The Iron Age 1922-03-23: Vol 109 Iss 12

THE IRON AGE New York, March 23, 1922 LISHED 1855 VOL. 109, No. Polishing of Metals an Art in Itself’ Lack of Standards Attributed to Lack of Appreciation of oF What the Problem Means—Major Importance of the Lowly Glue Pot BY SIDNEY G. KOON / about 1876, began the real need for giving it must be regarded merely as a stepping stone or metals a polished or refracting finish which preliminary operation to the real finishing or polish- would take from them the crude, rough appearance’ ing processes. W [H the start of the nickel plating industry, far superior to that left by the lathe or planer tool, left by the preliminary processes and develop their Polishing may be regarded primarily as flexible inherent beauty. From small beginnings, the busi- grinding, in that it is accomplished by means of ness of polishing and highly finishing metals has emery or other abrasive held by glue on the pe- grown in a cumulative manner, and has lately-re- riphery of a flexible wheel, made usually of cloth ceived a considerable impulse from the disinclina- or leather. Buffing, on the other hand, while done Dotted Lire Shows “\\, face of Wheel \\\ Headed wth Emery Polishing Two Special Faced 16-In. . ° . : i Brass Door Knobs Compress Canvas Pol- on One Specially ‘Shing Wheel of Hard ( ; | Shaped Cams aims Density, Used in Fin- t a) ; ae press ishing Scissor Handles ae Canvas Wheel. The ‘The sketch shows how ¥ knobs revolve while the emery heading fits ‘ being finished the wheel contour 1 <, buyers to purchase materials which lack with tripoli-rouge, lime or other abrasive powder, 8 i finish. and producing the most highly finished product pos- “a Manufacturers, feeling this condition of affairs sible, does not have the abrasive firmly attached to ; through the inability of their sales departments to the wheel. In buffing the abrasive is applied during maintain an adequate volume of sales, have not been the process by means of a “cake,” using wax or 5 ) learn the cause, and to look about for means grease as a body or bond, and held to the wheel, ae ' giving their products a satisfactory luster. whence it is transferred to the part being treated. j (ae Where they have succeeded in this effort, they have It is thus rubbed in by the application of the buffing Bi D¢ ‘le in many cases, during the prevailing de- wheel. n, to hold their customers and add new ones, There has long been much confusion in connec- preserve a better proportion of their sales tion with these treatments; many people call them ive their less fortunate neighbors. indiscriminately by either name. Hence, it is per- s element of sales resistance is centered ulti- haps not strange, in view of the recent development ery largely in women, who want everything of the processes, and the utter lack of general in- household bright and shiny. This attitude formation about them, that encyclopedias, even ot only to kitchen utensils, but to door- those devoted primarily to mechanical subjects, do nd other house hardware and a multitude not clear up the matter. The paucity of written things which formerly were left dull. The information in this field is extreme, There is no polished nickel-plated electric iron, as com- book dealing adequately with it, nor are there many ith the rough black flat iron of a generation magazine or other technical articles which cover it, a familiar example. except in fragmentary form. ding with a solid wheel of emery or other An idea of the importance of polishing opera- e has been used for a long time as a shaping tions to the metal working industry may be obtained hing operation. While this leaves a finish when it is realized that about 85 per cent of the cost of making pocket knives is represented in the from an interview with Bradford H. Divine, finishing operations. This leaves only 15 per cent vine Brothers Co., Utica, N. Y for the material, the forging, grinding and other 777 ed pega Ce Cee + abo Ce Md 2 Bin pan ~ n a aan cenaggete seid = er he aie G AION ate I gic pM Lg RO Ilha BALES , par i 778 THE IRON AGE Seashennncaneevssiecnonsenevenicevereueenearennsans cvenasessseensenenennens /enuunesten LeEee bOPORESUOODEATREEIOENG sOOORELATLA( HARHIN cK ORNALINENICHREUDIOLCOTORDIORONELTSOLOUDIEEMDTIENY da man calls it “buffing”; another says it is “polishing”; still a third refers to “fexible grinding.” Confusion of terms implies lack of standards. Lack of standards connotes enenensavacervennersany —in many plants—lack of interest. And lack : of interest is the forerunner to loss of profits. When five-sixths of the entire production cost of a pocket knife is incurred in the finishing operation, up-to-date management realizes Mo ht that that finishing operation deserves the most expert attention and painstaking skill reese snenesvocuarereesacranvecnossocneenisity ponenoaanetineseriue which money can buy. It demands equipment properly fitted, in all its details, to the par- ticular operation to be done on that particular job. eevee enesc renner nernnanentT processes. Due doubtless to a lack of realization of its importance, the polishing operation of the usual metal working plant has been neglected to such an extent that this has been characterized as the one department of modern plants which is not run in accordance with modern’ engineering methods. The beginning of the importance of polishing was simultaneous with the advent of the nickel- plated bicycle, which was followed almost immedi- ately by nickel-plated faucets and other plumbing fixtures. From this starting point, the process has passed to a myriad of uses, until to-day a very large proportion of metal parts for final use have to be polished. It may seem a far cry from the small blade of a pocket knife to a locomotive bell, m4 an I } k h i \ k \ \ \ h Special Compress Polishing Wheel for Finishing Simul- taneously Two Parallel Surfaces on a Lathe Guide The two other inclined parallel surfaces may likewise be finished simultaneously with this same wheel, merely by changing the setup. Note that the wheel consists of annular rings, held in place by special clamps and bolts but both are now treated largely in the same man- ner, under modern methods. Solid grinding does not produce a