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By W. B. Clark

IN OPERATING the Alpha mine of the Consolidated Coppermines Corp., Kimberly, Nev., it was necessary to pump out approximately 1200 gallons of waiter per minute to prevent the mine being flooded. There were three levels in the mine at which water accumulated and from which it was pumped, the 1200, 1400 and the 1800- ft. levels. At each, the pumping equipment was installed in duplicate so that if for any reason one unit was out of commission the other would be available to prevent flooding. The two centrifugal pumps at the 1200-ft. level were 600 hp. each; at the 1400-ft. level, 100 hp. each; and at the 1800-ft. level, 300 hp. each.

Jan 1, 1933

By AIME AIME

I N JUNE, 1918, at a meeting of the American Society of Mechanical Engineers in Worcester, Mass;, a resolution was adopted for a committee to investigate the aims and organization of that society. This was followed subsequently by similar independent action on the part of the Society of Civil Engineers. The other two Founder Societies were approached and requested to appoint similar committees, the four committees to combine as a .Joint Development Committee, later called the Joint Conference Committee, to investigate what might be done in the way of coordinating those activities of the Founder Societies which ape of common interest, and which were then being pursued separately. The Joint Conference committee worked diligently -for almost. two years and. brought forth a tentative as outlined in its report which was published in full in MINING AND. METALLURGY, December, 1919. It recommended the formation of a nation-wide organization to be composed of representatives' of all of -the engineering societies, local, state, regional, or national, the object to be to further the interest of the public through the use of technical knowledge and engineering experience, and to consider and act upon matters common to the engineering and allied technical professions. Whereas the technical societies have large fields of endeavor in welfare work, and their prime. efforts are 'still in technical lines, this new organization was to be devoted entirely to service, looking to the welfare of the nation and the engineering profession, and to service for the public in local and state affairs.

Jan 1, 1920

By Robert T. DeGavre

The $650 million financing for Into Ltd.'s Soroako nickel project is a story worth telling-not only because the project itself represents a significant achievement but also because there are certain important lessons that can be derived from our experience in financing the project. A critical appraisal of the methods and successes in the financing plan is presented in this article, in light of goals which Inco sought to achieve. A technical assessment of the project is not included, since Inco Ltd. has submitted a series of papers on this subject at the International Laterite Symposium as part of the 108th Annual Meeting of AIME in February 1979. Progress in developing and financing the project is encapsulated in the accompanying project factsheet.

Jan 3, 1979

By RICHARD MAIZE

IN this critical period of our history, the coal industry of the nation, faced with many obstacles, performed its work safely during the first ten months of 1943. Thousands of the younger mine workers were inducted into the armed forces of our country and in many instances their jobs have been filled by others without much if any experience and training. This situation alone would seem to be sufficient to interfere with the safe and orderly operation of the industry but the Government's demand for a substantial increase in coal tonnage over that produced in normal times introduced a hazard which always accompanies speed, regardless of the skill of the worker.

Jan 1, 1944

By Albert Sauveur

IT is not without some hesitation, and even misgiving, that I venture into a discussion of the now classical Roberts-Austen Roozeboom diagram, lest I too fail, like so many other writers, in giving a satisfactory and logical explanation of these interesting curves. Roozeboom's original diagram is reproduced in Fig. 1. The generally accepted meaning of the various curves has been so often described before this Institute that it will suffice to recall it briefly before passing to my own interpretation of the changes involved.

