The Iron Age 1928-04-19: Vol 121 Iss 16

THE IRON AGE New York, April 19, 1928 ESTABLISHED 1855 VOL. 121, No. Mass Manufacture Lathes Production Control System, Routing and Mechanical Handling, and Special-Purpose Equipment Reduce Costs Moderate-Sized Plant BURNHAM FINNEY HAT methods mass Monarch Machine Tool Co., Sidney, Ohio, manufac- automobile makers and other large in- turer engine lathes. enumerate the ways and dustrial manufacturers can adapted the means which this company has planned its activi- needs the machine tool builder achieving lower ties along the lines quantity output, however, would operating costs indicated the experience the telling only part the story how production economies and greater shop efficiency have been brought *Resident editor THe Cincinnati abowt, because the system for controlling production, PART NUMBER MOVE CARD Remarks (At Left) “Work Tag,” Which Follows Parts Through Various Operations Until They Reach the Stockroom. are put the time cards the men the sub-assembly department who have worked the order (Upper Right) Time Card, Which Filled Out Workmen and Put Inside the Envelop Known the Work Tag (Lower Right) This Card Made Out Department Foremen When Material Ready Moved Forward for the Next Operation 1067 \ O K AMT. ON OF MT F Ht DEPARTMENT part No- | | EL REMAN = 5108 atl : ZV D Unit No. Amt. on Order Part No, Amt. Finished } 7 the manner which inventories are determined and the process for handling materials are factors the final calculation results. While the layout the ideal far straight-line production concerned, has been arranged that back- finished company’s plant routing work tracking necessary. The stockroom for parts might well called the division line separating shop and the sub-assembly departments from the final assembly department. Parts for Mon- arch engine lathes are made quantities, according orders issued the production department. For example, number gears are put through the shop the result that the expense chang- low the machine one time, with ing set-ups reduced point. Raw Material Needs Estimated Basis Pending Business quirements without lem which has basing its needs upon the done enough raw material hand meet re- surplus prob- accumulating been successfully. amount business the previous upon other data might lead conclusions, the partment reports the management the number outstanding proposals which have been made Monarch dealers. This possible, because each obliged send year or which erroneous sales de- dealer the company copy each inquiry receives and copy his quotations prospective buyers. The management knows from past experi- ence that orders are like- come from certain percentage When this fig- added the which also iat q inquiries number work that ent conception being done, the quantity hich + terial which must Whenever order rece ved by the company = factor order form filled out, copies going department, the production the cost department the bookkeeper, the order department, the stock department, ind the shipping department. Copies are also sent + if t} Lie a ealer and the customer. “Work Tag” Follows Parts Through All Operations When ascertains from its files whether the necessary parts + +h to Lune the production department receives the order, order are stock. not, prepares the part de- part and the name the department which the Attached part. needed, for shows that the first oper- automatic, the Department instruction sheet containing the nan 1 sired, the list which the perations must part sent for the first machining work. upper shaft ring for quick change example, the instruction sheet second operation cleaning and filing from which the casting known Department goes to the 1068—April 19, 1928, The lron Age | SPEED stockroom, When the sent out from the production department they instruction sheet and the drawing are are in- closed envelope called “work the ex- terior the envelop information concerning the name the part, its number, the amount desired, the size, the date issued, the date wanted, the department which the work starts, the date received the stockroom and other pertinent data. The “work tag” follows the parts through their various operations until they reach the stockroom. Upon arrival that point, the tag returned the production department, where filed. “Move Card” Authorizes Transfer Material Next Department When parts are ready sent from one depart- ment another, the foreman fills out red “move card” authorizing the transfer the material the next department listed the instruction sheet. The “move card” given the shifter handling the mate- rial, who turns over the foreman the depart- HENEVER Part Made Blueprints Instruction Sheet and Drawing closed the Tag” Envelop, Which Follows the Work Through All Opera- tions Until Reaches the Stockroom ment which the parts are process delivery. case the assembly certain parts ordered, the production department makes out work tag and sends the stockroom for finished parts. There placed with the parts which are assembled the sub-assembly department accompanies them through the assembling operations and back the finished stockroom. the work tag goes from one operation the next, workmen put small time cards stating the amount time spent that par- After the work tag returns the stock- dispatched the production department, From the time cards contained the production department can and ticular job. room, where filed. work tag envelop the quickly determine the labor cost assembling any part. Each operator the machine shop furnished with cards which registers the time spent every job. The cards each department are collected daily and are sent the production department, which — mec CH MACH! TOOL CO. INSTRUCTION SHEET thereby has accurate record the work done every employee. THe Monarcn Machine Toow Co. As Reverse Plate Hea Gear Box Apron Quadrant 2000 Date Record Kept Cost All Sub- Assemblies The production department keeps record the cost all sub-assemblies, assembly cost card being provided for that purpose. one side the card list the operations through which the work has passed, the time spent the workmen and the rate they received, from which computed the labor cost, the burden and the bur- den cost. the right side