motor, such certain complicated machine tools with multiple mo- tions different speeds, and con- sider only those machines which may operated one motor one machine (individual motor drive) one motor many machines (modern group drive). Likewise may eliminate all consideration old-fashioned lineshaft drives, the assumption, concurred almost universally, drives are anachronisms today, and should replaced quickly possible for both economic and How Many Machines Each Motor? engineering reasons one the other the modern transmission systems. The slogan “Do Electrically” has been somewhat overworked recent years, with the result that industrial users motors have made many applications small motors which have not been war- ranted economically. But not correct impugn the reliability small motors, for they have won enviable place faithful and thoroughly useful servant in- dustry. There are many situations which they cannot replaced the most efficient and economi- cal means applying power machinery. There are also situa- tions which they should never considered. analysis attempt indicate, first, where individual motor drive, whether with large small motors, the only type drive borderline cases either method possible, why individual motor drive preferred over | / ik —— 4 — i ° ° ° modern group drive; third, in- dicate the great middle ground where individual motor drive and modern group drive really com- pete; and fourth, the types con- ditions under which modern group drive best. the same time, should borne mind that “circumstances alter and hard and fast rules cannot laid down. The best theoretical considerations may upset given set condi- tions. Every application must studied its own merits, from the combined standpoints type service, operating characteris- tics the machine, first cost, operating cost and maintenance cost the transmission equipment, production flow, motion economy, materials handling requirements, safety, lighting and general work- ing conditions. With these mental reservations the problem may approached follows: Individual Drives Certain considerations indicate conclusively individual motor drive meeting the only practical manner particular requirements the machines driven. All machines which are themselves movable, such hoists, cranes, industrial trucks, and portable power tools all descrip- Manifestly would not possible group-drive such equip- ment. (It should noted that many these machines may be, and are, driven other means than electric motors, but electric motors are preferred cases.) When speaking port- able power tools, one’s mind natu- rally turns the electric drill and similar pieces small hand equip- ment. But portable power tool today may mean machine weigh- ing several tons. Fig. several such pieces equipment are shown, working the shops the Westinghouse Electric Mfg. group-driven. This ft. valve section for Boulder Dam was work too large taken stationary machines, portable (post mills and radial drill) were taken the work the Westing- house Electric Mfg. Co. shops. Co. ft. valve for Boulder Dam. The work too large take stationary machine tools, table and the machine tools are brought the work, set and held position bolts passing through the T-slots the floor plates. The tools are post mills and, the background radial drill; all, necessity, individually motor driven. Machines which require ex- tremely large applications power comparison with other machines located nearby; such heavy metal stamping and forming presses (see Fig. 2), blooming mills strip rolling mills, high duty suc- tion blower fans (see Fig. 3), large air ammonia compressors, large reciprocating, centrifugal rotary pumps, cement kilns and certain types special production machine tools, broaches, milling cutters and planers. should noted possible exception, how- ever, that where several similar pieces equipment operate similar time schedules all within very short distances each other, possible and may prove de- THE IRON AGE, December 22—THE AGE, December 31, 1936 2—THIS blanking stamping out motor laminations far the drive problem concerned, and hence fitting subject for individual motor drive. LEFT 3—This Duplex fan installed Virginia Light Power Co. perfectly balanced combination induced draft and forced draft wheels mounted common shaft. single, constant speed motor drives both wheels simultaneously. The controls are sensitive that only individual drive will meet the power transmission problem. sirable group them into single motor driven unit, even though the power demands each are high. not possible say what the limit size single group drive motor may be, though prac- tical considerations maintenance and interruptions due break- down will tend impose certain limitations. f Machines which have highly operating characteris- tics comparison with other ma- chines located nearby, such circular saw, squaring shear, conveyor, hydraulic baling-press, ventilating fan. The “highly individual operating characteris- tic’ may high speed, centrifugal pump, low conveyor (although ex- treme speed step-ups downs may efficiently produced gear-sets, variable speeds variable speed transmissions con- nected constant speed power sources); widely fluctuating varying time cycles operation, drum; intermittent starting and stopping, shear. Among some the special cases coming within this category may also listed machines which