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By AIME AIME

Council may deal with any matter of general interest, for which joint action of two or more of its member societies would have been appropriate, if Council had not been established. Council may initiate and carry through projects of the general character defined in the By-Laws, for which the necessary financial provision has been made. Council may take up, and in its discretion act upon, any matter of general interest referred to it by any member society or by any other society, national, state or local, or by any branch of Government, or by any individual or group of individuals.

Jan 1, 1920

By Lawrence K. Nordell

This paper reviews practices used In the selection and sizing of belt conveyors and stacker systems commonly used in crushing and grinding plant facilities. Historical and modern methods of sizing this equipment are presented. The new methods Include: 1) probability theory applications for establishing component reliability, 2) "Monte Carlo" simulation techniques used in evaluating alternative system designs and in establishing service factors and corresponding availability Indices of each system, 3) quantifying the system and component operating characteristics using computer assisted modeling tools simulating rigid body and elasto-mechanic behavior for starting and stopping large and/or complex belt conveyors.

Jan 1, 1982

By R. G. Bentsen, D. A. T. Donohue

The cyclic steam injection process has become the most widely applied and most successful thermal recovery technique in use today.1-4 Normally, steam stimulation is repeated several times during the life of a project. The problem is to select the optimum number and size of steam treatments so that the profits realized over the entire life of the project are maximum. Obviously, operating costs rise directly with the frequency and amount of steam injection. Operating efficiency, on the other hand, can be adversely affected if the amount and frequency of stimulation are insufficient. Thus arises a multistage decision problem; that is, a decision must be made at each sub-period (day, for example), as to whether steam should be injected, and, if so, how much. It is desirable that these decisions be made in such a way as to secure maximum net profit before taxes. This can be achieved by dynamic programming. To use dynamic programming, we must be able to predict not only the production rate-time curve resulting from a given stimulation, but also how changes in stimulation policy will affect this curve. In this study, the effect of steam injection on well performance is estimated on the basis of a simple model that takes into account both steady-state and transient flow. Oil production rate is calculated for both types of flow, and the larger of the two values is used. This allows the calculation to change to radial steady-state flow at such time as this mechanism becomes more effective than the transient mechanism. We propose to show how dynamic programming can be used to optimize the steam soak process with respect to net profit. For this, a mathematical representation of the steam soak technique is necessary. A further objective, therefore, is the formulation of a mathematical model capable of realistically simulating the physical process. Oil Production Response Model The advantage of using a mathematical model is its generality and ease of manipulation. However, the model must be an accurate representation of the physical process, for a solution derived from a model can be no better than the model itself. The question now arises as to how well the model should be expected to simulate reality. In general, the simplest model should be tried first, for additional accuracy is apt to require additional cost and time. Also, the search for a high degree of accuracy may yield only greater complexity and difficulty without yielding significantly better results. With this in mind, we kept our model as simple as possible, yet generally representative of the actual physical process. The number of state variables is limited to three, and stochastic variations in the parameters are ignored. As a consequence, use of this model should be restricted to cases in which the underlying assumptions are not severely violated. In

Jan 1, 1970

By Charles Will Wright

MINERAL production in almost all European countries suffered a sharp setback because of the war. Plants were damaged, transportation facilities disrupted, and labor dispersed and demoralized. Since the war, due to lack of confidence and economic stability, there has been little incentive to rebuild and expand the mineral industries even though a big demand at high prices exists for mineral products. Most mining and metallurgical companies in Europe hesitate to invest their capital because of the tendency towards nationalizing industry, high taxes, and low output of labor, as well as the deficiency of mine supplies and equipment within their countries. In short, they do not have faith in the future, and for these same reasons and fears most of the mining companies in America will not risk capital investment in Europe. In Europe, including the United Kingdom, free enterprise has been losing ground and as a result the foundation of their economic welfare is being undermined. American mining interests willing to take the initiative could help in counteracting this influence if a way were found for them to co-operate with the European producer without too great a risk.

Jan 1, 1948

By Gieskieng, D. H.