the card summary the costs material, labor and burden, the total cost and the cost each sub-assembled part. the back the card detailed the cost all materials going into sub- assemblies. Through the comparatively simple record system just described the pro- duction department able control operations throughout the plant and have detailed information regarding costs, the amount finished parts and sub-assemblies hand and the volume work process the shop. When- ever the time expended specific operation wanted, the department has its files the time cards the men who have worked the job. tion performed new machine Dealer Order No Shipped to Their Order N Entered Promised Ship Via OF List PRICES Disc’ T EXTENSIONS TOTAL MATERIAL COST Raw or Pree Fin Amt] Each Total Price Amount ASSEMBLY COST CARD Our Order No. Their Order No. FACTORY Order Form Made Out Whenever New Business Booked. Copies the filled-out form the bookkeeper and the order, production, stock, cost and shipping departments. The copy shown for the cost department Assembly Date Description From To Material Cost Laber Cost Burden Cost Total Cost Cost Each Cost All Sub-Assemblies Re- corded Assembly Cost Card, Which Filed the Production Depart- ment. the back the card detailed the cost all materials going into sub- assemblies The Iron Age, April 19, 1928—1069 ' ' ! ' Sold to : ' - ' ' ' TIONS List | Countershaft (cone head Large Face Small Face Pl ' Steady Rest : Compound Rest ' Center Sleeve ' ' Chasing Dial ' Chasing Stop Post (complete Compound Wrenct : Tailstock Wrenct Tailstock Lead Screw and Half N ‘ ‘ Chuck Plate Chuck Plate Fitted to ¢ \ ‘ Draw n Atta hme t - ' Oil Pan Pump and Piping Taper Attachment Wiring in Conduit ' ' Motor Type Swit Type ' Chucks Type DEFT ' Part No. or Remarks: Boring Feature the Machine Shop. upper left, boring en holes in a headstock one time ona cial boring machine. up- pe r right, simultaneous boring of 11 holes in a quick-change gear hor in the time it takes to largest hole. upper center, boring three tailstocks at one time re 19, 1928, The Iron Age ICROMETER Col- lars Graduated and Num- bered Parts Are Made with Roll Dies Spe- cial Machines (in Low- Center) Drilling Holes Lathe Beds the Only Ma- chining Operation the Final Assembly The work done radial drill, shown the left background. Flat cars, ft. square, narrow-gage tracks are used support the ends lathe bed when put into po- sition for drilling — > \ Wh ae some other new method, can done without dis- turbing the normal routine the shop. Supervisory Committee and Conferences with Fore- men Are Features Management Formerly was the custom the company have two general superintendents charge the plant, but this arrangement resulted overlapping duties which militated against attaining the greatest efficiency. The management, therefore, divided the re- sponsibility having one the superintendents take charge the machining division and the other the as- sembling division. consider the formulation new shop policies and pass upon all matters major importance relating production there general supervisory consisting the general man- ager, assistant general mana- ger, chief engineer and the two superintendents. Once week each tendent has conference with each foreman under his super- formal way the two discuss the work the men the depart- ment and any other matters pertaining ciency. This plan puts square- the shoulders the indi- vidual foreman his responsibil- ity the management. also gives him voice discussing and deciding issues affecting his department and encourages him developing initiative. Monorail and Lift Trucks Facil- itate Handling Materials Ample provision been made the plant for the me- chanical handling materials. From the receiving shed adjacent the machine shop monorail con- veyor extends through the shop the final as- sembly department. used principally transport lathe beds, and slightly inclined that workman push- ing material suspended from chain has easy task. For transporting small castings within and between various departments Stuebing-Cowan hand-lift trucks are utilized. Practically all castings, whether light heavy, are kept trucks which are stationed along- side the machine operators. the sub-assembly department Louden overhead monorail system parallels the assembly lines, providing adequate means for moving materials. Serving the long bay occupied the final assembly department electric overhead crane operated rope controls from the floor. The runway the crane extends over railroad siding just outside the west end the build- ing and over the truck loading platform, which occu- pies small space the east end. Two workmen, with the aid the crane, crate and load all the lathes shipped the company. For drilling holes the lathe beds, the only ma- chining operation the final assembly department, material handled unusual manner. Small flat cars, about ft. square, have been placed short narrow-gage track extending under and about ft. both sides the drill. Whenever lathe bed put into position for drilling, each the two ends rests one the cars, with the middle part the lathe ready for the drilling operation. save time for workmen, the tool room, situated near the center the shop, has windows all four sides. Each workman has metal checks. Whenever applies for tool, deposits one these checks, which put the rack from which the tool has been taken. Incidentally, the two men charge the tool room not only hand out small tools and jigs the workmen, but also all the graduating the graduating machines and considerable tool and cut- ter grinding. While parts are produced quantities, care exer- cised make sure that the volume manufactured any one time will not clog the stock room and will not a. MPLE Provision for Mechanical Handling Materials Has Been Made the Sub- Assembly Department. overhead mono- rail system suspended lengthwise the as- sembly lines. Hand-lift platforms, which are transported within and between departments lift trucks, are also used. One shown the foreground require inventory out proportion the normal amount business obtained the sales department. fact, the number parts put through shop order depends largely what the most economical set-up run for each part each separate operation. Many