The Iron Age 1933-09-14: Vol 132 Iss 11

THE IRON September 14, 1933 J. H. VAN DEVENTER G. L. LACHER Ww. W. MACON T. H. GERKEN R. E. MILLER Editor Managing Editor Consulting HBditor News Editor Machinery Editor WINTERS Jk. BURNHAM FINNEY GERARD FRAZAR Detroit Boston Cleveland Chicago Editor Emeritus Washington Cincinnati CONTENTS Challenge National Leadership Steel Farm Structures Reduce Fire Losses Beer Boosting Steel Barrel Business Uses Induction Type Ovens for Enameling OUR PART Paint Destroys Metal Coating Welding Technique for Nickel-Rich Alloys Metal Forms for Floor Become Ceiling Personals and 48-F Automotive Industry 48-G Construction and Equipment Buying and Products Advertised Index Advertisers 106 safety THE IRON AGE PUBLISHING COMPANY Ask PUBLICATION OFFICE: Corner Chestnut and 56th Sts., Philadelphia, Pa. Cut EXECUTIVE OFFICES: 239 West 39th New York, Y., motor Member, Audit Bureau Circulations ADVERTISING STAFF trol and A. K. Hottenstein, 802 Otis Bidg., Chicago Published every Thursday. Subscription Price: Peirce Lewis, 7338 Woodward Ave., Detroit United States and Possessions, Mexico, Cuba, $6.00; Charles Lundberg, Kent Rd., Upper Darby. Canada, $8.50, including duty; Foreign, $12.00 Del. ; . year. Single Copy 25 Cents c. H. Ober, 239 West 39th St., New York Wis. Robinson, 428 Park Pittsburgh > W. C. Sweetser, 239 West 39th St., New York Cable Address, ‘‘Ironage, N. Y."’ D. C. Warren, P. O. Box 81, Hartford, Conn. SEVENTY-NINTH YEAR SERVICE THE METAL WORKING INDUSTRY = 1 Philadey hia under ‘ * =, i, | 4 aw? ree ‘ 3 2 ‘= aS THE 14, 1933 Page MAN CORROSION never sleeps, never takes vacation. Every hour the day and night he’s the job, grimly devouring every- thing can lay his greedy hands on. The property destroys each year totals millions dollars. Chain him up, and little expense, using low-cost, rust-resisting sheets Beth-Cu-Loy. series long-time tests carried out the American Society for Testing Materials, sheets copper-bearing steel (Beth-Cu-Loy composition) proved first resistance at- mospheric corrosion among the entire range commercial steels and irons. Yet Beth-Cu-Loy Sheets are low cost. They are, fact, inexpensive that often they can used place ordinary steel sheets with only negligible difference material costs. Used installations around your plant, Beth-Cu-Loy Sheets mean added durability and less upkeep. Used your products, Beth-Cu-Loy Sheets give you, little cost, the potent sales appeal rust-resistance. Bethlehem Steel Company, General Offices: Bethlehem, Pa. oor IRON AGE.. SEPTEMBER 14, 1933 ESTABLISHED 1855 Vol. 132, No. alk Action? Challenge National Leadership output, which rose from low per cent the third week March per cent July, has declined with further recession cent loss per cent activity the past few weeks not only erases all the gains purchasing power the per cent steel code wage rise, but reduces below where was when the Blue Eagle drive began. evidently the matter. suspect that first-class recovery rv that real action superseded talk. time that the doctors cease experi- convalescing patient. day may need the leadership those who wish reorganize society. But today our prime need the kind lead- ership which will get the wheels the recov- ery engine started and keep them going after they are started. time reorganize the crew. labor are far less impor- tant than the right the American peo- ple deliverance from the depression. UCH deliverance can come only the assertion fearless and resolute leader- ship our President—the type leader- ship that will put stop selfish efforts obtain private advantage out great na- tional undertaking, the type leadership that brought out the banking crisis, the type leadership that will cut through the mountains words piled visionaries and opportunists and arrive practical, attainable objectives. : ever and ons | ange ; that 2 | | | = < u-Loy sales Stee a What metallurgists are asked give specific answer the question— What alloy steel?—the re- sults are surprisingly variance. And they are asked whether given steel the alloy class, lack agreement equally pronounced. Several the technical societies have attempted establish defini- tion, and committees have been ap- pointed and questionnaires have been circulated. Thus far nothing definite has materialized. result conversations with metallurgical friends, but not with the expectation that the matter could settled, canvass was made the following manner: lurgical authorities, letter was sent asking for statement “just what constitutes alloy steel” to- gether with definition alloy steel distinguished from plain car- bon steels. Accompanying this was list selected ranges certain steels concerning which there has been, is, some difference opinion, with request for “Yes” “No” reply whether they are the alloy steel class. the accompanying table giv- ing the result the replies, the steels selected are found. The vanadium and molybdenum types were selected because, one time least, there were some who insisted that, unless these similar elements were present excess 0.50 per cent, they could not classed alloy steels. There has always been difference opinion the high sulphur and phosphorus steels. The replies show that there unanimity opinion the vana- dium and molybdenum and similar low-content alloy steels, but that only very few regard the high sulphur and phosphorus types the alloy class. The greatest difference opinion prevails regarding the low-copper steels (0.20 0.25 per cent Cu) and the high sulphur and phosphorus types. Men whose opinion the met- allurgical world highly regarded are among the few who not re- gard the copper steels the alloy class but place the high sulphur and phosphorus that class. Alloy Stee! EDWIN CONE One metallurgist styles the low-cop- per (0.20 0.25 per cent) well the high sulphur steels “special classes carbon steel.” Another opinion the ef- fect that “we not consider high- sulphur high-phosphorus steel alloy steel these are metalloids and not true alloying elements. That is, they not actually alloy them- selves with the steel but remain the steel foreign material non-metallic state.” Another reply sulphur and phosphorus are not metallic elements, and the word alloy connotes two more me- tallic