The Iron Age 1923-01-25: Vol 111 Iss 4

THE IRON AGE New York, January 25, 1923 ESTABLISHED 1855 VOL. III, No. 4 Gray [ron Castings from Electric Furnace Possibility of Their Commercial Production—Acid and Basic Practice Compared—Ro6le of Heat Treatment BY LARRY ROM time to time in different technical journals icles have appeared discussing electric furnace gray iron in one form or another—some advocat- | some opposing, some recommending acid opera- ome basic—but as we scan the lists of manufac- rers in this country of basic or acid electric iron cast- ng we note very few who specialize in this work. There everal companies which are using the duplex process in con- junction with the cupola and there are sev- who are making inter- mittent heats of gray iron. From my per- sonal knowledge I know of many \s which attempted gray istings in tric fur- but, for some reason or ther, have dis- are eral lave make FRACTURES OF GRAY : From left to right: 1 mtinued this note the blowy condition: t. The 2—The bath has been carbon 3 Preliminary this test produ following article about 3 cent. 3—After rs the at- leading the suc- man u- of elec- furnace cast- devel- y the a prominent California shop. It covers the levelopment and experimentation in detail and nelusions to the reader. a year and a half ago a new plant was started electric furnace iron castings. As time went nade many gray iron castings, but had great n obtaining a soft iron. There was only one lake a free cutting, soft gray iron and that ising a large percentage of pig iron in the This, however, proved so expensive that it had ndoned. It was about this time that the writer 1 in, irnace at this time was operating on an acid nd it was decided to make the trial first with ice in this condition. The first heat was per per cent. 4—After addition of earbon here about 3.50 while slag is being brought spoon. Upper piece to the left is taken from chill. allowed, per cent. 5 to the ron manager, Bancroft & Ross, New Orleans. J. IRON MADE FROM test will vigorously boiled; note several blowy spots and the closer grain, radiating about 0.7 note “flery’’ appearance in the corners of ¢ and finishe a final casting poured against a partial Note the open grain and soft structure to the The final analysis was over 3.60 per BARTON charged with iron borings, sufficient ground coke being added to overcome any small oxidation of carbon. The borings were clean and had been taken from a mis- cellaneous grade of iron castings probably analyzing about 3.50 per cent carbon, 0.60 per cent manganese, 0.40 per cent phosphorus, 0.08 per cent sulphur, and 2.25 per cent silicon. The heat was melted down under ordinary acid conditions. As as the bath was in a molten condition a test was taken and poured into a sand mold, where it was al- lowed to remain until black, when it was quenched and broken. The fracture was rather close grained, such as would give a hard iron, espe- cially in small sized castings. To the furnace was then added 0.50 per cent silicon, the bath boiled with a green rod and another test taken and treated as above. This test showed a soft gray iron and the heat was poured. Castings from this heat machined easily, but were prone to have hard spots scattered over the different at irregular intervals. The above method was tried out several times, each time using the greatest care in the melting and finish- ing. From this series of melts the following facts were learned: soon STEEL SCRAP taken as as bath was melted soon 2 60 carbo! fracture show about the per cent to the the white boilings, the cent clearer more note freedom of over 3.25 mottled ; est piece, showing satisfactory carbon 6—After further additions of silicon, d condition. i from from center; carbon per silicon, structure Piece above test left where slow cooling was cent carbon on this heat faces Great trouble the hearth and the silicon again oxidizing It to slag off blanket several times during the course of a heat the was experienced with the slags, carbon tending to reduce the to form a heavy slag was always necessary this heavy impossible to the absalutely regulate the down fine It was silicon con- due to above while tents in metal; cause. Some heats would melt others would reduce at times as much as 1 per cent silicon. was always experienced great Difficulty up in keeping the carbon contents causing trouble with hard irons, even 269 270 THE IRON AGE though the silicons were from 2.25 to 3 per cent. This often gave rise to hard spots in ‘the castings, causing undue rejec- tions. he addition of extra amounts of c@gal or coke did not seem to overcome this point. Heats were spotty, one giving good iron and the next giving a hard iron, even though both were melted in exactly the same way, and using the same class of melting stock. Use of Gray Iron or Steel Scrap Our next set of experiments covered the melting down of common gray iron scrap. As this was so costly we did not attempt this as a commercial possibility, but merely to obtain data to see if the results differed from borings. The heats were charged and melted in a similar manner. With this, results were better and iron was obtained which was soft and reasonably free from hard spots. Some difficulty was experienced with the slags, but not nearly so much as with the borings. We attributed this to the fact that the carbon was in combination until in a molten condition, no coke being added to the bottom. We also found that as soon as the heat was melted the silica started to reduce at the expense of the carbon giving some low carbon heats. The iron was dirty and difficulty was experienced with sand and slag spots in the castings. Aside from the high cost this, however, was considered as a feasible method of operation. Our third step in this direction was the making of gray iron from steel scrap, principally borings and turn- ings. Coke or coal was charged in sufficient amounts to give the necessary carbon, and the charge was melted. Tests were taken and coke was added, and the bath boiled until the carbon was high enough, when the manganese and silicon was added, and the final test taken. The results from this series of operations were very irregular. On one heat we would get a carbon of over 