The Iron Age 1925-12-31: Vol 116 Iss 27

ESTABLISHED 1855 THE IRON AGE New York, December 31, 1925 VOL. 116, No. 27 Charlatans in Iron Metallurgy Modern and Historic Nostrums—Thomas Process Once a Fake—Chlorides and Iodides in Puddling—Patents BY HENRY D. HIBBARD* EFORE chemistry was used to control iron metal- lurgy (used in its broadest sense), and even after it was quite generally so used, but before it so completely dominated the art as now, there came into notice a continuous succession of men who, often un- familiar with the subject, advocated certain methods, procedures or nostrums relating to iron or steel as hav- ing great influence in improving or cheapening the product. The first of these were probably pre-historic. In ancient but historic times they included the advocates of the use of goat’s urine, or the living flesh and blood of a “Nubian of fair form” for quenching heated steel, particularly a sword blade, to give it the proper tem- per. Their number since then has been beyond com- putation. For every good sound practicable idea prob- ably ten worthless ones have been advanced. Some of these men might be classed as charlatans or, to use the more modern term, “fakes;” others were indeed sincere, believing in their ignorance that their claims were founded on truth and fact. But the fakes were knowingly impostors, trusting to their cleverness and verbosity to make some profit out of their worth- less ideas. It is curious and not devoid of interest to note how some of them jumped at conclusions which now seem absurd but for which they had what may have appeared to them sound, or at least plausible, foundations. It therefore excites no wonder that, when a man came along with something truly meritorious but novel, he had a hard time in getting even a hearing because he would naturally be classed with the swarm of im- postors and others who had gone before, some of whom may have been successful enough to have cost the iron trade, or some of its followers, money. The iron- masters who had had that experience could hardly be blamed for refusing to listen to, and much less to carry out, ideas which, judging from previous results, prob- ably called for expense without return. Early Days of the Thomas Process When Sidney G. Thomas, the inventor of the basic process for making steel, announced at a meeting of *Consulting metallurgist, Plainfield, N. J RNDEELeHnennnnnDeLENOREOONCOLAUUORDEDONEDLOONOLOLUENDDRDENEEROOONADOSODODOUSEDNONOH OD URN EO HTOET DUNNE HUONARHONEREHITERNOSESHONOnOnENErDEN® the Iron and Steel Institute in 1878 that he had a process for eliminating phosphorus from iron in the Bessemer converter his remarks were treated almost universally with indifference or derision. When he presented a paper on the subject to that institute in Paris later in the same year, it was not read, though it was printed and circulated. There were a few, however, among those present who saw something in it and we can take satisfaction in the fact that Holley, an American, not only saw merit in Thomas’ ideas but did something toward de- veloping them by recommending them to the attention of G. W. Maynard, another American then in England, who gave them a trial and who has written some ac- count thereof. Indeed, when Maynard told Thomas that he believed he (Thomas) “had it,” meaning the removal of phosphorus from iron in converting it into steel, the latter, with tears in his eyes, said that those were the first encouraging words anyone had given him. Salt in Puddling Iron It had long been known, perhaps from shortly after the time that the method of puddling iron on a basic, that is, an ore lining, was introduced by Rogers early in the past century, that common salt (chloride of sodium) was a beneficial agent in the puddling opera- tion. We know now that its good effect was produced by the sodium and not the chlorine. The salt, or that portion of it which was not im- mediately volatilized by the heat, was changed to oxide of sodium or soda, which combined with silica in the cinder, forming the easily fusible silicate of soda, in- creasing the basicity of the cinder and also its fluidity by lowering its fusion point. The more basic cinder favored the elimination of phosphorus from the iron, while the lower fusion point resulted.in a cleaner sep- aration of the slag from the iron when the bloom was worked by squeezer, hammer or rolls, AS a result of this good effect of salt certain per- sons, thinking evidently that to the chlorine was due the credit of the improvement in the quality of the iron, assumed that, if that element were benc.cial, others of the halogens might be even more so, and cre eenenenennangy, ERE we have the story of some of the “cure-alls,” ancient and modern, for the ills of steel and iron metallurgy, recounted by one qualified to do the telling. Among these, the following take rank as the more prominent: Salt as a benefit to puddled iron. The “Sherman” or iodine process for steel and iron—once seriously dis- cussed by British and French metal- lurgists. Wmovenesveveunvesnnverersaneneeneuncatunveneeoenny Nitrate of soda for puddled iron, and bone black for crucible steel. Patents, good and bad. The story of the Thomas steel process—once pronounced a fake by prominent metallurgists. scusscnananenennnnsanansnseneseuenensnenensesnsewenensnnsstnsnenebretnenenensterneseseOenneesnene”SHRTERSHOSTENONSHETONEESISENEDEERETISIRENISITEEN TREN ETSIRISEDSEINEISTSSRSEIEONNERSSENSENIESSEROSEFIENENETONNTSAOTREREERINTON TNS 1795 inne on png i Eat ie i a ve ms d t | a iy in ia ia ‘Be 1 i } ; 1796 based so-called “processes” thereon. Of the other three halogens, iodine and fluorine have had their advocates who loudly proclaimed them as cure-alls not only for iron but for steel as well. Whether or not anyone ever took up bromine the writer does not know, but it is quite likely that someone did. The “Sherman” or Iodine Process The advocate of iodine was one Sherman, whom I have heard described as a man of good address. He certainly succeeded in attracting attention to his “process,” which consisted merely in throwing a little discolored iodide of potassium into a puddling furnace or Siemens-Martin steel furnace. In a few seconds it f course all