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YOUR JOB ENGINEERING COMPANY ECONOMICALLY COMPANY, LIMITED, AKTIEBOLAGET ARBOGA MEKANISK SWEDEN INGLIS COMPANY, LIMITED, TORONTO, i | x J > | OE Editorial Technical Articles Welding Enclosures Speed Work Design Burner Tip for Flame Hardening Cam The Randupson Process Features News and Market Reports 118 Scrap Market and Prices 132 APRIL 24, 1941 Metal Working Activity 119 Construction Steel Comparison Iron and Steel Prices 136 VOL. 147, NO. Summary the Week Ferroalloys, Iron 140 The Industrial Pace Warehouse Prices 141 District Market Reports 124 Sales Possibilities VAN DEVENTER Index Advertisers BAUR Vice-President and General Manager Managing Editor News Editor Technical Editor Machine Associate Editor Editor F. J. WINTERS A. H. DIX, Manager Reader Service Owned and Published by os Art Editor CHILTON COMPANY (Incorporated) Washington Editors Advertising Publication Editorial Resident District Editors Herman, Chilton Bldg., Philadelphio Chestnut and Séth East 42nd T. C. CAMPBELL HERMAN L. KLEIN Hottenstein, 1012 Otis Bldg.., Chicago Pa. New N.Y. Pittsburgh Chicago Leonard, 100 East 42nd New York Peirce Lewis, 7310 Woodward Ave., Ober, 100 East 42nd St., New York Warren, Box 81, Ha…
YOUR JOB ENGINEERING COMPANY ECONOMICALLY COMPANY, LIMITED, AKTIEBOLAGET ARBOGA MEKANISK SWEDEN INGLIS COMPANY, LIMITED, TORONTO, i | x J > | OE Editorial Technical Articles Welding Enclosures Speed Work Design Burner Tip for Flame Hardening Cam The Randupson Process Features News and Market Reports 118 Scrap Market and Prices 132 APRIL 24, 1941 Metal Working Activity 119 Construction Steel Comparison Iron and Steel Prices 136 VOL. 147, NO. Summary the Week Ferroalloys, Iron 140 The Industrial Pace Warehouse Prices 141 District Market Reports 124 Sales Possibilities VAN DEVENTER Index Advertisers BAUR Vice-President and General Manager Managing Editor News Editor Technical Editor Machine Associate Editor Editor F. J. WINTERS A. H. DIX, Manager Reader Service Owned and Published by os Art Editor CHILTON COMPANY (Incorporated) Washington Editors Advertising Publication Editorial Resident District Editors Herman, Chilton Bldg., Philadelphio Chestnut and Séth East 42nd T. C. CAMPBELL HERMAN L. KLEIN Hottenstein, 1012 Otis Bldg.., Chicago Pa. New N.Y. Pittsburgh Chicago Leonard, 100 East 42nd New York Peirce Lewis, 7310 Woodward Ave., Ober, 100 East 42nd St., New York Warren, Box 81, Hartford, Conn. MUSSELMAN, President Editorial Correspondents WwW. P. DEARING ROBERT G. McINTOSH Don F. Harner, 1595 Pacific Avenue, Long JOS. S. HILDRETH, Vice-President Buffalo Beach, Cal. GEORGE GRIFFITHS, Vice-President FRAZAR CHARLES POST EVERIT TERHUNS, Vice-President Boston San Francisco J. H. VAN DEVENTER, Vice-President Milwaukee Birmingham Indexed the Index. BARBER, Treasurer lished every Thursday. Subscription Price: JOHN BLAIR MOFFETT, Secretary United States and Possessions, Mexico, JULIAN CHASE, THOMAS $6.00: Canada, $8.50: Foreign, $12.00 yeor. 4 ny / ; i — i ¥ | — — — » _— f 4 ‘ — | P ee 4 Joseph Ryerson Son, Inc. —through wars, panics, de- pressions and other crises, Industry has come Ryerson for steel. Today, stocks the Ryerson plants America’s great Reservoir Steel— are quite complete, and service general prompt. times like these, however, some sizes certain products are low, few are out. But generally you can depend Ryerson for good service reasonable quantities over 10,000 different kinds, shapes and sizes steel and allied products. you not have the current Ryerson Stock List, gladly send copy. 38—THE IRON AGE, Aprli 24, Steel-Service Plants at: Chicago, St. Louis, Cincinnati, Detroit, Cleveland, Buffalo, Boston, Philadelphia, Jersey City. : — | | j ‘ £ a \ For almost century “ibe ' ' ( APRIL 24, 1941 ESTABLISHED 1855 Ceiling Coffin Lid? SEE the papers,” Mr. Dooley would say, that the boys Washington have put ceiling steel prices and raised the lid coal. Ceiling and lid are two different words, but broadly speaking, they perform the same function. far the man the pine box con- cerned, his ceiling the coffin lid. provides effective stopper further activities, even though perchance the coroner and the doctor had erred and buried him alive. Even when you put ceiling workroom which people are supposed work, you have careful make high enough let them breathe. Otherwise actually becomes coffin lid. And you have take into account that some people require more air than others order keep from suffocating. Some the strong boys even survived the Black Hole Calcutta. The trouble with price ceilings that they are not designed fit the individual. They are supposedly designed fit the average. And averages are very deceptive. Let say that are design ceiling for 100 men whose aver- age height five ft. six. make height five ft. nine, which theoretically would give everybody three inches clearance. But happens, these men are six feet tall and the other half five feet. half them, theory theory, are bound have pains their necks. This theory averages just fallacious setting price ceilings. every industry, steel notably included, the efficiency production varies throughout the industry. There will some low cost producers the top, some high cost producers the bottom and varying strata between. two are exactly matched, due differences loca- tion, managerial talent, their command capital, degree mechanization and volume. rule, rule there be, you can take that the larger units industry are most favorably placed from the cost production stand- point. The smaller ones are the boys who are usually “out limb.” Many these weaker and smaller units are performing valuable service. Some them make specialties that are not made the big companies. None them have turned excessive profits even before the wage rise. And all them are going have their necks,” worse, under this new steel price ceiling. want drive these smaller units out business and make the larger units still larger, this the way it. But not what would call the “American” way. After all, America big hearted country. are willing finance, arm and feed most the nations the world cost billions. Why starve our smaller steel producers home? | | | | AN Thousands tons raw materials are accurately weighed each day When 7,840 Ton Large Quantities Raw Materials Carefully Selected and Blended Required Produce Ton Inland Quality Steel Every ton steel