The Iron Age 1943-06-17: Vol 151 Iss 24

fast 17, 1943 JUN 1943 300 feet “Lightning” that knows how strike! Boat what the Navy calls her! Destroyer Escort —300 feet built dish out what takes make Axis wish they had stayed home. Slim, sleek, and deadly, the D-E’s are pro- pelled Diesel engines and manned crews who know how the job assigned them. Many the Diesels for Destroyer Escorts and other Navy warships are Fairbanks- Morse manufacture. The skill, facilities, and engineering experience that have given airbanks-Morse Diesels world-wide reputa- tion for dependability are now used provide dependable power for Navy craft when dependability important. Fairbanks, Morse Co.,600 Michigan Ave., Chicago, FAIRBANKS, MORSE CO. — | | | ; a : 4 * 4 | = into huddle, and generally emerge with pretty good idea—for your own specific design that results light weight, good strength, and long life. also make carburizing boxes that are giving fine service under hard use. The above fixtures are used pit-type carburizing furnace, that handles ball bearing races. The temperature 1700° F., followed oil quench the fixture and its 2000 3400 load. The fixture weighs 225 Its design our own and overcame trouble experienced with heavier fixture designed elsewhere. Its successful behavior proven the repeat orders. This carrier made our Alloy-502 (35-15), cast and rolled material, which melted high frequency induction. make good heat-resistant alloys and provide good sound design for their fabrication. think can help you—write us. Hoskins Manufacturing Company, Detroit, Michigan. ‘CTRIC HEAT TREATING URNAC 4 LEMENT ALLOY THERMOCOUPL' LEAD WIRE NELDING al STANT CASTING: THE IRON AGE, published every Thursday the CHILTON CO. (INC.). Entered second class matter November 1932, the Post Office Philadelphia under act March 1879. yearly North America and South America, Foreign $15, Vol. 151, No. 24. Office VAN DEVENTER President and BAUR Vice-President General Manager Editorial and Advertising Offices Johnson, Market Research Mgr. Hoyes, Production Manager. Baur, Typography and Layout, Regional Business Managers New York New York 100 East 42nd St. 100 East 42nd Cleveland Pittsburgh 1016 428 Park Philadelphia Chicago Chilton Bidg. 1134 Otis PEIRCE LEWIS WARREN 7310 Woodward Ave. Box RAYMOND KAY Los Angeles 2420 Cheremoya Ave. ° ° Owned and Published CHILTON COMPANY Executive Offices Chestnut and Sts., Philadelphia. 39, Pa., U.S.A. OFFICERS AND DIRECTORS MUSSELMAN, President JOS. HILDRETH Vice-President GEORGE GRIFFITHS Vice-President EVERIT TERHUNE Vice-President VAN DEVENTER Vice-President BAUR Vice-President WILLIAM BARBER, Treasurer JOHN BLAIR MOFFETT, Secretary JULIAN CHASE THOMAS KANE HARRY DUFFY CHARLES HEALE Member, Audit Bureau Circulations Member, Associated Business Papers the Industrial Arts index. North America, South America and $8; Foreign, $15 year. ° ° ° 1943, Chilton Company Vol. 151, No. This IRON AGE Editorial Four Freedoms Versus 130 Million Freedoms. Technical Articles Per Cent Speed Increase New Drilling Technique Hot Trimming Shell Forgings Automatic Heat Treating Jobbing Forge Shop Douglas Tube and Bender Speeds Plastics and Soap Combined Water-Base Points Design Aluminum Forgings Inspection History Stamped Part Tear Drop Tanks Replaceable Section Arbor Spinning High Explosive Bomb Casings New Equipment Machine Tools ° ° Features News Assembly Line Washington West Coast Fatigue Cracks Dear Editor News and Markets Still More Steel Needed, Washington Says Industry Recognizes Production Numerous Factors Retarding Expansion Farm Equipment Program Given More Boats Needed For Ore Service Plates Dictate Availability Raw Materials Consumption Shows Rise Record CMP How By-Product Producer Operates News Briefly Told Personals and Obituaries Non-Ferrous Metals Prices; Scrap Prices Iron and Steel Scrap News and Finished Iron and Steel Steel and Warehouse Stainless Steel, Tool Steel Prices Semi-Finished Iron and Steel Prices Pig Iron Prices Ore and Coke Prices Ferroalloy Prices Index Advertisers Additional Notes the Cold Treatment Steel, Plastics and Zinc Used Combination Die June 17, 1943 243 | giving use. 101 105 122 169 171 171 175 176 Structural Steels Stock Ryerson Your nearby Ryerson plant has good stock all standard sizes beams, channels, angles, tees and zees available any desired length with adequate facilities for cutting, punching and otherwise preparing the steel your exact specifications. Ryerson also carries large stocks bars, plates, sheets, tubes, stainless, alloys and hundred and one other steel products. Ten plants are strate- gically located for nation-wide Steel-Service. Our engineers and metallur- gists will gladly help you any probem selection, supply, application fabrication. Whatever your steel needs call RYERSON first! Joseph Ryerson Son, Inc. Plants at: Chicago, Milwaukee, St. Louis, Detroit, Cincinnati, Cleveland, Buffalo, Boston, Philadelphia, Jersey City. 44—THE IRON AGE, June 17, 1943 —— = | | 3 ESTABLISHED 1855 ° ° VAN DEVENTER President and Editor BAUR and General Manager DIX Reader Service Markets Editor...D. JAMES Editor.........F. OLIVER WINTERS ° ° ° Associate Editors MacDONALD BARMASEL BENEDETTO Assistants SCHIEN WILLIAMS BUTTERS Regional News and Technical CAMPBELL Pittsburgh 428 Park PHAIR Chicago 1134 Otis MOFFETT Washington National Press BROWNE Washington National Press LLOYD Cleveland 1016 Guardian Bidg. BRAMS Detroit Woodward Ave. OSGOOD MURDOCK Francisco 1355 Market St. Editorial Correspondents ROBERT Cincinnati PENLEY Buffalo FRAZAR Boston HUGH SHARP Milwaukee SANDERSON Toronto, Ont. RAYMOND KAY Los Angeles JOHN McCUNE Birmingham ROY EDMONDS St. Louis JAMES DOUGLAS Seattle Four Freedoms Versus 130 Million Freedoms INCE many people and many organizations are exhibiting blueprints for our post-war world, wonder not now appro- priate hear from the little man who wears barrel. You remember the character the Johnstone cartoons, who might said successor Diogenes who first made the barrel famous. Diogenes was perhaps somewhat better off than his modern successor for merely lived barrel the intervals between his search for honest man, whereas our little friend has wear one. wonder what this little man, this forgotten man, thinks