went up the stack. It is amusing to read the serious references to the “Sherman Process” in the technical press of 50 years ago and the discussions thereon by such a conservative body as the Iron and Steel Institute. Sherman ob- tained patents for his process and his vogue endured for several years in France, where he had stanch ad- vocates and supporters. In this country the method was tried at the Norway Iron & Steel Works, South Boston, Mass., but of course with negative results. Fluorine in Early Days The use of fluorine was taken up by one Henderson who claimed that it would eliminate phosphorus in large proportions from iron; enough so that any pig would be suitable for making steel. It was before the basic process had been invented and the requirements for dephosphorizing iron were known but dimly by any —by most, not at all. So his plan for doing it was ostensibly as good as or better than any other. He introduced fluorine into the bath, in puddling and open-hearth steel furnaces, in the form of fluoride of calcium (fluorspar). Though his claims were for the most part unfounded, the use of the spar has survived, partly because of some desulphurizing action it has on the metal, but chiefly for the fluidity it imparts to basic slags deficient in acids and hence too infusible and needing a flux. Nitrate of Soda in Puddling In 1869 Heaton proposed and tried to make superior wrought iron from what was then considered inferior pig iron by adding niter (nitrate of sodium) to the charge in the puddling furnace. Whether he based his hopes on the oxygen or the soda in the reagent he did not say. Both were known to play a part in iron metal- lurgy. Some of his results were quite encouraging and point to the soda in making the slag basic as the bene- ficia] ingredient, some phosphorus having left the metal and entered the slag. Half a century ago certain parties advocated the addition of “codorus” or “silicon” ore to the charge in puddling, the only effect of which, as Howe pointed out, was to increase the volume of slag. Holley described it in the following Limerick: There was an old man of Codorus, Who said he’d take out the phosphorus, So the iron he puddled, And with chemicals muddled, But the puddling took out the phosphorus. Bone Black in Crucible Steel Within a few years a New York man has advocated the addition of bone black to the crucible steel charge. He evidently reasoned that, if ground bones were good for carburizing steel by cementation, as in case- hardening or face-hardening armor, they would be good to add in melting. A little knowledge of steel metallurgy would have told him that if phosphate of lime, which forms a large part of bones, were to be melted in a crucible with a steel charge having an acid slag, the phosphorus would all enter the steel and ruin it. The claim that the iron in a certain ore is better than that in some other ore borders on charlatanry and has only in recent years been discontinued. Iron is one element and only one. And there is only one chem- istry of iron as of any other element. Any variation THE IRON AGE December 31, 1925 between two pieces of iron which have had the same treatment is due solely to the non-ferrous ingredients contained. Direct Processes An attractive but probably hopeless field of effort is the production of steel from iron ore by a “direct” process. Many able men from Siemens down have tried it unsuccessfully, foiled usually by the non-fer- rous constituents of the materials they employed. The late James C. Bayles, in considering a direct process 40 years ago, acknowledged what a fine thing a work- able direct process would be; but he added that, under certain conditions, “which might exist in one’s mind, for instance,” a direct process might succeed. But the ores, fuels and fluxes in the earth are as une finds them and are not ideal or suitable for this purpose. With an ample supply of ore containing 99 or even 98 per cent of iron oxide one might succeed with a direct process. Patents Goods and Bad The patent lists show a great number of mixtures for improving or cheapening iron or steel as well as many processes and methods which have never got into use. Some of these were based on sound principles metallurgically, but gained no place for divers reasons. Many could and should have been detected as imprac- ticable, from knowledge of the requirements of success- ful practice. Other things held to be of value in the art were kept as secrets. Some of these patented or secret nostrums aim to improve the quality of cheap, ordinary steels so as to make them as good as the best. Others are for making burnt steel good again. In both cases the betterment is claimed to be accomplished without re-melting, an operation which any well-posted steel worker knows to be indispensable in such cases. . Over 40 years ago the writer was asked to watch and record results from the use of a certain physic in puddling iron, of which the formula was: Lb. Black oxide of manganese............ 6 German plumbago .. i : 10 Sulphate of iron.. Sulphate of zinc ‘ st ; ‘ 6 Sal ammoniac abe ib s-ate : 4 Common salt ‘ 200 OD latin eMac ite ie eit ed & Lae 230 The directions for using it were: “1% lb. to a charge of 500 Ib. of iron. Add after etal is melted and is as hot as possible. Then work with damper down with smoky flame.” This mixture when added made copious fumes but the results from a number of heats were not such as to warrant the continuance of the practice; they were mostly negative. The salt alone would probably have given better results than the whole physic. When something new metallurgically either in ma- terial or method is tried, the furnacemen instinctively feel that it is they and their work which are under trial. Sometimes therefore the new process or Ingre- dient is credited with improvement which is due partly or wholly to better efforts of the workmen. In one experimental charge of puddled iron, which came to my notice, the muck bar obtained weighed con- siderably more than the pig iron charged. After the observers had departed my informant demanded of the puddler how it happened and the latter, with a grin, admitted that he, while poking his fire, had introduced a piece of scrap cast iron