The Iron Age 1930-11-13: Vol 126 Iss 20

THE IRON AGE ESTABLISHED 1855 New York, November 13. 1930 VOL. 126, No. THE SECRET INDUSTRIAL GROWTH performs many miracles industry. few years may sufficient transform modest little shop into huge manufacturing plant where thousands labor. equally short period may sufficient shrink mediocrity completely dissipate the resources organizations that were once power- ful and flourishing. What the secret industrial growth? does not lie capital strength, for some today’s most successful concerns made their debut upon financial pittance. not luck. Good fortune may play important part times, but The secret successful growth lies the continual adjustment product, plant and policies the changing trends the times. makes the best speed who swims with the current. How is, then, that the responsible men industry shall have the clearest possible perspective industrial progress and its trends. The Seventy-Fifth Anniversary Number The Age, published next week, will present new perspective progress based upon three-fourths century intimate weekly contact with the metal- working industry. Its purpose give fundamental long-range view trends which will aid our readers interpreting developments and shaping successful policies for the future. 1363 | 4 4 ROUPING seven machines into production unit shown above. Three the presses are movable and are grouped, respect the four fixed-position machines and each other, form progre:sive stamping unit. This press line-up the Acklin Stamping Co. for the manufacture automobile brake dust shield. The press operator center, taking the disk from his machine, sends down the inclined runway the press which the succeeding operation done. Below picture taken the light-stamping department, showing four machines, all movable, grouped together two line, but all driven from the same line shaft, for progressive stamping operations small piece. ~ Ww 1364—The Iron Age, November 13, 1930 Migration Presses Into Grouped Production Units time-honored custom having all its press equip- and grouping several together temporary ment fixed position straight lines. OVING its stamping presses around the plant positions for ogressive operations Under the inflexible, fixed line-up, pieces often had production order novel and what might called moved considerable distance from one press revolutionary practice that has been adopted the for successive operations. Presses Acklin Stamping Co., Toledo, Ohio. job, under made neat appearance, but appearance this plant plan now followed, with the presses arranged for suc- cessive operations, kept ation until finished. Increased economies production resulting from greatly reducing the manual labor handling pieces process, the elimination large extent press helpers and the speeding output when sev- eral successive operations are required, caused the company abandon the moving from the first oper- has given way economies production methods. Contiguous location battery presses work- ing production order has made possible another ETHOD grouping machines effect econo- mies production. Two machines are placed side side right angles, permitting both presses bar connected both foot treadles. important saving handling costs, that presses unit, close positions convenient for work- ing, are connected chutes short elevators con- veyors that can moved from one line-up an- other. pieces are carried from one machine the next The Iron Age, November 13, 1930—1365 machine for the various successive operations. Another advantage the system that pro- vides production line and there constant flow production. Standard times are set for each job and one point, due break for change dies, the whole line usually stops, found rule that more economical shut down entirely than portion the unit under temporary operation. Stacking material the side the machine eliminated, stock awaiting operations one machine never being more than few pieces, take care slight fluctuation the production speeds adjoin- Group workmen are given two fatigue periods, one the morning and one the afternoon. The principal purpose this have the men leave their machines all one time, rather than inter fere with production being absent different Stock for job trucked, usually from the rail- oad car which brings from the mill, the first operation. the job about ready start, the material goes direct from the truck the first ma- chine. All presses are equipped with show the number pieces produced. Pieces scrapped because laminated steel other reasons are thrown the floor and picked hourly the salvage department. Those that can salvaged are put back production with very little quick salvaging, the company able maintain accuracy the quantity produced and avoid the loss stampings. The plant divided into two departments—heavy stamping and light stamping—located adjoining bays. The presses, all plain-type machines ranging capacity from 1000 tons, may divided into three classes. the heavy-stamping department there are nine pit-type presses strategically perma- nently located, and fairly large presses driven attached motors. These are moved around for use connection with the pit-type machines. The third group includes the small presses, about number, located the light-stamping department. These smaller presses are all driven from line shaft. Presses moved provide line-up for special range weight from 600 tons and have capacities ranging 400 tons. Presses from 400 1000-ton capacity are fixed positions. How the Presses Are Moved New Positions the presses from place place done quickly and easily. The plant has 2-in. wood- block floor laid concrete. The movable presses are anchored the wood blocks means four lag screws, one each corner the foot. While the weight the press helps hold position, the lag production job should run continuously for six eight months, sometimes happens, the lag screws are leaded into screws prevent any side movement. keeping pieces the concrete. registering production, stamping operations. These are two rows partment checking rejections and but are not line, and are all driven from one under hand lift for line-shaft. 