about when contemplating the platform the four freedoms. Freedom from want, freedom from fear, freedom speech, and religious freedom. Probably would say that agreed with them principle but that would like see them brought down earth that he, the forgotten man, might feel their beneficial impact. Perhaps might cite his own personal experience trying get job work that would pay honest day’s pay for honest day’s work. The job that tried get but didn’t was that construction helper government cantonment project. Strangely enough, when applied for his job found that while Uncle Sam was ostensibly the employer and paymaster, the right hire had been farmed out private organization that exacted initiation fee, speak, amount- ing approximately $60 for the right work. Not having the sixty dollars, although badly wanting the job, our little man could not take advantage the “freedom from want” clause the four freedoms. wrote his nephew about this, lad who was member the United Mine Workers’ Union. lucky you are,” said, “to be- long the union and thus have the right work.” But the nephew wrote back that was not working much would like because Mr. John Lewis did not want him work. would like very much work and thus part helping win the war,” said the nephew, “but afraid that did would get head broken.” the little man the barrel discovered that the second freedom, freedom from fear, was more less myth also. said the modern Diogenes, “there still freedom speech left and will exercise when policeman came along and ob- jected his appearing public such bizarre raiment, told the officer and peddle his papers elsewhere. And thus ended, denly, the third illusion freedom. Not being particularly religious, our little man had had enough and did not attempt test out his right the fourth freedom. Three times and out were enough. The this, think, that are going plan free- dom, should divide not into four but into 130 million equal parts. | Preview Bombs for Berlin One shipment Inland plates—20 carloads— outbound for manufacturer aerial bombs + 4 4 4 and Thousands tons Inland plates for aerial bombs only one example the many ways Inland’s entire that output steel being used help conquer Amer- ica’s foes. Steel from Inland moves the West Coast for Lib- erty Ships—to truck, gun mount, and jeep manufac- turers—to Alaska for highway bridges—to makers been containers and numerous other military and naval products necessary wherever America and her Allies new are fighting. desc turn out such quantities steel, the Inland mills The have broken many records, and every Inland mill crew actu aiming for new higher records that will help speed star the day ‘of Victory. flig 4 4 } F } News JUNE 17, 1943 Allied Mediterranian successes have encouraged the stepping plans for the Continental assault. support this acceleration will require least 1,000,000 tons steel above visible supply the third quarter alone, even more fourth quarter. Belief that the war already won resulting too much fancy post-war planning and relaxation pressure the part management, infecting labor with similar lessening urgency. This attitude will have change Washington officials believe that serious impairment the war effort 1944 will result. Aircraft and shipyard labor trouble the West Coast expected employers and union leaders within days unless cost living stabilization more positive and WLB authority unqualified. Three new Canadian molybdenum deposits look very good paper. least one has been offered Jesse Jones for financing. Current Reynolds Tobacco Co. advertisements label the rocket plane "sensational new weapon for victory the air." The only known flying model one Italian machine described German aviation periodicals, which also describe Italian "muscle The muscle force transmitted movable wings and airscrew. The propellor actuated spring, wound before the flight, which operates 1500 r.p.m. After starting, the switch-over "bicycle" muscle power takes place. The plane's test flight was height ft. above the ground. new British ruling reduces cleaning castings minimum and prohibits provement surface appearance welding filling. Naturally they are called castings." Coking coal mines are undergoing considerable mechanization, potential advantages which cannot realized without supplementary coal washing. The Appalachian region putting 20,000 tons (per 7-hr. shift) coal washing facilities, with 22,000 additional tons prospect; Alabama region 4500 tons; the West, 7500 tons, with 8000 additional tons projected. Plastic canteens are being used many soldiers this country. embarkation ports, however, these canteens are replaced the conventional metal type. strictly post-war consumer item plastic screen cloth, although plastic coated wire cloth may even more popular rats find the straight plastic rather tasty. Alloy borings and turnings, now flooding back steel mills, show the following analysis distribution, descending order importance (tonnage): plain carbon steel, X1314, 4100, 4000, 4300, 8600, 8700, Nitralloy, 4600. Segregation the source still more talk than actuality, the result being considerable loss alloy utilization and many Ordnance officials have been shown sensational new drilling technique improvement which increases cutting speeds per cent, gives better hole finish and tolerance and can used unskilled help. The Army glider program swooping up, with award two large contracts last week, one for $31 million Ford for cargo gliders, the other, half large, Gibson Refrigerator for troop carriers. Stainless steel analyses modifications have been numerous since the war started. However, the only type likely extend far beyond the war the chromium-4 manganese grade, which about equivalent 18-8 for applications train and aircraft construction, and slightly less expensive. vintage April, 1941: "Suppose had air force that could send Europe. Where could operate? Some our squadrons might based the British Isles; but physically impossible base enough aircraft the British Isles alone equal strength the aircraft that can based the continent Europe." That was Lindbergh speaking. Recent Berlin photographs Hitler with commanders the Russian front show that Hitler still seems command the Wehrmacht. Particularly interesting, ever, the