parts for small-size lathes are run through lots 200, while some the larger parts are put through lots only 50. Semi-steel lathe beds are rough-planed and rough- milled and are stored for period two months for air-seasoning. Over 1500 are being seasoned all times. After the seasoning process, the beds are fin- ish-planed. All castings are ground, chipped, cleaned and painted air-brush system before machining. Quantity Machining Yields Economies Among the factors which have been responsible large part for reducing costs the time saved va- rious machining operations. Lathe carriages are milled fraction the time formerly required planing, large lots being machined Quantity production clutches attained clutch The Age, April 19, 1928—1071 milling machine which indexes automatically and equipped with power rapid traverse between cuts. Multiple tooling achieved high degree bor- ing processes. Eleven holes are bored quick- change gearbox the time that necessary bore the largest hole, while seven holes are bored head- stock one time special boring machine. Lead screws, rough-chased and seasoned, are finish- chased lathes fitted with precision screws. crometer collars and all other graduated and numbered parts are made with roll dies special machines, and helical gears are cut the hobbing process with ground hobs, roughing and finishing cuts being taken. High-carbon alloy steel gears used Monarch lathes are given the same heat treatment automobile transmission gears, are tested for hardness and are cleaned sand blasting. The final assembly department divided into three units. The first these small unit which small junior lathes are assembled, the second utilized for standard-pattern lathes ranging size from in., while heavy duty lathes, varying size from in., are assembled the third. addition, special unit maintained which lathes intended for single-purpose work are assembled. Each unit manned trained crew specialists. Every as- sembling and alining operation inspected, with 0.001 in. allowed the limit error. Experience has shown, however, that the average error less than half that amount. From the assembly department the finished lathe passes the final painting room where the last coat lacquer enamel sprayed on. The company pre- pared furnish lathes any color which fits into the shop color scheme its customers. Each the factors enumerated has contributed its share the reduction manufacturing costs and increased efficiency production. Considered whole, they have made possible the application this moderate-sized plant the methods usually associated with companies annually turning out thousands units instead 1000, the average number engine lathes manufactured annually the Monarch Ma- chine Tool Co. Overcoming the Tendency Enam- eled Cast Iron Ware Blister Blisters enameled cast iron ware may traced either faulty enamels and process application the castings themselves the conclusion reached the metallurgical and ceramic divisions the United States Bureau Standards. Recently the bureau has been studying the latter type blisters. Differences the blistering tendencies different sets castings were clearly brought out enameling test which in- cluded variety firing treatments. Using this test was found that not only different irons have dif- ferent blistering tendencies, but successive heats the same iron may have different blistering tendencies. The main source blisters from the irons used this work was overcome the removal thin surface layer the castings, through either mechanical chemical means. Traffic Through Sault Ste. Marie Canal Figures the 1927 commerce passing through the canal Sault Ste. Marie have been issued the Corps Engineers the United States Army. The total amount east-bound iron ore given 49,- 963,131 net tons, all which went through the United States canal. Pig iron shipped eastward through the aggregated 78,772 tons, which 57,900 tons came through the American canal and 20,872 tons through the Canadian canal. Copper the amount 67,422 tons came eastward, which 63,963 tons passed through the American canal. West-bound iron ore aggregated 134,937 tons, more than per cent which went through the American canal. Manufactured iron and steel the extent 115,502 tons went westward through the canals, which 82,240 tons traversed the American canal. High-Pressure Steam Plant Described Melvin Engle the Edison Electric Co. Boston was the speaker April before meeting the Providence Engineering Society, Provi- dence, told the first commercial use steam pressure anywhere the world. His de- was the Edgar station the Edison com- pany, which contains, among other things, the largest single-barrel, single-flow, 1800 r.p.m., turbo-generator unit designed for 350 pressure; the largest pressure turbo-generator; the largest boiler feed pumps, measured power required; and the largest under- feed stokers any plant the world. 19, 1928, The Iron Age The speaker traced the great improvements the past two decades the design and operation central station equipment. During this period cast iron has been replaced steel turbine shells; brass bronze steel, monel metal and stainless iron turbine blades; heat-proof insulating material has been devel- oped, and countless changes have been made details and methods manufacture. Coal consumption has been cut virtually half, and the use equipment large capacity has tended hold down the capital charge per unit installed capacity. Improvement Welding Electrodes The Fusion Welding Corporation, which operates the welding equipment and supply division Chicago Steel Wire Co., 103rd Street and Torrence Avenue, Chicago, has completed engineering and research laboratory. Included are well equipped workrooms sup- plied with various forms alternating and direct cur- rent for welding, well oxy-acetylene cutting and welding equipment, and apparatus for testing welds. There also photographic darkroom equipped with the latest type metallographic microscope. The laboratery has also been used for instructing select groups engineers studying some special phases welding. planned establish full working exhibits, not only the engineering laboratory Chicago, but also the company’s offices New York, Cleveland, Kansas City, Mo., and San