The Iron Age 1937-04-22: Vol 139 Iss 16

Editorial and Executive Offices 239 WEST STREET, NEW YORK, Owned and Published CHILTON COMPANY (Incorporated) Chestnut and S6th Sts., Philadelphia, Pa. 239 West 39th Street, New York, OFFICERS AND DIRECTORS MUSSELMAN, President FRITZ FRANK, Executive Vice-President FREDERIC Vice-President JOSEPH HILDRETH, GEORGE GRIFFITHS, EVERIT TERHUNE, ERNEST HASTINGS, WILLIAM BARBER. Treasurer JOHN BLAIR MOFFETT, Secretary JOHN VAN DEVENTER JULIAN CHASE THOMAS KANE CHARLES BAUR CARROLL BUZBY FRITZ FRANK President J. H. VAN DEVENTER Editor c. E. WRIGHT A. I. FINDLEY Managing Editor Editor Emeritus Machinery Editor Art Editor Metallurgical Editor Associate Editors JURASCHEK Consulting Editor Washington Editors Resident District Editors Pittsburgh Chicago Cleveland Detroit Editorial Correspondents London, England Cincinnati Boston Hamburg, Germany Milwaukee San Francisco SANDERSON ASA ROUNTREE, JR. ALLISON Toronto, Ontario Birmingham Newark, St. Louis Buffalo Contents April 22, 1937 Open-Hearth Operators Birmingham Automotive Methods Applied House Trailers Principles Metallic Corrosion Finishing Vacuum Cleaner Parts New Equipment ....... Steel Earnings 1936 Statistics Metal-Working Activity Rate Activity Capital Goods Plant Expansion and Equipment Buying 108 w w New Industrial Literature Just Between Two Products Advertised 123 Copyright 1937 Chilton Company (Inc.) BAUR, General Advertising Manager DIX, Manager Reader Service Member, Audit Bureau of Circulations ADVERTISING STAFF Emerson Findley, 621 Union Bldg., Cleveland B. L. Herman, Chilton Bidg., Chestnut & 56th Indexed the Industrial Arts Index. Sts., Pa. Hottenstein, 802 Otis Chicage Published every Thursday. Subscrip- Prt at H. E. Leonard, 239 W. 39th St., New York tion Price: United States sessions, Mexico, Cuba, $6.00: Cas- Peirce Lewis, 7310 Woodward Ave., Detroit ada, $8.50; Foreign $12.00 a year. C. H. Ober, 239 W. 39th St., New York Single copy, 25 cents. Cable Address, W. B. Robinson, 428 Park Bidg., Pittsburgh Member Associated Business Papers i 4 - is Bn x 5 1934 the ability bethanized coatings even heavy weights stand severe fab- ricating operations resulted the use bethanized wire for making chain-link fence. Before the development bethanizing heavily zinc-coated wire was available that would stand the weaving operation. The nec- essary heavy coatings cracked and flaked fabrication, greatly reducing their protective value. Consequently had been the practice galvanize the fence after weaving. Beth- anized wire eliminated this difficult opera- tion and also brought superior appearance and lasting qualities this type fence. Years for Bethanize ire 1933 Bethlehem introduced new kind zinc-coated wire with coating applied electricity. This wire, known bethanized wire, had coating different, superior every characteristic that was like new metal. was ductile and tightly bonded the base wire that the most drastic bending and twisting could not cause flake peel. The coating was uniform thickness, providing full protection all points, and was pure (99.99 per cent) practically immune attack even the most sulphur-laden atmosphere. 1935 important manufacturer strand started using bethanized wire his product. Bethanized wire peculiarly suit- able for this purpose because the heavy weight coatings that can carry without damage fabricating, and the high durabil- ity the zinc resulting from its extreme pu- rity. The purity the zinc especially im- portant strand, contamination iron, occurring with coatings applied other methods, opens the door attack acids resulting from sulphur gases the atmos- phere. Strand often used highly-corro- sive, sulphur-laden industrial atmospheres. 1936 bethanized farm fence was placed the market. that time was predicted that this marked the beginning new era fence manufacture, both appearance and lasting qualities bethanized fence set entirely new standards. Recent developments have borne out this forecast, this new fence made instant hit, sales have been limited only production facilities, and trend to- ward electrical coatings has developed the industry. Bethanizing gives farmers the op- portunity obtain super-fence tried-and- proved dependability that good for many extra years service extra cost. These are the high spots the four years that bethanized wire has been made. multitude other uses have been found for this new kind zinc-coated wire, ranging from small springs telephone and telegraph wire, and steadily finding even broader field usefulness. 24—THE IRON AGE, April 22, 1937 THLEHEM STEEL COMPANY THE IRON AGE... APRIL 22, 1937 ESTABLISHED 1855 Vol. 139, No. USINESS seems coming out second best, nowadays, political and labor matters. One reason, perhaps the chief one, that business men have neg- lected mass psychology, whereas politicians and labor leaders have special- ized it. Business men, especially those who supervise the running industrial organiza- tions, have neglected mass psychology because they have been busy doing other things. First, they have had acquire extensive knowledge the technical aspects their businesses. Then they have had equally difficult task mastering the intricate principles marketing. After that, they have the truly Gargantuan task coming through period with something left the treasury. The politician and the labor leader not need spend their time acquiring this information and for that reason can give their time the science Gas-Tro- nomics. This special division mass psychology which consists the tech- nique making the greatest number people swallow what the politician the labor leader has offer the moment. Chloroform not used the operation inducing people swallow what plain common sense should tell them not good for them. But three powerful gasses are used and the methods using them and timing them constitute the chief bag tricks the politician and the labor leader. Hence the term Gas-Tronomics. The first gas the hope gas. This makes people believe that everything will all presidents private concerns knew much about using this gas politicians, they could keep their companies red for seven eight years stretch and still get the enthusiastic endorsement their stockholders. The wise politician always