fact that all officers shown belonged, before the war, the Russians" among the German generals, whose spokesman was the present Generaloberst Ruoff, chief staff the von Manstein Army Group. Field Marshal von Richthofen, who had succeeded Generaloberst Lohr the Fourth Air Fleet, has always been impressed the Russian armed forces. | | | | } | | * | Per Cent Speed Increase New new drill press attachment which permits notable increases drilling speed and provides improved hole finish and tolerance and longer tool life described herein. This device provides auto- matic axial reciprocation the drill and produces small, uniform chips and unusually effective metals. NCREASES drilling speeds per cent over handbook ratings, improved hole finish and tolerance and greater safety the press operator are among the im- provements drilling operations re- ported users new drilling at- tachment developed Bastian-Bless- ing Co., Chicago. The attachment, called the Rego Karweit Driller, only slightly larger than chuck and may fitted any type drill press and applicable ABOVE the new Rego Kar- weit driller (arrow). The outer hous- ing the unit does not revolve. 48—THE IRON AGE, June 1943 both automatic and sensitive feeds. The driller indicated the arrow Fig. Possibly the best method illus- trating some the characteristics drilling operations when using this device compared with conventional drilling methods would relate the experience demonstration held recently for ordnance officials. mounted vise the drill. was The BELOW 2—Small uniform chips resulting from the use this new drilling de- vice are shown this illustration. Ma- terial being drilled SAE 1020 steel. fecd was set 0.004 and the speed 1800 r.p.m. The drill size was in. the drill bit into the steel, the observers backed away, keep clear the long, hot whipping chips and splashing lubricant commonly asso- ciated with drilling such steel. But, the drill flutes slowly dis- appeared into the steel, there were long whipping chips and splash- ing, instead steady stream small chips bubbled out the drill flutes and were gently carried away the coolant. The first hole went down di- ameters before the drill drawn. One observer, ordnance official, approached the drill de- termine how hot was. After some cautious experimenting, found could comfortably grasp the his hand without being burnt. was just slightly warm. Another hole was drilled, this time diameters the same feed and speed, and with the same small chips, the same cool drill, and the same lack large chips and splashing, smok- ing lubricant. Then followed other equally startling demonstrations aluminum, magnesium and sticky cop- per and other materials. This demonstration, which has been repeated many times under practical operating conditions, highlights some the unusual characteristics this driller. Taking one time the questions which naturally arise from such demonstration, the unusual perform- ance the drill primarily the re- sult reciprocating action which the Rego Karweit driller superim- poses the drill feed. This action not noticeable the eye when the press operating but may felt the hand placed the driller. The housing the driller, shown Fig. and does not revolve with the spindle. stationary. The rod the right the driller the photo- graphs serves keep the driller cas- ing from revolving. This method locking the casing was used for the demonstrations, but other means achieving this end are being used drill ° ° ° the Russian armea Drilling Tec production setups and built into units. This reciprocating movement the drill the result the interruption the drilling feed once each revolu- tion the mechanism the driller. During this interruption, which en- tirely automatic, the cutting edge the drill lifted slightly from con- nique PHAIR Western Editor, THe tact with the bottom the hole, the amount this retraction being only very small fraction inch. This motion cuts the chips free from the 3—A comparison drilling operations with and without the Rego Karweit driller. Photos the left show operation without this attachment. Note the chip formation and splattered drill press. Photos right show same operation but with the drilling attach- ment. Note how quietly the lubricant lies and the absence stringy, twirling chips. THE IRON AGE, June 17, f ; | h | ° 1°) ~ e i work and permits the lubricant flow under the cutting edges cool and lubricate them repeatedly throughout the drilling cycle. The chips produced this driller are substantially uniform size and shape for given drill size, regard- less the material being drilled. The size the chips are regulated small enough clear the drill flutes easily, yet large enough and curled sufficiently that they will not pack the flutes. The type chip resulting from drilling 1020 steel The recurring lifting the drill, accomplished entirely mechanism built into the driller, sets vibra- tory condition whereby the chips are kept constant agitation. This main- tains looseness beneficial the clearing through the flutes being washed out the flow the lubricant. With the chips moving freely and loosely the flutes, there bind- ing and scoring the side walls. And thus eliminating the “feel the feed” unskilled labor may operate the press with little danger drill break- age. matter record that use the drilling attachment has made possible employ automatic feeds where previously only sensitive feeds were feasible. Fig. illustrates the most notable visible difference drilling with and without the Rego Karweit driller— the chip formation. The two photos the right show the attachment operation (arrow) while the two photos the left are without the driller. The material, the placard indicates, SAE 1020 steel, the drill size being 5/16 HS, the feed 0.0036 and the speed 1330 r.p.m. The photos were taken various stages each cut and show the comparison between long chips resulting from the usual drilling procedure and the small chips resulted from the use the Karweit driller. The fact that the coolant given opportunity bathe the cutting edges once each revolution probably accounts large measure for the cooler tool performance quently longer tool life reported users the attachment. many installations date has been found that the wall finish im- proved the point that the hole can drilled size without reaming. This condition has been reported several jobs, including parts mate- rials such SAE 4140. The Rego Karweit Driller can used with any conventional drill press, along with standard drills sharpened the conventional manner. will 4—Comparison drilling time between conventional automatic feed setup and automatic feed with the Rego Karweit attachment. The material was chrome- moly steel 224 Brinell. Speed and feed were identical both cases. 