1366—The Iron Age, November 13, 1930 + AN. . ing machines. times. — moving. gas-driven tractor used for hauling the larger movable presses, but more often the lighter presses, weighing 2000 are shoved around the floor hand without the use skids. The floor smooth and the oil-soaked wood blocks are quite slippery, that does not require great deal muscle push press from place place. The larger movable presses the partment are moved 10-ton electric traveling crane that serves this bay. provided this depart- ment for moving dies. Moving the presses provide line-up for new job usually done during the hour production not inter- fered with. supply range sizes take care any job speed kept storage for use the line shaft the light-stamping takes the millwright only about min. put new pulley, which usually done during the noon hour. Presses are grouped for progressive operations stampings whenever production order sufficient size warrant lining the machines for the par- ticular order. Usually the grouping done when order for 50,000 more small pieces, 10,000 more larger stampings. The movable presses the heavy-stamping department are grouped around the larger fixed-position machines. The permanently-lo- cated machines usually are used for first operations blanking blanking and forming. The pieces then one two the smaller machines for secondary operations, and then back one the larger fixed-position presses for finished Common press set-ups are three large fixed-posi- tion machines and two smaller movable presses, two the larger machines and three four the smaller, movable type. Usually machines are not grouped for only two-operation jobs unless the pro- duction order calls for long run. However, two-operation job take more than one day, necessary delay starting the job until suitable presses are available side side. Flexibility grouping machines accom- plished reversing quarter-turning presses, crossing belts and using belts different lengths required the location the machines. This also permits operating more presses from one line shaft than would possible were the machines perma- nently located along straight line. overhead air line has short drop connections frequent intervals and there are hose lines from the latter for connec- tion the presses, making air available any point which press may located. The press line-up for each job made the men out the shop who operate the machines super- vise production. They can best determine how the machines should grouped provide the most effi- cient arrangement. Perhaps after job started may found that the material may handled little more easily moving one machine few inches angle. OVING machines the work policy successfully practiced the Acklin Stamping Co. How stamping presses are shifted that they can most effec- tively work conjunction with others given production jobs described this article. The smaller presses, tons weight, are picked bodily and set where wanted. Flexibility operation, lowered handling costs, fewer helpers needed and speeding production are advantages obtained. in. wide. Examples Economic Grouping Presses the practical application the grouping ma- chines progressive production, pressed steel chain for coin-in- a-slot vending machine under production pres- cold-rolled strip stock links and when assembled in. long. The oper- ations succession machines grouped for the work are two locating points and blanking progressive die, these two operations being done one machine, tumbling barrel clean the surface and remove burrs, forming and piercing, two ma- chines being used for each these are slow oper- ations, and finally after assembling (the links being connected together with pins, manual operation), clinching the ends the pins press. This pro- duction job takes twelve employees, six machine oper- ators, one helper, four assemblers and one inspector. Daily output hr. for press operators and hr. for assemblers approximately 600 chains, the mak- ing which requires 36,000 38,000 stampings. In- cluding the pins the number pieces assembled approximately 76,000. One Operator Runs Two Machines Much ingenuity shown lining equipment speed output and reduce labor. this found press line-up that permits one oper- ator run two machines. Two small presses with automatic roller feed, one belt driven from line shaft and the other motor operated, are set close together right angles and flat wooden bar attached the operating treadle each press. With her foot the center the bar the girl operator controls both machines, starting and stopping the two together. The stampings being made these two presses are the two halves threaded ferrule. The stock, which fed the machine from reels, soft cold- rolled strip in. wide. combination cutting-off and forming dies the blank cut off and formed, the forming including bending the piece into semi-circle and pressing the thread, which extends the length the stamping. the two halves are not exact duplicates, one distinguished from the other be- ing stenciled during the press operation. The stamp- ings are made the rate approximately 4000 pieces hour the one girl operator two The Iron Age, November 13, 2 q 7 { F | q 3 4 | | JAMESON AXIMUM production cold-heading die depends five main factors, namely, die steel, die design, die heat treatment, bolt material and machine operation, stated Jameson, metallurgist, West Pullman works, International Har- vester Co., Chicago, paper Heading Die Life,” which was presented the recent meeting the American Society for Steel Treating the Hotel Stevens, Chicago. Mr. Jameson recited the results investigation, the object which was obtain the maximum production from die used cold- form cold-head plow bolt, which employed ex- tensively the farm equipment industry. Four Steels Investigated Four steels, designated and were for the investigation. Steel was the prod- uct open-hearth furnace, steel crucible furnace, and steel higher carbon melt from furnace. All four steels were plain carbon, but the composition steel was special interest, for had higher manganese content than usually found carbon tool steels for cold-heading work. this connection Mr. Jameson pointed out that Table I—Chemical Composition the Steels Stee] Carbon Manganese Sulphur Phosphorus 0.96 0.28 0.014 0.96 0.28 0.021 0.013 1.10 0.30 0.012 0.014 1.00 0.45 0.012 0.024 Table Effect