3.25 per cent while the next would give us only about 2.75 per cent. It was, however, easier to regu- late the analyses and the iron seemed to pour cleaner, due to the lower sulphur contents. The iron was rather sluggish, due to low phosphorus contents, and had to be handled rapidly. From our acid bottom experiences it was found that gray iron could be made by any of the above methods, cheaply and well, with several defects. Hard iron was often encountered, hard spots were quite frequent, and the iron was always dirty and contained inclusions of a non-metallic character. The quality of the castings was very irregular as to composition and from a strict standpoint it was not to be considered as iron of the highest quality. Many of our customers required a high-speed machining iron and as we could not abso- lutely guarantee this product we turned to heat treat- ment to soften the castings. Heat Treatment of These Iron Castings Our first attempt was toward the softening and elimination of hard spots. Several sets of small sized castings were thrown into the electric furnace after the day’s run, and allowed to soak over night. In the morn- ing they were taken from the furnace, allowed to slowly air cool and then machined. The results were at first surprising, the hard iron castings machining readily and appearing free from any hard spots. Later this was found to be very unsatisfactory from many points —hard spots appeared from irregular cooling, castings cracked from being heated too rapidly and warping was frequent. A small oil-fired treating furnace was built and placed in operation. At once a great difference was apparent. There were no hard spots, the cracking dis- appeared and, after different experiments on placing castings in the furnace, warpage was eliminated. Our results were so good that further experiments were con- ducted with the idea of turning out gray iron castings of different hardness but of the same heat or analysis. This was found to be practical if carried out under eareful control. Castings were thus made from the softest iron to a very hard gray iron which could only be machined with difficulty, this class of work finding a large market in the cement and brick industry where a long wearing iron was desired which could also be machined. From the above experiments certain desired changes in operation were shown and exact methods of January 25, | 323 procedure were developed covering the manufactw)» of gray iron from steel scrap, borings, and other ir... of this kind. Gray Iron from Steel Scrap In the manufacture of irons from steel scrap. the point of greatest difficulty is that of obtaining « contents of over 3 per cent in the finished product. T} saturation point of the iron-carbon series ‘is |; close to 4 per cent carbon, and if the iron and the source of carbon were to be held in an intimate contact for g sufficient length of time, equilibrium at the above »oint would be established if no opposing conditions wer» t arise. In commercial practice these opposing condi: on: are the main points of failure. It has always been found that any material for the purpose of adding carbon to the bath will » in percentages of carbon obtained directly in prop: n to the ash content of the material used. It seems that materials containing a high percentage ash offi he body to a slag condition which materially inter/eres with the metallic absorption of the carbon by « physical means—that of a thin film of slag th: which the carbonaceous material cannot penetrat With this in mind any re-carbonizer used should b carefully examined as to its ash content. Und i caption such materials as graphite, petroleum ke (not gas coke such as is made by the gas companies and placed on the market in briquettes), pitch or retort coke, low ash coke, low ash anthracite coal, etc., offer an excellent material. Charcoal, while low in ash, recommended due to its low specific gravity which allows it to float very high on the bath and offers too much waste from oxidization. Retort coke known as “Queen Bee” is the most suitable material to use, bot! from the side of technical utility and cost. Slag on the bath is one of the greatest points detri- mental to successful carbonization and, until the car- bon is high enough, it should at all times be kept from the surface of the metal. If the bath is kept free of slag it materially aids the introduction of carbon into the metal. Iron will easily take up carbon to about 2.75 per cent without agitation. After this point is reached it will be necessary to boil the bath so that all of metal passes directly under the arc where the speed of carburization is very rapid. The presence of slag will interfere by the carbon reducing the silica and burning off as carbon monoxide. The silicon reaches the surface of the metal, combined with oxyge: silica, and the above is repeated at the expense of the sarbon. This boiling is best done either with green wood poles or with hoe-shaped rabble bars. The Practice Recommended Charge on the hearth of the furnace the carbonizing material calculated to 3.50 per cent carbon, the effi- ciency, determined by the material used, ranging from 50 per cent for common coke to 75 per cent for graphite, based upon the actual carbon contents. The materia: should be of small size preferably under % mesh Under no conditions charge any slag material. Now charge the metal and turn on the current, sealing 4!) doors as far as possible, as any air entering the fur- nace will only result in a needless burning up of ¢ar- bon. As soon as there are small pools of metal under each electrode, throw in these holes a small shovel of the carbonizer. This will tend to steady the arc, an¢ at the same time will furnish a spot of carbon direct!y where needed. This will increase the speed of melting as, during the heating up of the metal to its melting point, it will absorb carbon slightly and aid by a lower ing of its fusing point. Be sure that the doors are kep* well sealed at all times. As soon as the bath is melted open the doors and inspect the furnace. Any material on the walls can bé pushed in and the surface of the metal can be inspec’ for any slag coming from the bottom or from any dirt or other foreign impurities