The Iron Age 1939-08-31: Vol 144 Iss 9

FRITZ FRANK President J. UW. VAN DEVENTER Editor c. &. WRIGHT J. A. ROWAN A. 1. FINDLEY Managing Editor News Editor Editor Emeritus Machinery Editor Art Editor Metallurgical BRdiior Asseciate Editors Washington Editor Resident District Editors Pittsburgh Chicago Cleveland Detroit Correspondents London, England Cincinnati FRAZAR Boston Hamburg, Germany MEYER CHARLES Post Milwaukee San Francisco SANDERSON ASA JR. Toronto, Ontario Birmingham Leroy ALLISON toy EDMONDS Newark, N. J. St. Louis AUGUST 31, 1939 Buffalo Owned and Published Gear Blanks Cast CHILTON COMPANY (Incorporated) Nickel Plate—Why and How Editorial and Publication Office Executive Offices Inclusions Rimming Steel a. and 56th Sts., 239 West 39th St. What's New Cutters and Small OFFICERS AND DIRECTORS MUSSELMAN, President Throw Away the Scrap Barrel FRITZ FRANK, Executive Vice-President FREDERIC STEVENS, Vice-President GEORGE GRIFFITHS, Vice-President WILLIAM A. BARBER, Treasurer JOHN BLAIR MOFFETT, Secretary JOHN VAN DEVENTER, JULIAN CHASE, THE NEWS BRIEF THOMAS KANE, CHARLES BAUR, CARROLL BUZBY, Weekly Ingot Operating Rate BAUR, General Advertising Manager Plant Expansion and Equipment DIX, Manager Reader Member, Audit Bureau Circulations Member Associated Business Papers Indexed in the Industrial Arts Index. Published every Thursday. Subscrip- sessions, exico, Cuba, $6.00; Can- ada, $8.50; Foreign, $12.00 New Industrial Literature Single copy, cents. Cable Address, ADVERTISING STAFF Emerson Findley, 621 Union Bldg., Cleveland H. K. Hottenstein, 1012 Otis Bldg., Chicago *eirce Lewis, ood war: ve., etroit H D. C. Warren, P. 0. Box 81, Hartford, Conn. 1595 Paeifle Avenue, Long Copyright 1939 by Chilton Company (Inc.) | f ; ‘ Bin | } ae | Ryerson Certified Steels also include carbon, tool and stain- less steels. Partial list prod- ucts shown below. Write for the Ryerson Stock List, which gives all Ryerson Certified Steels. Beams, Structurals Channels, Angles, Tees, Zees Hot Rolled Bars Bands and Hoops Floor Plate Plates (over kinds) Sheets (over kinds) Alloy and Tool Steels Heat Treated Alloy Bars Stainless Steel Cold Finished Shafting Strip Steel, Flat Wire Mechanical Tubing Boiler Tubes and Fittings Welding Rod Rivets, Bolts, Nuts, Washers Concrete Reinforcing Babbitt Metal and Solder John Company and Rockwell Streets can have this Valuable Guide Treatment Shipped with Thousands steel buyers are now enjoying the time money saving features the Ryerson Certified Alloy Steel Plan. They get carefully selected alloys which have all ening factors (analysis, grain size, etc.) within very range. With every shipment, large small, Ryerson accurate data heat treatment response, and chemical and physical properties. There need test, experiment order secure desired results. You too can have this valuable data. given additional cost obligation. Simply specify Ryerson Certified Alloy Steels your next requisition. Immediate will made from large and complete stocks these rately identified, known quality steels. Joseph Ryerson Son, Inc., Chicago, Milwaukee, Philadelphia, St. Louis Cincinnati, Detroit, Cleveland, Boston, Buffalo, Jersey ) Yj" Yj Yt Yj g eets his and Steel sends ment hout ified nent ... RON AUGUST 31, 1939 Vol. 144, No. Quarter! some time American business has had suspicion that not over-popular with the New Deal Administration. (Please note that this term excludes the Democrats, many whom are business men themselves and have make profit meet payroll.) Indeed, many business men who have listened appeals for cooperation and have repeatedly grabbed the administrative olive branch, only find turn into poison ivy, may have wondered whether there was something about themselves that even their best friends hesitated mention that would cause such nose lifting and turning away after each get-together. may reassuring great many business men and in- dustrialists who have had this experience learn that the trouble not halitosis but something far removed from business and business men, fact something that has never had anything with business. The trouble, generically speaking, the the President playfully calls his closest adviser and most powerful com- poser New Deal strategy and policy, Thomas Corcoran. Tommy the Cork, you know, the head chef the unofficial yet apparently kitchen cabinet. and his fellow amateur but ambitious cooks—there are quite number them—comprise the brain trust, rather what remains after much the brains have resigned. this group that mixes the purges for unruly Congressmen and that stirs the nauseous messes that business asked swallow for its Moley, original brain truster, tells the inside story revealing series now running the Saturday Evening Post. Most amazing all the attitude present chief brain truster Corcoran toward business revealed remark made him Dr. Moley. effect, reported Dr. Moley, this you are fight- ing with business man ‘Polack,’ you can give Why the chief New Deal adviser should add the Poles the list those who should receive quarter, hard say, especially since there are several million good American voters Polish birth descent who will remember this remark next election day. for the business men, very few indeed are optimistic enough hope for any quarter from Tommy the Cork thin dime from the whole New Deal. pant A\y | fe? { | | aN A : ty > Equipped with every useful device science has devel- oped, Inland’s two continu- ous hot strip and sheet mills maintain the highest preci- sion standards. SHEETS PLATE BARS Here, Inland, find the last word continuous mills—the new 44” Mill which, to- gether with the Mill, assures ample capacity with effective quality control. Many steel users are effecting new production economies with Inland Hot Rolled Sheets because their dependable, uniform gage and excellent forming qualities. invisible feature this better product the care exercised Inland metallurgists ing sheets exactly suited your own needs. For full information about Inland Hot Rolled Sheets, call your nearest Inland office. PLATES STRUCTURALS TRACK ACCESSORIES REINFORCING BARS j 3 | ANY scientist trying solve one problem has been amazed run into discovery far more significant than the intention the original