The Iron Age 1945-02-15: Vol 155 Iss 7

| levelop- best es-made Power. ) S.A Advertising Offices LEONARD General HAYES Advertising Manager JOHNSON, Manager Service and Market Research BAUR, Production Manager Business Managers New York New York Cleveland Pittsburgh Bidg. 428 Park icago Bidg. 1134 Otis Bidg. Detroit Hartford Conn. RAYMOND KAY Los Angeles 2420 Ave. Owned and Published CHILTON COMPANY Executive Offices Chestnut and Sts. Philadelphia 39, Pa., U.S.A. OFFICERS AND DIRECTORS MUSSELMAN, HILDRETH GEORGE GRIFFITHS Vice-President EVERIT TERHUNE Vice-President VAN DEVENTER BAUR Vice-President WILLIAM BARBER, Treasurer JOHN BLAIR MOFFETT, Secretary JULIAN CHASE THOMAS KANE HARRY DUFFY CHARLES Member Audit Bureau Circulation Member, Associated Business Papers the Industrial Arts index. Pub- lished every Thursday. Subscription Price Nerth America, South America and Possessions, $8; Foreign, year. Single Copy, cents. ° ° ° CLEARY, Sales Promotion Manager 5) Vol. 155, No. February 15, 1945 Editorial Technical Articles Crushed Wheel Dressing Form Grinding............. Diamonds Impregnated Carbide..................... New Titanium Steel for Vitreous Enameling............ Equipment Can Twice Much.................... Laminations Welded Steei Improved Method Precision Boring................. Features News and Markets France May Produce Own Reconstruction 112 Foundry Industry Melted Million Tons 114 Large Helium Supply Now Available................... 120 Labor Supply Drops From Wartime 124 and Canada Agree Plant Disposal 126 Discusses Powder Metallurgy 130 Coke Makers Form New 132 Diesel Developments Saves Fuel.................... 138 Contract Delays Slow 144 Machine Tool Market 154 Nonferrous Metals News and Prices................ 156-157 Iron and Steel Scrap News and 158-159 Comparison Prices Week and 160 Finished Iron and Steel, Steel 162 Warehouse, Semi-Finished, Tool Steel 163-164 Steep Pipe, Tubing, Wire Products, 165-166 Stainless Steel and Ferroalloy Prices * e | ad | if | ° ° ° from Brass Manufacturer: finished with original H.W. die. Results four times greater than with any other Forge Company: ing record H.W.D. above any other steel." fro average punches running over 50,000 holes and still running Best revious record with other steel dies holes." HWD DIE STEEL Performance pick Firth-Sterling quality random giv output steels assurance that quality and exceptional tou H.W.D. ing formi severe pre genera H.W.D. Buileti oper- SL-2014. The Firth-Sterli six other THE IRON AGE, February 15, 1945 from Automotive Manuf acturer: pieces grinds averaged Cromovan between from steel Manufacturer: per average produ rolls Crom for heading stee DIE STEEL Where production ness (preventing sinki resistance, unusual ved during sinking), and mini ual depth hard end for Cromovan Bulletin SL-2022 The Firth-Sterling lin ing line OFFICES: McKEESPORT ORK HARTFORD PITTS CLEVELAND . DAYT . hard ynal chang dies, die sicels Feb. 15, VAN DEVENTER and BAUR and General ° Editorial Associate WINTERS JACK HIGHT ALBIN JOHN ANTHONY BARMASEL DAVIS News and Technical Pittsburgh 428 Park Bidg. POST Chicago 1134 Otis Bidg. OFFETT BROWNE EUGENE HARDY Washington Bidg. LLOYD 1016 Guardian BRAMS Detroit Woodward Ave. OSGOOD MURDOCK Son Francisco 1355 Market St. ROBERT Cincinnati DEAN Buffalo FRAZAR Boston HUGH SHARP. SANDERSON Toronto, Ont. RAYMOND KAY Los Angeles McCUNE St. JAMES DOUGLAS Seattle Fitting the Peg the Hole have touched upon the current pressures leading the direction state ownership, which alias for state social- ism. Under pure, even under impure, state socialism, the state be- comes the owner manufacturing facilities, farms and other property. Taking possession naturally leads having the deciding voice the appointment those controlling the management industry and business. Under these circumstances and with the impossibility divorcing politics from state ownership, the natural conclusion would that poli- ticians would eventually find ways and means appoint the managers our industrial and other establishments. think that this self-evident from the record established Russia under communism; Germany under nazism and Italy under fascism: Three different names for one thing, namely, state socialism. let’s imagine that have reached, this country, the ultimate goal the leftists, which the Amalgamated Motors Corporation America seeking employ chief elettrical engineer. For your information, background for the ensuing scene, let say that Amalgamated Motors government owned corporation com- bining General Motors, Ford, Chrysler and what have you the auto- motive field. what process equity otherwise, the ownership and control these corporations was shifted from private political hands beside the question. The point that the power making many hundreds appointments responsible positions managers industrial and busi- ness affairs has been taken out the private enterprise arena and tossed into the political bull-ring. the scene now envisioned laid the Senate Chambers, where Joe Doakes being considered nominee for the position chief electrical engineer Amalgamated Motors. Now not let give you the false impression that Joe sought this job. sure that he, aware that knew nothing about electricity, would never the world have made application for it. But being what known “lame duck”, and having because public opinion been kicked out one political office, the powers that had him the card file for first consideration when government took over industry. Joe Doakes goes before Senate Committee which pass upon his qualifications for this electrical engineering After the ordeal over, Joe goes back his best friend, who asks him what happened. “Well,” said Joe, “they asked believed God; whether was right handed, left handed ambidextrous and whether preferred Mr. Stalin Mr. Roosevelt both.” “What did you tell them?” inquired his friend. answered ‘yes’ all the questions,” replied Joe, “and think have the job cinched.” “Did they ask you what was the difference between watt and kilowatt?” asked the friend. and told them: “What’s the difference.” Which all goes show that not what you know, what you are that determines your job under state controlled economy, but whom you know. | | 4 MILLER