keeps either depression recovery around the When things look bad, it's time for the hope gas. When they look good, the fear gas comes into play. much for politicians. Labor leaders also are expert the use these two gasses, but they and some politicians too use third gas much more deadly effect. known the hate gas and the people who breathe swallow will carry scars for the rest their lives. ) ) ) Open-Heart ASSEMBLING for the first time the deep tional open-hearth con- ference Birmingham, Ala., was more conspicuous success than officers the American Institute Mining and Metallurgical En- gineers had anticipated. Over 200 members made the long trip south April and total registration was about 270, which betters the previous record 258, established the 1936 meeting Detroit. addition the registration for the open hearth sessions, additional 175 engineers gathered the same time hear and present papers be- fore the Blast Furnace and Raw Materials Committee. This was the first time the open-hearth and blast furnace groups had met for paral- lel sessions since 1927. All technical discussions both groups were held ballrooms the Hotel Tutwiler, Birmingham, Wednesday and Thursday, April and The open-hearth operators confined their discussions refrac- tories, furnace construction, quality and metallurgical problems, and extended session general prac- tice technique; the blast furnace group was mostly concerned with raw materials, construction and operation blast furnaces, and the use iron and slag. Both groups, about 450 475 altogether. devoted Friday, April all- day inspection trip the mining and steel-making properties the Tennessee Coal, Iron and Railroad Co. the business meeting the com- mittee voted hold next year’s meeting the Hotel Statler, Buf- falo, Y., the week April 17. Opening the initial session the open hearth meeting Wednesday morning with few words greeting, Tranter, general chairman, pointed out that fuel ef- ficiencies, refractories, insulation, furnace control, furnace construc- tion, safety, quality control, and raw materials all are subjects which 26—THE AGE, April 22, 1937 Tis not the king’s stamp can make the metal better.” * * IRMINGHAM welcomes Wednesday foremost scientists metal. the great valley Lord has flanked with coal and iron and floored with limestone there assemble today tives nearly all the impor- tant iron and steel companies North America. They are here for joint session the twen- tieth national open vention and the blast furnace and raw material division the American Institute Mining and Metallurgical Engineers. Among them the institute’s president, Mr. Allen. him and all who accompany him Birming- ham offers the salute city whose very existence com- ment upon the science they serve. * * * Within radius few miles from the Tutwiler where these gentlemen assemble are billions tons iron ore and more billions coal. the removal those tons years come bring maximum benefit those by, for and among whom they are sci- ence must superintend more faithfully each year. Econom- science, social science, phys- ical * The several hundred thousand here who are not metal- lurgists can offer nothing the tinguished visitors will engage. But can point them with hos- pitality and pride our city, the special favors Providence be- Spring, the pool stars its night lights make from the rim architecture and landscape im- posed upon glories hill tree, civic-mindedness that makes hospitable special measure the science that created and keeps alive. ** Anent his Franklin Roosevelt loves Southern agriculture but has heartbeats for Southern in- dustry, President Scott Operators Swap should discussed, and pre- dicted that many worthwhile ideas would developed. this country the entire steel industry state flux, and many new ideas are being proposed; and, Mr. Tran- ter said that open hearth men must try not either reactionary ultra-conservative.The open hearth process has certain inherent defects, and operators must not blind them- selves them. known that heat transfer the open hearth should be; consequently different method heat application the development greater heat resist- ing roof brick may the answer. The present method casting steel into ingots most certainly not the ultimate nor all that can de- sired, according Mr. Tranter. Since the advent hot and cold strip mills with the resultant pour- ing large slab ingots, becomes more and more clear that sooner later another method pouring should devised eliminate ex- cessive segregation the top such ingots. also stated that several plants are working method direct pouring steel between water cooled rolls. Many operating difficulties must solv- ed, however, before such scheme becomes practical. High-Magnesia-Ferrite-Bonded Refractory Following the opening remarks Mr. Tranter, the session re- fractories was initiated lengthy discourse hearth refrac- tories for steel making William McCaughey, Ohio State Uni- versity. stated that attempt- ing prepare magnesia refrac- tory bonded with calcium ferrite, difficulty was encountered ob- taining suitable source mag- nesite which would contain only small amount silica the cal- cined product. The silica requires added the refractory convert the magnesium silicate (serpen- tine) into dicalcium silicate before 4 | : any ferrite bond developed. The necessity adding lb. lime neutralize lb. silica before de- veloping the ferrite bond made desirable seek source pure magnesite its equivalent. Mr. McCaughey continued stating that was thought possible beneficiate the dolomites northwestern Ohio removing most the lime. Since these dolomites contain only very amounts silica, this would fur- nish suitable supply pure mag- nesia. During the development such process, deposit bru- cite (magnesium hydroxide) was found Nevada. The brucite Nevada occurs massive deposits and remarkably free from silice- ous impurities, the impurities are such coarse fragments that they are easily removed the min- ing operation. The availability such deposit high magnesia, low silica mineral made desirable use such mineral deposit be- fore magnesia separation process based dolomite was completely reduced commercial practice. Brucite, when calcined, yields mag- nesium oxide which particularly