The Iron Age 1938-11-24: Vol 142 Iss 21

FRITZ FRANK President VAN DEVENTER Editor Managing Editor News Editor Machinery Editor Art Bditor Metallurgical Bdibor FINDLEY Editor Emeritus Associate Editors JURASCHEK Consulting Editor Washington Editor Resident District Editors Pittsburgh Chicago Cleveland Detroit Editorial Correspondents London, England Cincinnati FRAZAR Boston Hamburg, Germany MEYER Milwaukee SANDERSON CHARLES Post San Francisco ASA Toronto, Ontario Birmingham LEROY ALLISON Roy EDMONDs : Newark, N. J. St. Louis TURNER, JR. Buffalo Owned and Published CHILTON COMPANY (Incorporated) Editorial and Executive Offices 239 West 39th St., New York, Publication Office Chestnut and 56th Sts., Philadelphia, Pa. OFFICERS AND DIRECTORS Cc. A. MUSSELMAN, President FRITZ FRANK, Executive Vice-President FREDERIC STEVENS, Vice-President JOSEPH HILDRETH, Vice-President GEORGE H. GRIFFITHS, Vice-President EVERIT B. TEROUNE, Vice-President WILLIAM BARBER, Treasurer JOHN BLAIR Secretary JOHN VAN DEVENTER, JULIAN CHASE, THOMAS KANR, CHARLES BAUR, CARROLL BUZBY, FAHRENDORF BAUR, General Advertising Manager DIX, Manager Reader Service Member, Audit Bureau of Circulations Member Associated Business Papers Indexed in the Industrial Arts Index. Published every Thursday. Subscrip- tion Price: United States and Pos- Mexico, Cuba, $6.00; Can- ada, $8.50; Foreign, $12.00 year. Single copy, cents. Cable Address, **Ironage, N. ADVERTISING STAFF Emerson Findley, 621 Union Bldg., Cleveland B. L. Herman, Chilton Bldg., Chestnut & 56th Sts., Philadelphia, Pa. Hottenstein, 802 Otis Chicago Leonard, 239 39th St., New York Peirce Lewis. 7310 Woodward Ave., Detroit Ober, 239 39th St., New York W. B. Robinson, 428 Park Bidg., Pittsburgh D. C. Warren, P. O. Box 81, Hartford, Conn. RON Contents NOVEMBER 24, 1938 Arnold's Pain Latest Patent Medicine Types Common Nuts and Their Selection Ingots Flame-Cut Blooming Mill Size General Motors Opens Ternstedt Trenton Division Applying Electric-Furnace Brazing Metals Sprayed Zinc for Protection Against Corrosion . New Unit Heaters and Other Plant Service Apparatus 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 1938 by Chilton Company (Inc.) 114 2 a GUESSWO OUT STEEL TREATING Special Alloy Steel Service Helps User Quickly Secure Desired Results Ryerson certifies the known uniform high quality all steels stock—from the thinnest sheet the heaviest plate—from the smallest bar the largest beam. addition. have developed special alloy steel service that big help securing desired heat treatment re- sults. Whole heats ideal close range analysis are selected for each number; special data sheets showing chemical and physical prop- Principal products stock for Imme- diate Shipment include—Bars, Struc- turals, Shafting, Plates, Alloy Steel, Tool Steel, Spring Steel, Iron and Steel Sheets, Stainless, Babbitt, Strip Steel, Welding Rod, Tubing, etc. erties, grain size, cleanliness rating and actual results heat treatment tests, are sent with every shipment Ryerson Certified Alloy Steels. testing unnecessary. The heat treater knows the characteristics the steel. This complete information makes does not take chances and gets better results less time. tell Write for booklet R2. There are many other advantages. you the complete story. Joseph Ryerson Son, Inc. Plants at: Milwaukee, St. Louis, Cincinnati, Detroit, Buffalo, Boston, Philadelphia, Jersey | ESTABLISHED Arnold’s THE IRON AGE ... NOVEMBER 24, Vol. 142, No. Pain Killer—the Latest Patent Medicine which apparently can lead Government control industry's advertising budgets. least that the impression one likely obtain from study Mr. Arnold's order forbidding Ford Motor Co. and Chrysler Corp. advertise specific finance companies. ATTORNEY GENERAL THURMAN ARNOLD has just taken step All publications have obvious and perhaps selfish interest what Mr. Arnold proposes. Industry, believe, will have similar interest when the implications the Assis- tant Attorney General's order are fully understood. said Mr. Arnold, fostered when advertising used put com- petitors disadvantage for the sole reason that they not have resources suffi- expend equally large sums advertising particular products the services This means, apparently, that the large company with financial resources adver- tise broad scale, the small company which finds profitable spend larger share its money for advertising than its competitors spend, going run into trouble Washington. But how about the company which invests relatively larger share its money new machinery, new tools? going penalized because purchases new machinery and resulting better products have brought more business than its com- petitors? How about industrial research? that curbed through New Deal fears that such research may bring monopoly? And how about the company which gets more business because its high standard labor relations cuts its costs? Frankly, don't know whether the time will come when purchasing agent will need from some Government official before signing order for new lathe. However, Mr. Arnold's move control advertising budgets clearly another link the iron ring control with which the New Deal faction continues, despite the re- cent election results, encircle free enterprise and the American way doing business. + A 4 ey ~ | : + 4 . Types Common Nuts and rapid growth machinery and machine made products has brought with enormously increased variety small parts. The bolt and nut industry has had large share the increase new styles and types common parts. The nut in- dustry now produces great variety products that the selection the best possible combination strength, accuracy, value and reliabil- ity has become somewhat prob- lem. While true that the Ameri- can Institute Bolt, Nut Rivet Manufacturers has taken the most commonly used nuts and set stand- ards for them, that are followed most the nut manufacturers, yet even these relatively few types pre- sent more less complex picture. The man who uses the nuts undoubt- edly knows what wants, but often does not know what can obtained regular standard stock item. specifying the same type nut for every job may lose the advantages some other types nuts. may design nut fit his own needs, and have manufactured special, but usually there some standard nut that will serve his purpose more econom- ically. Most the pertinent facts concern- ing the standards and manufacture the common nut have been gathered and presented below. necessity has been made brief, and some items relatively less importance have been omitted. The terms used with reference nut dimensions illustrated Fig. are explained below. Tapped Hole The tapped hole the most impor- tant element nut, all dimen- sions are based its diameter. The tapped hole usually threaded with either coarse fine thread, sections which are shown Fig. The threads shown Fig. are drawn the same scale show the relative Metallurgical Engineer—Lamson essions Co.