The Iron Age 1939-02-02: Vol 143 Iss 5

FRANK President J. H. VAN DEVENTER Editor Managing Editor News Editor Machinery Editor Art Editor Metallurgical Bditor FINDLEY Editor Emeritus Associate Editors PHAIR F. JURASCHEK Consulting Editor Washington Editor MOFFETT Resident District Editors Pittsburgh Chicago Cleveland Detrott Correspondents London, England Cincinnatt FRAZAR Boston Hamburg, MEYER CHARLES Post Milwaukee San SANDERSON ASA ROUNTREE, JR. Toronto, Ontarto Birmingham Newark, N. J. St. Lowis TURNER, Ruffalo Owned and Published by CHILTON COMPANY (Incorporated) Editorial and Executive Offices West 39th New York, N. Y. Publication Office Chestnut and 56th Philadelphia. Pa. OFFICERS AND DIRECTORS MUSSELMAN, President FRITZ J. FRANK, Executive Vice-President FREDERIC C. STEVENS, Vice-President JOSEPH HILDRETH, Vice-President GEORGE H. GRIFFITHS, Vice-President B. TERHUNE, Vice-President WILLIAM BARBER, Treasurer JOHN BLAIR MOFFETT, Secretary JOHN VAN JULIAN CHASE, THOMAS 1L.. KANE, CHARLES 8. BAUR, BAUR, General Advertising Manager DIX, Manager Reader Service Member, Audit Bureau Circulations Member Associated Business Papers Indexed in the Industrial Arts Index. Published every Thursday. Subscrip- tion Price: United States and Pos- sessions, Mexico, Cuba, $6.00; Can- ada, $8.50; Foreign, $12.00 a year. Single copy, cents. Cable Address, ADVERTISING Emerson Findley, 621 Union Bidg., Cleveland B. L. Herman, Chilton Bldg., Phila. H. K. Hottenstein, 802 Otis Blidg., Chicago H. E. Leonard. 239 W. 39th St., New York Peirce Lewis, 7310 Woodward Ave., Detroit * Ober. 239 W. 39th St., New York 498 Park Bldg., Pitts. D. C. Warren, P. 0. Box 81, Hartford, Conn Square Pegs, Round Holes Fabricating Stainless Steel Effect Chromium and Silicon Cast Annealing Cold Rolled Strip Unit Cooling Pits Pulverized Coal Metallurgical Furnaces Design Advances Motors, Controllers and Lighting Furnace Brazing Cast the Assembly Line NEWS CONTENTS Statistics Metal-Working Activity .......... Weekly Ingot Operating Rate Rate Activity Capital Goods Plant Expansion and Equipment Buying New Industrial Literature Just Between Two Products Advertised Index Advertisers Copyright 1939 Chilton Company (Inc.) Contents FEBRUARY 1939 Ryerson certifies the known uniform high quality all steels stock. assure satisfactory heat treat- ment response and year after year uniformity the Alloy Steels, new unique plan has been developed. Whole heats each alloy are that will give the best general results under heat treatment. They are then tested for heat treatment response and data sheets are prepared. Complete information (chemical and physical analysis, grain size, cleanliness rating, and the results heat treatment tests) sent with every shipment—a service never before attempted any steel service company. Let tell you the complete story Ryerson Certified Steels. Write for booklet N5. JOSEPH RYERSON SON, Inc. Plants at: Chicago, Mil- waukee, St. Louis, Cincinnati, Detroit, Cleveland, Buffalo, Boston, Philadelphia, Jersey City. Never Before Attempted... When Ryerson Certified Alloy Steels are placed stock, special data sheets are pre- pared. The one above for the higher car- bon steels. The chart shows actual heat treat- ment results. The heat treater knows exactly what the alloy and exactly how for best results. 28—THE IRON AGE, February 1939 | } ene Jos Pare | | | THE IRON FEBRUARY 1939 ESTABLISHED Vol. 143, No. Square Pegs; Round Holes HAD interesting experience few weeks ago which emphasized the fact that the world not large after all and also that strange things happen the people who inhabit it. The occasion was visit the plant one largest aircraft con- cerns. was, you might expect, busy place. Several thousand men and sev- eral thousand the finest machine tools America were busy turning out product—aircraft engines—which probably the acme all modern precision products, bar none. Instrument making mass production basis the nearest that one could think of. Naturally plant this kind has some pretty high grade people managing it. The production and engineering problems encountered this sort work call for the best talent that can had. was interested meeting these people and talking with them and particu- larly with one gentleman his early 40's whom will call Mr. yes, know Mr. Van said when introduced, "in fact worked for him some years ago." That was news me, for did not recollect it. Which was quite understand- able, perhaps, since Mr. had worked for only few days. did not take longer than that find out that this young engineer was square peg round hole insofar the publishing business was concerned. had persuaded him seek other pastures. tell just what size wore. asked him what position occupied. I'm the chief replied. Believe me, that was surprise! Eighteen years not such long time, but can bring about plenty changes. certainly had the case friend Eighteen years had transformed him from third rate editorial cub top place the engineering profession. That just goes show what happens when you match the pegs and the holes. What great thing would did not have leave much that chance. sat alongside Mr. all through dinner and did not seem have any hard feelings toward for getting him out the publishing business. 4 ore: 7 ; * You will want the greatest possible value for your dollars that into steel. You will want the right steel for each purpose. For example many manufacturers are now obtaining 25% more weight reduction without loss structural strength using Inland Hi-Steel. Others are adding 300% 500% longer life when exposed atmospheric corrosion using Inland Copper-Alloy which costs but little more per ton than ordinary steel. ror =? oom —— 30—THE IRON AGE, February 1939 Increasing numbers shops are using Inland Ledloy, the new lead-bearing steel—which permits 30% more than 100% increased machining speeds, you use sheets strip the right analysis combined with proper heat treatment, finish and uniformity will increase the speed your forming operations. Inland men will gladly check these economy possibilities with you. And their personal interest serving you may result some excellent methods lifting your product- appeal lowering your costs order peg profits higher during the RAILS TRACK