research. metallurgists the United States Steel Corp. had not noted the importance definite time periods heat treating years ago, while they were trying solve break- age problems regard tempered they might still unaware method imparting improved ductility and hardness steel. was back 1928 when brittleness due transverse cracks was the sub- intensive laboratory experi- ments which later led the discovery the theory now employed aus- tempering. Ten busy and troublesome years passed before the process first became available commercial basis. Today being applied Davenport and Bain. “Trans- Austenite Constant Subcritical Transactions American Mining Metallurgical Engineers, Vol. 90, 30, pp. 117 ates Patent No. 1,924,099. Aug. 29, 1933. DON JAMES Cleveland Editor, The Age wide variety finished parts within certain hardness ranges the Worces- ter, Mass., plant the American Steel Wire Co., where the first furnace started production February, 1938. Legge are the metallurgists whose names have been most promi- nently connected with this develop- Bain and Davenport first pub- lished technical paper’, 1930, their findings establishing the theory austempering. They were granted patent August, Legge as- sumed the task applying the process commercially Worcester, task ac- companied numerous problems be- fore success was attained. Austempering avoids the stage hard martensite heat treating. the process heating steel above the critical point austenitic structure, then rapidly transferring the steel hot liquid quenching bath held selected, constant tempera- ture below the critical range (usually from 350 deg. 750 deg. F.) for predetermined length time until transformation structure has been completed. Then the steel cooled room temperature any convenient means, usually water quenching. Hard martensite avoided and the resultant microstructure known “bainite.” Fig. shows the transition bainite. comparison, under the customary quench and temper process, the steel after being rendered austenitic heat- ing above the critical quenched water oil, resulting hard mar- tensitic structure, and followed reheating obtain the desired proper- ties before cooling room tempera- ture. Microscopic examination bainite shows grain structure with greater degree accicularity than tempered THE IRON AGE, August 4 be — : ° ° city { uc- martensite, and the needles are finer. experienced metallurgist can dis- cern the difference—for instance com- pare views Fig. with that Fig. Table interesting compari- son properties attained the two heat treating methods, applied 0.180-in. diameter steel rods. ap- proximately the same austempered product shows all-round improvement, including notable duc- tility. commercial practice Worces- ter, Mass., salt quenching bath em- ployed. This salt bath held some constant temperature, ranging from 350 750 deg. F., depending upon the composition the steel and the hardness sought. using fine- grain steel, temperatures 1550 deg. 1600 deg. F., which are consider- ably above the critical, may em- ployed dissolve all carbides without danger coarsening the structure. The definite predetermined period the constant sub-critical temperature highly important. The transforma- tion must complete itself without the intermediate stage hard martensite. seeking apply the process com- mercially, invaluable time and temperature curves have been de- veloped painstakingly through exten- sive trials order facilitate the selection the proper salt bath time and temperature. Thorough knowledge the steel’s transformation characteristics con- stant temperature required. The “nose time,” such shown Fig. par- tial S-curve), must well understood. For instance, whereas carbon steel the diagram, cooled rate No. passes the nose temperature without transforming and would proceed bainite structure, the three other rates for the same steel fail clear the nose 22—THE IRON AGE, August 1939 time, and the resultant product would not bainite but fine pearlite. Table shows hardness ceilings and suggested sizes for various carbon and alloy steels. The better properties aus- tempering are most pronounced be- steel containing 0.55 per cent can treated, recommended that the carbon content 0.60 per cent above. Metallurgists the American Steel Wire Co. also point out the existence maximum austemperable size for each steel composition, since sections must cooled ficient rapidity prevent transforma- tion relatively soft pearlite during the quench the austempering bath temperature. There are scores practical ap- plications including safety toe caps, Belleville springs, firearm parts, link chains, automotive fastening devices, parts for business machinery, textile machinery, small tools, door checks, fishing rods, and electrical Automotive needle bearings show improved bend and impact results after regularly specified with 10- 15- deg. bend. Austempered open-hearth steel, with hardness the required range, can bent 120 deg. with- Slow Beginning Beginning Finer and harder the Martensite 7/ME (LOGARITHMIC SCALE) 3—The effects composition and cooling rates structures are shown these partial S-curves for two different steels. Total trans- formation times are not shown. Ww v Mediurn Nose time Tac ring bath ap- link fter 15- ired ith- out fracture, and will withstand around per cent more the impact test than the quenched and tempered elec- tric Swedish steel. Shovels and forks, normally made are required withstand considerable bend and wear resistance. Austempered will exhibit more toughness and greater They naturally offer greater wear resistance the increased hard- Lockwashers, which are essentially springs, need high elastic limit and must not exhibit brittleness. They are tested twisting right angles. Under the ordinary quench and temper SAE 1055 steel for sizes stock equivalent square. With and and attain much higher elastic limit, still retaining the tough- ness required. Applied small screw drivers, straight carbon steel heat treated the conventional quench and temper bend about deg. before breaking. Austempering results the same steel, the screw drivers bend deg. and not fracture. Manufacturers which are pieces spring steel spe- cially shaped and placed the arch the shoe give strength and help maintain its