are difficult start, tube mill cement plant, loaded with fresh- calcined material and the grind- ing balls; machine which re- quires finely graded adjustable machines which require frequent stopping under severe entailing dynamic braking, regen- erative motor operation, “plug- ging,” such mine hoist; and machines which require rapid ac- celeration from heavily loaded 1G. view taken one the Westinghouse machine shops several years ago when old-fashioned lineshaft drive was considered quite correct. Lighting and safety conditions were re start frequent intervals, such sugar centrifugal. The point emphasized here that the machine which always usually, for one reason an- other, out step with the rest the procession should put class itself and driven in- dividually. Machines which are isolated; that is, situated such locations that they cannot grouped with other machines be- cause the extreme lengths shafting required for mechanical interconnection. special case within this category should listed two more machines, parts one operation, located points some distance apart, but requiring synchronous operation; such the cement kiln and the slurry feed cement Machines which require elabo- rate complicated control in- dividual operations, for which remote control considered de- sirable. the first instance the modern multiple operation turret lathe may cited illustra- tion; the second pump filling water storage tank. The illustrations mentioned above should considered merely typical. The operating char- acteristics each case may well apply many other types ma- chines with similar characteristics. Eliminating the types ma- chines noted the five classes above as, under almost all condi- tions, best served individual motor drive, there remains very large proportion all industrial equipment which, reason service conditions operating re- quirements, found grouped the average industrial plant under either two classi- fications: Batteries similar machines, such automatic screw machines, grinders, knitting machines, weav- THE IRON AGE, 1936—23 ° ° ° ing looms, band saws and mixing kettles. Combinations dissimilar machines engaged progressive manufacturing operations one piece work, such lathe, broach, grinder and drill press band-saw, surfacer, lathe and working mill. Here the great middle ground where individual motor drive and modern group drive both apply. considering the economics the application either system, the factors investment cost, operat- ing cost, maintenance cost, service conditions, machine operating char- acteristics, production flow and mo- tion economy must analyzed for both cases. However, this great middle ground there are certain points which scale favor individual motor drive, aside from these considerations. These should carefully noted and weighed the balance against such advan- tages the modern group drive method offers. They may stated follows: which the loads each are fairly constant and well over per cent full load, and where the start- ing load not greatly excess the normal running load (sew- ing machines garment factory provide good example) modern group drive does not present any particular operating advantage, and individual motor drive meth- ods may easily have the prefer- ence for reasons close produc- tion control. brief, for any pro- duction unit machines, unless the load characteristics the ma- chines indicate the possibility using considerably horsepower drive them group methods than individual motors, the superior economy group drive not clearly apparent, spite the lower investment cost and consequently lower fixed charges. II. plant where great deal overtime work done, involv- ing the use few machines only each production group, unless these machines can logically segregated into special groups and operated group units, individ- ual motor drive preferable for the overtime periods work, and may counterbalance the advan- 24—THE IRON AGE, December 1936 tages gained group operation during normal working periods. III. Where the combination several machines logical pro- duction unit would make neces- sary provide very large group drive motor, practical considera- tions motor maintenance interruptions service caused United States. From the remain- ing equipment reasons expedi- ency may dictate the subtraction those machine tools, wood-working tools, miscellaneous types.of chemi- cal engineering equipment and tain kinds special production machinery into which the manufac- turers the tools and equipment 6—WHERE finely graduated speed control required machine tool, the individual motor drive with variable speed transmission unit ideal. Speed changes are made with ease means Graham transmission. motor breakdown may dividual motor drive preferable. Usually, overhead mounted group motors are seldom installed over horsepower, and floor mounted group drive motors sel- dom exceed 100 horsepower. All the real and possible excep- tions the feasibility using modern group drive methods noted heretofore make somewhat more than one-third all the indus- trial machinery now use the have individual motor drives, leaving the purchaser practically choice the matter when installs them his plant. Allow- ing for such deductions, the net remainder somewhat more than per cent the equipment present operating. very small part this now being driven individual motor drive too great cost and too low power