weighing about 25 lb. through the fire and over the bridge wall into the charge in the working chamber. He did not want to be blamed for a small yield. Even today the charlatan or dreamer someti.aec gets a hearing. Some iron and steel masters, not feel- ing sure that an amateur or at least one inexperiencea in iron or steel metallurgy may not beat science, a not unknown occurrence, are willing to try an experi- ment that is not manifestly hopeless, if the claimant contributes his time for it without compensation. Testing Metals for Aircraft* New Proposed Standard Specifications and Methods for Testing Light Alloys BY N. ITH the foregoing discussion as a basis, pro- W posed standard specimens and methods of test- ing aircraft metals are offered which, it is believed, will meet the immediate needs of the industry. These are put in specification form for the sake of simplicity and usefulness and, where possible, accepted practice and text have been used. Points of differentia- Ly R=D 1 eS Pa j—__«D_ | :8 7 = 6 > RYE «oe =P ---- ohe-C ooh) a KJ TYPE ] rs . as e eR=D fe | k- Col be--G ---3} Coy Les as K *«----P > K > _TYPE 2 Ls i it L mi iE = < FC P Cup | KA> TYPE 3 All Dimensions in Inches é BIBS cconcceccccccses 1 2 3 4 Size of stock.......... %up *%#to% *to% Mto% A U.S. or 8S. A, EB. threads... % Ys By VW B Shoulder diameter + 2%.. 0.600 0.450 0.290 0.150 i a eee % ly Be % D Gage diameter + 2%..... 0.500 0.375 0.250 0.125 Be as tcvedecesen 1 84 ly & G Gage length + 0.002...... 2.000 1.500 1.000 0.500 & Appramimete vccscess. so %4 ‘s 3 Yy i. SOURED ccc ic ceces 3% 25% 214 144 ee. MEBPOMIMIREO occ ccc scene 6 4% 3 1% Oe! ee 9% 7% 6% 4 Le Approximate ............ 6% 4% 3% 2 P Parallel length .... 6s cess 3 2% 1% y, Plate 1—All Specimens Shall Be Tapered in Diameter Toward the Center of Gage Section by an Amount Not Greater Than 1 Per Cent of Gage Diameter; When Testing Type 2 Specimens, the Ends of Gripping Jaws Shall Not Approach the Gage Portion of Specimen by an Amount Less Than Dimension (C) as Shown tion are noted which will facilitate criticism and aid in any revisions found desirable. General 1.—These specifications shall form part of all indi- vidual specifications except where specific differences occur, in which cases the individual specifications shall govern. Sampling and Chemical Analysis 2.—The manufacturer shall furnish chemical analy- ses of all materials offered where the composition is specified. The methods of analysis shall be those agreed upon between the purchaser and manufacturer. 3.—In general, samples of materials for chemical analysis sha]l be taken as follows: (a) Material 1.5 in. or less in diameter or thick-, ness shall be sampled through or across the entire section. For larger sections the sample shall be taken over an area whose central] axis coincides with a line parallel to the axis of the piece and midway between *Second half of an article published in Tum Iron Aas, Dec. 17, page 1660. The author is engineer of tests at the Naval Aircraft Factory, Philadelphia. S. OTEY its center and surface, simulating the locations shown on Plate 4 In the case of irregular shaped pieces, a composite sample shall be taken from the thickest and thinnest sections. (b) Samples may be mens. (c) Sample be less than 2 oz. unless otherwise agreed upon between manufacturer and pur- chaser. They shall be clean and free from dust, oxide or extraneous matter. All sampling shall be done with slow-speed and surface cuttings shall be discarded. taken from broken test speci- s shall not tools 4.—In case segregation is suspected, a sample from any point may be analyzed. The percentage of any element of this sample shall not deviate by more than 10 per cent of the amount specified. 5.—If unsoundness or piping is suspected, may be nicked and broken and the samples fracture examined. 6.—Materials may be examined microscopically and shall not show sufficient porosity, slag, dirt or other defects to make them undesirable. Preparation of Test Specimens Tensile Specimens: 7.—The axis of test specimens from worked metals such as bars, billets, forgings, etc., shall be located as » , . >! he G > R _ I - ~—v r Ww Ci — x — — = ™ on -~ Md % — =e S > -aTk <D-> Fic.] <--> \. eads of Testing Machine } 1) 8 wws ot lesting Mochine vat Wt ‘) TA ete LL! mh TT | iii”: D - “ D | nn PRM U v4 vo NUS | Sheet Thickness——————. Dimer ; In. and less % to % in. Inel. Gage length . I 4 in 2 in 4 in. » Minimum 7 ! 11.75 in 9.75 in 11.75 in P Minimum . 00 in 5.00 in 3.00 in 5.00 in a | 0.750 in 1.125 in D Minimum ... 0.875 in 1.125 in R Approximate .. 0.6 in. 0.5 in. S Approximate .. 0 in 3.0 in a Suveswnndececas r 0.010 in % in 0.015 In Kk dbsesmenictuene Thickness of Sheet Plate 2—Specimens Shall Be Reduced in Width (W) at Center of Gage Length (by Draw-Filing) Not More Than 0.004 Inch When (W) Equals % inch and 0.006 Inch When (W) Equals % Inch; the Distance (D) Be- tween End of Gripping Jaws and the Shoulder of Specimen Shall Not Be Less Than the Gage Width (W). In testing thin sheet metal the tendency to tear and break near the shoulders can be reduced by making (C) not greater than 1.13 times (W) shown on Plate 4. The transverse axis of specimens from sheets or plates shall be located as near the cen- ter of the sheet or plate as practicable. 8—Round bars under % in. in diameter may be tested without machining. Bars which are not round 1797 1798 December 31, 1925 THE IRON AGE (hexagonal, square, etc.) and are under % in. in thick- men shall be not less than the thickness of sheet or ne Ss may be machined to the largest round possible ate ana tested. In testing specimens of this type the ) Here again the parallel lengths have elongation shall, in all cases, be measured over a gag‘ and limits set for gripping jaws as length equal to 4 times the diameter. The acceptar ted ragraph 9 f data from these tests as representative of th b) M ning the edges of sheared specimens 1s terial shal : tend I ove the material that is severely cold eria all be optional with purchase: . shearing operation Th in s en . « S} te v po! 11. (A)—Specimens shown on Plate 3 shall be Ww po loes istif sing me sed for cast, low shrinkage, non-ferrous metals such show! Plate 1. This pra t ar aluminum, magnesium and their alloys. When ese specimens are not attached to the articles they ' represent, they shall be cast as shown in Fig. 1 of Plate 9 in correspond to those ak n o 60 t the shoulder radius has been r . e tendency to break at this 1_¥ I - en of Plate 3 is preferred to ok > kk m he “zi so Y the difficulty in applying an axial y ' id YPE | piled from these castings have inmachined specimens and, since Cadet Grisn ound ffect lled surface) are considerable, it > 3 7 : : > red advisable to change this practice % 7 ba ~ nwve gation LTA r a - method f casting shown in Fig. 1 of ¢ mended since, in the process of cast- 1 ‘ 1s an opportunity to wash the mold ‘iy 1 er castings. The location of gates, . 