BARS , i is 3 | > | South Dearborn Street, CHICAGO District Offices: DETROIT KANSAS CITY MILWAUKEE ST.LOUIS | 4 ACK the quiet little village hillside above the Monongahela River and the very heart the Don- | é Annealing furnaces Cold reduced finishing dept. Shears ing dept tion flow diagram oper- Heating Raw coil HOT ations the Irvin Works. BARS FRANCIS JURASCHEK Consulting Editor, The lron Age ° ° ora district, dream has come true. dream fantastic, wistful, compen- satory but hard, cold, practical dream, rooted the desire for- sheet, strip and tin plate the most efficient way. ° Pittsburgh’s golden triangle and hard the huge airport, more than years intensive planning and mil- lions dollars worth concrete and structural steel, electric motors and gargantuan machinery turned imagination into THE IRON AGE, February 7 Ru 2—Feeding slabs the pusher-rams the intake ends the heat- ing furnaces. The beginning the hot mill cycle. reality—the Irvin Works Big Steel. not particularly exciting these days read about the opening new industrial plant. often have rolling mills been built the past few years that announcements have become almost natural event toast with breakfast coffee. But not only new and big and filled with advanced technological ideas—these things have been said just truth- fully about other also happens the embodiment very common sense principle. ideal—straight-line flow. This news the steel industry. Not because the principle straight- line flow revolutionary contrary the basis all mass production effort), but because has always been difficult apply con- sistently the flat rolling steel. The strict application the principle 32—THE IRON AGE, February 1939 requires space; more space than seems have been economically available other mills. the application the principle has always been more less half-way measures—until Big engineers dreamed the Irvin Works, and spread out over mile and more sprawling hillside above Dravosburg. There’s story back this achieve- ment that merits thought; story the whole steel industry taking heart. For, basically, the fulfillment Big Steel’s dream the Irvin Works due, more than any other single factor, consistent and conscientious ap- plication every step the produc- tion problem, the art moving materials mechanically. any other one thing the whole project, the materials handling meth- ods and equipment brought into play Irvin tell the story more efficient production. Statistics are notoriously unimpres- sive these days. But two figures are worth bearing mind connection with the Irvin Works. Into its gates there will come from the Edgar Thomson plant Braddock, six miles the north, supply steel slabs 600,000 gross tons sheet and strip product every year. the entire capacity Irvin were utilized wide, gage steel, that ribbon would reach least times around the earth the equator each year. Thus, may appreciated that child’s play. The Production Flow The scheme production flow terms the general objectives are kept firmly mind. These all start with common denominator—slabs shipped from Edgar Thomson— production step; hot rolling. Then come three distinct split-ups. hot reduced strip sheet desired the end product, one line marches through the hot reduction finishing department directly shipping cooling IG. 3—Down tilter end 1270 section roller conveyor . | 7 | | | room. cold reduced strip sheets, tin mill products are desired, the line runs through continuous raw coil mills, where one through the cold reduction finishing department shipping room ad- jacent the hot reduced product shipping room, while the other line flows the opposite direction oc- cupy the tin mill space the southern end the Works. scheme shown very much simpli- fied detail Fig. From this diagram (not scale, roughly approximating the dif- ferent directions flow throughout the plant) clear that slab once received its way marches inevitably forward step step, with minimum lost motion. And this the first cardinal point efficient handling. The second point—a minimum handling operations sive process steps—requires more detailed examination these lines flow. For convenience description, the operations will considered four parts, roughly corresponding the four operations the Works; woling conveyor transfers coils trough- eyor 4 crane removing coils raw coil storage rooms from the trough section roller conveyor. first the common step hot rolling, then separately, hot reduced finishing, cold reduced finishing, and tin plate Hot Rolling the slabs are brought rail- road cars from the Edgar Thomson Works they are lifted overhead traveling crane and deposited neat piles according size and type the slab storage room. Thence, after flame scarfing, where handling done gantry crane, they are placed piles chain conveyor which runs across the intake ends three con- tinuous heating furnaces. Individual slabs are fed into the furnace from this conveyor transverse pushers, each slab pushing the slab ahead through the furnace and out onto the roll conveyor feeding the continu- ous hot strip rolling mills. From this point the hot mill cycle much like that any other mill breaker, four roughing stands, crop shear, another scale breaker, six finishing stands, flying shear, run-out tables, coilers and The hot mill can roll strip maximum width and the nominal rated ca- pacity this mill (which controls the entire capacity the Works) 600,000 gross tons per year. the end the hot mill line two coilers discharge short section transverse chain conveyor, the carrying plates which project but few inches above the floor level. This transverse conveyor discharges the up-ended coils right angles 1270 ft. long chain cooling con- veyor; new practice rolling mill procedure. Like the tion just mentioned, the carrying plates this conveyor run only few inches above the floor level, that coils may removed from the line any time without damaging the ends. This cooling convevor THE IRON AGE, February literally moving sidewalk, capable handling the entire production the hot mill coil form, and trans- ferring the two raw coil storage rooms while moving speed be- tween and ft. per min. Close the beginning this cooling line the conveyor passes through scale section where the coils are weighed. the