in the metal charged. If any slag shows it should be carefully raked off and sufficient of the carbonizer added to cover the surface of the metal. Take a spoon test and pour into a 54” mold on end. A good size test bar is about 1 in. square by 6 in. long. Leave it in the sand until black and then 25, 1928 with irregular crystals. THE IRON AGE 271 water quench. This test will usually show radiating from the center. To all who are familiar with will be clear white. The fracture will appear cupola white iron it is readily recognized. The carbon If a chemist is at is now at a point of from 3.25 to 3.75 per cent, but it imple should be sent to him for analysis— is good procedure to take another chemical test for final bon at from 2.50 to 2.75 per cent. If there calculations. f carbon on the bath it will not be necessary One can now add slag materials to form a blanket ny further additions; if not, enough must be for the metal and, as soon as thoroughly melted, add over the metal. It is very important at all manganese and silicon. When these are diffused a final -eep a good blanket of the carbonizer on the test can be taken for appearance of fracture. By now your carbon is sufficiently high. the chemist’s analysis will be back and, if the carbon metal is hot enough to run cleanly from the is high enough, it is safe to go ahead. At this point yne can go ahead; if not, it must be further never pour on a carbon lower than 3.35 per cent if in- When this temperature is obtained the bath tended for soft castings. If too low another boiling will SOME OF THE CASTINGS WHICH WERE HEAT TREATED 1 small wheel for light tapering back to a very soft iron illowed to coo n I tior ind The rim _ section is This was pulled from the furnace from h tandpoint he irface in. thick and is re- at a medium red, the face A buried gave good results Cr ng developed hard in order to stand in lime up to the center of the casting, ut the point where ib joined wear. The hub must be and an air blast thrown on the opposite rim and the treatment was slightly 1aft and during the treat- face. Results were excellent, and weré modified to overcome this The piece be kept soft. These cast- such that they could not be obtained was drawn and set the nd ' very well be cast in a in any other way. one-third of the way up After a few cks will develop at the No. 3 piece is a small face piece seconds in the sand it was re-moistened re rim meets the spokes. used in street car work and is machined giving a quick cooling with excellent heated to a bright red and all over. Due to the shape of the results in service soak the wheels were cores and the extreme thinness of the No. 5 is a bearing casting which d and inserted into a casting it was found very difficult to required a hard face on the circular pipe which tightly fitted obtain a soft casting, free from any hub, with a soft backing on the flat hub was surrounded hard spots. This piece was heated to part to resist strain Drawn and coal and covered with a good red and allowed to cool down placed around a water cooled chill, im was thus made dead in the furnace, totally eliminating any covered with lime and allowed to cool. he hub was still nearly red. of the previous troubles. No. 6 is a chuck plate for a lathe yn being broken showed a No. 4 is another piece of iron used which gave trouble with hard spots. iron in the hub, and a in conveyor belt systems, the roll on It was allowed to cool down in the gray on the rim. There which the belt travels. This is bored furnace results excellent ible with cracking or warp- in the hub and then faced all over the No. 7 is a section of a head from a roller. The piece wears out on the hard casting which could not be ma- a bearing block used by upper surface of the outside face. chined by ordinary methods howing istries on their conveyor For this it was required that the upper the way it machined and the manner face A ts required to be half of the roll be harder than the in which threads cut after being given to drill and tap while the lower half. After machining from the 1 softening treatment After being casting should be of a previously annealed iron the casting heated it was allowed to soak for two gray iron to eliminate was re-heated to a good red, drawn hours and then very slowly cooled in hardness should be at a from the furnace and set in wet sand the furnace by lowering the flame n the face opposite to A, up to the center line. The casting was from time to time _ MMMM citi ui i — evenee eonepreneneneraenvecsacnenmesaeners st scineresns seenssaneenter eaberryenssieenes sense seneeensenn s041 rveeesneqene led. Green wood poles are shoved in each usually suffice. In an emergency the electrodes can be noved from side to side under the surface of lowered into the metal with the power off, but as this is The metal will be violently agitated and the . so costly it is not to be recommended unless trouble rapidly rise in the iron. Five minutes boil- arises and demands quick action. g i ially raise the carbon content about 0.25 per Notes: Take your time to obtain good metal, for an ling on the temperature and class of material extra hour in the furnace is far better than a heat of e another test and repeat. same results, equilibrium is obtained. This bath and do not let any bare spots appear as that de- how a “fiery” fracture of large sized crystals notes oxygen is present and the carbon is burning off When two tests defective castings. Watch your coke covering on the : : : 5 3 a alain sane vnagsmges - to ~] bo above the metal. Above all keep the bath free of slag while raising the carbon. Keep careful check on sul- phur analyses as this element will invariably retard the carbonization if present in amounts over 0.10 per cent. Heat Log of This Method Charge: Wrought iron 5 ; 6,675 lb. Borings .. a os aa ak 10,150 lb. S:40-—Current on; 665 lb. ground coke (poor quality) was charged on the bottom under the scrap. 10:40—Nearly all melted; test taken, fracture estimated at 2.50 per cent carbon; chemist analysis later, 2.61 per cent; 100 lb. crushed coke added to bath; no slag apparent. 11:40—Test No. 2 taken: bath vigorously boiled for 7 min. from both doors (6-ton Heroult furnace) ; test too hard to drill by furnace drill press and tools; 130 lb. ferromanganese added. 