4 3 > ] d é s such that shrinkage and temper- TYPE 2 f s are practically the same for each speci- _— Specimens, Typ » ORS Ss : (B)-—Specimens for cast, high shrinkage alloys, Tapered in Diameter From 0.510 In. at ti k shall be cast hown hs 2 o S - nang: Ise . ze te.. s "aS © S Ends of Gage Portion to 0.500 In. at the Ce mal oon e bronze, etc., Shall be Cast as 0 “ ’ ™ ° ’ ‘ ‘ » ( 7 ar ans _ © r ter of Gage Portion: opvecimens to Be ( as . I late J and machined to dimen ions shown Above Dimensions and Tested Without M 1 or 3 specimens of Plate 1. chining spe s and methods of casting 9.—Standard specimens from bars, billets, for 5 ciety etc., shall conform to dimensions shown on Platé x4 ; ty! form indicated by types 1, 2 or being opt wit { had the manufacturer except for hard « ren es » which cases either type 1 or 3 shall be Si Fig. T pec dev S.A Federal standards ir I Greater latitude is ittaching spe £ t é 0/4 x gine 3 ‘ i /4 \\ if , = 4x 2 gt! i t T . D;, sé ara etl \ ae . ‘ agee a | é ) I diffs Dp 1 ide ¢ » n = . ‘ Plate 4—In This, Fig. 1 Applies to Bars 1% In. : and Less in Diameter or Thickness. Fig. 2 Ap- . plies to Bars Greater Than 1% In. in Diameter . or Thickness. Axes x—vzx' Are Parallel to the neni Direction of Rolling ; v ; rd practice and any changes should be . wi a led by ustive investigation. 10.—Specimens from plates, sheets and shapes s] Specimens from tubing shall be prepared for nform to dimensions shown on Plate 2 W here test in f section up to the capacity of the largest have beer it by shearing, the mate ‘ testing machine available. Where the strength of the re ved from each edge ne gage port t full section tube exceeds the capacity of the largest “ 8 * ‘> Sd rds : > 228 1.25 8 45%» = ee ai : 43 Ps acta ; «- 0.80 "> x x je J” oaesa 6--> kp Plate 5—A Represents the 7794 . . a B Charpy and Izod Bar for Tension; B, the Charpy for Transverse; C, the . Izod for Transverse* and 110 S D, Another Izod for K- 0866" 4 Ss S66 > Se ale, ; ae si Transverse Tests —, ™ ~~ ¥ ¥ x » f sae mip \2.394 - 7 x x _ x ay he +-- 3 - = ~ “aA, 9.334 December 31, 1925 Ki? Min -6 Max: >| 8 y* o \R=20, Lae 35D PS 7" f = Plug tobe snug (oe 23 to D,<*-.., At in Tube . roximate £nd shape optional Appro of Normal Gr&D , Heads of sone K { Max purr GrOrl2 ) > Testing Machine Mirnimurn Gt O+4 Machirre sine lea aril, hen Ty he USC Oly W ¢ UY —~>? section exceeds the s “ k -apacity of Jest ng Machine 4 < x J ~~ i Caudben «14 Fraee Tithe ror / % ~—" y We 1orn 7 ( Wy mT 13 be sreater than a wiat? . i 4 Ar! fi - ~ 4 WZ4 Cy 0 4AM! Ty Be cut before flattenin , \ 9 De C ; kD,» and prepared ac y to Plate 2 late 6—Various Types of Tests for Dif ferent Sizes of Tubing testing machine available, specimens shall be prepared as shown in Fig. 3 of Plate 6. Bend Specimens: 13.—Bend specimens from sheets and shapes shal conform to dimensions shown on Plate 8. Their edges may be rounded to the radius shown, in which cases the edges shall be finished by drawfiling parallel to the longitudinal axis of the specimen. Note.—Much controversy has been expressed as to what constitutes a longitudinal or transverse bend The definitions shown on Plate 8 are determined by the direction of the longitudinal axis of the specimer with respect to the direction of rolling or working of the sheet in process of manufacture 14. (A)—Crushing or flattening specimens fo! tubes, used to disclose seams or flaws, shall be of the full cross-section of the material and shall have a length equal to 1.5 times the nominal outside diameter +0.015 in. Their ends shall be machined normal to the longitudinal axis of the tube. 14. (B)—Crushing specimens for tubes, used for strength tests, shall be of the full section of the ma- terial and shall have a length equal to 15 times the nominal wall thickness. Their ends shall be machined normal to the longitudinal axis of the tube. Impact Specimens: 15.—Impact specimens shall conform to dimension shown on Plate 5. The faces of rectangular specimens shall be plane and parallel. The base of the notch must be of uniform depth and normal to the longi- tudinal axis of the specimen. Notches may be milled or ground but shall be finished by lapping. Note.—(a) The impact tensile specimen shown on Plate 5 has been made geometrically similar to those of Plate 1 and of such a size that for most material rupture can be produced in an impact machine of 120 ft.-lb. capacity. (b) The impact bend specimens are fairly well standardized but the type of notch used varies con- siderably. In order to establish some basis for com- parison between the Izod and Charpy tests, the notches have here been made the same. Physical Properties and Tests Testing Machines: 16.—Testing machines shall be in good working condition, and calibration evidence shall be furnished as to their accuracy and sensitivity. Tension and com- pression machines shall be accurate within +0.30 per cent of any registered load and shall be sensitive to 0.01 per cent of their maximum capacity when fully loaded. THE IRON AGE 1799 Note.—(a) The above accuracy requirements should apply only over a range of loading for which a par ticular machine is adaptable. A recommended range is betwee the limits of 5 per cent of the maximum id 100 per cent of the maximum capacity For example, a machine of 100,000 Ib capacity would be required to have an accuracy within + 0.30 per cent of any registered load over a load range of 5000 to 100,000 lb Such a machine would not be con sidered suitable for loads below 5000 Ib. unless the loads were applied very slowly and extreme care tak: in Maintaining beam balance (b) The sensitivity Capacity ar value given would require that the beam of a 100,000 Ib. capacity machine show per ceptible movement if a weight of 10 lb. were placed n the weighing table with machine under full load Test Grips for Tensile Tests: 17.