elements, some other term should coined for these.” Another authority states that “in view the fact that the high-sulphur high-phosphorus steels are possibly for the intent improving certain physical characteristics they might considered alloy steels.” inter- esting testimony runs follows: should not call steel contain- ing the 0.10 0.15 per cent sulphur alloy steel because the free-cutting properties are definitely mechanical ones and not metallurgical ones, addition which sulphur one the ordinary impurities included definition. If, Carpenter’s case, addition selenium, or, some other cases, addition tellurium made with the same object, should certainly call the products alloy steels because neither tellurium nor selenium conventional constituent. steels with phosphorus additions the same remarks apply sulphur. The Medium Manganese Steels Regarding the so-called manganese” steels find the follow- ing remarks: would not consider steel with 1.00 1.25 per cent manganese alloy steel. Hundreds thousands tons steel rails and other steel prod- ucts have been made the past, par- ticularly, the Bessemer process, containing regularly from 1.00 1.25 per cent manganese and were never considered alloy steels. Incident- ally, this rail steel contained usually 0.10 0.12 per cent sulphur. barrel steel with manganese range 1.30 per cent manganese has never been considered alloy steel. inclined the opinion that only steel containing excess 1.25 per cent manganese should classed manganese alloy steel. 14—The Iron Age, September 14, 1933 Manganese over 1.00 per cent cer- tainly modifies the properties plain carbon steel and would come under the alloy class, says another com- mentator, while another states that enormous majority steel producers would express the opinion that (medium-managanese steel) belongs the alloy class. The Low-Copper Steels considerable variation opinions found regarding the copper steels. One reply is: “The question copper rather more involved, because cop- per very usual incidental impurity steel, though seldom exceeds 0.10 per cent. copper were added with the definite metallurgical object in- creasing corrosion resistance, should tempted call even 0.25 per cent copper steel alloy steel but admit that the extreme border line.” From two prominent metallurgists comes the comment: “The reason why would register our opinion classifying (0.20 0.25 per cent Cu) non-alloy steel that that amount copper may introduced into steel through the use scrap and would seem that, practically, alloy steels such compositions con- tain alloys the unavoidable quan- tities resulting from the use scrap the manufacture the steel. Thus, for example, although nickel steel clearly alloy steel, one would prob- ably not classify 0.25 per cent nickel steel alloy steel because the fact that this amount nickel may normally contained carbon steel coming from alloy mills.” From another reliable source comes this testimony: “As not believe that has been definitely shown that 0.25 per cent copper results defi- nite improvement either physical chemical properties, should not list 0.25 per cent copper steels alloy steels. With more than 0.50 per cent copper, should list them alloy steels.” adds this interesting com- ment: “Steels containing more than 0.06 per cent vanadium, more than 0.10 per cent molybdenum, more than per cent manganese, more than 0.30 per cent chromium, more than 0.50 per cent nickel, more than 0.20 per cent tungsten, more than 0.25 per ?—Survey cer go! the ste defi | as pr | ve co st | to eit tu mer the silic der cop) stee hav phe ting ity loy stee com nevi pho: side Teas Says allo only ting not ‘allo the not into and Some Suggestions ain der om- ngs cent aluminum, more than 0.80 per cent silicon, and more than 0.20 per cent titanium would come the cate- gory alloy steels, opinion.” From these few excerpts, plain that difficult secure unanimity whether certain steels are alloy steels. This demonstration the need definite clarification the subject. Varying Definitions Alloy Steels not possible analyze here all the various definitions which have been proffered. few them will reproduced with some the com- ments. One the best and most definite is: alloy steel may considered one that, through the addition metallic elements other present plain carbon steel, very considerable increase the me- tallic elements, silicon and manganese, commonly present plain carbon steel, possesses marked difference physical characteristics, mechanical, electric, magnetic, etc., resistance atmospheric chemical action, either normal elevated tempera- tures, from plain carbon steel. This definition assumes that the ele- ments plain carbon steel are only the following: Carbon, manganese, silicon, sulphur and phosphorus. Un- der it, steel with 0.20 0.50 per cent copper might classed alloy steel provided can considered having marked resistance atmos- pheric action corrosion. Free-cut- ting high-sulphur steels, this author- ity holds, can hardly classed al- loy steels, and even now, plain carbon steels with equivalent sulphur are common general purpose steels and hever considered anything other than plain carbon steels. High-phos- phorus sheet steel can hardly con- sidered alloy steel for the same adds. “My own attitude this matter,” well known authority, “is that, strictly speaking, definition alloy steel can made because steel itself alloy some five six elements. Therefore becomes case only defining describing set- ting some arbitrary limits for analy- which common consent would considered ‘ordinary steels.’ ‘alloy steel,’ believe have con- Sider the question intent. When the ordinary limits are raised un- Usual amounts even when elements regularly present commercial steels are added, then believe get Vote Metallurgical Authorities Classifying Steels Alloy Group and Otherwise Type Per Cent Molybdenum ............... 