produced the Inland Mills requires 7,840 pounds—nearly lected ore, pure limestone and metallurgical coke. Multiply these requirements 9,000, average day’s steel output, and you have idea the enormous quantities raw materials used making Inland Quality Steel. Long before raw materials are transported the mill, they are carefully analyzed and blended experts Inland owned mines and quarries. SHEETS STRIP TIN PLATE BARS RAILS PLATES TRACK ACCESSORIES Throughout the shipping season, huge piles these materials are accumulated the plant docks. From these piles, Inland metallurgists determine, check analyses, the grades and proportions used. Predetermined blends and formulae then are closely followed accurately weighing every pound material fed the furnaces. Careful control begins with the selection and blending raw materials—and continues throughout the entire Inland steelmaking process. FLOOR PLATES REINFORCING BARS STRUCTURALS PILING ° ° ° DENISON Fulton Foundry Machine Co., Inc. routine laboratory test steels that are hardened, the Jominy test has been help- ful determining the hardening characteristics tool steels, thus enabling the selection the cor- rect steel from both cost and op- erating standpoints. The test has been successful that applica- tion that was decided run some tests Meehanite determine the best types for various applica- tions which required heat treated Meehanite. The Jominy test based the principle “end quenching,” wherby sample in. diameter and 234 in. long quenched striking with stream water the lower end when the speci- men set vertically. This will pro- duce rapid cooling the side near the lower end with progressively slower rates cooling increas- ing distances measured along the side away from the lower end. Con- sequently, the reaction rate fast, high hardness will exist only near the lower end, but the re- action rate the material slower this high hardness will prevail greater and greater distances away from this lower end against which ominy Test Meehanite —Originally employed determine the hard- ening characteristics tool steels, the Jominy test now being experimentally used ascer- tain the best type heat treated Meehanite for various applications. This article describes the tests and the results obtained. the water projected. matter standardization the water velocity which will raise the water fountain in. high. The specimen held rigidly the center this fountain in. above the water outlet. The temperature the water approximates deg. The apparatus consists water tank rigged with motor driven pump with piping and valves for controlling the flow water, and over the top the tank con- structed fixture for holding the specimen for quenching, trated the picture the machine (Fig. 1), with the test specimen place. the machine (Fig. 2), which was built the Fulton Foundry Machine Co., Inc., gives details the apparatus. was suggested that few pre- liminary hardenability tests Jominy apparatus tried, and this was done. Knowing the effect manganese delaying reaction rates and bearing mind that “GM” Meehanite finding exten- sive application the heavier cast- ings subjected severe and ex- cessive stresses particularly they are heat treated, was de- cided run tests both and “GM” Meehanite for comparative purposes. Fig. was developed from these preliminary tests. These curves show few interesting things: (1) Curves for specimen 1.21 per cent manganese and 0.85 per cent manganese are about the same even though the silicon content the 1.21 per cent manganese speci- men considerably lower than the other specimens, which was al- ways thought should react favor- ably help hardenability. (2) Even though the silicon high the specimen with 1.60 per cent manganese showed tremend- ously improved hardenability reac- tion. This very significant and should remembered when con- sidering other curves presented this paper. other researches the relation cooling rates bars various diameters, compared with the cooling rate Jominy specimen varying distances from the quenched lower end, been worked out the investigators sponsoring these tests. This creates practical aspect for these Jominy THE IRON AGE, April 24, | 4 ° ° | lay ay 4 | > “9 S. | Spring plunger ---- locate and hold specimen hold for quenching RIGHT IG. 2—Test piece set-up the elec- tric furnace. The tub- ing put around the specimen pro- Screw fixture Round test piece long screwed info specimen Pump motor Pipe through which IG. testing machine used these ex- periments. This equipment was built Fulton Foundry Machine Inc. tect from atmos- pheric conditions. Also, the graphite flake pack, small tray and carbon block the bottom seals the specimen against entrance air. Meehanite specimen Face tobe Graphite pack tray -Carbon block Still v > + So a0 Oo he v a 3 \4 2 24 Distance from water-cooled end, inches 4—Relation cooling rates bars various diameters, com- pared with the cooling rate the Jom- iny specimen varying distances from the quenched lower end. hardness Rockwell preliminary hardenability tests. Each the three speci- mens was heated for hr. 1600 deg. 42—THE IRON AGE, April 24, 1941 | te i ' | Ac = | | | | ° ° ° 4 | | Distance from water cooled end, inches and the curves are given Fig. interpretation use the curves shown Figs. and would follows: Suppose specimen in. diameter oil quench being shows the cooling rate the specimen the same in. from the quenched end the Jom- iny test bar, that referring apparent that in. from the end gives hardness over Rock- well all three samples. There- fore, the piece will harden nicely. But following through specimen, apparent that the cooling equivalent in. oil quench, that the lower manganese specimens the quench will produce only about Rock- well hardness while the high 1.60 per cent manganese specimen possible get over Rock- well hardness. This shows practical value these curves for hardness cycle de- termination, because this same 2-in. specimen has cooling equivalent water quench in. from the quenched end the Jominy bar which then would give satis- factory hardness all three speci- mens with the three different man- ganese contents, shown the curves Fig. Thus, there hardenability relation both from composition (with variations manganese being primary im- portance) and speed quench (whether water oil), and this tive data basis. might also mentioned that possible reflect back past work the