—The grips used for tensile tests shall provide axial alinement and even gripping of specimen. Tubing Tests: 18.—Tubing shall be tested in full section up to the capacity of the largest testing machine available. Where tubing is tested in full section, the plugs shown in Fig. 1 and the “Set-up” shown in Fig. 2 of Plate 6 shall be used. Tubing that exceeds the capacity of the largest testing machine available sh&ll be prepared as shown in Fig. 3 of Plate 6 and tested in the same man- er aS specimens from sheet metals Note he writer t aware of any standard g tubing Although mportance, the engineering iz On Pla i lardiz i x i epted Stress (P/SI): 19.—The term stres ised in these specifications hall be interpreted as the load in pounds divided by the original cross sectional area in square inches It may be indicated by the abbreviation P/SI Proportional Limit (P.L.-P/S1): 20.—The proportional limit is the stress at which deformation ceases to be directly proportional to the load. It shall be determined from a _ stress/strain (load/deformation) curve as the first prominent point f inflection in the curve. The deformation readings for plotting this curve shall be taken with an exten someter which will measure 0.0001 in. unit deforma- Jo-A A B vae-B ~ + ¥ , 4 43. 4 6s a a” haat é “a. lg a » 7 4 4 be Je -B Z , y "9 Plate 7—Stagger Method for Laying Out Gage Marks in Determining Elongation tion of the specimen. The extensometer shall be at- tached to the specimen at the gage points. Note The reader is referred to the annual report of A.S.T.M., Committee E-1, 1925, for a broader re- view and suggestions of methods for making this deter- mination Yield Point (Y.P.-P/SI): 21.—The yield point is the stress at which marked increase in the deformation of the specimen occurs without marked increase in load. For determining the yield point one observer, with a pair of dividers, watches for visible elongation between gage marks on the specimen. When visible elongation is observed, it is reported to the machine operator who records the load at that instant as indicating the yield point.. An a i : ed a 7. % ‘ ee 1800 THE Plate 8—When the Direc- tion of Rolling or Draw- ing Is Along the (x — =x’) x Awis of the Bend Speci- men the Test Shall Be - Called Longitudinal Bend ing. When the directior of rolling or drawing along the (y YyY) axis the bend specimen the test Mi shall be called transve? nal thickn bending Where — stock is less than 6 1% neth (L) = n width, the length of 6) Spe cimens for transverse bending shall be equal to the width of the strip strip ngation not greater than 0.01 ir er a 2-in. gage length shall be considered visible In case an exten someter is used for proof rmation give! by the formula shall be ndicating th yield point. test, a l regarded I E Where « unit deforma 5 specified yield str: P/S!I E = modulus of ela ty, P/SI Ultimate Tensile SI): 22.—The ultimate tensile stress is stress required in breaking a by beam readings on the testing Stress (UIt. T.-P maximun indicated the specimen, as machine. , % YY \ rm — p ry rT CxT) —— x y “ + ~/* x) P ~ 7 ry f > 4 i. A«z t . | | 7 P > - a “4 4 »eé tix ? r a* =a== pope. ---:-1 | A<! 7 J > — PT 4 - * a 7 - >, gis a a - y ; ~ . i. INS: be a < 4 ty os . , A-A / e 9—Met} jd oy Test Dimensions for mac ng are give? ” Plate 1 Elongation ° 23.—The elongation is the percentage difference in length between gage marks before being subjected to any stress and after rupture. The stagger method shown on Plate 7 shall be used for laying out gage marks. Note This is intended 1 ia oO 1 i ng elongation over that portior I Ss] which has undergone greatest leformatior This method of gage marking has beer sed at tl Naval Aircraft Factory for more than three ars with satis faction No mathematica rrrectior re ap] determinations. Reduction of Area: 24.—The reduction of area is the percentage dif- ference between the area of the gage section before being subjected to any stress and after rupture. The IRON AGE December 31, 1925 "| R * Ww x . » TK 4 + ! * e- 4 T) latter area all be measured at the point of greatest reduction. Crush Test 25.—Crushing tests shall be made with a load ap- plied gradually. The load shall be axial and may be applied with a testing machine, having auxiliary bear- ing blocks with spherical seat. Bend Tests: 26.—Bend tests shall be made by means of a bend- ng machine or forming jig. They shall be made in such a way as to insure free bending of the specimen and hammering over the radius shall not be permitted. Surfaces may be lubricated if desired. e such as shown on Plate Note \ for testing duralumin bending machir f 1 satisfactory Hardness Tests: 27.—The methods described in A. S. T. M. reports of Committee E-1 on methods of testing, presented at the annual meetings June, 1924, and June, 1925, shall be used for Brinell hardness testing where diameter of ball impression, under standard load, is measured. Where applicable the Rockwell hardness test is recom- mended. In testing thin sheet metals for hardness by means of a scleroscope, the specimen shall be backed by an auxiliary anvil of the same material as that of the specimen. This anvil shall be at least 0.125 in. thick. hoped that these proposed standards will discussion from those interested in this work, as considerable advantage will be gained if standards can be established on a fundamental basis before the art has developed to an extent where prac- tice and custom have a major influence. Credit is due the Bausch Machine Tool Co. for design of bending machine shown in Plate 10. Acknowledgment is made to the manager of the Naval Aircraft Factory for en- couraging this work and its publication. Very helpful suggestions and criticisms are acknowledged from members of the Bureau of Standards, Army Air Ser- vice, Aluminum Co. of America, Bell Telephone Labora- tories, Inc., and others interested in this work. It is