11:45 Bath again rabbled and test taken; fractures show- ing better 12 :00—Test again taken, showing good: 100 Ib. ferrosilicon added. 12 :05—Test again taken, showing sufficient carbon; 100 Ib silicon added 12 :10—Another test taken shows gray and solid; carbon 3.13 per cent. 12:12—-100 lb. crushed graphite flake added and the bath rabbled with hoes for 6 min. from both doors; 100 lb. ferrosilicon added 12:17 Light slag added with 50 lb. coke and rabbled for 3 min.; previous test comes back 3.26 per cent carbon; final additions added and doors sealed 12:25—Final test taken shows a soft gray with center heavy in graphite poured into medium size machinery castings Analysis from casting Per Cent Carbon 3.40 Phosphorus 0.142 Sulphur 0.042 Manganese 1.16 Silicon 2.90 Kwhr.: 595 per ton of metal charged Procedure When Melting Iron Borings Charge sufficient borings to cover the hearth to a lepth of about 2 in. Then add the carbonizing mate- rial calculated to 0.50 to 1 per cent, depending on the cleanness of the scrap used. Care should always be used to eliminate any lumps of oxidized borings as they will only give trouble later on. The balance of the charge can now be added and the current turned on. As melting proceeds charge a small amount of coke under each electrode and keep the doors sealed as far as possible. When melted, run a bar over the bottom and pry up all “nigger heads.” Iron borings will some- times melt down and leave a heavy skull on the bottom, which will later come up and carry slag with it. This must all come up before proceeding any further. Care- fully rake off this slag, add re-carbonizer and boil. Take tests as in the use of steel scrap. These will show usually a hard gray and it will be necessary to raise both the carbon and the silicon by the afore-mentioned means. The final test should show an open grain with plenty of free graphite toward the center of the test piece. When this character of test is obtained pour. The practice used on iron scrap is exactly the same as for iron borings. The above methods are illustrative of those followed to obtain a soft, free cutting gray iron. There are, however, heats melted where it is impossible to obtain a soft iron, and as these cannot be scrapped a method must be devised to use them. This is attained by the use of annealing and heat treating. A small sized fur- nace, similar to any steel foundry annealing furnace, can be used with the best of results. Pyrometer con- trol is of course best, but, if not at hand, good results can be obtained by the eye after a few attempts. In our experiments we did not have a pyrometer so it is rather difficult to exactly describe our procedure. Annealing Iron Castings The castings are charged into a cold or slightly warm furnace, care being taken to support any pieces which would be liable to warp. The charging must be THE IRON AGE January 25, 929 such that each piece has good access to the heat ond | find here that a system of supporting screens work. ex. cellently. Charge a small amount of some ¢ar ona. ceous material on the furnace hearth to keep th. at. mosphere more or less neutral, then turn on. the |\ame. For this purpose gas gives the best results, as a ‘lan, can be obtained which is practically reducing, alt) ugh oil can be used. Heat up slowly to a bright red, al! w to soak sufficiently for all sections to attain this tem jera- ture, shut off the flame and allow furnace to cool down. keeping all openings tightly sealed. When blood warm, the castings can be removed from the furnace an. wi! be found to have softened enough to be machined at high speeds. Notes: Be very careful as to the flame temper: ture as iron is very easily burned, especially on the sharp edges of thin sections. Keep the furnace well scaled from air currents as a blast of air on the castings wil! result in hard spots. Heat and cool slowly. Variations in the Treatment of Iron Up to the soaking point all of the operations are the same. It is from this point on where the practice differs depending on what is desired. As slow coolin softens the iron, so rapid cooling hardens it. The prin- ciple to follow is that the harder the iron desired the more rapid the cooling. Another point in this process is the fact that one face can be hardened while the other parts of the casting remain soft. This is similar to chilling when cast, except that the chilled portion will be a hard gray instead of a white iron. This finds large use where only one casting is to be made, and where the cost of a chill for this piece would make the cost ex- cessive. The exact methods of procedure will depend upon the character of the iron desired and the class of casting to be treated. There are many ways to obtain this rapid cooling air, oil and water, wet sand, iron plates, water cooled pipes, etc., so arranged that the portion to be chilled is kept apart from the body of the casting. The hard- ness is best regulated by the temperature of the piece at the start of chilling. If chilled at a good red heat until cold, the iron will be harder than if the chilling is started at a lower red. Iron is very easily affected by this treatment and, after becoming used to the methods, one will find that surprising results can be obtained. One illustration shows some of the castings treated. The foregoing examples are given, not as a text, but as concrete examples of results obtained. While, due to lack of equipment, our results and methods of operation were rather crude the fact remains that many castings were saved which ordinarily would have been scrapped. Not only that, customers were given cast- ings which they desired and which gave real service, but new lines were developed and work was taken which formerly had been refused. The new lines and markets developed were such as to make the undertaking highly profitable. Operations on a Basic Bottom Up to this point we had successfully eliminated al of our troubles due to hard and spotty castings but were unable, by even the strictest practice, to eliminate dirty iron. Castings would be poured using skim gates, “buzzers,” and almost every means known to give clean iron, but with no success. Ladles were carefully exam- ined and the bath was carefully skimmed before the pour. Iron was poured which showed absolutely clear in the ladle and, during the pour, there was no dirt ris- ing in the heads or skim gate and yet, upon machining the castings would show up with dirt or slag pockets, sometimes pieces as big as a walnut appearing in the surface of the work. Another trouble arising were !"