The Iron Age 1930-11-06: Vol 126 Iss 19

THE New York, November 1930 ESTABLISHED 1855 126, No. Detailed Records and System Grading Used Rate Apprentice’s Work Cooper-Bessemer Corpn., Mount Vernon, has successfully conducted apprentice training school. Monthly records and system grading are used establishing efficiency ratings for apprentices and from the data obtained charts are prepared that form permanent record the stand- ing each student. Boys admitted the apprentice training school must years age, physically fit, mechan- and good character. Boys with high school training, least with knowledge mathe- matics are preferred. When accepted, they probation for month before being regularly enrolled students. Under the direction the school in- structor they are given preliminary training the operation various types machine tools the apprentice department, which separate from the production department and fitted with the various types machines used the plant. Here boys are tested for their aptitude for machine work and are given training preparing them for the production shop. Class room work given the instructor Saturday morning and the apprentices are allowed regular wages for that time. Lessons used are sup- plied the Pennsylvania State College. Membership the class limited present about 20, being kept low that the boys can permanently retained, department set aside from the main shop the apprentice given his preliminary training different types machine tools 1279 since contrary company policy lay off ap- prentices during periods ‘depression. 7200 hr., three years’ time the shop and class room. Over- time credited the apprentice calculating his hours service arid time absent deducted. The entire apprentice period divided into nine wage ad- justment periods 800 hr. each. The boys start 24c. hour and are given 2c. increase the be- ginning each succeeding period, receiving during the final period hour. addition the company deposits the bank month for each apprentice. These instalments, which bear per cent interest, are sufficient number amount lump sum $100 the completion apprenticeship. part this amount given the apprentice until completes his training The purpose this additional re- ward impress the boys the advantage sav- ing. the same time may have tendency hold boy, should develop inclination leave the school. The company also pays for the boy’s college text course and supplies him with tool box containing the tools required his work. The total pay received the boy during his three-year training $2,304. Apprentices are frequently transferred from one machine another with view giving them all about equal number hours each machine, that each will have complete training the operation each the ten types standard machines used the plant. The apprentice course requires about show his efficiency shop work and the class room, complete record each kept during his training course, after his month proba- tion. This starts with monthly apprentice record made out the instructor (chart A), which the boy’s shop record, school record and record the hours spent during each day each type machine. His shop record covers conduct, interest, aptitude, confidence, accuracy, speed, neatness and APPRENTICE GRADE /NDEX APPRENTICE RECORD NAME APPRENTICE SHOP RECORD SCHOOL RECORD CHART days absent and times tardy. system grading provided the use grade index scale (chart B), atid apprentice graded letters according the average mark that has been given him for speed, conduct, etc. Grading for speed made from the apprentice’s time cards, which are based the same time studies that are used the produc- tion department. get 100 per cent speed rating apprentice must time set time study. Each item the grade chart given SUPERIOR AVERAGE poor itidicating the relative im- GRADE portance each qualifica- VERY QUICK LEARNS SLOW DENSE 100 per cent record down AA io 176 SELF- wy 7 7 ACCURATE school INACCURATE CARELESS age rating. The also tabulated record SPEED | VERY RAPID ¥Vi75| RAPID 10.75 AVERAGE 975} SLOW 7.75| VERY SLOW \675 on the monthly apprentice UNU ERY NEAT NEAT CARELESS record arid indicates the CHART Iron Age. November 1930 one-half the same chart the number hours | | MONTHLY APPRENTICE SHOP RECORD NAME APPRENTICE REPORT MILLING YEARLY MONTHLY EFFICIENCY CHART 328 writer’s results are based were carried out the elec- tric blast furnace cleaning plant.of the Elga type the Mannesmann Tube Works, Huckingen, Germany. The author presents curve showing the working, plotted, which revealed what the moisture content the gas had relation its temperature entering the purifying chamber order secure the best possible result. The maximum temperature limit for the electric removal dust from blast furnace gas purity 0.02 grams per cubic meter was found deg. and purity 0.1 grams, 110 deg. The most favorable range temperature for regard higher gas temperatures, the writer points out the necessity far-reaching pre-cooling treatment. The power consumption per 1000 meters dried gas over 0.35 kwhr. and 0.55 kwhr., in- cluding the pre-treat- ment the gas. The PEDO writer therefore con- tends that the eco- nomic superiority the electric purifying process has been fully demonstrated. Expenditures rolling mills and steel text. States 0.04 per cent vested, according apprentice served different machines listed for each day the month. For ready reference the Dr. Frank Parker, professor finance the Wharton School Finance and Commerce, phia. The average for all industries for which data are avail- apprentice’s monthly able 1.03 per cent. record transferred permanent rec- ord, which shows boy’s standing almost glance. Another (chart shows each apprentice’s grade for each month and for the previous full year. Electric Cleaning Blast Furnace Gas influence exercised the physical and chemi- cal composition blast furnace gas and dust the electric cleaning process the subject article According abstract the London Jron and Coal Trades Review, the investigations which the CHART The figure for chem- ical and allied prod- ucts, most, 2.04 per cent. address be- fore the American In- stitute Steel Construction, Pinehurst, C., Oct. 28, Dr. Parker urged the extension research programs cover production, marketing