Fulton Foundry Machine Co. and find that practical experiences quenching and heat treatment have just about checked with the findings shown these curves. This also the necessity use good judgment with time quenching and variations sults. This was thought strange the time, but the results would have been properly expected equivalents disclosed these tests and curves been known. With these preliminary results showing interestingly, was decided enlarge the research and try determine: (1) The effect quenching tem- perature hardenability. (2) The effect soaking time sensitivity hardenability. oO + | | min.at 1580°F “ + Distance from quenched end, inches IG. 5—Five series tests were made Meehanite different compositions and the curves all have the same trend. They show, rea- sonable soaking was not harmful, (2) with manganese high reasonable soak was desirable get good austinite for quenching, (3) 1580 deg. would good quenching temperature use generally the remainder the research. x Distance from quenched end, inches IG. 6—This (1.24 Mn) Meehanite about normal. Here shown quenched from 1580 deg. after and 30-min. soaks. These results appear satisfactory, and the same cycle used for other curves covering other specimens. scale Rockwell Distance from quenched end, inches 7—Four specimens Meehanite tested, each soaked for min. 1580 deg. The manganese percentages here are fairly close. (3) The effect composition variations hardenability. treatment hardenability. (5) Anything else that might disclosed while running these tests. For this work, number spe- cial samples were poured, and also eleven others were obtained from various Meehanite foundries. series specimens was run quench from 1525 deg. 1580 deg. F., and 1625 deg. F., and soak- ing periods varying from min. THE IRON AGE, April 24, | | | ~ | | | . | ~ | - | = = ” Distance from quenched end, inches four types Meehanite, the manganese percentages being different from those Fig. 30-min. soak 1580 deg. was used. VU W) | Distance from quenched end,inches 9—Jominy test Meehanite with higher manganese content. Figs. and 30-min. soak 1580 deg. was used scale 0.75 Rockwell Distance from quenched hes test Meehanite with lower range manganese. other tests, 30-min. soak 1580 deg. was used. hr. were used the intermediate 1580 deg. temperature, all with the idea getting some light the importance temperature and soaking time factor this research. The curves Figs. and are self explanatory. The curves shown Figs. and take only small practical range temperature soak. get really extended data would re- quire further research beyond the scope this preliminary in- vestigation. This may done later. But the tests made indicated Meehanite suitable for normal heat 44—THE IRON AGE, April 24, 1941 treatment not unduly sensitive breakdown reasonable soaking periods and not nearly sensitive many other irons. Therefore, for the balance this investiga- tion, was determined use 30- min. soak periods 1580 deg. and, where permissible, check this with 3-min. soak periods the same temperature. this investigation constitutes the first work this kind, were not able cover this subject completely and intend continue investigations along this line using new equipment and many new spec- imens. However, the specimens lected for this research had many analytical variations, and some pre- liminary trends could mined grouping them and plot- ting Jominy curves and analyzing these hardenability curves. For this check the Jominy curves made specimens soaked min. 1580 deg. are used, and the tests indicated that man- ganese was apparently the element requiring control, four curves are grouped together sets where the manganese percentage was closely the same. Sixteen specimens are covered this series. See the and 10. There difficulty drawing definite conclusions curves because most cases more than one factor influencing them, but some trends are evident: (1) There not much differ- ence between the curves Fig. and Fig. 10. Then, too, some in- stances there not much difference total carbon, manganese, and Meehanite treatment. But the sili- con analysis varies quite widely from 1.0 per cent 1.7 per cent, which would indicate that least the lower ranges the percentage silicon has not much effect the reaction rate influence hard- enability. (2) Again, observing the groups noted that some specimens are “GA” Meehanite and “GB” Meehanite, vet the Jominy hardenability curves are about the same. This would indicate that general there little any differ- ence the hardenability properties “GA” Meehanite and “GB” Meehanite providing “GB” made specified Meehanite instruc- tions. (3) Fig. shows high man- ganese series, and takes only glance see that manganese potent element delay the reac- tion rate and ability. Also, that while increased percentages manganese probably ability yet practical percentage seems around 1.50 per cent, which reference the curve for cooling equivalents would give good about in. sections and water quench in. in. sections. Likewise, when considered how very potent manganese delay- ing the reaction rate would seem that chromium here had t . | | | m 4 | >» | | effect and may not effective believed that better use manganese than chromium duce hardenability because also produces tougher and more machin- able castings. other words, believed that these curves favor manganese rather than chromium hardener when considered from every standpoint. However, there doubtless room for more investigation the effect chro- mium, especially for heavier section work where moderate percentages not harm the pearlitic structure Meehanite. The plan check this further investigation. From the various charts which have been shown this paper, readily concluded that with- certain limits silicon content has very little effect the hard- ening qualities Meehanite. Also total carbon, within certain ranges, has little effect the reaction rates scale Rockwell Distance from quenched end,inches curves for improved Meehanite, made the plant Fulton Foundry Machine the result this research. cooling. greatly affects the reaction rates, and light section castings are though the castings contain only the normal amounts manganese. casting has exceedingly heavy Determining Nitrogen Content has been observed that con- siderable differences frequently occur the nitrogen determina- tions the same steel when ried out different laboratories, Treje, Jernkontorets Annaler. 