0.20 0.50 plus Manganese— (Medium manganese) .1.00 (or 1.25) 1.75 High sulphur— (Free cutting) ...... High phosphorus— (For sheets) ...... Yes Doubtful Vote ing university offers this: Alloy steels are steels some the distinctive properties which are sub- stantially altered the presence one more elements other than car- bon. This authority, however, does not classify copper (0.20 0.25 per cent) high-sulphur high-phosphorus steels alloy steels. Other definitions briefly are lows: Alloy steel deoxidized steel which substantial quantity an- other metal has been added modify its useful characteristics (Suggested minimums; 1.0 per cent for mangan- ese, tungsten, aluminum; 0.50 per cent for silicon, nickel, chromium; 0.20 per cent for copper, molybdenum; 0.10 per cent for vanadium. Alloy steel alloy iron and carbon containing least 0.10 per cent silicon and also containing suffi- cient amount additional element produce improvement the physical chemical properties the article made the steel. alloy steel one which ele- ments besides iron, carbon, sulphur and phosphorus are present suffi- cient amount make marked dif- ference the physical properties the metal. Alloy steels are steels which one more special elements have been added modify the properties or- dinary carbon steels. Any steel alloy steel which contains any element intentionally ad- ded for the improvement proper- ties (except for the purpose merely making the steel sound, such the normal additions manganese and silicon). into the field alloy steels.” Alloy steels are those which the added elements are not put for soundness but for action altering the properties and produc- ing results over and above what can gotten from plain carbon steel. alloy steel steel which some alloying element has been added for the purpose conferring some advantageous and appreciable change one more physical chemical properties. for alloy steel other than steel carrying sufficient amount alloy that the properties the steel are noticeably affected the alloy con- tent—the word “properties” referring any physical characteristic the steel which may affected. Interesting comment from another metallurgist the effect that: Copper, vanadium, molybdenum present the extent 0.15 per cent more, manganese 1.00 per cent more; phosphorus 0.06 per cent more; sulphur 0.06 per cent nickel, tungsten, and/or chrom- ium 0.25 per cent more would either singly con.vination with each other affect the properties alloy steel. becomes clear, therefore, that any the alloy ingredients, present individually above the amounts given, would class steel alloy steel. If, however, num- ber these elements present were present quantities slightly less than the percentages given above, they could easily enough have combined, effect equivalent some one element present quantities more than the percentage indicated above, and there- fore again such steel would classable alloy steel. Further brief comments some the authors the definitions repro- duced are follows: “For the purpose duty the tariff laws set arbitrary limits beyond which (Concluded Page 70) The Iron Age, September 14, 1933—15 7 4 7 te - els. 0.1 with ould per ‘ why cent hat uced crap > con- juan- prob- cent . that cal alloy cent alloy than than 0.50 per FTER nearly quarter century experience meet- ing the needs farms, the James Mfg. Co., Fort Atkinson, Wis., started serious way the develop- ment steel farm structures. Ex- periments, now completed, have been under way for several years that now this company offering com- plete line steel farm structures. engineers and sells struc- tures. The Republic Steel Corpn. furnishes the metal the James’ blue prints. The de- cision fabricate farm structures Ohio rather than Wisconsin was reached because was believed un- economical haul steel Wisconsin and then back haul the fabricated parts the most densely populated part the country which lies east the Mississippi River. Ohio well located with respect the cen- ter population and because the metal produced Ohio its fabrica- tion the steel mill’s doorstep ap- ptars logical. The metal used iron alloy which has been specially developed Republic accordance with the prac- tical experience gained James meeting the farmers’ All structural members, tubing and sheets are made from this iron. Gal- vanizing used where experience dic- tates. The United States Department Iron Age, September 14, 1933 HIS alloy iron struc- ture (at left) pre- fabricated and its erec- tion the field matter ordinary tools and class labor that readily available. Steel Can Agriculture estimates that the value all farm structures and their con- tents about $23,000,000,000. The buildings alone are worth $11,000,- 000,000. There are 37,000,000 build- ings all kinds the 6,000,000 farms this country. Annual re- placement calls for 150,000 barns, 188,640 poultry houses, 62,880 hog houses, 50,300 milk houses, 37,720 im- plement sheds, 25,140 silos, 86,020 corn cribs and 138,336 dwellings. The lumber tonnage for year’s replace- ment 3,284,192. All these struc- tures can made steel. Requirements for steel structure first that must give better and longer service than the farmer has had from other designs and materi- als. Its cost must comparable that replacing the old structure with one the same general design and materials. Finally the fabricated parts must such easily and economically erected the av- erage class labor available farm areas. The James company called signer who understands framework design for single fabricated steel part heavier than stick lumber that would ordi- narily into similar frame struc- ture. For instance, roof trusses and columns for steel barn are built light weight channel sections and the chords are made square bars bent Save the proper angles the ends and welded the channels. Wooden strips, treated resist fire, are bolted between the channel legs used nailing strips for attachment in- sulating materials and steel sheath- { a These steel barns are designed without hay mow thereby q 7 = Lt} inner and outer shells (at right) the “kutcrop keeper” place. Hay stored the ventilated section formed the two shells which dre attached the rings. the minimum and making them more wind resistant. 