—Cleveland. Technical Assistant Vice-Presi- dent—Lamson Sessions Co. 20—THE IRON AGE, November 24, 1938 proportions each type thread. The coarse thread, formerly the USS thread, now known the American Standard coarse thread. deeper and has fewer threads the inch than the American Standard fine thread for- merly known the SAE thread. There are several other types screw threads, but they are not commonly used, and will not discussed here. Across Flats The width across flats nut governs the thickness the wall metal between the hole and the out- side surface, the size the wrench used, and the amount bearing surface the nut. B—Width Across Corners The width across corners dimension dependent upon the width across flats, and serves limit the rounding the corners the nut. H—Thickness The thickness the nut the fac- tor which largely determines its strip- @---------- ABOVE All dimensions are based the diameter the tapped hole, the most im- portant element nut. ping strength, all other things being equal, such type thread, material, thread fit, workmanship, etc. C—Bearing Surface The surface the nut that comes contact with the work called the bearing surface. Washer Face The washer face small raised washer-like surface formed the bearing surface semi-finished and finished nuts. diameter approximately equal the width across flats, and has mini- mum thickness 1/64 in. The pur- pose the washer face present smooth finished surface the work and insure its being perpendicular the axis the tapped hole. A—Chamfer chamfered, that is, the corners are formed angle, usually about deg. semi-finished nut may have all corners both sides chamfered, BELOW IG. 2—The coarse thread, known the American Standard coarse thread, deeper and has fewer threads the inch than the fine thread. Coarse Thread Fine Thread 7 e ‘ Their Selection either flat surface acting bearing surface, instead washer face ma- chined the bottom. This type nut known double chamfered nut, and may assembled from either side. Nuts may divided into four clas- sifications regular, heavy, light, machine screw and stove bolt, according their dimensional proportions. II—Unfinished, semi-finished and full finished, according the degree finish. pressed, cold punched, cold forged and milled from bar, according the method manufacture. IV—Full, jam, slotted nuts, according styles. The standards set the Ameri- can Institute Bolt, Nut Rivet Manufacturers have three basic classes —American Standard regular, Ameri- can Standard heavy, and American Standard light. Fig. shows the rela- tive size each type nut. The light nut smaller across flats than the regular nut, but with the exception the semi-finished regular nut, has the same thickness. The American Stand- ard regular and heavy semi-finished nuts are 1/64 in. 3/64 in. thinner than the unfinished and finished nuts. This variation was made allow for machining unfinished nuts the semi- finished class. The American Standard “heavy” nut both wider across flats and thicker than the American Standard nut. Both the regular and heavy nuts are usually tapped the American Standard The American Standard “light” nut tapped the American Standard fine thread. The standards for machine screw and stove bolt nuts cover both the plain square nut and the chamfered hexagon nut. The square nut usual- furnished with stove bolts. How- ever, hexagon stove bolt nuts and square machine screw nuts are not un- common. Both types are made cold punching. Light Regular Heavy LEFT AND ABOVE the various types nuts. Note the light nut smaller across flats than the regular nut, but with the exception the semi-finished regular nut, has the same thickness. ° HACKSTEDDE* American Institute Bolt, Nut and Rivet Manufacturers ° ° ° Fig. shows the different types finish that nuts may have. The most commonly used nut the unfinished. tapped, but has further ma- chining finishing any its sur- faces. This type made either hot pressed cold punched, and may made hexagon square. The semi- finished nut tapped, and has either washer face formed the bearing surface, double chamfered with either side acting the bearing sur- face. Semi-finished nuts are made milling from the bar, cold forging, cold punching. Full finished nuts are used comparatively small quantities today and are usually made the customer’s specifications. The finish and strength nut affected considerable extent the method manufacture. For in- stance, the hot pressed nut dis- tinguished the black oxide coating film with which covered. has rough sides and somewhat round- corners. This type made punching nut blanks from hot rolled low medium carbon steel bars BELOW 4—Types finishes. Square Hex Washer Face Double Chamfered Washer Face FINISHED THE IRON AGE, November 24, Regular Fic. 5—Steps the cold forging process, which consists upsetting the hexagon nut blank from round wire. forging temperature. The nut blanks. are cooled before burring and tapping different machines. The slow cool- ing the metal air from the high temperature forms oxide scale the surface, well serving annealing process which material comparatively soft state. black oxide scale, which covers its entire surface, except threads, acts slight extent inhibitor mild corrosion. The hot pressed nut limited uses where rough unfinished surfaces are held together, and extreme accuracy not necessity. necessary, nut greater strength can made using steel higher carbon content. The cold punched nut, the other hand, has bright finish. The edges and corners are sharper, and fairly accurate nut capable being held closer tolerances than the hot 7—A set American Standard light nuts arranged order and showing the difference sions. 