shape, are interested uniformity, particularly from the distortion point view. Austempered shoe shanks, has been found, give greater uniformity, four five points higher hardness, and the ability still take set without breaking after the shoe shank has passed its elastic limit. also interesting note that whereas manufacturers are accustomed expect three four points varia- RIGHT 2—The tempered marten- site, shown here 1500 diam- eters, may compared with the 100 per cent bainite shown Fig. For bainite, the grain structure more accicular and the needles are finer. BELOW Re, the fencing foil the center these three was bent small circle without fracture. The circle may seen the top the middle foil. LEFT steel containing 0.80 0.64 Mn, and 0.166 per cent Si. Reading left right: Trace transfor- mation, per cent transformed, per cent, per cent and 100 per cent transformed. Photo- Steel Corp. research labor- atory. Samples etched with per cent picric acid; original magnification in. field) 1500 diameters. tion hardness under the customary quench and temper method, variation austempered parts has been reduced one two points. Austempering well adapted pocket knives, and results improved bend properties for pocket-knife blades, which are usually treated below hard- ness (which the “ceiling” the method). The back spring, vent breakage, can brought for greater elasticity with- out danger brittleness. wrench chains uses them carbon- molybdenum steel pins, which must chain incorporating pins heat treated conventionally was found break total load 22,000 Ib. When the pins were austempered R., the same upsetting became possible with- out fracture, and the chain broke 28,000 Ib. total load. highly interesting application austempering the fencing foils shown the first page this article and the foil the center the three, Fig. was bent small circle without THE IRON AGE, August | i | Distributing Conveyor hardening controlled conveyor atmosphere furnace Degreasing Water Washer Finished machine rinse tank machine leaves table barrels principal pieces equipment employed austempering production basis are shown this flow diagram, fracture. The circle may seen side manufacturers. The firms send made, other en- the top the foil. The other photo- their unheat-treated parts, and the the bath high graph illustrates the capacity the price per pound established the factor; heating the bath properly and foil flex and still come back its basis the quantity and nature the securing quick temperature changes original position. Fencing foils se- article. Outside companies having suf- order supply different cured austempering are sufficiently ficient tonnage install their own for various batches. hard and elastic withstand unusual equipment, warrant conversion flexing without taking set, although, their present equipment, will shown the photos, the capacity licensed they desire. ter. Principal equipment consists take illustrated the Striving apply the process com- degreaser, per hr. hardening circle before fracture still retained. brought many problems. hot salt bath, Austempering thus offers increased First determined was whether washer and hot blast dryer. safety for fencers, present foils wire should austempered continu- have been known fracture ata much whether finished parts should lower hardness, resulting injuries. done batches. Since very long Backlog the Worcester furnace, furnace would required for treat- which located the spring works ing wire continuously, and due tem- Study Fig. gives excellent idea the general layout the South plant, miscellaneous perature problems such long fur- textile supply parts, such the best initial approach was Property Tests 0.180 rings and miscellaneous springs. The operation. Furthermore, hard- other products going through the fur- nesses over would disastrous nace are, for the most part, austem- coiling and forming tools used Average Three Determinations. pered price per pound for out- fabricate the parts. With this decision Analysis Steel: 0.78; 0.58; 0.146; 0.042; 0.040 Treatment: Quench and temper—Pb bath 1450 deg. for min., followed oil quench; then tempered 650 for min. Austempered—Pb bath 1450 deg. for min.; transformed Pb-Bi bath 600 deg. for min. Grain Size 1450 deg. F.: 5-6, with dominating. Aus- Quench Properties tempering and Temper Rockwell 50.1 49.8 Brinell 489 486 strength, per sq. in. 259,300 259,000 BRASION tests Rupture stress, bicycle type per sq. in. 355,500 312,150 roller chains, show- Elongation, ing per cent loss per cent in. 5.0 3.75 weight. Each plot- Reduction area, ted point represents per cent 46.4 different chain Impact, 36.6 14.0 and Bending (free than Ruptured hr.) bend 150 without deg. length) rupture Per cent loss weight the above, Rockwell hardness taken flat surface; ultimate tensile strength computed orginal rupture stress computed reduced section; reduction area fracture; impact foot pounds with ft.-lb. hammer unnotched round specimen. Time, hours 24—THE IRON AGE, August 1939 By 4 aks RIGHT cester furnace showing instrument control panel left. Degreaser right with tote box beneath it. The work enters the furnace the left the operator the platform. Fig. salt bath tem- pering furnace which receives the work from the hardening furnace, looking toward the exit end. Work drops off salt bath con- veyor into the T-slot section foreground without leaving the salt bath. Fig. 8—(Bot- tom)—Another view production equip- ment. Degreaser, storage tank and trichlore- thylene tank are shown left. Hardening furnace and salt bath are across the rear. Washer, dryer and inspection table, right foreground. ° ° ° The work loaded the floor level into baskets which are then automati- cally carried sprocket chain and dipped into the liquid trichlore- thylene compartment the degreaser, followed the vapor phase. The basket rises and ejected gravity conveyor where the work distributed belt coveyor feeding the work into the gas-fired radiant tube hardening furnace, which has ef- fective heating length ft. There TABLE Showing Few Carbon and Alloy Steels With Austempered Hardness Ceilings and Suggested Maximum Austemperable Sizes for Each Type Steel. Maximum Diameter Hardness Round (or Composition, Ceiling, equivalent Per Cent square), In. 