The Iron Age 1939-05-11: Vol 143 Iss 19

has ent. bids cal- ure, uip- ant, 1ons tory dis- ther in- with date ving Mare soli- nine for with ylor, ar- orts- Mare edule spare ation pject, bids and FRITZ FRANK President VAN DEVENTER Editor Managing Editor News Editor Editor Emeritus Machinery Editor Art Bditor Metallurgical Editor Associate Editors Washington Editor MOFFETT Resident District Editors CAMPBELL Pittsburgh Chicago Cleveland Detroit Editorial Correspondents London, England Cincinnati FRAZAR Boston Hamburg, Germany MEYER CHARLES Post Milwaukee San Francisco SANDERSON ROUNTREE, JR. Toronto, Ontario Birmingham Newark, N. J. St. Louia TURNER, JR. Buffalo Owned and Published b+ CHILTON COMPANY (Incorporated) Editorial and Publication Office Executive Offices Chestnut and 56th Sts.. 239 West 39th Philadelphia, Pa. New York, OFFICERS AND DIRECTORS MUSSELMAN, President FRITZ J. FRANK, Executive Vice-President FREDERIC STEVENS. Vice-President JOSEPH Vice-President GEORGE GRIFFITHS. Vice-President EVERIT TERHUNE, Vice-President WILLIAM BARBER, Treasurer JOHN BLAIR MOFFETT, Secretary JOHN H. VAN DEVENTER, JULIAN CHASE. THOMAS KANE, CHARLES BAUR, G. CARROLL BUZBY. P. M. FAHRENDORF BAUR, General Advertising Manuger DIX, Manager Reader Service Member, Audit Bureau Circulations Member Associated Business Papers Indexed the Industrial Arts Index. Published every Thursday. Subscrip- tion Price: United States and Pos- sessions, Mexico, Cuba, $6.00; Can- ada, $8.50; Foreign, $12.00 year. Single copy, cents. Cable Address, ADVERTISING Emerson Findley, 621 Union Bldg., Cleveland B. L. Herman, Chilton Bldg., Phila. H. K. Hottenstein, 1012 Otis Bldg., Chicago H. E. Leonard, 239 W. 39th St., New York Peirce Lewis, 7310 Woodward Ave., Detroit 239 W._39th St., New York D. C. Warren. P. 0. Box 81. Hartford, Conn RoBERT BINGHAM ROBERT MCINTOSH MAY 1939 How Help Win War Installing Modern Tool Crib Control Carburizing Today—Methods, Steels, Treatment Tooling for Job Lot Gear Set Production Industrial Applications Hydraulic Drives New Machine Tools Meet New Demands How Big Are Inventories? Program 43rd Foundry Convention the Assembly Line Washington News THE NEWS BRIEF Weekly Ingot Operating Rate Rate Activity Capital Goods Plant Expansion and Equipment Buying New Industrial Literature Just Between Two Products Advertised Index Advertisers Copyright 1939 Chilton Company 112 124 129 154 tal ace et, for ory 819 7 —| treet, and joint uring for Ave- 00,000 James as re pres ronto, ry ad- yment, assem: Consider Labor Costs When Buying Steel most jobs, shop labor costs are the biggest single factor—and they depend large degree the steel used. bars are too hard for bend- ing forming—or have hard spots break dull tools—if some shapes are not straight—or the case alloy steel the required proper- ties are not developed the first heat treat- ment—then costs, down profits. Purchasing steel that uniform and has the properties most desirable for your particular use Principal products stock for Im- mediate Shipment include— Bars, Structurals, Plates, Iron and Steel Sheets, Tubing, Shafting, Strip Steel, Alloy Steels, Tool Steels, Stainless, Babbitt, Welding Rod, 30—THE IRON AGE, May 1939 often pays big dividends the form decreased shop costs. You not have pay any more for this kind steel—so why not get it? For several years Ryerson has been building stocks these better, more uniform steels. Careful selection, checking, testing and inspect- ing assure the uniform high quality necessary for Ryerson Certification. Try Ryerson Certified Steels your hardest job—and check the labor costs. Many have told that pays. Joseph Ryerson Son, Inc. Plants at: Chicago, Milwaukee, St. Louis, Cincinnati, Detroit, Cleveland, Buffalo, Boston, Philadelphia, Jersey City. = q - 7 ~ | 7 Re 7 7 ... THE IRON AGE ... MAY 1939 ESTABLISHED Vol. 143, No. How Help Win War OLLOWING extract from page 593 Budget the United States for the Fiscal Year Beginning July, 1939, and Ending June, part the appropriations made this act shall available for the salary pay any officer, manager, super- intendent, foreman other person persons having charge the work any employee the United States Government while making causing made with stop watch other time measuring device time study any job any such em- ployee between the starting and completion thereof, the movements any such employee while engaged such doubt, since much emphasis being put war preparedness, this was kept mind formulating these budget restrictions, which there- fore are intended help win war necessary. And, course, know that the matter industrial preparedness supposed quite vital for war winning. What applies men behind the lines should apply equally: well those front lines such matters military effort and discipline. There- fore, step toward winning the next war suggest that item such follows included any future war appropriation: enlisted soldier the United States Army, time war, shall required fire more than three shots enemy take more than three pokes him with bayonet any one working day. Said working day shall restricted six hours with overtime and the working week soldiers active ser- vice shall hours. Double quick time prohibited marches and there shall regulatory supervision the movements soldier employees the United States either drill recommend this suggestion the attention those legislators who were responsible for the budget restriction quoted our opening paragraph. would help win war—help the other fellow win it! | } A 7 7 j ais we -&§ u . | q 7 Strength with lightness makes for lower cost wherever materials must moved Because users demand it, the manufacturers against breakdown with fewer repair bills. excavating equipment are constantly improving Inland Hi-Steel easily formed and welded. Itis designs get lower, and still lower, costs for many leading makes construction equip- moving earth. ment, well trucks, tractors, freight cars, etc. this end, Inland Hi-Steel replacing heavy You may not build any these, but your castings and carbon steels, eliminating tons product must handle payloads for profit, you'll dead weight. Inland Hi-Steel combines high ten- find competitive advantages the use Inland sile strength with weight saving—faster digging