Nov 1, 1906

THE Johnson award for 1926 was given to T. L. Joseph for his experimental work on blast-furnace operation. When the Bureau of Mines undertook its experimental blast-furnace investigation in 1919, a number of operators and metallurgists were doubtful as to the practicability of small-scale tests. Several pre-vious attempts, outside the Bureau, to operate small furnaces had been unsuccessful. However, pig iron was produced in three and four-ton furnaces during the first half of the nineteenth century. The operation of a small furnace did not therefore seem an impossible task. This point of view, together with a realization of the importance of problems connected with the pro-duction of pig iron, prompted the Bureau to undertake this work. Such problems as the feasibility of using charcoal briquets as a fuel, the application of oxygen enriched blast, and the use of new ores and raw ma-terials, in general, can be investigated only at consider-able cost on full sized furnaces, while with an experimental furnace they can be conducted at a com-paratively ;small, cost. The results of small-scale tests are sufficient to determine whether the problem. War-rants the expenditure required for a trial on a com-mercial scale. The accompanying photographs and chart show the various stages of the experimental furnace development. Some idea of the size and shape of furnaces which were tested can be had from the development chart. In oper-ating furnaces A to F, a series of changes were made to increase hearth temperature. Perhaps the most im-portant change was the position of the tuyeres with respect to the bottom of the hearth. The height of the tuyeres above the hearth was gradually increased and the hearth diameter decreased. It was shown by this series of furnaces that metal and slag are the chief source of heat supply to the crucible. For this reason there is a minimum rate at which these materials can be brought into the hearth of a small furnace if it is to function properly. The rate of slag "and metal fall are determined by the burden on the furnace and the rate of blowing. Due to lack of funds necessary to provide ample blowing equipment, hot blast stoves, essential mechani-cal features, and to meet operating expenses, it. was necessary to work with much smaller furnaces, such as G to K shown in the chart. The particular object of these tests was to study the extent to which reactions could be speeded up by decreasing the size of the stock. One decided change, noticed at the beginning of this series of tests, was the effect which coke size had on the production of a strongly reducing gas. Furnace G, 22 in. high, operating on coke crushed to pass 10 mesh, made a gas richer in carbon monoxide than did fur-naces A to F, operating on run-of-the-oven coke.

Jan 3, 1927

By E. A. Anderson

THIS seems to be the year for superlatives in A.I.M.E. meetings. The programs of the various Divisions and Institute committees offered an abundance of interesting and valuable information in the form of technical papers, symposia. and lectures to large and interested audiences. The Institute of Metals Division may hold up its head with pride for its own program. With six technical sessions, three full-day symposia, and the annual I.M.D. dinner, four meeting days were not enough and many simultaneous sessions were required. The quantity and quality of the paper were equaled by the numbers and interest of those attending.

Jan 1, 1944

By M. Kashiwada

The zinc leach residues are introduced into waelz kiln to fume volatile metals and before the end of 1967, the waelz-fume containing zinc, lead, cadmium and indium was directly recycled back to the leaching process for the production of electrolytic slab zinc. However, since 1968, we have been recovering with success those valuable metals contained in the fume separately instead of direct leaching. According to the improved process, the waelz-fume, after being mixed with chloridizing agents, is fed into the rotary kiln to be roasted, wherein most of lead and cadmium content is collected as fume and most of zinc remains in the calcine. Zinc calcine thus obtained, containing 70 to 75 per cent zinc and, less than 1.0 per cent lead is sent to zinc plant for further recovery and the fume containing 40 to 50 per cent lead and 3 to 6 per cent cadmium is further processed to recover lead, cadmium and indium. The advantage of this process can be secured to the utmost when it is combined with the following subsequent treatments. (a) Blast furnace smelting of non-magnetic waelz slag to recover copper, silver and gold as matte. (b) Gallium recovering process from magnetic waelz slag. (c) Soda process of lead bearing cake produced after removing cadmium and indium from the said fume. Thus the extractions of zinc, lead and cadmium from leach residues account for 87 per cent, 72 per cent and 85 per cent respectively.

Jan 1, 1970

By George A. Roche

Investment in growth stocks is the most assured way of achieving superior, long term investment accomplishment. There are many criteria used to select growth companies but the most important is a combination of superior management operating in an industry with above average growth potential. This growth stock approach is the cornerstone of investment strategy for two of the three mutual funds sponsored by the Price organization and for its private clients. However, during the past five years inflation has accelerated due to a variety of factors including the inability of government to meet seemingly unlimited needs with limited revenue sources.