- terior shrink holes and small gas pockets. Larger heads were tried, heavy feeding was resorted to, but these troubles still remained. It was thought at first that some of these troubles might be caused from the melting stock so duplexing from the cupola was tried. The dirt still appeared 4! intervals so it was finally decided to change our oper ation to basic. The furnace was changed over and the results were at once apparent. Castings were obtained M ranuary 25, 1928 vere of a real quality iron. There were no dirt spots and it was a very much easier matter to ft iron than by the acid operation. The qual- .e iron was better, it appearing much tougher machining easily. This was explained as fol- iron was being held under a heavy reducing slag od of about three hours, eliminating all dirt and c impurities which rose up and combined with the nhur was cut down to a minimum with the con- ecrease of its attendant evils. ere was no reducing of the hearth by the carbon, much easier to obtain high carbon irons. Silicon were easily controlled. There was a saving of to the reducing action of the slag. Carbons as 0 per cent were easily obtained by the use of steel ising steel scrap as the base, gray irons of high nd great toughness could be obtained by the lower- e phosphorous contents. The higher heat of the irnace gave such temperatures as to easily run these Shrink and blow holes disappeared due to the de- powers of the basic slag. fective castings from all sources dropped from the eure of 12 per cent to under 5 per cent during t week and, as operations progressed, they were entirely eliminated. The greatest point of the on was the fact that customers were highly As many stated “they did not know that gray tuld be made of such high strength and still ma- readily.” From these results it was, of course, to adopt basie operation, While the actual costs etal were several dollars a ton higher, the great in defectives and complaints were so lowered ‘ operation was a great deal cheaper than any- ver before obtained. With a power rate of from s0c. to le. per kwhr., the conversion costs averaged it $15 per ton, which with borings at $6 gave a re- markably low cost to the molten metal. Iron borings were used as much as possible as they melted quicker nd gave a saving of about $3 per ton in alloys. Our » was carefully checked and a standard method procedure was adopted. Fine Iron from Cold Scrap fhis practice covers the manufacture of the highest f gray iron it is possible to make under pres- irgical conditions and, while the results are y those for the Pacific Coast, there is no doubt vhat makers in other localities could profit by our nees [he scrap, as clean as possible, is charged on the + intil about half is in the furnace. Then about lributes to the Late Samuel T. Wellman lributes were paid to the memory of the late imue! T. Wellman at a meeting held by the Associated hr Societies of Cleveland Jan. 9. This was the st meeting of a series to be held by this society on the ind steel industry. The r-seting was designated ‘a Wellman memorial night and a number of speakers inted personal reminiscences of their association Mr. Wellman and referred to his important con- : to the iron and steel industry in the develop- the open-hearth process imes H. Stratton, engineer of construction Well- n-Seaver-Morgan Co., of which Mr. Wellman was ‘the founders, read a portion of an address made Mr. Wellman at the time of his election as president ‘he American Society of Mechanical Engineers in the growth of the open-hearth industry and ¢ F wed lantern slides of various early types of open- th furnaces, . \ se Swasey, vice-chairman of the board of the War & Swasey Co., paid tribute to Mr. Wellman metallurgist and manufacturer. He said he | Mr. Wellman were close friends for a third of a ind had traveled much together abroad. He ind Mr. Wellman an ideal traveling companion. He “cared Mr. Wellman’s character could be summed up THE IRON AGE 273 100 lb. of small sized carbonizing material is added, together with 1% per cent of the charge of crushed, dead burned, lime. The balance of the charge is put in and the current turned on. The doors are kept sealed as much as possible and when the entire heat is melted the walls are scraped of any adhering scrap, and the bottom is freed of any lumps. The current is kept on until the metal is fairly hot when the first metal test is taken, and allowed to cool to a black in the sand. Quite often the metal is now ready to pour without any more treatment. If not, boiling with more coke is re- sorted to and small additions of silicon may be made. If it is necessary to do much boiling to raise the carbon, the bath will have to be slagged off. The carbon will raise more rapidly on the basic hearth than on the acid. When this element is as high as desired the fin- ishing slag can be added and the heat finally cleaned of any gas. This final slag is composed of 1% per cent of the charge lime, 25 per cent of the lime spar, and a few shovels coke. This is best when used in the ground condition and thoroughly mixed as it seems to become molten easier. Basic slags on iron are prone to lump and it is often necessary to use large amounts of fluor- spar to increase the fluidity. Rabbling with a flat bar will usually mix up a slag fairly well. This slag should be worked over unto a regular carbide one, and the metal held under this until tests show a finished iron. As the heat has already been held under a heavy lime slag up to this time it is very seldom necessary to hold for any length, as the sulphur and gases have usually been eliminated under the first slag. I find it good practice to work the heat at this time to eliminate any- thing held in the metal. A few minutes of heavy rabbling will usually lift up any included slag and leave a free, clear iron. Just before