Any Inland engineer will gladly explain speeds with lower operating costs—protection them. Write for Bulletin No. 10. SHEETS PLATE BARS PLATES STRUCTURALS PILING RAILS TRACK ACCESSORIES REINFORCING BARS aste 7 7 a wer ved uip- etc. your land many years most industrial plants, the easiest way for man kill time has decide needs new drill, brake tap, think mistakenly that another gage necessary addition the one already has. then strolls leisurely the tool room window, where the game time killing begins, usually company with half-dozen more his fellow-workers, who also are wise this on-company-time rest haven. Lately, however, alert and progressive companies have recognized the inevita- ble delay and confusion resulting from old-fashioned control tool cribs, and have installed such company the Falk Corp., Milwaukee, makers speed reducers, gears, flexible couplings, large marine turbine and diesel engine drives, use the words Paul Knowles, production engineer Falk, who was charge the tool room improvement project, the chief reason behind this desire set modern system control “sloppy appearing, crowded tool with too many men waiting served and sense confusion existing throughout.” addition, in- frequently One ROBERT BINGHAM Western Editor, The Age checks were lost and confused, ex- records tools available were kept, tool authority was not centralized, and the tool purchasing program was in- efficient and wasteful. must stated the outset, that the above condemning statements are not applicable only Falk before its tool room was improved, but all tool cribs all plants where uni- fied, controlled plan followed. The most common old style system the brass check plan, which was use Falk before the renaissance. The first step the modernization was clean out the old tool room, and general check-up was made remove all obsolete and unusable tools. The shop canteen which operated along with the tool room was removed shop store open only certain hours during each shift. Jigs and fixtures rated separate ment was decided make use tool system devised the McCaskey Register Co., Alliance, Ohio, the necessary control equipment under this scheme was purchased. addition existing facilities, two Lyon Metal Products Co. special storage bins, ft. long in. deep in. high, back back, were purchased also and permanently placed, space thus being provided for rearrangement. Mr. Knowles points out the convenience having empty bin available. Moves can then made rapidly and are accompanied minimum All tools were rearranged with regard type, accessibility window, and other factors. Placing grinders and other equipment was since the repair work incorporated within the enclosure the crib proper. After the physical work rear- ranging was completed and recheck made see that tools were all logi- cally placed sequence size and type, the crib was allowed run few weeks with the new arrangement obtain familiarity and uncover any weaknesses new ideas. Some tools were found unnecessary this time and were removed. All bins were beginning the lower left hand cor- ner increments for each shelf. Shelves were considered in. apart, this being close they can placed conveniently. The lowest shelf, for example, was numbered 8000, the next 8050, etc., for the 8000 section. 3-ft. bin opening cannot practi- cally separated into more than divisions, hence one section carrying number such 8000 may consist many three bins. Shelves verti- cally may spaced any multiple in. without disturbing the num- bering setup. Shelves may added THE IRON AGE, May 3 _ ; J i 7 7 7 BARS removed will and numbers are always available. Falk, numbers are allowed horizontally for one wide bin, section three bins wide being numbered 50. The numbering was started one corner and proceeded throughout the crib. Sections were blocked out and numbered thou- sands first and then the bins compris- ing each section were numbered shelf shelf for each tool the crib. Tool numbers four digits immediately in- dicate the bin location and the proper position the tool the bin. example, tool No. 8054 the 8000 section the first bin the second WASTE AND CLEANING RAGS departure from the McCaskey set-up. Sheets were made out for the attend- ant list the monthly turnover for each tool. When these data are com- plete, the sheets are referred the production department where the en- tries are transferred the tool turn- over report. The methods tool withdrawal, forms used for tool slips, broken tool reports, cabinets, filing systems, etc., were adopted directly from the McCas- key plan. full description the McCaskey system will not found this article, details are readily available from the McCaskey Register Co. and have been published elsewhere production department for replace- ment. All the necessary material was system began, that concerned could familiarize with the equipment. The installation was big job, Mr. Knowles said, but was worth the time and effort. best results.” said, “the original planning cannot too detailed and accurate. The more carefully all the preliminary work done, the smoother the finished ma- chine will run when started. From what have seen many tool rooms attempting run with tems, find most failures partly #24000-FLAT BROACHES HUNG BACK 21000 MISC. DOGS |STUD DRIVERS ETC. TOOLS| AND PARTS LOCKERS FOR PECIAL TOOLS 19000 ROUND BROACHES PINS LARGE "MIKES" #35000 END #18000 #17000 #17000 #17000 CUTTERS END ENO END MILLS #8000 #8000 #8000 #9000 #9000 REAMERS DRILLS DRILLS REAMERS REAMERS LARGE "MIKES" LARGE McCASKEY CLIP FILE BOARDS #7000 #6000 SLEEVES DRILLS A A CHASERS CASKEY FILE CABINETS TOP BINS 30"HIGH shelf from the bottom, and the fourth shelf division from the left. This system numbering flexible every way. Other preliminary work included the making out tool activity contro) sheets consisting all tools listed alphabetically for easy reference. Mr. Knowles considers this the most im- portant work sheet the entire set- up. Inventory cards were made out and placed the McCaskey register cabinets. Falk does not use these ac- tually for inventory, but division point separate pink tool slips denot- ing tools out and returned. Inventory cards are card indexed the fore- man’s desk and are entirely under his jurisdiction. This the