truly finished surface except in some forms of high precision work. Even then, the rigidity of the abrasive wheel is likely to produce scratches on the surface. Car- borundum crystals are prone to dig in. These troubles are avoided when flexible grinding is used, March 23, | 9292 because of the smooth running of the whe: because the mere property of flexibility in the e] prevents the resistance to its passage acro part being finished from becoming sufficient to scratches. Engineers, who have given this subject « ishing practically a lifetime study, hold posi that the entire proposition of abrasive finishing processes, from whatever angle « ered, gets back eventually to the character | quality of the glue used in tying the abrasi the wheel, and to the method and care by the glue is applied to the wheel. It is perfectly obvious that the glue must the abrasive particles tightly in position, for a Special Angles for Construction of R Are Polished Wheels, One F the Other. Both cial 14-in. diameter press leather The roughing wi medium density, }! grooves; the wheel, medium |} but two. This is theory that the — on the rougher op will wear away quickly ; hence the w were designed for an Cushion amount of service befor redressing quite impossible to do a satisfactory polishing or flexible grinding job if particles of glue and emery fly from the rapidly revolving wheel onto the floor. And the resultant of the wheel and its peripheral velocity must give a hardness sufficient to cut the metal, or the cost will be increased, a satisfact production volume not reached and the desired ish or luster not obtained. At the same time, th glue has to be flexible enough to bend slightly Two Wheels with oe Plain Contour Pol- ish Simultaneously 7 _ the Edges of the ; Handle Stem of the Scissor Blade, the Blade Being Held in a Suitable Jig. The third wheel, shown in a differ- 2 ent plane, is used to . polis! h the handle, as indi- cated by the dotted line A otherwise the wheel ceases to be flexible and the process approaches that of solid grinding. These two functions of the glue, seemingly almost dia- metrically opposed, can readily be obtained in 4 glue manufactured especially for this purpose 1! accordance with standard formulas. They are 4l- most certain, however, not to be obtained from the general-purpose glues on the market. T Grinding, polishing and buffing are all alike in the fact that they are all performed with whee's. Beyond that point, they differ materially and each in itself has differences due to the character of March 28, 1922 he work to be done. For instance, coarse grinding used for removing scale and humps from the irface of the metal. Medium grinding carries the rocess one step further and reduces the surface to . certain degree of smoothness. Fine grinding is ised for precision work and for leaving a perfectly nooth surface for the following operations. There no definite dividing line between these three ‘esignations of coarse, medium and fine, for there re many grades of fineness of abrasive wheels from the coarsest to the finest. Similarly, polishing may be classified about in -he same way as grinding, into coarse, medium and the coarse and medium being similar in the esults desired to the coarse and medium grinding. Fine polishing, sometimes called glazing, grease ishing, ete., is used to prepare on non-ferrous tals a surface which will later be buffed or plated. [eo os asennnens FB eeennnes mae iped Compress Canvas Wheel, 12 In. in Diameter f Medium Hard Density, Used in Finishing Gear x Hanéles. The handle rotates at a speed different from that of the polishing wheel [he final and finish polishing, when applied to bare steel, is often called buffing. Buffing may also be divided into three groups, coarse buffing consisting in cutting down non-fer- us metals, this operation being done often direct yn the casting as it comes out of the sand. Fine or medium buffing follows the rougher process and produces a smoother finish, which may later be car- ried further. The final or finest buffing process, known as coloring, is used to produce high light Sb ~ \ M46 4 t I » Get Up Into the “ \ : : | Neck Section 2 i Hoe Blade, an < Acute Angle Is % C -ded on the Y : of the Wheel. fy is a_ special , S composi- ——— K/hoe tion wheel efracting surfaces on either bare metal or plated ware, Polishing is governed first by the character of ne metal being treated. A second governing point, d furnishing a sub-division within each class of netal, is the type of article to be polished. The iird governing factor is the contour of that article, which governs not only the density of the wheel the shape of its face. The fourth and final verning characteristic is the finish which it is ‘sired to obtain upon the metal part. . The character of the abrasive to be used depends m the amount of metal to be removed, resolved to the number of processes necessary, as well as ‘he character of the finish to be laid on the metal. 1@ size of the abrasive depends on the character W . HEN the sales manager finds a competi- ' ’ or cutting into his customers with goods : of a superior finish, then is the importance of ; proper polishing driven home with compelling ' force. This is purely an executive problem. i The engineering and production elements have : all been reduced to standards—but not in every i : shop. Where finishing technique and methods ' : are still left to Tom, in one shop, to Dick and i : Harry in the others—there is the place for | ; the expert in polishing to advise with the i : management and show how dollars may be saved, and others earned, through modern methods untrammeled by precedent and in- ; ertia. or fibrous nature of the material being polished, and on the fineness of the surface desired. Whether natural or artificial abrasive is used depends upon the amount of cut required and whether or not the process is designed for a reduction of the metal. Artificial abrasives are used almost wholly in the cutting process, while the softer natura) abrasives, with a certain admixture of dirt which it is difficult to remove from them, but which seems to help 4a: . adn meal ail AIS br OODIIIII’ sada bag Les Uji WA A N } } } Lie A hhh j LA As | a) VAL | | i] | THAT / i