Francisco. Development work recently completed the neering department has produced two new mild steel welding electrodes, known “blue streak” and “yellow jacket.” “Blue streak” full flux coated electrode and said melt more rapidly than the fastest flow- ing bare wire and, the same time, having excellent stability. especially suited the welding the medium and lighter gage plates and sheets. “Yellow jacket” surfaced electrode, and designed give extreme penetration when with high current heavy material. the laboratory mild steel plates have been successfully welded without beveling the edges rate over ft. per hr. Mechanization coal mines will discussed the April meeting the Ohio section the American Institute Mining and Metallurgical Engineers, held Columbus, April 21. Technical papers will presented during afternoon sessions the chapel Ohio State University. Among the speakers will Wilson, Link-Belt Co., Chicago, who will dis- cuss modern coal cleaning methods. The Jeffrey Mfg. Co., Columbus, will present moving pictures loading and conveying machinery. Registration will the plant the International Derrick Equipment Co. 7 Steels Made Under New Conditions Results German Tests with High-Frequency Induction Furnace— Carbonless, Carbon and Alloy Steels Show Unusual Properties— Future Possibilities* nace installation the Kaiser Wilhelm Insti- tute for Iron Research, Diisseldorf, Germany, during the winter 1925-26 led the conclusion that very strong circulation the metal bath, funda- mental characteristic the ironless induction furnace, would lead new working conditions for the basic chemical reactions producing steel. The following are the results systematic in- vestigation the capabilities the high-frequency furnace for producing steel, which demonstrate the improvement that this new type furnace offers for making alloy steels. Refining Accelerated High-Frequency Furnace Acceleration the speed refining, due the active bath movement, was observed several experi- ments. steel bath, under normal refining slag, was brought from 0.14 per cent carbon 0.03 per cent min. another case, low-carbon stainless steel was produced adding ferrochrome 4.8 per cent carbon and 64.9 per cent chromium carbon-free bath. Directly after the chrome addition, the melt contained 1.04 per cent carbon and 14.5 per cent chromium. After refining period min., the carbon was reduced 0.16 per cent and the chromium 13.42 per cent. strong bath movement also presents some un- desirable factors when melting solid material, due “settlement” that forms the bottom the furnace, which constantly turned over with the continually renewed surface taking oxygen from the furnace atmosphere. For this reason, preferable use fluid charges when using ironless induction furnace for steel work. *Abstract paper Franz Wever and Heinz Neuhauss the Proceedings the Kaiser Wilhelm Institute for Iron Research, Diisseldorf, Germany, Vol. VIII, No. 11. William Adams, one the engineers the Ajax Metal Co., Philadelphia. Silicon and Aluminum Separations Basic Furnace. Silicon and aluminum content fell rapidly 0.80 0.70 0.60 Ps § 0304 1037, The effect deoxidation the strongly circulated bath was investigated additions manganese, silicon and aluminum over-refined heats. The weight the experimental heats was kg. The additions metallic manganese, silicon and aluminum were made after the heat was refined 0.01 0.03 per cent carbon, under lime-fluorspar slag sand slag. The decrease the various constituents was determined continuous sampling, and shown Figs. the basic-lined furnace, the silicon and aluminum content fell very quickly, while the manganese fell more slowly. the other hand, the acid furnace, the manganese and aluminum decreased rapidly, while the reduction silicon was somewhat should especially noted that the content was reduced 0.01 per cent and less without the addition any refining matter. can conclude from the reduction curves that, result the energetic bath move- ment, very rapid reaction obtained between oxygen combined with the iron and the deoxidizing constituents, and, the same time, the resulting deoxidized prod- ucts very rapidly and completely leave the bath and into the slag—with proper slag procedure. The following described experimental heats were made basic furnace lined with magnesite. After melting the charge, two phosphorus slags and finally one sulphur slag were built up. Carbonless Steel Made High-Frequency Furnace direct proof for the conclusions, made from the above washing-out experiments, given heats Nos. 69, and 103 Table These are completely free hot-shortness, although they contain only very small amount manganese and silicon with the very low-carbon content 0.01 per cent. The heats Nos. 69, and 103 were poured directly after the washing-out process without adding any further deoxidizing matter, order prove that this treatment would make them free hot-shortness. Additions ons Additions Manganese Silicon Aluminum Figs. and (Left).—Manganese, Sili- con and Aluminum Separations Acid Furnace. Manganese and aluminum percentage decreased rapidly Manganese Silicon os Aluminum The Iron Age, April 19, 1928—1073 0.70 0.60 0.50 0.30 0.20 0.10 0.10 Bars from these heats, bent dull red heat, were eminently satisfactory. billet from heat No. 103 was rolled into bars measuring 4.5 mm. Some this was also rolled into sheet. Samples this sheet, and 100 mm. widths, were cold rolled, passes, with speed meters per minute without heat treatment be- tween the passes, and brought down 0.2 mm. (90 per cent reduction area). | 1 8 f Carb 8 Steels (I Per ¢ ) H M1 Ss Cu \l 0.17 1 1 0.10 0.01 0.13 0.1 O14 O.O017 0.0 1 0.14 010 01 0.46 0.22 { 0.01 0.49 0.22 6 12.67 1 0.52 0 0.010 12.22 lf 0.43 v 4% 13.42 l 0.44 0.17 0.01 ) 0 13.2 non-rusting chrome iron (rustless iron), contain- ing very little carbon was also produced (Heat No. 99, Table I). This material was tested the firm Sack, after being forged from square section 58-mm. round section. was turned mm. diameter and then made into tube one operation. The tube, which measured 3.5 mm., did not show the smallest defect, inside outside. order verify these good results, heat No. Table the same analysis, was forged and rolled automatic machine. The tube was perfectly