and distribution well the technical, and said plans should laid terms ten-year periods, such are calculated “to obviate the needless changes tonnage and profits.” Quoting the most recent compilation the National Research Council, pointed out that all in- dustries have average annual research expenditure per plant approximately $50,000, and that rolling mills and steel plants spend $16,200. The Iron Age, November HOURS SERVED DIFFERENT MACHINE TOOLS 6 = Qa & |] | 4 6.MILLS 345 4 Chase brass and copper mill Waterbury, Conn., nearly a mile long. Vari- ous shapes extruded brass rods (Insert) Iron and Steel Used Modern Brass and Copper Mill KESHIAN Metallurgist, Chase Companies, Inc. Waterbury, Conn. RASS and copper mills, representing one the oldest groups metal-producing industries, have always used iron and steel the construc- tion their equipment. Therefore, much the me- chanical improvement which the engineer was able introduce into these mills has often depended the development iron and steel better physical prop- erties. would interesting, therefore, consider, general way, some the uses these metals this pioneer industry for its various operations. the Casting Shop the melting brass and copper, whether the crucible the modern electric induction furnace, the molten metal has stirred and the dross must skimmed off before pouring. For this purpose bars wrought iron and sticks graphite suitable size were used. Wrought iron not being fragile like graph- ite was much preferred; but always presented danger contaminating the metal going into solu- tion with it, which required extreme caution the part the melter. Low-carbon high-chromium iron has now been found far superior wrought iron this respect, re- 282—The Iron Age, November 1930 ducing the danger contamination minimum. But there still need for material which, besides being resistant the corrosive action brass and copper, will not become unduly brittle repeated use. There are very few things the casting shop modern brass and copper mill which the melter care- fully guards the correct casting temperature his metal. account the interfering fumes the metal, optical pyrometer cannot used advan- tage, and pyrometer with its fire end immersed the molten metal must used. Pyrometer protecting tubes made high-chromium iron, when used inter- mittently, will found satisfactory. But for pro- longed use, that is, where desired leave the fire end the instrument the furnace indefinitely, satisfactory unfragile material for protecting tubes has been found yet. For mold material, the brass and copper melter uses the gray iron ingot molds, and some his prob- lems connected with these molds are identical with those his brother melter the steel mill. Un- questionably the future. material changes will take place both the design and the manufacture present gray iron molds and probably new mold metals, with services commensurate with their cost, will developed. the Rolling Mill scalping, overhauling and milling cast and rolled bars and ingots, high-speed steel seems hold its favored position virtue its combining itself good wearing property with ability retain its hardness these relatively low frictional tempera- tures where other types steels lose their hardness. the rolling copper and brass the progressive manufacturer has been alert the advantage not only better methods rolling, understood today, but also the quick adoption better materials for various rolling mill operations and equipment. some instances, course, the rate with which has been able adopt better material for different equip- ment, such rolls, gears, pinions, shafts, chains, etc., has necessarily depended the progressiveness and readiness the rolling mill machinery manufacturers substitute better material new processes their product. Competition here also has been playing its role, beneficial all concerned. Thus cast iron gears and pinions are being gradually supplanted cast forged steel and heat-treated ones, and soft steel shafts are being replaced alloy steel ones. Steel Versus Iron Rolls Use steel rolls for breaking down and finishing operations the modern brass and copper mill slowly but steadily gaining ground. Where the final cost, the ultimate economic value, steel rolls over that chilled iron rolls has been established beyond doubt, their adoption, whole, has not been slow. present, undoubtedly better steel rolls are being made and the rate with which they will used over tion-type electric furnaces for melt- ing brass and cop- per, equipped with control in- struments. High- chromium iron skimming bars used ming off the dross foreground required today, but also what may needed tomorrow, the way ferrous products for brass and copper mills, the burden the accom- panying article, which adds materially literature marked paucity. The high spots: the Foundry: Rustless steel and gray iron ingot molds. the Rolling Mill: replac- ing chilled iron rolls, plain carbon and alloy tool steels for shearing, alloy steel for cold drawing equipment, such chains, dies, etc. Hot Working: Four types alloy steels used, heat treated. Hot Piercing and Forging: Several kinds steels use. Extrusion Die Steels: High and low tungsten high-speed types generally used. will quite logically depend their relative cost and ability prove their economic value over the chilled iron rolls. For cold shearing slitting sheet brass and copper, standard type steel chemical composition found. Among the types that are used may mentioned plain carbon tool steels, carbon-tungsten and carbon-chromium. Freedom from loading with The Iron Age, November 1930—1283 drawing brass and copper. For cold drawing, iron and steel are used many different forms the metal and absence quick wearing and chipping are the essential requirements for these cutters, which requirements are generally controlled the micro- scopic structure, the hardness and the finish which the slitters receive during the process their manufac- Heat-Treated Alloy Chains Now Used For cold drawing equipment for tubes, rods, and shapes various designs, iron and steel are used different forms, such draw bench frames, chains, carriages, dies, plugs, arbors, etc. Heat-treated alloy steel chains made either chromium-nickel, chro- mium-vanadium