only major 34—THE IRON AGE, May 1939 MICROMETERS MISCELLANEOUS COUNTER WIDE WINDOW many times. Our purpose merely point out what one company has been able accomplish the use this tool crib control scheme. Briefly, however, the mechanics con- sist the use triplicate tool with- drawal slips, one kept the man his record responsibility, second charged against the tool, and the third charged against the man. When tools are broken, reports are made out and turned with the tool the tool room foreman, who checks the tool for scrap salvage and makes his deduction from his in- ventory record. The crib foreman has final authority Falk disposi- tion broken tools and requisitioning TAPS TAPS TAPS TAPS TAPS TAPS 34000 END LARGE DOGS efficient setups are due incomplete planning and lack careful attention preliminary detail.” The opening date for the new sys- tem into operation Falk was set for May 1938. Notices were posted prominently and all foremen were instructed turn all perish- able tools, wrenches, drills, taps, in- dicators, gages and the like April 29, Friday. Because the great con- fusion which would from trying clear all outstanding tool checks, tools were just dumped the crib window with all. According Mr. Knowles, “The quantity and variety tools turned was enormous. was revelation see what the men had | ] | | | | | | q | } | 7 — collected over the years. Tools long since regarded lost were returned. low estimate the number would and Sunday crib attendants worked placing tools the proper bins, sort- ing out worn and broken tools, and preparing generally for Monday morn- ing, which time the crib opened schedule. Falk now has well planned tool room, with every advantage being taken space, that the attendant will have unnecessary steps wasted time. All tools are indexed, numbered and well binned with crowding, and room for future expan- LEFT durable matting, made rug fiber impregnated with rubber, solved the floor problem. Its resiliency and com- fort added much the comfort the attendants. This product made the Bickett Rubber Co., Water- put control system across when sees you are willing cooperate with him and his men. gain his full confidence and support will win half the battle.” balanced inventory now avail- BIN No.8000 SECTION layout the re- vised crib layout the tool room the Falk showing general method num- 63/64 8502 8503 8504 8505 8506 ----- Solid reamers bering bins and contents there- of. This view shows the storage section only. RIGHT maps were made each bin after tool numbering and arrangement had been completed. These charts are kept hands tool supervisor production department for ready reference. They serve easy means making the initial inventory. Entries are made directly the chart colored pencil. Cross reference any other chart simple procedure. sion has been allowed, both quantity and type tools. obtain the above results its tool room, Falk considers the cost rather high. Mr. Knowles said, “In- cluding all equipment, bins, etc., this cost was about $4000. This was more than justified, correct and simple layout, neatly arranged possible, makes other handicaps easier. The morale the crib grew and real pride the crib created real interest the job hand. cannot too emphasize the necessity working out the details arrangement. Check lighting sys- tems carefully and provide necessary lighting. sure that crib ade- quately closed and locked. "he 8402 8403 8302 8303 8252 8253 8202 town, Wis., and highly recommend its use tool room, machines where oil not too prevalent. Gen- erally speaking, tool room foreman has excellent ideas what wants needs. will much 8404 8405 8406 8304 8305 8254 8255 8256 8004 8203 8204 able this tool room where none existed before. The broken tool report procedure places the responsibility for quantity tools directly the hands the tool room foreman. When files his copy the report, sends THE IRON AGE, May \ 8452 8453 8454 8352 8353 8354 8306 8152 8153 8154 on re red ing MONTHLY TOOL TURNOVER REPORT 1938-1939 PRESENT MINIMUM monthly tool turnover report, made out for each class tool alphabetical order, considered one the most important work sheets the set-up. The figures show the number times individual tool was withdrawn from the crib during any particular month. Minimum stock determined from these histories. TANDARD sheets similar this one were created for the engineering department. Attempts are made all times ad- just shop needs tools listed these sheets. this way standard- ization achieved and accumulation miscellaneous special tools 36—THE IRON AGE, May 1939 | | | | TOOL No. DESCRIPTION OF TOOL UN JUL AUY. JOLT. STOCK INVENTORY| NET 7 7 7 ¢ | | f ( 7 { ( | q q | the other the production indicating replacement when required. production department therefore daily informed breakage. After eight months operation the tool activity control sheets were used set minimum quantities tools These were determined consulting the tool room foreman and his file inventory cards. Reference was drawn, and the know- ledge the number required permit grinding, enabled him set reasonable number have This resulted reduced in- ventory. Gearing tools were cut from $4228 $2239, drills were cut from $9000 $7000, facing bars from $4080 about $1500, chasers from $6000 $3500, and end mills from $2800 $1600. These items indicate the gen- eral trend, which cannot entirely out because the full evalua- tion tools and the value inven- rory reduction has Perpetual Inventory Available perpetual inventory always ob- tainable through perusal the pink slips, since those placed ahead the inventory card the compartment represent tools check can thus instantly made the number tools existing any time. always known who has the tools which are out, and can readily determined how long any tool has been one man’s hands. Falk holds the tool room foreman fully responsible for the complete care, condition and quantity tools. all times the production department, which must consulted before can change records, layout, tool numbers minimums. pro- duction department with its records can all times check him any items requirements, and can, and does, check his minimums against tool movements and inform him raise lower these limits working conditions. Closer Control