The Iron Age 1938-06-23: Vol 141 Iss 25

FRITZ FRANK President VAN DEVENTER Editor ROWAN News Editor A. FINDLEY Editor Emeritus E. WRIGHT Editor Machinery Rditor Art Editor Vetallurgical Bditor Associate Editors PHAIR JURASCHEK Consulting Editer Resident District Editors Pittsburgh Chicage Cleveland Detroit Editorial Correspondents Londen, England Cincinnati FRAZAR Boston Hamburg, Germany L. E. Mey we CHARLES Post Milwaukee Sen Francisco ASA ROUNTREE, JR. Toronto, Ontario Birmingham ALLISON Roy EDMONDs Newark, N. J. St. Lowie Buffalo and Published CHILTON COMPANY (Incorporated) Publication Office Ohestnut and 56th Sts., Philadelphia, Pa. SANDBRSON Editorial and Executive Offices 239 West 39th New York, N. ¥ OFFICERS AND DIRECTORS A. MUSSELMAN, President Vice-President JOSEPH 8. HILDRETH, = GEORGE H. GRIFFITHS. KVERIT B. TERHUNE, WILLIAM A. BARBER, ‘treasurer JOHN BLAIR MOFFETT, Secretary JOHN VAN DEVENTER JULIAN CHASE THOMAS L. KANE CHARLES 8. BAUR G. CARROLL BUZBY P. M. PFAHRENDORE BAUR, General Advertising Manager DIX, Manager Reader Service Member, Audit Bureau of Circulations Member, Associated Business Papers Indexed the Industrial Arts Index. Published every Thursday. Subscrip- tion Price: United States and Pos- sessions, Mexico, Cuba, $6.00; Can- ada, $8.50; Foreign, $12.00 year. Single copy, 25 cents. Cable Address. STAFF Emerson Findley, 621 Union Bidg., Cleveland B. L. Herman, Chilton Bidg., Chestnut & 56th Sts., Philadelphia, Pa. H. K. Hottenstein, 802 Otis Bidg., Chicago H. E. Leonard, 239 W. 39th St., New York Peirce Lewis, 7310 Woodward Ave., Detroit Ober, 239 39th St., New York W. B. Robinson, 428 Park Bidg., Pittsburgh Warren, Box $1, Hartford, Conn. RON Cont Parallels Meet Appraisal Cold Heading Effect Chromium Cast Structural Welding Germany Engineering and Economics Belt Selection. Heat Treating and Process Controls Automotive Industry Statistics the Metal-Working Industry Washington News THE NEWS BRIEF Rate Activity Capital Goods Plant Expansion and Equipment Buying New Industrial Literature Products Advertised Just Between Two Index Advertisers Copyright 1938 Chilton Company in, le n. 0 id aire d 7 106 Your Guide Certified, Uniform High Quality The Ryerson Stock List your guide large and diversified stocks steel—the only stocks Certi- fied Quality Steels the country. You have definite assurance getting steel which has the features most desirable the particular kind you whether deep drawing quality sheet, high tensile structurals, easy machining screw stock high finish stainless. alloy steels you get still another added ture. Ryerson sends accurate data every delivered that your heat treater can easily desired service never before any steel-service company. When you want good, uniform steel, turn Ryerson Stock List. You will find complete sizes and shapes. Immediate shipment assure@ Joseph Ryerson Son, Inc. Plants at: Chicago, Milwaukee, St. Cincinnati, Detroit, Cleveland, Buffalo, Boston, Philadelphia, Jersey § be t the average run press work Presses THREADING MACHINES.—Landis Ma- chine Co., Inc., Church Fifth Sts., Waynesboro, Pa. Folder describes the new Landmaco quadruple head thread- ing machine designed especially handle the maintenance and produc- tion threading operations railroads. Features the machine include eight speed selective type gear box and individual spindle control. ELECTRIC UNIT HEATERS. Electric Air Heater Co., 555 South Byrkit Street, Mishawaka, Ind. Bulletin No. 38-A covers the construction, operation and application Electromode unit heaters for commercial and industrial use. The adaptability the Electro- mode principle heating clearly shown, particularly applied iso- lated, hard-to-heat places. ROLLING GRILLES.—Kinnear Mfg. Co., 2450-70 Fields Avenue, Columbus, Ohio. Rolling grilles that combine architectural beauty with practical de- sign are illustrated this booklet. The application these grilles indus- trial and commercial buildings and pri- vate homes shown, and construction features are discussed detail. GRINDING MACHINES. Cincinnati Grinders Inc., Columbia Road South Street, Cincinnati. Folder announces new universal grinding machine with and in. swing. Features the grinder include one-piece bed, wheelhead with multiple shoe type spindle bearings and self compensating spindle bearings. KOPPERS YEARBOOK. Koppers Co., Koppers Bldg., Pittsburgh, Pa. This book contains annual report the operations the company and dis- cussion the functions each sub- sidiary unit. Wages and employment 1938 are carefully covered and prop- erty and corporate charts are included. STELLITE CUTTING TOOLS. Haynes Stellite Co., 205 East 42nd Street, New York City. Illustrated folder describes the new Haynes Stellite-2400 high-pro- duction cutting alloy. Sizes and styles tool bits are listed, and data are given what materials they will ma- chine economically and general re- sharpening practice. STAINLESS Steel Co., Brackenridge, Pa. illustrated book- let describing Allegheny metal, stain- less steel that may stamped, spun, cast, machined and welded. Booklet contains many examples the use the metal various industries. COPPER-BEARING STEEL SHEETS.— Bethlehem Steel Co., Bethlehem, Pa. Folder describes Beth-Cu-Loy copper- bearing steel sheets that are claimed IRON AGE, June 23, 1938 give 200 250 per cent greater rust resistance but per cent extra cost. Also included are results sev- eral exposure tests showing average life different metals. WIRE AND STRIP ANNEALING. Lee Wilson Engineering Co., 1370 Blount Street, Cleveland. Booklet discusses and illustrates small, cylindrical, ver- tical tube-type furnace designed take care small miscellaneous batches where heat treating specifications vary from batch batch. Design said make possible exceptionally close control temperatures the top and bottom the charge. GAS CONDITIONING UNITS. Co., Church Street, New York. Circular No. 380 notes briefly the reasons for the growth the use protective atmospheres furnace work, and describes the features the company’s standard unit. INDUSTRIAL TRUCKS. Baker-Raulang Co., 2618 West 25th Street, Cleveland. This well illustrated, 18-page bulletin provides rapid means determin- ing the type industrial trucks best suited perform given duty. Ele- vating, crane, platform trated actual service, and principle specifications are given. ROLLER CONVEYORS.