HANSEN Many test casts are made Inland’s search for new and better steels. Feb Inland Steels for Tomorrow Inland makes steel heats few pounds each for experimental purposes, and pro- duction heats 100 150 tons. The small experimental heats are run two induction type furnaces, located especially equipped department labora- tory. These pilot heats are the forerunners the steels for tomorrow. Making small casts steel one phase Inland’s continuous research for better methods producing steel, and for better steels that will make better products. Inland research that already has pro- high-yield strength Hi- Steel, and lead-bearing, faster machining Ledloy. The newest creation Inland research Ti-Namel—the new vitreous enameling alloy steel which white en- amel cover coat applied direct the base metal. Ti-Namel assures superior quality finish, longer life, and lower shop costs. These new Inland steels, and those that are yet come, will important man- ufacturers competing peace- time markets. Track Accessories Sheets Strip Tin Plate INLAND STEEL COMPANY Dearborn St., Chicago Ill. Sales Offices: Cincinnati Detroit Indianapolis Kansas City Milwaukee New York Paul More War Bonds and them. spe hé The will have operational squadrons fighters action Soon, probably within the fortnight. onds Industrial activity France still low ebb, through absolute overty raw materials and lack such routine items workmen's gloves, etc. commitments for raw materials have not been filled. promise shiploads materials for January resulted only shiploads being delivered. The desperate plight industry there, will partially corrected shipments will made month so. Current production France for the war effort confined some small steel few batteries, heavy cotton duck, and some heavy bridge girders. French industrialists are running out money. law idle workmen are paid per cent their wage the plant, and the Government later makes these payments Since invasion, however, the government has not covered these payments, and just announced that the industries will investigated profits during the determine whether such payments will made. Introduction the isothermal treatment liquid baths for Army Ordnance pistol has resulted not only considerably fewer rejections heat treated parts further has increased total pistol life. The cartridge extractor was the first part subjected the first practical tests, 100 extractors were heated immersion bath 1500 deg. F., followed transfer another liquid bath held temperature 600 deg. addition fitting the form gages after this with required hardness all testing points, these extractors when held close the extraction hook could bent hammer blows inward outward from the cartridge deg. angle without fracture. And: Endurance tests showed extractions 15,000 and 20,000 with deformation the extraction hook and loss spring tension. Other parts now being subjected austempering with similarly improved properties the barrel bushings, safety locks, ejectors, disconnectors, barrel links and stop plates. Boron additions high speed steel have been found lower cutting for given tool life when compared with untreated steels having the same hemical analysis and Brinell hardness. Also: Machinability the steel was impaired the addition boron. Chips rom the steel seemed more continuous and not well broken the untreated steel. Chip coils from bars with boron additions were larger than hose the untreated steel when turned the same speed. Ladle additions titanium aluminun-killed steel the ratio 4.5 titanium carbon will add the enameling quality steel sheets. This addition erts the carbon steel more stable form, thus preventing its reaction with xides the enamel coatings form gas and blisters. Steel sheets treated also have improved drawing qualities without requiring special heat treatment. With the careful control processing, pickling and the 1200 prime ordnance pieces used the armed forces have een either considerably improved completely redesigned since the start the emergency. Loss tungsten supplies Namyung, China, due Japanese army drives will effect steel production here. Although imports were steady three years go, higher prices have encouraged ample production this country and Bolivia. have been made during the last two years only when unusually large mounts air cargo space have been available. Revelation that large group experimental fighters built for the Army Air forces not scheduled for quantity production emphasizes the fact that fighter now almost exclusively the jet field. Bell's and Vultee's all magnesium are relegated the have been" class, although postwar possibilities for the midget design are mentioned. 4 Boron Machinability and Hardenability Tests the influence boron medium carbon resulphur- ized open hearth steel indicate increase hardenability percent, and, anticipated, impairment percent more machinability. ° HARVEY Metallurgical Engineer, Monarch Steel Co., Indianapolis, Ind. purpose this investiga- tion was ascertain the effect boron the machinability and hardenability free machining steel. The base composition this steel follows: Per Cent Low Low The number the heat used was 52509. The ladle analysis this steel follows: Per Cent 1.49 Two ingots were treated with ferro- boron. Ingot “A” which showed 0.0020 per cent boron graphic analysis was 19/16 in. bars which were later die- drawn 1.512 in. diameter. Ingot “B” which showed 0.0024 per cent boron spectrographic analysis was rolled into 21/16 in. bars. Material from random untreated ingot was rolled into in. diameter ‘bars and subsequently die drawn 115/16 in. diameter. The grain size the steel without boron was found the Shep- herd method. The boron-treated ma- terial showed grain size. Jominy end quenched hardenability 52—THE IRON AGE, February 15, 1945 tests were done the Monarch labo- ratory the untreated steel and materal from Ingot “A.” The tests were machined from full sized bars and not normalized. had been previously found that this steel seemed have better hardenability when not normalized. These tests were made quenching and tempering the specimens before grinding and running the hardness traverse. This technique was used has been found give more ac- quenched hardenability test steel, heat 52509, non-boron- treated; 0.44 1.49 Mn, 0.016 0.227 0.06 Si, 0.02 Cr, and 0.01 Ni. Grain size Quenched 1550 deg. and tempered. 