suitable for the commercial devel- opment calcium ferrite bonded magnesia refractory. The manufacture calcium ferrite clinker, continued Mr. Caughey, calls not only for low- silica source magnesia, but also for careful proportioning the lime with respect the silica and iron oxide, and careful furnace control insure the formation ferrite. With careful control raw materials and firing, calcium-fer- rite-bonded-high tory was made, aproximately the following composition: 2.5; 7.0; 1.0; 10.0; and MgO, 79.5. The calcium ferrite developed this refractory produces hard, dense, refractory granules having bulk density 125 135 per cu. ft., and true specific gravity about 3.6. Birmingham Earl Smith Chief Metallurgist Republic Steel Corp. described his recent tour foreign steel- making plants, the Wednesday, April open-hearth and blast furnace operators, Hotel Tutwiler, Birmingham, Ala. * MR. SMITH SAID: steel mills have made them- selves practically independent outside scrap supplies through the use basic bessemer converters and open hearths. instances they use 100 per cent mill scrap. Scrap from the basic bessemers (about per cent) goes into low-grade open hearth, which turn feeds its scrap into high-grade open hearth, the scrap from which turn fed into very high grade electric furnaces. Thus, single plant will have four types melting and refining units and will making everything from low- grade plain steels the highest quality alloy material. all prob- ability, the stringency American scrap continues, steel makers here will adopt similar furnaces Corby, England, are using per cent ore 0.2 0.8 per cent sulphur, and are desulphurizing the ladle and basic mixers with soda ash, hydrogen and steam (the quantity soda ash equals about per cent the iron). plant Saarbriicken, Germany, uses liquid soda ash for the same purpose, and drops sulphur from 0.08 0.04. The English iron made the soda ash process very high grade, and, with equivalent labor cost about 40c. per hr., the pro- less certain steel makers are turning out plain and alloy steel about equiva- lent the best the United States. Next year they probably will the world's second largest ° ° LIPPERT Metallurgical Editor, THe ° ° tory consists about per cent periclase, per cent calcium fer- rite, and per cent calcium silicate, according Mr. McCaughey. furnace temperature, the calcium ferrite fluxes part the calcium silicate, producing some per cent bond. Sufficient calcium ferrite formed rapidly set the refrac- tory the furnace. However, the amount both calcium ferrite and calcium silicate maintained low possible order avoid re- fractory dilution. Magnesia kept maximum amount periclase which gives permanence the re- fractory and resistance iron-rich slags. The high density the refrac- tory and the the re- fractory coalesce, produces dense monolithic hearth high magnesia content having max- imum resistance iron-rich slags, which necessary with low car- bon steels. Based these principles, car- load this high-magnesia, cal- cium-ferrite-bonded refractory was manufactured and trial under- taken 150-ton furnace one the large steel companies. Objec- tions the part the melter using this new refractory, Thom- asite, without slag admixture had overcome. However, Mr. Mc- Caughey, stated that remove the prejudice the melter against ap- plying the refractory without slag, two test samples were run the breast the furnace top raw dolomite, one with slag, and the other without slag. Thesample without slag knitted together form solid cake over the mound raw dolomite. One the rods used for shaking down heat was placed over the refractory and, when the refractory was pulled out the furnace afterwards, clear impression the rod was seen the solid refractory cake. After this demonstration, the melter used the material recommended and THE IRON AGE, April 22, 1937—27 — | | “See ge — without slag admixture. The cal- cium-ferrite-bonded magnesite was used over period days the one furnace with satisfactory re- sults. During the test, Mr. McCaughey continued, bad hole developed one the adjacent furnaces. This hole was such large proportions that ordinarily magnesite would have been used for patching and considerable time spent putting the patch. the suggestion the melter, this hole was repaired with several layers the new material, and patching was accom- plished short order. The patch was very satisfactory and with- stood regular furnace operation during the week that the trials were run. Mr. McCaughey said that or- der distinguish from other basic refractories, the high mag- nesia-ferrite-bonded refractory has been given the name Thomasite honor the man who developed both the basic open hearth process and also the refractories that made possible. New Inland Furnaces Following the discussion re- fractories, description was given Co.’s new open-hearth furnaces. stated that January, 1936, the Inland Steel Co. decided proceed with the construction four new open-hearth furnaces, built line with the present furnace shop. These furnaces, which are now operation, are 150-ton eapacity each. The overall dimen- sion outside the brick work ft. in., this length being limited the decision hold the same building design the old shop. This meant that these 150-ton fur- naces had built into bays which were ft. center center, the same the old 125-ton fur- naces, which turn had been originally designed for 80-ton fur- naces. order provide hearth capacity, checker capacity and suf- ficient size uptakes and give due consideration brick economy from the standpoint gas veloci- ties the furnace system, every bit available space had made use and some interesting departures from struction were necessary. obtain the desired capacity and hold with- the limiting overall length, 33- in. depth bath was required. The hearth ft. wide and ft. long inside brick foreplate level, 28—THE IRON AGE, April 22, 1937 making total 623 sq. ft., area 4.15 sq. ft. per ton steel produced. Mr. Hutchinson continued stating that the bottom consists in. dead burnt magnesite taphole, in. plastic chrome, insulating brick, in. Therm- o-flake concrete. Side walls are first quality firebrick and chrome brick covered with plastic chrome. The firebrick battered from in. 13% in. the