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By Dr. O’Neil Thomas J., Donald W. Gentry

"We should be concerned about the future be- cause we will have to spend the rest of our lives there. " -Charles Kettering INTRODUCTION Since the early 1970s, there has been no economic phenomenon that has been more widely discussed or experienced in the United States than inflation. Al- though its precise definition and measurement are elusive, inflation has had pro- found and extensive impacts on the manner in which nearly everyone lives. It is painfully obvious to consumers that inflation is characterized by a continuing up- ward spiral of prices. In a capital-intensive industry like mining, those increases can be positively breathtaking. An interesting example is shown in Table 1. Table I shows that on a unit basis, the equivalent 1980 capital cost of Cuajone was over six times the cost of the adjacent and quite similar Toquepala operation completed in 1959. Such sobering statistics weigh heavily on the minds of executives who are contemplating major investments in new mining facilities. In spite of its monumental presence, inflation has usually been either inadequately covered or totally ignored in textbooks on engineering economy. The reasons for this are not entirely clear, but a contributing factor is the inherent difficulty in accurately predicting inflation. However, under certain conditions, inflation may become the most important factor in a mining investment, and it can rarely be safely ignored in capital investment analyses. DEFINING AND MEASURING INFLATION Defining inflation and related terms is relatively easy. Its measurement, how- ever, is the source of almost endless debate in economic and political circles. How- ever, much of that debate is not relevant to the scope of this book, so that only those issues which impact directly on the capital investment decision are covered in this section. Inflation is the general decline in the value of money as measured by what it will buy. It is clear, then, that the rate of inflation varies with the particular currency under consideration as well as the type of goods and services being purchased. One would find, for example, that the general rate of inflation relative to German marks

Jan 1, 1984

By Herbert E. Lindberg

Laboratory-scale intact and jointed rock masses were tested in field and laboratory experiments to investigate tunnel response in high stress environments. In most of the experiments the tunnels were modeled by a rigid-plastic foam polyurethane with a crush strength of 3.4 MPa (500 psi) and emphasis was placed on jointed rock parameters: joint sets (single set of parallel plane joints versus a double set of orthogonal parallel plane joints), joint plane angle with respect to the direct loading direction, and joint spacing. Other parameters were loading stress, loading direction, and tunnel reinforcement strength. Results show quantitatively the increase in tunnel deformation in jointed compared with intact rocks, double versus single joint sets, and large versus small angle between the joint plane normal and the loading direction. A surprising result was the decreases in tunnel deformation with increases in the number of joints across a tunnel diameter. The efficacy of scale modeling with laboratory-constructed rock was tested by modeling complex reinforced concrete and steel tunnel reinforcements in jointed rock masses and comparing the results with large scale tunnels previously fielded in highly jointed granite. Tunnel response was reproduced in surprising detail, including concrete fracture, steel liner bending and fracture, and critical load to produce these responses. The scale models also allowed sectioning of the jointed rock masses to observe gross sliding along the joints that accompanied tunnel failure.

Jan 1, 1982

By W. Henry Weimer

A successful surface coal operation requires the combined efforts of engineering and operating personnel. In the planning for a mine, machines should be selected to do the best work in getting the coal uncovered, loaded, and transported to the preparation plant. The best system and extent of cleaning will be determined by the market. After the fundamentals of operation have been established, the operating personnel should see they are carried out. There is no simple solution to some of the every day problems facing the operating officials. Here the production engineer with the technical approach, time studies, control methods, past experience, and available records can help in detecting causes of inefficient phases of the operations. With these studies, a careful analysis can be made in setting up the expected standards to be followed. Management can then compare the job under study with the standards and make corrections to solve the problems. 5.2-1. Annual or Daily Coal Production. Once the production cycle has been established, it is paramount that coal sales keep the productivity of the mine as high as possible. A successful company does this by what they call "the control approach." The daily tonnage report is one of the things that is a potent control tool in attaining the goals to be achieved. If production is falling short of the goal, the daily tonnage report will reveal what has to be done in the remaining days of the month or year to achieve the expected schedule. When goals are reached or exceeded, then budgeted tonnages and costs will be reached or exceeded and thus assure attainment of a profit. Failing to keep to the scheduled pace shows up quickly and prominently, facilitating any necessary action to get things back to the projected plans. The sales target is usually set a little higher than the operating production. The sales tonnage is scheduled and sales are made accordingly, slightly