300,000,000 Year ing. typical design consists structure consists actually four ROGERS FISKE steel frame insulated inside and out- shells, telescoped together. The inner THE side. Metal sheathing covers the in- shell built solidly flanged estern Editor, side and outside the walls and the sheets and stored corn. The ceiling. The roof may com- next shell, also made sheets, position material. Mastic seals all spaced few inches from the inner joints not otherwise tight. shell order provide air space. This second shell formed pro- Wind-Resistant Structures vide series openings for ventila- The question can raised tion the hay. The third shell the effectiveness light member steel like the second but nailed nail- framing high winds. These struc- ing-strip channels that are supported tures have been tested for pressure the outer flanged sheet steel shell. resulting from wind velocity Hay stored the ventilated space Further, has defi- between the second and third shells. hay loft need not The steel for storing hay. cattle barn need only low struc- Viewing this entire development ture that will provide workable head once appreciated that all these room space within. There another steel farm structures are actually de- way handling hay storage. There- signed units and may as- fore, what danger may result from sembled give structures al- spontaneous combustion completely most any size and arrangement removed from the barn and the cat- desired. tle. The latter many cases have Steel construction the logical an- resulted from special breeding the following farm losses that not replaced any cost. older designs and materials. Origin The patented steel structure used blaze unknown, $70,000,000; for hay storage built the gen- taneous ignition, $30,000,000; light- eral form cylindrical silo. Cir- ning, $12,000,000; wind storm, $40,- cular channels, fitted with nailing 000,000, and deterioration, $240,000,- ized sheets which form the shell. The for the products steel mills which sheet flanges are bolted together and should add many tons annually or- the joints filled with mastic. The der books. The Iron Age, September 14, 1933—17 4 2 4 | ~ a Beer Boosting Steel Barrel Business months research the Murray Corpn. America, Detroit, recently began the manufac- ture insulated steel beer barrel the external appearance which like the old-fashioned wooden barrel. Production increased rapidly and today stands 5000 barrels day. This new activity, resulting from the revival the brewing industry, providing employment for about 1000 men and requires approxi- mately 180 tons sheet steel daily. estimated that two out three beer barrels made the present time are steel, whereas pre-prohibition days all barrels were constructed wood. The Murray barrel, weighing per cent lighter than wooden barrel. RUNNERS formed (above) the surface the outer shell fit standard conveyor systems, protect the bung from damage handling and reinforce the barrel sides against “bead,” expanding operation, shown this photograph barrel (at right) consists inner and outer shell 14-gage sheet steel with insulating material the dead air spaces between the shells. The insulation insures the maintenance beer the proper tem- perature winter summer, the same wooden barrel. The steel shells are graph showing the second drawing operation the fabrication the outer shell. This operation performed 450-ton double- action toggle press requiring skilled operators. 18—The Iron Age, September 14, 1933 rough handling. The formation the runner, ELDING (at left) the The bung adapted standard cleaning, filling equipment, During its manufacture the barrel goes through number welding operations which give For the welding work the Murray Corpn. has installed large amount new weld- ing equipment the latest type. : s r / i the The ipted cleaning, pitching During hrough welding hich give strength. ling work large weld- the ype. exterior and interior barrels (above) are rust-proofed being Bonderized. This process said not only prevent rusting, but also make the inner surface the barrel porous that pitch will adhere tightly it. BARRELS pass through spray, booth (at right) overhead conveyor and receive coat enamel. They then are carried through overhead baking oven which the enamel well baked the surface the barrels. SSEMBLY (above) the outer and shells are shown the floor). The inner shell formed from two half sections steel welded to- gether. The smooth inner surface the barrel with well- rounded corners in- sures cleanliness. The Iron Age, September 14, 1933—19 | Regenerator Chambers for natural gas-fired open-hearth furnaces that requires special at- tention the regenerative chambers. second feature the design The object the regenerators open-hearth furnace preheat the air for combustion. higher preheat will result higher flame temperature, faster working furnace, and lower fuel consumption per ton steel produced. Therefore, designing furnaces converting fur- naces for the use natural gas, any improvement that will increase the temperature preheat should given careful consideration. The fac- tors that affect the temperature preheat open-hearth are fol- lows: Temperature the products combustion; Design regener- ative chambers and checker work; Amount air preheated. Temperature Products Combustion fast working furnace the waste gases leave the hearth temperature 3000 deg. The sensible heat these gases this point equal per cent the total heat input into the furnace, and desirable that these gases conducted through the downtakes and slag pocket the regenerator with possible. The heat loss along this path due radiation and infiltra- tion cold air. The loss due radiation may reduced insu- lating the slag pockets and regener- ator chambers. The loss due the infiltration cold air may elimi- nated encasing the ends, downtakes, slag pockets, and regen- erators the furnace insulated sheet steel casing, covering these parts the furnace with insulating cement tar. The infiltration cold air this point dilutes the waste gases and this reduces their temperature. re- cent test (*) this drop temperature was found 400 deg. The temperature waste gases the hearth was 3000 deg. and the temperature entrance regener- ator was 2600 deg. this tem- perature were increased would pro- duce corresponding increase the temperature the preheated air. may seem like going lot expense encase parts the fur- nace steel plates, but should William Henry. 