0.95 1.05 57-60 0.148 0.30 0.50 0.95 1.05 57-60 0.187 0.60 0.70 53-56 0.187 0.60 0.90 0.60 0.70 53-56 0.281 0.90 1.20 0.60 0.70 53-56 0.625 1.60 2.00 Alloy 0.65 0.75 0.75 0.95 0.25 Alloy (SAE 4150) 0.45 0.55 0.60 0.90 0.80 1.10 0.15 0.25 Alloy (SAE 4365) 0.60 0.70 1.0 0.50 0.80 larger 0.50 0.80 2.00 0.30 0.40 and lent ces- SAFETY TOE CAPS QUENCHED AND TEMPERED AFTER 5400 Ibs. COMPRESSION LOAD ROCKWELL POCKET QUENCHED AND TEMPERED BEFORE TEST AUSTEMPERED AFTER 7000 Ibs. COMPRESSION LOAD ROCKWELL KNIFE BLADES AUSTEMPERED } BEND TEST ROCKWELL BILLET CHIPPING CHISEL ROCKWELL HARDNESS SPLIT CHISEL There are innumerable objects now being austempered commercially. Above are three samples this type work. Note particularly the hardness uniformity the chisel, and the hardness and high compressive strength the safety toe cap. are four temperature control zones. The work fed automatically and carried through and heated austenitic temperature around 1575 deg. alloy belt. The time this cycle may varied from min., depending upon the size and composition the work heated. loading end. 26—THE IRON AGE, August 1939 From the heating furnace, the work dumped into the salt bath through chute into the bath, making perfect seal, and the steel conveyor the salt bath, which held the desired austempering temperature. The work lightly distributed the belt. the end the salt bath (but still within it), the parts drop off the conveyor into suit- able baskets, and when the time quired for complete transformation has elapsed, the baskets are mechanically lifted and dropped into water ing tank. The work then washed, dried hot blast, and followed the inspection, hardness testing, and finally oiling, tumbling ball blasting, the specifications require. The sand-sealed hardening furnace employs prepared atmosphere from 4000 cu. ft. per hr. unit. general, work ranging from small pieces 3/32 in. diameter and in. long, large parts in. diameter 0.1 in. thick with formation not higher than in. can handled. The four tempera- ture controlled zones (at entrance, center the furnace, discharge end and salt bath chute) are all Seventy thousand pounds sodium nitrite and potassium nitrate equal parts form the mixture the con- tinuous salt bath tempering furnace, which ft. long, ft. wide, and ft. deep. Fig. shows the bath from the discharge end. There are radiant tube burners, each side, and six temperature control zones, Fig. shows another view the en- tire installation. Temperature and time immersion being utmost importance the bath, close control necessary over both. Conveyor time usually runs from min. operated variable speed control, but additional time the bath can permited desired, because the work drops from the conveyor into the baskets without leaving Temperature control assisted the end nearest the hardening furnace auxiliary cooling tubes. The major portion the salt salvaged pumping salty water back top the salt bath through re- claiming cone. The salt bath unit removable for repairs, necessary. Extensive safety precautions have been taken against possible hazards operation the furnace, which has been made nearly automatic sible. Alloy steel used for the chute from the hardening furnace into the continuous salt bath. This because temperatures below 1300 deg. ordinary steel would tend catalyze the breakdown carbon monoxide elemental carbon, which might result ignition the bath surface. mine alarm has been rigged detect ex- cess carbon monoxide from either the prepared atmosphere outlet from possible faulty connections. analygraph records the the furnace atmosphere and in- dicates the need for adjustment, necessary. r BEND TEST ROCKWELL ROCKWE . git Ford Motor experi- mental work casting gear blanks centrifugal dies, first announced just year ago, said wholly successful and centrifugally- cast gears now are regular produc- tion. McCarroll, Ford metallurgist under whose supervision the develop- ment was conducted, said production all Ford truck ring gear blanks now was the centrifugal method. will extended full production the car ring gear and the transmission cluster gear quickly the necessary equipment completed. Greater strength, lighter weight, and faster production are the principal ad- vantages the gears claimed for the new method, McCarroll said. using sand cores the die, undercuts can made which would impos- sible conventional forging, out, and this saves weight and metal. Still more important, however, the greater strength these gears made centrifugal casting. Etched sections show the reason. some forgings lines metal flow are parallel lines greatest stress. Be- cause absence all flow lines the centrifugal castings, this condition does not exist. The metal equally strong all directions. The simplicity the centrifugal method especially noteworthy, shown the accompanying illustra- tion. The dies, which are made special low-carbon steel, are mounted turntable designed and built Ford engineers. There are them the turntable. Each begins spin approaches the pouring ladle, continues whirl for the two minutes required for the metal solidify, and then stops turning time for the operator remove the hot blank and prepare the die for the next casting. ingenious feature the casting turntable centrifugal force used lock the dies position. This done which are pivoted the middle. There weight one end, and hook the other. When the die spins, the weight flies out and drives the hook onto ledge the top half the die, securely lock- ing into place. When the die ceases spin, the weight falls down, auto- matically releasing the die for the re- moval the gear blank. now set one man loads the cores into the dies and sets position top half die, another pours the molten steel, and third removes the die top and gear blank. Approximately min. the time for one complete revolution the turntable. The dies are spun 190 r.p.m. the case the truck ring gear. For the smaller car ring gear blank, the speed 325 and for the transmission cluster gear with its still smaller perimeter, the speed 400 r.p.m. THE IRON AGE, August 1939—27 shed ting, GEAR BLANKS CAST CENTRIFUGALLY eral, 3/32 arge hick ath the on. the X- ERIPHERAL gas major im. operation. Herein are Extreme position tained previously three Platform used taking side Dust catcher Ore bridge mantie, Large bell VAP arrangement, elevation and section, and furnace lines the new Inland Steel Co. No. stack. The furnace has tuyeres. 