factor. Most still being driven the wasteful, | > “ rs | power-consuming, friction-building drives which our great-grandfathers in- stalled, and which have im- proved only the matter technical equipment. Some this lineshaft driven machinery ought logically individually motor driven; most would amply repay the cost modern group drive installation; all must modernized sooner later. And right here that the real oppor- tunity exists cut production costs. Individual vs. Group Drive the middle ground where in- dividual motor drive and modern group drive really compete, the advantages and limitations each method must carefully studied, not abstract theoretical con- siderations, but practical appli- cations the particular plant, department, section depart- ment question. permit them all being driven single motor much smaller rating than the combined capaci- ties all the motors required for individual motor drive. Included within these savings the differ- ence cost one control and one set wiring against num- ber controls and their wiring requirements. This factor usual- offset, however, the increased cost mechanical transmission equipment required with modern group drive. Operating costs are favor modern group drive driven machines are compactly arranged, the mechanical trans- mission efficient can ob- tained, and the entire drive de- signed keep the total load constantly near the rated load the motor. This operating economy breaks down, however, where many machines operate in- termittently infrequent in- tervals, where long lines shaft- a a View similar Westinghouse shop following completion extensive modernization program. Note the marked improvement general great deal stress has been laid the lower investment cost and fixed charges modern group drive installations. These lower first costs are very real where com- pact groups machines operate continuously simultaneously, and where, such groups, the di- versity factor operation the several machines such working conditions. ing are necessary reach sepa- rated machines, where much overtime work, involving the use only few machines, car- ried on. Maintenance costs not vary greatly today between either method drive, where the drives are well designed, intelligently in- stalled, and inspected frequent intervals. There are records the General Electric Co. files large mills operating 3000 4000 motors, with yearly expenditure for maintenance, including repairs, lubricating oil and inspection, not over three cents per motor, average. And, certainly, modern mechanical ment, with shafts mounted anti- friction bearings and belts high quality, shows maintenance costs that are comparable. Production costs may affected favorably either system. Closer speed regulation each machine claimed for individual motor drive, yet has been shown that for many applications modern group drive gives steadier speed, hence permits the utilization maximum machine speeds with in- creased production and improved quality production. Individual motor drive makes for less whole- downs, but the larger group drive motors are generally more reliable and therefore cause downs. Individual motor drive per- mits remote electrical control machine operations, leaving the operator free observe his work, but remote control now being similarly adapted for group drive operation. The former speed con- trol advantages individual motor drive have today their counter- parts special mechanical trans- mission equipment the group drive system. Machine location and relocation very flexible with individual motor drive, but with group drive shafts hung rectangular stringer systems, mounted the floor, below the floor back row machines, large de- gree flexibility made avail- able the group drive system. Such placement shafting like- wise counters many the argu- ments formerly advanced in- dividual motor drive proponents the matter lighting, safety and general working conditions. And handling systems may planned and installed conjunc- tion with modern group drive set- ups practically easily with individual motor drives. All these factors must weighed pro and con connection with the condi- tions the actual case being studied. Figs. and are shown the visible effects typical shop (CONTINUED PAGE 39) THE IRON AGE, December 1936—25 a 5 | RANDOM THOUGHTS FRANK CROCKARD the second section this article published last week, the author listed number practices which conceivably could cheapen and simplify operations the steel mill the future. this, the third and last section the article, the discussion coke ovens continued, and mention made possible changes blooming mill, bessemer, and open- hearth practice. ° MMONIA sulphate recovered by-product from coke oven gas contributed very important credit during the earlier years the by-product oven. To- day the world productive capacity greatly excess consumptive demands industrial nitrogen. consideration this situation and other important factors relating ammonia sulphate fertilizer, would seem highly desirable find through research method fix- ing ammonia form carrying higher ammonia content, which form would remain stable and non-hygroscopic when mixed with finely ground basic blast furnace slag. The substitution ground slag filler instead the inerts sometimes used would many cases permit the filler act volunteer fertilizer, perform- ing useful function soil im- provement. The