coils are discharged onto the transverse line from the coilers, the strip checked for width and thick- ness. These data, with the weight, order numbers, heat numbers, etc., are chalked each coil; and these oper- ations, together with the banding Stack carrier han- dling bundles sheet metal be- tween various operations the cold reduction ment. 34—THE IRON AGE, February 1939 the coils the point discharge from the coilers, mark the only stage from slab raw coil storage room where necessary for human hands touch the steel. either side the cooling con- veyor are located the raw coil stor- age rooms, and appropriate points along the line, down-tilters ram- pushers are located discharge the coils their sides ends, quired, these storage rooms. each room overhead magnet cranes pick the coils and set them down desired the storage rooms. This finishes the first, and common step, IG. Ram truck taking coil from pickling tank discharge conveyor line the cold tion department. the production all products Irvin, Throughout each stage the prog- ress far, swift, time-saving mechan- ical handling has replaced human muscle. The flow-line has marched forward continuously, and re-handling eliminated. From this point on, various kinds and sizes product are manufactured, the ways inevitably become more complicated; but even so, great things have been accomplished the matter reduc- ing these complicated lines flow the simplest possible terms, involv- 4 4 | A dlit tg one q aro cor or spe she : mo’ set tret . Se 4 | dre and this whe | | | ing the least possible amount handling, the lowest possible cost. Brief outlines these procedures follow. Hot Finishing and Cold Reduction From the east raw coil storage room, coils are picked ram-type industrial trucks overhead cranes and transported various pieces hot reduction finishing equip- ment, the hot reduction department, or, desired, strip may handled here comes direct from the hot mill. this department are installed flying shears, resquaring shears, tem- per mills, recoiling and side-trimming lines, sheet pickler and scrubber. Wherever possible, the equipment has been laid out function con- tinuous straight-line flow. When this possible, conveyors connect one machine with another, make han- automatic. Where jumps from one piece equipment another come necessary, ram trucks handle coils, fork trucks stack carriers overhead cranes equipped with special sheet grabs handle piles sheet metal. Careful planning movements before the equipment was set place has resulted ex- tremely small amount actual han- work getting out the hun- dreds different sizes and shapes and weights product required from this department. The line flow marches inevitably onward toward shipping department, with back-tracking goods any- where. This shipping department located adjacent similar shipping department serving the cold reduced fnishing department, and both are equipped with adequate facilities for shipping out rail highway truck, with industrial trucks and overhead cranes all the handling work. Coils for cold reduction and for tin plate are picked the raw coil storage rooms magnet crane industrial trucks, and de- direct the uncoilers the ends two lines con- pickling tanks, one line capable handling strip in. widths, and the other in. widths. the far ends these pickling lines the recoiled strip runs out lines where ram trucks pick them for the cold reduction mills. going through the cold re- duction mills that the flow lines for finished products and for tin plate stock split. The first line goes through 3-stand tandem mill with capacity 200,000 tons strip per year, designed handle open hearth, Bessemer, Cor-Ten, Man-Ten, Sil- Ten and stainless steels widths from 4-high reversing mill may used here. The cold reduced material moved from the mills crane industrial truck either recoiler line which side-trims gage lighter material strip form, three flying shears equipped with roller levelers, side- trimmers, etc., followed drum-type squaring shears, oiling machines, fly- ing and resquaring shears, and com- bination open annealing and normal- izing furnace. All through the cold reduction fin- ishing department such degree care has been exercised laying out the sequence operations and spotting the equipment the most favorable locations, that handling has been reduced minimum. Wher- ever possible, conveyors connect one machine another, and otherwise, in- stack carriers and 7—Typical roller conveyor connection between temper mills and sheet finishing equipment. shears, where the strip cut into lengths ft. The coils sheets are cranes transfer cars and moved bulk the annealing furnaces. From these furnaces similar cars take the annealed metal the department proper, where there are located three 4-high temper mills, two for strip and one for sheet alone, and also 2-high temper mill arranged for either sheet strip. With these mills are located various pieces mis- cellaneous finishing equipment, such roller levelers, stretcher levelers, overhead cranes come into play. closely have operations been tied each other that even where han- dling equipment must used, its use has been reduced amazing degree. The Tin Mill Cold rolling for tin plate products done either 5-stand tandem high mill, the 4-high reversing mill; both which are located adja- cent the cold reduction mills for metal mentioned above. the cold mills, the coils, which for tin mill use are from in. in. wide, are ram THE IRON AGE, February = = ‘ 4 Fic. 9—Tractor moving transfer car loaded with black plate coils the annealing furnaces. truck three electrolytic cleaning lines. leaving these cleaning lines the coils are handled crane and transfer car the naces, thence transfer car the temper mills. From these coils are handled truck the shearing machines, where the strip cut into tin plate sizes. Sheared tin plate metal, stacked piles, then moved fork truck the batch white-picklers (except for such metal may here diverted the black plate warehouse). The sheets coming from the pickling tanks are stored batches, edge, bosh containers, where the metal kept under water until ready for the tinning operation. special type industrial lift truck used here pick the bosh tanks bodily with their loads water-covered