The Iron Age 1920-10-14: Vol 106 Iss 16

ESTABLISHED 1855 pny YW Yi a? ——BY HENRY N the metallographic examination of any metallic | material, a study of the macrostructure occu- pies a prominent and important place. It is generally necessary to use special reagents for re- vealing the different structural features and many such etching solutions have been described and their use is now a routine matter in most metallographic laboratories. One of the most widely used reagents for revealing the macrostructure of copper alloys, particularly the brasses and bronzes, is ammonium a and b—Two welds etched with ec and d—Same welds, @ a) ‘ and eame welds etched with an Fig. 1 agents rsulphate. en This has also been suggested as a ms for re iegh not on the microstructure of iron’ antages ae to any appreciable extent but the m for » Of its use as a macroscopic etching me- ‘ron and steel appears to have been very ureau of Standards, Department of Com- Printed by permission of the director of Principles of and ling Processes ; No. Etching Phenomena Stahl und Eisen: 35, \nalytical Chemistry, vol. II, p. 595. an aqueous solution of coppel etched with 2 aqueous solution (approximately : Macroscopic Structure of Fusion Welds (oxy-acetylene process) © characteristi¢ crystalline condition is revealed best by the 965 > GE VOL 106: No. 16 Revealing’ Macrostructure of Iron and Steel Hitherto Overlooked Use of Ammonium phate—Particularly Valuable for Indicating Crys- talline Condition, and Easy and Cleanly to Apply Persul- S. RAWDON largely overlooked. In the following discussion the use of ammonium persulphate for this purpose and the structural features which it reveals in a partic- ularly striking manner are pointed out. Method of Etching 1. Principles underlying the action.—Am- monium persulphate a very strong oxidizing agent and decomposes readily when dissolved in water. According to Treadwell’, the fundamental is ammonium chloride (Heyn's reagent) per cent alcoholic nitric acid 1 per cent) of ammonium persulphate Reve reagent aled by Various Etching Re Photographs actual size persul phate reaction which occurs when water is added to any persulphate is represented by the following equa- tion :-— (1) 2(NH,)S,0O, 2H.SO, + O,. A further reaction occurs with ammonium per- sulphate by which some of the ammonia is oxidized to the form of nitrate. (2) 8(NH,).S,O, 9H.SO, + 2HNO.,. 2H.O 2 (NH,) SO, + + 6H,O0 = 7(NH,) SO, + The foregoing equations indicate that the general effect of ammonium persulphate as an etching me- dium is that of a dilute acid, the action of which is intensified by the presence of free oxygen. Ina previous article‘ the importance of available oxygen in metallographic etching reagents has been pointed out. It may be easily shown also that aqueous so- lutions of ammonium sulphate have a considerable etching action upon segregated steels, hence it is very probable that the sulphate which is formed as one of the reaction products aids somewhat in the etching action of the persulphate solution. 2. Method of Application. On account of the readiness with which ammonium persulphate crys- tals decompose when water is added to them, the etching solution must always be freshly prepared just before use. One gram of the salt in 10 cu.cm. of water was found to give excellent results. If desired, the amount of persulphate may be in creased considerably, for instance, to 2 g in 10 cm of water. The salt dissolves gradually in the water hence the exact concentration of the etching solu- tion cannot be stated. The etching is best carried out by means of a cotton swab which has been soaked in the solution. The swab is rubbed over the face of the specimen, considerable pressure being used. A fire polish of the specimen is unnecessary; usually it is sufficient to finish the face on fine emery paper, for instance, 00 French emery paper. The dark oxide fiim which often forms on the freshly etched face of the speci- men if it is allowed to stand in the air without dry- Fig. 2—The Mac roscopic Structure of Wrought Iron ing for a few minutes can be easily removed by -a fresh application of the etching solution on the cot- ton swab. An etching period of from one to two minutes is usually sufficient. One of the advantages of the method of etching described is the readiness of control of the process. The surface is constantly under observation and the etching can be stopped at any instant when the structure is distinctly revealed, by holding the specimen in a running stream of water. The photographing of the etched surface of the specimen is best carried out while the specimen is immersed in water, alcohol, or light oil. In case the specimen is too large for immersion, the surface may be rubbed with oil or glycerine in order to increase the brilliancy of the etch-pattern. In gen- eral, this device is helpful in the photographing of all macroscopic specimens, etched by any reagent whatever. Typical Results In the following figures a few illustrations, chosen from a considerable number of specimens etched by this method are given to show the results obtained by the use of the reagent. They also illus- trate the fact that in some cases, features are revealed by the persulphate, which would be missed entirely if sole dependence were placed upon some other reagent. 