yr £ y AT ih al 2 h NK : } eS t H y or Nt He yi 7 S q WZ Z te ae ‘ . ~~ TS aoe a eg oN A ss N } ' & SS = i) Ss ; 7 ae K } NS noel E 1 ; Y { > _ >>. Vy } os ee kp nies 7; ‘7 Vj ft 7 ' (< 4 - é Rough and Dry Finishing on Five Surfaces Simultaneously by Means of Special Sectional! Compress Polishing Wheel Designed for This Particular Job lubricate the process, are used for producing a fin- ish on the surface. Wheel speed is controlled by the same conditions, and is a matter of greater importance than is gen- erally understood. The limit of operating speeds is controlled by the melting or softening point of the glue used, which action in turn is produced through excessive friction between the wheel and the metal, and through the crushing or glazing of a ae 4 a ‘ rer ea RS tend a baannnatediibed oe ee any 11 Pn SEM RAG AES ALT AE AFI OS 5 ° 5 ~ : > ~ ee ote ‘+ *- ea ae Eg aR Sty Neste 780 THE IRON AGE the abrasive particles. But there is no occasion, in general, to approach this limit. Far lower speeds are called for in many instances than are commonly used and, in these cases, the high speed of usual operation will not produce the finish desired. Upon the surface to be covered depends the di- ameter of the wheel. Its speed depends upon the Wheel Travels Automatically at Right Angles to Work. * wed Adjustable for Pressure 3 Mecharically Diver | n ‘ 74) Fic 6 Diam.» 3/ Long ay Ay eft hh 5 “Copper Roll if x? Z / I lt | af (SX Bi G an FAL / x \ iis a = BC = | lathe = 2_& Because of the Nature of Soft Copper, Which Would Tend to Clog a Polishing Wheel Rotating in the Same Plane as the Engraving Roll, This Concave-Faced Compress Canvas Wheel, with 2-In. Cushion and Extra Soft Density, Has Been Mounted at a Right Angle to the Work. The wheel is 16 in. in diameter, with 4-in. face; the copper roll 16 in. in diameter and 31 in. long desired results for the several processes necessary to the completed article. The density of the wheel is governed by the shape of the article. The shape of the wheel, that is, whether the face is flat or formed, depends upon the contour of the surface to be pol- ished. Our illustrations show a number of wheels designed for certain specific contours and fitted to those only. A typical example of the sort of problem to be met in connection with polishing of metals may be drawn from the experience of a prominent optical company, which required a highly polished surface, absolutely true in a plane, for the comparison of lenses. Attempts were made to get this surface ; —_| -x ony Ni . : Two Polishing Operations WS Performed Simultaneously on S a Knife Blade by Special ky Medium Density Compress k. a Leather Wheels 14 In. in oo Diameter. One wheel has shaped contour: the other, while plain in contour, is t undercut to clear the heel of = ‘Ss the knife blade by the usual planing, followed by polishing with a very fine wheel, while the piece was held by clamps upon a planer. Invariably, however, it was found upon removing the piece from the planer that a certain amount of distortion had been set up, by the combined action of the restraining clamps and the heat of the process produced by the passage of the polishing wheel over the surface. Consequently, the familiar rainbows appeared when the plate was used. In search of better methods of handling the operation, the engineers avoided the use of clamps by holding the piece in place on the planer bed by means of hot pitch, and polishing after the pitch had set. Still the rainbows appeared when a lens March 23, 19° was tested. This was due to the fact that the hx ing of the metal by the action of the wheel produ a local, though minute, heating of the pitch, and caused the almost microscopic distortion of metal. A solution to this problem would be to bri both sides of the metal plate to as nearly as possi! a uniform and plane surface, the two being para! to each other, and then polishing one surface wi; a polishing wheel while the plate was held by | other surface magnetically on the planer bed. ‘} polishing under this condition can be done wi great nicety, care being taken so that the amou of heat previously experienced is considera diminished. This illustration gives a clear indi: tion as to the character of accuracy required some polishing operations and as to how this a curacy may be obtained. In another instance, a firm manufacturing foil equivalent to about 1/3000 in. thick only. 1 final rolling process was done by a roll 7 in. diameter and 17 in. long, made of hardened ste: and highly polished. It was found, however, t! Polishing Wheel ‘stee/ Roll 2 Diam.x B face . f /7x7 Diam Hardened * Wheel Mourted on Lathe Carriage Method of Polishing Hardened Steel Rolls Used in the Manufacture of Tin Foil after a few days’ work the roll began to give streaks, or tiny scratches, in the surface of the tin foil, which was a condition unacceptable to purchasers. Consequently these rolls had to be changed fre quently and redressed before again being used. This redressing was done by a skilled operator, who smoothed the rolls by means of abrasive on a leather surface mounted on a block of wood, and applied b) hand to the roll. The operation took him thre: weeks and, while it resulted in a smooth surface, produced an exorbitant upkeep cost. . This problem is being met by a flexible grinding equipment, shown in one illustration, where a pol- ishing wheel 12 in. in diameter, and with a fac of 11% in., runs back and forth on a lathe carriage while rotating at high speed against the surface of the rotating hardened steel roll. The use of a proper abrasive on this wheel produces the surface desired, while the continuous rotation of the stee roll, on a fixed axis, insures its perfectly cylindrica form after the conclusion of the operation. It is estimated that by this means a roll may be re dressed within 30 minutes, instead of requirins three weeks. Frequently it. is necessary, in connection wit! polishing operations, to go back into the previous history of the manufacture of the article to be po ished, and make some change in the manufactur! process so that conditions prejudicial to polishi: may be avoided. This study of preliminary pro esses frequently results in a change in the shape of the piece, so