1200 1100 900 800 700 500 350 20.5 30.5 17.5,18 41.5, 41.5, 48.5, 51.5, 1.5 41, 42, Ot 11.0 9.5, 10.0 Equivalent hardness center round bars quenched still water, bar € | q | | H | 0 3A6| 17 21.5 26 27.5 3A6| 35, 36.5 39.5 43 45.5, 48.5 yy, | 15 18.5 21.5 22.0 4, | 28.5, 30 30.5 35 33.0, 36.5 ; 3 | 13 17.0 20 20.5 22.5 . 24 27.5 25.0, 27.0 a, | 13 16.0 19.5 19.5 | 22.0 23 25.0 23.5 ae 5, | 12 14.5 18.0 18.0 2 21.0 21 24.0 22.5 ; 34 | 11.5 14.5 17.0 17.5 | 19.5 20 22.0 21.5 ; Y% | 11.0 13.5 16.5 16.5 Ye, | 18.0 19 0 20.0 * 1 9.5 13.0 15.5 16.5 1 17.5 18 0 18.5 1y%, | 9.0 11.0 14.5 15.0 % 16.0 15.5 5 16.5 14 | 8.0 10.0 12.0 14.5 1 i; 13.0 14 0 14.0 1% | 6.5 8.5 11.0 12.12 1344 12.0 12 5 12.0 : 2 5 7.5 10.0 11.5 2 11.0 10 0 a labo- full had steel ability before rdness sed ac- curate picture the hardenability. Results these tests are found Figs. and Fig. shows the results Jominy tests run another laboratory. Ma- terial used these tests was forged approximate size, machined into specimens and then normalized before quenching. can concluded from the charts that the Grossman ideal critical di- ameter for the untreated steel about 1.6 in. and for treated steel 2.1 in. might also stated that the untreated steel will harden through per cent in. round and oil in. round. The boron treated steel will harden through water 1.4 in. round and oil 0.85 in. round. The ideal critical diameter computed from grain size and composition for the untreated steel was 1.44 in. and for the boron-treated steel (ingot was 1.74 in. The untreated die drawn steel 115/16 received draft 6.1 per cent. was stress annealed hardness 217 BHN. The boron-treated steel 1.512 in. diameter was also reduced about per cent drawing. The hardness produced stress annealing this steel was also 217 BHN. Machinability tests were made the University Michigan under the Boston, These tests were run dry. The re- sults were plotted tool life vs. cut- ting speed surface ft. per min. The tools Red Cut Superior (18-4-1) high-speed steel with the fol- lowing shape: 8-14-6-6-6-15-3/64. This means the tool had deg. back rake, deg. side rake, deg. end relief, deg. side relief, deg. end cutting angle, deg. side cutting edge angle and 3/64 in. nose radius. second series cuts was made which tool was ground the shape 0-12-10- 2-15-0 that would fail pre- liminary way relatively low speeds when taking light cuts 0.100 in. depth and 0.00077 in. feed. Now quote from Prof. Boston’s report: “The results the first, rough- ing, tests are shown Fig. The circles represent the results tool life for particular cutting speed— other words for 200 ft. per min. speed, the tool life was found min. The straight line passing Equivalent hardness center round bars quenched still water, bar size,in. Equivalent hardness atcenter round bars quenched still oil, bar Distance from quenched end standard hardenability bar, FIs. 2—End quenched hardenability test for X1545 steel, heat 52509; 0.44 Mn, 0.016 0.227 0.06 Si, 0.02 Cr, 0.01 Ni, and 0.002 Ingot grain size Quenched 1550 deg. and tempered. 1200 Deg. 1100 Deg. 1000 900 800 700 Deg. Deg. Deg. Deg. 500 350 Deg. 17.5,17.5, 25, 24.5, 27.5, 27.5 33.5, 34, 38, 38, 44, 44, 44, 50, 50, 54, 54.5 17.5, 21, 30.5, 32.5, 37.5, 37.5 42, 43, 43.5, 46,5, 47.5, 19.5 32.0 43.5 48.5 28.5 34.0 44.5 53.5 16.0 23.5, 28.5 33.5 38, 39.5 45.5, 50.5 12.0 16.0 19.0 20.5 20.5 19.5 11.0 13.5 16.5 19.0 18.0 17.5 9.0 12.5 14.5 15.0 15.5 13.0 15.0 through these points has slope (n) 0.106. The cutting speed for tool life (C) 192. The cut- ting speed for 5-min. tool life 161 and for 30-min. tool life 132 ft. per min. The tool life for cutting speed 150 ft. per min. 9.8 min. shown the graph. The crosses represent the experimental data when turning the boron-treated bars. seen that the value only 182, the slope (n) slightly steeper 0.115, only 151 compared 161 for the non-boron-treated steel, and the tool life for 150 ft. per min. cut- ting speed only 5.3 for the treated bar compared 9.8 for the non- treated bar. These tests show conclu- sively that the boron treated bars the same Brinnel hardness, but instead grain size, not give cutting speeds for given tool life high the non-treated steel bars. “Tt has many times been observed that when taking light cuts, machine work, the machin- ability ratings have been reversed. Inasmuch was felt that was steel would machine higher speeds than the non-treated, second series tests using very light feed were run. The results are shown and zero back rake angle was simulate screw machine tools; the side rake was deg., and the side re- lief deg., corresponding commer- cial screw machine practice. The circles represent the data Fig. THE IRON AGE, February 15, 1945—53 ron- rain 350 54, 51.0, Equivalent hardness center round bars quenched still water, bar Equivalent hardness center round bars quenched still bar Distance from quenched end standard hardenability bar, in. 3—End quenched hardenability tests heat 52509. Untreated: 0.44 1.49 Mn, 0.016 0.227 0.06 Si, 0.02 Cr, 0.01 Ni, grain size Ingot "A": 0.44 1.49 Mn, 0.016 0.227 0.06 Si, 0.02 Cr, 0.01 Ni, 0.002 grain size Ingot 0.44 1.49 Mn, 0.016 0.227 0.06 Si, 0.02 Cr, 0.01 Ni, 0.0024 grain size Boron Tool life, min. 4—Tool life tests, dry, for 1545 steel, untreated and boron-treated. Depth cut 0.100 in., feed 0.0127 in. 1595 6/0 500 407 12.5 Tool life, min. 5—Tool life tests, dry, for steel, untreated and boron-treated. Depth cut 0.100 in., feed 0.00077 in. 54—THE IRON AGE, February 15, 1945 for the un-treated steel bars. The treated bars gave very erratic results, that instead indicating single line, they indicate band shown cross hatched. clear, however, that all points and the whole cross-hatched area the data for the boron-treated steels are below those data for the un-treated steel. Consequently, inferior from machining point view. “It was observed that the chips for the boron-treated steel seemed more continuous and not well bro- ken the untreated steel. The chip coils from the boron-treated steel were larger than those the un- treated steel when turned the same speed. 