1. Crystalline heterogeneity. Ammonium per- Rawdon and Marjorie G *Henry S. }'apers n pres Lorentz; B. S. Sci THE IRON AGE’ as Revealed by October 14, 1929 Fig. 3—Macrostructure of Wrought Iron R monium Persulphaie Same specime: t graph of Fig 2 at three times characteristic crvyst magnific lime sulphate is most admirable for revealing « il] heterogeneity of any material. This is illustrat by Fig. 1, which shows sections of two f welds made by the oxyacetylene process. Et with an aqueous solution of copper amm chloride and with alcoholic nitric acid, both f reveal clearly the pronounced grain growth whic! accompanied the welding process and which influ ences to a very marked degree the mechanical pro; erties of the weld. This is very clearly revealed by the us2 of the persulphate. A single type of etch- conditions—-Left 2 per alcoholic aqueous solution (approxi per cent) of ammor etching ; cent phate; aqueous solutio ammonium chloride ( He agent); cupric reagent (Stead’s re- agent for revealing Spno! banding) ; deep etching (2! hot concentrated Various Etching Revge ing reagent should not be depended upon pletely revealing the macrostructure of any spe men. Each reagent used, as illustrated in Fig reveals certain characteristic features of the mate rial under observation. It appears, however, tha the persulphate solution revealed more features a single etching than did either of the other tw In Fig. 2, a specimen of commercial ea iron is shown and the results obtained by the o of ammonium persulphate may be compared with those cf four other reagents in common Use. Al- though ‘he characteristic “streaky” condition roe vealed by several, the peculiar variations in te crystalline condition are revealed only by the per sulphate. ; In Fig. 3, the same specimen 1s shown al 4 Same specimen ena hydro ammo- with hot solution of nium persulphate chlor Aqueous > Sooregated Steel Fig. 4—Macrostructure of Segrese' \ Enlarged Different Etching Methods October 14, 1920 slightly higher magnification in order to reveal the crystalline pattern more plainly. The material, when treated with the persulphate, has the appear- ance of being deeply etched. This is not so how- a—Sulphur print s pecimen, te Olsned and etched with cop- per ammonium chloride (Heyn's reagent) Fig. 5—Segregation in steel rails r, as the etch pattern can be readily removed ing the surface with emery flour. fig. 2, represents the order in which the suc- ive etchings of the specimen were carried out. in each case the prev.ous etch-pattern was removed rubbing the surface with emery flour on the { the finger. It may be noted in passing, that is an excellent method for freeing the surface MCN TPo..e ase gua “pana. has sawe grease before etching the material. «. Chemical inhomogeneity. One of the most ‘ul purposes served by macroscopic etching is revealing of chemical inhomogeneity, that is, is in chemical composition due to segre- cementation and similar causes. Figs. 4 . ) illustrate the fact that etching with persul- © ls usually sufficient to reveal such differences on er chemical analysis of the segregated speci- in Fig. 4 showed that the central and aoe ns of the bar differed principally in the _»/ur and phosphorus content. The percentages OWS ; phosphorus, outside 0.076 per cent, 158 per cent; sulphur, outside 0.029 per _s center, 0.064 per cent. The appearance of , , iace after deep-etching in hot concentrated moni, te acid and that after etching with am- y.| persulphate are quite similar. cee iows a section of the head of a segre- ee Which failed in service. The use of sev- The ... » Common etching reagents is illustrated. ~ Of segregation, which is largely due to wn by Fig. 5a, is quite definitely in- ‘he persulphate etching. ‘OWS a section through a low carbon uLePr. {) ‘Be oO THE IRON AGE 967 steel rivet which holds together two plates of 3% per cent nickel steel. Only by etching with ammonium persulphate was it found possible to reveal any of the “flow lines” within the rivet. b Specimen a was deeply etched with hot concen trated hydrochloric acid, surface was then inked with printer's ink and a “print” mads d Same specimen, re,oQushed, etched with amrm nium persulphat revealed by different methods These are faintly shown in the figure. Other macroscopic etching methods showed only a differ- ence in shade of the rivet as compared with the plates, indicating thus that the two differed very considerably in composition. Variations in structural condition due to local heating of parts of a steel specimen which may arise in such processes as welding, oxyacetylene cutting, etc., are also readily revealed by persul- Fig t Macrostructure of riveted steel plates revealed by ammonium persulphate, actual size The “work lines’ in the interior of the rivet are faintly shown phate etching. Fig. 7 shows sections of the head of a steel rail to which a copper bonding cable has been welded at the side. The depth to which the metal has been affected by the heating is rendered plainly visible by etching with ammonium per- sulphate or with very dilute nitric acid. Discussion and Summary It is evident from the foregoing discussion and aR 968 results that ammonium persulphate is a very useful reagent for revealing the macrostructure of iron and steel. Its action depends primarily upon the formation of acid and the liberation of oxygen from the spontaneous decomposition of the salt upon the addition of water. It is to be recommended par- ticularly for revealing the crystalline condition of a—Cross-section of a steel rail to which a copper bonding wire has been welded, etched with aqueous solution of ammonium persulphate Fig. 7—Effect of Local Over-Heating of Steel Revealed by the weiding torch iron and steel although chemical inhomogeneity is also indicated. It is not to be inferred that the persulphate reagent is the only means by which crystalline heterogeneity may be revealed. Other methods such as deep etching with concentrated acid, or by THE IRON AGE is clearly October l4, 1920 prolonged etching in dilute solutions. f,) picric acid, will often reveal the ga) Such processes, however, are very tedio consuming and the face of the specime) so roughened and pitted as to rende) further value for examination withoy grinding and repolishing the surface. |) it b—Same specimen (not same cross-section) 2 per cent alcoholic nitric acid Different Methods. The depth of penetration of t shown in both cases features close to the surface might be entirely re- moved between successive etchings. The cleanliness of the persulphate reagent and the ease with which it may be applied even to sur- faces of considerable size are also important factors favoring the use of this method of etching. Effect of Zirconium in Cast Iron* Elements Graded As to Oxidation—Effect of Temperatures Results in Steel More Promising BY DR. RICHARD MOLDEN KE = O the list of deoxidizers useful for the purification of cast iron there has been added another ferro- alloy, that of zirconium. As the list of elements ordi- narily in or added to cast iron grows larger a more thorough understanding of the functions of each one of them, particularly those more