1940, vol. 124, No. According translation the Iron and Steel Institute (British). the authors have, therefore, inves- tigated the accuracy number different methods, and they sur- vey the literature the subject and report some the results Preventing causes the formation cracks steel, with particular reference the investi- gation the failure the shell plate the upper dome marine boiler, were discussed Wall- gren Teknisk Tidskrift (Swed- ish), 1940, vol. 70, Oct. 19. According translation the Iron and Steel Institute (British), the author differentiates between fatigue cracks without corrosion, inter-crystalline cracks caused caustic embrittlement, and corro- sion-fatigue cracks. Specimens the boiler plate taken tions close to, and away from, the obtained their laboratory work. Determinations can easily made with unalloyed steels dissolving the sample dilute acid which converts the nitrogen into am- monium salt; but with alloy steels difficulties arise owing nitrogen being retained the undissolved residue. number methods treating the residue were examined. These included filtering as- bestos, drying about 100 deg. C., and dissolving the residue either sulphuric acid with sulphate addition, perchloric acid with cracks and etched Fry’s method revealed slip lines angles about deg. the surface the plate. The cracks were, however, deg. the surface. The cracks passed partly along grain boun- daries and partly grains. discussing whether stress the primary cause crack forma- tion boiler plate, the author states that this the case only when the slip lines are marked have been caused stresses the elastic limit the steel. the opinion that corrosion- sections and desired have high hardness penetration value these sections, will necessary retard the reaction rates accord- ingly. The results such ad- justment are shown Fig. 11. Alloys addition sulphuric acid, alternatively oxidation with method. The authors found that most cases the results were fairly good agreement. their opinion the method using sulphuric acid with sulphate addition simple and reliable one. comprehensive table, which the nitrogen deter- minations for large number alloy steels are compared, pre- sented, and bibliography ap- pended. Corrosion Cracks Boiler Steel fatigue cracks can also form and grow regions where there are slip lines but are high stresses less than the elastic limit. steel can cold worked without any slip lines appearing and such region very sensitive cor- rosion. Another point which sup- ports the theory that slip lines are not the primary cause corrosion cracks the fact that those parts boiler which are cold worked during erection the extent that slip lines occur, but which are not heavily stressed when the boiler pressure, have tendency the formation corrosion cracks. THE IRON AGE, April 24, 1941—45 | 4 50 com — Wy + | ~ ‘NG, | ~ | | 4 | 77, IG. pitch (left) flexible metal hose; and normal pitch (right) flexible metal hose. IG. 2—Seamless monel metal tubing almost flexible rubber tubing. monel metal tubing, as-received (left) and as-drawn (right). IRON AGE, April 24, 1941 Tubing metallurgy the steels used, the draw- ing and corrugating equipment employed, etc. ° METZLER Metallurgist, Eclipse Aviation Division, Bendix Aviation Corp. metal hose combines the characteristics metal with the flexibility rubber. The type metal hose discussed this article made from thin- walled seamless metal tubing.* the East Orange, J., plant the Eclipse Aviation Division, Bendix Aviation Corp., metal hose produced six non- ferrous and two These alloys include per cent sili- con bronze, 85-15 brass, 70-30 cupro-nickel, pure silver, monel metal, aluminum, nickel, stainless steel and low-car- bon steel. The seamless tubing formed into flexible hose sizes ranging from in. in. inside diam- eter. Larger sizes are available spirally corrugated, heavy walled hose for applications where the flexibility, large degree, sac- rificed for high strength. The flexible hose can furnished two forms, namely, close and normal pitch (see Fig. 1). For high strength and medium flexibil- ity thin wall material the close pitch hose used. Where high flexibility and average strength required the normal pitch hose specified. For production stainless steel flex- ible hose from welded tubing, see The Tron Age, Aug. 17, 1939, 46-48. ° produce hose made from metal which has some the attri- butes rubber (Fig. 2), close metallurgical supervision neces- sary. Rigid specifications covering the purchase the raw material have been drawn the metal- lurgical department cooperation with the production department. chemical composition ranges, size tolerances, surface finish require- ments and definite grain size the as-received condition. The last mentioned item the most impor- tant one all from standpoint. Each shipment raw material inspected checked for dimensions and sam- pled for metallurgical examination. must pass each and all these examinations and its failure any one would cause rejection. The raw tubing which has passed these tests drawn cold, one pass, approximately one-third its original wall thickness and three-fourths its original diam- eter. Since the tubing given this drastic draw, the reason for the close inspection the raw ma- terial quite obvious, any slight seam hair line the raw tub- ing will drawn three four times its original length. Since the drawn tube the wall thickness 6 3 | ° Fg greatly reduced, the seams hairlines may cause faulty tube either split during the drawing operation else result fin- ished product with undesirable weakness. The effect this cold drawing operation the original grain size may seen the photo- micrographs the raw and drawn tubing (Fig. 3). The drawing operation formed draw bench which has me j machine, showing the four forward fingers which hold the tube while the loop formed the rear fingers. IG. 5—Microstructure silicon bronze (left) and monel metal (right) hose after drawing and re- annealing. rotating steel balls the die head instead the solid type die head. beveled, plug type mandrel used aid the balls performing the drawing operation. While the mandrel maintaining the inside dimension, the rotating balls, oper- ating high speed, work the wall and outside diameters the fin- ished dimensions. Although the operation resembles swaging, the drawn tube has smooth, even, and bright surface