that the polishing may more easi! be done. Sometimes this results in the use of « larger amount of metal in the piece, which, 0! course, is rarely favored by the manufacturer. When it is made clear, however, that the use of an March 23, 1922 iditional dollar’s worth of metal may save ten ilars in the finishing process, the desirability of he change becomes apparent. These pages contain a number of sketches show- To Get into the eee ae Angle of a Bicycle : Handle Bar Post a Wheel with Beveled Contour Is Neces- sary This one is 14 in. in diameter, with 3-in. cushion, of compress canvas ind soft density y - ’ > r typical polishing processes applied to a great riety of products, all the way from surgical scis- rs and pocket knives to lathe beds and other heavy eces. Each one is a problem in itself and each ne has to be separately studied. As an illustration f this, mention may be made of skate blanks turned it by a Massachusetts concern. They were cut it by dies from thin plates or sheets of steel. It happened that the manufacturer blanked the blade for the heel risers with one side of the sheet upper- st, while the toe riser was cut with the other side uppermost. The result was a piece so warped that it could not be held on a magnetic chuck, either tor removing the burr, by grinding, or for polishing. fhe remedy was obvious. The foregoing illustrations may serve to bring clearly to the attention of the executive end of a anufacturing concern the fact that the possibil- ties of accomplishments, both mechanical and finan- ial, in polishing departments, are fully as large as an we mm b CP KTS Z| A 5] *) By} Wr Je mm ~ I} yy . Le] x I Wi awd] NI | PRuAS—™_] we me i 4 gel Sey Wor” 4 ! Work Rest Gear or belt Driver Feed Roll Trualy (Orive Gear not shown) === Adjustable ih Both Vertical and = Honzontal Planes. To Increase Speed A= or Feed. Swing Roll at B Vertically Polishing Pipes or Tubes Which Are Fed Across he Face of the Polishing Wheel by the Feed Roll Held Askew y other department in the factory. The actual lishing processes themselves have been reduced to ich absolute standard formulas that they are mple of introduction and execution. The basis of nese processes, however, is a general knowledge of | other processes preceding polishing, in order to ring the work through to the polishing or finishing ‘partment in such condition that it can be properly perated upon and proper results secured. It will appeal to the reader, no doubt, that a man vho may have spent a lifetime in a plant as a polish- er has not had the proper education, experience or raining to permit him to do other than simply sit -C his polishing wheel and polish a piece of metal. THE IRON AGE 781 Planning the work requires the best kind of tech- nical training and manufacturing experience. A man, to be a competent executive in charge of a finishing department, should have a thorough knowl- edge not only of metallurgy, including the effect of various processes, such as heat treating, upon metals, but also of forging, casting, drawing, stamp- ing, spinning, etc. He should have a comprehensive knowledge of the design of metal parts, having in mind the ability of the operator to reach every por- tion of the article with a polishing or flexible grind- ing wheel of the size, shape and character necessary to produce the desired finish. Much could be said on the question of cost of operating finishing departments. It is true that, especially in buffing, the whole plan is so funda- mentally loose to-day that enormous wastages, all of which are part of the cost, are present and foolishly so, simply because the proposition in the plant has not been standardized. It is, indeed, difficult to find two concerns, even in the same line of manufacturing, using the same process; and often they are operating at widely different costs. In connec*ion with this, much of the work previous- ly executed, undoubtedly by hand, is now being handled on automatic and semi-automatic machines, with the obvious advantage of decreased cost and increased speed of production. Shaped wheels are coming rapidly into use, fol- lowing along the princples of milling machine prac- tice—for what is polishing, except another phase of metal production expressed so clearly in milling operations? Likewise, polishing is taking the place of lathe and planer operations, and, more generally speaking, flexible polishing and grinding are being substituted for other tooling operations at great reduction of cost, and are at the same time pro- ducing satisfactory finishes. Progress in Molding Sand Investigation The American Foundrymen’s Association commit- tee on molding sand research has been formulating instructions to be sent various State surveys as to methods to be followed in their investigations. The sub-committee on standard tests will report in due time on standard methods which will make possible a comparison of sands of one State with those of an- other. The committee desires information concerning investigations which have been carried on in foun- dries and laboratories in the testing of molding sand and the reclamation of old sand. The American Steel Foundries, Sivyer Steel Casting Co., Buckeye Steel Casting Co. and Ohio Brass Co. have already offered to contribute the results of tests made in their foun- dries. Three representatives of the American Society for Testing Materials have been appointed to repre- sent that organization on the A. F. A. committee. They are G. K. Burgess, Bureau of Standards; G. H. Clamer, Ajax Metal Co., and Dr. Richard Moldenke, Watchung, N. J. The secretary of the committee, R. E. Kennedy, 909 W. California Street, Urbana, lll., would like to be notified of any investigations that are being carried on by foundry companies or individuals. The Pendergast Fence Co., Ltd., Sarnia, Ont., has begun operations in the manufacture of wire fencing. The plant is equipped with new modern machinery. The president is Maurice De Pendergast; vice-presi- dent, Archibald Weir; secretary, Judith M. Pender- gast, and treasurer, Harvey Unsworth. Maurice De Pendergast started the manufacture of wire fencing in Sarnia in 1903 and the business gradually developed, but has been out of business for a few years