Jan 1, 1968

By Stewart Murray, Philip Klapwijk

INTRODUCTION Forecasting commodity markets is like predicting winners in a horse race: to get the answers right, one needs both luck and judgement. Commodity analysts bear some resemblance to racing tipsters as they try to convince interested parties that they have an inside track on which metal is going to win the great minerals race of the 1990s. Commodity analysts share some features with the gentlemen of the turf: • They influence other people in how to spend risk capital, • They don't put their own money at risk, and • If their tips consistently fail to deliver, then they end up looking elsewhere for employment. In order to find winners we need to know about the kind of race we are in and the strengths and weaknesses of all the runners. Miners are not interested in a five furlong sprint: their race is a long distance affair -- after all, the lead-times between discovery and start-up generally approach a decade for mines that will provide the staying power which leaders require in this industry. We need to look at the environment in which our commodities will be competing: in racing parlance, the going. Our equivalent is the economic background: just as some horses are at a relative advantage when the going is soft, so some commodities will do better than others if economic growth is sluggish. If we are going to pick the winners for the late 1990s, and as an industry, make the right investment decisions, nothing is more important than being able to forecast (with at least a semblance of accuracy) how and where the world's economy is going to develop in the next decade. In addressing the question of whether minerals are going to be leaders in the 1990s, this paper considers the idea that it will increasingly be the world outside the industrialised OECD that will provide the incremental growth in demand for mineral products. Economic growth in the Developing World is fundamentally different from that in the OECD, and the pattern of demand for materials in relation to economic output is much more favourable than in the OECD. If we are to forecast the future, we need to be able to understand the past, both in the boom times of the so called Golden Sixties and in the lean years that followed them. This should help us to decide whether the future is going to be like one or other of these extremes or, on the other hand, a return to normality. Having forecast the going, we can look at individual competitors. • Which are best placed to take advantage of the economic, social and industrial trends that we can now dimly foresee? • Which can resist the continued onslaught of the new materials and technologies? • Which of them will best weather the economic storms (assuming that recessions have not yet been abolished)? If we can provide answers to these questions, we will be well on our way to picking winners, i.e., the metals and minerals that will reward their owners with growing demand, steady (and high) prices leading to profits beyond the dreams of avarice.

Jan 1, 1990

By Edward Steidle

IT has been said that "the command of nature has been put into the hands of man before he knows how to command himself," and what we see about us gives particular emphasis to this observation. If this condition be granted, the vaunted boast of school and college, of the institution that had the training of this generation, and of its fathers, and of its grandfathers, the boast that education is a "preparation for life," stands exposed as a hollow claim, or as a ghastly, cynical conception of life, or else education has fallen far short of its intentions. It has been evident for some time that education was not meeting the fullest expectations of society. In recent years there has been a deal of speculation indulged in by both laity and faculty in regard to American education and American civilization, and some few and sporadic changes have been effected. Today, however, there is no longer time for mere hypothetical considerations; we are faced with certain definite facts and confronted with obvious conditions that will not wait for fine-spun theories. If educators do not put their house in order, someone else will do it for them. The trends in mineral industries education must be in harmony with this general realignment that is today visible on the educational horizon, and only as these trends are in conformity with this movement can they be called sound. Two questions, then, confront mineral industries educators: (1) What are the trends in mineral industries education, and (2) how do these trends correlate with the major educational movements of the day?

Jan 1, 1933

By Dwight M. Lemmon

Encouraged by increased demand and higher prices for such metals as copper, lead, zinc, silver and tin, search was pressed in 1964 for mineral raw materials, especially in parts of the world that are relatively more stable politically and economically. New discoveries of metallic ores continued to be made, discoveries based on extensive geologic and geophysical work but nonetheless made in part because of good fortune.