foreplate, and faced with 9-in. chrome brick laid headers take care ex- pansion. Plastic chrome in. the bottom and battered in. the foreplate, front The front wall above the foreplate consists wall battered in. the skew, the top in. being silica brick with chrome brick below. The sloping covered with in. firebrick and in. chrome brick all laid headers. The furnace roof in. silica brick with 22% in. thickness ft. out from the backwall. There are two 18-in. rib courses, one over each end door. The distance from foreplate skewback exactly ft. The rise the roof arch in. Roof insulation consists in. Therm-o-flake granules covered with coating. The insulation put after the fur- The uptakes have combined area sq. ft., and the throat area the bridge wall sq. ft. The front end panel constructed 22% in. bonded chrome; the back end panel in. Metal- kase. The regenerator roof flat suspended arch 12-in. brick in- sulated in. granules, cov- ered with in. insulating ce- ment. The neck arches are also suspended and lead suspended nose arch the Simplex interlock- ing type the slag pocket end. Regenerator roof construction first quality firebrick, while the neck arches and nose are super quality firebrick. The throat be- tween slag pocket and checkers ft. in. length. Sides flare from ft. in. the slag pocket ft. in. the checkers. The opening the top the bridge wall into the checkers ft. in. sq. ft. area. This type con- struction provides slow even flow gases with good distribution heat the regenerators. The checker chambers are ft. length. Checkers themselves are the Loftus type with heating surface 26,780 sq. ft., which equivalent 178 sq. ft. area per ton hearth capacity. The checker openings are in. sq. all direc- tions. The height from the floor the top the checkers ft. in. The depth checkers varies from ft. in. the flue en- trance ft. in. the bridge wall. The walls are firebrick 22% in. thick backed with in. insulating brick which laid insulated coating. The floor tonsists in. firebrick laid in. insulating brick. Thermocouples are set the front bulkheads the basement floor level. Mr. Hutchinson continued his de- scription the Inland furnaces stating that the furnaces are equip- ped with waste heat boilers the horizontal fire tube type In- land’s own design. There super- heater ahead the boiler. The boilers are rated 20,000 lb. steam per hr. 210 lb. pressure. in- duced draft fan set the end the boiler with rating 45,000 cu. ft. per min. driven 125 hp., 750 r.p.m., a.c. motor. Dampers are all Blaw-Knox wa- ter cooled. The stack 165 ft. high, ft. inside diameter and lined with 6-in. blocks. Oil Gas Fuel The fuel these furnaces oil oil and coke-oven gas. Tar can also used. Oil atomized steam from the boiler superheaters. Individual furnace oil heaters, us- ing steam the heating agent, keep the oil constant tempera- ture. This temperature thermo- statically controlled, and thermo- meter indicates the oil temperature the operating panel. positive displacement oil meter and re- corder shows the total oil consump- tion and indicator the panel shows the instantaneous rate gal. per hr. The flow oil set micrometer valves. the fuel lines each end the furnaces are motor operated valves protect- water cooled jacket. These are controlled switch the instrument panel. Closing the valve for furnace reversal breaks the circuit controlling the induced draft, leaving louvres open which ~ allows the other valve opened quickly. Furnace reversals are controlled electrically master switch. the present time, none these furnaces has completed campaign, the oldest which has 415 heats addition the bottom. therefore not possible give any results draw any very def- inite conclusions ultimate performance, except that furnace operation date has been very satisfactory. 415 heats the only ‘ PER CENT = 1932 YEAR gredients were mixed cold con- crete mixer and rammed for the full thickness the furnace. Mr. Scott stated that the first cold bot- tom was made per cent screened magnesite and per cent bonding material, the latter be- ing made cold setting plastic chrome cement, tar, and other in- gredients. Later, the bonding mate- rial was changed per cent cate (just enough make the magnesite plastic). What other hearths brought forth discussion. Grim the Hep- penstall Co. stated that the eco- nomic use natural gas open hearth depends local plant conditions. His experience with na- tural gas was limited low pres- sure applications with natural draft, and stated that the dif- ficulty with low pressure natural gas getting high flame tem- perature with the proper lumi- nosity. The accepted use fans © AVERAGE OF ALL PLANTS BY PLANTS, AVERAGE OF ALL PLANTS Br TOMMAGE CAPACITY residual metals the open hearth since 1929. Although there some change from year year, there significant trend line for any the important metals. brick repairs have been the front wall. Mr. Hutchinson concluded stating that the oil consumption per each furnace gal. per ton steel which tapped with bath analysis 0.05 per cent car- bon. Quick Bottom Several the steel companies ravaged floods during the past year had interesting experiences putting new open-hearth toms with minimum loss time after flood waters though one superintendent reported burning new bottom 126 hours, the attention the meeting Scott, Sheffield Steel Corp., who mentioned putting cold bottom and having ready for all- scrap charge hr. The thinnest section this cold bottom was in. near the tap hole, ranging in. the thickest section. The bottom in- ingredients were the new bond- ing material, any, Mr. Scott re- fused disclose despite numerous leading questions open-hearth men attendance. This bottom has operated for many months (526 heats) heats varying from ingot iron (0.02 0.100 and far the plant has experienced less trouble than usual- arises for conventional hot-set bottom. Mr. Scott mentioned that furnace within hr. rather than hr., such speed absolutely necessary. Several operators, however, were the opinion that unwise put bottom quickly. Their contention was that inasmuch bottom stays for years, slow burning new bottom will the long run show greater efficiency and require less attention. Natural Gas Open Hearths Several queries regarding the use natural gas for