pearlitic manganese steels, are definitely proving their superiority over the old-time medium carbon steel chains, often used natural condition. draw bench chain, crude may seem, con- stitutes one the vital parts cold drawing equip- ment metal working plant and the manufacturers this type machinery have excellent opportu- nity bring this equipment its highest efficiency applying our latest knowledge the development physical properties metals, with definite edge the proper limits for breaking strength, yield point and elongation which the chain should possess under known conditions operation. the other hand the user can best cooperate with the manufac- turer putting before him his own needs definite- RAWING large brass and copper tubes powerful hydraulic presses. Another property, which often the de- termining factor the choice steel for drawing dies, the readiness with which the steel can shrunk back size after the die hole has become too large Bel! wf pe... 1284—The Iron Age, November 1930 specifying the maximum pulling capacity required the chain without yield elongation with given factor safety. For draw bench grip jaws, properly heat-treated plain carbon alloy used. these members are subject shock well steady straight pull composition having maximum tough- ness with reasonable hardness should selected. Steels Best Suited Cold Draw Brass Regarding the characteristics steel that would best suited cold draw copper and brass, there perfect understanding between the steel maker and the user, namely, that the steel must have maxi- XTRUDING brass rod the bury. presses are capa- ble exerting 80,000 sure per sq. Into the large al- has just been mum wearing properties without tendency scratch the work. Now, the chemical composition steel which will fulfill these requirements does not seem clear. Some prefer per cent plain carbon steel, others from 1.10 1.20 per cent carbon steel and still others some alloy steel mostly the tungsten type. But experience shows that even 0.80 0.90 per cent carbon steel will make good drawing die. Among the many different types alloy steels rec- ommended used for drawing dies are, carbon-vana- dium, ‘carbon-chromium, both high-carbon high-chro- mium and low-chromium and high-carbon, carbon- tungsten steels. Another property, which often the determining factor the choice steel for drawing dies, the readiness with which the steel can shrunk back size after the die hole has become too large. Some the alloy steels not shrink and many them shrink but slightly, making necessary either re- forge the die back size make new dies; and the schedule operations for various draws does not al- ways permit the use dies them dies larger holes. This limited degree shrinkability alloy steels disadvantage against them when they are used for drawing dies and means can overlooked. Under certain conditions, however, will decidedly better use alloy steel dies, particularly for finishing operations. Difficult Select Steels for Drawing Dies The choice proper steel for drawing dies becomes even more difficult when other factors besides the chemical composition the steel are considered. For instance, well known, steels made two different mills, even though identical analysis, not always have the same quality, soundness, the same satisfactory microscopic and macroscopic structure, the same degree responsiveness heat treatment, etc. For drawing brass and copper wire, chilled iron, tungsten carbide, diamond and hardened, and soft steel dies are used. Soft steel dies—usually those alloy steels—are freer from heat checks and can peened back size reforged size. Hardened steel dies are better suited for finishing operations because they can maintain their size for much longer period than the soft dies. Generally speaking, alloy steels having from 1.25 1.35 per cent carbon, from per cent tungsten, per cent carbon and per cent chromium, per cent carbon and per cent chromium give sat- isfactory service for larger sizes wire and wire The Iron Age, November 1930—1285 rod. For relatively small wire, diamond, tungsten carbide wortle steel preferred. Steels for Hot Working the hot working brass and copper the types steel used are not expected fill more strict de- mand than for hot working iron and steel, except perhaps the operation hot extruding brass and cop- per. Excluding the latter, the stresses the rolling, piercing forging shape, are not whole any greater than those for the similar operations for iron and steel. Furthermore, the maximum hot work- ing temperature for brass and copper about 500 deg. Fahr. lower than for iron and steel. But, con- trasted this, there this fact that, generally, the hot forged brass and copper parts are such that they require more exacting dimensions and finish than those required iron and steel parts. This means that the dies must hold their size and shape closer NSPECTION brass and copper tubing. The chief desirable charac- teristic the steel for drawing dies maximum wearing property without tendency scratch the work and freer from heat checks greater extent than the dies used for iron and steel forged parts. Ob- viously, for operations this nature, hot working steel, the best type respect these requirements, has used. the other type hot working brass and copper, namely, the process extrusion, the pressure may run high 80,000 per sq. in., requiring steel the essential characteristic which must maximum resistance compression deformation billet temperatures varying from 1300 1800 deg. Fahr. addition these requirements that are expected the steel used for hot working brass and copper, forging, rolling, piercing extrusion, there are other considerations, some which, al- though not peculiar hot working brass and copper, (Continued page 1359) type 1286—The Iron Age, November 1930 steel position found Blast Furnace Gas Metallurgical Fuel JOSEPH SHADGEN UEL problems offer the greatest field for improve- ments modern steel plants. Combustion its broad aspects will demand greater attention and more concentrated effort reduce costs lower figures. Production problems will yield first place questions costs and quality. Modern plant economies demand that the term product” wiped out. necessary create over- all maximum