preced- ing the organizing of the new company. He is also president and principal owner of the Pendergast Fence Co., Inc., with head office and a plant at Stillwater, Minn. ce Ree eee _ oe ee ee Se ee decane th Lane stg See MRIS Brae. ce a = Be Ir teas ee oo Pe a a acs F when Ras eet aaa. ~ sania gf Aa ame tt, ELECTRIC STEAM GENERATOR An Apparatus to Take the Place of Fuel-Fired Boilers A N electric steam generator, utilizing the principle of heating produced by resistance to flow of electric current through water, has been placed on the market by the Electric Furnace Construction Co., Philadelphia. It is called the Electro steam generator. Steam is generated at any specified pressure by means of high tension alternating current led directly An Electric Steam Ge 3-Phase, Instal'ed b nerator of 20,000 Kw., 6600 Volts, Shawinigan Water & Power Co through electrodes of special design into the water to be evaporated. A vertical tank is used, constructed ac- cording to approved boiler practice. The whole ap- paratus occupies, it is emphasized, only a fraction of the space required for fuel-fired boilers and the cost of installation is much less. The amount of steam generated, the pressure and amount of electric power used are governed by the height of water in the vertical tank. This is controlled and regulated by standard valves, thus to render the whole operation practically automatic. Any water that is suitable for the ordinary boiler is satisfactory and it is not regarded as necessary to install water softening apparatus. Either condensate or raw water can be used or a mixture of the two. No part of the electric steam generator is exposed to a higher temperature than that of the steam and the only part subject to wear is the electrodes. The most important application of this steam gen- erator will be found in industries located within the range of hydroelectric power plants, where use may be made of surplus energy or water running to waste. Due to the inability of ordinary power consumers to operate 24 hr. per day, the load factor at most power plants runs from 60 to 80 per cent. Complete use may be made of this off-peak load, which is not now used, by the installation of such steam generators, and the load THE IRON AGE March 23, 192° factor of the power station can be considerably proved. The generators are found to operate with per cent thermal efficiency and unity power fac: The generator can be paralleled in with existing c or oil-fired boilers and operated on the off-peak loa when cheap power can be had. One large installation operates only on Satu) night and Sunday, and the resultant saving in coa is stated, paid for the whole cost in one season. The chief advantages claimed are that the inj and operating costs are much lower than on fuel-fi: boilers, the space occupied is much less, minimum . penses involved for buildings, and smokestacks, s|{ age for oil or coal, fuel or ash-handling equipment, n chanical stoking devices and water softeners are needed. Renewals, repairs, cleaning and shutdowns a reduced to a minimum as the highest temperature that of the steam. A number of large generators have been in succe ful operation for some months and already ov 100,000 kw. of generators, representing 10,000 bo horsepower, according to Frank Hodson, president El; tric Furnace Construction Co., are running or being i stalled of the type described. Wherever fuel is expensive and power can be had at cheap rates, the electric steam generator is regarded as the economical unit. This condition applies particu larly to industries like paper, pulp and chemical, lum ber, textiles, etc. Many companies purchasing power contract for blocks of electric power at a fixed rate per horsepower year. Yet few of these use this continuous ly, it is pointed out, and during idle periods the energy which they pay for can be converted into steam for heating or industrial purposes. Air Reduction Sales Co. and Davis-Bournon- ville Co. Merge The Air Reduction Sales Co., Canadian Pacific Building, New York, and the Davis-Bournonville Co., Jersey City, N. J., have consolidated. Plans which have been under way for several weeks were ratified at a meeting of the stockholders on March 17. New of ficers of the consolidated company have not yet beer elected, nor have complete arrangements been made regarding the physical merging of the plants of the combined companies. The Air Reduction Sales Co. was incorporated 1915, acquiring its processes for the production of gases from liquid air largely from the L’Air Liquid Societe of France, and it owns exclusively the rights t these processes for the United States and Mexico. I) addition to plants scattered at various industrial cer ters throughout the country for the manufacture of oxygen and acetylene, the company also markets the entire output of a plant in Baltimore, Md., operated and owned jointly with the U. S. Industrial Chemica! Co., for the manufacture of calorene by a process de veloped by the two companies. It has a plant at Jer \ sey City for the manufacture of cutting and welding torches, and a plant in Chicago for the manufacturs of acetylene tanks. It has warehouses in 35 cities of the United States. The Davis-Bournonville Co., which has a plant at Jersey City, is a pioneer in the development of oxy acetylene apparatus and equipment, its products 1 cluding the “Oxygraph,” the “Radiagraph,” tube weld ing equipment and other special devices which will be combined with the “Airco” line of the Air Reductior Sales Co. At the annual meeting of the Engineering Adver tisers’ Association, held at the Great Northern Hotel, Chicago, March 14, the following officers were elected for the coming year: President, Julius Holl, assistant to president and advertising manager Link-Belt Co Chicago; vice-president, J. B. Patterson, district man ager P. H. & F. M. Roots Co. at Chicago; secretary, H. N. Baum, advertising manager Celite Products Co., Chicago. Fluorspar in Open-Hearth Practice Effective Agent in Removing Sulphur from the Steel— Action on the Slag and Furnace Lining—Some Old Ideas Altered hearth process for many years, but very little is known as to the reasons for the effects it about. It has been found useful in helping to the