stimulate | | 9 we SZ i f 2h - a) | 1 re al aD A => x eel h MI i 1 Michaela ) oy St Teer Plate 10—Design for Bending Machine. The specimen S is bent with the lever L which swivels about point C, carrying roller R. Pins A and rollers R are furnished in various diameters to suit thickness of specimens Chromium-Nickel Electric Ingots Manufacture in Basic-Lined Arc Furnaces—Preparation of Molten Metal—Thermal Efficiency— Essentials to Soundness HE rapid increase in the amount of carbon and alloy steels produced in basic-lined electric arc furnaces has resulted in the ability of a basic hearth not only to remove phosphorus and sulphur but especially to eliminate or at least minimize the pres- ence of non-metallic inclosures, oxides and dissolved or occluded gases (N:, CO, O:, H,, etc.) more completely than in any other melting or refining furnace. Thus the inherent adaptability of the modern electro- metallurgical processes assures, in this way, a sounder steel for forging or rolling purposes than can be pro- duced in the older furnaces. In the operation of an electric steel plant, however, methods should be used which will result in a thorough Hours knowledge of all the factors which may improve the quality of the produced steel. The determination of the influence of the many governing factors on the chemical and mechanical properties as well as on the uniformity of the product may be most conveniently ascertained by making empirical logs of various heats and instantaneous chemical or heat balance sheets. When this has been done, a comparison of the obtained results on a uniform commercial basis gives the easiest method for any definite decision or useful change in the previous practice. In this paper an effort has been made to show by one of these complete records and balance sheets a sat- isfactory practice in the manufacture of high-grade nickel-chromium steel for an approximate 5 tons weight of ingot. Preparation of the Molten Metal The following outline designates the characteristics of the furnace used, the operation of the heat and the amount of materials added and produced: Furnace : 7-ton Héroult are furnace. Arc : 3 carbon electrodes 16 in. in diameter. Hearth magnesite of an analysis averaging as follows: Per Cent Per Cent Nos oP ih ahd ie ws aaa 1.18 Ca O.. 2.26 BWWAE cane cecasdvsn 5.44 EP <cida ome $9.12 BO a +cetenvncar 0.60 ee SON ns 9.2 ginie.6' 1.33 Specification to which the metal is to be made: *Metallurgist, Works, Chicago. International Harvester Co., McCormick tribution of Heat Supplied by Ele Ma in Electric Furnace Fig. 2 Heat per Nickel - Steel in Basic Elec- - HRUSKA rer Ue Carbon 10—0.4 Sulphur Manganes¢ ).50 Nickel .... Silicon ... 0.1 Chromiun Phosphorus 015 max Charge used in making the heat: Turnings ee ees Scrap (aver. 2.62 per cent Ni) Ferronickel (2 i per cent Ni) Nickel (96.7 per cent N Metal Fig. 1 (Left)—Dis- the ctric Current in king Alloy Steel a 7-Ton Héroult (Right)— Distribution One Ton of Chromium tric Furnace Record of the heat: Time 7 48 ~ wre st —_ te 2.32 1801 Per Cent 0.010 max. Length of Operation Operation Charging Current on 32 min. Electrode No. 2 broke; replaced Current on 94 Ib. lime added No. 1 samples of steel and slag taken : Furnace tilted to skim off the oxidiz- Melting: ing slag 4 hr. 20 min, Current off and remaining slag re- removed Slagging finished; current on Slagging : After slagging added: 32 Ib. thas 15 lb. fluorspar 140 lb. carburite 3 min. later. 35 Ib. ferrosilicon 40 Ib. ferrosilicomanganese 55 Ib. lime 38 Ib. lime added 5 shovels powdered ferrosilicon over slag mixture No. 2 samples taken, after the bath was thoroughly stirred 4 shovels powdered ferrosilicon thrown on slag No. 3 samples taken 30 Ib. lime added 3 shovels powdered ferrosilicon No. 4 samples taken No. 5 samples taken Added : 172 lb. ferrochromium 60 Ib. lime 4 shovels powdered ferrosilicon 4 shovels powdered coke No. 6 samples taken; added 25 Ib. ferrosilicon 7 Ib. ferrosilicomanganese then stirred very intensely No. 7 samples taken, after the heat at Aest Dee eseenegnaantncees te ses ee encene vs. (Continued on page 1845) + Nanmanuanpeness ese ELD OREOET eee HOTA i w 5 @ 8 s + = % 2 4 — OP AIA tm DR i CE BIE R.A IN CNS Machine Tool Industry Thriving While There Is Ample Plant Capacity to Turn Out Orders, Shortage of Skilled Labor Is Being Felt—Some Rising Tendency in Wages Noticed HAT the country is in a real state of prosperity, even tinged in some particulars with a boom com- plexion, was the general opinion of machine tool build- ers who attended recent regional meetings of the Na- tional Machine Tool Builders’ Association. One of these meetings was held at the Hartford Club, Hartford, Conn., Dec. 8, and the other at the Chamber of Com- Rochester, N. Y., Dec. 11. H. M. Cleveland, president, merce, Lucas, of presided at both meetings. rhe association reports that “our industry has about U as much business as we can reasonably expect at this time. While the industry has ample plant capacit: there is not an ample supply of skilled labor to tun out the orders as fast as they have been coming We seem to be witnessing the fi stages of a boor condition with delayed deliveries. The labor factor today actua ly limiting the production of machine too Some rising tendency in wages is also manifest du to this condition. There is an increased cost du breaking in new men, but until now there is no e dence of a material let-down in efficiency of the me employed.” It was the opinior of those who attended the meetings that, from the machine tool manufacturer viewpoint, the situation deserves careful watching that policies may be readjusted to developments ase ders should show a slackening. To Chart Sources of Orders \t these meetings was brought out that machine port each tool industry could profit by a statistica month of the sources developing It was great value if, from which ord explained that this for example, orders from the automobil: should fall off while orders from other indus groups The helpful to every sales manager in where selling efforts could be put fort tage 4 number of the sented at the meetings indiaated they would be industry trial were increasing. information tl gathered would be deciding ie es aqaval