efficiency, that all products every metallurgical process considered even basis contributing values. For instance, blast furnaces not only produce cast iron, but they yield three major products: Cast iron, slag and blast furnace gas, which have valued their highest rating. true that the blast furnace primarily ore-reduction furnace, but this possible only making gigantic gas pro- ducer well. While pig iron has ready value, has the slag. Ever-increasing markets have been opened this material—long considered waste and burden. Crushed slag used railroad ballast, road-mak- ing material, and raw product for bricks and arti- ficial stones. Blast furnace slag can used advan- tage raw material Portland cement kilns, and for insulating, mineral wools, etc. develop these manifold industrial applications successfully, commer- cial vision was necessary, with the tenacity over- come the technical difficulties pertaining the adapta- tions each specific use. Importance Blast Furnace Gas Blast furnace gas the third product the process reducing ore into pig iron. Its importance un- deniable; its volume enormously large, although its unit heat value low. Roughly per cent the heat content the coke charged with the ore leaves the furnaces the form gas. safe say that the production every ton pig iron yields also 130,000 140,000 cu. ft. gas which, B.t.u. per cu. ft., makes some 11.75 12.5 million B.t.u. This equivalent 800 900 high-grade bituminous coal and permits genera- tion 700 800 kw.-hr. Typical analysis the gas volume and its major properties are: Per Cent Combustibles, 28.9 per cent. 71.1 per cent. Higher heat content, 93.5 B.t.u. Lower heat content, 91.8 B.t.u. Density 1.05. One volume gas needs 0.68 volume air, and with per cent practical excess, 0.75 volume air, for combustion. Heat content unit gas and air mixture 52.5 B.t.u. The Iron Age, November 1930—1287 Advantageous utilization this large fuel value gaseous form demands not only cleaning but thor- ough cleaning, permit reliable and safe, easy and economical, distribution. The past years devel- opment the art has demonstrated not only that cleaning pays its way but that makes higher-grade uses possible. Hence cleaning extends the application the blast furnace gas and increases the unit value the gas. Methods cleaning blast furnace gas have been developed high degree; the cleansing process progressive, removal the coarse dirt settling chambers and the fine the secondary processes. All principles have been applied, wet and dry, filtering bags, centrifugal, electrical. today universally accepted that cleaning costs are recovered increased value gas. Major uses blast furnace gas are: Stoves. Boilers (power production). Metallurgical furnaces and processes. Stoves being necessary adjunct the blast furnace, their quota comes first. Modern stoves re- quire from per cent the gas produced, some 32,000 42,000 cu. ft. per ton pig iron. This equivalent 2,900,000 3,800,000 B.t.u. While may argued the old-time operators that stove efficiencies have not been materially in- creased gas cleaning, cannot denied that clean gas made modern stove design possible, with logical brick design, less brick weight, greater sur- face and fewer stove units. This means less capital tied and less maintenance operation. Less than 3,000,000 B.t.u. for air preheating requires clean gas and modern stoves. Huge Surplus Gas for Outside Uses Hence, the surplus blast furnace gas available for other applications than the ore-reduction process itself about per cent, meaning roughly 95,000 100,000 cu. ft. per ton pig iron, and equivalent some 8.5 9.5 million B.t.u. This enormous surplus gas should used yield maximum returns. Returns mean dollars, but not necessarily process efficiency. Local conditions must duly appreciated and considered determine actual values. Developments should based the guidance furnished the technical aspects the diverse applications possible. present some interesting realities critical form attempted herewith: date most the surplus gas has been burnt under boilers generate steam for electrical power production. boiler fuel the gas com- petition with coal. advantage process Hence blast furnace gas substituted for coal boiler fuel. Ninety-five thousand 100,000 cu. ft. gas 1288—The Iron Age, November 1930 685 lb. coal (13,000 B.t.u.). The best values figure between and 2c. per 1000 cu. ft. blast furnace gas. This means that the surplus blast furnace gas available per ton pig iron has value $2. This value checks the fact that 500 kwhr. can generated per ton steel. Based 0.3c. mills) per kwhr., this represents $1.50, the mean between the extreme values given. kwhr. 16,000 17,000 B.t.u.) (550 16,500 9,075,000 B.t.u. total) The reasons for this low value the blast fur- nace gas are the nature the steam-generating process. Blast furnace gas too lean, requires large combustion chambers, has low flame tempera- tures and needs large induced draft fans, large mo- tors and high power consumption. Efficiencies burning blast furnace gas under boilers seldom ex- ceed per cent modern plants, while coal efficiency averages per cent under parallel conditions. Hence boilers offer only solution, not economical one. Handy, because any surplus may dumped into the power house and absorbed short notice. Hence boilers must equipped for both gaseous and solid fuels (lately, combination pulverized fuels and gas have become very popular). Metallurgical Fuels Most metallurgical processes require clean fuel not contaminated with impurities (ashes), which sulphur the most objectionable. This limits solid fuel (coals) and makes gasification processes neces- sary make sulphurless fuels available. That caused the invention gas producers, water-gas sets, etc., produce gaseous fuels better suited than the solid coals for multitude applications where heat necessary steel plants. Producer gas made partly decarbonizing coal, with and the main constituents very similar blast furnace gas, but somewhat richer B.t.u. content. Its characteristics follow: Per Cent 20.5 12.5 Combustibles, per cent CH, 3.0 7.5 56.5 Inerts, per cent Higher heat content, 147.8 B.t.u. Lower heat content, 138.7 B.t.u. Density 0.9. One volume gas needs 1.1 volumes air, with per cent