20—The Iron Age, 14, 1933 7 remembered that open-hearth fur- nace cannot made permanently tight the application slurries the brick work alone. Therefore, the heat loss radiation reduced and the infiltration cold air prevented, the waste gases from the hearth the furnace will reach the checker-brick with the minimum loss temperature. This the first stop toward the efficient operation regenerators. The design any regenerator chamber compromise between that which will produce the maximum heat transfer, and that which will remain open the passage gas throughout the campaign the fur- nace. For example, very small stag- gered openings between the checker- brick will produce the maximum heat transfer between the waste gases and the air, but these small openings would quickly clogged the particles slag brought down from the bath with the products com- bustion. The principal constituents this deposit the checkers are limestone, cinder, and silica. There certain 7,000 Cc ° 5,000 9 Qa Volume Checkerwork, Cubic Feet follows: Brick thickness, in. .......... Air velocity, ft./sec. ......... Maximum Rate Fuel Consumption Millions per Hour Approximate Corresponding Furnace Sizes Fig. 2—For given tonnage rating furnace, the curves show the volume checker work required for specific flues and brick sizes, Valve Heatin 50ton oe — 7o FO Of I | p YA bi 2,000 sing Natural Gas will gas fur- ecker- heat and enings the from com- this ertain WILLIAMS Industrial Gas Engineer Equitable Gas Co., Pittsburgh amount this deposit produced non-combustibles the fuels. Since natural gas clean fuel and does not produce any ash, the checkers natural gas-fired furnace remain open longer, thus increasing the num- ber heats the campaign. Fur- thermore, the volume the products combustion are less natural gas-fired furnace, which results the gases carrying over less dirt from the hearth. These with the instal- lation pusher fans for supplying air, have enabled the designer natural gas-fired furnaces reduce the size the openings between the checker-brick, thus increasing heat transfer and reducing the fuel con- sumption per ton steel produced. the past has been the custom compare regenerators the basis feet brick per ton fur- nace capacity, pounds brick per ton alone. These figures varied wide ranges, one survey show- ing range 130 cu. ft. brick work per ton furnace capacity. When comparisons are made this basis alone, they are very mislead- ing because they fail take into con- sideration the efficiency utilization the checker-brick. The following factors must all considered when comparing and work: Method laying brick; size and type brick; size vertical flues; volume checker-work. Laying Regenerator Bricks Checker-brick should laid the and air passages are vertical. The waste gas should pass downward through the checker-work and the air being heated should pass upward. There less channeling with this type construction than there checker arrangement having horizontal flues. There are three common methods laying checker-brick with vertical flues. They are, namely, solid chim- ney checkers, standard checkers, and checkers with variable cross section flue. does not seem make much difference which these ar- rangements used far heat transfer concerned. However, the standard method, Fig. most pop- ular produces solid checker- work with minimum amount brick. Size and Type Brick the past the most popular sized calculate the sizes regenerators for open-hearth furnaces using natural gas the central feature this article, which the third series de- voted points design peculiar the natural gas application. The author takes occasion incidentally urge special precautions mini- mize air infiltration, the use steel jacketing. The first article covering the broad economics the general subject appeared Aug. 24; the second, focusing ports, was published Aug. 31. The next instalment will take combustion control. this brick still used more than any other size. However, there trend the present time toward thinner in. This trend especially no- ticeable the small and medium sized open-hearths. This change taking place because the rate heat transfer within brick slow that any part the brick more than in. from the sur- faces has practically value for Fig. 1—This sketch checker work, built in. thickness brick form in. sq. flues, typical the most popular method laying the brick. the storage heat during 15-min. cycle. other words, the thinner the checker-brick the higher its heat storage capacity compared the volume occupies, and the greater will the amount heating sur- face for given weight brickwork. However, the in. brick should still used large furnaces be- cause the period between reversals longer, and the volume the regen- erator large that large brick are necessary increase the strength and insure the stability the check- er-work. There also trend the present time toward the use high-alumina silica brick for the top courses the regenerator. These brick are more refractory than ordinary fire brick and consequently they should, greater degree, withstand the high temperatures the top the regen- erator and ingrease the life the checker-work. Vertical Flues Checker Work The area the vertical flues should made small possible order secure the maximum heat transfer, and large enough prevent clogging. These flues were usually about in. square, but they are now being reduced many natural gas- fired basic furnaces in. square, and some gas-fired acid furnaces in. square. The heating sur- face regenerator may in- creased per cent replacing brick and reducing the flues from in. square in. square. The total area all the flues regen- erator should sufficient permit the flow the air required for com- bustion the velocities the regenerator. using natural draft, the velocity the air through theregenerator should to3 ft. per sec. the furnace equipped with fan for forcing the air into the re- generator, the velocity through the The Iron Age, September 14, 1933—21 = | | | 1 ! is ae WAL) checker-work may ft. per sec. Volume Checker-work The volume checker-work re- quired for open-hearth furnace dependent upon many variable fac- tors. However, the curves shown Fig. were developed assuming values for some the factors and varying the others between the limits usually found practice. The fol- lowing conditions apply all the curves Fig. (a) Temperature waste gases top regenerator, deg. 2600 (b) Temperature ofwaste gasesat bottom regenerator, deg. 