Steel and Heat Treatment Production Heat Treatment Steel 1368—The Age. 1930 Per Cent Life Cold-Headin Die Depends Five Factors current metallurgical opinion not favor using manganese content higher than per cent high-carbon steel dies for cold heading. chromium content 0.10 per cent steel approached the range where chromium will modify the hardening properties carbon tool steels. The steels were ob- tained from the mills round bars an- nealed condition. The composition the steels given Table The bars were inspected deep etching, micro- scopic examination and hardness tests. Character- istics the materials were further determined quenching tests, carried out rounds machined from the bars, and later carburizing tests. Bars were heat treated being placed electric furnace temperature 1200 deg. F., and after equalization were heated rate deg. per min. the desired quenching temperatures, which occurred between 1510 and 1525 deg. for the lower heat and between 1610 and 1625 deg. for the higher. The rounds then were quenched per cent brine solution, the temperature which was Quenched bars were nicked flexible grinding wheel and broken for observation the fractures. Cross-sections were cut through the quenched rounds order measure the 1 (hromium 0.03 0.07 depth the hard case. The 0.05 depth was read off 1/64 in. 0.12 the polished and etched cross- section, the depth the case be- ing considered equal the ex- tent the martensitic structure. These measurements were supple- mented hardness readings. Surface hardness the 1-in. rounds was accordance with 4 | | 4 4 i} ( Steel Quenched 125 deg. Fahr. above hump held 20 min........ 11,100 10,54 Quenched from 125 deg. Fahr. above hump, Quenched from 225 deg. Fahr ibove hump, Not The figures give the average blank pi uct ‘ ends of tl previous findings, slight falling off hardness be- ing noticed when the temperature was increased approximately 1600 deg. The higher carbon steel showed soft spots the lower quenching tempera- ture and short hold time, emphasizing that he this type should held considerable time hea low quenching temperature used. Measure- ments the case depth the hardened rounds in- dicated that increase the temperature produced increase case depth, did increased holding time. Design Die Depends Shape Bolt Die design governed primarily the shape the die bolt, said Mr. Jameson, but there are certain modifications that are resorted order improve the die life. For example, was discovered that the forming small radius the corner the die more than doubled the die life. considerable in- crease die life was also secured rounding off the edge that part the die which forms the shoulder the shank the blank. When this edge was sharp, filed off the surface the bolt wire, the chips lodg- ing the corners the head the blank, thereby causing rapid deterioration the die. The dies were heat treated manner similar the rounds the hump method. Two quenching temperatures and two quenching times were used. Experiments showed that reason the increased mass die, compared with that l-in. round, the rate heating the quenching tem- perature must considerably modified. Moreover, important that dies heated uniform man- ner the quenching temperature. generally necessary obtain the proper rate heating for each individual die shape. the quenching process the dies were withdrawn from the quenching fixture while still warm. Said Mr. Jameson, “This precaution usually taken tool hardeners and have always found commendable practice. Many failures tools, both after hardening and during service, will result from cracks developed cooling completely. find desirable temper the dies soon possible after withdrawal from the quenching medium. considerable importance know within close limits what size changes take place during heat treatment.” Overwhelming Factors Are the Wire and Machine Operation Mr. Jameson declared that “as important the correct choice the steel and the careful heat treatment the dies, the most overwhelming factors are the wire and the machine operation. Un- less these variables can controlled within close limits the most careful heat-treated dies, made from the high- est quality steels, will break down comparatively short time. These fac- tors are the cause the most mislead- ing conclusions the best steel for heat treatment given case. the size the hole the die the first wire consideration. The analysis the wire has considerable effect the die life. Pure iron flows more object the in- vestigation, described this article, was obtain the maxi- mum die life from certain type cold-headed bolt die. Maximum production depends five factors: Die steel, die de- sign, die heat treatment, bolt ma- terial and machine operation. The important part played the depth the case emphasized. easily and hardens less cold working and conse- quently would ideal material this respect. increasing carbon content, because the effect carbon the flow and the hardness after cold working, materially decreases the die life. The wire used the experimental dies was the following analysis: Carbon 0.30 0.37 per cent, 0.50 0.80 per cent, sulphur 0.050 per cent (maxi- mum), phosphorus 0.045 per cent (maximum). “Manganese 1.25 per cent least does not affect the die life when the carbon under 0.20 per cent. Very successful die runs were obtained when using wire the analysis: Carbon 0.14 0.19 per cent, manganese 0.70 per cent. The physical properties the wire tension, especially the figure for the reduction area, cause material lengthening shortening the die life. reduction area value very desirable because guarantees rapid flow metal without rupture. reduction area value less than per cent preferred.” Surface hardness the wire some impor- tance, stated Mr. Jameson. variation hardness within short length wire detrimental, for (Continued on page 1436) Fig. bolt and the sequence manufacturing opera- tions, Left right: Wire length, first upset, blank, trimmed and finished bolt The Iron Age, November 13, 1930—1369 { Economies Result from Welded-On Overlays and Heat Treatment Wwe led- 1 lay ang } iT id ] es SSIDIE lan } mies nstruction msid ( re psolescence ol hir na ms: Cn Ma cninery 4 rts, stated Miles rer Aili cl ier at per > r ] j is i} presel Chicago the