practical excess air, 1.25 vol- umes. Heat content gas and air mixture, 66.5 B.t.u., about per cent richer than blast furnace gas-air mixture. Producer gas the standard metallurgical fuel used coke ovens, open-hearth furnaces, soaking pits, heating furnaces, etc. The equipment required for the manufacture this gas are gas producers costing $25,000 $30,000 each for standard size, (4000 5000 per hour capacity), requiring coal handling, ash handling, soot chambers, space and maintenance. The efficiency the cycle per cent, depending use sensible heat the producer gas, the location producer house rela- tion furnaces, etc. UTTING costs through using erstwhile waste material has been major indoor sport American industry during the past decade. Sometimes these materials are not en- tirely waste, whereupon better utilization them sought. this article the subject blast furnace gas metallurgical fuel sur- veyed with regard number present and possible uses. Limitations are pointed out and shown how, certain enrichment the gas, can made serve much higher pur- pose than those which customarily put. The cost producer gas made price coal, steam, labor, maintenance, interest, amortiza- tion, etc. Experience shows that all these charges can lumped and quoted surcharge coal values, say per cent coal cost. Roughly speaking, gasification charges run between $1.25 and per ton coal. 21,600,000 13,500 2000 27,000,000 0.8 150 B.t.u. 145,000 cu. ft. gas. Cost per 1000 cu. ft. varies between and 4.5c., based coal prices vary- ing between and $4.50 ton. From these data appears that, blast furnace gas can used for competitive purposes applica- tions where producer gas ever used, the value the blast furnace gas can thus increased 100 per cent, compared with its use boiler fuel. other words, the blast furnace gigantic producer and should utilized such. 600-ton day blast furnace generates the equivalent sur- plus gas gas producers (3000 4000 lb. hour). 1000-ton blast furnace can deliver enough Transformation cost blast furnace coke into blast furnace gas utilized great advantage for ore reduction, instead being waste, the gasification process the producer. seems most logical, therefore, put blast furnace gas work metallurgical fuel wherever conditions indicate successful combustion conditions. review the possibilities given. For Coke Ovens The high-temperature coking process opera- tion requiring exchange heat refractory chambers temperatures between 1500 and 2500 deg. Producer gas has proved good fuel, has coke-oven gas. Blast furnace gas has been demonstrated ideal substitute. Unfortunately, this requires rebuilding the coke ovens and addition gas checkers. That calls for large capital outlay, which eliminates this application old plants until batteries are re- built, for obsolescence. For new plants essen- tial consider blast furnace gas-fired coke ovens having good chance show saving. Reliability blast furnace gas supply essen- tial, which limits this application still further those plants having more blast furnaces. For Open-Hearth Furnaces Melting and refining pig iron, ore and scrap open-hearth furnaces requires the highest flame tem- peratures used any industrial furnace—3000 3500 deg. Iron melts 2700 2850 deg. Blast furnace gas alone cannot possibly fit this condition, spite preheating gas and air. But substitute for producer gas, admixture other richer fuel (oil, coke oven gas, natural gas), offers remarkable possibilities. Experience has shown that the practical facts bear out the theoret- ical calculations. Results pioneer work along these lines will reported later part this study. For Soaking Pits, Reheating and Heating Furnaces Reheating processes require metal temperatures between 2200 and 2450 deg. assure plasticity and reduce the power required for shaping, rolling, forging, etc. Blast furnace gas fits these applications like glove, with without gas preheat, but always with air preheat either regenerators recuperators. The softness the blast furnace gas flame, the leanness the gas-air mixture, are extremely well suited the furnaces, and these uses are bound extend further experience accumulates and the furnace designers adapt their construction the characteristics the blast furnace gas. For Normalizing, Annealing, Drying, Etc. heat-treating processes the temperatures are relatively low—usually less than 1600 deg. The qualities blast furnace gas fuel are still more adaptable these furnaces. The writer has knowl- edge core drying and mold sweating which have been done for the past years with great success, using blast furnace gas exclusively. This study clearly demonstrates that blast fur- nace gas offers attractive field for fuel economy metallurgical furnaces. The Iron Age, November 1930—1289 I l} r the ne ( rs inu ctured Reo Mot ( ( ILS s Mic} plant Mos I the ry ttery + 1] ) tools nN n na manu | h mat ilé i} nning end the build- the motor assembly line } eC eC! Bet eCeT lit ma- hines erne con evol carries cast steel racks ccommodating each. operators from Cranksha RANKSHAFTS are machined ind aSsembDied at the rate 1290—The Iron Age, November 1930 fts for New Reo Cars ATIONS performed the center-drive crank lathe left include rough turn- ing cheeks line bear- and and rough turning fan pulley gear fits. The machine has special turning, beveling, facing, fillet, groov- ing and cut-off tools. Subsequently, No. line bearing ground, shown above cy crank lathe Machined Economically Motor Assembly Line Also Embodies Time and Labor Saving Equipment turning line bearings shown the right. The next operation drilling oil holes the pins, the drilling the holes Nos. and two-spindle drill heing shown below either line can take crankshafts from these racks with little effort. operator needs new piece work, can walk few steps away from his machine rack and secure crankshaft. The con- veyor the endless type, pro- gressing down the crankshaft line the motor assembly line, where backtracks with empty racks the head the crankshaft depart- ment. the first machining operation the cheek No. line bearing rough-turned and finished No. LeBlond automatic lathe. The same work done the cheeks line bearings Nos. double-end crank lathe. There follows series operations all The Iron