finish. matically operated bench, which requires only the insertion the tube, pulls the raw tube through the drawing head. Upon completion the draw length the raw tubing, mechanism releases itself, and the drawn tube deposited trough alongside the bench. this type drawing, water soluble drawing compound was — 7—Washing machine, showing two tanks. One tank contains solvent and the other contains boiling water. The drum revolved mechanically each tank turn. found give the best results. the other hand, the corrugating op- eration which less drastic cold working process, requires extra heavy machine oil lubricant. make this drawn tubing suit- able for the corrugating operation recrystallizing anneal neces- sary. This annealing operation accomplished Hayes bright annealing conveyor furnace (see Fig. 4). Each length tubing must annealed this controlled atmosphere the drawn tubing must free scale for the next operation. order attain the scale-free surface condition, series gas atmos- pheres was developed for each dif- ferent These atmospheres are produced cracking city gas the presence air and intro- ducing the product into the heating chamber the furnace. The natural air excluded from the open conveyor door flame cur- tain. Various alloys, course, re- quire different temperatures and times temperature. These vari- ables had put ratio with the controlled atmosphere order 48—THE IRON AGE, April 24, obtain the best surface finish. The results the annealing are shown the photomicrographs (Fig. 5). The corrugating operation entirely automatic. annealed length tubing placed the machine one end and each set forming fingers moves the ma- terial forward producing the fin- ished product the opposite end. The fingers are arranged two sets, one, the gripping and holding set, and the other, the forming set. Since the corrugation itself ac- tually easy loop, the rear set fingers pushes forward while the front set holds and the loop formed. This operation reduces the length the tube approxi- mately per cent, namely, four one ratio. view this machine properly annealed tubing the above operation readily per- formed and only small amount cold work strain introduced. This strain subsequently relieved low temperature anneal the bright annealing atmosphere control furnace. There change grain size the corrugating operation and therefore change need obtained the light an- neal. The grain size the tubing af- fects the corrugating operation, only from the hardness the metal. perform this operation the grain size most materials may low 0.025 mm. minimum without caus- ing any difficulty forming the corrugations. For monel metal, nickel, stainless steel high work-hardening grain size must kept above trouble will develop. the metal too hard form, the fingers will not complete the operation, ing, instead round tube, one with hexagonal inside diameter. This condition serves warning and helps preserve tool life since continued operation using the hard material will show considerable tool wear which produces able surface finish the hose. The presence heat treating scale the tubing will cause the same tool wear with its resulting poor sur- face finish. This one the main advantages the controlled atmos- phere furnace. For the fingers actual work- ing tools, nitrided high speed steel used where the softer alloys are worked. Monel metal, nickel and stainless steel, however, require chromium plated hardened tool steel fingers both for wear re- sistance and for low coefficient friction. All grades the corrugated ma- terial are then washed the ro- tary washer shown Fig. This washer consists rinse sol- vent remove the heavy grease and then boiling hot water rinse remove the solvent. Each length flexible hose then tested with air hydraulic pressure detect any small pin holes defects which may have opened during the drawing corrugating. pass this inspection the tubing must withstand pressure 1000 per sq. in. The larger sizes thin walled flexible hose are often used the inner portion water jacketed ex- haust connections. Frequently these connectors are covered with protective braid which brazed the outer portion the con- nector nipple. This braid affords additional protection and increases the flexing strength the com- pleted product. Special stress relief annealing treatments are given hose dampen vibration. This special type anneal was de- veloped primarily for hose used air conditioning units where the vibration frequency was high but where the resulting noise must eliminated. Special applications hose are too numerous mention detail. However, other applica- tions addition those already mentioned include: carrying oil for hydraulic systems under high pres- sure, carrying lubricating oil Tin Hats Require Many Operations simple lines the finished “tin derby” the style used the United States and British armies (see accompanying illustra- tion, courtesy Modern Industrial Press), belie the many volved which, from steel stock final wearing, consist blanking, drawing, annealing followed stamping, trimming and the edging operation which in- cludes spot welding; then, the piercing small vent the dome for ventilation; the attaching spring clips, painting ing. The few final steps are fitting the helmet with sweat band and chin strap. Naturally, the more elaborate helmets favored some countries, with deep crowns and hemmed rims, require several ad- ditional redrawing, restamping and annealing operations, according the Vanadium Corp. America. While the chief purpose the trench helmet the obvious one protecting the wearer’s head against bullets and shell fragments, equally important that army the field corps fire- men chasing incendiary not burdened with helmet that inconvenient wear regardless moving machinery parts, carrying high pressure steam and corrosive chemicals, connections vibrations, oil burner feed lines, and forth. The individual alloys, however, have their own particular field usefulness. Silicon bronze widely used for oil burner connections and for conducting Freon and other re- frigerants. Flexible tubing made from monel metal used for high pressure, superheated steam, corro- sive chemicals and where strength controlling factor. Aviation applications create the largest de- mand for the aluminum alloy hose major consideration. Saturated steam under pressures 250 per sq. in. may carried hose made 85-15 brass. Although flexible hose