22—THE AGE, November 24, 1938 pressed nut. The cold punched nut punched and trimmed from bar low carbon steel. the case the hot pressed nut, the cold punched nut tapped separate machine. The cold punched nut can faced the bearing surface, and ished that the class the semi-finished nut, although ordinarily IG. 6—Cross sec- tion cold forged nut, etched show the flow lines. the cold punched, well the hot pressed, sold unfinished nut. bar nut distinguished from the hot pressed and cold punched types smooth sides, sharp edges, and shiny milling, usually from low carbon bar stock, but can made from almost any machinable material available The bar nut can held closer tolerances than either the hot pressed cold punched types, and finished nut. commonly used with machined finished surfaces, and similar applications where its accurate dimensions and smooth pearance make valuable. The cold forged nut the result the latest development nut man- ufacture. combines the accuracy and smooth finish the semi-finished bar nut with the toughness the cold punched nut. The cold forged nut usually made with double chamfer, and with both ends the tapped hole countersunk, These features the ease and speed assembly. The cold forging process consists up- setting the hexagon nut blank from round wire several steps shown automatic tapping machine, make semi-finished nut. The steel used manufacturing the nut hardened considerable extent the cold working necessary produce the hexagon shape from round wire. addition the cold working which adds the hardness and strength the nut, the forging the metal ar- ranges the flow lines the crystal structure such manner op- pose the forces that normally tend split the nut. Fig. shows cross sec- tion cold forged nut etched show the flow lines. feature this process that was first source annoyance the manufacturer, has proven benefit the custom- er. The severe upsetting the wire causes even the very small seams and cracks open up, easily visible the the nuts are all carefully in- “= & 4 4 a AMERICAN STANDARD AMERICAN STANDARD STOVE BOLT MACHINE SCREW NUTS SQUARE HEXAGON AMERICAN STANDARD REGULAR HEAVY Hex. Square Hex. Hex. Hex. Square Hex. Unfinished Semi-Finished Finished Unfinished Semi-Finished Jam (Hex.) Jam Jam Jam (Hex.) Jam Reg Reg Reg Heavy Heavy Slotted Slotted AMERICAN STANDARD LIGHT Hex. Hex. Finished Semi-Finished Jam Jam Heavy Light Slotted Thick Thick Slotted Castle spected the buyer insured mate- rial free from defects. The process has been developed such extent that non-ferrous alloys, well plain carbon steels, have been successfully cold forged into nuts. Cold forged nuts can made almost any material that can cold upset. general standards, finishes and types manufacture that have been discussed cover great many different sizes and styles nuts. The follow- ing table lists the various standards and the types nuts which they cover. will noted that the Amer- ican Standard light nut usually made semi-finished hexagon, and that addition jam, light and slotted nuts, made the thick nut, thick slotted nut and castle nut. Fig. shows set American Standard light nuts arranged the order named above show the difference dimen- sions. American Standard regular and heavy nuts are made finished, semi- finished and unfinished. Square nuts are made only unfinished and are not available the jam slotted styles. The subject nut standards and manufacture more complex than has been pictured above. However, the general facts concerning common nuts have been covered and may prove assistance the person who uses buys such products. Ingots Flame-Cut Blooming Mill Size flame cutting splitting per cent nickel ingots into sizes suitable for rolling tion. The plant which this was done had rush order for strips the same analysis, but the ingots, which had been their yards for several years, were too large handled the bloomer the 72-in. strip mill. They weighed tons each, and ranged size from 20-in. 60-in. 5-ft. 24-in. 68-in. 7-ft. The ingots had accumulated crust dirt and several them had developed large cracks. addition they contained blowholes steel ingot being cut bloom- ing mill size means portable oxy-acetylene cutting machine. When be- cause dirt and blowholes, the cut became lost, oxygen lance was brought into play. (Photo courtesy Linde Air Products Co.) 4 A Although much the scaly sur- face possible was removed before cutting, the generally poor condition made necessary somewhat special- ized cutting procedure. The equip- ment consisted heavy-duty port- able cutting machine mounted with special heavy-duty, water-cooled blow- pipe. Oxygen cylinders were mani- folded, and the acetylene supply was obtained from stationary generator. The cutting machine was set travel and the oxygen pressure was main- tained between per sq. in. the start the cutting was found that dirt and blowholes were sufficient cause the cut lost after had progressed only few inches. This difficulty was overcome, and continuous cutting action main- tained, use oxygen lance rigged out in. diameter pipe. Each time appeared that the drag the cut was getting too great and that the cut might lost, the lance was brought into play. mentary oxygen gage mounted the inlet the blowpipe means adaptor provided the operator with exact reading the oxygen pressure right the blowpipe. THE IRON AGE, November 24, ABOVE VARIETY roll forming ma- chines special design are used produce from coiled strip stock the large number formed sections developed for the Fisher Unisteel turret top body. This photograph shows such set forming rolls making U-shaped roof bow members. The unit the left continuous roll seam welder, followed cut- off machine. RIGHT sections formed from strip stock roll forming machines are literally wrapped around rotating, horizontal bending fixture form garnish moldings for window frames for Fisher bodies. J ABOVE FRONT view the Ternstedt Trenton Division plant Gen- eral Motors. The new 20-acre fac- tory, which being operated under the jurisdiction the Fisher Body division, produces body hardware