Age, November 1930—1291 | * drilling and the front and ends of the crank- haft. drilling ma- hines equipped ith riser lock shown thove are used. The view at right shows } the turnover slide ‘ine used turn the motor over frior to passing it 4 Iron Age. November 1930 which are carried out 4AC center-drive crank lathe, equipped wit} number special turning, beveling, fillet, grooving and cut-off tools. The erations include rough-turning and rough-turning the fan pulley and gear rough-turning the flywheel flange and slinger and turning the rear-end shaft tension finished diameter. The stub and flange end are cut off 18-in. American After recentering the ends, the then passes two Nort where line bearings Nos. centered power press. and are ground. From there goes LeBlond automatic lathe, which th: flywheel flange semi-finished, turned and faced, the rear face the flywheel under-cut size, the oil-slinger flange and the bolt head circle are semi-finished, and the oil-slinger and oil-seal grooves are fin- ished size. The face ends No. bear ing also are semi-finished. No. line bearing ground and then Nos. and cheeks are milled for index location, the latter work being performed 24-in. Cincinnati duplex miller. 5AC LeBlond automatic pin lathe used rough-turn and finish the cheeks al! pin bearings. Succeeding Wives ~ clude grinding line bearings, straighten flexible power press, and turning all pin and five line bearings two crank lathes. Quarter-inch oil holes then are drilled the pins battery special two-spindle drilling machines, after which the counterweight seats are milled Cincinnati Hydromatic milling ma- chine equipped with special 36-in. double arbor well special cutters. Two Cincinnati Bickford special three-spindle drills have been installed for drilling and counterboring for counter- weight bolts the cheeks the line bear- ings. All pins and line bearings are ground finish size group Norton grinding machines, and keyway for the fan pulley key milled Cincinnati milling machine. No. Woodruff keyway milled hand mill. The drilling and counterboring the front and rear ends the crankshaft are done two Barnes drills, each which has 17-in. riser block. The clutch pilot bushing hole bored, reamed and centexed, and the flywheel flange faced and cham- fered Warner Swasey turret lathe. Drilling, reaming and countersinking for flywheel bolts are the next operations, after which all bearings and pins are polished Lodge Shipley lathe. Counterweights three spindle have been installed and counterboring holes for counterweight bolts the line bearing cheeks. the left shown the special air fix- ture means which the motor lowered the machine that mills the transmission face the housing The Iron Age, November 1930—1293 i; — b a a 7 3 then are assembled, the crank- shaft put through the final straightening operation, and goes Gisholt precision balancing machi hine tested for balance. screws are place bench and pins and bearings honed. The lutch pilot bushing assembled the shaft Acme arbor press. The crankshaft moves ench with fixture attached for traightening work. After being rigidly inspected, the crankshaft hung the conveyor rack and transported the motor assembly Motor Assembly Line Straight-Line Type LTHOUGH the motor assem- bly line the conven- tional straight-line type found practically all automobile plants, embodies number interest- ing and somewhat unusual fea- tures. The motor carried along 1294—The Iron Age, November 1930 FTER passing through the washer, the motor drained, special device being used raise it. fitting the pis- tons, shown view below, the motor held 45-deg. angle convenient working height, the width the conveyor varying places according whether the motor upright, upside down angle for assembly opera- tions. the line gravity roller conveyor the beginning the assembly line the motor carried roller conveyor through automatic washing machine, where thoroughly cleaned and then through short oven for drying. Line reaming for the camshaft follows, after which the motor picked chain hoist and deposited position for line reaming the crankshaft. Pistons are as- sembled with the motor held deg. angle special rack. this point there slight break the conveyor line and the motor moved few feet short crosswise roller the continu- ation the line. (Concluded page 1361) 7 High-Speed Steel Treated Special Electric Furnace BROOKINGS Metallurgist, Jones Lamson Machine Co. Springfield, Vt. SSENTIAL the heat treatment NIFORM heat treatment large quantities parts, made high-speed steel, necessitates either very strenuous attention the part the furnace operator method timing and tem- perature rally the latter method has proved the most desirable and our efforts toward the development tory heat-treating equipment have been expended that direction. The utilization electric heat appeared attractive because its ease control, quietness, cleanliness, uniformity, and because our power rates are com- paratively reasonable. Also, had hand elec- tric oven type furnace that could used for preheat- ing, and Homo tempering furnace. Therefore, when our gas-fired equipment reached the point where considerable repairing was necessary, decided install electric high-speed steel hardening furnace. Naturally, considerable experimenting and check- ing were necessary before placing the equipment production schedule. However, this installation now working quite satisfactorily, and the present time all the threading chasers for our automatic dies, well taps, lathe tools, and miscellaneous parts, are hardened means this all-electric equip- ment, shown Fig. The loading table, where the parts are placed nickel blocks for heating, shown “A.” This shown more detail Fig. “B” the Westing- house electric furnace used for preheating. American electric high heat furnace shown “C,” from which the parts are quenchd into circulating oil tank “D.” The tempering operation takes plate Homo furnace “E.” each these units consid- erable thought has been given for the maintenance uniform conditions and prevent spoilage work, due failure some part the equipment. high-speed steel parts accurate preheating furnace method timing and temperature con- trol. When the gas-fired equipment the Jones Lamson Machine