American Overlays Deposited Two Welding Processes Mr. Smith said that, strictly speaking, welded-on 7 verlay any metal- layer overlay at has been de- either the two autogenous fusion welding processes, but every-day practice has come mean overlay metallic alloy quite character from the metal overlayed. lays make pos- sible secure al- most desired surface any desired point over almost any de- sired area, provided the area overlayed will respond the autogenous welding process. the present time the need seems for sales promotion, Stoody Co., Whit- nted the recent meeting ROCEDURE and results series in- vestigations, extending over eight years, are given this article. Ascertaining the value welded-on overlays sur- over- face preparation for machine and other at- was the object. properly combin- welded-on overlays and heat treatments, possible sponsor greater economies machine and machinery construction and fabrication well considerably diminish the obsolescence machine parts. ing with the “Relationship less task. Tungsten ays and Heat Treatment.” porating tungsten have overlay which will pro- tect reinforce cast iron, wrought iron steel. most instances the overlay utilized with either car- bon, steel any one the more prevalent alloy steels. list all the metal- alloys elements which have proved some measure adaptable welded-on overlay compounds would almost end- and tungsten carbides have proved useful producing hardness, but alloys incor- other characteristics which Society for Steel Treating. are not all times desirable welded-on overlay Fig. soft steel upon which has been welded two rows overlay beads. The soft steel and overlay have been fractured and rough-ground along the center for more less general adoption. Likewise, silicon contributes hardness, and recognizable propor- tion silicon ferrous alloy will produce hard overlay. Yet such overlay may have tendency toward surface checking and brittleness that will quite undesirable. Chromium comes under the silicon. From perience gained the development far, has been con- clusively proved that more less com- plex alloy iron, silicon, carbon, chro- mium and one two other metallic elements, proportionate quan- tities that each will contribute its maxi- line each overlay deposit. This overlay has hard- mum strength, ness, after being welded on, from Rock- yet very little, well The overlay was made with the electric weld- any, ing arc and this view shows the comparatively smooth surface the overlay deposited Iron Age, November 13, 1930 nesses will form the best welded-on = n ] | | overlay for general resistance abra- throughout its use- ful life. The over- lay material must, sidelight par- application with welded-on overlay welding are the the fact that the materials marketed both. Further- fabricated welding layed must not rod. That is, they consist soft which held, un- smelted, mixture alloys and metal- lic and non-metallic elements well chemical reactory compounds. With such rod pos- sible during the welding procedure produce chem- ical reactions, some respects similar the thermit process forming weld. Welding rods utilized welded-on overlays have relatively higher melting points and melt down less readily than soft steel welding rods. With the electric welding arc, the overlay rod should used posi- tive electrode and with the oxyacetylene torch, the frame should free from uncombined oxygen and must played alternately upon the rod and the metal overlayed. Simplicity application the keynote welded-on overlays. Overlay Should Only Veneer every application, the overlay should only veneer. The most commonly used welded-on overlays are applied thickness from 1/8 3/16 in. their thinnest point, that is, the overlay ground smoothness, the finished thickness should less than 1/8 in. and more than 3/16 in. applied, the overlay should consist continuous layer overlapping welding beads. Necessity complete amalgamation between the metal overlayed and the overlay quite appar- ent. The true Fig. 3—On one side this specimen overlay mar- ketable welding alloy was deposited and the other side attempt was made overlay with alloy not compounded for the purpose. The piece was then fractured through the center. The difference the two deposits evident. The overlay marketable alloy shows grain quite similar appearance fine grade tool steel while the other deposit full holes and far from satisfactory damaged ened the process. Another phase overlay utilization, which often overlooked, the fact that either the electric welding are the oxyacety- lene flame generate heat some 6000 more deg. Fahr., and, the ordinary autogenous fusion welding operation, the heated mass fully ex- posed the action atmospheric agencies. This fact automatically eliminates many metallic elements from consideration welded-on overlay materials. Either they would too greatly affected atmos- pheric agencies they would volatilize under the in- fluence much heat. late, most successful ex- periments have been made along the lines welding hydrogen atmosphere, but the present-day cost such procedure prohibits from general use. Determining the proper elements and the proper proportioning each element for alloy utilized welded-on overlay entails the necessity determining beforehand exactly what the alloy will after has been exposed temperature from 3500 6000 deg. Fahr. under varying atmospheric conditions and with the operation under the control one who not versed metallurgy, perhaps only par- tially skilled welder. Two Types Heat Treatment Heat treatment may divided into two distinct divisions. One division includes those processes which have tendency ceedingly brittle, strength and one which throughout the unite with the metal which applied, that will re- place dary line main Fig. 2—View rough-ground section overlay shown Fig. The overlay easily distinguishable and the uneven boun- amalgamation between the two. been completely fused with the metal overlayed entire part be- ing treated. Ex- perience has the overlay and the soft steel the line evident that the overlay has over- (Cont. The Iron Age, November 13, 1930—1371 | ‘ : ‘ da \ Showing the portable bench-type com- parator arranged for inspecting screw threads. The operation its o simple, that a girl in