pouring carefully rake the bath free of all slag and coke or it will foul the ladle in pouring. A tea spout ladle is recommended on this class of casting work, lined with a rammed magnesite. I find that ground magnesite mixed with sodium silicate as a binder gives excellent results. If the metal is poured very hot and allowed to stand in the ladle for five or ten minutes any small slag spots will rise and can be skimmed, When I entered on this work, I began with an un- biased mind as to whether acid or basic practice was desirable. I was not swayed by previous experience or by what has been written on the subject, but took re- sults as I found them. They are not given as absolute, but are merely the experiences of one man. I will leave the reader to his own conclusion as to which method is preferab!e, for what is preferable for one may not be so for another working under totally different conditions. in three words “Noble Christian gentleman.” He was greatly impressed by what Mr. Wellman had done for the steel industry of the whole world when he saw Well- man open-hearth charging machines in use on opposite sides of the globe, in France and in China. W. G. Hildebran, assistant secretary Wellman- Seaver-Morgan Co., read a sketch of Mr. Wellman’s life that Mr. Wellman dictated to him a number of years ago. Five-minute addresses were made by John McGregor, C. C. Smith, F. Moeller and A. D. Hatfield, who had been closely associated with Mr. Wellman. Preceding the speech making program, a banquet was held in the ball room of Hotel Winton, where the meeting took place, and both banquet and meeting were largely attended. Sixty officials of the sales department of the Beth- lehem Steel Corporation made an inspection of the Lackawanna plant, Buffalo, Jan. 12, following the gen- eral sales meeting at Bethlehem, Pa. Luncheon was served at the plant at which addresses were delivered by E. S. Knisely, general sales agent, Bethlehem Steel Corporation; Timothy J. Burns, general manager, Lack- awanna plant; G. H. Blakely, manager of plate and structural sales department, and E. S. Illig, in charge of sales for the Buffalo district. oe nami ee ; ae ont seine thee. - a st er ae > a, ta t at a” 1 ne 274 Rotor Design the Feature of New Motor The Louis Allis Co., Milwaukee, has placed on the market a new type HD motor, the outstanding feature of which is the construction of the rotor. The entire winding of the rotor consists of an in- tegral sheet of copper, punched and formed by a special mechanical process. This one-piece winding is machine wrapped around the rotor core as shown in the illustra- tion, the copper bars being expanded into the core slots by swaging. The single joint, which extends through the two end rings, is silver welded, after which the metal at both The ing connections is processed by means of a contracting oper- ation. This is said to re-harden the copper at the point where the heat, applied during the welding, softened it, the treatment being intended to produce a lapped, silver welded joint of maximum strength. It is claimed that the rotor winding, except for the joint in the two end rings, is as substantial and-indestructible as a piece of pure copper pipe. The comparatively thin copper stock, of high ther- mal conductivity, used in the fabrication of the rotor winding, serves also to readily conduct the heat gener- ated in it toward the ends of the rotor bars, where the heat is dissipated through the action of malleable iron fans. The rotor bars themselves constitute a blower, which aids in the ventilation. The rotor core is a self-contained unit and may be pressed on and off the shaft readily, as it has a straight keyway. Otherwise it is largely conventional except that it employs open slots without the usual overhang- ing tips. The electrical characteristics are said to have re- ceived equally careful attention also. Unusual starting and running torque are claimed, and the motors are guaranteed to carry their full rated load continuously with a temperature rise not exceeding 40 deg. C. After the ultimate temperature has been reached, they will carry 25 per cent overload for two hours with a tem- perature rise not exceeding 55 deg. C. The motors are available in standard industrial sizes, voltages and fre- quencies. Domestic sales of oak leather belting for December are reported by the Leather Belting Exchange at 451,957 lb. valued at $784,597, or an average of $1.74 per lb. This compares with November sales aggregating 467,816 lb. valued at $826,164, or an average of $1.77 per lb., and with sales in December, 1921, aggregating 285,852 lb., valued at $433,060, or $1.67 per lb. The returns are from companies representing about 60 per cent of the total product. Continued improvement of the employment situation the country over is reflected in the report of the De- partment of Labor for December. New England re- ported overtime employment in the textile industries, while the district including New York, New Jersey and Pennsylvania, reported comparatively better conditions than in former years at this season. The condition was virtually the same in all States. THE IRON sists tegr AGE January 25, 1 23 Center Foundry & Machine Co. Goes to ».y Location March 1 On or soon after March 1, Center Found: & Machine Co. will move from its present locati Twentieth and Main Streets, Wheeling, W. Va., new plant in Warwood, a few miles north of Whee «, The new plant now nearing completion provides gi , area, permitting a much greater production, the old one, and it will be possible to make | castings, since the crane lift in the new foundry ft., as against only 12 ft. in the old one. The new foundry is 200 ft and 50 ft. wide, made up of bays, 25 ft. wide, of mill con tion, steel sash and monitor ‘y; roof. There are two cupolas, on of 20 tons and the other of 1' capacity, and the foundry is served ‘ by a 20-ton and a J0-ton crane Flask storage yard, 30 x 100 located at one end of the foundry building, while at the other ar the chipping shed and ma shop, covering an area 30 x 1 The company’s land holding tend 600 ft. beyond the ma Entire Wind Of Rotor Con- shop, making possible furth Of An _ In- pansion. Pattern storage bui g, al Sheet Of which is