Jan 4, 1972

By AIME AIME

THANKS to the excellent preliminary work of: the Division officers and the local committee the fall meeting of the Coal Division at Bluefields was a brilliant success. West Virginia was at its best with its beautiful mountains, good roads and foliage, just beginning to turn to autumn colors. The meeting began on time and was kept on time throughout. The papers were-well prepared and, being on subjects of live interest, provoked 'lively discussion. One factor in bringing this about was that they were not too numerous and that with one exception copies had been submitted in advance a sufficient time to permit of them having been studied. The Friday morning session was presided over by John .J. Lincoln of the Crozier Coal and Coke Co. and president of the Pocahontas Coal Operators Association. After brief announcements by Thomas H. Clagett, chairman of the local committee, regarding plans for the two day's involved, and by Howard N. Eavenson, chairman of the Division, the reading of papers was taken up.

Jan 1, 1931

By Harrison Everett Ashley

Prof. Hofman's diagrams, Figs. 5 and 7 of his paper, which are reproduced as Figs. 1 and 2 of the present contribution, confessedly fail to show comprehensively the properties of the silicates investigated. Each curve is carefully discussed, and the author has evidently drawn all the conclusions that can be thus reached; but he says :* "The curves do not show, as was hoped, any simple connection between silicate-degree, percentage of lime, and minimum of formation-temperature." There is, therefore, in this case, an excellent opportunity of

Jan 1, 1902

For the year ending February, 1919 PRESIDENT SIDNEY J. JENNINGS NEW YORK, N. Y. PAST PRESIDENTS L. D. RICKETTS NEW YORK, N. Y. PHILIP N. MOORE ST. Louis, Mo. FIRST VICE-PRESIDENT C. W. GOODALE BUTTE, MONT. TREASURER GEORGE D. BARRON NEW YORK, N. Y. SECRETARY EMERITUS ROSSITER W. RAYMOND, NEW YORK, N. Y. SECRETARY BRADLEY STOUGHTON NEW YORK, N. Y.

Jan 1, 1919

In accordance with the provision of the Constitution, notice is here given to all Members, Associates, and Junior Associates, that the dues of the year 1919 will be payable on Jan. 1, 1919, at the office of the Secretary. The clues for Members and Associates are $12 per year and the sum of. $2 additional is asked of those Members and Associates who desire to 'have the two volumes bound in the Institute's standard binding. The clues of Junior Associates are $5 per year.

Jan 12, 1918

E. E. Olcott, New York City: Prof. Kemp's valuable description of the Lancaster Gap mine is in line with many other able contributions on the origin of mineral deposits that the Institute has lately brought forward. The splendid contribution that Prof.

Jan 1, 1895

By R. G. Powell, R. Schuhmann, E. J. Michal

Liquidus surfaces in the ternary system FeO-Fe2O3-SiO2, were determined from 1250' to 1450°C by the procedure of equilibrating small samples in platinum crucibles, quenching, and microscopic examination. The experimental results were combined with previously published information to construct a ternary diagram for the system showing the entire temperature-composition range of stability of iron silicate slags. Metallurgical applications of the diagram, especially in copper smelting, are discussed briefly. IRON oxides are almost unique among the common oxide constituents of metallurgical slags in that the iron occurs in two different states of oxidation, ferrous and ferric. Moreover, in liquid slags the degree of oxidation of the iron is readily changed by reactions of the slags with oxidizing agents or reducing agents. This behavior of iron oxides in slags accounts, for example, for the effective transfer of large quantities of oxygen through slag layers in open hearth steelmaking. In this process, oxygen supplied by reactions at the gas-slag interface is dissolved in the slag with the oxidation of ferrous iron to ferric. Ferric oxide is transported across the slag layer by convection, and at the slag-metal interface the oxygen reacts with liquid metal while the ferric iron is reduced back to the ferrous state. Another group of processes in which variation in degree of oxidation of iron has great practical importance is in copper smelting. In matte smelting and converting, such large proportions of the iron are oxidized to the ferric state that problems are encountered in preventing or controlling the formation of solid magnetite. The ferrous-ferric relationship also affects the attack of iron oxides on high-SiO2 refractories, which appears to be most severe under reducing conditions for which ferrous iron predominates. Darken and Gurry' determined the chemical properties and phase equilibria of pure iron oxide slags. Their data show that iron oxide melts can have compositions ranging almost all the way from FeO to Fe2O3. The melts of lowest oxygen contents, which exist in equilibrium with metallic iron, approach ferrous oxide in composition but still have a small percentage of ferric oxide. The melts of highest oxygen contents, which have oxygen dissociation pressures of 1 atm, are above magnetite in oxygen content, with over two-thirds of the iron in the ferric state. The previously established phase diagrams for silicate slag systems all show FeO as the iron oxide component. However, Bowen and Schairer? who determined the FeO-SiO2 diagram and many of the other diagrams used by slag chemists, have been careful to point out that their systems always contained both ferrous and ferric iron. Thus, their data are for limiting mixtures with minimum contents of ferric iron, obtained by melting and equilibration in iron crucibles. Under these conditions, the Fe2O3 percentages found by analysis were small enough to justify simplification of the published phase diagrams by calculating the Fe2O3 to equivalent FeO and ignoring Fe2O3 as an additional component. On the basis of experimental measurements of melting points of iron oxides on silica in the presence of various gas mixtures, Darken3 worked out phase diagrams for the Fe-Si-0 system which show the important phase equilibria in terms of temperature and gas composition. This study clarified many aspects of the application of the phase rule to the FeO-Fe2Oa-SiO2 system and was an important basing