pass or reject work ith certainty and dispatch has recent years passed period rapid development, brought the need for accurate and efficient ans for checking interchangeable machine parts. Chief among the developments are gages the optical contrasted with those the purely mechani- Fundamentally, both these types are alike ntrolled master gages and, interchangeable manufacturing concerned principally with the use rking and inspection gages, the develop- ter that one must look for the most rthy present-day achievements viewed the practical aspect. the operation gaging with any working nspection gage essentially that comparing di- mension dimensions the product, either directly indirectly, with those the master gage. this eration human and mechanical errors are encoun- and, consequently, any reduction them right ont these causes for error have tirely elin ated, and addition, the errors are directly the with many magnifications. How the Comparator Operates Among such optical measuring instruments the tor, which has seen sufficient service war- rant the conclusion that right principle. essentially inspection machine for measuring parts that must accurately gaged comparing the shadows, projected translucent screen chart, correct master and the part measured. 1372—The Iron Age. November 1930 Optical Measuring Practical hop Tools MARSHALL The Hartness comparator, built the Jones Lamson Machine Co., Springfield, Vt., consists essen- tially source parallel light, projection lens system, device for holding the work position front the projection lenses, and the chart screen upon which the shadows are projected. This chart has two outlines the correct form the work inspected the magnification used, one being spaced above the other distance equal the tolerance multiplied the magnification. The chart and master are adjusted till the outline the chart coincides with the shadow the gage, when the latter removed and the work tested inserted, and its shadow com- pared with the outline the chart. addition giving rapid indication whether and the photograph the top oppo- site page show jewel that forms the bearing 0.020-in. Swiss-watch pinion before and after magnification Hartness comparator, which was used for inspecting the concentricity the hole. ‘ 4 | DVANTAGES derived from using optical compara- tor contrasted with mechani- cal gages measuring screws, poppet valves, dental burrs and many complicated products are discussed this article. Speed operation and accuracy are among these. The comparator and how works fully de- scribed. the elements the work lie within the limiting di- mensions specified, the comparator has the advantage furnishing more detailed information the errors the work than usually obtained means mechanical gages. Particularly, furnishes more information irregularities form. Magnifications the work range from 200, according the lens system employed. The block lines the chart serve optical aid the matching the projected shadow with the master out- line. The source light incandescent electric lamp mounted that, set condensing lenses, practically parallel light secured, this light being lined all times with the optical axis the pro- jecting lens system. The objective lenses magnify and invert the image the work while the ocular lenses remagnify and reinvert the image. The compara- tors are either the bench floor type. The bench type especially suited for inspection small work, such screws; the larger machine for inspection larger work, such gears. object being measured mirror the back end the comparator and thence reflected back the chart directly front the operator’s eyes. the chart, readings may taken 0.0001 in. with the naked eye, the image being many times magnified. Screw Threads Can Tested described, the machine especially suitable for the testing screw threads for, this case, all that required pass inspection that the shadow the thread tested fall between the upper and lower outlines the chart. The chart consists outline perfect thread maximum pitch diameter, with parallel lines indi- cating thread minimum pitch diameter. The space between these parallel lines the tolerance which may vary according the class fit required. the shadow the thread displaced laterally, lead error shown; displaced vertically, variation pitch diameter the cause. staging device. ray light from ordinary automobile bulb shot across the object and through microscope, and the shadow thus cast thrown three teeth pair gears, using low-power lens system giving magnifi- cations. When properly staged, the gears are rotated and con- centricity pitch line, rolling action, etc., are studied. The examination may made be- tween two commercial gears between one commercial and one master gear. HOWING the contact all q 4 3 The Iron Age, November 13, 4 4 — | OST modern steel plants are large, highly in- tegrated centers manufacture. The main divisions include coke plant, blast furnaces, open-hearth plant, rolling mills and finishing depart- These huge modern plants need fuel vital raw iterial; fact, all plants are geographically located for cheap fuel supply. The glory Pittsburgh has its foundation the natural gas and oil wells Pennsylvania and the rich coal seams that crop out the hillsides the valleys along the Allegheny and the Monongahela. The major metallurgical fuels are gaseous form. Only the blast furnace tied solid fuel form coke, charcoal anthracite. Blast fur- nace gas, coke oven gas, producer gas, natural gas are the combustible gases available, with oils, tars and pitches, semi-gaseous (atomized) fuels also considered. Blast furnace gas was given some atten- tion article THE IRON AGE Nov. page Certain Gases Independent Demand Our supply blast furnace gas and coke oven gas not controlled the demand; their production de- pends the operation the blast furnaces and the coke ovens. These furnaces are large, and run even rate, very steadily. The supply blast furnace gas interrupted only “sickness” casting periods. The production coke oven gas more uniform yet, the individual ovens are clustered into batteries units. Storage these gases holders has been found impractical (in many plants). Natural gas was the ideal fuel the old days” that has grown scarce during the past years. Lately the enormous gas pockets the Texas and Oklahoma oil fields bring this fuel new importance. Producer gas made the spot, needed the furnaces. Coal, steam and air are the needed raw products and the B.t.u. remain stored the form the highly concentrated coal until the demand arises. 