smooth nside and outside and free from defects, although cooled below 700 deg. the last operation. ter these excellent results from the carbon-free ferrochrome ingot No. 105, the heat No. 106, Table containing 0.15 per cent carbon, 13.2 per cent chromium and 0.44 per cent manganese, was given rolling test. previously described, this metal had been alloyed with hard ferrochrome and refined from 1.04 per cent its final content. The ingot. after being forged from 90-mm. square section round section and turned mm., was readily rolled matic machine. Carbon Steels Made High-Frequency Furnace Strong circulation the ironless induction furnace has still greater advantages for producing higher car- bon steels, because this case the bath may cleansed any oxygen with carbon, form carbon monoxide gas. The method procedure follows: After re- moving the phosphor slag, pieces carbon are laid the bath, and, the same time, lime-fluorspar- carbon slag covers the bath surface. The bath move- ment then continually brings new metal particles contact with the carbon that any oxide the bath quickly and completely reduced. the beginning this process the bath boils considerably, but becomes very calm with increasing deoxidation. The following complete charging process: Charging Process for Heat Metal charge—40 kg. tube and sheet scrap, and Krupp soft iron. 8.15 meter reading 9418 kwhr 55 o’clock—Charge melted: meter reading 9481 kwhr., lime and fluorspar charged. 10.10 o’clock—100 gm. hammer-scales 10.15 phosphor slag removed; fluorspar charged 10.25 o’clock—100 gm. hammer-scales. 10.35 phosphor slag completely removed 10.36 slag charged. (One part charcoal, weight) (One part fluorspar, weight) (Four parts lime, weight) 10.40 gm. carbon electrode material added bath turbulent 10.56 test: 0.37 per cent 0.18 per cent Mn. Bath less turbulent and hot; 153 gm. electrode material added. 11.06 test: 0.95 per cent Bath very gm. carbon electrode material added. 11.18 test: 1.05 per cent 11.30 gm. electrode material added, ferromanganese inserted. (75 per cent Mn., per cent C). 11.46 poured ladle; gm. and gm. FeSi (93 per cent Si) added. Final analysis: 1.32 per cent 0.25 per cent Mn, 0.12 per cent Si, 0.013 0.011 per cent Table III Summatio 0 Re pe ted Hardening Re sults No. hardenings first High-Fre ql T Ste 61 82 7.39 0.°6 0.013 0.018 0.08 0.02 12 12 13 0.93 116 0.14 0.013 0.024 0.02 0.1¢ 0.01 12 12 12 8 0.93 0.27 0.17 0.020 0.020 Trace 20 20 21 1.07 0.17 0.07 0.017 0.018 18 17 100 1.00 0.28 0.15 1023 0.014 0.06 Trace 18 22 24 1.14 0.13 0.020 0.016 0.02 18 19 0.28 0.27 0.013 0.09 0.01 033 96 1.30 0.18 OO17 0.009 Trace 28 28 29 97 1.32 0.25 0.12 0.012 0.011 Trace 29 31 32 Clay Crucible Stee] 1.11 0.64 0.032 0.10 Trace 17 19 19 1.30 2¢ 7 19 1.019 Trace 0.04 Trace 19 9 20 Graphite Crucible S 0.94 0.010 0.0388 020 0.12 0.018 14 4 15 1.19 4 rO1F 0.040 19 0.12 0.024 SI 23 24 25 78 97 24 14 0.01 039 9 10 10 94 0.014 039 95 25 26 Tab ry Bend S tre th, F cture Evan atio ind Hardness of a Ball Bearing Steel with Various Hardenings Treat Wall Outs Thick Inside Load- Bending Diar Diameter ing, Strength, ness, Rockwell, kg. per sq. mm. Fracture 5/750 780 9.92 1430 183.7 Fine grain struc. 241 24.3 780 9.8 1630 214.8 Fine grain struc 249 23.9 5.98 17.97 1470 191.2 Fine grain struc 27.0 800 9.96 1780 226.0 Very fine 63.2 6.02 9.94 1660 211.8 Very fine 6.02 47.92 1830 233.5 Very fine 63.8 9.95 1150 147.3 Satiny 64.5 9.96 1520 196.5 Satiny 65.1 6.00 1340 172.8 Satiny 65.3 840 3.9 9.9 1290 167.9 Fine grain 66.6 840 3.95 5.97 9.9 1100 143.1 Fine grain 66.4 5.96 9.9 48.02 1040 135.2 Fine grain 67.9 53.93 5.95 9.90 47.98 1040 136.1 Fine grain 67.7 53.95 5.98 47.97 980 127.3 Fine grain 66.9 53.97 6.00 9.96 47.97 1045 134.9 Partly overheated 68.2 53.96 5.98 9.98 1040 134.0 Partly overheated 66.9 3.96 5.97 9.97 1060 136.5 Partly overheated 66.7 19, 1928, The Iron Age Due the tendency the bath movement pull the slag the side walls, was necessary work with comparatively thick slag covering. The tem- perature conditions the small experimental furnace were also unfavorable for maintaining white slag. order that the results may valued correctly, should borne mind that these experiments the bath was always over-refined after being melted down. the heats No. and No. show, the over-refined metal may brought back completely deoxidation using layer carbon under thick lime-fluorspar- carbon slag. spite the small manganese content (0.05 0.06 per cent), both heats were free all hot-shortness. The carbon the two heats was 1.14 and 0.84 per cent respectively, silicon, 0.23 and 0.19 per cent; phosphorus, 0.011 and 0.006 per cent, and sulphur, 0.005 and 0.007 per cent. order arrive some numerical expression for comparing the quality the carbon steels melted with clay crucible, graphite crucible and electric steels, the Maurer repeating hardness test was used. series carbon steels similar analyses were melted outlined the work Maurer and Haufe (E. Maurer and Haufe, und Eisen, Vol. 44, 1926). The test pieces measured mm. square and mm. long. They were notched the middle one side, the notch 1.5 mm. wide and mm. deep and perpen- dicular the long axis. They were then hardened brine the first hardening level 780 deg. order test the sensitiveness the steel against overheating, experiments were made with pieces hard- ened temperatures between 760 and 950 deg. Asa whole, the steels Table III showed very little sensi- Condenser Units with Self-Cleaning Surfaces The Griscom-Russell Co., New York, has developed new surface condenser cooler unit, known the G-R Bentube section. Essentially, each section consists two cast iron headers fixed rigidly proper dis- tances apart angle irons other structural mem- bers. Between these headers are series admiralty metal tubes, somewhat too long for the intervening space. Each tube therefore possesses initially slight bow, deviating from straight line. operation the hot gas liquid cooled en- ters the unit one header, thence through the tubes the other header, and from there other Bentube units series, returned the main circulating system. Hot liquids inside the tubes cause them ex- pand length, and increase the sidewise bow curve. This change curve with changing temperature said sufficient