Jan 1, 1954

By R. R. Seeber

(Pittsburg Meeting, March, 1910.) IN the copper-mining district of northern Michigan a fair-sized mine usually operates two or more shafts along the strike of the lode, these shafts being usually at least 1,000 ft. apart. The tonnage to be hoisted from each shaft is large-from 13,000 to 25,000 tons per month. The hoisting-engines used are generally steam-driven, non-condensing, duplex engines with Corliss valves, supplied by steam from separate boiler-plants where the distance between shafts is great. In an attempt to centralize power-plants and secure central-station economies, the Winona Copper Co. installed an electric hoist of the Ilgner type, with Ward Leonard control. A brief description of this plant has already been published.1 The only point of variation from the simple Ilgner set lies in the connection of two generators to a single induction-motor by flexible couplings. These generators serve motors which operate hoisting-drums at separate shafts, viz., No. 4 shaft, Winona, and No. 1 shaft, King Philip. , The hoist for No. 4 shaft, is about 1,700 ft. from the power-plant, and in this building the motor-generator set is placed. No. 1 King Philip hoist is 1,500 ft. from the motor-generator set. The equipment of the motor-generator set is as follows: In the middle of the set is a 12-pole, 450-h-p., 600-rev. per min., 2,080-volt, three-phase, 60-cycle, variable-speed induction-motor, connected on each side to a 20-ton fly-wheel which is 10 ft. in diameter, and to a 6-pole, 170-kw, 575-volt, interpole, direct-current generator. On each side of the shaft is placed a separate exciter, which delivers current at 125 volts. The lubrication of the four main bearings that support the fly-wheels * Presented also, by mutual agreement, at the meeting of the American Institute of Electrical Engineers, New York, N. Y., Mar. 11, 1910. Engineering and Mining Journal, vol. lxxxviii., No. 3, p. 110 (July 17, 1909).

Sep 1, 1910

By G. Cartaud, F. Osmond

WE have already devoted two previous memoirs to this question. In the first we collated and discussed the existing literature on the subject; in the second, we described the crystalline forms obtained by the reduction, at different temperatures, of ferrous chloride by hydrogen or by zinc-vapor. The conclusion from these researches was that the three allotropic states of iron-a, stable below A2; 19, stable between A2 and A3; and 7, stable above A3-all crystallize in the cubic system. The differences observed were such as are customarily encountered in the crystallographic records of many minerals of which allotropic varieties or isomerides are not known, but did not conform to the ordinary definition of polymorphism. It is, however, improbable that allotropic transformations, which are placed beyond doubt by a series of positive facts, do not involve some changes in the intimate structure. As a matter of fact, the crystals we did obtain were too small to allow of a precise examination, and this might introduce an element of uncertainty in the firm establishment of our conclusions. Professor H. Le Chatelier was even led to think from some of our results that iron could very well be a rhombohedron simulating a cube, and not a true cube, and it will be remembered that the crystalline form of bismuth was for a long time incorrectly regarded as cubic. Allotropy does not, however, necessarily involve such a deduction. Without departing from the cubic system at all, a whole