Co. was found need extensive repairs, was The decided install electric hardening furnace. Details the construction and 1600 deg. Fahr. operation this all-electric equipment Leeds are given this article. “B” has with gas curtain just in- side the door prevent undue scaling the work. maintained about 1550 corder-controller “F” (also seen Fig. equipped with automatic alarm bell. chromel-alumel thermocouple used. The alloy heating unit further protected gold tem- perature limit fuse. The high heat furnace heated vertical Globar elements. The terminals the bars are necessarily water-cooled and continuous water sup- ply assured valvular connections two separate water lines. This furnace also supplied with gas curtain for atmospheric control. The temperature controlled platinum, platinum-rhodium thermo- couple connected Brown controller, shown time clock “H” closes the electrical circuit any predetermined time nightly that the furnace ready for use when the shop opens the following morning. This furnace also provided with second plati- num, platinum-rhodium thermocouple connected Leeds Northrup recorder with range 1500 3000 deg. Fahr. case shown “I.” this in- strument can read more closely than the con- troller, connected red, white, and blue signal lights that are located directly front the oper- ator. Fig. these are barely discernible behind the oil tank “J,” but may more clearly seen Fig. between the two furnaces. Following the usual custom, the blue light indi- cates that the temperature low, the red light too high, and the white light just right. The entire range permissible plus minus deg., the temper- ature used being about 2350 deg. Fahr. more less, depending the nature the work and the steel The Iron Age, November 1930—1295 = 3 7 é ] q q 5 § 5 j A a investigated and used. The two thermocouples are reasonable insur- ance against serious temperature errors. isual variation between the two instruments im- the trouble remedied, Foot Treadles Open the Doors > } rohas ‘ hicrh } ‘ Nar . . Both the preheat and high heat furnaces are pro- vided with foot treadles for opening the doors. hort step and light pressure the operator’s foot iuses either the doors rise. will close its when pressure the treadle removed. When use neither the doors ever losed, better control the gas curtain obtained with opening about in. This opening the preheat furnace obtained placing blocks shelf the furnace under the door shown Figs. and The door stop for the high heat furnace own bolted the floor “A” Fig. the operator releases the foot treadle the door falls, raising the treadle with its cross arm until the otion the cross arm arrested the pin the top and turn halts the downward motion the icing the pin the proper holes the stop. Orig- inally blocks were placed under the door with the preheat furnace, but the continual falling the door apparently caused the cracking some the Globar ements. least, since the shock has been taken the stop the floor instead the furnace frame, breakage has decreased materially. permanent ladder, shown on the side of the furnace, is of much ssistance when adjusting inspecting the Globars terminals. The valves, shown the front the are for adjusting the gas and air used the gas curtains. The circulating oil tank Iron Age. November 1930 The all elec- tric equipment for hardening threading chas- ers speed steel passed through water cooler. The usual oil tem- perature from 110 deg. Fahr. The Homo furnace “E” controlled Leeds cabinet “L.” Excessive temperature indicated red light and alarm bell not shown. standard basket used with this furnace shown the foreground, together with Nichrome cone-shaped screen This cone placed with apex the bottom the basket prevent choking blocking the air and local overheating the charge. hoist the overhead rail facilitates the handling work from the quenching tank and the tempering furnace. Pure Nickel Blocks Used Which Load Parts Parts treated may seen wooden trays Fig. Prior placing the preheating furnace the parts are loaded pure nickel blocks shown. These blocks are made screwing nickel tubing into properly spaced tapped holes rolled nickel strips and forging the upper ends the tubing accom- modate the size the work. These pieces tubing must sufficiently separated that the “shading effect” the parts one another eliminated. Otherwise the end pieces will overheated harder than the others. The tubing serves the double pur pose protecting the heels the chasers from rect exposure the heat and also raises the chasers from the base the block, that the speed heat penetration will not retarded. present are experimenting with blocks cast nickel-chromium heat-resisting alloy effort eliminate the machining and forging operations. these blocks must, course, used High-speed parts heat treated are the trays that the heat-treating time cycle will allow the thor- ough preheating parts any one block. Fig. also shows the tongs for handling the work position around one the blocks and resting upon extension support “A.” The blocks upon slab refractory material while being loaded, that the heat from them will not warp crack the iron table. the preheat furnace two-step secondary hearth has been added, casting which may seen “O” Fig. and also Fig. Placed with the highest step the back the furnace, three steps are provided, including the front part the regular furnace hearth. The nickel blocks with their charges are placed these steps for preheating. increas- ing the height the steps consecutively toward the rear the furnace, the use longer blocks per- mitted and the awkward motion reaching behind the blocks the front for those the rear elimi- nated. This secondary hearth made cast iron, the cost comparatively low and the life quite long. The long life doubtless due part the gas cur- tain which prevents excessive scaling. Special Timing Switch Regulates Hardening From the preheating furnace the blocks are trans- ferred singly the hardening furnace. The ex- posure the heat this furnace accurately timed and this accomplished specially designed tim- ing switch connected electric timing The switch attached the shelf the furnace shown Fig. the operator raises the door and inserts the charge, allows the handles the ‘ tongs rest momentarily