and fittings for shipment assembly plants the East and South. RIGHT OOD graining effects being produced garnish molding with the aid gelatin duced proprietary process. The two graining rooms are air- conditioned. Prior graining, the moldings have been degreased ground coat and baked for min. operation the new Ternstedt Trenton (N. J.) Division Gen- eral Motors Corp. completely mech- anized through the use monorail conveyors, conveyor belts, elevators chute-feed bins. Wherever possible, the material handling equipment de- signed deliver the work the cor- rect table level eliminate bending reaching the part the operator. The plant, which has re- cently been completed, will oper- ated unit Fisher Body. every handling Another provision the interests the worker the establishment RIGHT the pattern placed garnish molding the grain- shading spray coat applied certain portions the frame, fol- lowed 20-min. bake. This spraying done the water-wash spray booths shown, supplied with filtered air and eliminating the necessity for face masks. chem- ical added the wash water dissolve all lacquer particles be- fore air from the booths ex- hausted into the atmosphere. banks materials strategic points prevent the layoff operators further along the production cycle the event equipment failure. addition, month’s supply raw ma- terials will kept hand all times 920-ft. storage crane- way, including 2500 tons strip steel, 900,000 Ib. zinc, 36,000 Ib. alumi- num and 27,000 copper. There are also large storage hoppers between many the individual machines. will also possible store 18% days’ production body hardware the warehouse, that Ternstedt can continue supply Fisher Body and General Motors plants unfore- seen plant shutdown This storage system will also permit the rotation parts manufacture the different progressive work lines. The operations carried this plant, like the main Ternstedt plant Detroit, consist primarily metal forming and stamping, metal finishing, die casting, polishing and plating. the Trenton plant, die casting ma- chines have been installed, them take care the larger items. Four large melting furnaces fired pro- pane gas supply the zinc-base alloys RIGHT the 120-ft. long automatic bright nickel plating machine where the work, such the door han- dles shown the racks, are lifted out one tank and transferred another auto- matically. All plating solu- tions are controlled central laboratory. automo- bile door handles are polished this special automatic buffing machine, ft. length and equipped with heads disposed various angles take every part the work piece. Following operations, the han- are transported monorail automatic solvent degreaser prior plating. the machine, handled ladles overhead monorail. the same department are machines and automatic nickel and chromium plating machines. There another large automatic nickel plating machine the division devoted the manufacture control ventilating parts and assemblies. Here also have been polishing machines, and battery small parts. Roll forming machines and special bending apparatus convert the strip steel into the desired shape. Similar equipment used the gar- nish molding department, except that the finishing process, that graining (illustrated), different. this tion, besides five separate forming roll lines for strip stock, there battery 133 presses ranging 180-ton capacity. Overhead monorails weave through this section, including one = door handles are pro- duced group four die casting machines, supplied with monorail conveyor. After being cast, the handles the trim- mers, then battery ma- chines where the steel inserts are machined. Handling performed monorails, but there are also two belt conveyors serving the die casting department. ASTE material from plat- ing solutions ized these tanks before be- ing discharged into sewers. Daily waste passed through one these 18x tanks the rate 150,000 gal. per hr., the chemical neutralization treatment taking about hr. Treatment the week-end waste done the other 000-gal. tank much slower rate. Occasional large dump- ings nickel and copper cyan- ides are neutralized glass- lined tank 13,500- gal. capacity over period, and both the nickel and copper are recovered. The cyanogen gas produced the process diluted with 5000 air supplied two fans and exhausted through stack. line that contacts every inspection sta tion and carries rejected pieces central salvage station. The paint finishing section sepa- serviced means unified system wash booths supplied with filtered air, and paint supplied from storage and mixing room. Graining done two separate air-conditioned rooms, the mechanical hardware depart ment, there battery spot and projection welding machines, sizable group presses. Many plating body fittings performed this automatic machine, ft. length. The cam controlled arms raise and lower the racks out and into the various baths. This plating unit cen- trally located and served monorails coming from the nickel-plating inspection tions. After chromium plating, decorative striping applied hand. unexposed parts made this depart- ment are finished black enamel installation, over 100 ft. long. Other arts through bonderizing treat ment combined with ground coating. The bonderizing units are the spray Deck component, door and mote control locks are produced another section this department. manufacture all parts where welds are required; others are plated after fabrication matic barrel type plater, which the work carried through the various solutions while being rotated her-lined baskets. The outside door hinge ing section interesting view the fact that elevators bucket con- veyors, some which horizontal and vertical movement, are convey the parts from one machine the next. This method material handling used because the weight the parts, such hinge straps made out 9/32 in. cold rolled other feature the use large di- vided storage hoppers for separating male and female blanks and holding hanks semi-finished parts while tools are being changed such ma- chines broaches. THE IRON AGE, November 24, 1938—27 Electric-Furnace VARIETY forms brazing metal can used, such wire, foil, slugs, electroplate, molten spray and paste. Some these forms are pictured