Nov 1, 1906

By G. Cartaud, F. Osmond

We have already devoted two previous memoirs to this question. In the firstL we collated and discussed the existing literature on the subject; in the second: we described the crystalline forms obtained by the reduction, at different temperatures, of ferrous chloride by hydrogen or by zinc-vapor. The conclusion from these researches was that the three allo-tropic states of iron—a, stable below A2; , stable between A2 and A3; and , stable above A3—all crystallize in the cubic system. The differences observed were such as are customarily encountered in the crystallographic records of many minerals of which allotropic varieties or isomerides are not known, and did not conform to the ordinary definition of polymorphism. It is, however, improbable that allotropic transformations, which are placed beyond doubt by a series of positive facts, do not involve some changes in the intimate structure. As a matter of fact, the crystals we did obtain were too small to allow of a precise examination, and this might introduce an element of uncertainty in the firm establishment of our conclusions. Professor H. Le Chatelier mas even led to think from some of our results that r-iron could very well be a rhom-bohedron simulating a cube, and not a true cube, and it will be remembered that the crystalline form of bismuth was for a long time incorrectly regarded as cubic. Allotropy does not, however, necessarily involve such a deduction. Without departing from the cubic system at all, a whole

Jan 1, 1907

By Charles H. Kline

Industrial minerals are the Cinderella of the mining I industry. Often considered as just dirt by traditional hard-rock miners and oil drillers, these products nonetheless comprise the second largest segment of the industry and the fastest-growing one. With annual sales of $5.7 billion, industrial minerals make up 22% of the dollar value of U.S. mineral consumption. By contrast, metals account for only 11%. Fuels, of course, are dominant, representing 67%. The dollar values of production and consumption for the three segments of the industry in 1968 are shown in Table I. The growth rate of industrial minerals is shown in Table II. From 1953-1968, the current-dollar value of all U.S. mineral production increased at the average annual rate of 3.8% while that of the gross national product increased at 5.9%. Industrial minerals are the only segment of the mining industry that approached the growth of the overall economy in this period, with production values increasing 5.1% a year and apparent-consumption values 5.6% These data, expressed in current dollars, include the effects of inflation. The growth in U.S. industrial minerals production is even more striking when expressed in indexes of physical production. As shown in Table III, production of all U.S. industries increased by 4.1% a year from 1953 to 1968. The growth in production of stone and earth minerals just matched this figure. By contrast, the average annual increase for oil and gas was 2.2%: for metals, 1.6% : and for coal, only 0.6 %.

Jan 1, 1970

By Lawrence Adler

MINE hoist ropes have hitherto been selected by successive approximation, a process both tedious and inexact. The proposed expression is a readily solved synthesis of existing data and the following standard equation:' [ W + Wr + (W + Wr) -a 9 (W + W)f + b] n=T [1] For convenience, a glossary of all terms appears on page 564. Since rope weight (W,) and bending load (B) are functions of unit rope weight (Wv), which in turn is a function of rope strength (T), W, and B can be expressed in terms of T. W, as a Function of T: A study of the curve in Fig. 1, unit rope weight vs strength, yields Eq. 2: W. = -f- [2] Therefore Wr = WvL = T. [3] iv B as a Function of T: From Fig. 2, unit rope weight vs diameter, Eq. 4 is obtained: W, = 1.6d2 [4] B is related2 to d and D, and d has been expressed in terms of W, by Eq. 4, so the curve B vs W, (Fig. 3) gives Eq. 5: 177,000 177,000 This may readily be checked from the expression3 for a 6x19 rope, i.e., d3 B = 288,000D Since d2 = 0.625 W, and N = substituting d into the above expression gives Ea. 6: 180,000 180,000 B T, which will be used. [6] Into Eq. 1 substitute Eq. 3 and Eq. 6, noting that f=0.02: W + T 1.02+=T. [7]

Jan 1, 1958