flake off any scale collecting the outside the tubes from the evaporation the cooling water, which may therefore quite hard dirty. tiveness overheating. all pieces fractured, the fine grain lies inside the hardened outer layer. Tests Hard Alloy Steel example for hard alloy steel, chrome ball bearing steel the following analysis was melted: (Heat No. 75) 1.18 per cent C., 0.46 Mn., 0.09 per cent Si., 1.45 per cent Cr., 0.02 per cent P, 0.012 S, 0.072 per cent Os. This was made into tube, 55% mm. Table shows the bending strength, fracture examination and hardness various hardenings. The metallo- graphic examination also showed material free all objections. Similar Results Expected Large Furnaces The foregoing results melting experiments the present time lead the conclusion that the iron- less induction furnace will play important part any further development the electric alloy steels. These results are not attributed working procedure attainable only the laboratory, because believe the main reason for the high excel- lence the high-frequency steel due the funda- mental improvement the physical and chemical con- ditions brought about the bath circulation. These metallurgical fundamentals will remain the same larger furnaces. Therefore, believed pos- sible transfer the results into large operations. The difficulty encountered when working with small fur- naces due the unfavorable relation the working opening the total top surface will greatly im- proved with larger units. Commercial Stocks Industrial Coal Becoming Smaller Estimates the National Association Purchasing Agents place the supply coal various industries days for steel mills, days for by-product coke plants, days for railroads, days for and gas utility plants and days for other industries. The total given 47,388,000 tons March compared with 50,595,000 tons Feb. There has been steady reduction since Oct. when the total was 60,154,000 tons. Industrial consumption during February was placed 36,301,000 tons, drop more than per cent from the January total 37,678,000 tons. With only one more week the coal year yet hear from, estimates the total production the year ended March include 480,000,000 tons bi- tuminous coal, compared with 600,000,000 tons year ago. The figures are based the latest reports from the United States Bureau Mines. anthracite, the coal year will show output about 78,700,000 tons, compared with nearly 92,000,000 tons last year. Cooling Bed for Oil Vapors, Built Sections The Iron Age, April 19, 1928—1075 ‘ — UCCESSFUL the Atlantic from East West the flyers focuses attention the impor- tance alloy steels airplane scribed this article made the framework the famous Lindbergh plane and other planes which have made epoch- making flights the last year. survival any alloy steel the keen compe- tition commercial application depends upon the superior properties which the steel may have for performing any particular service. This particu- larly true when used aircraft construction. Aeronautical engineers are forced conserve weight the very nature the conditions under which the airplane operates. Such conservation can effected using steels with high strength-weight ratio and designing members utilize the material most eco- nomically. The former obtained with heat-treated alloy steels and the latter using shapes with large moment inertia, connected together simple joints. large moment inertia obtained using hollow built-up sections thin material. The most popular form structural member seamless tube. Tubing either circular square cross-section can readily adapted the truss bridge type construction, which almost universally used modern aircraft. carbon steel tube was used the original airplanes and still extensively used the small commercial airplanes. With the increase size the airplane and the higher factors safety demanded the increase horsepower the engines, alloy steel tubing more economical weight and more uniform quality. Three and one-half per cent nickel chromium steels were utilized when the use alloy tubing was confined straight axles with compara- tively low ratio diameter wall thickness. These axles were heated during fabrication develop gen- sile strength 200,000 per sq. in., with minimum elongation per cent, and were entirely satisfactory for the purpose. With the more extended use alloy steel tubing the structure, however, was found desirable develop other alloys which could more economically manufactured very thin gages and large diameters, that is, with large ratio diameter wall thick- ness, and which could welded without great re- duction tensile strength. Steel containing chromium and vanadium the alloying elements could not cold-drawn the ratio desired without excessive waste, but the substitution molybdenum for vana- dium overcame this difficulty. Chrome-molybdenum *Chief of material branch War Department Air Corps, Dayton, Ohio. 1076—April 19, 1928, The Iron Age steel being used the automotive industry for axles, torque tubes and other highly stressed parts, and its adaptation aircraft use was logical development. Fig. 1—Typical Assembly Welded Trusses Chrome-molybdenum tubing manufactured any outside diameter and wall thickness which can economically used aircraft construction. The range sizes extensive for low-carbon tubing. The smallest size ordinarily used in. outside diam- eter 0.028 in. wall thickness. the diameter increases, the ratio diameter wall thickness in- creases, and tubes over in. diameter with wall thickness 0.035 in. are commonly employed. The following analysis called for United States Army specifications and used almost exclusively: Per Cent 0.40-0.60 Per Cent 0.80-1.10 Molybdenum ...... 0.15-0.25 This material has excellent weldability and has air- hardening properties thin sections which are very desirable, since the tensile strength section close the weld not seriously affected. Several tests have been reported different in- vestigators indicating that tensile strength 95,000 Chrome-Molybdenum Steel JOHNSON* Airplane Construction lb. per sq. in. can obtained this material after cooling from the welding heat. The following results obtained plain butt welds were given recent paper prepared for the American Welding Chemical Composition: Per Cent Per Cent 0.28-0.35 Chromium 0.90-1.00 Manganese ....... 