28—THE IRON AGE, August 1939 7 J WY RY H ‘ \ RX <q ' Bureau Mines established the importance gas-solid contact the blast furnace column. Kinney, Joseph, and others made studies the distribution gas along radius various planes and from these surveys concluded that there was room for improvement the gas flow the furnaces investigated. result their studies has been better understanding those factors de- sign and furnace operation which con- trol the radial distribution the gases resulting higher furnace efficiencies. Irregularities occur blast furnace operation which are impossible ex- plain the basis radial distribu- tion the gas. has been belived that sometimes the gas flow may not the same along all radii plane, that investigations made the “Temperature Reading Blast Furnace Stock Column,” Hjalmar Johnson, Blast Furnace and Steel Plant, February, 1938. Furnace and Steel Plant, March, 1938. Peripheral Distribution Gases the Blast Furnace,” Hjalmar Johnson, American Iron and Steel Institute, 1938. HJALMAR JOHNSON Superintendent Blast Furnaces, Inland Steel Co. there may more gas flow one side the furnace than the opposite side, and such irregularity results ir- regular furnace Studies the gas flow around the periphery the in-wall three blast furnaces the Inland Steel Co. have been progress for five years. These studies have proved that the peripheral distri- bution gas major importance furnace operation. The purpose this discussion show that the same conclusion regarding the im- portance uniformity gas distri- bution the periphery holds fourth furnace, the Inland Steel Co. Madeline No. stack. Inland Steel Co. Madeline No. GAS FLOW was designed and built the Arthur McKee Co., which designed and built the first blast furnace that plant over years ago. com- plete new furnace—25 ft. hearth, 101 ft. high and rated 1000 tons iron per day. The principal dimen- sions and the general arrangement the furnace are shown Fig. de- tailed description the installation has previously been Fig. shown the platform elevation 110.281 ft. which used making studies the gas distribution. The furnace was blown Jan. 1939, and has been continuous operation. Certain conclusions have been stated regarding peripheral dis- tribution gases.* The temperature the gas four equidistant points plane about ft. below the stock line taken measure the peripheral distribution the gas. the tempera- tures the four points are the same, then the distribution the gas over the periphery four directions the Daily Blast Gross per Gross 1939 Tons Pig Iron Deg. Feb. 1009 1500 1230 986 1504 1150 929 1628 1245 974 1540 1120 Average 975 1543 1186 1009 1557 1280 915 1713 1220 905 1692 1270 720 2095 1185 Average 887 1764 1239 904 1676 1125 937 1640 1130 932 1623 1110 Average 941 1618 1124 Apr. 1013 1593 969 1684 1060 1006 1654 1150 1519 1330 Average 1035 1612 1168 TABLE Operating Data for No. Furnace Top Cu. Ft. Tem- Wind per perature Analysis Minute Deg. 54,000 285 1.07 0.027 54,000 285 1.15 0.026 54,000 300 0.98 0.027 54,500 300 0.026 54,125 293 0.027 55,000 310 0.91 0.032 53,000 295 1.00 0.033 55,000 420 1.03 0.034 53,000 425 1.19 0.032 54,000 363 1.03 0.033 54,000 330 1.13 0.028 54,000 350 1.12 0.030 54,000 330 1.07 0.032 54,000 330 1.19 0.030 54,000 335 1.13 0.030 58,000 345 1.04 0.025 58,000 355 1.15 0.025 58,000 335 1.02 0.027 58,000 320 0.80 0.030 58,000 339 1.00 0.027 Pounds Slag Dry Analysis Time Flue Lost Dust 38.26 11.74 62.2 38.44 12.09 56.8 38.60 11.54 60.4 38.94 10.95 34.5 38.56 11.58 53.5 38.98 10.82 62.2 39.86 10.99 49.0 37.80 11.26 148.0 37.94 13.36 295.6 38.65 138.7 39.04 11.49 86.7 39.10 11.92 55.0 39.20 12.11 38.62 11.37 56.6 38.99 11.72 64.6 37.36 14.28 11.0 37.02 14.75 18.5 38.06 14.34 17.8 38.14 14.17 39.0 37.65 14.39 21.6 THE IRON AGE, August J ution di hich three J 4 Thermocouple legend same. And the gas flow the pe- difference temperature the four points recorded inwall tem- perature chart, reflects condition within the furnace. When there little irregularity the furnace moves smoothly, the dust production satis- factory and iron generally uniform quality. Frequently there much ir- regularity, excess gas flow one side and deficiency flow 30—THE IRON AGE, August 1939 February 1939 February 1939 Tapping ° ° LEFT 2—Types records made inwall temperatures, Graphs show satisfactory furnace operation; those unsatisfactory oper- ation. ° ° RIGHT Relation- distribu- tion gases furnace operation. ° ° ° Thermocouple location the opposite side. Such non-uniformity the peripheral distribution the gases always results inferior fur- nace operation. Generally results much “blowing through,” frequently hanging and slipping. The move- ment stock irregular, iron varies quality, coke consumption and flue dust production increase. The inwall temperature record for four 4-day periods has been reproduced Fig. and furnace performance for these periods shown Table The type curve marked “A” ac- companied with satisfactory furnace operation, Even though water was charged any the stock the top temperatures measured the dust catcher averaged 293 deg. That the furnace was operating efficiently shown the average daily tonnage 975 with only 54,125 cu. ft. per min. wind (average). The burden sisted per cent sinter, per ship cet 1800 April 1939 cent Lake Superior ores. scrap scale was charged. Curves show period unsatis- factory operation, particularly Feb. and 18. The decided irregu- larity apparent Feb. was not damaging, but the gradual upward movement No. 8:00 a.m. Feb. was damaging. The temperature this point remained high throughout the period, showing excessive gas flow this side the furnace. large pro- portion the gas was not traveling through the stock, doing the re- quired work preheating and reduc- ing, but was short circuiting from the bosh zone this side and out. This resulted loss efficiency indicated the higher top temperatures which averaged 420 deg. and 450 deg. for these two days. The excessive gas velocity through this zone resulted much hanging and slipping and pro- duction only 720 tons Feb. 18. Average 