sulphur in open-hearth heats, and in this ection a paper by S. Schleicher in Stahl und Eisen, 17, 1921, is of great interest, as it deals en- with this question of desulphurization and the of fluorspar. Table 1 are shown the results with nine heats from material very low in manganese and high ilphur, and in the working of which no fluorspar used. The last column shows the sulphur distribu- coefficient and is obtained by dividing the sulphur tent in the slag by that in the steel. In other , it shows the ratio of the sulphur in the slag hat in the steel. ~~ Lon Ue UA DONOE LEED ODHRUOEEUROUED OED OROONDOEURRREREREBOOHEDO DERE UCURNOOEROODONOO Ter ornate rienNeETOoNoNT Subiline Contents of Heats Made ‘csithout Sixeebue P hearth pro has been used in the basic open- <q Analysis of Metal manent ainioaie Mangan- Phos- Sulphur Distribut’n ese, phorus, Sulphur, in Slag, Coefficient PerCent PerCent PerCent Per Cent 0.56 0.04 0.06 0.14 2.33 0.47 0.03 0.08 0.27 3.37 0.56 0.07 0.08 0.19 2.37 0.53 0.05 6.09 0.34 3.77 0.53 0.04 0.09 0.35 3.90 0.53 0.06 0.08 0.20 2.50 0.44 0.04 0.08 0.26 3.25 0.50 0.03 0.09 0.32 3.50 0.44 0.04 0.09 0.30 3.33 The distribution coefficient of these nine heats aver- 3.15. Table 2 shows what a different result is ed when fluorspar is used and gives the analysis ne 30-ton heats, as before, using the same lime rge but with addition of 400 kg. (882 lb.) of fluor- \vosonveervacnaannsaraanesevmnoestenvenrsrneesnsenvysvervensevannvoesoomenn evreerraresnenennenin ' Sulphur Contents of Heats Made with Fluorspar Anal lysis of Metal Mangan- Phos- Sulphur Distribut’n ese phorus, Sulphur, in Slag, Coefficient Pe rc nt PerCent PerCent Per Cent 0.38 0.02 0.05 0.32 6.4 0.47 0.03 0.05 0.32 6.4 0.32 0.02 0.04 0.30 7.5 0.50 0.05 0.06 0.38 6.3 0.47 0.02 0.04 0.26 6.5 0.44 0.06 0.05 0.30 6.0 0.53 0.04 0.03 0.20 6.6 0.41 0.02 0.05 0.33 6.6 0.47 0.03 0.06 0.36 6.0 ‘IVT LU TUL OPTETODUONAREDOREMMERENEDRT TOAD EN TEDD OL EEEOTRROREDREDOPTDOEEOTTORHNNATTRORREDETERDOATaNOFORREERHEG ITH ON EREDONEDONDED OTE: Che coefficient of these nine heats is considerably eased and averages 6.5. The steel of the first nine ts averages 0.08 per cent sulphur, which is above llowable limit of 0.06 per cent, while with the last heats it is about 0.05 per cent. The addition of par brings about a noticeable increase in the dis- ion coefficient and a decrease in the sulphur in stee!, “ie next matter to be investigated is the action of fluorspar in the slag. After its addition the slag es very fluid. If the outgoing gases are con- ted through water the well known jelly-like pre- ite of silica is formed which is always produced silicon fluoride is passed through water. The ‘spar has therefore reacted with the silica of the silicon fluoride being given off as a fume, and formed according to the equation: 2Ca Fle + Si0e = Si Fly + 2 CaO As silicon fluoride is formed, the calcium fluoride ‘uorspar contents of the slag must decrease. This own by the following results, the first sample : taken immediately after solution of the fluorspar; s, 10 min. after addition, and the other samples 783 at 10-min. intervals. The exact results of sulphur determinations in the steel, and calcium fluoride in the slag, were as follows: Sulphur, per cent.0.110 0.076 0.074 0.070 0.063 0.056 0.062 Calcium fluoride, per cont ...... 6.03 4.10 3.40 2.27 2.09 2.21 2.00 This shows that the decrease in calcium fluoride only goes on to about 2 per cent, the samples taken during the last 30 min. agreeing within allowable errors of analysis. Seven finishing slags from seven heats in which fluorspar was used were then examined. The results were: Calcium Fluoride Fluorine, Per Cent Per Cent 2.58 1.26 2.40 1.17 2.44 1.19 2.30 1.12 2.16 1.05 2.48 1.20 2.06 1.00 Here, also, with sufficiently long working, the cal- cium fluoride contents of the slag are reduced to 2.0 to 2.5 per cent, and then remain practically constant. Whether the fluorine is all present as calcium fluoride, or in some other form, was not determined, but the assumption was made that it was calcium fluoride. Up to now it has also been assumed that desulphur- ization, when fluorspar is used, was brought about by the slag being made more basic and yet remaining fluid enough to permit a good reaction. The following results will show that desulphurization cannot be laid to this cause. The finishing slags of two similar heats, one made without fluorspar additions and the other with fluorspar, are > given i in Table &. COOHEUITCU EET EROR ENO eROAD ERE RERE TS ORPPRERET EDGE” HERE NAAREUNETO UN OEROMERELDORTTTEND © FSP ERRORORED, Table 3—Open-Hearth Slags with and without Fluorspar Without Spar With Spar i acta eta Slag, Steel, Slag, Steel, Per Per Per Per Cent Cent Cent Cent SiOe 15.20 Cc 0.16 Si02 19.63 * Cc 0.12 FeoOs 3.57 Mn 0.50 FeeO3 2.86 Mn 0.41 FeO 8.14 P 0.03 FeO 11.57 P 0.02 AloOg 2.14 Ss 0.09 AleOs 3.36 S 0.06 MnO 5.41 MnO 5.63 P2O5 4.76 P2005 2.62 CaO 46.50 CaO 45.98 MgO 12.97 MgO 4.55 Ss 0.32 S. Coeff Ss 0.44 S. Coeff. ( as , xan 3.50 Cc mare 2.26 7.3 we ner PERERONOREREEE TF HEES 0m 1 LLEELLUETRREREEET ERE OEDODROOE, OU) 08820000 The haskell of the two » shame oxpuianel as the ratio of the oxygen of the bases to that of the acids is 1.67 in the first case, 1.30 in the second, and yet the dis- tribution coefficient in the first case is 3.50 and in the second 7.3 In order to obtain conclusive information, the follow- ing experiment was carried out: A 60-ton heat was taken, and while working down 2000 kg. (4409 Ib.) of spiegeleisen was added. In a half hour the manganese was worked out and the bath was in such condition that about a half hour’s work with the finishing slag was needed. An addition of 900 kg. (1984 lb.) of fluorspar was made, the spar containing 95 per cent calcium fluoride. Samples of metal and slag were taken, as shown in Table 4. Especially striking is the fact that the silica does not decrease but increases, notwithstanding the calcium fluoride reacts with the silica as shown by the thick white smoke fror: the chimney after each addition. To investigate the matter further, samples were taken from another heat giving results as follows: Test Time Silica, Per Cent 1 18 38 17.23 : 800 kg. (1764 Ib.) fluorspar 2 10:33 ° 17.65 - 3 10:°7 16.18 4 10:43 17.08 5 11:13 17.70 This heat also shows that the silica drops during the first seven minutes but then again increases. The slag takes up silica which must come from the furnace lin- ” rs a ad . ee ie senna anie tied US aes vs ees a Ak eh ta Bs on Pg inetd eo i ™ ight aiin ithgie! ea ie age Rach ne « . 