0.30-0.60 Molybdenum .. 0.15-0.25 Physical Properties: Unwelded Welded Tensile strength, lb. per sq. in.... 98,000 96,000 75,000 72,000 Yield point, lb. per sq. in......... The above results the tensile test are the average several obtained specimens the range chemical com- position indicated and varying size from in. outside diameter and 0.028 0.093 in. wall thickness unit stress 80,000 lb. per sq. in. for the section close the weld commonly used design order take care any imperfections the weld. The chrome-molybdenum analysis gives excellent response heat treatment. The normalized steel, which material air-cooled from about 1625 deg. Fahr., has ultimate tensile strength and elongation equivalent that obtained quenching oil and tempering 1200 deg. Fahr., but has lower yield point. This air-hardening valuable asset air- craft construction. The welded structures used for the Fuselage Structure the Modern Airplane the body and control surfaces are impractical heat treat quenching account the size the assem- “Welding the Aircraft Structure,” sented fall meet- ing the Detroit, Sept. 20, 1927. Racing Plane with Chrome-Molybdenum Steel Fuselage Reproduced Up- per Left-Hand Cor- ner Opposite Page. The plane the right trans- port airplane with fuselage and land- ing gear the same steel and the slenderness the individual parts, which cause warping and twisting. using normalized quenched and drawn steel with tensile strength 95,000 lb. per sq. in., possible weld these assemblies and retain this strength, due the air- hardening properties analysis. chrome-molybdenum This steel, common with other structural alloy steels, will give wide variation tensile properties, dependent upon the tempering temperature after quenching. Aircraft parts that are quenched must handled carefully prevent damage, account the thin sections and the fairly sharp changes sec- tion due welded seams. Oil quenching generally preferred water quenching. Fig. curve which has been extensively used aircraft manufacturers the basis heat treatment chrome-molybdenum steel. One the most important applications for tubing the fuselage structure. excellent example this type construction shown the fuselage structure (Fig. 1), which represents typical assem- bly welded trusses. All the tubes this assem- bly are chrome-molybdenum steel, heat treated the mill normalizing quenching develop mini- mum tensile strength 95,000 lb. per sq. in., yield point 60,000 lb. per sq. in., and elongation per cent. Fuselages tubing are built for the small airplane weighing 1500 lb. and the larger ones weighing 18,000 type joint commonly used shown Fig. This excellent tension compression joint, and minimum strength 95,000 lb. per sq. in. the pro- jected area the tube practically always attained welders only average ability. Welding can performed means the oxy-acetylene flame elec- tric arc. Welding wire low medium-carbon steel gives excellent results. Closely allied with the use thin tubes for struc- tural members the use sheet steel fittings fasten- ing together various main and sub-assemblies. During the course fabrication, sheet steel fittings are sub- jected severe bending operations and are practically always welded brazed. Material that will fabricate the best when subjected these operations the log- ical material for sheet metal fittings. The different types alloy steels have been thoroughly tested de- termine which give the best results. Knerr, THE IRON AGE Sept. 1921, gave the results number tests 3.5 per cent nickel, nickel-chromium and chrome-vanadium sheet steel, and concluded that the chrome-vanadium was the best type. This was also the conclusion other investigators, and chrome- The Iron Age, April 19, 1928—1077 vanadium has been used quite extensively during the past few years. Recent investigations chrome-molybdenum sheet steel have indicated that this even superior the chrome-vanadium. more easily welded, and bend- ing operations can performed with greater ease. more plastic and does not tend spring back when released from the jig. Normalized material can bent 180 deg. over radius equal the thickness the sheet without cracking. Annealing the material quenching and tempering 1200 1300 deg. Fahr. increases the workability and permits 180-deg. bends over radius equal one-half the thickness in. thickness. has the added advantage that sheets and tubes, welded brazed together, can heat treated unit and properties will developed all parts the as- sembly. Such assembly shown Fig. This fit- Tubing. Heat Fahr., quench heat indicated Carbon, 0.25 to for Thin Sheets Fig. Ex- tensively Used Manufacturers Heat Treatment Chrome- Molybdenum Steel Sheet and Heat to 1600 to 1625 deg malized steel has strength about per sq. in. Chemical analysis: ganese, 0.40 to 0.69; n, 0.80 to 1.10; num, 0.15 to Fig. 5.—Elongation Compared Fig. 2—A Type Welded Joint Commonly are practically identical for the same heat treatment except for the elongation. Since the elongation function the test specimen, the thinner sheets will Basis and re- The nor- tensile 95,000 Ib man- chrom- molybde- ‘ . 0.25 c Values Hardness ‘ Cc / Tempering Tempera- Inn Sheet Stee. | | | | | 0 800 900 1000 1200 emperir nar T Temperature, ting built chrome-molybdenum tubing and not give high value the heavier sheets for the chrome-molybdenum sheets identical analysis, heat treated after welding quenching from 1625 deg. Fahr. oil and tempering 1000 deg. Fahr. de- velop minimum tensile strength 125,000 lb. per The tensile properties the sheets and tubes Fig. Repre- sentative As- mbly of Weld- and Tube Joints 1078—April 19, 1928, The Iron Age same tempering temperature. This indicated the curve shown Fig. When the tests are made tube using the full cross-section for the test specimen, the results are higher than with the standard sheet metal test specimen. The sheet metal specimen used obtaining the results shown the curves similar the new specimen the American Society for Test- ing Materials, with gage length in. and width in. The names the subsidiary companies comprising the Continental Corporation, Kokomo, Ind., will dropped after July These include the Kokomo Steel Wire Co., Kokomo, the