1374—The Iron Age, November 13, 1930 Mixtures for ulti-Fuel-Fired Furnaces JOSEPH SHADGEN Engineer, Smoot Engineering Co., New York Liquid fuels are always stored raw and atomized needed; the flexibility their supply im- portant feature. Producer Gas and Oil for Peak Demands The nature the supply these fuels makes advisable use blast furnace gas and coke oven gas for all operations that have base-load characteristics, while producer gas and oil are best suited for peak- load demand. This consideration has been grossly neglected far, account the lack coordina- tion and perspective between departments. comparison the prices these five groups fuels given Table which shows the narrow range values. Until recently all these fuels have been used is” alone, and engineers have tried find applications best fitted their value and flame characters. Fur- nace designs were very conservative; there the old story about “brick perpetuating old ex- perience well old mistakes. Lately the economic pressure has changed this conservative attitude. Under the leadership far-sighted management, en- gineers the Bethlehem Steel Corporation under- took some pioneer work with regard gas mixing. Successful mixing devices today operation handle all these gases available—producer gas, blast furnace gas and coke oven gas. The range and ratio problem have been solved adequate design the mixing apparatus. (See article Jan. 16, 1930, issue THE IRON AGE.) Blast furnace gas mixed with coke oven gas create varying mixtures having from 150 230 B.t.u. per cu. ft. This means volumes blast furnace gas volume coke oven gas, volumes blast furnace gas volume coke oven gas, for the two B.t.u. figures given. The ratio mixture determined the “pyrometric” character the fuel, best suited the efficiency the furnace. Soaking pits, tempering ovens, plate furnaces, annealing oper- ations are now economically handled with these mix- tures, simple furnaces adapted these new fuels. i \\i il} { Wy | 1287. Table I—Values Five Leading Metallurgical Fuels Blast Furnace Gas Unit cu. B.t.u. per unit Value per unit* Units per million 11,000 *1000 units, for the four gases. Coke oven gas has enriched producer gas, and mixture coke oven gas and blast furnace gas (175 B.t.u.) has been added producer gas burn open-hearth furnaces, thus eliminating one-third one-half the producers. Blast furnace gas has leaned out natural gas and created mixtures B.t.u. content comparable coke oven gas. One volume blast furnace gas and volume natural gas produce mixture 545 B.t.u., with different flame character from coke oven gas, account the different ratio coke oven, and shows the following comparison: B.t.u. per CO, co CH, Hy, Nz Cu. Ft. Coke oven gas.. 0.75 6.00 28.00 53.00 12.00 478 6.36 12.93 46.63 2.65 These mixtures were made the pipe lines lead- ing the furnaces. One apparatus serves battery furnaces and, gas pressures are maintained the same time, burners can set for definite results. This makes for simplicity installation and serves well many applications. Different Methods Burning Gases alternate solution offered when two more tuels are carried independently large furnace and burned jointly and simultaneously. This method demands that multi-fuel-fired furnaces equipped with apparatus regulate the air for all fuels, addition the proper draft control for removal waste gases. This development also sturdy youngster, full promise. Wisconsin Steel Works, South Chi- cago, Ill., and Hamilton, Canada (Steel Co. Canada), early attempts were successfully. Today over open-hearth furnaces operate more than one fuel. The combinations are coke oven gas and oil; coke oven gas and tar; blast furnace gas and coke oven gas; blast furnace gas, coke oven gas and IXING available gases produce metallurgi- cal fuel desired characteristics subject which has engrossed the attention many fuel engi- neers during the past two years. This article surveys the field with regard the principal available fuels, and shows how they may mixed for various pur- poses and how, finally, gas mixture any desired heating value, but with different characteristics otherwise, may obtained proper blending two more commonly obtainable gases. Producer Gas Coke Oven Gas Natural Gas Oil cu. ft. cu. gal. 145 500 1,000 150,000 7,150 2,000 1,000 6.7 producer gas; and blast furnace gas, coke oven gas, producer gas and oil (tar). Blast furnace gas alone not suitable for open- hearth operation account the low flame temper- ature, but, enriched with coke oven gas volumes blast furnace gas plus volume coke oven gas produce 195 B.t.u. mixture), good results have been secured. The art has not progressed sufficiently, furnace design has adapted the fuel features. But already can safely said that the economies realized pay amply for the expenditures. Either gas mixing multi-fuel-fired furnaces of- fer means utilize large quantities blast fur- nace gas open-hearth furnaces. Here the largest fuel consumer (4,000,000 4,500,000 B.t.u. per ton) available. Open-Hearth Can Use Only Part the Gas the surplus blast furnace gas per ton pig iron roughly 95,000 100,000 cu. ft., and this permits the production 90,000 cu. ft. blast fur- nace gas plus 30,000 cu. ft. coke oven gas 120,000 cu. ft. gas mixture, 195 B.t.u., some 24,000,000 B.t.u., aggregate, have enough refine ton pig iron produces, with scrap and ore, maximum tons steel, and usually about tons, appears that open-hearth furnaces cannot pos- sibly absorb all the surplus blast furnace gas, but big chunk can disposed metallurgical fuel great advantage. The remainder can used soak- ing pits and reheating furnaces, either alone jointly with other fuels. Boilers are used for burning all gaseous fuels over week-end periods, shutdown days departments, peak-load hours, Boiler plants (Concluded page 1436) q Al pa The Iron Age, November 13, 1930—1375 MY, being made the welding chromium iron and austenitic alloy was reflected the discussions the fall