—Palmer-Bee Co., 1700 Poland Avenue, P.O., Detroit. comprehensive catalog devoted describing and illustrating gravity and power driven roller con- veyors. The construction and applica- tion these conveyors are covered great detail and numerous useful en- gineering data tables are included. SHEET METAL PRODUCTS. Milcor Steel Co., South West Burn- ham Street, Milwaukee. well pre- pared spiral-bound booklet listing the numerous sheet metal products and fire-proofing materials manufactured the company. addition prod- uct descriptions, the booklet contains photographs and biographies the officers the Milcor company. FOUNDRY MELTING METHODS.—Whit- ing Corp., Harvey, Ill. brochure foundry melting methods that will value all foundry- men. Cupolas, rotary furnaces, side- blow converters, air and cradle fur- naces, and duplexing equipment are all thoroughly discussed and advantages each type, and its particular field application, are pointed graphs and line drawings are used advantageously illustrate the text. MEASURING INSTRUMENTS.— General Electric Co., River Road, Schenectady, the title this unusual booklet that tells briefly the contributions en- gineers and scientists the art measurement. How instruments are de- signed, constructed and tested are dis- cussed detail and many striking photographs illustrate the text. RADIANT TUBE HEATING ELEMENTS. —Surface Combustion Corp., 2375 Dorr Street, Toledo. Folder covers the ap- plication horizontal gas-fired radiant tube heating elements furnaces with and without controlled atmospheres. Operating data clean hardening furnace and drawing, annealing and normalizing furnace are given. PILLOW BLOCKS.—Shafer Bearing Co., East Wacker Drive, Chicago. Bul- letin discussing Super bearing pillow blocks. away photographs, diagrammatic drawings, specifications, and descriptive text. PNEUMATIC RIVETERS.—Hannifin Mfg. Co., 621 South Kolmar Avenue, Chi- cago. Portable and stationary pneumatic riveters are illustrated and described this 12-page bulletin. Specifications are included. INGOT MOLD LIFTER.—Cullen-Friestedt Co., 1300 South Kilbourn Avenue, Chi- cago. Bulletin covers multiple handling ingot molds. Photographs showing actual operation included. DIE WELDING. Ampco Metal, Inc., 3830 West Burnham Street, Milwaukee. Ampcoloy 44, alloy designed for butt and flash welding die material. Phys- metallurgical aspects and service data are included. | | | | | | 4 | | | | q | . | | THE IRON AGE ... JUNE 23, 1938 ESTABLISHED 1855 Vol. 141, No. Parallels Meet what happened last week, firmly convinced that those early developers projective geometry, Lobatchewsky and Riemann, were right. Parallel lines meet, they keep going long enough. was privilege and pleasure preside, last Tuesday, Industrial Confer- ence Detroit which some 700 outstanding leaders industry and labor met consider the way out our present unfortunate and unnecessary situation. This meeting, sponsored the Detroit chapter the National Industrial Adver- Association, was addressed Donald Richberg, former head the NRA; Lewis Hines, National Director Organization the AFL, and Bennett Chapple, vice-president the American Rolling Mill Co. Where you could find three men more widely differing spheres experience and responsibility, would hard say. Richberg, lawyer, former head the NRA, man who liberal regard economic legislation, who has sat the inner councils Washington, but who has kept his feet the ground. Hines, who began work the age apprentice glass blower, left that de- clining industry become metal polisher, became general organizer for that craft, later Director the Bureau Mediation Pennsylvania and now National Director Organization the AFL. Chapple, noted the Armco radio hour, who for years has di- rected the publicity and the public relations company that has never lost day's production more than years because labor troubles. These men went Detroit present their views what steps should take overcome the depression and recreate jobs industry. Their papers were prepared independently one another without any leading suggestions from the sponsoring committee. All that was asked them was how get out this You would have expected find three widely differing opinions from these three men. But you did not. Instead, their thinking throughout ran exactly parallel lines and hence the same direction. nutshell, was this: must get together common ground, for the pur- pose making business better and creating jobs. There room this common There are enough averagely well intentioned people Government, Labor, and Ownership Industry attain that objective through cooperation and through consultation. will get together, can disregard the few egomaniacs who each these spheres would rule ruin. You not have bend parallel lines bring them together. : | bes 2 7 t 's 4 a | | | | Appraisal Cold Heading this second article the series, the author reviews the general principles operation cold heading machines the design details the three commercial types equipment. Trends speed and capacity are indicated some headers placed the market recent months. wire drawing attachment eliminates age hardening ef- fects cold drawn wire for heading work. The third ar- ticle will discuss die material and its heat treatment, well general principles die design. ap- peared the issue June COLD heading machine con- sists essentially roll feed for the wire, cut-off knife and transfer mechanism, and the header proper. The usual arrangement fixed set dies and reciprocating head gate which the punches are carried. Machines are made single, double and triple stroke types, which means that takes that num- Punch Finishing punch 24—THE IRON AGE, June 23, 1938 ber blows with different punches complete the piece. Quadruple headers combine two units. far the majority the work done two stroke machines, which the first stroke coning bulbing operation and the second, finishing stage the extent that round head final depth formed. Hexagon square heads are formed Adjustable Connection “Cam compensator adjustment trimming dies second opera- tion, with hand hopper feed. Ex- trusion the shank smaller di- ameter than the wire