rarely met with, be- comes of increasing importance. We are all familiar with the action of silicon, carbon, phosphorus, manga- nese and sulphur, but know very little about the special effects of vanadium, titanium, cerium, copper, nickel, chromium, etc. Year by year more of the rare elements come into daily use, and as they become more reasonable in price through quantity production, the iron industry experiences a corresponding expansion into new fields of usefulness. Two Groups of Elements For cast iron the elements involved seem to be divided into two groups. The first is made up of those not readily removed by oxidation in ordinary good foun- dry melting practice. The second consists of the ele- ments readily oxidized under conditions involving the presence of oxygen in the molten metal. The two groups shade into each other to some extent, depending upon the degree of skill possessed by the foundryman in handling his cupola or furnace. The above will be better understood when such ele- ments as sulphur and phosphorus are considered. Both are increased in melting practice by concentration, as they are not oxidized out. Only the action of a basic hearth in open-hearth or electric furnace practice will reduce these elements in quantity, and only through chemical reactions of a more or less complicated nature. On the other hand, it is known that silicon and manga- *From a paper presented at the annual convention of the American Oct. 5. Foundrymen’s Association in Columbus, Ohio, nese undergo definite losses in the melting operation, and mixtures are made up with this situation in view The behavior of carbon and iron itself is less certal Both oxidize under conditions of high heat and the ab- sence of a sufficiency of manganese and silicon to pro- tect them. Most foundrymen have seen the brown smoke emanating from a cupola indicating a low and burned iron, when the silicon of the mixture Was below 1 per cent and manganese nearly all gone. lr air furnace practice the reduction of carbon known, and in long heats there is enough iron oxid the bath to yield defective castings. ed is Ww Grading Elements as to Ease in Oxidizing For the group of the less easily oxidized element cast iron, where melting is carried on under oe 2 possible conditions of air supply to the fue! to prevel” § undue oxidation, the following list may serve It is thought that the order given may be that of the mls stable first and so on to the middle ground. his oa may be phosphorus, sulphur, iron, copper, MICAS" sten, molybdenum and carbon. Then from Cal Ang ready to be oxidized or remain unaffected, deper a upon the care taken in melting in cupola or sega ra order of the elements readily oxidized may De c4'™"" chromium, zirconium, silicon, manganese, V* aluminum, magnesium, titanium and cerium 1e named is probably the one most easily ——_. sie The order above given is practically oa. aioe there is no definite information available on the s°)" The writer has an intuitive feeling that It !s a ele the practical observations made when hang ld he ments in question in their ferroalloys. It - these interesting to subject iron alloyed with ee : elements to a very slow oxidizing atmosphere cet to A the molten state, and make continued anal} ae D0see observe the rate of elimination of oo ai | progressed. This should give the order 0! nine. nadiun removal an¢ October 14, 1920 erence the degree of efficacy for purposes of ation in cast iron. ym the many tests made by the author of deoxi- of cast iron, it seems that the first effect is the of oxygen present in combination with the This eliminates just the amount of the element stion necessary for that laudable purpose. If the Jloy added brings in more than enough for this deoxi- on, the balance of the element remains in the cast ron and exerts its particular function upon the prop- erties of the casting. Thus, the addition of say 0.1 per tanium may remove all the oxygen present in a ladle of molten iron and yield results that are practi- sally as good as if 0.2 per cent titanium had been used. It is the removal of oxygen—the weakening factor in the molten metal—that permits it to come out with its natural strength due to its composition. It seems as if the crystals adhere more firmly and are given the ‘hance they should have for strength due to a good analysis. If these crystals are of finer quality as the result of added nickel or molybdenum, and if the graphite crystals are small and not too large in number, product should be a pretty high class metal. Many ‘aims are made for vanadium and other of the rare elements for cast iron and doubtless there is much to the subject. Fundamentally, however, the less oxygen present in the metal before the ferroalloy addition, the nore characteristic the effect. Hence the soundness of the policy of devoting every attention to good melting practice so that but little of an expensive alloy need be idded to attain a desired effect. Effect of the Temperature One of the difficulties found with the deoxidation of ast iron is the degree of heat involved. It is well known that the hotter the metal the better the effect f manganese added to heats with high steel percent- q ages. Indeed, to get a high steel scrap heat safe for | pouring molds, it is necessary to use a good fuel per- entage. The higher actual temperature of the molten metal resulting promotes the union of oxygen and manganese, and the result is a casting free from blow- noles. With ordinary cast iron the added manganese, nstead of going into the slag, will be found in the metal; possibly partly in combination with sulphur, it having exerted little or no deoxidizing effect. The ‘emperature was not high enough for the reaction. The consequence of the above is that such metals ‘s aluminum, cerium and magnesium are easily taken n molten cast iron, whereas titanium and zirconium more time and heat for the best results. Large Zirconium Percentage Chills Ty — ‘ . ° . ‘n making tests with ferrozirconium, an alloy con- ‘ aining 30.6 per cent zirconium was used. It was “ced that for the smaller percentages the metal nicely in melting and indicated a purifying tor the slag came up and collected for easy val. The larger percentages gave more trouble