200 ft. per min. speed and feed 0.0127 in., the untreated steel gave in. diameter coil chips until preliminary failure, and then small in. diameter short coils hav- ing light blue color. The finish was fair but torn. “For the treated steel the chips were from in. in. diameter coils in. long near the end the test, but the start they were very long. For speed 175 ft. per min. the untreated steel gave in. diame- ter coils for about min., and then and in. long light blue color. The finish was fair, being burnished before preliminary tool failure, but good thereafter. “The untreated steel gave large in. diameter coil chips the start the cut, but gray-blue coils from long after the tool was cupped. 150 ft. per min. the untreated steel gave in. diameter coiled chips dark blue color, well broken up. The treated steel gave in. diameter coils first, but small broken-up chips the tool wore. For speed 135 ft. per min. the untreated steel gave uniform finish with small diameter blue, well broken-up chips from in. 1/16 in. diameter. Dark blue broken-up chips in. diameter resulted from the treated steel this speed.” The hardenability this free ma- chining steel was increased per cent the addition boron. This contrasted with per cent incre- ment the computed hardenability. was anticipated, the machin- the steel was impaired the addition boron. This impair- ment was about per cent the reg- ular test and went high per cent the high speed light cut test. a) - 56.5 59.0 59.0 25.5 25.0 24.0 29.5 31.5 30.0 20.5 18.5 15.5 200 2000 oO The sults, ingle cross all tched eated the for The steel un- same and eated chips then hav- was chips ter the very iame- then meter color. but large start from in. steel sofa The meter speed reated small chips meter. in. reated ma- per This incre- bility. achin- mpair- reg- per test. Welded Fragmentation Bombs output 8000 fragmentation bombs per day being achieved the Coolerator Co., Duluth, Minn., due ingenious adaptation special welding jigs and the use large electrodes which help speed the work. The bombs, are about the size baseball but require approximately 11% in. butt welding per unit fabricate. The bomb parts, various stages manufacture, are shown Fig. with the all-welded and painted unit ready for loading and installation fuse control and release, appearing upper right corner. The two pieces comprising the bomb casing shell are stamped and draw-formed from thick blanks 1010 steel. (Fig. left.) The two cupped and die-beveled parts are butted together, spot welded, then placed roller conveyor which carries them the welding operators continuous flow. The operator positions the unit horizontal welding fixture, Fig. which rotated the operator’s left hand. the work revolved the electrode held constant position for best down hand welding. changing from 3/16-in. 7/32- in. electrodes, welding speed approx- imately per cent greater was ef- fected. The rods used are AWS ‘E6012 classification. After welding, the bombs are moved second conveyor which carries them through water sprinkler for cooling, then grinding and buffing stands. From here the work travels the pressure testing jig, Fig. where the bomb placed cradle arm and held rigidly just below water level, while the operator lowers the pressure nozzle which equipped with rubber tip effect air and water- tight fit. About pressure ap- plied. The negligible number “leak- ers” encountered are easily reclaimed rewelding. battery eight 300 amp. Lincoln welders are used this job fabri- the 4-lb. fragmentation bombs. parts for welded fragmentation bomb various stages manufacture. Completed unit shown upper right. The in. blanks are seen the left. 2—Welding bomb rotating spindle fixture. Finish welded units foreground show solid weld around circumference. Central exhaust system removes fumes through duct over work. 3—Pressure testing apparatus used assure air and water tight construction bombs. Photos courtesy Lincoln Co. THE IRON AGE, February 15, 1945—55 Crushed Wheel Dressing Form Grinding Production and laboratory tests indicate that crusher dressed grinding wheel has faster and cooler cutting action and longer life per dressing than diamond dressed wheel. The time required dress the wheel greatly reduced intricate pro- files, due the simplicity the dressing operation. ° ° RICHARD MOSS Production Engineering Manager, Sheffield Corp., Dayton, Ohio ° ° ° Crusher roller dressing method producing formed contour grinding wheel which ticular advantages diamond truing many production and tool- room applications. Essentially this method dressing entails rolling accurately made annular form into the surface grinding wheel with the two held rigid mounting relationship each other wheel dressed this method may used any application where grinding wheels are logically applied products today’s engineers are made possible means abrasive wheel dressing for the grinding widely applied this country prior 1944. Final design and processing com- ponents critical combat items have been based crush dressing profiles hard material. Careful in- spection the process will show that machine tools which grinding dressing method should logically engineered and built with that use mind. and some cases where grinding wheels have not previously been com- mercially usable. The novelty dressing abrasive wheels crushing dissipates readily with the realiza- tion that the effective hardness grinding wheel largely result its high operating surface speed. crushed dressing the peripheral speed the wheel from 250 300 ft. per min. This method abrasive wheel dressing has been extensively used England and Europe and lesser extent this country recent years. this writing, one machine tool standard the American market engineered specifically for production with crusher dressed wheels. was made the Sheffield Corp. which also has other machine tools process and design for manufacture. Careful examination the basic elements wheel crushing practices shows that the method has very few limitations this development stage. many types work, already presents much faster and less ex- pensive means performing grind- ing operation. The IGS. Standard deg. thread form crusher without coolant grooves. Removing first thread ribs crusher permits removal first imper- fect thread part