Published tables of jaw crusher capacities are compiled for the most part from field performance data, interspersed with interpolations, extrapolations, various safety factors, and other modifications. Such a table attempts to balance and equalize field data from widely different materials, with differences of crushability, efficiency of feeding, sizing of the feed, and so on. The tests described in this paper were undertaken with the objectives of checking previously reported capacities; of studying the effects of various factors upon the capacity, including jaw plate curvature; and, if possible, of deriving a general capacity equation. Such an equation has been derived from the data obtained in these tests. It is given together with factors for its use. While more accuracy than is usually required may be obtained by careful application of the equation, it is of simple form and provides a convenient reference plane upon which the potential capacity of various crushers may be compared, and with which operating adjustments may be made on existing installations. The principal deviation in these tests from the usual approach consists of a laboratory technique which has been developed for the production of selected

Jan 1, 1949

By F. W. Bradley

GOLD is a large subject. One could talk about its geological or mineralogical occurrences, prospect- i11.g for it, mining of .it, its metallurgy or its marketing; but I have decided to limit my discussion to gold as a business-that is, to its production and marketing. In the production of gold, it is necessary to consider the many possible sources, the quantities available, the capital and operating costs and the chances of price-breaking competition. So in the following remarks I shall endeavour to point out that though gold is found in every formation constituting the earth's crust, though it is possible to-find it free in great concentrated placer deposits on the surface, though there are still large unprospected areas of both the surface and the crust, though it may be possible to produce it by the cheapest labor on earth, and by processes not as yet developed, it still has an unlimited market at a definite price. There is no reasonable fear of disturbance by the finding of bountiful deposits, or by cheapening the cost of production due to devaluation, or by the development of any easy processes for direct, or for by product, production.

Jan 1, 1932

By R. E. Allen

THERE was once a time when a practical oil man would appraise or buy a producing property on the basis of from $200 to $500 per barrel of average daily settled production. Curtailment-has, for the present at least, caused a virtual abandonment of the "barrel -of settled production" as a yardstick of, oil property value and in its place has come the "barrel of allowable production," which, although an artificial thing, is nevertheless now the principal factor governing the rate of ?pay out? or investment return. The potential production of a well, settled or otherwise, is of less importance in determining the present worth of a well than is the rate at which it may be produced. Speaking only of true potential for the moment, it is obvious that of two similar wells having the same potential, the one having the highest rate of allowable production would be worth proportionately more than the one of lesser allowable. The discount factor for deferred return and risk can easily vary the present values of the two wells by as much as 20 per cent when allowable rates are not greatly different.

Jan 1, 1934

By Robert Glass Cleland

DURING the closing month of 1929, Walter Douglas found his health impaired by the strain of many difficult years of alternating prosperity and depression, and in April 1930 resigned the presidency of Phelps Dodge. Douglas was succeeded by Louis S. Cates. The choice broke a tradition that had been held inviolate for almost a hundred years. For the first time in its long history, the direction of the company's policies and operations was entrusted to a stranger without previous Phelps Dodge background, training, experience, or tradition. But the choice was wisely made. For a time at least, the path of Phelps Dodge was to run through rough and dubious ground, and no man in the United States was better qualified to blaze that trail than Louis Cates. After graduating from the Massachusetts Institute of Technology, Cates had served a rough and financially un- profitable apprenticeship at one of the century-old mining camps of Chihuahua, Mexico. Following his return to the United States and a brief interlude as assistant to the president of the National Steel and Wire Company, he had resumed his mining career, first as timekeeper, then as

Jan 1, 1952

By W. L. Zeigler

THE year 1930 in the Ceur d? Alene district was one of curtailment in production. Many of the small properties were closed entirely and only three large. producers, the Bunker Hill & Sullivan, Hecla, and the Morning mines were left producing at capacity. No innovations in milling were evident, but progress was made in reducing costs as is always necessary in times of low metal prices. One new concentrator was constructed, a 500-ton daily capacity selective flotation plant for, the Jack Waite Mining Co. This mill uses coarse crushing, followed by hand sorting, for both a high-grade ship- ping ore and waste. The remainder of the ore leaving the sorting belt is crushed in a new type Traylor reduction crusher to %-in. size and stored in large capacity mill ore-bins. The grinding is done with ball mills, in closed circuit with a Dorr classifier to 75 per cent - 200 mesh. Minerals Separation 24-in. flotation machines are used both for a lead and a zinc concentrate, with double cleaning in each case. The concentrates are dewatered in Dorr thickeners and filtered on Oliver late-type filters.