nilled the metal considerably so that it was diffi- pour successfully. Unquestionably the alloy will T ter service in steel than in cast iron. f sets of transverse tests were made. One with _ “¥ iron mixture and the other with car wheel scrap, ning results for gray and for white iron. Gray Iron Mixture ind gray scrap 40 per cent. Average of three bars each gth Deflection Zirconium Added, in Inches Per Cent 0.10 None 0.11 0.05 0.11 0.10 0.11 0.15 White Iron Mixture els, 60 per cent; white iron scrap, 40 per cent. Average of three bars each 6 strength Deflection Zirconium Added, a in Inches Per Cent 2.64 0.10 None ¥ 0.10 0.05 : 0.11 0.10 ' 0.11 0.15 AS the . ~ . : Neste ‘sual element addition for deoxidation pur- iteoeaas 10 per cent it will be noticed that the strength “is 6 and 9 per cent respectively. Undoubtedly THE IRON AGE 969 where large steel scrap percentages are used, this in- crease will be greater as the oxidation will have been more serious and the temperature of the molten metal higher, making for a better reaction. Further tests in this direction would seem advisable, for the world’s supply of zirconium is quite extensive and it should be converted to the ferroalloy as cheaply as titanium. The above data are given at this time in order that those who are interested may be advised. The tests were made over a year ago. ROLLING MILL THEORY Lack of Knowledge Emphasized in a Paper by Professor Trinks A paper on the theory of rolling, notable for its lucidity, was recently presented by W. Trinks, professor of mechanical engineering Carnegie Institute of Tech- nology, Pittsburgh, before the Engineers’ Society of Western Pennsylvania. Incidentally he emphasized the need for more extended knowledge among rolling mill engineers about the underlying principles of plastic flow. Flow, he pointed out, takes place in the direction of greatest shear. For a given condition of the material the velocity of flow is proportional to the difference between actual shearing stress and yield point shearing stress. That rolling below a certain speed saves in power is well known, the author added, and also that it produces better steel, because the stresses caused by slow deformation of viscous solids are less than those caused by quick deformation. The amount of deforma- tion permissible is unlimited providing the material is always under compression from all sides. Every ma- terial, however, has a critical temperature below which it is hardened by deformation (cold flow) and above which it is not hardened (hot flow). Since most of the rolling mill deformations are by hot flow, the speaker said, there is no limit to the deformation without in- jury to the material if tension be avoided, but tension can hardly ever be avoided in rolling. The effect of tension is measured by the unit of specific elongation which accompanies it. The amount of unit elongation which is allowable in rolling varies with the quality of the material, with the ratio of absolute rolling temperature to absolute melting temperature and with the velocity of elongation. There is a great confusion of ideas, Prof. Trinks asserted, regarding the forces that flow between the steel and the rolls. Most people think, he stated, that the steel is “pulled through the rolls” with great force. As a matter of fact, there is very little if any pulling action. If the speed of the mill changes, as in re- versing mills there is a horizontal force component. There also exists such a component when a piece first enters the mill. While being accelerated a small though negligible horizontal component is present. While it is a comparatively simple matter to deter- mine the direction of the resultant force between the steel and the rolls, it is absolutely impossible to deter- mine the distribution of the force elements of which the resultant force is built up, asserted the author. In by far the greatest number of cases of rolling, there is slippage between the steel and rolls. For that reason, the distribution of forces in the rolling process is quite different from the distribution which establishes itself when steel is compressed between the platens of a press. In attempting to determine the lire of action of the resultant force, Prof. Trinks pointed out, we find how little we really know about the distribution of forces in the mill. This cannot be determined from the work per revolution unless the pure rolling work can be separated from the neck friction work and this to the author’s knowledge has never been experimentally ac- complished. Variable friction also makes predetermi- nation of the work requirements uncertain. While we must admit the present day hopelessness of a mathe- matical theory of plastic deformations, we can do a great deal by careful, analytical reasoning, Prof. Trinks declared. i a tna a al iat ne TIED Press Which Is Inclinable A straight column press which may be used in either an upright or inclined position by simply turning a hand wheel has been designed and built by the Toledo Machine & Tool Co., Toledo, Ohio. It is self contained, being driven by a direct-connected electric motor. Spe- cial attention is called to the motor bracket, which is arranged to keep the motor in a vertical or upright no matter whether the press is upright or position, ol Self-Contained Toledo No. 54A Straight Col- umn Press By turn- ing a hand wheel, the press can be changed from an upright to an sition inclined po The inclined to any angle within its limits. always in mesh. It is pointed out that the uprights is somewhat greater than is ordinarily fur- nished on a press of this size. The slide is of liberal proportions, and is carefully guided in gibs, to insure the accuracy required by manufacturers of electric motors, electrical instruments, etc. The press may be furnished with or without gear- ing, and with or without the bar knockout in the slide and the direct connected lower liftout, as well as with or without the motor bracket. The press is also built with the frame arched out from front to back and with an opening 14 in. wide in each housing to permit of feed- ing the stock from right to left or vice versa. The press as shown in the accompanying illustra- tions weighs about 6500 lb. The principal dimensions are: Area of the bed, front and back, 24 in., and right to left, 23 in.; area of slide, front to back, 21 in., and right to left, 19% in.; opening in bed, 12 x 12 in.; distance between housings, 24 in.; stroke of slide. 