during grinding thread. (B) Special crusher used dress wheel for surface grinding turbine blade root form. (C) Special crusher dress wheel grind form can sealing roll. Special crusher dress wheel grind ball race. 56—THE IRON AGE, February 15, 1945 > Ch inding com- result speed. pheral 300 wheel used ountry one andard been duction was also process basic ractices few stage. already less grind- produc- lant per- ress tion some intricate parts possible only with use method. wide variety both production results and laboratory tests shows that crusher dressed wheel has faster and cooler cutting action and longer life per dressing. The time re- quired dress the wheel greatly reduced intricate profiles, due the simplicity the dressing opera- tion. Grains Left Sharp examinations wheel surface structure after crusher dress- ing reveal the presence greater number sharp cutting points edges than diamond dressed wheel. Examination the surface the same wheel after diamond dressing reveals the presence flats which may truncated grains grainbond masses. This condition may explain the experience frequently noted production work that crusher dressed 220 grit wheel will cut more freely than dressed wheel 150 grit the same application. The absence these flats the periphery crushed wheel may also have the effect increased chip clearance and cutting tool relief. This belief supported measurements which show pressure crusher dressed wheel the work less than half that exerted diamond dressed wheel under otherwise identi- cal circumstances. the area wheel and work contact q permits grinding forms threads from the solid hardened stock with- out the softening effect frequently encountered sueh operations. Choice Wheels this writing, the best results dressing have been ob- tained with aluminum oxide wheels cut, resulting numerous flat surfaces. fine very fine grain size, medium grade and structure, with vitrified bond. Limited experience indicates that change silicon carbide grain with other wheel specifications re- maining approximately the same can made where that abrasive re- quired. The resilience plastic and rubber bonds present precludes their successful use with crusher dressing. The grinding wheel face width the wheel spindle mount such wheel and take wide facing cut without distortion. likely any case that the pressure exerted deflect the wheel spindle during the crushing operation will exceed the pressure the wheel the work ressing, grains are broken away instead cut, leaving sharp edges. (Right) diamond dressing, grains are often during the grinding cycle; the amount this pressure can measured, but will vary with wheel and crusher diameters, wheel width and hardness, profile being impressed the wheel, use coolant, and other lesser fac- tors. therefore necessary for the user determine, sometimes ex- periment, whether desired wheel face width can successfully used the application this dressing method machine not specifically constructed for such use. many cases wide wheel face will require longer delivery time from the wheel manufacturer who may have problem obtaining uniform density wide-face wheel ap- proximate specification. result Sheffield thread and form grinder, showing work head and wheel head. Note rigid mounting crusher slide with respect wheel spindle. Auxiliary driving motor for crushing speed wheel spindle may seen background. Upper portion wheel guard removable for crushing operation. THE IRON AGE, February 1945—57 | | 5 | LOSE-UP crusher roll and wheel dressing engagement. The grinding wheel serves driver speed approximately 300 surface ft. per min. variations density, dressing time would not appreciably influenced, but different rates wheel break- down may require more frequent ance. variety simple approaches may taken crush-dress abrasive wheels, using standard grinding ma- chines suited flat circular work. Factors which are readily determined basic include the following: The wheel must reasonably well suited crusher dressing. The wheel spindle and crusher must sufficiently free from deflec- tion relation each other assure wheel contour within ultimate toler- ance requirements. The wheel and crusher must roll together the reduced speed re- quired the operation. The form produced must within the profile limitations which apply this method wheel dress- ing. thread and form grinding machine with the entire mechanism for crushing, including low speed wheel drive for the crusher dressing cycle, built integral part, offers interesting comparison with typical converted machine tool. Multi-Rib Thread Grinder This machine primarily designed for the production grinding stand- ard thread forms—American, British, metric—with crushed grinding wheels. The width wheel, 58—THE IRON AGE, February 15, 1945 hard soft steel non-ferrous ma- terial provides means grinding the full thread form the time re- quired plunge the wheel depth, ordinarily one-fourth one-third revolution the work, and then make one full revolution the work form depth. comparison with con- ventional single-rib thread grinding this provides the speed and cool cut- ing the crushed wheel, well the forming much in. thread length slightly over one revolution the work. Conversion conventional single- rib thread grinder crushed multi- rib through grinding introduces the problem rigid crusher mounting the work position, the regular dresser position, improvised bracket mounted some fixed rela- tionship the wheel spindle. There the problem providing low crushing speed the wheel crusher, either which may serve driver. This may achieved through auxiliary drive the wheel head, hand cranking, driving the disconnected wheel its spindle through the workhead (with lead traverse disconnected) with the crusher mounted the work position. the wheel spindle and other ele- ments the machine have the strength carry wide face wheel plunge cut, usable results may achieved any approach which employs combination the ele- ments listed. The same specific crusher dressing grinding machine mentioned above offers facilities for variety an- nular form grinding jobs, ranging from reproduction crusher rolls for its own use variety cir- cular form tools, forms for gages, diesel injector plungers, parts for hydraulic mechan- ism