erected, contains (0 Copper sq. ft. and is adjacent to th tern shop, which is housed separate building. The plant is well laid out and embodies most modern ideas in foundry construction. The con plans no departure from its present lines, chiefly mill castings, with a jobbing business as a sid but capacity will be double that of the old plant individual castings of greater size can be made be of the higher clearance of the new unit. Moving Pictures Show Making of Cast [ron Pipe by DeLavaud Process At the annual meeting of the Philadelphia Foundry- men’s Association, Inc., held Jan. 10, at the Manufa turers’ Club, the members and guests were enlightened as to the making of cast iron water and gas pipes | the DeLavaud centrifugal pouring system by means of moving pictures which were shown through the courtesy of the United States Cast Iron Pipe & Foundry Co John T. Capron, of the company, explained the pictures and answered questions. The pictures were mad interesting through the fact that they compared and new methods. Mr. Capron and his compan) given a vote of thanks for the instructive evening The officers of the association, including Frederick M. Devlin, president, and Howard Evans, secretary, were re-elected for the coming year. Mr. Devlin suc- ceeded his father, the late Thomas Devlin, having been appointed to the office following his father’s death. Inasmuch as the New England Foundrymen’s Ass0- ciation was holding its annual meeting in Boston 00 the same evening, a telegram of greeting was sent & that organization. The meeting was preceded by a dinner and was one of the largest held in some months. more ld = The Studebaker Corporation has announced that will build and ship 35,000 cars during the first quart? of 1923. This is within 2200 cars of the record second quarter of 1922 and 13,000 more than were produced during the quarter just passed. The report of the Detroit Employers’ Associatio? for the week ending Jan. 16 shows an increase of 5461 over figures given a week ago, or a total of 14,0"! employed as of that date. The number employed 4 ye" ago was 109,703, while in 1921 it was 35,466. iba’s Duty-Free Manganese Ore Supply Deposits Estimated at 700,000 Tons, Important to United States in Case of War, But Costs Are High and Operations Limited BY PAUL M. TYLER mportance to the American steel industry, in ( j w of the new conditions surrounding the nanganese situation as a result of the new tariff, privilege of importing manganese ore from Cuba e United States free of duty under the provisions iprocal treaty entered into by the respective gov- ts in 1902. Under this treaty it was provided | articles which were on the free list under the y tariff of 1897, which was then in force, should of duty when imported from Cuba so long as aty remained in effect. This treaty, which also s for preferential treatment of other Cuban s to the extent of the remission of 20 per cent luties collected at the ports of entry, was not ted in succeeding tariff acts, including the Ford- Cumber act which went into effect on Sept. 22, this present tariff act, a protective duty of lc. is levied upon the metallic manganese contents ported ore, corresponding to 22.4c. per unit of ranese contained. A duty is also placed upon the vanese contents of ferromanganese which compen- ; for the duty on the ore and also affords some pro- n to the manufacture of the ferroalloy in this coun- These rates were intended doubtless to be applied nports from all countries. Actually, however, ow- the fact that manganese ore was in the free list the tariff act in force at the time the treaty with Cuba was consummated, manganese ore can still be im- ed into the United States without payment of tariff s, provided satisfactory evidence is presented to that it was produced by Cuban mines. rmal recognition of the situation has been made Treasury Department and during the last week ember notices were sent to the collectors of at the different ports, stating that articles were on the free list in the tariff act of 1897 Vingley) continue to be entitled to free entry into the States when the product of the soil or industry i, whether or not they may be in the dutiable the tariff act of 1922. Cuban Mining Costs High er normal conditions, the manganese ore deposits 1 have not proved capable of furnishing a very itput of high grade ore at a cost which would t marketing in competition with the more cheaply res of India, Russia and Brazil. There have erlods of stimulation from time to time, and the war Cuba finally attained a record pro- f£ more than 83,000 tons in 1918. Several claims were opened up and actual production \ined from many of them. Few Cuban prop- wever, were able to operate at a profit under ‘onditions even when prices were mounting more a unit and American smelters were less r as to the quality of their. ore supply. ind Crane* state that in 1918 mining and ‘osts ranged from $5 to $8 per ton of product t points and that transportation to railroad 32 to $10 per ton. Their estimate as to aver- ‘osts toward the end of the war period was m, f.o.b. Cuban port, but this relatively low vas attributed to the fact that the two largest properties were situated practically on the It may be further noted that this figure did nese, Uses, Preparation, Mining Costs, Etc.—U. S. Mines Bull. 173 (1920). gineering and Mining Journal, Jan. 22, 1921. 