can accom- plished the fixed die the header during the subsequent trimming operation. Dies are the solid open type. From solid dies, work ejected knockout pin which cam Open dies are split vertically and are opened slightly the completion the finish stroke, allowing the part readily ejected. stick solid die, since there can obviously draft part having the character bolt cap screw. Solid die headers are used for large variety comparatively short work and for pieces accurate diameter, limited length and high quality fin- ish; consequently open die headers are used for proportionately long work, well for work which the parting line produced the shank not objectionable. new line solid Waterbury- Farrel heading unit and punch shift- For every stroke the crank, the punch alternately moved either down. Long pieces tend. | | | | | 7 3 4 Practice die headers being offered, however, handle work with shanks diam- eters length. Extrusion dies are necessarily the solid type, but can used com- bination with open dies. Generally open dies are made two die blocks, with semicircular grooves each the four faces. the time heading, these dies are wedged place solidly, and matching fresh sets grooves and turning the blocks end for end, the die life can multiplied much eight times the life obtained from solid die. Because header always work- ing the elastic limit the wire material and beyond, the machines must built extra rugged, with gen- erous casting sections and oversize bearings. addition, several safety features are incorporated. There usually shear pin cast iron breaker plate the cut-off mecha- nism between the eccentric crank plate and the cutting off slide. the larger sizes, also, the knockout cam actuated through breaker plate. The frame may high tensile cast iron cast steel. Crankshafts are generally heat-treated alloy steel. There are three commercial head- ing machine manufacturers. Two them, the Manville Machine Co. and the Waterbury Farrel Foundry Machine Co., both Waterbury, Coan., have made machines this type for many years. The National FRANK OLIVER Associate Editor, The Iron Age ° Machinery Co., Tiffin, Ohio, well known makers hot forging ma- chines, newcomer the cold heading field. All three companies make machines the general design described above, the chief differences being the method cutting off the wire blanks, the means employed shift the punches, the construction the ejection knock-out device, and the crankshaft mounting support. There have also been worthy modifications the conven- tional design and these will pointed out later. Gate Design The vertically reciprocating which the punch holder attached design common both the Man- ville and Waterbury-Farrell headers, although the details vary. section the latter’s design shown illustrate the principle opera- RIGHT OME distinctive fea- tures found the National cold header are the long over-arm heading slide and the oscillating heading tool movement. ° ° ° BELOW Waterbury No. in. solid die, header without doubt the largest ever built. weighs over tons. tion. The heading unit this two- stroke machine consists gate, vertical punch slide dovetailed the gate, punch holder the slide, connecting rod pitman with self- alining connection the gate, and punch shifter driven off camshaft, which geared the crankshaft half speed. The spring compensator and cradle connection the slide takes lost motion and provides for adjustment. The heading tool movement the National two-stroke machine quite different. Instead sliding and down gate, the bolster given oscillating motion about The bolster automatically locked each the heading positions, and automatic relief prevents damage the bolster tools, should any inter- ference prevent the completion its oscillatory movement. oscillatory motion also applied the cut-off tool and carry-over motion. The cut- ter arm oscillates about pivot point and operated circular cam, timed approach the stock slow speed without shock, and the action said one cutting rather than breaking off the stock. After the blank severed, carried the heading position gripper finger operated another circular cam. Both cutter and gripper are protected relief device, rather than braker plate shear pin. The same slow-start principle applied the work ejector cam prevent up- THE IRON AGE, June 23, “4 ° ° re 4 > setting the end the work when the ejector pin comes contact with it. the design its cold headers, National has carried over features found its hot forging machinery, such heat-treated cast steel frame and long overarm sup- port for the heading slide. The over- arm extends over and beyond the crankshaft, giving bearing support the slide both sides and assuring alinement all times. Another inno- vation the location the feeding mechanism slight angle the machine compensate for the dragging action the shear blade and thus get more nearly square end the blank. Cold headers range capacity from wire rod. Water- bury-Farrell the only company making machine above bolt size. One its latest machines largest capacity, solid die double stroke machine, weighs over tons, driven 75-hp. motor and has output pieces per min. High Speed Types contrast, the latest Waterbury- Farrel high-speed “Hypro” header double-stroke, solid die machine that delivers 450 blows per min., 225 pieces, the smaller size, which has capacity 3/16-in. wire and work in. long under the head. The belt driven machine weighs 3300 high speed ma- chine weighs 2200 and delivers 250 pieces per min. The manufacturers state that spe- cial attention has been paid the safe and efficient operation the ma- chines these high speeds; that they are unusually well-guarded, automati- 26—THE IRON AGE, June 23, LEFT PERATING side Waterbury- new header capable heading screw blanks from 3/16 in. wire the rate 225 per min. RIGHT HIS Manville ball header single- stroke type capable producing 7/32 in. balls from cold drawn wire the rate 350 per min. cally lubricated, and provided with mechanical safety devices which con- tribute materially their high ef- ficiency. The roll feed the Hypro pro- vided with auxiliary mechanism which makes impossible feed shorter length wire than needed. The device which cuts off the wire and transfers the blank into heading