firing open open-hearth furnaces should allow for increased heat transfer checkers. This fuel being clean, smaller checker openings should practical and the increased benefits higher air preheat capitalized. Mr. Grim continued stating that the cost the gas Pitts- burgh compared with low sulphur fuel oil b.t.u. basis favor- able, but the oil furnace usually makes better time. Natural gas has lots advantages over oil, such storage, piping system, need for atomizer, lack need preheating, etc., but the time element usually the reason for using fuel oil. The type port used with gas depends upon the operator. There are innumerable designs and all are the best. Most them accom- plish the same thing and all them must shaped and sized give the proper velocity and direction the flame. Most gas furnaces have hipped roofs roofs with valleys. The type roof con- THE IRON AGE, April 22, 1937—29 1933 934 1935 1036 1937 struction somewhat dependent the port construction. The con- struction the port the crux the furnace operation using low pressure natural gas. The areas checker fantail, uptakes, and port must kept proper pro- portions and limits which one works are very narrow. Following Mr. Grim’s comments, George Coughlin, the Ash- land division Armco, stated that natural gas throughout the country ranges heating value from 1000 12,000 B.t.u. depending the field being used. Also, these same gases range specific gravity from 0.6 0.68. Because these variations, the different gases must handled differently, according local conditions. Compared the amount air necessary burn the gas, very small volume gas used. And because its constituents, can- not preheated, which would course increase its volume and would thus make easier direct into the furnace. However, get the greatest value from natural gas heat necessary crack the gas and get what might called diffusion particles throughout the fuel-air mixer that these dif- fused particles may become incan- descent from the burning products combustion and transmit radi- ant heat from the fuel itself. Mr. Coughlin believed this best can done means low-velocity injection the natural gas into the entrance part the furnace, which hot enough crack the gas. Also, this point the pre- heated air for combustion can pick the fuel and carry across the bath. Such type flame more necessary course when the bath has its blanket slag, which really acts heat insulator and through which necessary transmit heat the metal. Because this comparatively low velocity the air-gas mixture, extremely difficult control the flame direction, which very desirable order keep away from the roof for the full passage across the hearth. Because this control difficulty necessary extremely particular the de- sign the port floors and roof smooth flowing eddy-less streamlined flame. After the discussion the use 30—THE IRON AGE, April 22, 1937 natural gas metallurgical fur- naces, talk was given Ralph Sweetser, blast furnace consult- ant, the effect carbon pig iron, with particular emphasis the idea that combined carbon the controlling factor iron qual- ity. Mr. Sweetser stated that from review limited number analyses pig iron made sand pig beds and graded eye; from study the analyses recent machine cast foundry iron graded analysis and further classified fracture; and from recent re- view the analyses steel mak- ing iron made during extensive temperature tests has been brought the belief that the per- centage combined carbon pig iron the analysis which can safely used indicator its present char- acter, its past environment and its future behavior. continued stating that much evidence now available support the theory that the decid- ing factor determining whether certain pig iron will make good open-hearth steel, not high total carbon very low sulphur, but low combined carbon the pig iron. considerable amount actual operating data was put the record Mr. Sweetser sup- port his theory. Residual Metals The usual report residual metals open-hearth steels was again prepared this year John Sullivan Battelle Memorial Institute. Mr. Sims the institute, presented the data the convention. stated that this day in- creasing use alloy steels, there belief that some this alloying material will soon finding its way back into the open hearth unwanted amounts. far, how- ever, Battelle has found such indication, and examination the graph Fig. indicates that metals should anticipated the near future. The current report for 1936 cov- ered detailed analyses samples taken from plants with annual capacity approximately 8,500,000 tons. comparing the detailed analyses for last year, evident that there have been marked changes the amount residual metal except manganese, which not true residual metal because intentionally added the pig iron furnish heat with predetermined manganese content. the case some in- dividual plants, the percentage residual metals changed, but whereas the change was upward one plant was downward an- other. Therefore, the average changed but little. The average all plants ton- nage capacity for the various residual metals 1936 were fol- lows: nickel, 0.042 per cent; cop- per, 0.103 per cent; tin, 0.013 per cent; manganese, 0.18 per cent; chromium, 0.029 per cent. graph showing the variation all the metals since 1929 reproduced Fig. Several operators private con- versation were the opinion that these data residual metals might not entirely representative for the reason that too great per- centage the data may have come from plants using great deal hot pig iron. Sodium Fluoride The consensus regarding the ef- fect sodium fluoride additions molds was decidedly favor its use, although the beneficial results are not great. Republic reported its use for many years; De- Corp., reported its successful application for three years; and Tietig, Jr., Andrews Steel Co. gave some detailed data his use the material over the past few months. All users agreed that the proper addition sodium fluoride rim- ming steel ingots about oz. per ton for the lower carbon grades and oz. per ton for the higher carbon steels. The sodium fluoride metal has been poured the mold form cushion. The action mechanical rather than chemical, attested the roaring sound and the strong sodium flame