meeting the American Welding Society held the Congress Hotel, Chicago. Success Depends Design Welded Part his welding technique, however, seems depend largely the design the part ing being done commercial progress has also been rapid, considering the comparatively recent de- the alloys themselves. Hostettler, engineer, Allegheny Steel Brackenridge, Pa., extemporaneous address one the sessions discussed some the physical and electrical properties which complicate the problem. The extremely high coefficient expansion, low ther- mal coefficient, higher electrical resistance and other the alloy were shown call for very careful welding technique and the use suit- able fluxes, particularly those containing carbonace- ous compounds. difficult treat the welding from specific applications, said. Many failures are due the design the piece welded, which design might such build local work strains and other unfavorable conditions. For this reason, the Allegheny Steel Co. maintains department for consultation new applica- tions welding. cnar technique apart Straight chrome irons may either arc, gas, spot pression butt-welded. With oxy-acetylene, necessary use flame that slightly reducing, Mr. Hostettler said. this the welder must have the best kind equipment control the gas and air, otherwise excessive carbon will built the weld, causing embrittlement and lessening the corrosion re- sistance. Preheating Sometimes Advantageous The electric arc was favored for welding the alloy, except No. and lighter gage sheets, for which the gas welding more practical. short medium was said make sounder weld than long 1376—The Iron Age, November 13, 1930 elding Rustless Steels Making Progress For some pieces, preheating has advantages. serves offset the high expansion from the heat the welding process. Annealing after welding was recommended, although, the case the “18-8” alloy, not necessary all cases. Two methods are available. one, the most used for the straight chrome irons, the material heated 1425 deg. Fahr. and then air-cooled. the other, the material heated above its critical temperature about 1500 deg. Fahr. and then tempered. discussing this, Mr. Hostettler emphasized the fact that the alloy austenitic, outlined the change-over throwing out solution some the carbide that occurs adjacent the weld. When the alloy subjected temperatures ranging from about 1000 1550 deg. Fahr., annealing after weld- ing was recommended; the metal may put back into its true austenitic condition annealing mini- mum 1800 deg. Fahr., and cooling rapidly air water, depending upon the cross-section. For grind- ing the weld, special free-cutting soft wheel de- sirable order prevent buckling from excessive heat built the wrong type wheel. Need Annealing Depends Use Part The necessity for annealing the “18-8” alloy after welding, machining cold working was said de- pend entirely upon the use which the finished part product put. Apparatus for use connec- tion with hot sulphite liquor for such active electro- lytes nitric acid, for example, must annealed. was pointed out that, due the high coefficient expansion, great deal skill required weld long section light gage “18-8” alloy sheet and not have buckle. For this welding preferred be- cause quicker, and confines the heat much smaller area the sheet. When welding oxy-acetylene, jigs and chill plates are times necessary keep the piece being welded from running out shape. coated rod necessary with the are process, but not with gas welding. Rods having excess chromium and minimum car- bon are preferable, the higher chromium replace “evaporative” losses the metal adjoining the weld. The flux should such not add carbon. | use the rustless steels has nec proper welding conditions. This article brings gether some valuable data, based the recent experience engineer prominent company producing these materials. Success depends largely the design the part welded. Straight chrome-irons can welded any one four methods. Annealing welds important some cases. Material very light gage can welded only electric roll spot weld methods. Experience the Ford Motor Co. given. avoided, was said, except electric roll spot weld methods. discussing the brazing “18-8” alloys, Mr. Hostettler stated that had never seen done successfully production basis. Very little verti- cal overhead are welding these alloys has been done; this, great deal depends upon the flux and the operator. Practice the Ford Company this discussion, Chase, McGraw-Hill Publish- ing Co., told the practice the Ford company electric compression butt-welding 9-in. diameter stain- less steel headlight rims only 0.025-in. thickness. Both stainless iron and the “18-8” alloy have been used. first, after each run 200 300 rings, difficulties were experienced. One source difficulty essitated study was that metal strip was not uniform thickness from the edges the center. After considerable ex- perimenting with current, time welding, pressure, dies, etc., steel dies ground the surface were adopted. Today the daily production 15,000 rings, there are only rejects. After welding, the flash ground off and the welded rings are placed die, expanded and formed into the finished rims, then ground, polished and buffed. the case the “18-8” alloy, annealing necessary after welding as, with proper technique, this austenitic “18-8” alloy does not become embrittled adjacent the weld, the case with the straight chrome “stainless” alloy, which martensitic structure and air hardens above its critical tempera- ture, thereby reducing its ductility value the area heated above its critical temperature. Fire, Load and Sound Tests Battledeck Floor IRE tests the battledeck floor the subject comprehensive and extensive program now being carried for the American Institute Steel Con- struction the Bureau Standards Washington, determine the fire resistance this new type welded steel floor construction. Fire exposure will applied the floors from below twelve the test series, but six tests fire exposure from above will applied burning combustible materials, such wood and paper amounts from per sq. ft. floor area. Various degrees protection will given the upper surfaces the steel plate floor for these tests, from the bare plate series