position has also been especially de- vised for high speed. adjustable for timing and for locating the knife relative the dies. Similar features are also found the National high- speed header. Waterbury-Farrel has also recently redesigned strengthened standard line solid die, double stroke headers seven sizes from in. meet the requirements for cold heading high carbon alloy steels high speed. These changes include the use entirely new frame extra large cross-sectional area and improved cut-off mecha- nism. The cut-off bar large diameter and operates through the frame right angles the wire, with its inner end supported such way that the knife held flush with the face the die, thus assuring clean shear. The hinged “fiddle bow” formerly used hold the blank the cut-off knife, has been replaced spring finger fastened the knife. New Ball Headers Manville has recently announced interesting addition their header line. The machine, known ball header, forges steel balls and solid die type, single stroke. Accord- ing the maker, balls shaped this header require about per cent less grinding than now necessary with any other machine this type. This due the design new maga- zine quill cut-off which permits per- fect right angle cut, thereby keeping the finished blank within exception- ally close tolerances. producing 7/32-in. balls, product rate 350 per min. has been achieved, the highest speed ever attained with this type machine. Features include accurately balanced crankshaft and forced feed lubrication. Tubular Rivet Headers Another new header made Man- ville machine that produces tubu- lar rivets single station operation two blows. The machine unique that performs the difficult opera- tion punching extended hole the blank while held the same position occupies when headed. This eliminates transferring the work from one set tools another. The normal rate production 150 blanks per min., the maximum size | | i baw’ il] which 3/16 in. With few minor changes, such the fitting new dies, this machine may used form large variety metal parts. Waterbury-Farrel also make tu- bular rivet header, placed the market essentially modified solid die, toggle header with special attach- ments. This machine employs one set tools for making the head two blows, and additional set for form- ing the tubular portion, working simultaneously successive rivet blanks. The special equipment in- cludes spring finger transfer mecha- nism carry the work from one die the other. This method manufac- ture feasible where the depth the hole does not exceed one wire diam- eter. For longer holes, secondary drilling operation required. This machine made two sizes make in. Production 100 pieces per min. Wire Drawing Attachment There are two types attachments made for wire drawing hot rolled rod immediately before sent into the headers. The Ajax Hogue machines, made the Ajax Mfg. Co., Cleve- land, are wide use. newer type made the B-W Mfg. Co., De- troit. Such device enables the user purchase the cheaper rod material place cold drawn wire, and sim- plifies stocking, since one base size rod can drawn several diame- ters. Principally, however, the ad- vantage lies eliminating the aging effect cold worked material. cold headed immediately after being wire drawn, the material exhibits plasticity close that the original hot rolled stock, and subsequent heat treatment the cold headed product frequently not necessary, even for the SAE 1035 steels. cold drawn wire allowed stand unworked little min., the other hand, dif- ference the physical characteristics will noted. (The same aging effect seen severely cold rolled sheets, which are re-worked cold roller leveler process. Using this technique, the life the cold heading dies said greatly improved, running high 250,000 ° LEFT TION standard header this Manville hollow rivet machine, two blow, single station type. Production 160 blanks per min. RIGHT FEATURE the National line the almost com- plete enclosure all moving parts. ° pieces, compared with 50,000 where cold drawn wire used that has age hardened. Questions straightness and wire lubrication also enter here. Another economy claimed for the ma- chine that the rod does not have pointed and can through the machine very quickly. The B-W attachment incorporates pushing mechanism start the rod through the drawing die, which conventional tungsten carbide type, and intermittent pulling mecha- nism operated through rocker arms and links. This unit replaces the continuous roll feed mechanism header and can applied any standard machine. The rod fed hand into the pushing grip mecha- nism directly from the reel and the machine started. The first second push gets the rod started through the drawing die, and when the wire comes out, carried into the sec- ond grip mechanism, which takes hold and begins pull. The push mecha- nism may then disengaged. The speed drawing only about ft. per min., compared with 250 ft. ordinary wire drawing benches, that the heating slight and the life the drawing dies greatly prolonged. Some dies have drawn high 800 tons wire before being discarded. The average reduction 0.060 in. Toggle Type Machines the cold forming hard metals like steel, time element. For in- tricate work, order give the metal chance flow, machine with toggle press action some- times more advantageous than faster crank-type machine, such those that have been described. standard upright toggle usually employed, but obviously wire feed from coil stock cannot used. most this work second THE IRON AGE, June 23, / ‘a- bays” ¥ § operation processing, this drawback not serious. machine closely allied bolt headers automatic nut forming machine made Waterbury-Farrel. This machine cold upsets double chamfered hexagon nut blanks from wire stock with minimum scrap. There are four punches and four dies arranged horizontal plane, and the work transfererd automatically from one the other succession. After the blank cut off, squared punch, then trans- ferred the second die and dome cone shape formed each end the blank. the third die, the hexa- gon shape with chamfer both sides formed, well two central re- cesses. These depressions form coun- tersinks for the hole that punched through the. last die, and the slug scrap only about half