Jan 2, 1965

By J. J. Jakosky

THE fundamental hydrodynamic principles governing the production of oil from wells have been carefully studied and evaluated by many investigators. These prior studies are quite complete and cover virtually the entire field of oil production and recovery.1 One of the most impor-tant measurements in production studies is that of the bottom-hole pressure at various rates of production.2 It is the purpose of this paper to outline the technique and economics of fluid-level measurements as applied to pumping wells and to review briefly other methods for obtain-ing bottom-hole data. The applications of bottom-hole pressure or fluid-level measure-ments are based on simple hydrodynamic principles. Under equilib-rium conditions, pbh = hd + pg + pch [ l] when pbh = bottom-hole pressure, lb. per sq. in. absolute, h = height of fluid in well, ft., d = average fluid density, lb. per sq. in. per foot, pg = weight of section of gas column 1 in. square from fluid level to casing head, pch = casing-head pressure, lb. per sq. in. absolute. In words, equation 1 states that the bottom-hole pressure is equal to the weight hd of the column of fluid plus the weight of the column of gas between the fluid and the casing head plus the casing-head pressure. At moderate rates of flow, the rate of production is approximately proportional to the difference between the reservoir, or static bottom-hole, pressure and the flowing or producing pressure; i.e.: Q = c(pr - pbh) [2] pr = the reservoir pressure, c = the constant of proportionality. However, at production rates approaching zero and also at high rates the proportionality may break down. By combining equations 1 and 2 the

Jan 1, 1939

PRODUCTION of nonmetallic mineral raw materials used by the fertilizer, ceramic, chemical, and construction industries and many others, was greater during 1953 than in any previous year. Production of fertilizer minerals was the highest in history despite somewhat decreased consumption in the second half of the year. Marketable phosphate rock production increased 10 pct to an estimated total of 13.1 million LT, valued at $78.5 million, and potash production was estimated at 1.8 million tons of K2O equivalent, valued at over $60 million. Crude gypsum output exceeded the 1952 total and approached the record of 8.66 million tons mined in 1951, with indications that 1953 will show a new all-time high. Gains and losses among gypsum products were irregular, with major gains in plate- glass and terra-cotta plasters, sanded building plasters and miscellaneous building plasters, and principal declines in base-coat plasters, prepared finishes and tile. Lath and wallboard outputs were each about 20 pct higher than in 1952.

Jan 2, 1954

By E. Gybbon Spilsbury

The recovery of gold and silver from their ores by means of the cyanide process has been so successful in the last few years that ally radical improvement would seem impossible; yet the appliance to which I wish to call attention in this paper is really a radical departure from the methods now in general use. The most modern and approved of these, known as the all-slimillg method, depends for its success on the grinding of the ore so fine that practically 90 per cent. of it will pass through a 200-mesh screen. The slimes thus produced are then agitated and aerated in tanks of various types. The main object of this treatment is to insure such a thor-

Jan 1, 1911

By James Douglas

Though liberality is not supposed to be a prominent trait of the Scottish character, Canada owes to a Scotchman, Sir Wm. Macdonald, more than to any other of its people, not only wise ideas, but pecuniary help towards extending education: and another Scotchman, in New York, has sumptuously housed under one roof three branches of the engineering fraternity, of which we are one. Having thus created us members of the same family—for the metaphorical meaning of house and kinship is identical—Mr. Carnegie expresses more emphatically than even he could in words, that, by aff'ording facilities for closest intercourse, he invites the mechanical, electrical and mining engineers to participate in the freest interchange of idea and experience, and to correlate and combine the results of their studies and activities; and, being members of the same household, to banish reserve and secrecy. And now we, the members of the American Institute of Mining Engineers, meet as though we were at home in a neighboring country. For whether we meet in Canada, in England, or elsewhere, the Institute is always received as though no political or geographical divisions separated its members from those of congenial associations in the land of its host. In truth, the title which we have assumed claims for the sphere of our activities the whole American continent, regardless of such trifling details as boundary-lines. The fact that we meet to communicate each other's experience, to discuss our difficulties, and to seek each other's aid in solving the intricate problems that so often present themselves in the course of our professional life, is an acknowledgment of our individual helplessness; and therefore an argument for united effort. But no effort can be of any value if there is an underlying suspicion