dis- cernible. all probability all the compound burns out the steel. All three men stated that when ingot followed through the rolling and finishing stages, difficult discern any difference between steel treated not treated with sodium fluoride. was con- ceded, however, that surface ap- pearance might show slight im- provement. Also, the ingot treated 4 with sodium fluoride requires some- what less chipping. The value sodium fluoride comes from the violent momentary mechanical action created the bottom the ingot the time when most needed. low- rimming steels the action very much increased. Probably its value more pronounced ingots large cross-section (30 in.), and also those higher carbon rimming steels (0.20 0.25 C), that the range carbon which most difficult rim. Mr. Tietig stated that low- Ratio Sulphur Slag Sulphur Metal removing sulphur. The higher the iron oxide the slag, the high- the oxygen content the bath, other factors being equal. According Mr. Chipmana number methods have been used the past for describing the basicity open hearth slag. Usual- for any one given practice, sufficient have the ratio measure how basic the slag is. But when various prac- tices are compared, when data from several shops are used studying the effects slag composition, found that the comparison more trustworthy Ratio Bases Acids Slag 2—These data illustrate the marked superiority highly basic slag desulphurizer. 0.08 the metal came fast and then immediately dropped and kept dropping the metal rimmed across. Mr. DeVaney stated def- initely that primary blow holes were moved from the surface, and that the holes were smaller and much cleaner when sodium fluoride was used. There was not much change segregation, any. Basicity Slag subject dealt with consider- able detail during the Thursday morning session was the effect slag composition upon oxygen, car- bon, and sulphur the bath. Some comments this general question were introduced John Chipman the American Rolling Mill Co. Mr. Chipman pointed out that well known, course, that car- bon, oxygen, and sulphur the bath are affected the composi- tion the slag. The more basic the slag, the more effective will the ratio total base total acid the slag used. The important basic oxides are CaO and MnO. The basic char- acteristics FeO are weak com- parison with these, and most the MgO open-hearth slag not really solution but dispersed grains periclase. The im- portant acid oxides are SiO, and The other acid oxides, and are probably somewhat weaker their acidic properties, and, account complete lack knowledge their chemical behavior, they are reluctantly omit- ted from consideration. Mr. Chipman continued stat- ing that the effectiveness the slag removing sulphur from the bath dependent upon many fac- tors, such the composition and fluidity the slag, temperature, area bath, and amount action that occurs. The great importance slag basicity illustrated Fig. measure the de- sulphurizing power the slag, the ratio sulphur the slag sul- phur the metal tap used. these studies both slag and metal sulphurs were determined the evolution method. Occasional comparisons with gravimetric sul- phurs show fairly good agree- ment. Although there consider- able scatter individual points the plot, Mr. Chipman’s data whole indicated the mark- superiority the highly basic slags desulphurizers, and the average represented the heavy line (see Fig. may taken the norm the basis which should possible study the effects some the other variables. Basic Open-Hearth The session slag basicity was followed long résumé basic open-hearth iron, prepared Paul McKimm, Otis Steel Co. Mr. absence, his data Granite City Steel Co. was stated that one question which comes more often than any other that deoxidation, i.e., whether add spiegel, silico- spiegel, silico manganese, manga- nese the bath and on. Mr. McKimm believes this depends solely individual plant practice, each has its specific usefulness under certain conditions. His ex- perience has been that when the residual manganese normal, slag satisfactory and heat well shaped up, box pig iron should added for reboil and manganese should added the furnace, part the furnace with final addition the ladle, all the ladle. test for one year was con- ducted where half all heats had manganese addition, part the furnace and the balance the ladle, and the other half all heats with total manganese re- quirements made the ladle. difference could determined any respect. This being true, the manganese should then saved, according Mr. McKimm. stated also that special deoxidizers have their benefits mostly steel higher carbon and those that are killed, but, they are not re- quired for low carbon rimmed steel unless individual plant practice would such that some definite benefits could derived. (CONTINUED PAGE 58) THE IRON AGE, April 22, 1937—31 Ag oh Ris + + + + + - + + + + + + + OD + + + : Q | ] ° | * One the new models Bender all steel trailers. utomotive Methods THE house trailer has adopted the production and assembly methods the automotive in- dustry trailer plant just placed operation the Bender Body Co., Cleveland, for the manufacture new line all steel trailers designated the Bender travel mansions. particular interest the iron and steel industry the fact that the Bender company has thrown aside the hesitancy that the trailer industry has shown to- wards the use steel the manu- facture trailer body frames and side walls. The new Bender trail- all steel construction, has all steel frame and the outer cover- ing the body also entirely steel, that all members that give the body its strength, rigidity and durability are formed steel mem- bers which are joined riveting and welding. The use wood confined mostly cabinets and other interior equipment. 