produced from wide range ma- terials, individual applications fre- quently Therefore, while they may not regular production item, alloys mentioned are made the cus- tomer’s requirements. For transporting most liquids, vapors semi-solids, most likely that there alloy and connection which can made flexible metal tubing. —— 6 TRANSVERSE SECTION IN \ EDGING 0.022 THICK LONGITUDINAL SECTION the season—in rain, snow beneath hot summer sun. That’s why military authorities have emphasized the need for relatively light helmet weighing be- tween lb. oz. and oz. Yet the material from which made must strong and tough enough not. break split under the impact shell fragment re- turning earth nearly fast the original shell left the gun bar- rel. The following table lists the chemical composition some steels which have been used various armies: Composition No.1 No. No. Molybdenum 0.35 Before the finished mets are issued the wearers, thorough test usually required. Samples chosen random from lot are subjected severe firing tests which are equivalent the punishment encountered under fire. THE IRON AGE, April 24, 1941—49 . | i { ) | | | | | > | IN lf | / \ | } 4 + = / = -—+ | Wz | 4 4 WA / / / \ \ — | { ABOVE PECIALLY de- signed high- speed power presses, automatically fed, and forming 600 special nuts per min- ute. Attached the side the press specially designed roller and grip-type feeder. advance this the loop drawn bar stock passing through the upraised control arm that controls the feeding the automatic straightener. The straightener supplied from coil material shown the back- ground. The material straightened both horizontal and vertical planes, and over- feeds the mechanical feeder and press provide against any dragging tension that would interfere with accuracy the press cut-off. ° ABOVE automatic tappers put the finish- ing operation the nut. Each tapper equipped with rotary hopper, belt- driven individual electric motors. These hoppers, designed the users, are in- corporated special swaging machines presses for installing the nuts. ° ° ° RIGHT automobile door striker plate requiring the installation four nuts shown here after removal from the swaging oper- ation. Four rotary hoppers feed Fabristee! nuts through semi-closed channels position the anvil. The operator piaces the striker plate stamping position for swaging blow. t from coils steel stock con- tinuous, automatic methods three-stage progressive dies the rate 600 per min. being accom- plished FabriSteel Products, Inc., Detroit. with three production units, turning out excess three-quarter mil- lion special nuts every 8-hr. day. The product the Fast-On lock (clinch) nut used widely for sheet metal assembly. Its appearance rectangular nut. made from flanged section, cold drawn SAE 1112 steel. Manufacturing equipment spe- cial nature—from the automatic straighteners with automatic ten- sioning control, through the me- chanical feeder, the dies, and the ultra high speed power presses. Three such presses operate con- junction with battery auto- matic tappers equipped with rotary SHERMAN Detroit Editor, The Age —Clinch nuts for rapid sheet metal assembly made continuously from cold drawn steel the rate 750,000 per 8-hr. day hoppers and special tools designed the user. Each automatic straightener in- cludes both horizontal and vertical sets rolls, necessary because the rapid press action requires accurate, smooth feed. straightener over-feeds its press slightly, the mechanical feeder does not have excessively hard. This avoids iraccuracies feeding, and con- t-ibutes accuracy the finished nut, which held within 0.003-in. tolerance cut-off length. feeding the straightener con- trolled long hooked arm which carried the loop excess material between the rollers and the press; when the loop reaches predetermined height, the arm trips mercury switch, stopping the straightener until more ma- terial needed. The mechanical feeder, built FabriSteel specifications, mount- the press and slides forward small (square) portion the nut inserted punched square hole, protruding just enough for the four corners clinched with swaging tool. enough material for two nuts each stroke the press. This feed accurate, control the width each nut, and synchronized with the fast-acting press. The die simple, without spring- moveable parts; actually little more than holder and guide for the material, and anvil. This sim- plicity probably the main reason for its success under the high-speed piercing and cut off blows from the press. However, the progressive die action unusual that per- mits piercing and cutting off pairs nuts simultaneously every stroke the press, after the initial ones, effective and two nuts are produced once. After cut off, the nuts drop down chutes containers below the press. The velocity the out-com- ing nuts great that they would rebound the ceiling the press room, except that the chutes are baffled. The presses, two 25-ton and one are type that ordinarily run approximately 100 strokes per min. These are specially de- signed operate 500 strokes per min., actually perform 300 day and day out. Somewhat heavier than conventional equipment, and equipped with special bearings and pressure lubrication system, they are built with heavy duty disk type clutch controlled electrically. Various methods these clinch nuts are employed, de- pending upon production require- ments—ranging from hand swag- ing the use automatic ma- chine equipment. (See accompany- ing photographs. THE IRON AGE, April 24, | 4 | ) | \ | | | | | | | ‘ ‘ Economic Factors must kept mind that structural welding, where weld- ing done both shop and field, many factors enter into the cost and that, therefore, the econ- omy welded construction de- pends not only the process itself but upon the methods fabrica- tion, handling shop and field; these turn depending equip- ment and personnel available. Just riveted construction, shop equipped with spacers, edge planers, gang drills, etc., and with force men accustomed use those machines effectively will use different methods fabrication from another structural shop equipped only with shears, single punches and drills and rudimen- shop well equipped with transfer cranes, with jibs gentries handle and turn the work over and with personnel experienced arc welding and automobile flame-cut- ting will handle work quite differ- ently from shop less completely equipped and obliged expand its welding staff every time faces job above average size. One shop, for example, will plates with shear while another one cuts them with flame-cutter: one shop will true the edge web bear tight under cover plate above angles riveted construction, unless the edge the web plate sheared (upper), set back from the flange plate (lower). 