Achieved Some significant comparable figures have resulted from this close working arrangement. Quoting Mr. Knowles again, “Machine shop payroll, taxes, insurance and other overhead aver- aged constitute means com- parison with figures comparable several operations, show that these items 1938 were about per cent 1937. The perishable tool purchases 1938 were per cent 1937. This was accomplished eight months control. During this period, purchases were cut down, were using tools reach minimum throughout the period. Since this re- sulted dollar saving excess $50,000 for tools and supplies, can seen that the effect was well worth while. Purchases 1937 were 000 against $55,000 Tool standardization was suggested the setting minimums the basis tool movements. Accordingly, based turnover reports and inven- tory, standard tool sheets were created for the engineering department. most cases special tools were and are adjusted meet the standards, and the production department consulted for information tools not shown the standard tool sheets. Standardization tool purchasing another result, the establish- ment tool budget means arrangement with the cost depart- ment. This arrangement merely in- cludes the furnishing the cost purchases during the month, and the provision the production depart- ment cost record broken and worn tools scrapped during the month. Thus the asset value perishable tools carried the company books kept balanced, and since budget permitted. One the miscellaneous benefits resulting the ability determine which tools are needed continually certain work. these jobs the men are allowed keep the tools their possession and are charged with them directly. When man leaves the company, the company wishes check certain man, his record with the crib easily checked. The value those tools for which cannot properly count deducted from his pay check. cases where departments use cer tain tools day after day, the foreman held responsible and allotted cabin- ets provided with lock and key for storage. Under this arrangement, about 1000 micrometer transactions month have been eliminated. Thus far, Mr. Knowles says, foreman lost tool charged him manner. Standard Job Tooling The final step, now only the pre liminary stages, standard job tooling. “By this process,” Mr. Knowles said. “we hope combine the quired standard machined part drawing number. file record such standard tooling the tool crib will permit man draw all tools required standard operation one slip. This tooling number can placed advance the work and the man can obtain the tools re- quired before receives the draw- ing the job. This will materially reduce the filing work the crib and the number slips made out the man. this can achieved, feel have nearly perfect an- swer possible.” THE IRON AGE, May 1939—37 | < the subject selection the case depth used, might first mentioned that the depth penetration may anything the available metal section, course, sufficient time and active carburizing agent provided. However, glance May page 36) will show that the time required considerably length- ened when high penetrations are sought. Consequently, the majority work case-hardened depths 1/16 in. less, and rarely indeed more than 1/8 in. desired. Several factors must considered selecting the case depth limits, and the choice steel used must concurrently made. Probably the best starting point decide what the probable type ultimate failure will should be. failure will the end due abrasion, then the 38—THE IRON AGE, May 1939 OTARY-RETORT gas operation the plant the Cleve- land Tractor second point what wear force replacement. example, piece will longer function usefully when worn 0.010 in., then ob- viously there little value case much deeper. If, the other hand, the part will serviceable long there any hard surface left, then economical balance must original cost deep case and replacement cost. purely abrasive failure chanical loads the embrittling effect (due duced tough core) deep cases must considered, well the probable failure the piece by. bending shear after abrasion has considerably reduced the metal section. The rule Use the least case depth which will in- sure required original properties and reasonable, competitive service life. When the mechanical loads tered are severe and tion case depth, careful analysis must made the nature and tensity the stresses. Simple shear bearing loads are ordinarily easily and the case required nominal. When alternating compres- typically gears, sufficient case must provided that the resistance the the surface greater than the stress intensity. other words, the high endurance limit the hardened case must continue inwardly until the demands any sub-surface point. the stress increases from zero the neutral axis maximum the surface, while the resistance the core constant. the latter exceeded, sub-surface failure will re- sult. “Spalling case” service frequently due this action. The scratches, hardly needs pointed out, but must remembered that such effects are intensified hardened steels, and carburized parts are more easily dam aged than softer steels. All theoreti- cal considerations, the paragraph above, may nullified poor design machining. core notches, mind the possible reduction the hardened case grinding after burizing. Obviously, sufficient case must provided permit the neces- sary grinding—for finish warpage—that the final product still has the desired case depth and | 7 7 7 7 _ GORDON WILLIAMS Chief Metallurgist, Cleveland Tractor Co. ° hardness. Contrarily, may noted that increase case often produces increased warpage, that this method attack may unsuccessful. alternative is, course, reduce warpage better hardening practice, treatment. quenching dies fixtures may permit the dual economy shallower case When, usually necessary, cessive brittleness must avoided, the common rule leave least one- third unearburized, that is, the total case must not exceed two-thirds the section the thinnest point. low cases, often less than are used two decidedly different groups parts. washers, small tools, and similar parts when re- needed, but loads and wear are moder- ate. The second class work given shallow cases includes heavily loaded automobile gears; these, ever increasing