32—THE IRON AGE, April 22, 1937 trailer field, heretofore appar- ently undeveloped and offering wide possibilities, the construction what designated commercial shells, production which has been started the Bender plant. The shells without any the in- terior equipment required for house trailer may fitted for nu- merous uses such carrying salesman’s stocks and samples and the demonstration merchandise and appliances. The interiors these may fitted meet the customer’s requirements. Incident- ally, addition transformer, which regular equipment for converting city current six volts for lighting, outlets are provided the 110-volt circuit for electric appliances and power generator furnished with one model special equipment which may supply cur- rent for demonstrating electrical appliances. School busses will also added the Bender line equipment. These, all steel, will made production basis standard models. objection that has been made the all steel trailer that uncomfortably hot summer. With complete insulation and air pockets between the insulation and walls and ceiling, the Bender trail- ers are built for both summer and winter use, the insulation keeping out the summer heat and winter cold, the interior the larger models being kept warm winter stove burning charcoal, wood, coal, briquettes. pioneer motor coach body construction which has been engaged since 1919 and the de- velopment the all metal coach body, the Bender company de- ciding enter the trailer field ac- quired for its trailer factory the four-story Willys-Overland plant Elyria that had been idle sev- eral years and four months com- pletely equipped with the most modern facilities for trailer manu- facturing. The plant has over 4 é — 450,000 sq. ft. floor space, being, claimed, far the largest plant the country devoted exclu- sively the manufacture trail- ers. With extensive system conveying equipment for handling parts and for assembling, the plant laid out for economical routing and moving work process and final assembly. The layout for the progressive production and assembly was developed Howard Dayton, production engineer the company. There are five lines overhead tramrail aggregating 2200 ft. length that are used the fabri- cation sub assemblies and for moving these the point which final assembly starts and five chain type power driven conveyors just House Trai above the floors, approximately 1620 ft. long with synchronized speeds which trailers are kept trailers are shown moving down one the as- sembly lines for the addition various parts. moving during assembling opera- tions. Equipment provided for definite production schedule trailers 8-hr. day, which means that one trailer will leave the assembly line every minutes. The chassis rails are sheet steel and the cross members and outriggers are 14-gage ma- terial, all channel sections. The chassis parts are set jigs and arc welded, the welds being made all the way round the joint pro- vide strength and rigidity. Spring sockets and the “hitch” are hot riveted the chassis. The chassis then moves along its tramrail line point where the wood floor laid the chassis. Then the monorail carries into spray booth where the completed chassis ers sprayed all over with chassis enamel. building the sides the posts uprights, cross members and other parts that form the right and left sides are assembled jigs and are welded. Then the steel panels, which are 20-gage cold rolled steel, are attached, being fastened place with quick working screws. The uprights and cross members are 18-gage channels and angles. After attaching the panels the sides are suspended the tram- rail and carried upright po- sition jigs which the sides are riveted their supporting members. assembling the tops, the roof members, consisting posts, roof bows and channels are are welded jig and carried along the line the next station where wood furring put in. The next step PRENTISS ° ° ° putting the deck, which plywood deaden sounds and im- prove the radio reception. THE IRON AGE, April 22, 1937—33 ~ 2 a % Tae | the 4 : | 4 A 34—THE IRON AGE, April 22, 1937 the front and back assem- bly lines with the panels place. UILDING the chassis for trailer bodies. The members are set jigs and arc welded. the two production lines for fabricating the front and back frames. The second line directly back the columns. — start the final assembly line. The chassis mov- ing few feet from this point picked the power con- veyor. chassis moves along the monorail line from the lower end this room the point the fore- ground where the floors are put and then into the spray booth where coating chassis enamel applied. ECTION the press room which trailer parts are formed. Many the presses had not been installed when this picture was taken. When com- pletely equipped this department will have power presses. THE IRON AGE, April 22, 1937—35 he Sy vty “Ss, - 4 ie : lation and wiring follows, after which Masonite inside lining applied the top. Fronts and backs are assembled adjoining building, being constructed angles, channels and bars that are clamped jigs and welded. Moving along the monorail line the next station the panels are welded and riveted place. After riveting the fronts and backs are metal finished. The various sub assemblies dur- ing their fabrication move their respective tramrails towards one central point which they reach completion. That point the head the first the line floor conveyors for final assembling and other succeeding operations. The first these power driven lines the body assembly line, the next two are paint lines for the priming and finishing coats, the next the furniture assembly line and the fifth the final inspection line. soon the employees are properly trained for their work and regular lished, operations the assembly conveyors will performed while the work moving along the lines. The first step assembling placing the chassis dollies which they move along the con- veyor. Then the sides and next the fronts and backs are taken from the tramrail and set place and the sub assemblies are all bolted, riveted and welded together. After these are joined the roof put and bolted position. the body moves along the line metal finishers put joint moldings and the in- terior sprayed with dust pre- 36—THE IRON AGE, April 22, 1937 ventive and rust resisting cement for the adhesion Sealpack water- proof insulation which then ap- plied. The metal window panels, drip moldings and some other parts are installed after which alum- inumlastic canvass roof deck put place and roof ventilator installed. Window regulators are then put and the window glass set. The next operation lining the interior with Masonite and steel. About per cent this surface, including