52—THE IRON AGE, April 24, plates with edge planer while another will use fillet weld and grinder bring the edges flush after assembly with the top bot- tom flange angles. Fig. shows section through riveted girder which de- sired that the web bear intimately against the top cover plate. This girder may building girder carrying very heavy distributed load several columns; may railroad deck girder. real- ized, course, that sheared plate edges are not true enough give solid, dependable bearing edge. consequence, riveted prac- tice, such plates are set back from the back the flange angles il- lustrated for the bottom shop with edge planer may elect set one edge the web plate against the planer and machine true. Then the girder will as- sembled upside down (Fig. 2), with the top flange the shop floor and the machined edge the web bearing the flange plate. The angles, first assembled the web, will now tack-welded the flange, after which the assembly will taken the riveters. Another shop will accomplish the same result assembling the top Bottom flange Tack weld Top flange on.cover plate 2—Procedure assembling the machined edge web plate with the flange angles and plate. flange angles the flange 3), riveting them together, then welding the gap between the back the angles and grinding the top the weld flush with the back the angles after which the top flange plate will assembled the angles the usual way. are only few spots the length the girder where bearing the web against the under side the top flange plate necessary—such under columns resting the planing the full length the web. Similarly, only few girders are involved, would likely cheaper use welding and grinding than work. follows that cost comparisons between various means and ods fabrication depend upon the set-up the individual shop. making cost comparisons, plant op- erators should themselves familiar with all the advantages welding because this process does furnish means cutting fabrication costs countless cases. since there are right ways and wrong ways welding structural shapes, and the fact that design and grind Top flange IS. construction where sheared universal plate used. » ¥ > £ | 4 | & £ | E t | 4 | ‘ ' | & and shop drawings and often with- out full information throws off cost estimates. common experience among fabricators, for example, receive framing indicate girders, columns, beams, etc., ac- companied such note this one: “Girders may welded.” “Column details are are Nothing definite indi- cated regarding the size and the amount welding desired. evident that when the estimators price the job, they must play The possible welding that might demanded the designer as- sumed—not the amount that ac- tually needed. Later on, the gird- ers columns will detailed with the correct welding, but even the designers accept the details made, the cost the owner the structure will still that figured into the job the estimators. The point made here not that every piece should detailed the designers (details should made the detailers), but the de- signers should indicate clearly notes the drawings and suit- able items their specifications what type welding they will ex- pect, what they will require for girder welding, for columns and (a) (b) LANDIS Chief Engineer, Lincoln Cleveland for column connections. Items recurring numbers should plainly shown the drawings. common detail received the load not indicated; neither the position nor the size fillet. The shop may weld the angle shown right way, d—but any case, the angle has been welded called for takes very little time actually show what really required. Another detail often received the shops shown Fig. The column may 8-in. with sole plate in. thick 14-in. column with base slab in. thick, but the detailer’s note the same: “Weld.” there any excuse for such note the case light column and base, there none the case heavy ones. the lat- ter construction, there usually considerable disparity between the thickness the column section and (c) (d) number methods (b, and being used fabricating welding, tending upset original cost estimates and result unsatistactory job. that the slab base. such de- signs, the welding requires special care and should shown clearly the shop details. Fig. note that the arrows point both the flange and the web. will observed that base plates in. thick less are not usually milled, that there possibility poor bearing the web the base; consequently the conditions may warrant that the web welded the base. Bases heavier than in. are milled and the bearing the column web the plate therefore positive. There good reason such cases weld the web the base. Even there bending the column either direction the welds connecting the flanges the base would have torn off before appreciable stress could developed the welds connect- ing the web the base plate. important point bear mind when designing welded struc- tures keep the amount welding the required economical not prime importance keep the number holes and rivets down the figured minimum. For example, Fig. shows tension angle connected single rivet IG. 5—Where heavy base plates are milled, assuring good column bearing, there necessity weld the web section H-column that base. THE IRON AGE, April 24, | | | 4 | | | | { | j ° ° | | 4 | | it il i! Seat ' 5 | | } it GS i j ' , . | riveted tension angles, there waste detailing three rivets where one will carry the load. The effective section the angle across section de- creased the diameter the hole. the same angle connected three rivets. The loss sec- tion greater than since the three holes are line and other. consequence, rivet- work, the custom exists de- tailing connections for the full length the member connected, whether this needed not. There particularly good reason for the practice and should not applied welded work. While there the excuse riveted work that costs more punch three holes than punch one, does cost more drive three rivets than drive one—and certainly costs more lay down in. 5/16-in. fillet than lay down three times