proportion being gas carburized during the hardening treat ment, steel fair hardening quali ties being used, that the case simply the wear resistance, while withstand the expected loading. extensive grinding can permitted with such shallow cases. Case depths around 0.030 0.060 are very commonly used for moder- ately loaded parts such gears and Shafts; also for washers, gages, etc., must ground for finish, but are not heavily loaded service. The range 0.035 in. this, the second section two-part article, the au- thor deals with the selection case depth for any particular application and the selection types steel for carburiza- tion. the first section the car- burizing procedure was de- scribed, along with the various techniques used and results obtained. might well called the standard case important reason for selection this range seen examining Fig. 1700 deg., the usual carburizing tem- perature, about hr. required give this penetration. Consequently, fair opportunity given for all pieces mixed charge come heat and achieve fair uniformity carburizing, with reasonable assurance that none will below 0.035 and none far above 0.050 in. Case depths between 0.060 in. and 0.075 in. are specified only when severe abrasion expected, and good wear-life wanted, heavy- duty gears such truck tractor final drives, where stresses are very severe. Case depths above 0.075 in. are rarely required except for long wear- life abrasive conditions such special applications hard-sur- faced steel plate for armor safes. Selection Steel already indicated, choosing the steel used for given case-hard- ened part closely tied with car- hurizing method, case depth, and hard- ening treatment, and all these factors must simultaneously considered. available and useful. Nearly every problem will have solutions and economic manufac- turing considerations will govern final decision. CARBON will ordinarily preferred, because cost, when the distortion following water-quenching can tolerated. Core carbon content 0.10 0.25 customary, the lower range preferred for thin parts. Since carbon steels are shallow little can done toward improved core properties carbon alone. The low manganese plain tend toward non-uniform and the higher manganese range (such SAE X-1020) preferably em- ployed. Note that plain carbon steels can hardened just hard as, harder than, alloy steels (the same with when abrasion steels), only encountered, alloy steels may offer either advan- tage some disadvantages. small percentage chromium, manga nese 1.5 per cent, may for improve the hardening core properties the carbon steels, but water quenching will still used. ALLoy STEELS: When the properties required the core are higher than those given carbon steels, or, particularly when oil quenching must used minimize one the many alloy steels THE IRON AGE, May 1939—39 | be 7 is st | ro ol re- ies, 4 ers i the rect still containing per cent total alloy ing elements will selected. There are several possible choices here: The physical properties and working quali- ties the SAE 3100, 4100, 4600, 5100, and 6100 steels are quite similar, differences due design manufac- turing difficulties choice. will noted that all the above steels contain either chromium molybdenum both; these ele- ments are greatest value case hardened parts due their ability give hard case and good depth-hard ening, while nickel may combination improve toughness case and core. special type steel coming into widening only molybdenum alloying element but specially made give con- trolled hardenability carbon content usually somewhat higher than the preceding steels give desired core properties. There increasing use higher core carbon content with re- sultant higher physical properties steels this group, the case depth being decreased somewhat. machining and lower carburizing time give improved economy. selection suitable hardening treatment (usually direct quenching), good case and core properties plus low distortion may these steels. instances the expected service require- ments can met most economically one the simple alloy steels, but occasionally necessary use such steel 3312, 2515, 4815, containing per cent alloys. Excellent core physical properties can attained with these, but their high cost, well the more elaborate heat treatment often required, rule them out normally. Further, reten- tion austenite the hardened case damaging certain kinds ser- vice, especially when heavy rolling loads carried; the more simple alloy steels may retain considerable austenite after some treatments, and these higher alloy types prone such behavior. GRAIN or, better, resistance grain growth the carburizing tem- perature, usually specified mod- ern practice. coarser-grained steels harden better, have lower tough- ness, and tend distort more; the fine-grained are more tough, 1See “What About Grain Carl Shapiro, THE IRON AGE, March 23, March April 1939.—Ed. 40—THE IRON AGE, May 1939 readily hardenable, and show less dis- Since steel producers gen- erally offer choice grain-size range usually wise take advantage this specifying either coarse grain (McQuaid-Ehn test) cated the requirements. SELECTION HARDENING MENT: Again the other factors already 1315 Mn 1% per cent ......... 1345 2315 per cent .........1300 4615 1%, per cent. .1335 retention. mentioned must borne when selecting the heat treatment used harden the carburized case. summarizes the standard heat treatments graphically and principle features each treatment, while Table lists the standard car- steels with their points and the preferable heat treat- ments. Before discussing details these hardening processes, must em- phasized that prime factor ducing distortion case-hardening preliminary annealing the pieces either before during machining temperature higher than will used TABLE Standard Carburizing Steels and Heat Treatment Characteristics (Metals Handbook, 1939) Critical Points S.A.E. Case Ac,, Alloys Deg. subsequent treatment, car- burizing. Since the latter usually performed 1650 deg. 1700 annealing temperature 1750 customary. Sometimes steels are selected which will coarsen size at, say, 1750 1800 deg. and the annealing carried high enough cause this grain growth; machining facilitated, and later, reheating