use inerts im- poses freight costs and labor charges distribution which re- turn benefit. fully realized 26—THE IRON AGE, December 1936 that the use slag this manner would not panacea; rather suggested material which could return credit through better utilization material frequently wasted. the case acid soils those bordering sourness would very bene- ficial. Sulphur coke can be, and many cases is, reduced washing the coal before coking those cases where the sulphur exists free pyrite marcasite and not largely organic sulphur. After such beneficiation, however, the sulphur content the coke still comparatively Further marked reduction highly desir- able because its great metal- lurgical advantage. That such re- sults may obtained post coking operation known tech- nical fact. Dr. Foxwell (Gas Journal, Jan. 1936) states that ex- periments using stream steam for 4-hr. period tempera- ture 800 deg. C., the sulphur removal was per cent the sulphur content the coke. Using hydrogen for like period 1000 deg. C., the coke lost per cent its sulphur. Smaller but important reductions were obtained when using coke oven gas. The problem therefore one developing commercially prac- ticable process, the metallurgical importance which evident. The economic significance such development perhaps even greater. Large tracts coal are not now metallurgically available because their higher sulphur content. The availability process connection with the more favorable geographic location such coals would make them com- petitive with those more remotely located, greatly increasing the re- serves metallurgical fuels and most significantly affecting costs. The blooming mill with its ac- cessories represents important capital investment. The principal operating costs embracing labor, power and fuel constitute im- portant item total steel produc- tion costs, which are further in- unavoidable scrap losses. The material upon which the mill operates the ingot. Here for number reasons known the may developed condi- tions seriously affecting the fin- ished product. These conditions may develop the mold, the soaking pit, the rolls, the sources may exhibited. Viewed method convert- ing molten steel into the solid form the blooming mill represents very expensive and somewhat complex process. The direct transference liquid steel into rolled product would eliminate many technical difficul- ties, greatly reduce capital invest- ment and decrease costs. The re- cent experiments the German, Hans Bleckmann, seem very prom- ising, also the work French investigators. [Ed. Note: Experiments abroad have been laboratory scale generally using small hand-turned rolls, whereas this country large mills have successfully rolled high-grade steel small lots, both the “Norton” unit back 1891 and, more re- Actual experiments indicated the possibility extracting heat from overheated liquid steel manner producing proper solidification be- tween two internally water sprayed rolls, [Ed. Note: this country internal cooling considered dan- gerous; for cracked roll may result severe explosion.] from which the steel emerged plate material say, in. wide and 0.8 in. thick. After cooling proper rolling temperature, the material worked ordinary rolling mills. The problem such vast economic importance that seems worth rating major project intensive research. Its solution would greatly reduce the produc- tion costs light plates, skelp, sheets and strip which them- selves represent very important percentage total rolled products. quite probable, however, that the development extrusion process would directly indirectly affect other groups finished steel. Oval bars would probably available, some which would finished standard bars, while important tonnage would avail- able rod material for the pro- duction wire. Structural mill products would displaced the placement with forms produced continuous cold forming ing strip material derived from ex- truded plates. The aggregate ton- nage affected would probably rep- resent per cent all rolled products. Obviously, the savings through decreased labor, fuel, power and scrap losses would correspond- ingly great. During the early history bessemer steel was used for many purposes. Its importance de- clined with the growing scarcity bessemer ores, the increasing availability scrap and the trade demand for lower phosphorus steel, based upon the belief that brittleness and decreased ductility are directly proportional the phosphorus content, where such effects are function the car- bon content. This supposition was not discouraged those making only open-hearth steel. Dr. Howe early 1890 stated that the case soft steels the effect phosphorus ductility occurring bessemer steel may very slight and value. probable that the bessemer process may continue maintain important position if, indeed, does not enjoy renais- sance. Capital investment per ton steel produced much lower with the bessemer than with the open hearth. The bessemer admirably adapted the production low carbon steel. Some the distin- guishing characteristics besse- mer steel are, greater stiffness and higher tensile strength with given carbon content, compared with open-hearth steel. Higher weldability qualities, easy machine- ability, free cutting exemplified screw and and greater wear resisting qualities cold-rolled shafting. Adapt- ability the production wire and