Jan 1, 1908

By Newell Alford

FORECASTS of future timber consumption in soft-coal mining are handicapped by; the lack of adequate experience records for estimating properly the timber requirements of the industry. Data were obtained from plants where records are kept or from operators who collected the information and to these were added FIG. 1.-GROWTH OF POPULATION IN UNITED STATES, FROM PEARL'S ?BIOLOGY OF DEATH." composite figures for the continental United States in 1905 and 1919 1 and for central and. Western Pennsylvania and for Illinois in 1922.2 The result, representing slightly over 928;000,000 net tons, is shown in Table 1. Some of the companies furnishing data were unable to segregate the timber into classes of use but for those who did, Table 2 shows the board feet of posts and cross bars used per ton of coal mined and the, percentage of the total timber consumed that was used in roof support. The wide variation in amounts of timber per ton of coal mined is the result of

Jan 5, 1924

By Jesse E. Wyrick

Gases and vapors are being safely stored in caverns constructed in salt formations. The storage of gas is cost competitive with other methods of gas storage and offers many advantages. Storage can be designed for high gas recovery rates and many operating caverns allow gas recovery rates in excess of 300 million cubic feet per day. Fenix & Scisson has constructed or consulted on many of these storage projects and presents some case histories beginning with the conversion of a bedded salt cavern to gas storage in 1961. Discussion includes basic considerations for storage construction, confirmation, and operation.

Jan 1, 1985

By James J. Scott, John J. Reed

In a year fraught with difficulties, especially to small operators, the more stable mining organizations have shown a dynamic readiness to plunge ahead in the development of new mines, new and ingenious equipment and new tools for management to take the guesswork out of important decisions. New Mining Equipment The mining equipment display at the American Mining Congress in San Francisco demonstrated some rather radical new design concepts and a new willingness to use imagination to come up with ingenious new applications and adaptations of standard equipment.

Jan 2, 1963

By Jack Haptonstall

INTRODUCTION The mines of western central Mexico historically contributed a profusion of gold and silver for the treasury of Spain and later provided sources for financing the Mexican War for Independence and the Mexican Revolution. The western coastal and barranca (cliff) tribes were hunters and extremely hostile, and the Spaniards were not able to penetrate many of the rich districts of their rugged homeland until the mid-1700's. This was more than 200 years after Cortez began the Inquisition by defeating the Aztecs and their allies in a decisive battle in the great city of Tenochtitlan (present day Mexico City). The Spaniards had a voracious appetite for silver and gold, and it was inevitable that they would finally subdue the natives and commence mining activities. Described in this paper are some of the precious metal mining activities in the southern half of the State of Sinaloa and the western half of the State of Durango (Figure l), and specifically those mining activities in the area controlled by the company with which the author was associated for 14 years, Minas de San Luis, S. A. de C. V., the parent company of which is now Industrias Luis Min, S. A. GENERAL DESCRIPTION Geography, Logistics and Climate The most spectacular of the physiographic provinces, the western Sierra Madre Occidental is the cliff or "barranca" province, the

Jan 1, 1983

By S. S. Deshmukh

An important element of evaluating a materials- handling system by simulation lies in being able to examine the details of the proposed operation in a fashion which closely approximates real behavior. The added factor of flexibility permits including or deleting those parts of the problem which can be shown to be important or trivial. Used carefully, simulation can match manpower and equipment far more efficiently than conventional calculations. The same is true of interacting equipment systems. This efficiency results from being able to simulate the real fluctuations in a system by using empirical probability distributions compiled from existing operations. Simulation eliminates guessing as to efficiency, absenteeism, bunching, and the broad host of delays that influence productivity and substitutes operating data in place of the usual factors. In this respect, simulation improves detail and confidence in the reliability of engineering estimates.