companies repre wouid jon ll forms are sent o report as soon as tne l Depreciation for Cost Accounting The question of depreciation for cost accounting purposes was discussed at length. It was brought out that inventory quite naturally, over a relatively short ime, Say one year, reflects changing costs of labor and material due to changing purchasing power of money As mechanical equipment is replaced with more moder equipment, the replacement is reflected ir the balance sheets, but this would take about ten years before all depreciation is taken from replacement cost machines. In the meanwhile the depreciat the dollar would not be reflected in the depre discount. In the case of buildings where the ment is so much slower, the executive is still deceived as actual depreciation if the do not reflect depreciation from rather than depreciation from cost of acquisition. Even in the case of land values that have great) appreciated due to inflation of currency from pre-wa) periods, the true earning power of the company is not properly reflected if this appreciated value is not set down. The stockholders had originally invested a give: amount of purchasing power, and if earnings are merel;: fi dollars which truly represented that new cost ol on new repiact | more cost account replacement cost figured on the purchasing power at one time, but do not represent it now, the executive has not the actual facts before him when he goes to make his price. It was pointed out that if a machine tool company found it necessary to move out of its present quarters, and either buy or build a new plant, the actual value of the new plant in inflated currency would be imme- diately reflected on its books. But the old plant as a social economic unit is worth in production its depre- ciated value measured in present day dollars. This principle of valuation, it was stated, is well established in the one case of public service utilities and railroads, the courts having decided in numerous cases that the itilities are entitled to earn a fair return on present day values. It was contended that if this is fair for utilities the same principle of equity should apply to any manufacturing business. Life and Utility of Machinery \ pra al point as to life and utility of machinery vas brought out. Taking ten years as a fair estimate the economic life of the equipment in a machine hop, the average age of the equipment should It was held erefore approximate about five years. .e valuable information for the executive to have equipment listed by his accountants, hat a definite calculation of average can be made. If he finds that his equipment averages longer than five ears of age, he knows that it is getting obsolete ister than it should. Then if he also finds that his quid funds are not sufficient to replace enough of equipment to bring the total to an average of five ars, he is faced with something that he should in- estigate as to his company’s policy. The opinion was given that the form of invoice ibmitted the Ford Motor Co. has advantages over the form of the National Association of Purchasing Ager Although the machine tool association has read ndorsed the form of the purchasing agents’ ganization, it was the opinion of members attending the regional meetings that the Ford form is the better standard and should be recommended for general aoption Certain instances of alleged unfair German com- cited. The association will deal with h complaints through its office in Cincinnati and as may seem desirable. Regional meetings are scheduled to be held at ve land and Ros kford, Til. @PTITIO? were ich action Cin- nnati. Cle Radial Nut Setter and Stud Driver A radial stud driving and nut setting machine for the rapid driving of the numerous studs, nuts, cap screws, etc., used in automobile engine, chassis and sim- ar assemblies has been brought out by the Hammond Mfg. Co., 7808 Kinsman Road, Cleveland. In addition to high production, the driving of the studs and setting f the nuts uniformly to any desired degree of tight- ness is claimed. From the accompanying illustration it will be noted iat the hinged arm feature of the company’s radial drilling and tapping machine is incorporated, which feature stressed as permitting the operator to move he spindle from one position ‘to another with a single traight line motion. The arms are arranged to swing m radial ball bearings. The machine is motor driven, the motor being mounted in a vertical position on the outer arm and belted directly to the spindle driving ulley, as shown. A ball bearing idler for maintaining the proper belt tension is provided and there is a gear reduction of approximately 2% to 1 between the driv- ing pulley and the spindle. The capacity of the ma- chine is for studs up to 5% in. in diameter and for nuts up to 5 in. Dp Two types of the machine, column or wall type, are available, the column type radial being equipped either with a full-size T-slotted base or with a pedestal base. The wall or post type machine has the arm assembly mounted on a slide or shoe and has the same vertical adjustment as the column type. 1802 December 31, 1925 In operating the machine, a nut is inserted in a spe- cial socket wrench in the spindle and the spindle started by pressing down on the operating lever, after which the nut is brought down on the stud. When the nut is tight the spindle stops automatically, due to the open- ing of the driving clutch in the spindle driving pulley. The operator then raises the spindle, inserts another nut and repeats the operation. It is stated that the average time consumed is approximately 5 sec. and that the nuts need no further tightening. The same method is followed in driving cap screws, spark plugs, Either Column or Wall or Post Type Machines Are Available. The average time consumed in setting nuts is 5 sec. and nuts are said to require no further tightening etc. By reversing the motor, nuts or cap screws previ- ously tightened may be removed. For driving nuts to uniform predetermined depth a geared head without the releasing clutch feature is rec- ommended, and also a standard stud driving chuck hay ing split half nuts that release when the stud has been driven to the depth required. A solid threaded