sheets, and transport them the tinning pots. the tinning machines, which are specially designed straight-line units, the sheets are picked out the bosh tanks revolving permanent magnets and fed individually the tin plating tanks, from whence they are mechanically delivered bran-dryers and polishers. Here thev come out stacked neatly piles, all ready for inspection, assorting and packing. Nothing has yet been found take the place sharp-eyed, nimble- fingered girls for these final opera- tions. After the inspection ing, the finished tin plate packed base boxes, which are picked 8—Special type industrial trucks lift bosh tanks filled with water- covered sheets, carry them the tinning pots. 36—THE IRON AGE, February 1939 fork trucks and delivered the south shipping room, ready for counting, checking and shipping out rail motor truck. through the entire tin mill leaves the distinct impression that handling has been reduced minimum, straight-line flow principles have been worked out very logical manner, and that costs have been minimized quite much the application sound mechanical handling methods any technological advances pro- duction operations themselves. Summary For those who delight statistical information the following summary the principal materials handling equipment use the Irvin Works will interesting. There are overhead cranes, varying ca- pacity from tons, and span from 120 ft. Some miles standard gage railroad track have been will laid within the limits the plant site, large part this within the buildings proper. con- veyors, more than 1600 feet chain type conveyor use, and approxi- mately 5500 feet roller conveyor, exclusive run-out tables built integral part the production equip- ment. There are industrial trucks various types use, about evenly divided between storage battery and gasoline-electric drives. addition there are several gasoline-powered tractors, six stack carriers special design, dozen special crane-hoist sheet grabs, and eight magnets used with connection service. pro teri low but are stee Fab Stee lie Shearing, Blanking, Drawing, Spinning, Forming and Riveting drawing stainless steel, the design the part formed and the number pieces produced govern the selection ma- terials for dies. Some shops short runs use low-carbon alloy steel, case hardened, but most cases these applications are for rolling machine dies will not permit any great amount redressing, because doing the hardened surface case removed. Because the high tensile strength stainless steels, combined with their high alloy content and toughness, advisable use first class tool steels. For blanking and punching dies, also shear blades, steels chromium type steels with similar high alloy content are recommended. Some manufacturers use hardened die steels for small intricate dies where Fabrication Republic Enduro Stainless Steel,” shortly published Repub- lic Steel Corp. STAINLESS retention close tolerances fae tor. Draw rings and pressure pads alloyed cast iron hard alloyed bronze have proved greater value than ordinary cast analysis and best treatment alloyed cast iron is: Carbon, per cent; manganese, 0.75; silicon, 1.20 1.50; chromium, 0.75 1.00; and nickel, 2.50 3.00 per cent. This iroa heated 1550 deg. uniformly, oil quenched and drawn 900 deg. The resulting Brinell will found, however, that hard cast bronze rings will result much more satisfactory product, the elimination scoring. fact, bronze almost imperative where the product polished after draw- ing. Blanking and Shearing Stainless steels cannot sheared with the same clearance used ordi- nary sheet steels. The metal must cut through the entire will not snap break off will other materials. Hence, suggested that the shear blades maintained with very close adjustment and with keen edge conditions will permit. Dull shear blades used trimming row margin light gage metal will have tendency drag and turn over the edge the metal instead part- ing from the sheet. This condition also holds true slitting strip coil stock. the cutters are not regularly ground keen edge and maintained such, the dullness the edges will have tendency cause considerable camber and burr, unless sufficient ten- maintained between the pay-off and recoiling reel. The pay-off reel should ad- justable type permit the arms holders grip firmly the inside diam- eter the brake drum ar- ranged the reel adjust the proper tension and prevent free running the coil will assist greatly prevent- ing cobbles and damaged Unless otherwise noted the sheet, the inspection stamp will the prime side all cases. coil stock the prime side will the outside the coil. This information help those desiring use this side for polishing finishing. blanking punching, much closer clearance should maintained eliminate dragging the metal and causing burred edges. Definite fig- ures cannot given and will vary according the thickness the ma- terials. Some shops work clear- ance one-tenth the thickness the metal. For example, using in. gage material, desired punch hole in. (0.250 in.) diameter. Therefore the die diameter should 0.250 1/10 (0.010) 0.251 in., possibly much in. The re- verse this equally feasible. Use die 0.250 in. diameter and punch 0.248 0.249 in. diameter. Caution should exercised the THE IRON AGE, February 1939—37 ‘ = fis : 4 as ° ° > elimination removal the burr en- countered during blanking shear- ing. some cases the burr quite factor retarding the flow the metal between the draw ring and pres- sure hold-down pad. Burrs encountered stainless steels are hardened such degree that passing over the surface the die ring pressure pad, unless the dies are extremely high hardness, the surface will gouged scratched. Lubrication Before placing the blank the draw dies, lubricant high film strength and adhesion qualities should ap- plied. brush, swab spray gun should used apply the compound uniformly over the surface subject friction. Several special drawing lubricants are obtainable from various producers, with offices and warehouses throughout the coun- try. The most suitable have either oil animal fat base, highly sulphur- ized, which can diluted proper consistency for the particular opera- tion. the draw operation light and shallow depth, water soluble solution will suffice. draw heavy, oil soluble solutions similar prep- arations are preferred due their greater adhesion properties. Drawing drawing, should remem- bered that stainless steels require con- Enduro 18-8 analyzes 0.08 Si, max. Mn, 0.030 max. and 0.030 max. and 0.10 max. carbon. used where corrosion resistance more important than high strength toughness. 