275 not cover amortization of investment and probably made no allowance for depletion, although it did include cer- tain other general charges. In discussing future pos- sibilities, these authorities came to the conclusion that the cost of producing Cuban ore would eventually drop to $11 or $12 per ton, which is equivalent to at least $13 or $14 per ton at United States Atlantic seaboard points. While some ore may now be produced at a little under these figures, subsequent developments have tended to confirm the estimates made at that time. There is not much prospect of Cuban manganese being marketed profitably at less than about 35c. a unit. Aside from the matter of cost, Cuban ores have the reputation of being variable in quality and are char- acteristically high in silica. There are one or two important exceptions to this statement, as evidenced by the continued shipments of high grade chemical ore from Cuba since the armistice, but the furnace ore has been generally low grade. Deposits Mostly in Oriente Most of the manganese mines of Cuba are situated along the south coast, being found in the provinces of Oriente, Santa Clara, Matanzas and Pinar del Rio. The only extensive deposits, however, are in Oriente, where manganese is found in three districts, one north of Santiago, another south of Bayamo and Baire, and the third on the Caribbean coast between Torquina Peak and Portillo. The Santiago district is the only important producing area, although there are moder- ately large properties in the Bayamo-Baire district. In the province of Santa Clara, a little ore has been found near the Caribbean coast west of Trinidad and small deposits occur in Pinar del Rio, north of the city of the same name and also farther west, near Mendoza. The principal groups of mines, in order of their im- portance, are the Ponupo, the Cristo and Cauto. Both the Ponupo and the Cristo properties are owned by Aguilera & Co. The Ponupo group is located practi- cally on the railroad and has been operated on a fairly large scale since 1898, the first shipment having been made in 1895. The grade of the ore in later years has tended to become poorer, but these properties are cred- ited with ample reserves of good quality ore (as manga- nese ores run in Cuba). The Ponupo mine was re- ported idle in 1920, whereas in 1918 it was producing in the neighborhood of 3000 tons of furnace ore a month. The Cristo claims owned by the same com- pany are much smaller, but the product in 1918 (when both were operating) was running higher in manganese, although most of the ore had to be washed. Recent analyses of the Ponupo ore show an average content of 38 to 40 per cent manganese, although pub- lished data as to earlier operations indicate as high as 53 per cent. Some of the Cristo ore carried 46 per cent manganese as shipped. According to D. F. Hewett of the U. S. Geological Survey, the Cauto group in 1914 was mining ore containing from 43 to 47 per cent manganese, 9 per cent silica, 2 per cent iron, and 0.05 per cent phosphorus and was also shipping some chem- ical ore containing 85 to 87 per cent manganese dioxide and, presumably, sufficiently low in iron. The Cauto mines are owned by the Cauto Mining Co. and are located at San Nicholas in the Santiago district. The production during the peak period of 1918 was at the rate of about 2000 tons a month. The only company that has maintained production is an American concern operating at Buecito on the fringe of the Bayamo-Baire district. As reported by Weld,** the output from this +e, i ste anes a a pera ais ic 276 THE IRON AGE property in 1920 was 3000 tons of chemical ore and 1000 tons of metallurgical ore, which constituted the only new production from the whole country in that year, although some 2000 tons was shipped from stock- piles in Santiago and in Boqueron. A Government Investigation On account of their close proximity to this country, the manganese resources of Cuba are of extreme im- portance to the United States in time of war. Ernest F. Burchard of the U. S. Geological Survey, and Albert Burch of the Bureau of Mines visited, in 1918, practi- cally all the Cuban manganese deposits that were known at that time. Much of the information thus ob- tained with respect to individual properties and the occurrence of the ore was incorporated in an article published by the former in 1919.+ This constitutes the best published record, at least, of Cuban manganese properties and should be consulted by any one who is seriously interested in the subject. According to this authority, the manganese deposits are found principally in metamorphosed sedimentary rocks (limestones, sandstone and shale), although at one locality the ore occurs in rocks of volcanic origin. The ore bodies are characteristically surface deposits, but in some places the manganese extends to a depth of 100 ft. or more. While the deposits vary materially in form and in their mineral associations, they may be loosely classified into three general types: (1) De- posits in bedded rocks, (2) deposits in irregular masses of silicious rock (locally termed “bayate” or jasper), and (3) deposits of nodules and fragments in clay. Most of the largest and richest deposits are associated with jasper. The limestone replacement deposits are also rich, but they are scarce and generally small. The third type usually yields good ore when the clay is re- moved by screening and washing, but the deposits of this type are neither numerous nor extensive and doubt- less the cost of washing would often be prohibitive. There are several types of bedded deposits, but a com- mon occurrence seems to be a mixture of poorly con- solidated tuffaceous material, pink clay (in granules), zeolite minerals and manganese dioxide. Silica Removal Difficult With respect to the character of the ore itself, Burchard reports that it consists of some or all the oxides—pyrolusite, psilomelane, manganite, and wad. A little braunite was identified in samples from one local- ity, but this is the only evidence of silica combined with the manganese mineral, as no manganese silicates have been found. As there are also no carbonate ores, the possibility of beneficiating these ores and especially of eliminating the excess of silica by mechanical means naturally suggests itself. The descriptions, however, of the different ores and examination of various samples show that the ore minerals are so intimately mixed with the silica-bearing matter as to prevent the economical removal of this objectionable constituent which has done so much to restrict the consumption of Cuban ore in American furnaces. There is usually no trouble as to phosphorus which ordinarily runs less than one-tenth of 1 per cent. Iron contents are quite variable and the analytical data available do not indicate any definite ratio of iron to manganese either for the country as a whole or even for different parts of the same property. Returning to Burchard’s report, for example, we find that at one of the larger properties the milling ore ranged from 26 to 31 per cent manganese and from 6 to 10 per cent