2 in.: pinion is distance between the THE IRON AGE October 1920 distance bed to slide, stroke down and ad 13-in.; thickness of bolster plate, 3 in., an f flywheel, 1050 lb. Some of the above di; manufacturer advises can be changed t requirements. Auto Parts Manufacturing Company Formed The W. E. Seymour Mfg. Corporation, M Wis., has been incorporated at $200,000 to mak parts, chiefly piston rings. The executive officer W. E. Seymour, president; J. A. Lee, vice-president general manager; M. L. Buckley, secretary; (. J. G bert, treasurer, and E. E. Hirschhauter, chi: Mr. Seymour has long been identified with mobile industry. He was for six years works m of Fairbanks, Morse & Co., Beloit, Wis., recent}: president and general manager of the A. 0. Smit Corporation, severing his connections to form the pany bearing his name. Mr. Lee has established } self in the automobile industry as productio1 E. E. Hirschhauter was interested in auton neering in France, and has been active in the aut bile engineering of large manufacturers in this « The new company has purchased a manufacturing at Lisbon Avenue and Thirty-first Street, Milwau The buildings are light and airy and include a spa machine shop and foundry. Options on adjoining | erty have been taken. Production will begin the latt part of November or early in December. TT offices are at 266 Plankinton Arcade, Milwauke Sloss- Sheffield : Sis Yard The Sloss-Sheffield Steel & Iron Co., Birmingha: Ala., plans to establish a permanent pig iron yard at Providence, R. I., on the municipal wharf where a stock of foundry iron of at least 5000 tons, various silicon, will be maintained regardless of gen- eral business conditions. The plan has been in process of development since June, since which time considerabl) more than 12,000 tons has been unloaded at that port. Barges were first employed to transport the iron from Southern ports to Providence, but subsequently the steamer Maruba was chartered, which makes two trips per month. The barges operate a week or s0 apart. Steel dumping buckets, with guy rope tilts, are used for unloading at Providence, but the company expects to install at an early date a 52-in. Cutler- Hammer lifting magnet, circular type, for this purpos Improvements will be made at a Southern loading port whereby the cost of handling iron there also will b materially reduced. W. J. Breen & Co., Boston, acts as pig iron representative of the Sloss-Sheffield Stee! & Iron Co. storage Heavy Manganese Imports in August August, this year +h Imports of ferromanganese in were 9804 gross tons, or the largest for any mor this year and for several years. The total to Sept is now 33,515 tons, as compared with 16,994 _ Sept. 1, 1919, or practically double. The exports August were 252 tons, making the total t: 1, { year, 1186 tons, as against 1980 tons to Sept. 1, re Manganese ore imports also made a new recor ) Sept. the year in August at 99,601 gross tons. The t tal for the eight months to Sept. 1 is now 334; 590 tons, 4 against 249,810 tons to Sept. 1, 1919. cniicenliiaiaiadinactaniaeiilais Tin plate is now being transported down odie River from the Pittsburgh district for transs® or to South American countries. The steamer . : Beach brought several hundred tons from Pittsd 4" Cincinnati, where it was loaded on ¢ “ “for - Or'eens, end later transferred to ee for tne mairder of the voyage to San Tauos, Braz! Ride The Iron Trade Products Co., Farmers Bank ©” Pittsburgh, has been appointed exclusive 5 ales Sai oe the coal, furnace and foundry coke output 2!) pronerties formerly belonging to the Westmorel Tr Coal Co., but now belonging to J. L. Kendall. a } a vu DW “ he as Safe Practices in Blast Furnace Operations’ Gas Most Serious Hazard—Need of Care in Use of Helmets—Hot Metal and Cinder Burns—Skip Hoist Cause of Accidents a : BY L. A. TOUZALIN+ the most serious hazard in connection with the operation of iron blast furnaces is the handling ‘ blast furnace gas. While it is true that the improve- nents made in blast furnace construction and opera- yn during the last ten years have largely reduced the .ssity for workmen to come into contact with fur- nace gases, these very improvements, to a certain ex- ent, have made the gases more treacherous and dan- zerous to the operating crew should they come into con- tact with them. In the days of hand filling, the top fillers were apt to consider a gas headache as a normal ‘ondition under which their work was to be done. The nen were brought down from the tops and scattered long the cast house gangs with the replacement of hand filling by the automatic skip hoist. Shortly after this new development, the use of washers for cleaning the gas was inaugurated, and when these same “gas eaters” encountered their old friend in a cold, wet and clean condition they received a severe shock. They suddenly discovered that their former boast of “know- ing when they had enough gas” was no longer applic- able. They had simply to take a whiff or two and presto! they were out of business. Gas Hazards at Resumption of Operations One of the greatest gas hazards is the seepage of gas through furnace walls, foundations and surround- ings whenever a banked furnace resumes operation. At such times gaseous areas will accumulate in most unexpected locations, and too much emphasis cannot be laid on the importance of the most rigid watchfulness at this time. At South Works our experiences during the past two years of alternate banking and “blowing ip” have resulted in the following method of procedure inder such conditions: Just before blowing up, two or three of our practice men are sent out to gather the men into groups and to explain that the furnace in question is about to resume operation. Each man is nstructed to watch his fellow workmen. The blower assigns a partner to each man whose presence some- what near the furnace is necessary, and these men are nstructed to watch each other for any symptoms of the elects of gas. Patrols, in pairs, are placed