120 Drilling time seconds IRON AGE, June 17, 1943 Depth drilled, inches noted that the photographs high spiral drill was used. has been found that this type drill works little better than the regular style, although the regular type accep- table. The driller equipped with tapered shank and tang and merely inserted the spindle would drill chuck. Use this new de- vice requires changes coolant practice. desirable that the drill press should sturdy and sufficiently rigid that any spring between the head and table under operating conditions does not exceed the feed distance the drill per revolution when the drill head and bed are subjected the feed pressure expected used with the drill. Generally speaking, the drilling time particular hole, especially deep hole, reduced under other- wise identical conditions since the con- ventional repeated withdrawal the drill, including step clear the flutes eliminated. With the Rego Karweit driller possible drill holes one pass the extent permitted the length the flutes. The only action the operator continuously feed the drill. example the performance the Rego Karweit driller, reported which the performance the drill- compared with the time standard step driller drilling forging material having Brinell 224. The feed rate both cases was 0.004 and the speed 917 r.p.m. The step driller, the chart indicates, took 116 sec. while the Rego Karweit driller required sec., reduction sec. about per cent. The second graph, Fig. shows the relationship time saved us- ing the Karweit driller, with proper feed, deep hole drilling alumi- num where manual feed would used under normal practice. The short vertical lines the “manual feed” line are representative the time lost pulling the drill out clear the flutes. the question drill life, hole size and alinement, the following data, based three months’ run, with production setup, illuminating. The tolerances this job were —0.000 0.003, SAE 1020 steel, using in. The reject rate originally was per cent. When the Rego Karweit driller was placed operation, un- der otherwise identical conditions, the percentage rejects was cut 0.5 per cent, production was increased from 200 300 pieces per 8-hr. shift and dri peared. new dri ing hardnes drills, app with wherea: weit before Power and spe drilling 4140, Rego turret duction spotting reaming spiral drills Hand and fee ence ratings per cen The removes ping off, the operatic ing plant form, The line sizing simple trench high prod the Since the cutting held and drill breakage practically disap- peared. Citing other experience with this new driller, user found that drill- ing steel crankshaft with Brinell hardness 341 and using No. drills, the drills had resharpen- approximately every seven holes with conventional drilling procedure, whereas when using the Rego Kar- weit driller, holes could drilled before resharpening was necessary. Power feed was used both cases and speed and feed rates were identi- cal. another instance, involving the 9/16 in. hole SAE 4140, three-spindle press having two Rego drillers was substituted for six turret lathes and gave the same pro- duction with improved results. The spotting, pointed drill drilling and performed the lathes was Standard heavy web high spiral drills the drill press were successfully substituted for oil flute drills previously used the lathes. Hand book tables for cutting speeds and feeds still apply, although experi- ence has shown that cutting speed ratings can safely increased per cent above the hand book ratings. The elimination the long chips removes obvious safety hazard and Drilling seconds Diameters drilled with drill Depth drilled, inches Fig. 5—A comparison drilling times aluminum. adds the adaptability unskilled help drilling jobs. Too, the gener- ation small chips, simplifies collec- tion and segregation the borings. Hot Trimming Shell Forgings shell forging while still hot the forge plant, the shell trimmer shown saves the cost ship- ping the extra weight the end cut off, the cold-sawing cutting off operation usually done the machin- ing contractor and considerable scrap handling. obvious that the forge has one more operation per- form, but the saving the machinist great that this arrangement warranted. trimming the crop end the The machine set the forge line immediately following the final sizing operation. means simple adjustment, shell forgings size from the 60-mm. trench mortars through the 155-mm. high explosive shells can cropped. production 270 cuts per hr. the 105-mm. shell can Since the bottom the shell forging cavity held firmly against the end the gaging mandrel during the operation, the length can held close tolerances that treating line. the left foreground the charging table where trays are loaded and then pushed through the hardening furnace. Shown behind the hardening furnace the quench tank, with conveyor the draw furnace. subsequent facing operation neces- sary the machining line. The machine nearly automatic operation, the hot forging being slid from conveyor over the mandrel. When the start button depressed, air operated arm swings into posi- tion and holds the shell against the mandrel which locates from the bottom the cavity. While held this position, the forging rotated the two driven trunnion rolls that support it. The disk type cutter now fed automatically through the forging wall. roll located the mandrel prevents the formation internal burr. completion the cut, the op- erator ejects the forging along with the cropped end actuating air operated ejector, and the cycle re- peated. Cutter life unusually good that continuity operation can maintained. This shell trimmer was developed the Yoder Co., Cleveland, col- laboration with the Bradford