Jan 1, 1970

By John Hillman

Reconstruction of the British mining industry began shortly after nationalization in 1947 and continued until well into the 1950s with the support of the government. This support diminished as plentiful supplies of cheap oil from the Middle East made many coal mines uneconomic. The planned rundown which followed was foreshadowed in the 1965 White Paper which outlined financial measures to speed the closure of uneconomic collieries. The decline appeared likely to continue into the 21st century as the role of coal in UK energy requirements became less and less significant. This policy was well on course in 1973 when the oil crisis led to a complete reappraisal of the position. A government examination in 1974 of the coal industry then supported the National Coal Board's general strategy of major capital investment as set out in its ' Plan for Coal ' .1

Jan 11, 1979

By L. F. Reinartz

The furnace in which rimming steel is made has an important bearing on the quality of the steel produced. Furnace.—Particularly in the manufacture of low-carbon rimming steels, it is necessary to have an efficient, easily regulated furnace, because of the relatively high finishing temperature requirements. In recent years, the most important development in design of open-hearth furnaces has been the sealing and insulation of the greater part of the furnace to prevent air infiltration and loss of heat. Efficient, straight-line valves insure proper draft. Combustion controls guarantee correct gas-air ratios. Furnaces of all sizes ranging from 20 to 200 tons have been used successfully in the manufacture of rimming steels. Metal bath is varied from 20 to 40 in. in depth without appreciable variation in quality. Charging.—A normal open-hearth charge consists of pig iron (hot or cold), scrap of miscellaneous nature, and slag-making additions, such as limestone and burnt lime. Because of local conditions, some plants find it necessary to discard the use of pig iron and use some carbonaceolis substances with varying percentages of cast iron to replace the pig iron. It is questionable whether such practice will consistently produce the quality of rimming steel required for auto stampings and other severe drawing requirements. Pig Iron.—An open-hearth furnace under proper control should melt 150 tons of low-carbon rimming steel on about 35 to 38 per cent pig-iron charge basis. In some practices, best results are obtained when the total charge contains from 0.40 to' 0.50 per cent silicon. If reasonably low-

Jan 1, 1935

By L. F. Reinartz

The furnace in which rimming steel is made has an important bearing on the quality of the steel produced. Furnace.—Particularly in the manufacture of low-carbon rimming steels, it is necessary to have an efficient, easily regulated furnace, because of the relatively high finishing temperature requirements. In recent years, the most important development in design of open-hearth furnaces has been the sealing and insulation of the greater part of the furnace to prevent air infiltration and loss of heat. Efficient, straight-line valves insure proper draft. Combustion controls guarantee correct gas-air ratios. Furnaces of all sizes ranging from 20 to 200 tons have been used successfully in the manufacture of rimming steels. Metal bath is varied from 20 to 40 in. in depth without appreciable variation in quality. Charging.—A normal open-hearth charge consists of pig iron (hot or cold), scrap of miscellaneous nature, and slag-making additions, such as limestone and burnt lime. Because of local conditions, some plants find it necessary to discard the use of pig iron and use some carbonaceolis substances with varying percentages of cast iron to replace the pig iron. It is questionable whether such practice will consistently produce the quality of rimming steel required for auto stampings and other severe drawing requirements. Pig Iron.—An open-hearth furnace under proper control should melt 150 tons of low-carbon rimming steel on about 35 to 38 per cent pig-iron charge basis. In some practices, best results are obtained when the total charge contains from 0.40 to' 0.50 per cent silicon. If reasonably low-

Jan 1, 1935

By Elmer A. Jones

Like the caboose on the end of a long freight train L made up of mineral and metal processing and consuming industries, the mining industry progresses according to the movement of the train to which it is coupled. Sometimes the caboose rolls smoothly; occasionally it bumps along on the ties; almost always it is under criticism from someone for being too small, too large, too expensive, foolishly progressive, or hopelessly out of date. We who ride in the caboose are used to the rough by now, but it is nice now and then to have a bit of the smooth. Last year the train of industrial production rolled ahead swiftly and smoothly, and, except for a hot-box caused by strikes in copper mines, so did the caboose. As is brought out elsewhere in this issue, the outlook for 1956 is for more of the same.

Feb 1, 1956

By W. J. Keep

Almost without exception, writers on the subject say that sulphur in cast-iron will cause it to be white, and is in every way injurious. All founders believe that a small amount of sulphur in the fuel will work great damage, and that if any castings crack, or if anything out of the general run occurs, it may be charged to sulphur in the fuel. Fuel rarely contains more than 1 per cent. of sulphur, and if this can produce so marked an effect, one would suppose it an easy matter to introduce sulphur into cast-iron, so as to produce castings containing different desired percentages of sulphur. We have be-

Jan 1, 1894