784 THE IRON AGE ing, and it must be mentioned that there is marked destruction of that part of the hearth and walls coming in contact with the slag. Through the fluorspar addi- tion the slag has not become more basic. The sulphur in the bath (Table 4) is lowered from 0.081 per cent to 0.064 per cent and then 0.060 per cent. In the slag, however, the sulphur is not increased but decreases, and to a greater extent than is accounted for by the dilution of the slag with the spar addition. The same results were shown by another heat as given below: Sulphur in Steel, Sulphur in Slag, Time Per Cent Per Cent 10:55 0.081 0.233 11:00 S00 kg. (1764 Ib.) Spar addition 11:20 0.060 0.165 11:40 n.d 0.182 12:12 0.042 0.220 12:13 Tapped A careful balance of the sulphur in the heat given in Table 4 shows that 18.39 kg. (4054 Ib.) were vola- tilized. A test was carried out several times of tak- ing outgoing gas from the furnace between the port and the air regenerator, through a water-cooled pipe, and bubbling through potash solution. The average Table 4—Test with Steel Time Carbon Mangan. Phos Sulphur SiOe2 FeO 2:15 0.145 0.35 0.026 0.081 : 19.90 10.80 2:30 0.115 0.32 0.033 0.083 +: 17.90 10.67 2:32 Addition of 2000 3:00 0.175 0.44 0.0388 0.081 * 17.85 10.67 3:01 Addition of 900 3:11 0.120 0.38 0.027 0.064 : 17.60 11.44 3:21 0.100 0.33 030 0.060 : 2385 11.70 3:23 Addition of 300 ate 0.100 0.35 0.030 0.060 * 33.25 11.70 Tapped *Data in percentages showed 0.22 gr. sulphur per cubic meter, and theoreti- cally there should be 0.213 from the producer gas. Similar tests were made after the addition of fluorspar, but this method did not show an increase in the sulphur contents of the gas. This shows the sulphur is not in the form of SO.,, but there is the possibility of a fluoride being present, such as, for example, SF. There is a possibility that such a compound would be precipitated by the low temperature of the water-cooled tube, so the gas was sucked hot through a porcelain tube, and it was found that more sulphur was absorbed. The gas contained 1.966 gr. per cubic meter, and as 0.22 gr. came from the producer gas, the remainder or 1.766 gr. was volatilized from the slag. The amount taken for the test was 10 liters and the time was the seven minutes immediately following the fluorspar addition. The test showed, therefore, that the influence of fluorspar addition to an open-hearth slag regarding the lowering of the sulphur is that in some form or other the sulphur is volatilized, and the slag is there- fore in condition to take up more sulphur from the bath. The last mentioned tests show this clearly, the sulphur contents in the final slag being approximately the same as before the fluorspar addition, although previous to this it decreased. The sulphur in the bath dropped from 0.081 to 0.042 per cent. Where the slag is to be used for fertilizer, and it is necessary the phosphate be soluble in citric acid, fluorspar should not be used. Next comes an abstract of the paper by J. Fohs in THE IRON AGE, May 27, 1909, p. 1692, with the conclusions of which Mr. Schleicher is not in agreement, as they are contradicted by the results of the tests previously described. Under certain conditions, notwithstanding fluorspar additions, it is possible to get re-sulphurization of the bath, when there is a very rapid removal of carbon. An example of a 40-ton heat may be mentioned. The heat was very high in carbon and with a very thick slag. Ten minutes after the addition of about 10 per cent fluorspar to the slag, the metal after a good deal of foaming was soft. The sulphur before the spar addition was 0.048 per cent in the steel and 0.34 per cent in the slag. Ten minutes after the addition it March 23, {929 was 0.064 per cent in the steel and only 0.09 p, in the slag. Careful calculation showed that 1: (23.8 lb.) sulphur had volatilized. The finished showed 0.05 per cent sulphur, so the slag had a sulphur again from the metal. With soft heats, also, it has been found tha: might be re-sulphurization but only when spa added suddenly, in large amounts, to the finishin; In these cases there was always such a drop sulphur contents of the slag that the total of in metal and slag was decreased and sulp!} volatilized. In one case, of a 44-ton heat, aft addition of 700 kg. (1543 lb.) of spar there increase in the bath from 0.076 to 0.097 per cen: the sulphur in the slag dropped from 0.385 per cent. Calculation also showed that 18.6 (4 of sulphur was volatilized. It is evident that slag is in good condition to take up sulphur fro bath. For desulphurization, therefore, it is nec that, after the fluorspar addition, the heat remair ciently long in the furnace. The fear that too addition of fluorspar is harmful is therefore not Fluorspar Addition* Slag ‘evOg MnO CaO AleO3 MgO S P20; 2.14 17.07 38.80 2.08 6.16 0.21 2.68 2.71 16.77 39.30 3.16 6.35 0.25 2.52 kg. (4409 lb.) spiegeleisen 1.57 17.28 39.90 2.57 6.85 0.36 2.50 ke. (1984 lb.) fluorspar 1.57 15.83 34.65 2.36 7.29 0.26 2.29 t 2.14 16.25 35.18 1.90 6.65 0.25 Sar kg. (661 Ib.) spiegeleisen 2.71 16.02 35.50 2.51 7.15 0.24 2.1. 