and numerous others. The same features rigid wheel spindle and rigid crusher mounting make for maximum accuracy wheel contour and parts ground. Production advan- tages are obtained with the part con- tours preformed, but shallow con- tours the economy such practice doubtful since the rate stock removal such that the full form ground from solid stock comparatively short cycle. Any standard cylindrical grinder may converted with varying de- grees success for using crusher dressing for annular work. The same elements mentioned regard thread grinding must observed expected that greater operator skill will required the converted machine, and that any considerable degree improvisation crusher- dress will reduce accuracy result. The conversion standard grind- ing machine crusher dressing pre- sents two major problems any ap- plication: necessary that com- parative rigidity crusher mounting determine whether the reduced speed used crushing will obtained having the crusher roll drive the wheel having the wheel drive the crusher. Wherever possible, pre- ferable have the wheel drive the crusher for the reason that torque rotate the freely mounted crusher ordinarily less than needed rotate the wheel spindle assembly and drive. Elements Crusher Design Crusher rolls for multi-rib thread grinding are made with annular ribs the exact thread profile desired. The number ribs the crusher may exceed the width wheel face, permitting the crusher used two positions and thus increasing its useful life. Crusher rolls for annular forms are subject much greater variety. Ob- servation the action crusher rolls rolling with wheels dressing and examination rolls and wheels for wear afterwards leads estab- lishment certain practical limits design for such rolls. These limita- tions may make economically sirable use several crushers for production one wide form leave stock crushing for subsequent removal with flat wheel straight portions the form. simple rules g! | int ca eri ing pre hol dia per cor unting ary speed ned the ive the pre- ive the rque rotate drive. ign thread ribs desired. crusher eel face, used asing its orms are ety. Ob- dressing wheels estab- limits ically de- shers ubsequent straight nple rules can set control these choices, and some cases actual trial best. The factors listed succeeding para- graphs are based actual experi- ences and are meant point out those elements design which in- fluence crusher and wheel life most. The crusher diameter most com- monly used around in. smaller diameter will operate with pressure and offer less wearing sur- face. larger diameter will operate with greater crushing pressure and offer greater wearing surface. De- pending probable service require- ment, the rolls may made soft hard carbon alloy tool steel. High speed steel commonly used material. Limitations Discussed comparatively large difference two diameters the same crusher profile produces similarly different diameters wheel profile. The wheel and roll running full engagement will probably roll one the diameters and slip slightly the other diameter. some cases, may desirable make two crushers crusher two sections profile for use two positions reduce crusher wear. square shoulder the part and crusher, and similarly the wheel, presents surface which has only wiping rather than crushing action the engagement the two mem- bers. The frequent requirement for grinding annular slot with both motor driven roll unit for application reciprocating table type surface grinders. sides exactly deg. the axis troublesome with both crusher and diamond dressing because the wheel must cut away near the depth the slot each dressing order restore the width rib required the grinding wheel. The minimum fillet and minimum external radius which are com- mercially practical grinding with crusher dressed wheel are around 0.003 0.004 in. general, any production form which permits use crusher dressing within the three limitations cited above can ground with the use crusher dressed wheel held com- mercially close limits without the need for added finishing operations the work. Flat annular forms may produced with equal effective- ness. Retouching produce clearance angles form tools, straight outside diameters circular forms, and the like may desirable some appli- cations. Many potential applications for crushed wheel grinding await de- velopment machines ranges capacity suited their problems. Diamonds Impregnated Carbide Speed Wheel Recess HEEL dressers made with small commercial diamonds set into matrix Carboloy cemented carbide have made possible consid- erable saving time and money one Detroit’s largest aircraft en- gine plants, where they are being used true-up recesses finish grinding wheels employed grind the aircraft cylinder sleeves. When conventional single dia- mond dresser was used for the recess- ing operation—which necessary order that the grinding wheel may produce sharp corner the bottom the cylinder sleeve’s flange—the holder had ground flat and the diamond lapped the stone would Perform the dishing-out operation correctly without the holder touching the edges the recess when swinging through are. The Carboloy diamond-impregnated the other hand, contains particles distributed through- out the matrix, thereby insuring that least one more the stones will contact with the grinding wheel all times the holder swung through small Moreover, new cutting faces are presented the abrasive wheel layer after layer diamonds are reached and exposed, due the gradual wearing away the carbide matrix. Hence, lapping and remounting are needed. Reports from the former automo- tive manufacturer’s grinding depart- ment also indicate that these dressers lower the cost per wheel dressing the average job and successfully stand abuse which would ruin single dia- mond dresser. THE IRON AGE, February 15, 1945—59 red skill verted erable usher- result. grind- pre- ap- com- | | enameled articles such stoves, refrigerators, dish pans, in- which the enamel fused sheet- steel base, has generally been nec- essary until very recently deposit and fuse first the steel layer enamel comparatively high fusion point, known the ground coat, and apply the finishing white coats, normally lower fusion point, top it. .The