the thick- ness the nut. The nut blanks are delivered through tube, free from scrap. Production nuts per min. the size and 100 the machine. Usually high sulphur, basic open hearth steel used facilitate the subsequent tap- ping operation. High production, homogeneous grain structure, excel- lent finish and low cost are some the advantages pointed out the manufacturer. Other nut machines are made that employ punching and stamping meth- ods, without there being any attempt upset cold form the original stock, and hence are not pertinent this discussion. bolt and cap screw departments, aside from the cold headers, there are number pieces related machin- ery that govern the layout, generally from the point view efficient flow materials. Some plants use departmental layout, with headers 28—THE IRON AGE, June 23, 1938 one group, trimmers another, roll threading and cut threading, heat treating and plating other sections. This the commonest arrangement found bolt factories. One the large electrical equipment manufac- turers, however, has group head- ers one row and line slotters across the aisle. Behind them smaller number thread rollers and tumbling barrels for removing burrs. The thread rollers face double deck gravity roller conveyor leading the washer and heat-treating furnaces the same room. Another section the same department has group larger headers, with forming the hexagon heads, shavers, pointers and slotters grouped behind them the other aisle. Another roller conveyor takes the bolts tote boxes the thread rollers main One the most efficient layouts found motor car plant. mez- zanine deck battery cold head- the latest ad- vances the B-W wire drawing attachment for cold headers that permits rod cold drawn immediately be- fore being cold headed. pusher, left, starts the rod through the draw- ing die and recipro- cating puller takes the other side and feeds directly into the header. ers used cut off and size wire for cylinder head studs. Blanks ejected from the headers are led tubes two thread rollers, one above the other arrangement heavy I-beams. After being roll threaded one end, the stud fed pipe the second threader, but the way upended rocking fixture. The set-up entirely automatic and pro- duces 450,000 500,000 studs Although tote boxes and lift trucks are commonly used bolt depart- ments, conveyors are wider use, particularly the packing end the line. The most efficient manner for transporting coil stock the cold headers overhead mon- orail, and this the method used some the largest manufacturers. Since changeover time factor hourly output, the tendency use heavier coils, weighing 600 more, place conventional 200- Ib. coils. (To Continued) Fire Clay Ladle Sleeves Tested National Bureau Stand- ards has just published the results study determine the best fire clay ladle sleeves for steel foundry service. The results obtained may summarized part follows: The brand sleeves which gave the most satisfactory results service was very refractory, had fairly high porosity, fairly uniform high expansivity, and high extensibility. great deal variation the properties and service results was noted different sleeves some the brands indicating lack uniform- ity the product. There sharp dividing line the degree refractoriness between the two brands highest refractoriness and the remainder the brands. would appear desirable specify refractoriness requirement. The speci- fied pyrometric cone equivalent ex- pressed approximate temperature equivalent should greater than, least equivalent to, the maximum temperature the molten metal enters the ladle. would also seem desirable specify porosity require- ment not less than per cent. minimum .extensibility value and linear thermal expansion without er- ratic changes due silica inversions are also possible and desirable require- ments. refractoriness require- ment specified, not much appears gained specifying limits the chemical composition. | | ad- nent that cold be- ded. the raw- pro- and the for the avy the The into ient use Ib. ness the opinion, the growth cast iron exposure ele- vated temperatures due to: First, the decomposition ce- mentite and pearlite into ferrite and graphite. Although not the principal cause growth, this the first step every iron with which the author familiar, which has been exposed temperatures above the pearlite de- composition point (about 800 deg. The breaking down cementite and pearlite aids growth the fol- lowing three ways: (a) The decomposition products, ferrite and graphite, take more space than the constituents originally present. (b) The graphite formed offers in- gress oxidizing gases. (c) The decomposition products are mechanically weaker than the ce- more likely crack under the strains set different expansions and contractions. IT. Second, oxidation. most ser- vice, this the principal cause growth, for the following two reasons: (a) and iron oxide Effect Chromium Growth ommercial Cast lron ° ° ° REBECCA HALL SMITH Metallurgist, Detroit ° the issue June Mrs. Smith reviewed the history investigations the growth cast iron elevated tem- peratures and detailed her at- tacks the problem. Herein, the author's report concluded with outline her own ideas the causes growth, to- gether with summary data the retarding action chromium. formed the oxidation silico-fer- rite are much more bulky than the latter, and therefore tend both in- crease the volume the casting di- rectly, and exerting pressure which may cause cracks; (b) The gas formed the oxida- tion graphite exerts pressure, caus- ing the formation tiny fissures along which more oxidizing gas can enter. Oxygen present the air around castings all the time; but does not cause their rapid deterioration except ° ° high temperatures, because can- not penetrate into the interior the metal. However, cast iron heated, expands; and because iron expands faster rate than graphite, small cavities are formed along the graphite flakes. along these cavities that oxidizing gases enter. any one heating, probably the oxides produced would eventually fill the cavities around the graphite flakes, and thus effectively prevent further oxidation. With alternate heating and cooling, however, there cycle set up: the oxides formed high temperatures