at safe ‘stances from the furnace and at locations that en- able them to see and prevent anyone approaching the ‘urnace from any direction. Many accidents have resulted and many lives have een lost by men working in a furnace or in its gas “quipment when such furnace was out of blast and dis- ‘onnected from other furnaces by a water seal only. ‘N unaccountable ways the water has been lost at the ae iolent slips on other furnaces have blown a OURA gas through the seal to cause serious trouble. ul¢ only positive means of preventing such accidents * ‘ne ironclad law prohibiting any individual or group inder ordinary operating conditions, from it any location in a furnace, dust catcher, _..._' Cryer, water seal, or any part of the furnace we wears he is protected solely by a water seal. ‘uch work is to be done the furnace in question protected by a plate or goggle valve. This ns of protection becomes very simple if with adjacent flanges for plate valves are ‘ beyond the dust catcher and just before + main. ith W orks each of our eleven furnaces is now ‘na it 1s possible to shut off any individual A LL blast furnate men will undoubtedly agree that ‘ddress delivered before National Safety it Milwaukee, Sept. 27 to Oct. 1 perintendent Blast Furnaces, South Works, 971 furnace by first filling a water seal and then tyrning a goggle valve or inserting a plate on the dead side of this seal. Under extraordinary conditions, occas.vns may arise when it is necessary to send a man into a place protected by a water seal only, but in such cases the man doing the work should either wear a gas hel- met, or where impossible to enter so equipped, should have a life line securely tied about himself, and ex- tended to a safe location outside of the manhole. The ordinary manhole provided in dust catchers, washers, gas mains, etc., is of such size that a man under normal conditions can just about squeeze through. It is an exceedingly difficult task to get a man through the hole if he is in a partial or compictely unconscious condition. In all future construction man- holes should be made large enough to freely admit a man fully equipped with a gas helmet apparatus. Provision is made on all of our furnaces for insert- ing a goggle or plate valve in the main when a furnace is to be relined, banked or down for repairs, as mentioned above. In some cases, however, the necessity might arise for repairs to be made at some point in our gas main where such provision cannot be made. In such a case when men are working behind a water seal only, it is our prac- tice to have the water seal carefully inspected regularly, the inlet and overflow outlet, water valves locked with safety locks, and the bottom discharge valve securely blocked or locked. We believe that these precautions carefully followed will adequately protect men while working in such locations. Where provision is made, it is our practice to insert the goggle valve or plate when men are going in a main, and to have the water seal also full as an extra precaution. Care of Gas Helmets From a safety, as well as an operating standpoint, every blast furnace plant should have an up to date, self-contained, breathing apparatus equipment, but it must be borne in mind that the most efficient gas hel- mets made are only safe when they receive constant attention in keeping up the equipment and when worn by men who have been thoroughly trained until they feel absolutely familiar with the apparatus. The re- sponsibility for maintaining our gas helmets in first class condition was at first put up to certain men in each branch of the department, but this plan did not prove a success and for the last two years we have had one man whose sole duty it was to keep our 21 gas hel- mets in first class condition at all times, and to take charge of training our helmet squads. Our breathing apparatus is housed in wooden cabi- nets with glass panel doors. These cabinets are of sufficient size to allow each set of apparatus to be hung at the height of a man’s shoulders. They were de- signed with two purposes in view: First, to make the apparatus accessible and ready for instant use of in- spection; second, to protect the apparatus from dust. The apparatus is hung completely assembled with the exception of potash cartridges, which are kept on a shelf immediately above the helmet. When a man desires to use a helmet for relief or emergency work, he inserts a new potash cartridge and, after putting on the apparatus, tests it thoroughly for leaks. If he desires to put on the helmet for practice work only, he uses a potash cartridge which has been previously used for this purpose, and is sealed with rubber stoppers. Our helmet man systematically in- spects each helmet once a week. If the helmet is in first class working condition he attaches a seal, and should this seal be found broken at any time it is an indication that the helmet has been in use since his last inspection. A written report is filled out after each pemnetarensisonense ROL 0 NA AIDE LOEB ANAS 5: inspection and a copy submitted to the assistant super- intendent in charge of that particular department. Before the war it was difficult to instill confidence of the workmen in gas helmets, but the trench helmets used for gases other than carbon monoxide received so much publicity in our newspapers during the war that men have lost, to a great extent, their fear of them. Each of our departments has a helmet squad consist- ing of men who have been examined by the company physician and thoroughly trained in the use of the equipment by our helmet man. This squad is made up of day and night men and at least three are always on the job on either day or night turn at each group of furnaces. A siren is blown in case of any gas emer- gency and all helmet men immediately proceed to the nearest helmet station and prepare to enter the gaseous area. Drills are frequently held, and several times during the past year certain men in the relief squad have been told to hurry to the office, get on a helmet and rescue a man from the bustle pipe of a furnace. When the relief man arrives at the bustle pipe he finds the fore- man lying down beside a bag of sand. The foreman then directs him to lower the bag