Jan 1, 1931

By C. M. Smith

PILOTED by Cadwallader, Evans, Jr., as chairman, the Coal Division got under way Monday morning for the first of three consecutive sessions. N. F. Patton started the ball rolling with a paper on the economics of anthracite distribution, which was ably discussed by H. J. Rose, W. S. Blauvelt, and others. Mr. Patton pointed out many incongruities in freight rates, dealers' margins, and other factors which are disturbing the distribution of anthracite, one result being that trucks are hauling at least six million tons of anthracite annually, half of which is stolen. In the discussion of the papers the desirability of greater uniformity in the production and shipment of coal from month to month was urged; with larger summer price concessions as a means toward this end. "Performance Expectancy of Domestic Underfeed Stokers for Anthracite," by Allen J. Johnson, brought this important platter down to date by showing the range in capacities and efficiencies to be expected from well-made stokers, and by detailing other of their operating characteristics. One of his most interesting points is that the efficiency of domestic stokers is practically equal to that of handfiring for good installations and operations of both

Jan 1, 1935

By U. C. Tainton

THE world-wide continuation of low prices for zinc in 1934 has militated against any striking changes in the position of the metal. The price of zinc in London at the end of the year, about £11 5/8 per long ton, or 2.5c per pound at the existing rate of exchange, is more than 25 per cent below the average price for last year. In these circumstances probably the most significant event of the year was the putting into operation of the new electrolytic plant of the Giesches company at Magdeburg, Germany. This plant is designed to have an initial capacity of 20,000 long tons per year, and it is planned to increase this to 40,000 tons annually. This development is significant not only as indicating a continued swing of zinc metallurgy towards electrolytic methods, but also because it will make Germany virtually independent of foreign sources of zinc. This will mean that the zinc tonnage normally exported to Germany from Belgium and Poland will. become available for other markets, and it is feared may lead to lower prices unless the production of Bel-

Jan 1, 1935

By AIME AIME

ADDRESSING the Ohio Section at a recent meeting in Columbus, Ohio, R. C. Allen, executive vice-president for Oglebay, Norton & Co., Cleveland, spoke on "The Iron-Ore Industry of the Lake Superior Region in Prosperity and Depression." The speaker considered this region in connection with the problem of national security. This is the age of minerals; progress depends on them; and next to agriculture, the mineral industry is of prime importance. The United States has no shortage of minerals rather an over-supply; but many mines have been and are being exhausted. The shifting of the sources of supplies of minerals so important as copper, petroleum, and iron to other countries would create internal strains and affect international relations. There will be no early decline of ore mining in the Lake Superior region unless it is forced by unwise public policies. Iron ore is industrial strength and self-sufficiency. A study of economic geography is important for statesmen and mining men, because the minerals essential for peace and war are haphazardly or irregularly distributed throughout the world. Of these minerals, 75 per cent are owned by 10 per cent of the population, mainly peoples of Anglo-Saxon origin.

Jan 1, 1934

By GUY C. RIDDELL

THE recent purchase by an American investment trust of a substantial block of shares in a British owned Venezuelan copper operation directs attention to mining activities that have been quietly gaining momentum in that country for a number of years. We hear so much of oil work in Venezuela that attention to its metal-mining activities is in most quarters casual. In gold and copper the country has made some interesting mining records, and two of the old districts are ,digging in for a come-back. Copper Copper production centers in the state of Yaracuy. The Aroa-Cumaragua mining region has had a long and eventful history. The Aroa mine itself, 50 miles from the coast in West-Central Venezuela, was discovered in 1605. First mined in 1632, owned at one time by Simon Bolivar, it has been reopened many times and is now , the basis of substantial operations by the South American Copper Syndicate, Ltd. of London. The latter has operated the property profitably, off and on, for a number of years, paying heavy dividends on a small investment-at times over 300 per cent annually.

Jan 1, 1929

By Schumacher, Earle E.

THE solidus line above the solid solution field in the lead-antimony system was originally determined by Dean and his associates1 from heating curves. They did not regard this line as having been accurately fixed and in their more recent publications2 the curves drawn do not follow closely the original data. The precise location of the solidus line is of importance in the extrusion of lead-antimony cable sheath, as the temperature of the metal in this process must be less than the lowest temperature at which any part of the alloy in the lead-press charge becomes liquid. It is very desirable, however, to operate at as high a temperature as possible, as the rate of extrusion for a given pressure is approximately doubled for an increase of 10" C. in temperature. The precise location of this line is also important in the investigation of ternary systems of lead, antimony and a third metal. For these reasons, and because of the differences reported in the literature, data were secured on the lead-antimony solidus line by the classical quenching-test procedure.