Mfg. Co., Bradford, Pa., which makes shell forgings. THE IRON AGE, June is 7 | id @ | | we! 3 ni- ‘he the Automatic Heat provision continuous automatic heat treating. for use the average jobbing forge shop, difficult, due the wide variety products which must handled, and the varying nature the heat-treating cycles involved. The General Drop Forge Co., falo, finding that its volume heat- treating work was increasing rate impossible handle existing batch type equipment, made study available furnace equipment and set the following requirements: The equipment must preferably the continuous type for compact- ness, uniformity treatment, and economy fuel consumption; must operate with minimum labor, all handling from the hardering fur- nace the receiving tote boxes, must automatic; the temperatures hardening and drawing must sub- quenching tempersture must under adjustable and auto- matic control, and both the time the hardening furnace, and the time the draw furnace, must inde- pendently variable; the equipment must designed that the harden- ing furnace can operated inde- pendently annealing normal- izing furnace, while the draw furnace operated independently and simul- taneously stress relieving draw furnace; and the equipment must designed handle wide variety products, ranging from small knuckle shock absorber arms, weighing only one large parts general view the equipment which was installed meet these consists essentially pusher type hardening furnace, conveyor type quench unit, with. oil cooler and oil system, and conveyor type draw furnace. IRON AGE, June 1943 Manager, Special Furnace Division, Dempsey Industrial Furnace Corp. ° ° ° Pusher type equipment lected for the hardening furnace be- cause the heavy loads involved, and the high maximum temperatures required (1800 deg. F.). The trays are loaded the furnace operator the small charging table shown the front end the furnace, and pushed into and through the furnace chain type pusher with receding head. The trays are supported within the furnace chamber alloy roller rails which extend the entire length the heating chamber. the discharge end the heating chamber, the trays pass onto tip- equipped with fingers for holding the tray position during the dumping operation, and operated matic cylinder, controlled electrically operated solenoid valve, which turn operated limit switch when the tray positioned the tipping platform. the tray reaches this position, depresses limit switch arm, causing the small door the side the fur- nace opposite the discharge position open pneumatic cylinder. When this door the position, the tipper platform elevates, thereby sliding the work off the tray and down the chute into the quench tank. The door then closes, and the tipper platform, with the tray still place, lowers its original position. When the next push takes place, the empty tray which has been retained the tipper platform, pushed ahead onto sloping discharge conveyor, which delivers outside the rear door the furnace. From this point the fur- nace operator picks the tray Treating means overhead monorail and returns the charging end the furnace reloaded. The furnace the type with low pressure staggered along both sides the furnace, firing into chambers below the alloy rails prising the furnace combustion chambers are covered spanner tile spaced prevent flame from entering the chamber, while still permitting sage the hot products tion. The furnace heating cycle trolled time clock, which may adjusted heating times ranging sired use the furnace for annealing normalizing, the tipping mechanism may cut out cycle, and the work and trays charged automatically onto the charge table, instead through chute into the quench tank. For temperature control, the nace divided into two controlled zones plus discharge bule section which includes the tip ping mechanism. The first zone primarily bring the work and trays from room temperature possible. The second zone tration the heat throughout sections, and permit time for metallurgical changes take within the material. The third tion, insure that the material not cool the tipping table being quenched, provided with fairly high ratio heat liberation compensate for the losses about two discharge doors. The quench tank equipped wooden bumper bars, which take bump when forging com down the chute, and allow the of a wat oil wat oil ente forg und the rfired com- These any Jobbing Forge Shop settle onto the conveyor with less blow. The quenching medium usually used cooled heat exchanger. The quenching temperature controlled automatically thermostat the oil line, which actuates valve the water line the heat exchanger. The oil pumped through manifolds with openings the point where the work enters the oil. Work this sort, direct from the forging hammers, may expected shed considerable scale quench tank. take care this accumulation, access doors have been provided near the bottom the tank, under the conveyor. water When desired use water quenching medium, instead oil, the pump may used withdraw the oil from the tank. The motion the quench tank conveyor mittent, and controlled sepa- rate time clock. the work leaves the quench tank, deposited automatically the draw furnace conveyor, without manual rehandling. This eliminates the use another furnace operator charge the draw furnace, and enables one man handle the com- plete harden-quench-and-draw unit. The draw furnace conveyor con- sists heavy wire mesh belt, rein- forced with heavy cross rods, and with malleable iron chains taking the actual load. The conveyor travels alloy skid rails supported above the actual furnace bottom refractory piers permit under-fir- ing. The draw furnace fired low pressure gas burners firing into com- busion chambers below the conveyor, from which they are separated spaced refractory tile forming the top the chambers. The draw furnace divided into two separately con- trolled zones and provided with re- cording pyrometers. The draw fur- nace conveyor driven ratchet mittent cycle under the control time clock. The unit operates under the widely varying conditions often encountered jobbing forge shop. For this reason actual fuel consumption values vary widely. For the average work, however, the fuel consumption ranges from 1.0 1.4 cu. ft. 1000 BTU natural gas its equivalent, per lb. material treated the entire heat- quench-and-draw cycle. ™ hiss THE IRON AGE, June 1943—53 | is de- dis Douglas Tube Bender Speeds REATLY reducing time la- borious hand bending older methods, Douglas Aircraft Co. has designed and installed manually operated speed benders which increase the output per operator ten times more per shift. With the bending method still vogue throughout the aircraft industry, workman single shift period can produce maximum approximately ABOVE IG. reference job analysis sheet furnished with the order, the opera- tor selects correct radius block (operator's right hand) and mandrel (operator's left hand) for the specified tube size. Lubri- cated hardwood slide block shown clamped machine. Semi-spherical nosed mandrel insert slid inside tube passes between radius block eliminating possibility tube collapse distortion. 