38—THE IRON AGE, February 1939 lubricant stainless prior the first tion. siderable more power and more rugged equipment than ordinary Enduro 18-8! with its exceptionally high elongation very excellent for deep drawing and difficult forming operations. Due its rapid work properties physical characteristics, however, requires greater force displace, approxi- mately double the energy used for ordinary steels. All steels higher alloy content are sluggish to. flow either hot cold forming. speed approximately one-half that applied regular draw work will result flow- ing the metal greater depth and will eliminate excessive breakage and scoring the dies. Pressure pads should adjusted exert greater force the blank prevent any wrinkling folding the metal flowing into the draw ring. wrinkling permitted occur, the draw ring may damaged the bot- tom the shell fractured. The clearance between the punch and draw die should about twice that used ordinary steel brass and the radius the draw ring should greater and the ring well polished, buffed possible. Oil stones and kerosene should used preference abrasive cloth similar materials removing adhesions metal adher- ing the draw ring pressure pad. Blanks all cases should suf- ficient diameter retain flange the shell. the drawn part pro- duced without this precaution, season cracking the sidewalls may result, particularly the reduction exces- sive, unless the parts are immediately washed remove the drawing com- pound and then annealed. the part produced requires second draw additional operations, advisable remove thoroughly the drawing com- pound and anneal the parts. The 18-8 grade stainless, with its higher ductility, can reduced ap- proximately per cent the blank diameter. Greater reductions are pos- sible, governed the speed which blank has been given one draw second ° ° RIGHT stainless steel blank has been being the metal flows through the draw ring and the consistency the lubricant applied. types stainless, such Enduro are lower ductility, the average reduc- tion being approximately per cent. The percentage reduction in- fluenced the thickness the ma- terials. The same precautions are observed fabricating the straight- on 4 id bas Wa lov all or 3 cer mo wit ‘ to chromium types outlined for the 18-8 analysis, although previously explained the ductility this analysis lower and therefore requires addi- tional annealing, which accom- plished lower temperature than that for the 18-8 type. Cleaning The cleaning drawn parts depends the type lubricant used. Oil and now being lubricated for the draw. shape and the edge now anged. base lubricants can best removed washing cutting with kerosene, fol- lowed caustic soda similar type industrial cleaner degreaser. all cases certain that the pigment solid matter from the lubricant has S-1 analyzes 12.5 per cent and 0.12 max. carbon, and has moderate corrosion resistance combined with high strength and toughness. 18-8 has higher nickel (11 Ni) than 18-8, and does not work harden fast 18-8. been thoroughly removed surface the metal. soap base lubricants are used, boiling water commercial cleaners will remove the adhering film the lubricant without resorting the use kerosene. very essential that the surface the parts thoroughly cleaned any trace grease dirt. Parts should then handled with clean gloves tongs, since any smudge spots, permitted remain the surface the parts annealed, will burned into the steel. Spinning and Forming Spinning has been thought many problem, but such fabrication large stainless steel coffee urn tops and sim- ilar products now being accom- plished without difficulty with the 18-8 grade. the spinning deep, one more anneals may necessary. Because its greater ductility, the 18-8 grade requires less annealing when spinning deformations are severe. Hence, this grades for spinning. Because its tendency harden when cold worked, the 18-8 grade requires considerable power spin and likely wrinkle along the edges. This can over- come flanging approximately one inch away from the edge the blank before working the center metal. The burr should removed and edges turned smooth before starting. Cast iron tools have been found quite successful spinning the 18-8 grade. nickel-chromium cast iron, heat treated maximum hardness, superior straight cast iron for this purpose. The analysis should ap- proximately follows: 3.00; Ni, 2.50 3.00; Cr, 0.75 1.00; and Si, Roller type tools are advantageous over the regular type, but compound tools are necessary heavier gages Soap the yellow naphtha typ: used for regular steel spinning has been found work equally well spinning stainless steels. Some oper- ators apply heavy polishing tallow conjunction with the soap. previously stated, the toughness and higher hardness stainless steels make them resistant flow. This ap- plies spinning the same deep drawing. Extra effort and heavier and more sturdy equipment are required working these types metals. essential retard the spindle speeds approximately one-half that used for regular steels. Trimming the edges can accom- plished with greater ease using rotary type cutter. case this type equipment not available and cut- ting tool must used, stellite similar analysis tool steel will prove very satisfactory. Retarded speed trimming very essential due the tendency the metal work-harden. edges are wired, use wire the same analysis the material from which the part spun. Should steel wire used suggested that solder seal used under the bead prevent precipitation iron oxide from the wire. The use the 18-8 grade for parts produced spinning has enabled the operator flow the metal with less resistance, with fewer an- neals and some cases without an- nealing. Since the spinning operation will destroy any surface finish, No. fin- ; completed spun part here shown removed from the form. ish material should for all spun parts. Furthermore, polished finish such No. finish will not re- tain the lubrication well No. finish, Note: not bead over the edges unless the surface oxide has been removed either pickling me- chanical cleaning with abrasive cloth wheel. Riveting rivet stock must tured with greatest care and thorough, inspected: “Only smooth, centerless ground cold drawn stock used. Any seams flaws are most objectionable, being liable and 0.25 max. carbon, and designed for oxidation resistance to 2100 deg. F. rather than strength toughness. Enduro 18-8 has higher silicon Si) than 18-8, improve tance. cent Cr, and 0.20 max. carbon. Has oxidation resistance 2100 deg. and physical properties above the latter analyzing 0.08 max. Cr, and Ni. and 0.20 max Has high strength and oxidation resistance high temperatures. 