Fig. 53. The choice depends upon number factors which are related the size and shape the product, accessibility for apply- ing the brazing metal, quantity brazing metal required, desired ap- pearance the brazed product, and last but not least, cost. The following discussion based general the use copper the brazing metal. Although holds most cases for lower-melting alloys well, there are exceptions. The loca- tion the brazing metal, the form, and the amount, have great deal with the success the job, and for that reason the subject apply- ing the brazing metal deserves con- sideration. Wire Convenient Use common form which brazing metal applied that wire rings. Many assemblies cylindrical members, over which rings fit nicely. addition, the rings provide medium for supplying the same amount brazing metal every assembly, and the cost the rings and the cost applying them quite low. The rings can formed hand, necessary, but most companies make them automatic machines wind the wire mandrels and then cut through the helices thus formed with shears nippers. Some companies form rings ring coilers made Sleeper Hartley, Inc., Worcester, Mass. These ma- chines make from 200 rings per min., depending upon the sizes rings and machines, and feed them long shafts which are used for trans- porting and storing the rings that they not become locked into each other. After starting the machine, the operator free other work until shaft filled. Brazing Tubes Tube Sheets,” Leo Edelson, Handy Harman, The Welding Journal, February, 1938, Page 32, Vol. 28—THE IRON AGE, November 24, 1938 ECAUSE its basic impor- tance, the subject loca- tion, form and amount braz- ing metal for various types furnace-brazed jobs dealt with length Mr. Webber this sixth article his series. The discussion deals for the most part with copper the brazing metal. The illustrations are drawn from successful prac- tice various fields. Another company successfully em- ploys simple manual-winding outfit consisting crank, some gears, and chuck, with assortment about mandrels, any one which can put into the chuck form helices the desired size. While the crank turned with the right hand, the wire fed the mandrel with the left. The various assemblies which come through the brazing department are carefully card-indexed, with the sizes the wire rings indicated the cards mandrel numbers and wire gages. ordinary commercial grade copper wire generally employed for electric-furnace brazing. Annealed wire commonly used because easily formed, but, some cases, hard wire more desirable. springiness needed hold the wire position, the rings should made hard half-hard wire. Hints Placing Wire Rings The sketches shown Fig. give few practical hints putting the rings place. When pressing cop- per-wire ring down over cylindrical member, the ring commonly pushed clear down against the shoulder. some products, how- ever, found that the brazing tends flow out the shoulder in- stead flowing down into the joint. For this problem effective remedy leave the ring slightly above the joint indicated. The ring must formed slightly undersize, course, order hug the tube. Then, when melts, the brazing metal will flow down the wall the tube and enter the joint before can get across the horizontal shoulder. brazing metal starts into the joint, attraction, this scheme can gen- erally counted upon give posi- tive results. When the cylindrical member has horizontal axis, shown Fig. 54, quite important place the cop- per ring snugly against the shoulder that can drawn into the joint from the shoulder, may run down around the walls the tube before has chance creep over the joint. For the same reason, important that the shoulder make square corner with the tube and not rounded chamfered. When spuds are pressed into the walls hollow receptacles, there are sometimes reasons for putting them the outside the inside, shown and they are placed the projecting ends the outside. tening the cylinder wall generally takes place during the swaging, which desirable order provide good contact throughout the joint. Obvi- ously impossible apply cop- per ring the outside, but copper ring can snapped over and locked into groove made the chamfered corner the spud which butts against the cylinder wall, shown When attached this rings can depended upon stay place, even though they are out sight inside the assembly. When the copper melts, will flow the out- side showing that the joint brazed, assuming that the shell properly vented will discussed later. the spud should project inward from the outside the shell, shown = | | sd | | | | | 4 | | | chamfer the corner the shoulder because easy see whether the rings are place next the joints when the assemblies are set the furnace conveyor charging trays. Rings Embedded Grooves frequently desirable embed the rings grooves within the joints, Available forms brazing metal include powder; helices wound man- drel, subsequently cut shears; bands; wire coils and straight lengths; rings; and foil various forms, shown right. shown Fig. 55. For example, the valve body refrigerator float chamber shown and also shown photographically Fig. [Iron Sept. 15, page 32] best prepared for furnace brazing this manner. Formerly, copper-wire ring was placed around the outside the shoulder next the joint. This ar- rangement gave good braze but the copper crept into the threads, re- quiring that they sometimes cleaned out, and also flowed down the sides the float chamber and sometimes Metals had ground off the bottom where weld was subsequently made. cutting down the amount cop- per, which ordinarily solves such dif- ficulties, was found that insufficient brazing metal was available supply the joint after the copper ran over the surfaces the shell. However, putting the ring inside the groove illustrated, only sufficient copper supplied braze the joint, and the troubles described have been com- pletely eliminated. The assemblies are now furnace brazed with neat fil- lets the inside and outside extremi- ties the joints, and with the sur- rounding surfaces completely free from copper. The view Fig. 55, shows cop- per-wire ring groove where desired make sure that will properly located. When parts are being turned screw machines ° ° WEBBER Industrial Department, General Electric Co., Schenectady, simple matter add groove for the brazing metal. Rings Held Place Shoulder Fig. gives another suggestion the use wire rings, indicating the hold the ring place. shows tube projecting above collar, serve this purpose, while shows the collar projecting over the end the tube. either case the wire ring will keep its position while the assembly being handled around the shop and carried through the furnace, and the corner will serve reservoir for the mol- ten brazing metal. the other hand, obviously difficult positively locate when the surfaces are flush, shown the assembly must have flush surfaces, would best try put the copper groove the tube. THE IRON AGE, November 24, 1938—29 ‘ * 4 j jc F x, | | Wire close Wire ring joint elevated outside, Wire groove inside Spud hell ABOVE Different methods attaching wire rings parts preparatory furnace brazing: vertical axis, ring above joint; horizontal axis, ring close joint; inside spud, wire groove inside; and outside spud, wire outside against shell. RIGHT 1G. 56—Provision should made fix the location the rings, and provide reservoir for the brazing metal and compromise would chamfer the end the tube and countersink the hole provide trough which the copper ring could lie while pass- ing through the furnace. Edelson* has shown good way provide reservoir for silver-braz- ing alloys when brazing tubes tube sheets, counterboring the holes receive bands the brazing alloy Fig. 56. This ingenious scheme works quite effectively. sometimes desirable neces- sary tie the ends copper-wire rings order hold the wire place. This frequently when the diameter the parts rather large, say in. more, because the rings then become large that they might not stay well place unless tied. Straight Wire for Straight Seams Wires straight lengths are some- times used for brazing straight seams. The butt-jointed tube shown Fig. 57, for example, would furnace brazed this manner. desirable have the joint the bottom, when passing through the furnace, that the copper can puddle into it. Butt joints such this are difficult fur- nace braze successfully because their tendency open the heat. 30—THE IRON AGE, November 24, 1938 Avoid this well avoid vertical such shown 58, possible, seaills because the copper flows downward due the force gravity, and may not braze the joint. straight wires are used inside tubular members they any length desired. But used the outside assemblies, best limit their length to, say, in., possible, and use several pieces end- to-end necessary. Long wires some- times twist and warp the heat and Provide shoulders possible hold Copper rings Stake prevent slipping Flush Tub Tube Band silver- brazing counterbored hole Also difficult keep them straight handling them around the ‘shop. Some companies which automatically straighten and cut wire into desired lengths relatively high speed. The Artos Engineering Co., Milwaukee, makes machine com- monly employed for this purpose. Foil Sometimes Used Brazing Metal metal the form foil, cut from sheets strip, another convenient form for certain jobs. this form easy apply, gives good uniformity, and economical. good example where foil has been used advantage the prepa- ration the float shown Fig. 59. copper-wire ring was tied around the middle where shells join and small amount cop- per-powder paste was daubed the bracket the top assure the filling any pores developed the projec- tion welding the bracket the shell. experimenting was found that piece copper foil, 0.010 in. thick in. square, would give equally good results with considerable savings the cost preparation. Now, when the foil copper not only forms nice fillet around the bracket and fills any pores the welds, but also runs down over the upper shell into the joint and forms neat fillet entirely around the middle seam, giv- ing uniformly-tight product with negligible rejections for success this scheme partly due steel which the shells are made, which the copper readily instead adhering. The former operations tying the ring and daubing the paste were performed separate operators, while now the pieces copper foil are put the assemblies the fur- nace operator after the floats are set nace Foil Put Inside Joints foil can put inside joints. illustrates use foil-copper washer for brazing refrigerator cranks. When the copper melts, creeps throughout the entire joint. Copper can seen the end the tenon looking into the hole the indication that the joint brazed. sometimes used between two members, shown which case 55—Wire rings can embedded within the joints grooves shown here. Copper wire Butt joint Have joint and copper bottom When straight seams are encountered, brazing metal can applied the form straight wire, placed above the possible. Short lengths wire are sometimes used outside seams avoid warp- age long pieces. 7 | ° ° | Wi re that the upper member can settle down after the brazing metal melts, order provide intimate contact be- tween the surfaces brazed and fill any voids which might form. For the same reasons necessary that the abutting surfaces square refrigerator crank prepared with cop per foil shown section Fig. 60, illustrates assembly with piece foil between the members furnace brazed, carrying out the idea furnace brazed the Queen City Steel Treating Co., Cincinnati, for the White Mfg. Co., Morton, was formerly brass casting, but was bracket assembly wreath holders. Now that fur- nace brazed has greater strength and lower cost than the casting. preparing the assembly, piece brazing alloy, 0.006 in. thick in. square, inserted within the joint the brass stud and the tangular brass tube. “Handy” flux then painted the parts joint, and the assemblies are placed the furnace conveyor. The time the controlled-atmosphere heating ber about min., and the furnace temperature 1550 deg. Fig. shows two photomicrographs, one low-power magnification (above) and one high-power (below), illustrat- ing the intimate union formed between the brass stud and tube this process. will observed that there has been complete solution the metals the This Copper paste Avoid vertical seams- copper runs away from them 58—Assemblies are gen- erally set