54—THE IRON AGE, June 1943 250 units the average job. long run requiring few set-up changes the speed bender will turn out many 3700 parts per hr. shift. Set-up time averages min., the machine numerically listed job analysis sheet furnished the operator with the material. Tube sizes from in. outside diameter 0.049 in. wall thickness can handled with the present equipment. Designs for ier tubing, though practical from operation standpoint, have not proved necessary for Douglas requirements. one Douglas plant six these machines are used. The cams can set produce many nine sep- arate bends one tube. The accom- panying pictures show typical set-up and its progression from steps completion the part. BELOW 1G. 2—Referring directly the job analysis sheet, the operator sets the stops for beginning each bend they occur along the longitudinal length the tube. Note calibrated disk right center, easily visible from the work position, and used next operation. | ci radi tubs Fe > Output ° ° ° RIGHT set upon the calibrated disk and coordi- nated with the cam stops described the next picture. RIGHT 5—Tubing section previously cut correct length slid onto mandrel and radius block adjusted snug fit hold tube firmly against slide block. Block adjusted handwheel and screw and has cam lock for quick release. LEFT 4—Cam stops are set allow de- gree bend radius distinguished from angle rotation. This provides actual stop for each bend without further attention the part the machine operator. THE IRON AGE, June 17, iy ABOVE now proceeds with the first bend. The clamp extension from radius block equipped with hand grip, and acts lever facilitate bends. Note cam lock radius block adjusting screw. 56—THE IRON AGE, June 17, 1943 BELOW 7—Third bend different plane, requiring rotation the tube, the calibrated disk. The progression bends operator cannot make incorrect bend, providing original set-up correctly made. LEFT IS. rotation tube, third bend accomplished, completing total bends the part. ines parts pers soap men ing wa » p ac BELOW 10—Supervisor Goforth exam- ines uniformity absolutely identical parts produced with the speed bender fraction the time used former bend- ing methods. Plastics LASTICS and soap today are com- bining number products give superior results over the former products they are now dis- placing. large variety resins, and natural, are being dis- persed water means ordinary used paints, rubber ce- ment extenders, textile waterproof- ing and finishing agents, car polishes and still other diversified fields. These new products, are saving large quan- tities organic solvents vital other uses. One the most revolutionary the plastics-soap combinations the recently perfected water-base paint. use the army, navy, and large war plants, this type paint free from poisonous, expensive and inflam- ABOVE 9—Trigger spring release opera- hand frees tube from the chuck mechanism, allowing withdrawn from machine through the radius and slide blocks. Machine operator examines first part, which carefully checked against the template the initial run. After part proved, further check has been found necessary for repeat runs. and Soap Combined Water-Base Paints mable organic solvents, mixed with readily available substance—water, hus high covering power, and great resistance wear. Moreover, these paints dry few hours and may applied damp surfaces. Pigments, plasticizers and other materials are generally mixed with the synthetic resin. (British patents 349,988; 539,288 and 334,567.) THE IRON AGE, June ig | ik % — Design Aluminum general forging and die design principles relating hammer forgings. Upset forgings and press forgings will dis- cussed later articles. For overall discussion aluminum alloy forgings, the reader referred earlier article, Alu- minum The Age, Sept. 10, 1942. combine many advantages: con- trolled grain absence porosity, high allowable stress, ample filleting and great structural sound- ness. wide variety forged shapes can produced aluminum, allow- ing the use fewer parts and fre- quently permitting them serve more complex functions. Complexity the design forg- ing, the other hand, greatly in- creases die cost and often poses seri- ous forging problems. The attainment maximum simplicity design for prescribed functional requirements offers, therefore, challenge the forging designer. Hammer forgings generally start bar billet stock and are worked into their final shape hammering oper- ations various dies. The complete that for steel forgings and includes fullering, edging rolling, bending, blocking and finishing. Frequently the manufacture particular forging does not require all these operations and the steps are, course, omitted. EDGER FINISH IMPRESS! Fullering done extremely sim- ple dies. Its purpose reduce the cross-section and extend the length the stock the approximate propor- tions required. The accuracy fuller- ing depends most cases upon the skill the hammer operator. Edging gives the stock rectangular cross. section and distributes the mass metal more definite positions with respect the forging’s ultimate shape. Rolling does fundamentally the same thing, but employed give the metal round cross-section. When necessary alter the axis the stock before blocking and finishing, bending dies are usually used. Frequently more than one set bending dies