Chapman-Price Co., Indian- apolis, and the Superior Sheet Steel Co., Canton, Ohio. Fig. 6—Fish-Mouth Type Weld Used Extensively for Tension and Compression Joints Chrome- Molybdenum Tubing 220 200 | | | 200+ Jens Strength 150 Conception Safety Work Broadens Questions Health Employee Becoming Dominant —Mechanical Safeguards Only Stop-Gap AUEL* HEN accident prevention first began receive systematic attention industry, about years ago, was assumed naturally that was al- most wholly problem guarding tools and equip- ment. was recognized that this would some instances difficult thing do. But was further felt that, this guarding could successfully ac- complished, the problem would solved for all time. After the lapse number years, during which the guarding tools and equipment had gone forward considerable extent, was found that accidents continued. began apparent that accidents happened occasion places other than the point operation, where most accidents had, the absence statistics, been assumed have happened. Many accidents occurred quite remote from the vicinity tools equipment. And today the guarding tools and equipment, though important, may set down only one number major safety precautions. The problem accident prevention, instead being comparatively simple, first believed, commencing recog- nized most complex. Some the other major items involved the work accident prevention are: Minimum labor turnover Good health, involving physical examination, employment and subsequent periods Contentment; absence dissatisfaction and Cleanliness, plant and personal, and neatness Good lighting English language Carefulness safety program can hardly mapped out with any degree completeness without taking all these, and even some others, into consideration. But their relative importance may shift different industries, may shift practically all industries alike, depend- ing varying factors. Some years ago the speaker placed “minimum labor turnover” the greatest safety device that could installed any plant. But, with the growing tend- ency interpret compensation laws more and more liberally and make them more nearly all inclusive, well increase the compensation paid, the item health assumes larger and larger proportions. time, the tendency continued, health will become the greatest phase the accident prevention problem. Good Health Prime Requisite From almost per cent children school have physical defects. They are either excessively above below weight, have defective teeth eye- sight, adenoids seriously enlarged tonsils, etc. Nearly all these defects lend themselves correc- tion taken time. one intelligence would think continuing machine operation for long after was found need repairs, and such repairs would promptly made. But our most valuable machines all, our young folks, either not inspect else inspect haphazard manner. And largely fail make repairs, but are inclined hope they may with time outgrow the need repairs. *Manager employees’ service department Westinghouse Electric Mfg. Co.. East Pittsburgh. This abstract address before the recent Pennsylvania State Safety Con- held Philadelphia. Physicians employed the industries were origi- nally used largely administer em- ployees who became sick, well take care any who might meet with accident. This work was undertaken principally for Naturally, however, turn led occasional physi- cal examination employees. due course, came recognized that there were economic advantages physical examination and that could profitably extended applicants for employment, and made apply all employees periodic intervals. Physical Examination Beneficial Regardless the causes which brought about physi- cal examination, here stay and developed and extended beyond the industries. Its effect will greatly beneficial, and more and more far-reaching, with the passing the years. The industries want see every worker who ap- plies for job obtain the one best suited him. Where physical examination shows individual lack- ing certain respects, industry will, the main, still endeavor place him. Our company will hire worker with defective eyesight, continue one our employ, will procure corrective glasses. case defective teeth hernia may engage him will, within specified time, have the defect corrected. Investigation many years ago, the causes accident, developed the supposed fact that about per cent were due carelessness. seeking remedy for this found that carelessness was many cases produced something else—that might itself effect and not cause. Possible causes carelessness include largely worry and ill health. Good Vision Corollary Proper Lighting Many accidents have been traced poor eyesight, corollary ill health. Admitting this, but step further say that many accidents have been due poor lighting, producing the equivalent poor vision. Some years ago the Travelers’ Co. prepared chart 95,000 accidents. This showed increase the short, dark days winter and decrease the long, light days summer. This has been confirmed other investigators. Illuminating engineers have the past been much blame for not impressing upon factory managers the value good lighting and its comparative cheap- ness. Reference early tables lighting intensities for various kinds work will generally show that, while they recommended anywhere from foot- candles for drafting rooms, yet from foot- candles were deemed liberal for manufacturing. They seemed overlook entirely the fact that many times the worker and the inspector had make measurements close 0.001 in., reading the fine lines verniers and micrometers. And they must obtain the figures from soiled, crumpled and more less illegible blue prints. have found cases defective eyesight—one particular, with per cent vision one eye and per cent the other—yet the employee did not even know there was anything the matter. Much this can traced the diseases childhood. The Iron Age, April 19, | Ford Shop Changes Estimated tensively Employed FAY LEONE FAUROTE* those production men interested the fabrica- car demanded slower pace first order that the tion metals, especially steel, the new Model inspection requirements might carefully learned. Ford furnishes striking example what can Not only the parts but many the machines and done electr