carefully to the ground. The best record made so far is a total of 5% minutes from the time the man started to the office for his helmet until the bag of sand touched the ground below the bustle pipe. The furnace in question was located about 500 ft. from the office. One of the most recent developments in appliances to assist in overcoming the hazards of blast furnace gas is the appearance of a new carbon monoxide de- tector, which I note will be discussed by a later speaker. It may be stated that should this instrument be found practical and positive it will fill a long felt want in blast furnace practice. Hot Metal and Cinder Burns Considering the next serious hazard after gas, we come to hot metal and cinder burns. Here again em- phasis must be laid on the importance of safety think- ing. And a safety thinking workman thinks for the other fellow as well as for himself. The best evidence of safety thoughtfulness in an organization is the care and advice which older furnace men bestow on new em- ployees in regard to safety precautions. In these days of great labor turnover this lack of watchfulness of the older men over the less experienced may be the cause of many accidents. Several devices have been brought into use during the last few years to counteract the hazard of burns around blast furnaces. Among the most important of these may be mentioned the Bates cinder notch stopper, the Berg automatic mud gun and the Mullin tapping machine. At South Works we are at present installing the Bates cinder notch stopper on our furnaces as they are relined, and our experience with this device so far promises good results. Like all new equipment, it will require months of use to obtain the confidence and ap- preciation of the men. Two devices which have recently been put into use in our plant and which tend to cut down burns from splashing and sparking at the iron notch are a chain screen which is lowered in front of the hole at the end of the cast and through which the mud gun muzzle is inserted to stop the hole, and a splasher plate which is raised above the trough, and swung away from the hole at the end of the cast, by one man, operating a hand wheel, at a safe distance from the furnace. The keeper, first helper, and cinder snapper of each furnace are required to wear safety leggings when- ever the iron or cinder is running, that is, at flushes or casts. These leggings were unsatisfactory as origin- ally purchased on the market, but with some few changes to make them lighter and more flexible are now well thought of, and freely used, by our furnace men. Wire masks are sometimes used by the keepers when they close up the hole. These do not impede the vision and are preferred by our men over goggles. Two other devices which tend to cut down burns in our cast houses may be touched upon. One is the arrangement of sheaves and cables which are used to pull all shut- ters from a safe distance, thus making it possible for the man doing this to keep out of range of sparks or THE IRON AGE October 1920) shots of iron. The other is the heavy east ; which are conveniently located at severa] » the iron and cinder runners. These brid: possible to cross the runner without danger or falling into the stream of molten meta] Mechanical Hazards Taking up next the mechanical hazards. hoist undoubtedly stands first as the source «+ sa dents. It is true that the use of safety locks + rials enforced, has done much to overcome the great. rt of danger due to the possibilities of men being my over, crushed or caught by moving parts, but in spite of this safeguard, near accidents have demonstrated the necessity of some method of quick contro! to check the movement of the skips, should a man be found i be in danger. In order to take care of this condition we have installed safety switches, readily accessible to anyone standing at the side of the skip pit, so that by simply throwing a switch the power is cut off and brakes automatically applied to the hoisting machinery. As our furnaces are relined all skip inclines are covered, on the bottom and sides, with steel plates t prevent injury to those below from falling material. Owing to the compact construction of stock houses. serious collisions have occurred between scale cars where one car happened to be stationary under break- down repairs, and the other operating. Men working under the stationary car have been injured from the resulting shock. In order to prevent such occurrences, our stock houses are provided with suitable skids which are placed on the rails at a safe distance from each end of a car under repairs to protect the car. The usual form of snorting valve used to by-pass the cold blast into the atmosphere, when it is desired to take the wind off the furnace and the blow-off valves, which are operated to release the pressure from stoves taken off the furnace and put on gas, have given blast furnace plants the reputation of being the great- est noise producers in steel mills. It is safe to predict, however, that within the next few years blast furnace plants will be operating as silently as any other de- partment of the mills. Patent blow-off valves are now on the market which permit the discharge of air from three-pass stoves to be directed into the stacks. The muffling of two and four pass stoves is easily accom- plished by connecting the blow-off valve directly to the draft flue. The snort valve may be muffled in the same way, that is, by connecting the outlet to the draft flue. Both of these plans are at present in use at South Chicago, and we believe that the elimination of these violent noises is conducive to greater safety t the operating force, not to mention the prevention of partial or complete deafness of the man whose duty !t is to operate these valves. SKI} element Kelly Reamer Co. in New Home The Kelly Reamer Co., Cleveland, recently movec into its new plant at 3705 West Seventy-third Street, that city, and its shop committee held a house-warming party on Oct. 9. Features of the plant are extra heavy vault space to care for both the company’s and cus- tomers’ drawings, improved machinery and equipment for producing high grade tools of this nature. It is located in the new manufacturing district at