lower temperature restores the fine Preferred Quench- Tendeney Treatments, ing Retain Deg. See Fig. Medium Austenite 1605 A.D water Slight 5 per cent NaOH solution 1520 solution Slight 1440 oil Moderate 1420 oil Strong 1500 oil Slight 1465 oil Moderate 1435 oil Strong** air 1426 oil Strong** 1500 oil 1485 E,C oil Slight 1440 oil Moderate 1550 E,C oil Slight 1550 oil Slight 1475 F.C oil Moderate *All steels preferably grain size finer. +Acy of core will decrease as carbon is increased. **Spheroidization excess carbide subcritical treatment may used decrease grain size. any event, internal stresses must relieved annealing severe and irregular distortion may occur later treatment. Direct QUENCHING FROM CARBU- RIZING the most widely preferred hardening treatment (E, Fig. for the low alloy steels; oil quenching customary. This treatment prevents formation the carbide zone, thus avoiding major cause case brittleness. fine are used, direct quenching will give minimum distortion. the steel used has much tendency retain austenite, this treatment condi- | 4 | 7 | 7 | | Rest gr Rest gr Rest ‘ gr Rest “ co ate Ada Ada j 7 gre 7 | | | | | | tion; either control the tivity, negligible excess carbide will from carburizing, reheat- carbon content the case (see gas formed. ing, has been given. With the latter carburizing above) lower hard- treatment (D, Fig. 4), the ening temperature must used. The REHEATING CASE AND honored “double maximum core hardened the maximum. Core: the heating temperature toughness core and hardness case Direct quenching may followed high enough (C, Fig. 4), both case and are achieved, but with sacrifice core requenching from core will hardened, giving strong strength and with fairly large distor just above the critical point the but less ductile core, with somewhat case (F, Fig 4); better toughness brittle, hard case. This treatment the core, better hardness the case, widely used parts All case-hardened pieces and somewhat more distortion follow. hecause the balance between maxi- have considerable internal stress due the duplex nature the material, and any but the crudest parts should given draw treatment the maxi- mum temperature which will not ap- preciably affect the surface hardness suitable. Particularly the surface aid avoiding grinding cracks; carbide network present. easily performed with very satisfac tory results. The various factors time and temperature actual carbu- Rest adapted fine Refined excess carbide not dissolved. Unrefined; soft and ma- rizing, adequate supply active chineable. carburizing agent the desired type. adapted fine Slightly coarsened; some solution Partially refined; stronger and judicious selection steel, case erate steels. and tougher than (A). depth, and hardening procedure, must cess carbide favored; austenite re- strength control not difficult. ng** “tention promoted highly alloy Better combination steels. strength and ductility than (B). erate treatment for Refined; solution excess carbide Refined; soft and machine- coarse grained favored austenite retention mini- able; maximum toughness Wire Galvanized steels. mized. and resistance impact. tion minimized; file proof when carbon high. Marino galvanizing process Adapted fine Refined; solution excess carbide fair which has had five-year trial Fic. 4—Characteristics usual hardening treatments. (Metals Handbook, States and anada license sale through the office George Hart- ley, consultant, 311 Main Street, Wor- cester, Mass. this process many tons wire have been produced hypereutectoid zone pre- may fairly well removed from grain cleaning, pickling and galvanizing cipitate around the grain boundaries, boundaries. with any hardening entirely automatic process, and and its resolution may such treatment above the lowest possible may adapted cover wires and network leads brittleness the temperature, austenite retention pro- shapes with tin, lead, copper, red case. work must slowly cooled moted the steel contains much alloy other metals and for from carburizing, and the cementite content. allovs. network will too undesirable, then Production schedules are claimed the first hardening treatment must REHEATING FOR CASE ONLY, per- per cent faster than hot gal- ork sufficiently high temperature formed temperature just above vanizing, and production costs are oid permit re-solution this carbide the case critical point (A, Fig. 4), claimed being lower. This process quenching (C, Fig. which is, course, quite bit below said turn out product passing many alloy steels solution slow, the core critical and the excess carbide rigid specifications, and one mill that high temperature and consider- solution temperature. Excellent case England currently turning out sed able time must allowed. course, hardness follows quenching from this tons Marino galvanized high ten- carbon content has been held near range, but case tends brittle un- sile wire weekly for British Govern- controlling carburizer ac- less high quench, either ment agencies. THE IRON AGE, May PRODUCTION transmissions signed and built for truck and bus manufacturers and for the industrial field. The company also makes gears for special assemblies. live-speed transmissions. then added four- and eight-speed types. Despite the influx new designs, the shop and engineering department continue run smoothly. Employment not- able for steadiness. There are sharp peaks valleys the produc- tion curve. spite the fact that most customers release 30-day actual production runs remark- ably close the sales estimate projected three months ahead. make this possible, Fuller has done three things: has designed series transmissions which with simple gear changes can altered suit individual requirements; has equipped itself with highly flexible gear department, and has developed method gear design and produc- 42—THE IRON AGE, May 1939 GEAR SET tion that has eliminated headache. matter fact, all the 300 sizes and types active gears—and for that matter many the rest the 1400 gears—can produced with but sets tools, including four sets tools for and two spur cutters for close shoulder work. Gears are designed fit standard tools, standard cases, standard shafts. For instance, supposing some manu- facturer desired transmission with