40—THE IRON AGE, February 1939 open upsettiag operations which necessitates rejection. inspection, suggested that all rivet stock, particularly sizes, given white pickle final opera- tion, structure with and impact strength. capable being bent cold 180 deg. around mandrel equal its own diameter without cracking the out- side the bent portion. upsetting also desirable. This provides that full sized specimen bar with- stand upsetting from length in. diameters in. diameter with- out cracking splitting when heated driving temperature. Rivets small sizes—up in. in, diameter—may be, and pref- erably are, manufactured and driven cold. Larger sizes must manufac- tured and driven hot. Annealing rivets after manufacture, whether for hot cold driving, not necessary. All rivets for hot driving should provided with cone heads, while rivets for cold driving should have the usual diameter and larger should have 1/16 in. radius fillet under the manufactured head. Rivet holes plates may drilled the latter, the hole should reamed remove strained distorted metal. holes plates in. thicker should chamfered countersunk insure rounded corners under rivet heads. All rivets must carefully heated the proper driving temperature determined the analysis. Rivets must heated muffle type fur- nace with pyrometers good working order. Rivets must held the furnace longer than min. for the straight- than min. for the chromium-nickel austenitic series. Rivets which have been overheated held too long should discarded. Hardenable Analyses and upset cold, using eters. Larger upSet and headed but time be: all such hardening, heat- ing high will tend produce and hardening and must Non-Hardenable Analyses Types and gain small may headed upset cold; larger rivets, hot. type AA, rivet heat- ing temperature not exceed 1400 1450 deg. For Type HC, 1500 deg. should the Straight-chromium alloys this type are very subject grain growth high temperatures and this strictly avoided, otherwise toughness and ductility will greatly reduced and rivets will unsafe. Austenitic Alloys etc. alloys this type driving elevated temperatures much more rapidly than plain steel, precau- tions against this occurrence must carefully observed proper otherwise rivets cannot upset driven. Small rivets, headed and upset cold. Larger rivets should driven hot, very hot, that the rivet will completely finished before has cooled sufficiently be- come hard. Rivet heating tempera- | tur deg | Ing the an Cal Sul a | bei be: ere | Q1\ sig pre =. the Ins the the 1Z€ tures for these alloys should 2100 deg. Protecting the Surface polishing stainless steel No. finish, No. Tampico finish, No, finish and No. mirror finish, ex- treme care exercised the mill obtain flawless surface—free from pits, and other defects. certain applications polished sheets, fabrication necessary. such cases, only careful handling required preserve the lustrous finish. Many applications polished sheets hospital and kitchen equip- ment, dairy equipment, meat packing equipment, soda fountains and many architectural uses—require brake press work followed welding soldering and necessary grinding and tial that precautions taken elim inate the possibility scratches, dents and other marks the polished sur- face. quite difficult match hand, formed object, the finish that was obtained polishing machines the the fabricator protect the polished surface before any work rather than faced with the job polishing out marks that may have appeared through equipment. While not maintained that possible entirely prevent scratch- ing and galling all types work, the tabricator will save trouble, time and money exercising every pre- caution against damage Protection Methods Several methods lubrication are being used. suggested that the fabricator select the method which best adapts itself his particular op- erations, The first consideration given the condition the dies. They should well polished and the first sign any pickup the metal, the press brake should stopped and the dies stoned satisfactory method for preserv- ing the polished finish the metal the application adhesive tape the dies. This method can used where the work applied the metal not brakes. Its use not recommended for deep drawing. The merit this type protection can easily real- ized, prevents direct contact be- tween the polished surface the En- duro sheet and the hardened steel the dies. this same line thought, the use thin paper between the polished metal and the die working well some cases. Wax paper, oiled paper, cellophane and some cases ordinary newspaper have been used with marked success the die scratches. The paper used adjunct the lubricant. Another method protecting the surface polished sheets both ship- ping and handling plant apply ordinary wallpaper wheat paste—allowing about hr. dry. Also adhesive paper and tape in. width are obtainable from several sources. soldering welding necessary after the sections have been formed into various shapes, the protective pa- per may removed with hot water the point which the parts are joined. Depending the application, the protective paper some cases re- moved before shipping the parts customer, other cases the surfaces are permitted remain covered, espe- cially building erection until give the final cleaning for approval and acceptance. The proper time for is, therefore, governed entirely the ap- plication. Protection During Building Construction The wide use polished stainless steel for