needed where the bending procedure complex. Blocking dies contain approxi- mation the final forged shape and are used work the metal into rough- final condition. These dies also serve eliminate any excess material forcing out into the gutter around the die cavity. some in- stances necessary trim off this material (called flash) before the fin- ishing operation. UTTER FLASH RIM LEFT. Typical small aluminum forging die. TYPICAL SMALL FORGING DIE 58—THE AGE, June 1943 PARTING PLANE The only dies whose faces are brought together the hammer-forg- ing process are the finishing dies, which work the stock into its final shape and size. When the forging produced extremely simple and the quantity made small, the whole process can often accom- plished finishing dies. such in- stances the blows the reciprocating die block must carefully controlled work the metal gradually. One set die blocks containing all the necessary die impressions may used the production small forg- ings, Fig. Larger forgings, how- ever, may require the use several sets dies order prevent the equipment from being unwieldy. The greater the number dies required for particular job, the greater the relative original cost producing in- dividual forgings, and this cost can absorbed only manufacturing large quantities the product. General Design Considerations The forging (or parting) plane chosen the designer, and lies right angles the direction which the reciprocating die travels. the plane from which all draft angles are calculated, and must chosen with considerable care order pro- duce forged parts having greatest functional value and requiring little subsequent machining. The line along which the lower and ORGING DIRECTION Lock PARTING LINE ABOVE 2—Forging parting plane and parting line dis- tinguished. The die lock shown should that Fig. upper partir with regul: webs one never lar) profil: rule sir ing the the clude culat loads comp lock posit face, used fib: direc high direc ized forg econ part than mad elon; and the SHANK upper dies separate known the parting line, and not confused with the parting plane. (See Fig. 2.) may straight and lie along the ferging plane; may made ir- regular accommodate bends, lugs, webs and the like the forged part. often possible design forging that all the impression within one die. Single dies this sort may, nevertheless, require broken (irregu- lar) parting lines. run the parting line through the profile the forging’s web—if there web—and the profile need not the center line. course, this rule cannot followed the case single dies, for obvious reasons. When the parting line the forg- ing dies irregular from any view, the resultant meshing the dies die lock, Fig. (see also Fig. 2). When choosing the forging plane, the designer should careful in- clude the effects die lock his cal- culations that unbalanced sidewise loads the hammer can avoided. sidewise load this sort can compensated placing opposing lock (counter-lock) the die position away from the forging sur- face, but such remedy should used only cases strict necessity. The working aluminum elongates the grains the metal and produces fibrous internal structure which has directional mechanical properties. The higher strengths which result the direction grain flow should util- ized best advantage designing forgings. will frequently found more economical and practicable bend part after has been forged, rather than forge the bend into the part. Bending may done while the metal still hot, even after has cooled. Allowances for such bends should made when designing, since bending elongates the fibers the tension side and builds them metal) the compression side the metal. The radii bends should Hammer INKING die that will used forging aluminum aircraft part. not less than twice the thickness the part point bending. obtain more efficient product, produce part which otherwise could not forged according speci- fications, sometimes necessary twist after forging, and round sec- tion adequate length for clamping and twisting should allowed. The tolerance for twisting should deg. Details Design Draft angle the taper given the side walls the die impression, and necessary prevent the forg- ing from sticking the die (see Fig. 4). Drop forgings normally require draft angle deg. for depressions the die and for average-size plugs projections. Plugs which form very deep cone frustrums will require draft angle deg., however. Draft angle function die motion, and always caclulated from the forg- ing plane, not from the parting line. With modern high impact velocity drop hammers, possible get with draft angles low deg. such hammers, the return velocity, the dies are parted, almost great the impacting velocity. This rapid parting the dies permits the explosive force the volatilized lubri- cant effectively blow the forging from the die. This rebound gov- erned the ratio the weight falling parts and the mass metal the anvil. These big hammers not only have heavier ram weights but proportionately much heavier anvils. Some the biggest steam hammers the country are being used aluminum forgings. When the regular draft not match the parting line, the draft one die increased until the contours both meet the parting small ledge can added the shal- low die, but this method not sat- isfactory and should used only when the previous method not feasible. Corner radii sufficient amplitude must provided forging flanges cracked dies are avoided. The chart, Fig. shows recommended val- ues. Flanges should also thick possible reduce die breakage and die cost. often important, how- ever, that flange thickness reduced minimum because weight and other factors, and the designer must exercise his ingenuity the forged part perform its proper func- THE IRON AGE, June 17, red the can hich gles ittle and | The dies used forging aluminum alloy spray gun*handle. tions and still practicable from manufacturing standpoint. relatively wide flanges, where flat with minimum radii the cor- ners would the added diffi- culty forcing the metal into such corner radii makes desirable de- sign these flanges with full radius the top, Fig. bath-tub-type forgings the inside edge radius should equal the wall thickness when- ever possible. The outer edge, course, should