five types floor coverings. The test floors will ft. long and ft. wide. The beams will span the full 18-ft. length the floor except five tests where the beams will supported girder intermediate point introduce the details fireproofing required for the girder. Arrangements have been completed for series load tests, also carried out the Bureau Standards, under the supervision the engineering mechanics section the Bureau. These tests will con- sist strain gage measurements one panel, which will placed the restraining frame used carry- ing out the fire tests. One load test will develop the location the neutral axis the tee beam section. Determination will also made the intensity stress the upper surface the plate between beams gage length in. being used. About five gage lines parallel the axis the beams will uniformly spaced between adjacent beams located near the center the panel possible. Determination shearing stress the welds will made. The gage lines will placed the three middle plates the panel near one edge the panel practicable. The gage lengths used will in. and gage lines will placed the beam near the fillet joining the web the upper flange and the plates vertically above these gage lines. this panel the yield point will arrived increments lb. per sq. ft. then increments the point failure. Arrangements have also been made with the sound laboratory the Bureau Standards carry out series six tests battledeck floor panels, each with variation ceiling protection and floor covering. The Iron Age, November 13, 1930—1377 Internal Stresses Hollow Cylinders Tool Steel Estimated EVELOPMENT method for estimating the internal stress quenched hollow carbon steel cylinders and its application two dis- tinct types quenching were discussed Greene, Carpenter Steel Co., Reading, Pa., paper entitled “Estimation Internal Stress Quenched Hollow Cylinders Carbon Tool Steel” the recent annual meeting Chicago the American Society for Steel Treating. Hollow cylinders were chosen be- cause they represent the ideal forms drawing cold heading device which the most important tangential and rather than axial. Submerged Flushing First Method Used number cylinders, varying length from in. in. and having diameter in. with hole, were quenched submerged flushing 7<¢ \ \ af | — 2 A Cylinders quenched flushing the hole 1600 deg. Fahr. Rockwell hardness points shown. Note the uniform hardness penetration opposite page 1378—The Iron Age, November 13, 1930 various temperatures. Certain specimens were sub- sequently tempered. The remainder the specimens were flushed the hole only. Quenching difficulties encountered flushing the hole were overcome using simple quenching device. Two stainless steel disks, in. thick and in. spreader was peened the bottom disk. Asbestos washers were placed between the cylinders and disks, and the whole clamped means stainless steel bolts and nuts. The holes the disks, corresponding the holes the cylinders, were tapered admit the tapered nozzle the flush the top and allow unrestricted flow the bottom. The disks and cylinders after assembly were placed the furnace and heated the required tempera- ture. The quenching operation consequently was Cylinders quenched submerged flushing 1600 deg. Fahr. Rock- well hardness numbers are shown. Note cylinder, in. long, hardened through this tempera- ture. (below a 35 » 34 \ \ \ 14 a 57 4 \ \ 3 | | 4 a 4 ~ author describes two widely different methods determining internal stresses hollow cylinders carbon tool steel. The two methods are sub- merged flushing and flushing the holes, when the first case, the stresses the holes such cylinders are either tangential tension tangential tension and compression com- bined. the other case, the stresses are uniformly tangential compression. Relative advantages are pointed out. simple. The device containing the cylinder was re- moved from the furnace, the nozzle the flush in- serted and the water turned on. The fit between disks and cylinders prevented the flushing the top bottom surfaces. The alinement cylinders with respect the spreaders was always perfect. The gradation hardness from the hardened zone outward cylinders flushed the hole 1600 deg. Fahr. was much less than those flushed 1450 deg. This undoubtedly one reason, said Mr. Greene, why the hardened surfaces dies that have been flushed 1600 deg. not tend sink readily those dies quenched lower temperatures. Mr. Greene found that, after submerged flushing both 1450 and 1600 deg., all lengths cylinders are bell-mouthed. That is, the middle the hole de- creased size while the ends expanded. The dis- tortion greater 1600 deg. than 1450 deg. After tempering 450 deg., the bell form persisted, but both the ends the hole and the middle showed considerable decrease diameter. Different Results When Flushing the Hole Flushing the hole presented entirely different results. The holes were but slightly warped and both the ends and the middle showed uniform decrease diameter with all lengths both 1450 and 1600 deg. the former temperature the holes the 34-in. and the 3-in. cylinders and the latter tem- perature the holes the and cylinders Results first attempts flush the hole only. The cylinders failed complete cracking when room temperature was reached. The lower half the figure shows the nonuniform hardness penetration obtained and the Rockwell hardness numbers. Flushed hole 1600 deg. Fahr. actually had less decrease diameter the middle than the ends. This caused slight warping direction opposite that the cylinders quenched submerged flushing. The cylinders flushed 1600 deg. revealed greater decrease hole diameter than those flushed 1450 deg. Tempering 450 deg. further decreased the diameter the holes. Mr. Greene discovered that there was considerably more bending the outside diameters cylinders quenched submerged flushing than those quenched the hole. Tempering 450 deg., however, reduced the bending after both methods quenching both temperatures. The changes lengths all speci- mens were greater the hole, causing distinct crowning each end. These changes increased slightly with higher quenching temperatures with both methods quenching. However, the changes length after quenching both methods 1450 and 1600 deg. decreased with th