upon plate “B.” This weight sufficient depress the plate and its at- tached vertical rod for fraction inch and ro- tate bar “C” upon its axis. the same time, be- cause the connecting levers, the upper end bent lever moves the right and assumes ap- proximately vertical position. hidden pin project ing from the back side forces the diamond shaped fiber piece around upon its axis that the contact blade the opposite end “E” moved downward against contact “G.” Motion bar against its stop pin com pleted means spring “H.” the same time the pin operating “E” moved upward and beyond that spring enabled return contact its horizontal position away from Thus momentary contact has been made between blades and and this contact utilized for closing the starting circuit the timing clock. Timer Adjustable Seconds The timer used shown “B” Fig. and and sec. operated 110-volt synchronous motor and controlled magnetic starting and set- ting strikers. adjusting knob provided for set- ting the time interval desired. Contact between blades and “G,” above men tioned, allows the current operate the starting striker and the indicating hand the clock begins its journey the zero position. The time interval has elapsed when this point reached and alarm bell rings automatically, this being the signal for the oper- The Iron Age, November 1930—1297 7 ro, ator remove the The bell located the Contact the switch blades and (Fig. inside the clock cabinet, above allows the current energize additiona transformer, shown below and the left the clock. net coil connected parallel the regular set-back This second coil magnetically closes the charge removed, the block and tongs striker coil. move ross the furnace shelf under the door switch when energized, that both coils nch the parts the oil tank the left. This gized after the contact the furnace switch blades Liic Walls ill ic ali al . motion causes the block strike against lever broken. The magnetism this second coil also swinging the left from its vertical position attracts iron rod, drawing slowly from the inclined position, shown Fig. Bar loose fitting tube partly filled with thus caused reverse its previous rotation and raise the action may adjusted altering the clearan its former position. the same time between the rod and tube changing the grad x “E” clockwise upon its axis, causing contact specially ing switch con- nected electric timing clock “C” moves downward, rotates fiber oil used. the rod rises, projection the same opens leaf switch the coil circuit, de-ener- against contact “K.” before, spring gizing the coils and allowing the switch open. The mpletes the motion “C” against its stop pin rod slowly falls back into the tube readiness for and spring returns contact “F” its horizontal the next set-back operation. The extra two three sition between and seconds that this delayed action switch keeps the cir- The contact between “F” and “K” utilized cuit closed sufficient return the indicating hand close the circuit momentarily and allow the magnetic the clock any position the dial. striker return the indicating hand the clock back the starting point. The alarm bell also con- Parts Are Quenched Only Oil tinues ring until this has taken place. High-speed steel parts only are quenched the sheet asbestos behind the switch protects oil, after which the nickel block placed the springs and fiber pieces from the radiant heat the loading table, new charge put into the high heat furnace. furnace and the empty block reloaded and placed was found that when the time interval set the preheat furnace. the clock was much taneous contact between the furnace switch blades not Keep the circuit closed time return the indicating hand the clock h longer than minute, the instan- Thus the timing automatically controlled the charging and discharging the work with practi- for sufficient length cally extra motions the part the operator. The entire system timing, signaling and recording starting position. Therefore, “delayed action operated from the 110-volt lighting circuit. switch, shown “C” Fig. was added. 1298—The Iron November 1930 (Concluded page 1360) . J British and Continental Open-Hearth Steel Works—a Comparison WOOD RACTICALLY the whole the output steel Great Britain today made the Siemens- Martin (open-hearth) process. the Continent. the other hand, the Siemens-Martin process has for over years found very strong competitor the basic Bessemer converter, “Thomas” process, generally called. Without doubt this competition between the two leading steel-producing processes has given the fol- lowers each process every incentive improve their practice and performance the greatest possible de- gree. This applies particular the Siemens-Martin process, which, apart from the fact that lends itself better the manufacture very wide range steel qualities and the utilization large quantities scrap, has been susceptible large variations the method working charges, and the design furnaces and the material-handling equipment em- ployed, make more capable competing with the usual lower cost production Thomas steel. Open-hearth furnaces existing Great Britain and Germany, including those installed steel foundries, are shown Table II. This reveals that, small- size furnaces, Germany possesses far greater num- ber than Great Britain, whereas respect units tons capacity and upward the latter shows great numerical superiority. The total furnace tonnage capacity the two countries shows approxi- mately 17,000 tons for Germany and 32,000 for Great Britain. Having regard the fact that the total tonnage steel made the open-hearth process nearly equal the two countries, the great furnace tonnage capacity difference may due part the fact that perhaps greater number furnaces Great Britain than Germany are inoperative (probably per cent), and partly also the greater tonnage obtained per unit Germany. Tilting furnaces installed the two countries number Great Britain and Germany. Outstanding Characteristics Modern Steel Plants Perhaps the most striking characteristic up-to- date open-hearth steel plants the small number furnaces employed obtain large outputs. place long string furnaces being employed yield output of, say, 25,000 tons month, this now often obtained four u