not given radius. Corner and edge radii should remain constant along ribs and flanges or- der that die sinking may done with one tool, even though the section tapers height. Small fillets restrict the flow metal into the deeper crevices the die, and may result lap, folding over the metal itself. laps are avoided, fillets should made large the design allows. Small fil- let radii also cause excessive die wear the fillet, cause die breakage be- cause the high pressure needed force the metal over the fillet. The designer must therefore remember that the use small radii very deep and narrow plugs, very wide ones, will result increased cost dies and forgings. The chart, Fig. showing minimum fillet radii val- ues, based for simplicity plug 60—THE IRON AGE, June 17, 1943 depth alone. These values hold for plugs width-to-depth ratio approx- imating 2:1, and for all T-sections. Fillet radii that vary will cause increase die price because they must tapered hand. usual- feasible retain constant radius over most the length moder- 3—Die lock forces should counterbalance each other the left. (P.L. the parting line.) 4—Matching draft angles unequal flanges. RECOMMENDED ately changing section without penal- izing the design excessive de- gree, and this should done when- ever possible. The need for large outer radii the bath-tub type forging should emphasized, since die breakage this point presents considerable problem. minimum, such outer radius should equal the fillet radius plus the thickness the thinner web. even larger radius than this minimum often possible and always highly desirable. Problem Thin Webs Thin webs present relatively great area metal contact with the cooler dies, and therefore dissipate their heat rapidly. Being cooler than the rest the forging, they become harder forge and the whole part must hammered more severely. The result rapid breakage dies. Deeper cavities the dies may fill offer strong resistance filling before the web brought down size. The flow excess metal into the gutter will then shear the various sections into separate parts. the thin web must retained, the fillet radii must increased considerably. The same difficulty restricts the use webs ex- tending beyond the flanges shaped sections. Two methods are commonly used produce better forgings and better structural parts when the above con- ditions prevail. The first thicken the web gradually from the center outward and increase the fillet radii; the other punch out FORGING PLANE ANGLE GREATER ALTERNATE METHOD PREFERRED METHOD large latte gutte later porte out requ may out. fin larg spec trim tions requ tion: shou The tort espe the the and any flan pun the whi min for; | | : | EDGE AND CORNER RADI! FOR THESE USE THIS CHAR large portion the web, Fig. The latter expedient permits using gutter that portion the web which later will punched out. unsup- ported thin edge around the punched- out section may not meet strength requirements and improved section may obtained beading the cut- out. small parts with fin-like lateral projections from globular center, the fin may drop-forged minimum thickness 1/16 in. with width more than in. Flash may trimmed off with much 1/16-in. undercut, may left protrude 1/16 3/16 in. larger forgings. The prices com- mercial forgings not include any special grinding finishing the trimming line, all trimming opera- tions are difficult control and those requiring high accuracy entail addi- tional cost. cases where any part the trim line must held closely size, detailed notes this effect should placed the designer’s drawing. Holes Punched Hot Holes lugs require the forging local depression until web in. thickness remains. The web punched out while the metal hot. The punching operation tends dis- tort adjacent sections the forgings, especially the web thicker than the surrounding flanges. avoid distortion, considerable area should left between the flange and the punched hole. Holes should start the point tangency the fillet and the web; they should not include any the fillet and draft the flange. punched web, the final trimming the flash and web can accom- plished more easily small amount the web left around the inside the part provide bearing with which hold the forging during trim- ming operations. The tolerance the length forging may well excess that Recom- mended edge and corner radii for aluminum forgings. allowed the machined parts. For links and similar parts, where bosses machined are set some dis- tance from one another, good practice make one boss circular and the other boss (or bosses) elongated plus minus the forging length tolerance, even portion the end HARD full radius preferred relatively wide flanges. boss must later machined off avoid interference (see Fig. 9). Tolerances Thickness tolerance applies the overall thickness the forging, and varies with the net weight the prod- uct being fabricated. figured sep- arately and independently any other tolerance, and applied direction perpendicular the parting plane, parallel the ram travel. Tolerances closer than those listed Table will FILLET RADI! mended fillet radii for aluminum alloy forgings. FOR ALL FILLET THIS necessitate the use either coin press die complete cold restriking die. Mismatch caused slight mis- alinement the forging dies, and re- forging along the parting line from its relative position the other part the forging. Shrinkage, which re- sults from the cooling the metal, causes dimensional contraction all directions. The designer should add enough metal compensate for shrinkage and mismatch (Tables and III). The allowance should never the sum the two. Whichever fac- tor requires the greatest tolerance given direction governs the allow- ance. stock for machining neces- sary, must addition shrink- age and mismatch tolerances. The designer should specify the largest practical tolerances for die wear that the design will permit. commercial forging practice the im- pressions are machined the lower limits the drawing dimensions, and when the impression has been worn the upper limits the die must re- particular part are halved, the die life will also cut two. Large di- mensions (such length) should allowed vary +1/32 in. per foot (0.003 in. per in.). Dimensions across the parti