exterior decorative purposes building construction has made necessary the means protecting from what may termed “building meaning plaster, con- crete, ashes, rust from steel work and other contaminations with which the polished sheet may come during the erection building. Several the large paint concerns have developed special lacquers which will protect the sheet for period one year longer from the effects The lacquer can removed the completion off from the effects the weather. The need passivation has not been stressed this Its neces- sity should thoroughly implanted fabricators’ minds. Whenever steel rolls, steel dies shears come con- tact with Enduro, there possibility discoloration due film iron being abraded its surface. This film should removed, either with the nitric acid passivation treatment steel buffing compounds. use paper applied the surface the stainless steel protection during welding and grinding shown here. THE IRON February ; ky 7 coe a FIG. HIS practically chromium-free iron contains considerable ferrite, and large flakes graphite. The per cent chemical composition is: 2.53 Si, 0.59 Mn, 0.14 0.12 and 0.04 Cr. 100). FIG. addition only 0.45 per cent chromium converts the ferrite the base iron pearlite. The size the graphite flakes reduced. 100). castings varying sections are obtained low-chromium cast iron content added the ladle. This iron essentially free from structures, the presence which would castings intended for applications re- wear. The ferrite such formations eliminated the chromium—which stabilizes cementite, increases oxidation resistance, other valuable functions. the same time, similar tendency toward for- mation the objectionable tic’ graphite prevented the late addition part the silicon—which also development normal flake graphite. The chromium added either the cupola means ferrochrome special foundry The silicon addition the ladle best made ferroalloy containing per cent more silicon. The evidence upon which these con- *Among others see: Oc- currence and Control,” Ban- croft and Dierker, trans. American Association, 1937, pp. 449- 466. “Late Silicon Additions Cast Iron,” Crosley and Herzig, The Foundry, Vol. 66, No. (Jan., pp. 28, and 73. 42—THE IRON AGE, February 1939 Fig. Beneficial Effects clusions about the effects chrom- ium are based was ob- tained adding the alloying ele- ments base iron produced commercial foundry. Analysis this base iron showed the following per cent composition: 3.42 total carbon, silicon, 0.59 manganese, 0.14 phosphorus, and 0.12 sulphur. Typical effects the microstruc- ture this cast iron obtained the presence low-chromium additions chromium practically free ferrite normally present the unalloyed base iron (Fig. and sto 0.77 per cent chromium (Fig. produces some further pearl- itic refinement, but appreciable amounts free cementite. This accordance with observations that, after establishment pearlitic structure minimum chromium addition, considerable tolerance for additional chromium exists before the appearance free cementite. 1.19 per cent chromium (Fig. present the base iron, some free cementite observable. The cement- ite frequently associated with and accents the phosphide eutectic areas. The amount cementite is, this case, still not sufficient interfere seriously with machining. romium and The physical properties cast iron with compositions similar those the first four illustrations shown Table Step-bars cast from this commer- cial base iron showed chill sections down in. with 0.45 per cent chromium content: and with 0.77 per cent chromium the iron was 5—A plain cast iron containing unde- graphite structures. Per cent composition: and 0.03 Ni. 250). » £ a Fig. ar e Sil gray section. With 1.19 per cent chromium content, section was gray and section predominantly gray. These results are important evidence that foundry employing base iron relatively common type can materially improve the physical properties and, course, the heat endurance this iron, simple ladle addition ferrochro- the structure this al- loyed cast iron still contains some graphite, chromium addition has converted the ferrite pearlite, and has thereby improved the wear-resist- once the cast iron. Per cent composition: and 0.23 Ni. 250). Probably one the most important effects chromium that improv- ing the wear resistance cast iron eliminating the deleterious effects the previously mentioned ic’ graphite-ferrite areas. These occur with great fre- quency even supposedly pearlitic cast iron, and particularly irons made with appreciable amounts steel. these areas, when present, are most plentiful near the surface the casting, they almost invariably act starting points for wear castings such lathe beds, cylinders, and piston rings. This phenomenon has been discussed extensively re- cent papers*. The tendency chrom- ium additions prevent ferrite for- mations such areas can very read- examination. Figs. and are micrographs square sections two irons used for casting lathe parts. The analyses the irons are shown Table Although both irons show areas fine “dendritic” “eutectic” graphite, the chromium addition iron No. has largely eliminated the ferrite that normally occurs conjunction with graphite iron such No. not treated with chromium. Since investigations have shown that eutectic graphite much less subject “pitting out” when embedded FIG. increase the per- centage chromium from 0.45 0.77, the pearlite still further refined. Free cementite still essentially absent. 100). FIG. 1.19 per cent chro- mium has been added the base metal, some cementite with phosphide) observable. The metal, however, icon Additions Cast the harder, more rigid pearlitic matrix (rather than ferrite), the wear resistance the iron defi- nitely increased. The various effects alloying ele- ments cast iron are, course, influenced the presence silicon, and, might added, the manner which the silicon added. though the effect varying the amount silicon contained the cupola charge well known, the marked change the character cast iron resulting from melting charge containing 0.5 1.5 per cent less than the desired content and adding the balance the silicon the ladle has not yet received the wide attention that merited. However, some information properties resulting from such pro- cedure has recently become available. The marked change microstruc- ture occurring when this method silicon addition used illustrated Figs. and 10. Fig. shows the structure 0.50 per cent chrom- ium iron that did not receive ladle addition silicon, while Fig. shows the structure iron that similar composition, but the silicon addi- tion which was made partly the ladle. The effect such addi- tions the physical properties also shown Table III. From the micrographs Figs. THE IRON AGE, February Fig. Fig. 7—This 0.5 per cent chromium cast iron has been made without the addi- tion any the silicon the ladle. The matrix mostly pearlitic, but the graphite structure could improved. 