chuck is used in connection with the releasing driving clutch. When the stud is driven tight the clutch disengages and the spindle stops. The motor is then reversed and the chuck is backed out. Standard equipment includes a General Electric 1-hp., 1800-r.p.m., ball bearing induction motor, with inclosed starting switch and with drum type reversing switch where required. A box type work table 22 in. high and with a top working surface of 20 in. by 30 in. may be furnished as an extra. The distance from the spindle to the face of the column is 4 ft. 4 in. maxi- mum and 18 in. minimum. The vertical adjustment of the saddle on the column is 24 in., and the traverse of the spindle is 8 in. The weight of the column type machine with T-slotted base and motor is 2500 lb. Machine for Sharpening Hobs and Other Tools A hob grinding machine with vacuum dust remover, built by the Herman Pfauter Works, Chemnitz, Ger- many, is being placed on the American market by O. Zernickow Co., 15 Park Row, New York. The machine, here illustrated, is designated as the model FSS. It is intended for use in sharpening spiral and straight fluted hobs, reamers, cutters, taps, etc., and with a special fixture it is said to be adapted for grinding face mills up to 13% in. in diameter. A ver- tically adjustable rest is provided at one end of the grinding wheel head in order that the machine may be utilized also for the grinding of milling cutters, drills and other small tools, an independent grinding wheel being employed for this work. Operation is semi-automatic, the table having full automatic longitudinal feed, while the setting of the THE IRON AGE 1803 work to the grinding wheel and the indexing from one flute to another is done by hand. With the traverse and return of the table, the work is rotated simul- taneously according to the spiral of the flutes, this being accomplished through a change gear arrange- ment located at the index head. Change gears for different spirals are furnished and also tables for selecting the proper combinations. The table reversing mechanism is claimed to be free from detrimental shock. The grinding operation takes place both during the advance and the return of the table. A feature of the machine is the vacuum dust remover which exhausts the dust during the grinding operation and deposits it in a water tank at the base of the pedestal. Single-pulley drive is provided, the machine being driven by belt from the lineshaft, or by direct-connected motor arranged as shown in the illustration. The table may be swiveled 45 deg. in either direction. The grinding spindle is hardened and ground and runs in long adjustable phosphor-bronze bearings. At the side of the machine equipped with the plain grinding rest, the pindle carries interchangeable grinding wheel arbors with taper shaft. An adjustable wheel-truing device is provided, but the diamond used in this device is not included in the accessories. All machine elements are adequately protected from abra ive dust. The longitudinal feed of table, automatic, is 17% in., the cross adjustment 6 in., and the vertical adjust ment 9 in. The maximum distance from the cente1 f the grinding spindle to the face of the table is 16% °c ——— Hobs, Reamers and Taps May Be Ground at One Side of the Machine and Milling Cutters, Etc., at the Other. The vacuum duat remover ia a feature in. The maximum distance between centers is 21% in., and the maximum grinding diameter between center is 12% in. The size of the table is 7% in. by 45% in. The largest grinding wheel employed is 7% in., and a 3-hp. otor is recommended. The floor space occupied is 67 m. by 71 in., and the net weight of the machine is approximately 2270 lb. Production of bituminous coal in the week ended Dec. 19 is given by the United States Bureau of Mines as 12,600,000 net tons, compared with 12,914,000 tons in the preceding week and 12,868,000 tons in the week before that. These three weeks, at 38,392,000 tons, make the highest total for any period of equal length in recent years. acral Ta ai rmimcvee 2. : i 3 : t i & 1804 Pipe Threading and Cutting Machine With Range from 2% to 8 In. The Landis Machine Co.. Waynesboro, Pa., add- ing to its line an 8-in. pipe threading and cutting ma- chine, which has a range from 2% in. to 8 in., inclu sive. Two die heads are employed, one 4-in. head pipe from 2% in. to 4 in., inclusive, and an 8-in. head for a pipe from 4 in. to 8 in. The entire range of eac} ead is vered by one set of chas¢ The travel of the car ge of the machine is 24% A fu view of the machine « julppead W th gear b and arranged for single-pulley drive shown With, the ay plicati n of the motor drive to the sam nachine being shown in the insert. he gear box i cated beneath the main spindle and provides eigh Variations in speed. All gears are ol teel, have cut eth, and run in an oil bath. The shaft bearings are lubricated automotically by a forced i feed ig lubricated by flat link chains run- reservoirs, vstem, the main bearin ngs beir no n oil The front and rear gripping chucks have universal and self-centering to the pipe. The rear chuck is equipped with flange grips for screwing flanges on and off. Both chucks have three jaws. A feature stressed as exclusive is the reverse drive, which is located in the gear box and is used for putting o1 and taking off flanges, the reverse being controlled by a conveniently located lever. The cross rail supports the die head and is fitted at the rear with centering jaws, cutting-off tools, reaming tool and length gage. The company’s stationary die head and “long life” chasers are employed. The die lubricating system in cludes a rotary pump, a by-pass for the surplus oil and a special control valve at the head and at the cutting off tools. When arranged for motor drive, adjustment are which can be ap Improves Hydraulic Broaching Machine Added weight, both in the base and trough, and greater capacity, are among the improvements incor- porated in a new No. 3 broaching machine being placed on the market by the Oilgear Co., Milwaukee. The pump or power unit which operates the ma- chine has been improved to give a maximum pulling capacity of 25,700 lb. The speed of both the broaching and return strokes may be varied fro