1080 Daily production ,gross tons rm a L v Average 967 Average The decided excess one side Feb. and 18, shown the high temperature No. Thermocouple point, indicated improper peripheral gas distribution which always results inferior furnace operation. This has also been observed the Inland Steel Co. No. and furnaces. Frequent- has been possible correct such maldistribution checking the fur- nace severely; other times such treatment seems less effective. The operation improved after Feb. but was not satisfactory was the first period. The inwall tempera- ture record for Feb. shown curve (Fig. 2), and glance in- dicates the points are not regular while No. point frequently goes up, does not remain did Feb. 18. had remained up, and the excess gas flow past that zone had become established, the same inferior oper: ation would have resulted. ry- The curves (Fig. reproduce the type inwall temperature record that most satisfactory observe. The furnace moves along smoothly, and the operator feels confident there building within the furnace, and gouging the lining taking place. The smooth operation re- flected the average daily output 1035 tons 58,000 cu. ft. per min. wind. This was typical operation during the month when, this same wind, the furnace averaged 1000 tons per day less than 1700 Ib. coke per ton iron. The iron was uniform quality during the month, and casts were produced that were over 0.035 per cent sulphur. changes were made the oper- ation the furnace, which the management was aware, which would have caused the poor inwall tempera- ture record shown the curves Fig. materials used were the same, the wind blown was constant and filling mark was constant. The method filling was: Ore, ore, stone coke, coke, dump big bell. The coke was, always, charged volume, each skip weighing about 48,000 making total unit 9600 Ib. One the methods used place numerical value the peripheral gas distribution was measure, with planimeter, the area between the maxi- mum and minimum temperatures for each 24-hr. period. the peripheral distribution good the area distribution bad, the area gener- ally high. The daily production and the area the inwall temperature curves are shown Fig. Because there delay about one day the effect gas flow furnace tonnage, the averages for the production are one day later than the average for area. There decided increase area from Feb. 18. This in- crease area measured uneven peripheral distribution gas and this turn resulted irregular move- ment stock. Fig. are also plotted the number slips the fur- nace which the gas pressure ex- ceeded in. H,O measured the dust catcher. The irregular movement resulted decrease output from 967 830 tons for the four days, Feb. 19. When the gas flow was again uniform around the periphery, was uniform every in- dividual annular ring the plane, that is, the gases were more uniformly dis- tributed over the entire area. Conse- quently, the average gas velocity was its lowest, the movement the stock again became regular, and fur- nace operation was satisfactory. THE IRON AGE, August res, how ace = ist ROM its inception, electroplating been looked upon primarily decorative process. Later its history, electrotyping appeared outstanding exception this rule. And, more recently with the advent chro- mium plating, came the plate known “industrial” “hard chrome,” which has since made important engineer- ing place for itself, for coating tools, gages, dies, textile printing rollers, mainly for resistance wear but also some cases for resistance corrosive chemicals. Similarly, nickel plate has generally been considered decorative coat, the primary function being improve- ment appear- ance. coat- ing for ferrous metals has also served prevent rust, but this connection suf- fered general that electrodepos- its are porous. must admitted that this opinion was, the whole, justified, partly because imperfect plating practice, but main- because the coatings put were light and thin, generally, that porosity was inevitable. Within recent years, however, new aspect nickel plating has made itself apparent the more progressive and better informed elements the electroplating industry. The under- standing spreading among the users plating, the manufacturers elec- troplated products, that deposit nickel can highly protective coat- ing, effective wear and corrosion resistor, provided correctly ap- plied. The first realization this fact came from the discovery that chro- mium plate the thicknesses used for decorative purposes was altogether in- adequate rust preventive. de- posit 0.00002 in. ample provide brilliant, and (to the eye) continu- ous, non-tarnishing coat with the blu- ish tinge which has become popular with the public. Under the microscope, however, was apparent that such thin coat does not fully cover the base metal but leaves innumerable apertures through which attack may occur. Ex- amination and test showed that even “The Causes Porosity Electrodeposited Coatings, Especially Nickel Trans- sactions Electrochemical Society, Vol. 73, 1938, pp. Wesley, “Physical Properties and Uses Heavy Nickel Monthly Review the American Electro-Platers’ So- ciety, August, 1938, pp. 581-603. 32—THE IRON AGE, August 1939 heavier chromium deposits contain mi- nute cracks discontinuities through which corrosion could take place. Consequently, became imperative use some metal undercoat whose primary function would that protector, leaving chromium, the function decoration. And, number counts, the most eligible metal for this purpose was nickel. The conventional chromium plate, there- fore, consists undercoat nickel covered with chromium. this practice, the plate made really protective well decorative. variation commonly used ferrous metal layer copper followed coat chromium. From most the reliable data available, the porosity the plate de- creases with the thickness the metal deposited. Strictly speaking, course, porosity variable term; for ex- ample, hydrogen can forced through steel under sufficient pressure. How- ever, this discussion, porosity will understood “practical” aspect. Interesting data have recently been made public which throw much more the subject porosity, and may lead important changes manufacturing practice. For some