1325 (c) Temperature air bottom regenerator, deg. F....... 500 regenerator, deg. F...... 2000 min. reversals. Standard arrangement checker brick, Fig. per cent excess air. (h) infiltration cold air. The ordinate the graph gives the volume checker-work one side the furnace only, which the length the width the regener- ator the depth the checker- brick. The abscissa gives the maxi- mum rate fuel consumption, with supplementary scale showing the approximate corresponding furnace sizes, Curve No. based in. square flues, which are recommended for small acid furnaces fired nat- ural gas. blower should used secure the air velocity mentioned. Curve No. based in. square flues. This arrangement checkers has been tried number acid and basic furnaces and has been found entirely satisfactory. recommended for all except large .furnaces where thicker brick are needed because their strength and stability. Curve No. based in. square flues, in. brick thickness, and ft. per sec. average air veloc- ity. This air velocity that usually reached when operating the furnace natural draft. Curves Nos. and are based in. square flues. This the most common checker large steel mill furnaces. The average velocity air through the checker work was taken ft. per sec. for natural draft and ft. per sec. for furnaces equipped with pusher fan for blowing air into the furnace. average air tempera- ture 1250 deg. was used cal- culating the above air velocities. important recognize the re- lationship that exists between the vol- ume checker-work, velocity flow, and depth checkers. The free area the regenerator determined the velocity flow desired. The ra- tios flue area total cross-sec- tional area are follows: Flue Areas in. sq. flues, in. brick thickness, 34.0 per cent in. sq. flues, in. brick thickness 41.4 per cent in. sq. flues, in. brick thickness, 32.7 per cent 22—The Iron Age, September 14, 1933 The volume checker-work divided the cross-sectional area the re- generator gives the depth checkers required. This calculation trated the following example: Consider furnace approximately tons capacity, with maximum rate fuel consumption 33,000,000 B.t.u. per hour; standard checker work, Fuel natural gas with gross heat content 1130 B.t.u. cu. ft. (a) Equip- ped with blower; (b) natural draft. determine depth checker-work and num- ber brick required: 33,000,000 1130 29,200 cu. ft./hr. maximum rate gas consumption 29,200 3600 8.1 cu. ft./sec. maximum rate gas consumption Since cu. ft. gas requires 10.7 cu. ft. air for perfect combustion, and are allowing for per cent excess air: 8.1 10.7 1.05 cu. ft./sec. Air required the average air tem- perature 1250 deg. 9 91x 300 cu. ft./sec. 60 + 460 (a) the furnace equipped with Flue area required 300 (ft./sec.) tt. Since for in. flues and in. brick the ratio flue area total area 0.414, the total cross-sectional area the re- generator 0.414 145 sq. ft. Referring Fig. curve No. the volume checker-work required for the furnace 2260 cu. ft. 2260 145 15.6 ft. depth checkers required. (b) the furnace operated na- tural draft: Flue area required 300 (ft./ sec.) 120 sq. ft. Total cross-sectional area the regen- erator 120 0.414 290 sq. ft. Referring Fig. curve No. the volume the checker-work required for the furnace 2900 cu. ft. 2900 290 ft. depth check- ers required. The number brick required can determined from the following table which gives the number brick per cubic foot volume checker- work. 7.1 brick/cu. ft. 3.5 brick/cu. ft. part (a) the preceding example, the volume checker work was 2260 cu. ft. Therefore, one regenerator will re- quire 2260 6.1 13,800 checker-brick. part (b) one regenerator will re- quire 2900 6.1 17,700 brick. The curves shown Fig. are based the heating surface required for heat transfer. The theory under- lying this method designing regen- erators found Trinks “Industrial Vol. pages 152-169. increase the heating capacity re- generator either because the size heats has been increased, higher degree preheat desired. There are number ways which this problem can handled. They are: Thinner checker-brick and smaller flue openings may The checker-work may made deeper. case the regenerator cannot made deeper because reaching the water level for some other reason, two-pass regenerator may built. building two-pass regenerator the waste gases should flow down- ward both passes. Checker-brick may placed the flue between the regenerator and the reversing valve. This would result having horizontal flues this tion the regenerator. all the above methods in- creasing the heating capacity the regenerator involve increasing the draft loss through the regenerator, probably will advisable install fan the furnace for forcing air into the regenerator under pressure. Amount Air Preheated this article have already mentioned the importance bring- ing the waste gases the regenera- tor with the minimum heat loss and have also brought out the import- ance proper regenerator design. order secure the maximum tem- perature preheated air neces- sary make sure that all the air necessary for combustion going through the regenerators and being preheated. idea the magni- tude the infiltration cold air into the furnace may secured again referring Mr. Henry’s article “Thermal Study Open-Hearth Furnace.” Mr. Henry found that only per cent the air required for combustion passed through the incom- ing generator, while there was 9.9 per cent excess air the waste gases en- tering the regenerator, and 22.5 per cent excess air the waste gases leaving the regenerator. This test il- lustrates the large infiltration cold air occurring open-hearth fur- naces. Preventing Infiltration Cold Air This infiltration cold air into the preheated air can prevented making the brick work the furnace tight possible. Enclosing the regenerators and passages plate insulating cement, and in- stalling pusher fan the furnace order maintain pressure the incoming side and hearth all times also very essential. This problem similar the one mentioned the first part the article. that case the cold air was diluting and cooling the products combustion; this case the cold diluting and cooling the preheated air. Reduce the infiltration cold air and both problems are partially solved. Other reasons