ground coat has been nec- essary chiefly for two reasons, first promote adherence between the glassy enamel and the steel, and second prevent the appearance blisters, black specks and other defects the the production white vitreous surface. Adherence ordi- narily accomplished through the me- cobalt oxide the ground- coat composition, which promotes the formation the correct oxide coating the steel dissolve in, and unite with, the enamel glass. This oxide, however, gives dark blue color the ground coat, which course help forming the pure white finished surface obtained subse- quent enamel coats. Blistering vitreous enameled surfaces steel chiefly due the evolution gas from through the enamel while cooling from the fusion temperature, but the exact nature and source the gas have not been unanimously agreed upon. One explanation that sults from reaction between carbide the steel and oxide the enamel, producing carbonaceous gases, but other theories involving hydrogen have been proposed. fusing ground coat the steel first womparatively high temperature, most the gas generally evolved that time, that subsequent layers the white cover coats, fused lower temperature, may solidify free from gas. this way the use ground coat usually protects the cover coats white enamel from blistering “re- boiling,” and without the ground coat smooth white enamel coatings could not previously obtained. pure iron sheets entirely free from carbon base for vitreous enamels the source many defects due the evolution gases would probably eliminated, and one reason for the necessity 40—THE IRON AGE, February 15, 1945 New Titanium Steel For ground coat might longer exist. possible, however, convert the earbon steel more stable form, that does not react with oxides the enamel coatings form gas and blisters. This has now been done, actual commercial practice, add- ing titanium the steel the ladle the extent least five times the carbon content, and steel made this way has been found not produce the usual boiling blistering enamel coatings fused it. This presumably because all the carbon carbide, which more stable the enameling cycle than iron carbide. Theoretically four parts weight titanium are required combine with one part carbon, but prac- tice more than this proportion ti- tanium required because some may occur oxide, nitride sul- phide. With 4.5 times much tita- nium carbon, more, steel (or iron) found acquire several ad- vantageous properties. does not then have well-defined yield point, even the annealed condition, and not susceptible any kind strain- aging. This has been fully reported paper* and since the publication that paper, which dealt exclusively *“Strain Aging Killed Low-Carbon Steel, with Particular Reference the Effect Titanium,” published 1943 the A.S.T.M. Vol. the Proceed- ings, 521. with laboratory melted steel bar form, the titanium steel made with particular trouble several steel mills fully commer- cial scale, and rolled into entirely satisfactory sheets for enameling. Several methods have been used successfully for making the steel basic open hearth plants. All are based complete deoxidation the steel with aluminum prevent excessive loss, oxidation, the titanium added. One method involves adding low-carbon titanium alloy, containing aluminum, the steel being poured into the ingot molds. This best done large ingot, where the steel can poured fast with considerable turbulence the mold. The alloy may added means trough resting the edge the mold, and the addition should made gradually while the mold filling. There must sufficient tur- bulence mix the cold alloy oughly into the steel, since floats the surface will washed the sides the ingot, giving poor re- covery and serious defects the rolled slabs. better method add the tita- nium the ladle. obtain good re- covery titanium this way, necessary deoxidize the steel first with aluminum (silicon will riot do), and prevent minimize contact the titanium steel with the oxidizing open-hearth slag. This most tion steel sheet with 3.3 tio, etched first with nital attack the ferrite daries, with boiling dium picrate blacken cementite. 500 diameters. : re | Ww fil as | al 2 Ww la Vitreous Enameling ° ° ° COMSTOCK WAINER Titanium Alloy Mfg. Co., Niagara Falls, ° ° converting carbon steel more stable form with heavy additions titanium does not react with oxides enamel coat- ings form gas and blisters. With certain precautions one-fire finishes are practicable. readily accomplished tapping the heat the usual way into one ladle, where deoxidized with aluminum, and then pouring through large irely nozzle into second preheated ladle where the low-carbon ferrotitanum added. The stream from the first used ladle should moved around while expected deeply piped unless filling the second one, wash hot-tops are used normal killed- the ferrotitanium, which thrown Steel practice. possible. slag should permit- High Titanium Recovery ted flow into the second ladle, but The recovery the added titanium alloy, lime cover some similar material the finished steel has varied be- should used top the steel for tween and per cent these heat insulation. three methods, with the double-ladle ingot, only one ladle can used, giving the best results. The preliminary aluminum deoxidation titanium alloy use probably can effected the furnace spout, well-known per cent alloy, con- with the ferrotitanium added the taining about per cent titanium, ladle before the slag starts flow, per cent aluminum, per cent silicon and the slag should then not per- 0.05 per cent carbon. Other avail- mitted run out top the ladle, alloys either have higher melt- tur- which taken away from the spout point and dissolve the steel when the slag appears. Some cold slower, are lower titanium hed over the ladle for heat insu- The amount titanium added re- lation and chill and dilute what toa given heat depends the carbon the slag flowed the steel before since this steel must have the ladle could moved. The steel 4.5 times much titanium dissolve the ferrotitanium quickly, for the titanium-carbon ratio and the tap-hole should small even slightly low, the quality may that the slag does not start flow too better than titanium all do), had been used. the other hand, Titanium