certain set ratios, all which except perhaps the third-speed ratio would covered standard Fuller model. that case, new set third-speed gears—operating same center distances the standard set—are worked out for the transmis- sion, changing the number teeth, tooth thickness, etc., fit the require- ment. These gears may not have—and probably will not standard pitches, but they are designed with true involutes and they can UT-AWAY view typical Fuller transmission. This shows helical and spur gears. Some trans- missions also incorporate herringbone gears. duced with tooling already Often change gear blanks necessary. Production deliveries speeded up, and costs eliminated. The gears may but they work perfectly. make such design flexibility pos- sible, last year gear department with the most modern equipment available. Basic steps the produe- tion gears consist hobbing, shaper cutting when shoulders are present, shaving, grinding the precision boring the bushings, burizing, lapping 100 per cent quiet test. The hobbers, are equipped for climb-hobbing. One the stan- dardized practices Fuller, inciden- tally, the shifting each hob pitch for each gears hobbed. This, together with climb- hobbing, largely credited with 7 & increase tool life some 200 300 per cent more. the hobbers the shapers, gears the gear shavers, which are the type. Alongside each shaver grinder. The shaver finishes the gear teeth concentric with the arbor centers and the outside diameter ground arbor. This assures that the o.d.’s are accurately concentric with circle. The operation important since gears are later located from the chucking for all subsequent hole grinding boring operations, such the Heald Borematic, Fig. for precision boring the bushings. further important requirement for accurate control the o.d. in- volved the engineering design the gears. When designing new set gears, each checked cal- culation see that the crossed-axis shaver cutter will not hit the fillet the root the teeth left the rough- ing tool and yet will cut deep enough that the gear shaved beyond the maximum entering depth the mat- ing gear. are engineering checks all gear designs. the design does not fall within this range, the gear design altered roughing operations are changed the operation sheét correct the con- dition before releasing the the shop for production. ANUFACTURE 300 sizes and types gears—including gears for standard trans- missions—is being accom- plished with only sets gear cutting tools Fuller Mfg. Co., Kalamazoo, Mich. The record books show total 1400 gear designs, any which the shop may called upon produce any time with- out major tooling revisions. per cent all gears are sent the checking department for lead and involute checking, Fig. The Mich igan involute checker, incidentally, special design, equipped handle gears with shafts in. between centers. The involute checker, furthermore, equipped with new tooth. The design such elim inate the necessity fine adjustments ment Fuller Mfg. Co. Ma- chines are Barber-Colman type equipped for climb hobbing. locating the finger relation the base diameter. One angle rack used for both spur and helical gears regardless pressure helix angle. Set-up time for the lead checker and the shaver (figured together) whether not cutters are changed. Lead checking handled regular production workers. simplify the operation, tables Johansson block combinations for the sine-bar setting the lead checker—for each size gear—are provided the checking All Fuller gears are carburized maximum life under heavy loads. Subsequent lapping gears carried pairs, without recip- rocation, special machines, Fig. These machines are built from spur gear testing machines equipped with hydraulic brakes (oil pumps with re- stricting valves). interesting fea- ture the handling lapping abra- sive. The amount abrasive circulation relatively small. carried small funnel reservoir, drawn off from the bottom and foun- tained the full width the gear, returning the funnel. After each pair lapped small measure full abrasive and oil (designed equal the amount used) added the funnel tank. This method control prevents sudden changes the com- pound and assures consistent lapping, THE IRON AGE, May 300 active gear types. 2—Michigan-860 rotary type gear shavers are used for finishing all Fuller gears. Before removing from arbors, gears are placed the Norton grinders the right and left the shavers for grinding the o.d. the gears. Only cutters are required shave has been tound. changeability gears secured. After assembly into transmissions, all gears are checked for quietness under load. Reason given for this that quietness gears greater problem trucks, for instance, than passenger cars, since the former are not heavily insulated for noise are pleasure vehicles. The noise problem trucks particularly. acute with overdrive gears. was largely obtain the quietest gears possible that Fuller selected gear shaving for the finishing operation. Since then has been found, however, that the shaving operation has ap- parently increased gear life, while being considerably faster and less cost- than either finish hobbing cutting. For the roughing operation, have been found highly satisfactory when followed shaving. The installation the new equip- ment Fuller, incidentally, credited with not inconsiderable reduction manufacturing costs, aside from the economies tooling costs effected with the gear design method. SSS « id gee : s\ — RIGHT IG. 5—A view cor- ner the production gear-checking showing Michigan lead and involute checkers. BELOW—LEFT 1G. 3—One the factors which con- tributes toward rapid change-over for the gear shaver the keeping record for each type micrometer readings across the locating pins provided the table the shaver. The arrangement such that in. micrometer reading equals ap- proximately in. adjustment lead. BELOW—RIGHT precision boring Heald Borematics finish gear bushings, the lo- cation from the o.d. the gear. previous operation the o.d. ground accu- rately while the gear still mounted the shaver arbor. THE IRON AGE, May 1939—45 re fe : the Methods and Equipment Industrial Power Transmission. ONTINUING the discussion hydraulic drives begun Chap- ter this series (Charac- teristics Hydraulic