time has been generally recognized among electroplaters that some ex- tent porosity caused impurities the plating solution and the deposit; also imperfections the basis metal. This has been corrobo- rated the work Hothersall and divided solid matter suspension the solution, foreign matter the surface the steel and rough con- dition the surface were the most important causes porosity nickel deposits formed unpolished steel. eliminating suspended matter from the solution and using specially prepared electrolytic iron finely machined mild steel rod the basis metal, they produced nickel deposits, pore-free (by the hot water test), less than 0.0001 in. thick. sure these results have yet been obtained only the laboratory, under the most delicately controlled conditions. They may, however, rep- resent only the first step which ually will followed commercial practice. the present time, one American firm, after long experience atmospheric protective plating, has announced specially treated deposit said substantially free from pores. Perhaps not too distant time, such deposits will produced the light thicknesses required for decorative coatings. The proof and general acceptance these seemingly elementary facts has led important development —the use heavy deposits nickel, much heavier than even the thickest decorative coatings, for industrial and engineering purposes, partly because their freedom from porosity but also because their excellent physical properties. Although metal theoretically can electrodeposited any thickness, from practical operating standpoint the application heavy plate brings with problems peculiar itself well the problems general all plating. addition being adherent and free from nodules, must have the strength, hardness and ductility required for the specific service under cast and fabricated metal. That these problems being solved manner suitable for prac- tical application industry has been shown the work Wesley’, who deposited nickel thicknesses 0.002 in. and over, pore-free ordinary tests, with some mechanical properties equal those wrought nickel and some physical properties, like electrical and thermal conductivity, actually su- perior the wrought metal. The ex- cellent results obtained impelled Dr. Wesley give the interesting name “cold castings” heavy deposits this character. The present uses for heavy deposits nickel are divided into three eral classes: a ee din j | ; yet tory, olled rep- rcial one ence has rom for ance (1) Electroforming—the direct production finished articles elec- trodeposition, which the deposit and stripped from the cathode for separate and independent use. (2) the dimensions part for repair salvage, the part having been worn (3) Corrosion protection heavy coating part the whole object prevent corrosion and heat oxidation, with without wear and fatigue. electroforming, generally the most important consideration the reproduction the design and dimensions the part coated. addition, however, the deposit must have sufficient strength hang to- gether unaided. may later backed but must have least fair amount inherent strength. Proof the availability these prop- erties exists electrotypes, phono- graph record matrices and medals. The fine details are perfectly reproduced and they stand the severe subsequent treatment inherent their use. More recently, electroforming has widened its scope include copper sheets thin gages which are now available commercially widths in., very long lengths and weights from oz. per sq. ft. (0.003 0.0094 in. thick). Kitchen utensils are being made bi-metal, for example—a saucepan drawn from sheet 0.031 in. thick, nickel one side and copper the other, nickel going the inside the part contact with the The latest development, wire screen made directly electrodeposition, important contribution present manufacturing practice. Such are obtainable any size design capable photographic repro- suit industrial decorative require- ments. The advantages include accu- racy the sizes the openings, wider range choice and control the relative sizes the metal and the apertures, the elimination crevices between overlapping wires, the elimi- nation the knuckles formed the overlapping wires, and finer gages and lighter weights. the food products industries, the absence crevices eliminates the danger catching and holding par- ticles the material screened, thereby minimizing corrosion and the breeding bacteria. photoengrav- ° ADOLPH BREGMAN Consulting Engineer, New York ing the smooth electrodeposited screen makes for better light concentration, preventing the dispersion and blurring light that take place through over- lapping woven wires. Electrodeposited screens are well suited for radios and earphones. useful variation this product the perforated metal strip with the per- forations appearing directly the electrodeposited metal, thus eliminat- ing the stamping operation. Radio and clock dials with the numerals ap- pearing very fine perforations are now being made this process. One the dangers ever present machine building mis-machining, the accidental cutting down parts undersize. Often possible re- claim such parts building them back oversize dimensions with elec- trodeposited nickel, and then machin- ing them down finished dimensions. This practice may represent consid- erable saving over scrapping the part. Instances savings this form reclamation are numerous expen- sive parts for high speed and precision equipment where building-up and re- machining will save piece from the scrap pile which has already had great deal work put into it. Similarly, parts worn down serv- ice which are expensive replace may salvaged fraction their cost. Heavy deposits chromium are widespread use surfaces subject hard wear but many cases has been found preferable build rapidly heavy supporting layer nickel and then cover this layer with thinner coat chromium. The list which follows shows some the parts which have been salvaged actual practice with heavy built-up nickel deposits: Armature shafts; compressor rods; pump shafts, sleeves, rods and plung- ers; textile spindles; hydraulic rams; valve stems; lathe beds dles; splined lithograph rolls and paper mill rolls; elec- tric motor end frames (mis machined) cams for