lap butt weld pipe are well recognized. addition these qualities, comprehensive corrosion tests point strongly the superiority bessemer copper-bearing alloy. These and other quality considera- tions indicate the importance bessemer steel for special uses. Flexibility production out- standing advantage, either with reference monthly production, the readily variable converter charge required meeting mill schedules wide chemistry varia- tion and small tonnage. in- creased percentage bessemer production would also decrease soaking pit costs. The matter increasing bes- semer steel output without in- creasing the bessemer ore require- ments for the production addi- bessemer iron, offers attractive problem. The utilization mill scrap the open hearth has long been ac- cepted the conventional method disposition. Here superb raw material very low phorus and sulphur content, and carrying appreciable amount manganese. deliberately con- taminate such desirable raw ma- terial with the high phosphorus the blast furnace pig iron under all market conditions seems some- what questionable, especially when measured terms net com- mercial results. The use low phosphorus mill scrap 100 per cent burden the blast fur- nace with only such minimum ore additions may necessary regulate manganese content and slag volume suggested. The production blast furnace op- erating such charge would about double that its nominal capacity when using all-ore burden. The iron produced would very high quality bes- semer, since the phosphorus con- tent would substantially less than that bessemer iron now produced. With quality iron available for bessemer use, would then desirable establish and main- tain the most regular and uniform operating conditions. This could part accomplished the use dry blast, which variations moisture content would reg- ulated, thus bringing temperature control within narrowed limits. The use oxygen-enriched blast when commercially available will decrease the amount nitro- gen blown, permitting reduction silicon the iron with corre- fuel savings the blast furnace. The use the turbo blower would helpful more accurately regulating blast pres- sure and volume, highly important factors during the turn down THE IRON AGE, December 1936—27 Re period. Ladle additions from the electric furnace could made the liquid condition, assisting more rapid reactions and greater ingot homogeneity. Such cedure would offer inviting possi- bilities the further exploration the bessemer alloy field, which has been more particularly limited the open hearth and electric furnace. Throughout the life the bes- semer process the heat the con- verter gases has The presence ejecta and the intermittency the operation make the recovery problem more difficult. Utilization the pre- heating scrap for use the converter the open hearth, calcining limestone for use the duplex process may feas- ible points attack. The Open Hearth The development the open hearth has progressed along the usual lines gradually increasing unit size and the refinement accessory details which have con- tributed somewhat decreased fuel charges, lowered maintenance costs and decreased man hours per ton steel. Concurrently has necessitated the installation much heavier cranes and ladles, which periodically deliver greatly increased tonnages requiring rela- tively greater soaking pit capacity for the handling the ingots re- sulting from such large heats. Temperature control during pour- ing has not been aided this practice, while, smaller plants, rolling specifications covering such large heats may not readily available. There has been change the fundamental prac- tices relating the strictly metal- lurgical phases the operation. the open hearth much time spent melting scrap and pre- paring the slag. The preparation, loading and charging scrap rep- resent appreciable part costs and not negligible time element during charging. The scrap heated and melted furnace which not operating the counter current principle and therefore relatively inefficient. The slag could much more cheaply and quickly produced slag making furnace. When both these materials are reduced the liquid state, the slag permitted float upon the the metal bath, 28—THE IRON AGE, December 1936 homely blast furnace gains some semblance grace silhouette. Despite apparatus. More than likely, the next few years will witness changes relative where serves insulator, preventing rapid heat transference the bath. Oxidation occurs rather quiescent slag blanket, largely the plane metal-slag contact. Yet the temperature prevailing, the reaction would very sharp the contacts slag and metal were more intimate. the case the acid bessemer, min., and with the basic bessemer the time not greatly extended. hr. less, while the straight open hearth hr. required. These time differences, well known, are due differences rate oxidation. the converter very rapid because the vigorous action characterising the process. existing practice the speed the duplex dropped the half-way point, while the straight open hearth never starts. That great possibilities favoring increased speed are available indicated the results obtained the plant Ugine Perrin, reported Portevin (THE IRON AGE, 16, 1936, page 19). “It known that this process consists principle vigorous boiling liquid steel with suitable fluid slag. choosing proper slag operation few minutes’ dura- tion any degree refinement which may desired, e., desul- phurization, deoxidation, “This new procedure whereby the refining time greatly re- duced marks revolution the manufacture quality steel, ob- tainable now only the prolonged operations the open hearth the electric furnace. The steels produced are very uni- form and the operators are able procure will any grain size, any extent depth temper and other mechanical characteristics which have been agreed upon for Manifestly the velopment such process sug- | ] | gests greatly decreased costs and capital investment. Piping, segregation and blow holes will occur long steel poured into ingot molds. The big-end-up hot-top ingot has min- imized piping. Segregation will continue until instantaneous solid- ification accomplished, obviously difficult attainment. attacking the problem blow holes, the work has been con- fined largely doctoring ladle ingot mold additions, accom- panied the ever present inclu- sions. Other possibilities relating improvement that pouring vacuo. The idea not new, several patents issued years ago ettest attempts this direction, both ingot pouring and the production castings. While im- proved practice has been claimed, the practice has not, far the writer aware, been extensively followed. Perhaps maintaining many years improvement, the blast furnace still most defective piece dimensions, revamping bell design, possible the blast, etc. vacuum and the relatively high surface tension values liquid steel may account for lack wider development. Casting vacuo may not the only available means mechani- cally liberating least portion the ladle gases. interesting research project would that relating the use step between the ladle nozzle and the ingot mold. [Ed. Note: cen- trifuge capable handling tons per min. molten metal now commercial operation Joseph Samson. Results are very satisfactory, e., high purifi- rapid desulphurization, the centrifugal casting cast iron pipe copious volumes gas are disengaged, which the resulting cast product free blow holes. The centrifugally cast steel gum barrels Watertown Arsenal con- tain visible defects the form blow holes inclusions, the latter being deposited the inner narrow free surface the casting. realized that the conditions obtaining centrifugal castings and that simply centrifuging the metal are not comparable. the centrifugal casting the metal sol- idifies near the temperature which occluded gases are lib- erated, and because the very high pressure gradient the gases are forced centrifugal pressure through the radical thickness still liquid metal the inner sur- face. Nevertheless, there important but indeterminate vol- ume segregated gases, the lib- eration which could reason- ably anticipated such process. Slag inclusions would also brought the surface where they would continue floating. There temperature drop which should assist reducing segrega- tion. denser, more homogeneous steel should result. The possibility attaining econ- omies equaling those afforded the mixer would seem warrant the installation experimental unit. The contributions the various research groups supplied much more fundamental data re- garding metallurgical operations. Especially have they greatly aided developing the alloy which still constitute relatively smaller part the total produc- tion. may confidently as- sumed that their collaboration with the operating department would also result the development improved open hearth methods ef- fecting more particularly the pro- duction the high tonnage groups which would result savings incredible magnitude. this brief and somewhat dis- cursive review important fac- tors affecting cost and practice the iron and steel industry, realized that the list most in- complete. suggest many other elements worthy attention any study relating cost reduction means time and material savings. great interest also are the opportunities afforded the very important group shops, where the replacement obsolete ma- chines those higher speeds and feeds would greatly reduce man hours when accompanied proper methods shop planning (CONTINUED PAGE 39) THE IRON AGE, December 1936—29 pite } . WELD WENTY-NINE ° ° CHARLES JENNINGS Engineer Charge Welding Research, Westinghouse Electric HIS the second instalment the series Charles Jennings, which the collected experience the Westinghouse engineers and welding experts set forth. The first instalment appeared the preceding issue The Age and the third will published the issue January 14, 1937. higher carbon steels presents many problems and most cases the results are non too satis- factory. often possible com- plete joint, but rule they not give good service life. This condition clearly illustrated the unsatisfactory that have been obtained date at- joints. production joints the 30—THE IRON AGE, December 1936 welded joint steels containing 0.60 0.70 per cent carbon, recommended shielded arc electrodes used. Bare electrodes can and have been used, but the results are not satisfactory. For the best results, that the parts preheated least 500 deg. before welding and subsequently heat-treated. Heat-treating temperatures 1350-1450 deg. produce the best results. Mfg. Co. ° Austenitic steel electrodes are often recommended for welding the higher carbon steels. The re- sultant welds have good physical properties, but the fusion zone still hard and brittle. Per Cent Nickel Steels There are several grades per cent nickel steels used for structural work. These grades vary principally the percentages carbon and manganese present. Although the “as rolled” state these steels have pearlitic struc- ture, they will develop martensite the heat effect zone. result, for the best weldability, the lower carbon ranges are preferred. grades per cent nickel steels are given Table IX. TABLE Chemical Analysis 34% Per Cent Nickel Steels Per Cent Per Cent 0.15-0.30 0.05 0.05 Phosphorus ....... 