100). 8—This 0.5 per cent chromium cast iron has received part its silicon addition the ladle and has excel- lent structure assuring splendid physical properties. 100). and 10, clear confers considerable immunity wall addition silicon the ladle results the suppression localized “den- and produces even distribution normal flake graphite. ment mechanical properties results. sensitivity—that is, there less tend- ency for castings increase hard- ness places where Tests with step-bars confirmed this. example, the 0.5 per cent chrom- most striking but little recognized ium iron (No. 7), whose silicon was added the cupola, possesses hard- TABLE Effect Chromium Additions the Physical Properties Commercial Cast Transverse Properties (12-in. Span) Tensile Compressive Brinell Iron Chromium, Strength, Deflection, Strength, Strength, Hard- No. Per Cent Lb. In. Lb. Per Sq. In. Lb. Per Sq. In. ness 0.04 2100 0.273 27,000 94,300 163 2 0.45 2675 0.280 53,800 122,200 207 3 0.77 2550 0.278 35,600 117,100 207 1.19 2350 0.263 36,100 121,200 235 Analysis base iron, per cent: 3.42 total carbon, 2.55 silicon, 0.59 manganese, 0.14 phosphorus, and 0.12 sulphur. TABLE Composition Cast Used for Casting Lathe Parts Total Iron Carbon, Silicon, Chromium, Manganese, Nickel, No. Per Cent Per Cent Per Cent Per Cent Per Cent Per Cent Per Cent 5 3.22 1.95 0.03 0.62 0.4174 0.10 0.03 8 3.27 2.44 0.52 0.80 0.175 0.096 0.23 TABLE Effect Adding Part the Silicon Content Cast the Ladle Instead the Cupola Charge Transverse Properties Silicon Final Analysis, (12-in. Span) Tensile Ladle Per Cent Strength, Iron Addition, Strength, Lb. Per No. Per Cent Lb. Per Cent In. 7 None 3.01 3.51 2.41 0.54 0.03 0.10 3300 0.102 36,800 1.40 2.99 0.53 2.59 4200 0.150 45,500 9 None 3.08 1.03 2.59 ite sae pe 4250 0.120 44,100 10 1.40 2.95 1.10 2.59 ask ney Te 4325 0.125 46,700 44—THE IRON AGE, February 1939 1G. 9—The per cent chromium cast iron shown here did not receive any its silicon addition the ladle. 100). 1G. 10—This per cent chromium cast iron received part its silicon addi- tion the ladle. result has improved graphite structure. Despite traces martensite, machinable. 100). ness 430 Brinell sections, which nearly 200 points harder than sections. Contrast this with iron No. which similar com- position but has silicon. This has hardness only 250 Brinell sections, and has essentially. the same hardness sections. Likewise, the per cent chromium iron (No. 9), which was shows hardness 450 Brinell sections; whereas No. iron, which similar analysis and con- tains ladle-added silicon, has ness only 320 Brinell sections, and uniform throughout. similar effect has been noted with intermediate amounts silicon added the manner described. ec ol re ; ANNEALING COLD ROLLED STR stallation now use the strip manufacturer. This equipment, made the Electric Co., Salem, Ohio, consists electrical heating chamber, relatively long continuous cooling chamber, and spray cooling section adjacent the discharge end. Reeling and unreeling equipment provided the ends the furnace installation signed for continuous parallel strands strip wide, the equipment may used for single strip in. width, and any number narrower strips within the clearance dimensions in. operation, strip continuously passed from the unreeling apparatus through entrance vestibule the charging end the furnace chamber, where comes contact with and conveyed through the atmosphere filled heating and cooling chambers dividual rolls are spaced approx- imately 2-ft. centers. After tively short time the heating cham- ber, the continuous strips pass through water coil type cooling chamber which the temperature the mate- rial gradually and uniformly low ered throughout the section stock until such time passes into short spray chamber jacent the discharge end the cooling hood. The stock with water temperature approximately 190 deg., and thus quickly cooled temperature ap- proximately 200 deg. which ficiently low insure discolora- tion upon the passing the work into the outer air, but allows sufficient residual heat retained within the stock insure the strip being dry and bright emerges from the furnace equipment, shown the accom- panying photograph. Clean, scale-free work made pos- sible designing the furnace equip- ment substantially gas-tight and then purging air means the non-oxidizing products combustion formed gas cracker generator. motor drive and variable speed reduction are arranged quick- and easily provide the proper time and speed through the heating cham- ber for each type and thickness strip normalized. Although ordinarily used peratures approximately 1750 deg. the temperature within the fur- nace chamber may varied according the normalizing procedure most suitable the requirements the various types strip. Temperatures high 2000 deg. are possible. Temperature control the heating chamber accomplished means thermocouples three distinct zones, electrical heating elements each zone being power supply through relays and switching equipment according the control the respective pyrometers. The equipment shown rated 275 kw. and has been designed for the continuous bright production 2000 Ib. per hr. steel strip heated 1750 deg. THE IRON AGE, February : | | installation low heat city pits for cool- ing chilled cast iron car wheels. EGULATION the chill wearing surfaces and the elimi- nation all initial shrinkage strains are two important phases the production chilled wheels. The depth the chill and known quantity and its regulation not with present knowledge the subjec