viscose manufacturing ma- diesel crank- shaft expansion sleeves (superheated piston rod bearings; textile printing rolls; and turbine gear shafts. equipment for the power indus- try, heavy nickel deposits used this fashion have been more than ordi- nary service. The temperature cient nickel very nearly that steel, making nickel coatings highly suitable for service moderately high temperatures, such superheated steam, for example. Worn armature shafts can built without removing the windings. Salvaging worn refrig- eration compressor rods makes possible the stocking only one size gland packing instead carrying several smaller sizes fit the turned down rods. pump parts for corrosive liquids, the built nickel surface gives not only longer wear but also better resistance corrosion, does paper rolls and printing rolls. The high physical properties ex- hibited electrodeposits nickel add appreciably the length life the part, not only heavy applications but also with less extreme thicknesses, even where corrosion may accompanied some abrasion and erosion. With its good strength and resistance oxidation, nickel coatings can used steel quite high temperatures. Assuming proper ad- herence begin with, the bond improved heating. noteworthy fatigue resistance found steel THE IRON AGE, August kel, and use but cal the all ler ith rods, hard plated 0.006 in. which, under practical operating have exhibited high resistance abra- sion and also corrosion brines. These deposits are practically pore- free. equipment for handling and containing chemicals, nickel plate from 0.001 0.003 in. thick has been found highly satisfactory, even under con- stant exposure the chemicals. another instance, the alkaline storage battery, nickel plate used for resis- tance the electrolyte, caustic soda solution, even much lighter thick- nesses—0.0008 0.001 in. the out- side, and 0.0002 0.0003 in. the inside, with satisfactory performance. Still another case the nickel plate 0.002 in. thick the anodes the alkaline gas cells for making hydrogen and oxygen. such cases, course, freedom from porosity vital. general rule, industrial nickel deposits may used for corrosion, abrasion and wear resistance, equip- ment for contact with those chemicals which nickel will withstand, wherever the cost solid clad nickel would not justified. These conditions exist surprisingly large number in- stances plants working with such widely diversified products soap, rayon, gasolene, food products, like fruits and vegetables, dairies and meat packing plants, chemicals like alkalies, neutral and chlorides, carbonates, trates and acetates. Some the uses, both actual and proposed, for nickel plate, are highly specialized, but nevertheless (or per- haps for that very reason) interesting. The resistance nickel plate hot atmospheres (in which close second nickel-chrome alloys) has brought into use, 0.0001 in. thick, steel prevent scaling during anneal- ing and cold drawing operations. The plate itself much modified alloy- ing during these operations, but the surface the steel maintained much better condition. Where later finished baked-on enamel, the elimination the need for removing 7 4 a 4 the rough surface before enameling effects important saving. Another interesting use under con- sideration for coating hopper doors railroad freight cars. details are lacking but the plan success ful, will large feather the cap nickel plate. Substantial deposits nickel are used advantage machine parts. increasing extent brighten the machine, make more at- tractive the prospective buyer and also induce the user take better interesting, though old, application this type the plate bicycle sprock- ets. course, the primary reason decoration and freedom from rust. However, the plate also has stand severe abrasion where the sprocket engaged the chain; and although worn off more rapidly there than wear testing machine shafts. after plating 0.005 in. with nickel; center after chining the posited nickel; right —after cutting for key. The hardness the plate 400 elsewhere, still, the appearance (when good plating job has been done) not the plate does not chip, flake peel off. This type application might well turers for moving parts their equip- ment. The hardness nickel deposits varies with the composition the plating bath and the conditions operation. Wesley found the hardness soft nickel deposits plated from the conventional Watts bath 130 150 Vickers, and the hard nickel plated from bath, 350 450 Vickers. (For comparison, from acid bath runs from and chromium 500 900.) Table given Wesley, shows the mechani- cal properties nickel electroplate compared with other forms nickel. noteworthy that the properties TABLE Mechanical Properties Nickel Tensile Hardness Strength Elongation, Vickers Lb. Per Sq. Per Cent Cold-rolled, annealed 100 130 (B) 65,000 75,000 Cold-rolled, hard 180 230 (B) 90,000 105,000 Soft electroplate 150 (V) 51,000 Medium electroplate 230 (V) 98,000 Hard electroplate 360 (V) 132,000 TABLE Density Nickel (73.4 deg. Cold rolled sheet 8.86 Soft electroplate 8.86 Moderately hard electroplate 8.9! Hard electroplate 8.89 Form 34—THE IRON AGE, 1939 i | = 4 7. = a | ¥ 4 4 — — ‘ ad . | | | | TABLE Nickel Deposits Initial Time, Temperature, 325 400 295 325 one week 400 295 325 500 295 470 500 400 450 475 600 222 445 600 380 TABLE Soft Nickel Plating Solution Solution: Nickel sulfate (crystals) oz. per gal. Nickel chloride oz. per gal. Boric acid per gal. Temperature 140 deg. (electrometric) Current Density: amp. per sq. ft. (no agitation) 100 amp. per sq. ft. (with agitation) Hardness 140 160 Vickers (10 kg. load) in. per hr. amp. per sq. TABLE Hard Nickel Plating Solution: Nickel sulfate oz. per gal. Ammonium sulfate 2.8 per gal. Potassium chloride per gal. 5.2 5.8 (electrometric) Current density, Hardness, amp. per sq. ft. With agitation 400 450 nickel plate deposited from spe- cial bath compare excellently with cast and rolled nickel, and that the densities the nickel these forms are close together, shown Table Clearly, electrodeposited cast” nickel sound cold rolled “hot cast” metal. The hard nickel deposits can softened lower temperature than wrought nickel, because the high purity the metal deposited, its very fine grain