interfere with contrac- tion the iron cooled; cavities open the iron re-heated, oxi- dizing gases enter, more oxides are formed, and the iron thus continues grow. For this reason, the al- ternate heating and cooling such plications, causes much more rapid growth than would take place the casting were simply raised high temperature and held there. the photomicrographs (see issue June page 45), the oxides are gray, while the remaining graphite black. The swollen appearance which characterizes graphite formations THE IRON AGE, June 23, 1938—29 ture num er- oxidized irons appears due the formation oxides iron and silicon the immediate vicinity the graphite flakes. Naturally, the oxidizing gases enter along the cavi- ties the graphite flakes, they would attack first those portions the cast- ing which are near hand; and the gray oxide formed would, low magnifications, give the appearance alternately heated and cooled, even temperatures under 800 deg. F., permanent growth takes place, due the expansion and contraction the casting. Pure iron expands when heated, but since contracts equal amount cooling, there perma- nent change volume. Commercial cast iron, however, discontinuous material, made two more con- for Ohio Electric Mfg. Co. motors are made uniform throughout this annealing operation. swollen graphite. secondary cause for this swollen appearance may the depositing graphite from car- bide decomposition. Third, expansions and contrac- tions. These may purely physical, chemical, allotropic nature. (a) Physical: When cast iron Cast Iron During Re- peated Heating and Cooling,” Andrews and Higgins, Journal Iron and Steel Institute, Vol. 112, 167, 1925. and Wear-Resistant Malleable Castings,” Rebecca Hall, American Association, Heating 800 Deg. 1100 Deg. F.,” MacPherran and R._H. Kruegar, Transactions, American Foundrymen’s Association, vol. 38, 826, 1930. 30—-THE IRON AGE, June 23, 1938 stituents which each have different rate expansion. When heated, each the different constituents expands its own rate, and stress set between the various micro-portions which results cracks. oxi- dizing atmosphere, these cracks offer easy ingress for oxidizing gases, and thus increase oxidation; but even atmosphere, these cracks contribute the increase volume and deterioration the cast- ing. (b) Chemical: temperatures be- tween 900 deg. and 1300 deg. F., the decomposition pearlite, producing ferrite and graphite, takes place. This reaction, which has such marked ef- fect growth, was discussed de- tail above. One type iron recom- mended for heat-resistance has elim- inated this factor, because all ferrite and graphite cast. (c) Allotropic: The change from alpha iron gamma iron, about 1340 deg. F., accompanied marked change volume. Each time the casting passes through the range including this temperature, the expan- sion contraction which occurs causes severe strain. Another type heat-resistant iron eliminates this fac- tor, being austenitic cast. The author recognizes that the tem- peratures and atmospheres involved may cause one another the fac- tors mentioned above causes the growth cast iron, the most important for that particular service. Effect Chromium From the photomicrographs (see issue June page 45), easy obtain clear picture the role chromium retarding the growth gray cast iron. Chromium stabilizes both cemen- tite and pearlite, interfering strongly with the graphitization which would, unalloyed irons, take place high temperatures. evident from the photographs, both massive carbides and pearlite remain intact, even after exposure 65-hr. cycles 1700 deg. F., far above the decomposition range unalloyed pearlite. has heen stated the past that carbide-form- ing element stabilizes the massive car- bides, but that the presence silicon prevents its stabilizing the The present author can see differ- ence this respect between the mas- sive carbides, and the carbide the pearlite. Obviously, from tures, the pearlite stabilized, with the following results: (a) does not form bulky decom- position products (b) Since graphite not formed, there less ingress for oxidizing gases (c) The structure the casting still consists strong pearlite, which can better withstand the stresses set different expansions and con- tractions. Several years ago, when investigat- ing the effect chromium mal- leable iron, the author found that even when additional silicon was added with the chromium, the latter still sta- bilized the little 0.22 per cent chromium would retard graphitization white iron during | | | i | | | | | 10-day annealing cycle, resulting structure nodular temper carbon pearlitic matrix, instead fer- ritic one. well known that when large amounts chromium are present ferrous metals, forms (under oxi- dizing conditions) protective film chrome oxide. The photomicrographs show clearly that neither the matrix nor the graphite the chromium- containing iron were preciably oxidation, although ex- posed for 300 hr. oxygen at- mosphere 1700 deg. the author’s belief that the chromium this iron, although only per cent was added, acts some such manner the chromium stainless steels: that when oxidizing gases enter (as they must, some extent), the chromium reacts with them, forming minute layers oxide, probably fol- lowing the lamellae the preventing further oxidation. There is, also, the further consideration that the chromium iron originally had smaller graphite flakes, which would offer less entrance gases. Chromium strengthens the iron, and thus makes more able with- stand the stresses set thermal changes. brought out before, the chromium-iron stronger than un- MacPherran have shown that stronger when tested high temperatures; and after cool- ing, the tests cited earlier this article showed was several times stronger than iron. therefore better equipped withstand the inevitable strains resulting from alternate heating and cooling. summation, the three main causes the growth cast iron after ex- posure elevated temperatures are, the author’s opinion, (1) carbide decomposition, (2) oxidation, and contractions. Since chromium cast iron stabilizes the carbides, retards oxidation, and strengthens the iron, its retarding ef- fect growth explained. REFERENCES (1) Beddoes, “Account Some