such position within the brazing furnace that there will vertical seams from which the brazing metal can run force gravity. bond, traces the joint having en- tirely disappeared. Clips for Inaccessible Joints Inaccessible joints can sometimes supplied with brazing metal using clips made from copper strip foil. The clips can formed into odd shapes fit odd contours. They give surprisingly good results certain tvpes work. Use clips refrig- erator evaporators was illustrated 59—A piece copper foil melts and runs down the surface the upper half-shell this refrigerator float and collects the mid seam, where strong, tight bond made. page Slugs Brazing Metal are Handy Slugs brazing metal are com- monly employed and they sometimes have advantages over rings. Slugs can made from short, cut lengths copper wire strip. For produc tion job they can all contain the same amount brazing metal, thus con- tributing uniformity. the refrig- erator exhaust muffler, shown 64, copper-wire slugs are dropped into place during with greater ease than copper rings could inserted. Thus, the applying copper the joints negligible cost because the time dropping the slugs place shown copper slug placed top bit being furnace-brazed steel shank. When the copper melts flows over the en- tire bit and runs over the edges into the joint. such assemblies the bits Foil washer NN Loose fit permit Foil settling down 60—Foil used brazing metal. shows foil washer the joint refrigerator crank. suggests loose fit allow upper member settle down and take voids. alloy wire. Fig. shows scheme sometimes used, whereby holes are drilled into the members and copper slugs are dropped into them when assembling, previous furnace-brazing. would difficult supply copper these joints satisfactorily any other way. \lso having the copper flow from the inside out, completion the braze indicated the appearance the copper fillet around the joint. For best results quite important that the abutting surfaces these members square, flat, and clean. Slugs, long lengths, can cut from copper wire machines such made the Artos Engineer- ing Co., mentioned above. Electroplating Also Useful electroplating the surfaces members before assembly, some prod- ucts can furnace-brazed without further addition brazing metal. good example this the Bundyweld double-walled steel tubing shown Fig. 35, [Iron Ace Sept. 22, page 48]. get successful results, with the plating serving sandwich filler, such within sleeve joint, the plating must quite thin and the sec- tions the parts must thin that they can quickly heated. With this combination, only short time the heat required and the assemblies can gotten out the heat before the small amount available brazing metal goes into solution with the steel and partially completely disappears. there heavy layer plating within the joint, the steel surfaces are held apart this laver and they never have opportunity knit together and form strong bond can obtained they are intimate con- tact. Also, there possibility that THE IRON AGE, November 24, Vertical refrigerator crank was furnace brazed using foil washer the joint indicated the arrow, the manner shown Fig. 60. ABOVE piece Sil-Fos foil in- serted within the joint furnace braze this brass stud and brass tube assembly. The assembly brazed, then pickled shown the up- per right, hand; the final product, plated, the lower right. 32—THE IRON AGE, November 24, 1938 ABOVE AND LEFT silver-brazed joint between the tenon and tube the brass as- sembly shown Fig. 62. when the copper melts, will flow away, leaving voids which result weak leaky joint. has been shown. however, that some jobs can worked out very successfully means elec- troplating the proper combination obtained. Sometimes copper some other form, such wire rings, used augment electroplating. Fig. shows assembly which electroplating used advantage avoid the use copper-wire rings. When this product, automobile ig- nition switch made Briggs Strat- ton Co., Milwaukee, was first put into production, small copper-wire rings were placed over the tenons the two pieces which are pressed into the member. This proved slow because the rings were small and hard handle. Later, the cylindrical member was copper plated before assembly, and this plating sup- plied the brazing metal the joints fraction the former cost when using the rings. Electroplating the surfaces high-carbon carburized-steel mem- bers before brazing sometimes de- sirable order minimize surface decarburization caused the furnace atmosphere the high temperature. Molten Copper Sprayed Parts Copper practically any other brazing metal can sprayed the molten state assemblies preparatory spray gun. this device the copper wire fed into the gun, melted with oxy-acetylene flame, and blown upon the metal surfaces with consid- erable force. The brazing metal can laid whatever thickness de- sired. necessary, however, provide grit-blasted sand-blasted surfaces the parts that the par- ticles brazing metal will em- bedded the surfaces. Otherwise there will mechanical bond and the layer might not adhere. ap- plication this method was shown Fig. [Iron Ace Sept. 15, page 33]. Typical oxy-acetylene spray guns are the following: The Mogul Metal- lizer gun, made the Metallizing Co. America, Inc., 562 West Washing- ton Boulevard, Chicago, and the Meta- layer gun, made the Metals Coating Co. America, 495 North Third Street, Philadelphia. Copper Applied Paste Form Copper-powder paste valuable tool the furnace-brazing process. Its chief advantage considered its ability applied out-of- the-way places assemblies where impossible apply copper wire any other handy for preparing “underneath joints” where copper-wire rings cannot made stay place because their tendency fall away. convenient use o> 4 « i * for fastening copper rings place because hardens readily. Some- times used auxiliary supply brazing metal along with copper some other form. The copper paste mixture pyroxylin solution, thinner, and copper powder, mixed suitable consis- tency that can applied readily the assemblies, usually with small brush, However, wire rings, foil, slugs, etc., are less expensive than paste and cost less apply, they are used wherever possible. Also, they are more