for installing blower open-hearth furnace discussed the next article this series under the title “Open-Hearth Combustion Control.” Plyr | | yy | and Cor ler due expr teri bak The the tem hole mak the ing hea cha: are the The Air the the steel the times one the was cts air heated cold rtially ing will this Jearth Plymouth radiator shells, conveyor chain, entering the new induction type enameling oven. enamel radiator shells has been reduced per cent and the quality the finish improved the plant the Plymouth Motor Corpn., Detroit, division the Chrys- ler Corpn., the installation in- duction type ovens. The maintenance expense for these ovens surprising- small, for there little any de- terioration equipment and mate- time required for baking The principle used pass enameled steel parts which are baked through the center series electrically charged wire coils. The secondary current passes through the radiator shell and thus the enamel baked even temperature. Since the paint dried from the inside the outside, leaves firm, dense film free from holes wrinkles. the modified “A” type which makes air seal, greatly improving the thermal efficiency and the work- conditions either end, the ovens the conventional tunnel wall material with over- head chain conveyor running through carrying the load. The conveyor bronze and the rails aluminum. Two kinds side walls are used; one oven has hollow metal Panels packed with insulation and the other constructed fibre board. They give equally good service. Inductor coils consist No. cop- per wire wound solenoid through which the load hanging the conveyor must pass. Coils are not continuous throughout the oven, but are broken make use three-phase connection and pro- duce the greatest heat the end the oven where the work enters. Be- ing large section copper, the coils themselves generate little heat. They are supported ordinary insulators much the same manner that open wire work handled. thin wall inside the coils protects them from mechanical damage case material conveyor hook should come loose. The bottom the oven has smooth finished surface. Heating the steel parts going through the oven not radiation from the coils across large air space, but the effect the mag- netic field produced the coils flow- ing the parts. The parts thus are ama originating the metal sheet and passing outward through its coating enamel, frees the surface from holes wrinkles and cuts enameling time. This reversal the customary application heat from without made possible the use induction type ovens. Plymouth Uses The Iron Age, September 14, 1933—23 Induction Type Ovens Bake Enamel Steel Parts BAILEY Electrical Engineer, Chrysler Corpn. dried heat generated them- selves. The temperature rises rapid- that required for baking, after which the part passes into weaker field where the power input the part balances the radiation and holds the temperature constant. The result that the parts are maintained than the air surrounding them, with only small power input, thereby accomplishing major economy. The walls the ovens carry off only small amount heat, the difference temperature between the air inside and outside the ovens not nearly great with ordi- nary hot air circulation methods heating. The air discharged from the ovens low velocity. The dis- charge point the top center, con- sequently there leakage fumes heat from the ends the ovens where the operators stand. The speed the conveyor and the power voltage are variable over wide limits, giving sufficient flexibility take care changing production conditions. Power, 360 cycles, three-phase, 250 volts, furnished motor generator set. The power factor the ovens low and correc- tion made means static con- densers. When the volume work being carried through the ovens light, the amount electric power used (Concluded Page 70) being earth or per il- cold fur Reaction With Paint Destroys Metal Coating Waldorf-Astoria Tower ANY reports have been circu- lated regarding the cause the discolorations the east- ern the two towers surmounting the new Waldorf-Astoria Hotel New York. has been widely stated that the towers are sheathed with stainless steel and that the material one them proved defective and has deteriorated, probably because its being exposed inaccessible loca- tions, where cannot wiped off intervals. This impression has been strengthened because metallurgist company producing stainless steel once made the state- ment before technical society that such steel would tarnish and rust, due the soot, dirt and sulphur gases city’s atmosphere, unless “its face could washed now and then.” has also been reported that, being stainless steel, the tower the east- ern, ocean, side had rusted because the effect trade winds. All such reports are without foundation. The two towers, one which shown the accompanying illustra- tion, are made copper. The origi- nal intention, according the archi- tects, was treat them with acids order give them the green coating, patina, which time results from exposure the weather. Instead, was decided cover them with alumi- num. This was done two different processes. The copper the western tower was first painted with gray paint over which the aluminum foil sheets were placed. The eastern tower was painted with red lead which the aluminum was also placed. time the reaction between the lead paint and the aluminum the eastern tower gradually destroyed the aluminum, exposing the red paint. Thus this tower gradually losing its dress aluminum with the re- sulting appearance rust. The western tower seems remain originally treated. Welding Locomotive Frames HILE welding locomotive frames fairly well standard- ized, new problems calling for modi- fied technique are continually arising. One these problems was recently encountered Eastern railroad frame pedestal jaw. The section the break had already been welded and had broken near the weld. The supervisor decided that the metal adjacent the break was fatigued condition and required re- moval. Therefore the pedestal was cut away and forged filler piece was prepared fill the gap. This was joined double oxy-acetylene weld and the entire section was then built give added strength. The total cross-section the repaired pedestal ay against the