0.04 0.04 | > | Physical Properties Per Cent Nickel Steels SAE-2315 Yield point, 55-60,000 60—65,000 Tensile strength, Elongation, per cent 20-25 20-25 Reduction area, The air-hardening properties these steels may from cracking. Consequently, pre- heating from 200 300 deg. generally recommended. the first pass weld can made with- out trouble, the resultant heating caused will usually allow the joint completed without diffi- culty. Subsequent heat-treatment after welding recommended produce welded joints the high- est quality. Heat-treating temper- atures 1150 1200 deg. are recommended. Bare type electrodes can used these steels with satisfactory results, but the resultant welds are low ductility and inferior the base metal tensile strength. Such welds, will, however, have relatively high strength the re- sult the deposited metal absorb- ing some the nickel from the base metal. Welds this type will ESTING welds important in. plate the bed 2000 ton press. THE IRON AGE, December welding stif- feners pick from 0.9 1.25 per cent nickel. Shielded electrodes produce the most satisfactory results and several types electrodes may used such low carbon, and per cent nickel and molybdenum electrodes. properties the welds will de- pendent upon the electrode used, but almost independent the car- bon content the base metal. The only property that appreciably affected the carbon content the tensile strength which will about per cent higher for the higher carbon grade. Typical physical properties welded joints the “as welded” conditions are given Table TABLE Chemical Analysis Per Cent Chromium Steel 4.0-6.0 per cent 0.40 per cent max. 0.03 per cent max. Physical Properties Per Cent Chromium Steel Yield point, in.......... 35-40,000 Tensile strength, in..... 65-70,000 Elongation, per cent in.... 35-40 Reduction area, per cent.... 65-75 Hardness (Brinell) 130-140 chromium steel are given Table The air-hardening properties this alloy make necessary TABLE Physical Properties Per Cent Nickel Steel 0.10-0.20; Ni, 3.25-3.75; Si, 0.15-0.30; Mn, 0.04; 0.05 Yield Point Electrode In. Bare low carbon.......... 40-45,000 Coated low carbon........ 40-45,000 Coated per cent Ni.... Coated per cent Ni...... 40-45,000 45-50,000 Tensile Elongation Reduction Strength Per Cent Area Lb./Sq. In. In. Per Cent 60-70,000 8-10 5-10 75-80,000 10-15 20-25 90-95,000 15-20 18-25 80-85,000 15-20 20-25 80-85,000 15-20 20-25 Heat-treatment 1150-1200 deg. after welding reduces the hard- ness the brittle zones and makes them more machinable and duc- tile. also doubles the impact strength and lowers the tensile strength about per cent. cases where high impact re- sistance required low tem- peratures, recommended that nickel molybdenum alloy elec- trodes used. Welds made with low carbon steels have low impact strength sub-zero temperatures, while welds made with nickel and molybdenum alloy electrodes de- velop impact values comparable the base metal such tempera- tures. Steels this grade have distinct air-hardening properties even with low carbon contents. the car- bon content increases, the hardening properties increase. Con- sequently, low carbon ranges should always used for welding pur- poses. The addition small amounts titanium and alumi- num diminish and sometimes pre- vent excessive air hardening. result, these alloys are some- times specified steels that are The chemical analysis and physi- cal properties per cent 32—THE IRON AGE, December 1936 use special precautions. Preheat- ing from 300 500 deg. es- sential unless very light gages are being welded. such cases the heat produced welding seems sufficient. This preheating temperature must maintained during welding. Electrodes analysis simi- lar the base metal are generally recommended, although tory results can obtained with 18-8 (18 per cent chromium—8 per cent nickel) stainless steel elec- trodes. Welds made with the lat- ter electrodes will contain greater ductility the “as welded” con- dition, but the hard, brittle fusion zone will not changed. The 18-8 type electrode will found unsatisfactory many cases because the coefficient expan- sion such welds much higher than that the base metal, and because the recommended heat- treatment for 4-6 per cent chrome steels seriously affects the corro- sion properties such welds. Reverse polarity should used when welding this steel and the welding current and arc voltage should somewhat lower than required when welding plain car- bon steels. The recommended annealing process obtain the maximum softness the weld, and heat af- fected zone, consists full an- neal 1600 deg. followed slow furnace cool about deg. per hour until tempera- ture 1200-1300 deg. reached. From this temperature the struc- ture may air-cooled. Satisfac- tory annealing may often ob- tained prolonged heating 1300 deg. followed slow cooling. Long-time annealing