alloy steel made there excess titanium, even fully killed, and the ingots may 12, the quality not materially af- fected, the only difference being increase strength and stiff- ness. safer then aim for excess titanium rather than risk wasting what titanium used having slight deficiency. make this steel with about 0.04 per cent carbon. This requires least 0.18 per cent titanium, preferably about 0.20 per cent allow for slightly higher carbon some parts the heat. Assuming per cent re- covery, 1450 lb. per cent ferro- titanium would needed for 100 net ton heat. Although this may seem like pretty large ladle addition, has been used repeatedly the meth- ods outlined above, even exceeded, with failures date. lower carbon than 0.04 per cent aimed for save titanium, the time and the furnace may prove more costly than the alloy saved. Aluminum for preliminary deoxidation these ti- tanium heats has been used the extent about lb. per ton. Sili- con should kept low, not more than what acquired from the ferro- titanium. Manganese has generally been used the extent 0.35 0.45 per cent, but could probably lower since titanium will serve the purpose manganese preventing hot-shortness due sulphur. The re- covery the manganese added practically complete this very highly deoxidized steel. Structurally this steel consists ex- clusively ferrite and titanium car- bide, which occurs fine angular crystals indiscriminately through the ferrite grains. The fer- rite probably differs from that or-' dinary low-carbon steel ingot-iron, however, holding practically carbon solid solution, titanium car- bide being very much less soluble than iron carbide ferrite. proc- essed usual sheet strip mill methods this steel may tend rather coarse-grained, but normal- THE IRON AGE, February | | | | | | } | } } | } | | | | | } | | | | | } } } | | | } | } } | } { | | | | { izing not over 1650 deg. the fer- rite grain size may held No. finer. Fig. and herewith illus- trate the difference structure be- tween two steel sheets, made from the same heat and processed the same way, but with different titanium con- tents. One with only 3.3 times much titanium carbon seen contain some massive cementite well ferrite, while the other with titanium-carbon ratio about shows only ferrite grains, which are coarser than Fig. Tensile tests these cold-rolled sheets after aging gave the following results, each averaged from eight specimens: Titanium-carbon ratio ........ 3.3 8.1 Yield strength, 0.5 per cent off- Yield ratio, per cent ......... 82.9 Elongation, per cent in... The load-deformation tained testing these two steels are illustrated Fig. where the char- acteristic absence definite yield point the higher titanium steel obvious. These specimens were aged for about five weeks room tempera- ture, after the final temper-pass the mill, well for hour 450 deg. before tensile testing. The low yield strength, gradual yielding and high ductility the higher titanium steel are marked ad- vantages for cold.forming. This was mentioned the discussion the ASTM paper referred above (Proc. ASTM., Vol. 43, 544), where the superior drawing quality the tita- nium steel was reported. The drawn cups appearing Fig. illustrate the difference drawing properties the two steels, with less than, more than, the critical titanium-car- bon ratio, revealed the Boulger- Dahle cup-drawing test. The latter steel, illustrated at.the left side Fig. formed perfect cups from disks in. and 11/32 in. diameter, while the other steel failed with disks small diameter in. and 3/16 in. The Rockwell hardness these sheets was about for the lower- titanium steel containing some ce- mentite, and about for the higher- titanium steel with carbon not combined with titanium. The very excellent drawing quality this new titanium sheet steel has been amply confirmed numerous other tests made drawing difficult shapes with sheets from various sources. This one its most useful characteristics base for enamel- ing, since many enameled articles must first cold-drawn, and the best eold-drawing deep-stamping steel previously known not particu- 62—THE IRON AGE, February 1945 815 larly good enameling quality. The ti- tanium steel does not require any spe- cial heat treatment processing provide good properties, since has low yield strength, definite yield point and high ductility practically all conditions. Another property this new steel which useful enameling its stiffness resistance sagging enameling temperatures. Therefore, thinner gages the titanium steel can used for large enameled shapes, without risk excessive def- ormation when the enamel fused. The difference enameling quality produced increase titanium content amount exceeding the critical titanium-carbon ratio illus- trated the sample enameled panels the background Fig. These were produced firing cover-coat enamel directly steel, without any ground-coat. The blistering characteristic the results with all previous enameling steels when treated this way exhibited the right-hand panel with tita- nium-carbon ratio only 3:3. The left-hand panel, with titanium-car- bon ratio however, shows sur- face with only single white coat free from defects ordinarily ob- tainable only with two three coats. Obviously important advantage enameling costs obtainable this way, since both time and materials are saved. From vitreous enameling stand- point, the steel described above may used for one coat white work which the ground coat eliminated, providing certain precautions are taken. The processing the parts Typical load deformation diagrams titanium sheet steels. Both specimens aged 450 deg. after rolling. the pickling and dures also require careful control. Metal Finishing Operations possible, all metal finishing should completed before pickling. The following metal finishing opera- tions not affect the enameling properties the titanium steel ad- versely with respect black specking and blistering: (1) Deep drawing. (2) Metal finishing with disk grinder. (3) Spot welding butt welding. (4) Roll welding seam welding. (5) Metal finishing with metal finish file. Metal finishing operations which adversely affect the surface enam- eled ware are: (1) Electric welding with rod. (2) Metal finishing with disk (3) Heavy gas wel