the south west side of the city, and when city improvements an completed it will have two sides facing on a wide Dow's vard with good street car service over the West senate and West Seventy-third Street lines, and fine appro“ for auto traffic. Ornamental Iron and Bronze Manufacturers The thirteenth annual convention of the een Association of Ornamental Iron and Bronze Manufac- turers will be held at the Adelphia Hotel, Philadelpi® Oct. 18 and 19. Speakers of note will addr apne ae vention upon the subjects of industria: —- overhead and cost accounting, industrial rel tions, conditions, and other matters which are of er > held terest to the industry. The annual dinner wilt oe Oct ' evening of \™ at the Philadelphia Yacht Club on the 18, following an automobile tour throug ing plant at Hog Island. h the ship buile- Electric Smelting of Montana Manganese Practice of the Anaconda Copper Min- ing Co. in Making Ferromanganese — The Furnaces BY E. S. RING the year 1918 there was produced in the ited States 304,366 gross tons of manganese containing over 35 per cent manganese. Of sunt Montana alone produced 199,932 tons, or per cent of the total. Practically all of this from the Philipsburg and Butte districts. nistice caused an immediate curtailment of ese mining in Montana, owing to the ability of rn steel plants to again secure supplies of se ore from foreign sources. The manganese yn of the State of Montana in 1918 was than the total imports to this country for the 111, and would represent a substantial percent- s country’s normal requirements. view of these facts, the importance of this source of manganese cannot fail to be recog- ind a discussion of the problems arising in the of these ores in the electric furnace should be Character of Ores Montana ores are low in phosphorus and iron rably suited for the production of 80 per cent nganese. In the Butte district the Emma mine hief producer. The output of this mine during reached a maximum of 10,000 tons of rhodo- ore a month, the greater part of which was to eastern consumers. A typical analysis is WSs: Per Cent Per Cent 2.61 MgO 2.61 46.87 BaO 0.00 2.68 CO, 33.56 6.19 -——- 1.18 95.70 0.00 Undetermined 4.30 Total 100.00 psburg ores differ from those of the Butte hat they are higher in silica and contain ‘ principally in the form of the psilomelane, ‘ated oxide of manganese of more or less indefinite An average analysis is about as follows: Per Cent Per Cent 9.73 MgO ...... ‘ — 50.10 Bao . ate ’ — 3.83 Loss on ignition. « 12.80 2.90 —— 18.07 99.44 2.01 Undetermined vce Qe Total . , -190.00 ng it is possible to reduce the silica content « fniipsburg ores to at least one-half the per- above, with a corresponding increase in mtent Electric Furnace Plant at Great Falls iis the Anaconda Copper Mining Co. erected s, Mont., an electric furnace plant capable ‘) tons daily of 80 per cent alloy. The es was started in September. Three eady for operation at the time the ned, shortly after which time operation < of market for the product. msist of an open-top, shallow brick . (8.4 x 4.2 x 2.7 m.), outside dimen- walls are of red building brick, with ning. The shaft has a tamped lining ‘burned magnesite, with pitch as a ed lining is 3 ft. (90 cm.) in thick- f the crucible, and is brought up the t 18 in. (45 em.) above the tap-hole ; f+ sented at the fall meeting of the Ameri- Society in Cleveland, Sept. 30. The Anaconda Copper Mining Co., Great ¢ 973 and the Charge BARDWELL level. Cooling pipes are provided in the bottom, through which air for cooling is circulated. The inner dimen- sions of the crucible at the middle section are 22 x 9 ft. (6.6 by 2.7 m.) by 6 ft. (1.8 m.) deep. The furnaces are operated on 60-cycle, 3-phase alternating current. Two 24-in. (60 cm.) round amorphous carbon electrodes are used in a common holder on each phase. The electrodes are spaced 3 ft. (90 cm.) between centers in the holders and the pairs about 5 ft. (1.5 m.) on centers. The holders originally provided were discarded on account of mechanical difficulties and another very sim- ple holder devised. This holder is made in two entirely independent halves held together by pins and wedges. The long fish-tail cast integral with the holder makes it possible to avoid bringing cables out over the furnace, where they will be subjected to the hot gases. Water- cooling is brought about by a coil of pipe properly formed and cast in. The water connections for each half are independent. The holder is supported by yokes, which serve to keep the chains used for raising and lowering the holders up out of the heat. The winches for raising and lowering the electrodes are placed upon the bridge supporting the holder and electrodes, which bridge is insulated from the furnace superstructure by means of vitrified brick interposed between it and the superstructure. No trouble was experienced from failures of insula- tion during the time the furnaces were operated. The holders themselves were cast in sand molds from phos- phor-copper, and required practically no machine work. We found the contact surface ample and the holder suf- ficiently flexible to take care of the inequalities in size often existing between the two electrodes in the holder. A loosely fitting sheet steel sleeve was provided to slip down over the electrode. This rested on top of the holder and prevented the electrode being eaten away above the holder by the hot gases. When slipping electrodes the wedges were easily loosened, the holder raised and again clamped. The time required for slipping electrodes was not over 10 min. No attempt was made to protect the electrode exposed between the holder and the charge, except to keep the holder as close down to the top of the charge as was feasible. The substation from which electrical energy is sup- plied is located immediately back of the furnaces. It receives power at 110,000 volts from nearby hydro- electric plants of the Montana Power Co. Two 12,000 kva. General Electric transformers serve to reduce the voltage from 110,000 to 6600 volts, at which voltage it is delivered to the furnace transformers. Each furnace is equipped with one General Electric polyphase trans- former rated at 5630 kva., provided with taps on the high tension