much. designing welded structures, the welding should the stresses, not the material; i.e., the stress should dictate the size the welds. Riveted work has developed its methods and practices from its own inherent nature. Welding has its own peculiarities and should logi- cally establish practices that are line with these peculiarities. not just matter copying rivet- ing practices. Consider, for instance, girder 54—THE IRON AGE, April 24, stiffeners. riveted girder bear- ing stiffener needs filler plate make for the thickness the angles against the web, shown shown such fillers are need- because there are angles. the top the stiffener not welded the flange. angle, one leg which parallel the girder’s web and this leg may not counted upon trans- mit concentrated load the girder web according bridge specifications and others. With the welded construction, the other hand, ail the stiffener Bearing stiffener Angle stiffeners Plate and flange pendicular the web and since directly connected the flange, all may counted upon for transmitting load the web. The fact that the plate stiffener ends the flanges makes col- umn fully fixed the ends. Ad- vantage should taken this condition designing welded stif- feners. the riveted construction the usual set-back the web plate forms gap which prevents direct transmission stress the web plate. such gap exists: Consequently, least portion any concentrated load taken di- rectly into the web. That much carried the stiffeners; this ac- counts for further reduction material. Non-bearing stiffeners rivet- girder, such shown Fig. must attached the web. welded girder, the ends all stiffeners should welded the flanges (Fig. 7b), square the girder and hold place during the subsequent welding. quently very little welding such non-bearing stiffeners the girder web needed since their only tion hold alinement the web which they straddle. Nevertheless, many welded girder drawing comes the shop showing non- bearing stiffeners the girder web—a distinct waste time and material. the shops, many welder and many inspector prides himself “turning out good job” overwelding. The fillet speci- fied turns out full in.; the two-pass fillet called for the drawings gages almost in. and the shop will draw the en- gineer’s attention the fact that “he’s getting his money’s worth and then some.” Now, has been IG. 7—Riveted and welded Bearing construction each stiffener calls for its own methods and practices. These two views show how plate stiffen- ers are applied. BELOW IG. 8—Typical non bearing riveted angle stiffeners. Web stiffener Loose fillers Angle stiffeners ---- Plate and Flange this engineer’s business make allowances for the human element, for shrinkage and for all such fac- tors well for the calculated stresses the connections the time was designing the job. Con- sequently, the shop should not feel that incumbent upon add welding that shown his draw- ings. would indicate that the shop does not feel very confident the engineer’s proficiency de- signing the welding the value its own work. Overwelding should not encouraged. at a . AO Lana i) oS (a) (b) q q | Hot Cast lron important data available June, 1940, the ever-growing practice tinning cast irons. Includes cleaning instructions, detailed data fluxing and hot-dip tinning, and tinning wiping. difficulty tinning cast lies preparing clean metallic surface, for the pres- ence graphite any other non- metallic constituent prevents ad- herence the tin. The different methods procedure employed preparing castings solely this end, according the Bureau Technical Information, International Tin Research and De- velopment Council. Since, all cases, the outer skin must removed from the casting, pattern design and foundry practice facilitate this operation. Thus the outlines the casting should smooth possible, re- entrant angles and projecting cor- ners being well filleted, and the iron should comparatively soft. Little scrap should used the melt, and the contents carbon and manganese should below per cent and 0.5 per cent, respectively, with sulphur low possible. Dry sand castings are preferable green sand castings account their better surface, and order avoid the produc- tion tough skin, patent core binders containing resin should not dispense with the use coal dust the sand blackleading the mold, except the case very heavy castings, where there dan- ger sand fusion. Naturally, when castings are treated one the malleable iron processes, the initial hardness toughness the outer layer not important, the treatment produces softening. The above remarks apply whether tinning carried out hot- dipping, wiping, electrodeposi- tion, but the procedure for treat- ing the castings after manufacture differs according the tinning process employed, these processes will considered separately. Hot Dipping Preparation the casting for hot dipping follows: Decarbonization: Since the graphite the iron one the main sources difficulty, number recommend pre- liminary heating gray iron cast- ings decarbonize the surface layer. This procedure, which in- tended mainly for heavy castings, consists heating them red heat for hr., boxes packed with haematite, other oxide iron manganese. This treatment not recommended universally and states that tends make the subsequent tinning un- even. Cleaning the surface: Clean- ing follows the same general lines, whether decarbonization has been carried out not, although wide range methods procedure advocated Broadly, there are two methods removing the outer skin from casting—chemical and mechanical. The chemical method consists pickling acid, and the mechanical process may machining, sand- blasting, tumbling. Since any these processes may reasonably effective, every manufacturer has his own ideas which method combination methods best. and consider that preferable use mechanical means only. Schott’ recommends tumbling with basalt however, favors sandblasting, while considers the treat- ments equally satisfactory. Marnach’ and state that the best results are obtained sandblasting followed pick- ling for short time, although suggests this for heavy castings only. According Nightingale, the surfaces cast- ings, which have not been sand- blasted, are liable retain particles molding sand embedded de- pressions, even after the articles have been pickled. Others consider that pickling may successfully employed without preliminary sand- blastin