Ap- pearance Attending the Conversion Cast Iron into Malleable Iron,” Philo- sophical Transactions, vol. 81, 173, 1791. Journal Iron and Steel Institute, vol. 83, 196, 1911. (3) Hurst, “Growth Gray Cast Iron Repeated Heating,” Foundry, vol. 46, 227, May, 1918. (4) Hurst, “The Prevention Growth Gray Cast Iron,” Journal Iron and Steel Institute, vol. 98, 199, 1918. (5) Hull, “Growth and Deteriora- tion Gray Cast Iron Under Repeated Heatings,” Foundry Trade Journal, vol. 26, 412, 1922. (6) Levi, “Heat Resisting Cast Foundry Trade Journal, vol. 31, 549, 1925. (7) Donaldson, “Low Tempera- ture Heat Treatment Special Cast Irons,” Foundry Trade Journal, vol. 31, 517, 1925. (8) Hurst, “Heat Treatment and Volume Changes Gray Cast Foundry Trade Journal, vol. 32, 1925. (9) Kennedy and Oswald, “Effect Various Alloys the Growth Gray Iron Under Repeated Heatings,” Transactions American Association, vol. 34, 871, 1926. Growth Gray Cast Iron,” Transactions American Institute Mining and Metal- lurgical Engineers, vol. 95, 219, 1931. (11) Bolton and Bornstein, Certain Mechanical Properties Gray Cast Iron and Malleable A.S.T.M.- A.S.M.E. Symposium Effect Tem- perature Metals, 299, 1931. (12) Donaldson, “Industrial Steels and Chemistry and Indus- try, vol. 50, 838, 1931. (13) Scheil, “Growth Cast Iron,” Archiv fur das vol. 61, August, 1932. (14) Wood, “Growth Gray Cast Iron,” Iron Age, vol. 132, 12, July 20, 1933. (15) Thyssen, “Influence Silicon and Aluminum the Resistance Cast Tron High Temperatures,” Journal Iron and Steel Institute, vol. 130, 153, 1934. Patents Issued for Changing Cold Metal Into Open Hearth ATENTS process and the apparatus for mass charging cold metal into open-hearth fur- naces through improved furnace con- struction have been issued Paul Douglas and John Rogers, Cleve- land Heights, Ohio, assignors the Wellman Engineering Co., Cleveland. Through charging large bulk one time, reductions power and fuel consumption are aimed at, along with speed operation and savings the maintenance cost the charging equipment, well the furnace it- Reconstruction the front the furnace the principal feature. The furnace fitted with removable front which substantially long hearth and which can readily extracted and lifted and replaced admit the insertion the charg- ing pan receptacle having floor area similar size that the fur- nace hearth, thus enabling the entire hearth filled with cold metal other material one charging opera- tion. the same time, the furnace front provided with hot metal and inspec- doors arranged and functioning the usual open-hearth furnace. This provision removable furnace front comparable length with the furnace hearth, and thereon individually movable doors similar those use the non- movable permanent open-hearth furnace front, the extracting and lift- ing mechanisms for the furnace front, and the operating devices for the vari- ous doors, each capable functioning without interference with the other. constitute features which are new. The charging equipment consists charging machine proper constitut- ing one unit, and suitable receptacle pan having flexible rolling bottom with floor area substantially equal the entire hearth area charged, which may loaded with the cold metal charge any suitable point and brought and deposited the cradle the charging machine which can then moved along the track front the furnace charged, and after the charging operation completed, the empty pan may re- moved from the cradle and again filled with cold metal. charging furnace, when the charging machine has come stop, the furnace front removed and the cradle and the loaded pan are run into the furnase the full distance, then retracted, and, while being retracted, the pan floor caused roll under- neath the pan frame, the rear wall the pan then being held stationary and after the entire charge deposited progressively the hearth layer approximately uniform thickness, and while the platform and cradle are still being retracted, the pan floor rolled back onto the upper side the pan frame. When the cycle operations completed, the empty pan may mechanism, lowered onto the transfer car, and refilled for charging another furnace. The engineers point out that the improved charging process obviates the necessity cutting the scrap the relatively small charging box size required the dimensional limitations the furnace doors, and make pos- sible the filling each box with sufficient amount metal. Also, asserted that the rapidity with which possible fully charge the largest furnace the new method reduces the time per heat with given time. THE IRON AGE, June 23, le- all gh ic- ith al- Structural elding Progress DIPL.-ING. BONDY Consulting Engineer, London, England. first all-welded buildings Germany, other countries, were very similar their riveted predecessors. The designer those times was mainly concerned with re- designing the connections only, while the members the structure were about the same shape before. Later was found that considerable ad- vantage could derived from the natural rigidity the welded joint and that certain types structures could easily adapted the principles rigid design. Buildings the rigid frame type 32—THE IRON AGE, June 23, 1938 became more and more predominant Germany within the last years. Most these structures are statically indeterminate they are usually the two-hinged frame type and have been found satisfactory not only appearance but also economy. the way from any frontier station Berlin one may find number all- welded railroad station buildings, and Berlin itself one can inspect about dozen them within distance few minutes’ railroad journey from each other. Germany the greatest encourage- ment structural welding has been given the biggest steel consumers, namely the German State Railways. There can doubt that the rail- roads introducing welding such large scale were not interested any particular method erection but the welding build- ings Germany has be- come well-established prac- tice apparent from this in- teresting second article Mr. Bondy. Although most the structures illustrated are for railroad purposes, there has been similar prog- ress factory and office buildings. The previous arti- cle this series, The Age June was devoted