Jan 1, 1927

By Edward H. Bzirdick

THE territory under particular consideration in this article comprises portions of La Plata and Montezuma Counties, situated in the southwestern corner of Colorado, and around the base of the La Plata Mountains. (See Fig. 1.) In southeastern Utah and northeastern Arizona there are several mountain systems whose origin and structure are practically identical with the La Platas so that ore occurrences found in the latter can be hopefully looked for in the former. With this assumption, there is an area around the laccolithic ranges which offers promise for a successful exploration for gold ores. Ore occurrences of the Silverton, Telluride, Rico, or Ouray Districts will not be discussed, although in these areas the Mesozoic sediments are more or less involved within the ore-bearing complex. These have been intensively studied and developed. The idea is to set forth what my mining experience has been within the largely unaltered . Mesozoic horizon which remains around the extreme bases of the La Plazas. This, until recent years, has been almost entirely neglected by prospectors and operators and, so far as similar territory in Utah and Arizona is concerned, so remains.

Jan 1, 1934

By G. S. Anderson

PRIOR to 1912 the only rail outlets for a large part of the coal regions of Carbon and Emery Counties. Utah, were over single-track lines of the Southern Utah R.R. and Castle Valley Ry. Companies, forming a route extending from Mohrland and Hiawatha, Utah, to a point of connection at Price, Utah, with what is now The Denver and Rio Grande Western R.R. Co. These two tap lines were poorly and inadequately constructed, with impracticable grades, lacking in equipment, and incapable of being put into condition to serve this region and handle the output of the mines, to say nothing of making possible increased production and new development. Any plans for the new development and increased output necessarily involved new and adequate railroad service. It was essential, not only that additional facilities be provided but that these facilities be in the form of an efficient and up-to-date railroad providing an independent through operation from the coal mines to a point of direct connection with the lines over which the product would be distributed to consumers. For this purpose, the Utah Railway Co. was incorporated in

Jan 1, 1948

By AIME AIME

THE Chairman of the Iron and Steel Division for 1945 is one of the most versatile and best-known men in this industry, with wide experience in research and operations and in handling both the men and the materials that are used in enormous quantities. Erle G. (Doe) Hill was born in Santa Ana, (alit, April 21, 1890 and graduated (Bachelor of Science) in mining and metallurgy from the University of California in 1913. For the next five years lie held a variety of jobs as miner, foreman, and null superintendent in gold, silver, copper, and quicksilver mines in the West and in Mexico. As Doe was an individual endowed with an exceptional amount of horse sense, he left the West in 1918, to become instructor of mining engineering and ore dressing at Carnegie Institute of Technology, and while in that post did considerable consulting work as a geologist and mining engineer. In 1920, still possessing the same common sense. he got out of mining engineering and geology and became associate professor of metallurgy at the University of Pittsburgh, a position he retained for nearly ten years.

Jan 1, 1945

COLORADO SCHOOL OF MINES On February 21, 1918, the students of the Colorado School of Mines who are members or have applied for membership in the Institute re-organized the "Scientific Society of The Colorado School of Mines,? which has for its .purpose the study and discussion of mining problems. Its meetings will be held on the first and third Wednesdays of each month, in Guggenheim Hall. Following are the officers R. W. GIBSON, President, W. A. CONLEY, Vice-president, F. L. SERVISS, Sec'y.-Treas. At present there are 62 members, seven of whom are Faculty members. F. L. SERVISS, Secretary.

Jan 5, 1918

By ME ME

IT just so happens that we do our best thinking while painting wood- work and last Saturday while finishing up the screens (the bugs come late where we live) the paint very nearly ran out. By adding turpentine, it just stretched. It was pretty thin for the job though, which made us think that that is just about what the situation is going to be in the mining industry if something isn't done to increase the number of enrollments in engineering curricula. Engineers are going to be spread too thin for the job at hand.

Jan 8, 1951

The John Fritz Medal for the year 1917 has been awarded to Professor Henry Marion Howe for his investigations in metallurgy, especially in the metallography of iron and steel. Record of the John Fritz Medal. The John Fritz Medal Board of Award has published a book giving a history of the Medal, the Rules of Award, biographical notices of the medallists illustrated with portraits, etc. This beautiful book, designed, engraved and printed by Bartlett Orr Press, New York, may be obtained by addressing the Secretary of John Fritz Medal Board of Award, Engineering Societies' Building, New York. Price $3 per copy.

Jan 3, 1917