original Fig. shows two operators work simul- taneously completing the weld and building the section. Fig. shows one operator putting finishing touches the completed job. The total weld- ing time was 10% hr. and consump- tion gas was 3300 cu. ft. oxy- gen and 3000 cu. ft. acetylene; 125 lb. vanadium steel welding rod was used. The welding apparatus was made the Air Reduction Sales Co., New York. Fig. two operators work simultaneously completing the Fig. 2—Shows one operator putting finishing touches the com- weld and building the section 24—The Iron Age, September 14, 1933 pleted job ) whe ere a Ww ro In ar flu ra har the - Fig. simul- and shows touches weld- oxy- ne; 125 rod was us was Co., ELDING nickel and nickel al- loys was discussed length Herbert Herrmann the Metallurgist Supplement The En- gineer, London, April 28. This contribution large part was fol- lows: Pure Acetylene commercial acetylene frequently contains sulphur, pure gas must expressly specified. does not suf- fice employ “practically” pure gas. Only absolutely sulphur-free acety- lene should used the welding nickel and its alloys, since even traces sulphur (as low 0.005 per cent) will render the weld brittle. The same applies all the other welding ma- terials employed, including welding rods and fluxes, which, besides pro- tecting the fused weld metal against injurious outside influences, must as- sist the elimination absorbed gases, and the injurious compounds formed, from the liquid metal raising its fluidity and widening the freezing range and decomposing the unde- sirable compounds already formed. view the absorbing power fused nickel for reducing gases, the one hand, and for oxygen, the other, the oxy-acetylene flame must controlled with more than usual care, the most desirable being slightly reducing flame with only slight feather (approximately in. long) beyond the tip the luminous slightly higher degree re- duction will immediately become evi- dent increasing the porosity the weld, while oxidizing, even neu- tral, flame may cause excessive oxida- tion the melt. Another important consideration this connection the size the flame; that say, the proper size the burner tip. the flame too small, melting the nickel pro- ceeds too slowly, the maximum heat the burner covers too area, and the fused metal solidi- fies too rapidly. these circum- the gases absorbed are not afforded sufficient time escape, re- the metal and giving rise porous welds. If, the other hand, the burner tip too large, the excessive heat will cause boiling Welding Technique for Nickel and Nickel-Rich Alloys the weld metal, even burning through the seams. impossible here give exact figures for the proper size the welding flame, which largely de- termined the character the weld and the shape and size the parts welded. safe rule for the nickel welder employ flame large possible without caus- ing boiling the weld metal. Oxidizing Materials Welding Rods Welding rods welding wire used for this purpose consist nickel (or nickel alloys respectively) containing manganese, magnesium, aluminum, other deoxidizing agents, manganese being the addition usually preferred. Much, however, depends percentage the deoxidizing agents added. the case manganese, 0.1 0.3 per cent may considered the safe range, the exact percentage depending upon the material welded and the amount manganese con- tained the basic material. Many the nickel products sold the form sheets, tubes, etc., con- tain small percentages manganese order improve their welding quality, and obvious that for ma- terial this type the manganese con- tent the welding rods should maintained proportionately low. The customary manganese content nickel parts welding quality ranges about 0.2 per cent and for material this type the welding rod should contain not more than about 0.1 per cent manganese. excess manganese not desirable, although the disadvantages possibly accruing from this source are not nearly serious lack deoxidizing agent the welding rod material. Some authorities advise addi- tion small percentage mag- nesium besides manganese order decompose possible sulphides the weld. Experiments with alloys this type have not always proved suc- cessful, although there appears reason why this should the centages, will also decompose nickel phide which enters the slag produced the fluxing material. The amount required for this purpose, however, represents undesirable excess, that another reagent possessing higher affinity for sulphur appears desirable. There doubt that the failures obtained with nickel-manganese rods containing magnesium are due ex- cessive magnesium content, which, af- ter decomposing the traces sul- phur the melt, magnesium the weld produce un- desirable alloying conditions. should expressly stated, for this reason, that such excess formed even very small additions mag- nesium the welding rod this additional the required manganese content. Where mag- nesium added, this should de- ducted from the manganese. For in- stance, where ordinarily the man- found be, say, 0.25 per cent and average sulphide content of, say, 0.01 per cent the weld metal the addition 0.05 per cent nesium, the welding rod metal should contain not more than perhaps 0.22 per cent manganese and 0.05 per cent magnesium. This point not un- important may seem, view the small quantities involved, but since producers are not rule par- ticularly careful adding magnesi- special welding rod materia! containing manganese, pointing results sometimes obtained with these rods are easily explained. Common Borax Not Desirable Flux The fluxes employed curative character, the property including pronounced vent action the sulphides and ides nickel. Common bor: universal flux, although employed for this purpos ciently large quantities the fluidity the weld does not possess sufficient power for the injurious pounds present counte brittling tendencies process. Besides increasin welding fluxes must The Iron Age, September 14, 1933 —25 . | ite. VW | i 4 i > - ‘ | he com- h ; great deoxidizing and solvent capaci- ties. Borax considerably improved boric acid additions, while mag- nesium chloride similar salts pro- vide the deoxidizing and solvent re- action required. Practically all fluxes, such the In