research and design. only achieving better technical and economic results welding instead riveting and bolting previously em- ploved. Three Main Types Welded countries different types steel struc- tures are preferred for welding. After number years structural weld- ing these differences are becoming clearly apparent. Generally speaking three main types buildings can Germany, structures consisting mainly rolled steel beams and columns (type are rarely welded. the other hand great numbers them were erected welding other coun- tries, especially the United States, and also quite recently Italy. Con- siderable saving weight and cost claimed for the welded construction but appears that very elaborate de- tails have worked out for erec- tion site make favorably com- types welded build- ings. | | | | ° ° | | i ° | i | AA 7 fi 6 > Germany pare with the simple methods bolting. the second group (b) belong buildings with truss roofs which were often welded especially the early years structural welding practice. But later trusses were found af- ford only limited advantages when welded instead being riveted. There can saving weight with the compression members which comprise the greater portion the total weight. only natural that contractors and consumers alike are attracted the maximum amount saving steel and cost. Structures the rigid frame type shown group (c) belong the favorite types all-welded structures Germany. These rigid frames con- sist either rolled steel sections plate girders varying depth follow- ing closely possible the maxi- mum bending moment Maximum Clear Space Objective present-day practice Germany straight lines and sharp corners steel frames are favored, thus doing Part Rigid Frame Building away with all intermediate supports and unnecessary bracing. With many the biggest welded structures Germany the point view appear- ance was much the foreground. Modern architects are generally favor rigid frame structures which give them much more clear space compared with truss type buildings. regards buildings group (a), American practice has obviously suc- ceeded making the welding these structures paying proposition. Sim- ilar conditions appear prevail with ABOVE 2—Main joint type girder, berg station, Berlin. LEFT IG. 3—Vierendeel span, Duisburg cen- tral station. THE IRON AGE, June 23, 1938—33 Fic. 4—Interior view the Harkort workshops, Duisburg. structural welding Italy, Belgium, etc. the writer’s mind other types buildings, especially those group (c), lend themselves better welding. Although means have been found dispense with bolt holes for erection purposes can hardly expected that assembling methods without bolts will safe and economical. But for this kind structure welding can prove extremely useful doing all the shop work connection with seat angles for beams and columns, espe- cially case irregular and skew joints. Saving also effected fabricating the beams and columns themselves welding instead rivet- ing. Even automatic welding might prove very useful such cases. With buildings the types shown group (a) the main economy which can achieved welding does not much concern the joints but the members themselves. Riveted Trusses Used With Welded Frames With structures the truss type average saving weight and per cent has been effected com- pared with the riveted construction. the German Regulations for Welded Steel Structures! maximum tensile stress the butt weld only per cent allowed compared with that the parent metal. Butt welded joints tension members must therefore provided splice plates carrying per cent the mem- ber force. case compression members per cent the member 4100, August, 1934. 2G. Schaper, Bautechnik, Berlin, February, 1937. July, 34—THE IRON AGE, June 23, 1938 force may transmitted through the butt weld itself while for the remain- ing per cent splice plates are again Owing the above mentioned limits for all-welded trusses was often found economical combine riveted trusses with welded span frame, Harkort, Duisburg. frames the same building. This was the case with freight shed for the German State Railways recently erected Hanover. The roof girders 91-ft. span are welded plate girder design with sky light top. are supported riveted trusses 104-ft. span, carried all-welded Such combinations weld- and riveted portions within the same building are claimed the most economical present under cer- tain conditions. Box-Type Truss Sections Developed New types sections were also in- troduced for welded trusses, for in- stance hollow box type sections which were patented contractor’s firm Leipzig. These sections, mainly rectangular shape, offer the advan- tage great moment inertia. The joints are arranged means pro- jecting gussets and the whole con- struction forms water-tight unit which can easily preserved against corrosion. many cases tubular members have shown considerable advantages with welded number welded structures consisting mainly partly tubular members have been erected the author’s design Ger- many, France and England. Although the price tubes which roughly about twice that rolled steel still prohibitive many cases, tubular members can used compression members welded structures with considerable advantage where special conditions prevail. Railroad Station Structures Welded The third group welded build- ings (c) comprises those consisting | | 3 4 | + 4 4 q q . : 3 = solid web members, either rolled steel sections plate girders, with welded corner joints full strength, thus forming rigid frame. these types buildings are widely applied have found much wider use than the types groups (a) and (b), some notes recent developments may interest. Station roofs the um- brella were erected great num- bers Germany more less standardized design. The vertical up- right restrained concrete block the bottom and the structure all parts exposed bending which 6—70-ft. span frames the Zoo station, Berlin. ° ° ° makes specially suitable for the ap- plication welding. Cross sections rigid frame sta- tions are shown Table The um- brella type structure has been car- ried out great numbers also for suburban stations near Berlin. Fig. shows the top joint such um- brella roof Schéneberg, Berlin. ° ° ° sterwalde course erection (Welding Suppli