temperatures low 900 deg. followed slow cooling have been found produce beneficial results welds made this alloy. Typical physical properties ob- tained 4-6 per cent chromium steel are tabulated Table XII. Cromansil Steels combinations chromium, man- ganese, and silicon alloying ele- ments. The percentage carbon TABLE Chemical Analysis Typical Cromansil Steel 0.12-0.20 per cent 0.4-0.6 per cent 0.7-0.8 per cent Physical Properties Typical Cromansil Steel Yield in.......... 55-60,000 Tensile strength, in...... 80-90,000 Elongation, per cent in..... 20-28 Reduction area, per cent..... 50-62 present greatly influences the weld- ability. Consequently, gen- erally recommended use steels with carbon contents 0.20 per cent less for welding. typical analysis Cromansil TABLE Physical Properties Welds 4-6 Per Cent Chromium Steels with Electrodes Similar Analysis 0.10; Cr, 5.21; Mn, 0.30; Si, 0.20 Yield Point Treatment In. 60,000 Full Anneal 1600°F..... 46,000 Tensile Elongation Reduction Strength Per Cent Area 67,000 or q | q q q | | | TABLE XIV Physical Properties Welded Cromansil Steel 1.20; Mn, 1.04; Cr, .51; Si, .91 Electrode Treatment Low Carbon Low Carbon Annealed Moly. Alloy Moly. Alloy Annealed 1200°F. Yield Tensile Elongation Point Strength Per Cent Lb. Sq. In. Lb. In. In. 45,000 78,000 24.0 42,000 75,000 26.0 60,000 91,000 22.0 56,000 88,000 26.0 steel with good weldability, and the corresponding physical prop- erties, are given Table XIII. Preheating this alloy not required the carbon content below approximately 0.20 per cent, although beneficial large heavy sections. With carbon contents above 0.20 per cent, pre- heating from 300 500 deg. recommended. properties are obtained welds both the annealed and “as TABLE Chemical Analysis Man-ten Steel 0.25-0.35 per cent Physical Properties Man-ten Steel Yield point, sq. in............55-65,000 Tensile strength, sq. in...... 80-90,000 Elongation per cent in...... 25-20 Reduction area per cent...... 40-50 Endurance limit sq. im........ 40,000 welded” conditions. Annealing after welding the low carbon grades not necessary although recommended for plates over in. thickness. Annealing after weld- ing essential for best results from the higher carbon grades. Low carbon shielded-are and bon- molybdenum electrodes are generally used for welding these steels. Bare type electrodes can used, but the results are inferior those obtained with the shielded- arc electrodes. Although low car- bon electrodes can used, the resultant welds have tensile strength considerably below that the base metal. The temperature use after welding 1150-1200 deg. Higher an- nealing temperatures may used, but they are not essential. Higher annealing temperatures produce properties. Typical physical properties ob- tained Cromansil steel are given Table XIV. Man-ten Steel Man-ten commercial steel containing manganese alloy- ing element combination with approximately 0.30 per cent car- 0.20-0.30 per cent are often added improve the corrosion-resisting properties. This alloy contains very good tensile properties combined with high abrasive resistance. The met- allurgical characteristics resulting from the relatively high percent- age carbon are such that air hardening results from welding un- less preheating used. The degree air hardening obtained great- influenced the size the parts being welded. Consequently, when welding thin sections, the in- creased hardness obtained the fusion zone relatively little importance. When welding heavy sections, preheating from 300-500 deg. generally recommended. The fact that this alloy has air- hardening properties makes de- sirable take special precautions when flame cutting. Heavy sections can easily flame cut without danger obtaining surface cracks preheating the line cut pre- paratory the flame-cutting op- eration. Typical chemical analysis and physical properties Man-ten steel are given Table XV. Welds may made Man-ten steel using various types bare and shielded-are type elec- trodes. Bare electrodes produce brit- tle welds with tensile strength considerably below that the base metal. Consequently, their use not recommended high quality joints are required. Low carbon electrodes produce duc- tile welds high quality although they not have high tensile strength the base metal. Alloy shielded-are electrodes will pro- duce welds having physical prop- metal every respect. The welding procedure employ similar that recommended for plain low-carbon steels except that preheating should used heavy sections and cases where the hard fusion zone may objection- able. Annealing 1100 deg. 1200 deg. after welding recom- mended increase the ductility the heat-affected fusion zone and improve the general quality the joint. Typical physical properties welds made Man-ten steel with molybdenum alloy elec- trodes are given Table XVI. Cor-ten Steel Cor-ten steel commercial alloy containing chromium alloying element increase the TABLE XVII Chemical Analysis Cor-ten Steel 0.10 per cent 0.10-0.30 per cent 0.5 -1.00 per cent 0.50-1.50 per cent Physical Properties Cor-ten Steel Tensile strength, sq. in....... 65-75,000 Elongation, per cent in...... 22-27 Reduction of area, per cent...... 40-55 Endurance limit, sq. in....... 45,000 tensile properties with the possible addition 0.30 0.50 per cent copper improve the corrosion- resisting properties. The carbon content this stee