Drive Trans missions, THe Iron Ace, April 13, 1939), will interest this point quote the words the noted British authority this subject, Mr. Harold Sinclair, the differences hetween the two drive sys- tems now widespread use: “Owing the positive character the displacement (hydrostatic) type transmission, its characteristics are strikingly different from those the turbo (hydrokinetic) transmissions, and there considerable range applications for which hydrostatic gears are ideal, but for which turbo transmissions have little scope. particular one may mention steering gears, gun-training mecha- nisms, hydroplane controls, machine tool feeds, printing calender drives, and all applications low power requiring precise speed regulation over wide range torque and speed, and constant speed the output shaft practically irre- spective changes load. ‘Turbo transmissions are not generally suited for such purposes, account the turbine characteristic that the speed responsive changes load. this feature, incidentally, that permits the automatic variation torque with speed that useful the torque converter. Where the load the variable-filling (scoop-tube) type are not very rapid, such speed changes can corrected governor gear, but the natural characteristic broadly alternating current motor with vari- able resistance the rotor circuit. 46—THE IRON AGE, May 1939 simple. comprises merely mary shaft with its impeller, and secondary shaft with its turbine run- ner; there are fine running clear- heavily parts affected distortion. ances, “There wide field application which either the hydrokinetic the hydrostatic transmission utilized. regards variable speed drives, the efficiency the hydraulic coupling with its variable filling slip control definitely superior the high-speed end the range, but falls below that the hydrostatic type when working large speed the case fan cen- trifugal pump drives this unimpor- tant, since the load falls off rapidly with reduction speed and the actual small. the other hand, for con- coupling offers the convenience infinitely variable but gives advantage saving | | ° ° ° > = ABOVE American Engineering Hele- Shaw drive, operating Taylor stoker through chain drive reduction unit. LEFT 2—Oilgear variable dis- placement fluid power pump unit furnishes the operating power for this 500 ton Farrel- Birmingham metal formin press. power when running speeds. The hydraulic coupling offers advantages the shape light-load starting, limited stalling torque, and connection both the torsional senses; its outstanding feature mechanical sim- and smooth, vibrationless drive.” The illustrations reproduced here with are all fairly representative current hydraulic drive practice. Care- ful consideration these applications will show that Mr. Sinclair’s summary essentially fair and logical Hydrostatic Type Application Fig. shows the fluid motor end only American Engineering Hele-Shaw drive connected means chain drive the driving shaft large stoker. Such stokers ciently over wide range burning rates, from banked condition several hundred per cent rating. Speed ranges high with accurate control any intermediate speed, may under such circumstances. ° The variable displacement pump unit the hydrostatic system, used without the corresponding fluid motor, has wide range applications where the driven mechanism requires linear motion instead rotary mo- tion. One the most familiar ex- amples is, course, the hydraulic press all its varied forms. Typical this application Fig. 500-ton metal forming hydraulic press made Farrel-Birmingham, operated placement fluid power pump. Smooth ram movement with sensitive hand lever control enables the operator bring the large crosshead down the work high speed without im- pact, automatically changing slower variable speed for the metal forming operation. variable, pre- set tonnage then held the metal long enough permit flow into its formed alinement. major interest note the trend toward the use hydraulic nisms many machine tools. shows the Rockford Machine Tool Hy-Draulic planer, which the maker says, “Oilgear controlled fluid power for operating the table and cross-feed the outstanding feature our planers and shaper- planers—smooth-flowing power ap- plied straight line close the table-ways, cutting speeds are variable ft. per min. more, table return speeds are independently vari- able 150 ft. per min. more, table reversals are smooth and without shock, and cutting speed attained almost Shaw hydraulic pump motor separate unit combination grinder table Diamond Machine Co. surface grinder. Here the speed the table may varied suit the material and the amount feed re- quired for each pass. reverses automatically, quickly and variable displacement pumps equipped THE IRON AGE, May 1939—47 7 FRANCIS JURASCHEK ° | q ABOVE and cross feeds this RockfordH Draulic planer actuated and cop trolled fluid power drive ° ° ° LEFT fluid power pump ong motor units the table feed Diamond Machine surface grinder. ° ° BELOW 5—Three gear variable placement pumps individual mounted serve three fluid motors (not delivering hp. large printing | | q | | GE, May 1939 ord ner and com rive chine rinder. able hp. press LEFT Vickers complete hydraulic transmission unit comprises within single housing variable displacement and fluid motor. ° ° BELOW 7—American Blower Vulcan-Sinclair variable speed hydraulic coupling 350 hp. capacity driving forced draft fan central station. 4 shade cloth calen- dering machine textile 3 — THE IRON AGE, May 1939—49 mounted one long welded steel base reservoir, and each direct connected individual electric motors. These pumps supply fluid power Oilgear constant motors furnish combined drive 180 hp. large printing press. Fig. there shown the recently developed Vickers complete hydraulic transmission which includes pump and fluid motor the single housing. This particular model equipped for manual adjustment 50—THE IRON AGE, May 1939 the output shaft speed, but other types control are also available. been shown, the pump and the fluid motor any hydrostatic tem may mounted integrally, may separate units located close to- gether widely separated points, has been shown above. When combined one unit mechanism the electric motor which drives