curved portions and sec- tions under the windows, sheet steel. Metal finishing the entire body inside and out follows. Going the paint lines after assembling the bodies are spray coated with synthetic primer coat and move through oven which they are baked 225 deg. Then they pass into color spray booth which three coats lacquer are applied. After painting the body moved the furniture assembly line where the furniture, stoves and other equipment are installed. the end this line the body picked eletric crane and the axles, springs and wheels are installed and the brakes are hooped up, after which the trailer run onto testing machine and tested for rattles. From this goes the final inspection line and while moving along this line the finish, both inside and out, checked. moving off this line the trailer ready for storage and shipment. Each production line has store stockroom which stored handy the points which they are used all supplies such screws, hinges, etc., that are re- ations. trim shop for making uphol- stery for the trailers located the fourth floor. this mattresses and cushions are manufactured. The third floor used for mill and cabinet assembling room. The wooden cabinets, cupboards, ward- robes, etc., after assembling, are chain power conveyor which takes picture shows sulation and wiring into the tops, which are then hung the monorail and moved the assembly floor. ° ° them through spray booth for the priming paint coat; then through drying oven, sanding room, through another booth where colors are sprayed and then through second drying oven. Moving out this they are masked and third spray booth for the final From here they the opposite side the room catches, locks, etc., are assembled. The wooden interior equipment then trucked the final assembly floor. The completeness these new house trailers indicated the compactly arranged equipment that provided for the comfort the occupants. This includes daven- port and dinette seats that open into full sized double beds with drawers beneath, gasoline cook stove, heating stove, 20-gal. water tank with pump, cupboards and cabinets, utility combination cabinet and wardrobe, including shower room, chemical toilet and full length mirror. hot water tank and heater for shower baths furnished extra equipment. 4: the operating characteristics the various types motors are known (see The Iron Age, April 15, page 40) the prob- lem selecting the right motor for any drive one analyzing load elements, and starting and control require- ments. ELECTRIC motors are rated terms horse- power, taking into con- sideration both torque and speed elements. Torque ex- pressed terms pound-feet available turn shaft. not power energy. electrical prac- tice used designate the force pounds producing rotation- effect upon shaft distance one foot from the center the shaft. shaft-twisting effort lbs. measured the end imaginary lever arm projecting inches from the shaft center Speed expressed terms the number revolutions per minute the shaft. Complete motor specifications electing Motor Fit Drive ° ° ° FRANCIS JURASCHEK Consulting Editor ° ° listed most motor manufactur- er’s catalogues will contain three figures for each motor, under the heading “Torque pounds foot radius”; torque full speed, starting torque with full voltage, and maximum running torque. times, however, brief specifications, starting torque and torque will expressed centages the full-load torque, and unless the full-load torque specifically given pounds foot radius, will necessary ascertain this from the motor man- ufacturer make adequate analysis drive situation. Most motors develop their maxi- mum running torque from two- thirds three-fourths full speed. Likewise the voltage the current supplied the motor has distinct influence the actual maximum starting torques which that motor can develop. appears quite common prac- tice carry voltage the power house substation per cent per cent above the normal volt- age for which the motors are rated, insure that the drop may not too far below normal for effective use motors far removed from the plant source power. This has the effect boosting maximum and starting torques the first motors the line approximately proportion the square the percentage the voltage may in- creased above normal, with figures correspondingly less for voltage below normal. These conditions are frequently adjusted, however, the installation transformers, laying out the current distribu- tion system the plant secure approximately normal voltages each motor. Sometimes the frequency al- ternating current will vary (as cycles per second instead 60). Motor speeds are directly af- fected such variation; that is, motor speeds will less more than rating the same percent- ages that frequencies vary under above normal. Since the horsepower ratings motors are based full load torque full speed, all such varia- tions torque and speed will affect the actual horsepower delivered the motor. All standard general purpose motors (except fractional horsepower sizes) are built today with service factor per cent permissible overload. This indi- cated many motor nameplates the standardized phrase adopted the National Electric Manufac- turers Association, “Service factor THE IRON AGE, April 22, 1937—37 3 3 S - : | Ay 4 4 | 1.15 rated volts and This service factor multiplier which, applied the normal horsepower rating, indicates the permissible loading within the accepted safe limits temperature rise for the insulation used the motor. (All guarantees efficiency, power fac- tor, etc., however, are based the normal rating the motor, and not apply the rating obtained using the service factor.) For example, for maximum load hp., hp. motor may used, since 1.15, 57.4 horsepower indicated the permissible loading; provided the starting and maximum torques the hp. motor are sufficient, and the volt- age and frequency are maintained. Determination Motor Size The power demand machine drive the ordinary measure the size motor required. For any machine drive which re- quires definite torque, more pow- speed than low. determining the power demand necessary consider the normal speed opera- tion, and also the starting torque and maximum torque demands. analysis the elements any loa