desirable than paste from the standpoint uni- formity amount. They can in- expensively formed machine, and the quantity copper obviously will always the same. impractica- ble for operator apply the cop- per paste evenly equal amounts all assemblies. Used Hold Rings and Slugs Place Sometimes found that wire rings slugs can held position nicely small quantity the paste because hardens quickly and forms good binder. Otherwise, the rings slugs might tend slide away from the joints from handling the assemblies around the shop when within the furnace. The paste generally contains copper powder when used for this pur- pose desired obtain the extra action from the copper pow- der. Sometimes only the lacquer and thinner are used cement the rings slugs place. When employing short-time braz- RIGHT 64—Slugs braz- ing metal are fre- quently used advan- tage. shows two slugs dropped into refrig- erator exhaust muffler; tipped with tungsten- carbide. — ABOVE 66—Electroplating with copper the cylindrical member the cen- ter avoids use small wire rings the two tenons and lowers prepara- tion costs. ° ° ° LEFT ding slugs brazing metal holes within joints sometimes conven- ient way get metal where needed. type copper-brazing furnaces, the cop- per paste sometimes leaves ash carbonaceous deposit the surface the steel after brazing, which some- times requires stiff brush for re- moval. This deposit the surface the metal, many cases, not ob- jectionable. But where appearance cleanliness factor, the smooth even flow from copper some solid form gives much more desirable result than can obtained with the copper paste. When brazing with long time- cycle, the deposit sometimes left the assemblies the paste will generally disappear and parts prepared come from the furnace clean and bright. The fact that copper can applied the paste form wherever necessary one advantage using copper the brazing metal steel assemblies, instead using the lower-melting a Tungsten-carbide alloy bit Steel shank Copper slug alloy tie wires Wire rings alloys. brazing with alloys such brass, powder-paste not prac- ticable because the low-melting con- stituents the alloys, such zinc, vaporize very rapidly from the pow- dered metal and then becomes almost impossible melt the brazing metal anywhere near the supposed melting point. other words, when brazing with paste made brass powder, necessary run the furnace prac- tically the same temperature for copper brazing, and the results might not nearly good when using copper. addition, flux needed with the brass while none ordinarily required for copper. When brazing parent metals which are not easily wetted the copper, such cast-iron, alloys containing chromium, manganese, vanadium, sili- con, aluminum, sometimes ad- vantageous mix small amount flux with the copper paste. The flux assists the copper flow. Paste Mixed Small Containers The copper-powder paste should mixed small container, and should stirred frequently keep the pow- der suspension and thus assure that copper daubed the assemblies along with the lacquer. cover desirable when not using the mixture, retard the tendency jell due oxidizing action with the air. Once the mixture jells dries cannot restored and reclaimed only high cost, hence the desirability small containers. general, the mixture consists about one part each pyroxylin solu- tion and thinner, plus sufficient cop- per powder give good con- sistency. With little experience, the mixture can made guessing the proportions rather than taking the pains make quantitative mea- surements. (CONCLUDED PAGE 65) THE IRON AGE, November 24, 1938—33 | - Copper holes UTANE tanks, them, now be- ing with zinc Wilmington, Cal. Sprayed Zinc for Protection RICE Manager, Process Development Depart- ment, Metallizing Co. America, Los Angeles corrosion dustry. The application zinc iron and steel has provided ade- quate protection for ordinary weather conditions. The method most com- monly used has been hot dipping, usu- process satisfactory and economical but limited (1) size items that may treated molten bath zine, (2) maximum deposit 0.0025 in. thickness, (3) distortion caused high temperature molten metal im- lipping the entire object portion defective. these exceptions the zinc hot dipping proc- from atmospheric corrosion wherever the various types paint have been inadequate. Metal Spraying There another method apply- ing zine that does not have the physi- cal limitations hot restricted only comparative costs. and has overcome this objection known metallizing metal ing, employs oxy-acetylene flame melt zinc wire and compressed air blast atomize and impact the molten IRON AGE, November 24, 1938 zine particles the surface seldom competes economi- ments, but with the single exception cost has practically limitations application. Coatings plate areas may total 0.015 0.020 thickness de- sired, small large structures regard- less form size may distortion from high temperatures necessary, and any portion item may sprayed. Bonds are ap- proximately similar efficiency metals that may hot dipped, but applied and bonded metals. Quality deposits are almost equal corrosive resistance per unit thickness according the customary laboratory and field tests, although one contains greater amount zinc oxide frequent dippings clusions galvanizing. The atmospheric corrosive that cannot use the hot dip zine process has predominately used paint simi- lar compositions often combined with pulverized metals. Such applications are low initial cost but under some the more active corrosive conditions protection short duration and average annual costs are comparative- high. Exposure adjacent large bodies water, low alti- tudes tropical semi-tropical lo- cations invariably disintegrates paint protectives from one three this field the use pure molten zine applied metallizing indicates economical and superior protection. process bridges, upper vessel struc- tures, and many other objects for the past vears. For British and German consumption Upper portions the naval vessels several Eastern countries are metallized. The has sprayed-zine its entire venti- lating systems, refrigeration plants, fireproof bulkheads, and funnels. The initial cost greater but much l