19 Experience proves that spar can be added with the lime, and it can at least be added while the lime is in lumps in the slag without danger that there will not be plenty of time to take care of possible re-sulphuriza- tion. Experience also shows that heats handled with spar are always very low in phosphorus. The writer draws the following conclusions: lf fluorspar is added to an open-hearth slag, it is decomposed and reduced to a certain limit, nam from 2.0 to 2.5 per cent calcium fluoride content. Si is first removed from the slag as silicon fluoride, this silica is replaced by silica from the furnace lining Fluorspar is desuphurizing in its action in that sulp! is volatilized from the slag in some form and the s therefore can take up more sulphur from the bath There was an interesting discussion of this paper which was read before the steel works committee of the German Iron and Steel Institute. One spea mentioned the great danger of using fluorspar becaus' of the deterioration of the furnace walls and port « The first result of the spar additions is to give greater fluidity to the slag, greatly increasing its capab for reaction. The whole melting practice is ther favorably influenced and it may be assumed that increased removal of sulphur is due to this cause. Mr Schleicher disputed rapid deterioration of the furnace ends or walls when fluorspar was used, but admitted that the hearth suffered and the dolomite consump was increased. Another speaker mentioned that fluorspar burst into fine particles when added to the furnace becaus' of its water of crystallization, and had a very harmtu effect on the roof, walls and ends, and on this account was only to be used in the most urgent cases. In rep!) to another speaker, Mr. Schleicher said numerous cas‘ had proved that. after spar additions, the sulphur the slag first dropped considerably, and that the sum of the sulphur in slag and metal showed a loss in tota sulphur, and also a re-sulphurization of the metal the bath. In regard to the destructive effects of fluor- spar, it had not been found that the port ends anc roof suffered, but the ladle linings were very rapi('y eaten away. It should not be used unless needed, pu! there were cases where it provided a means for ducing the sulphur in high sulphur heats.—c. B. W. rch 23, 1922 ‘ack-Cutting Attachment for Heavy Miller \ new rack-cutting attachment designed especially the heavy-duty miller has been brought out by the kford Milling Machine Co., Rockford, Ill. Rigid- a feature emphasized by the makers. \s shown in the illustration, the attachment is ped securely to the face of the column, further ort being given by the overhanging arm support ediately above the attachment spindle, at which the greatest strain is received. This strain is to be entirely overcome by the method of clamping he overhanging arm. The drive is by a shank held he main spindle by the tang and drawback. A wide hardened spur gear on the shank drives a spur keyed to the double-lead worm, the latter being ichment Is Clamped to the Face of the Column, Further support is given by the over hanging arm y steel, supported at both ends and provided two ball end-thrust bearings. The worm drives ’ bronze worm wheel of coarse pitch which has » it, one on either side, two spur gears of wide d with staggered teeth. These spur gears drive ears that are cut solid on the attachment spindle, y close to the front, the other to the rear bear- ‘he wide face gears with staggered teeth are d to assure smooth drive. attachment spindle is of special alloy steel and bronze taper bearings which are provided with for taking up wear through the adjustment of nut. The solid shaft on which the two spur nd worm wheel are mounted extend through tachment to serve as an over-arm support for tter arbor. The worm wheel and spur gears on aft, as well as the gears on the spindle shaft, i bath of oil, an oil cup at the side of the attach- erving as an oil line. rack-indexing attachment used in connection e rack-cutting attachment is fastened to the n the left-hand end of the table and consists racket which carries an indexing and locking ith change gears. It provides for cutting racks aking settings without relying on the usual dial purpose. The various gear combinations per- ks of different pitches to be indexed by making half turn, a complete turn or two complete f the locking disk. Eighteen change gears pro- the cutting of the following diametral pitches: by half pitches; all pitches from 7 to 16; and pitches from 18 to 32. Circular pitches from 16 in., varying by sixteenths of an inch. The se used has jaws 30 in. long and opens 5% in. rack cutting attachment will be made also for 1%4 machine. Tr Keith Car Works, Sagamore, Mass., have re- perations after a shutdown of three weeks. THE IRON AGE 785 National Metal Trades Association to Mcet in New York, April 19 and 20 The 24th annual convention of the National Metal Trades Association will be held at the Hotel Astor, New York, on Wednesday and Thursday, April 19 and 20. On the Monday preceding, the executive commit- tee will be in session and the 23 local branch sec- retaries will hold their semi-annual meeting. On Monday night, the Administrative Council and the local branch presidents and secretaries will meet at dinner. On Tuesday, the administrative council will hold its semi-annual meeting and the local branch secretaries will continue their sessions and at noon the administrative council, local branch presidents and secretaries will meet at luncheon. The annual din- ner of the Alumni Association, consisting of the or- ganization’s past officers, comes on Tuesday evening. The convention will open on Wednesday morning with a short business meeting, followed by a program of unusual interest. Able speakers have been secured to discuss business, financial and labor questions. The association, after a careful survey of apprenticeship training, covering a period of more than two years, has prepared a thorough-going plan of apprenticeship training, which will be submitted to the members at the convention. Angle Fixture with Perforated Plate A universal angle fixture with the plate perforated as shown in the illustration, for insertion of patent clamps, has been placed on the market by E. L. Krag & Co., 50 West Randolph Street, Chicago. The perfo- rations and clamps are intended to facilitate fastening and adjusting the work, the fixture as a whole being designed to permit easy and economical angle set ups on milling machines, surface grinders and drill presses. The plate swings a full 180 deg., or 90 deg. on each side from a horizontal position, and revolves a full 360 deg. on the base. Surfaces of the plate are ground true and square with each other. Both dials at the joints are graduated in degrees and the plate hinged The Perforation of the Plate Is for Insertion of Patent Clamps, as Shown on a %-in. stud which is threaded at one end and is used to clamp the plate in the desired position. The faces of the large flanges on the plate engagi