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By Edward Sayre

IN shaft sinking for coal mines, the cost item greatly influences the method adopted. This holds true especially when soft material must be traversed. The average life of a coal mine is short. This is clue either to the limited area of the coal basin or to the great expense of maintenance and haulage underground when the entries are extended a considerable distance from the hoisting shaft. Therefore, the engineer in opening a coal mine is confronted with the fact that the cost must be kept within certain bounds else the venture will prove unprofitable. For this reason he may be prohibited from adopting certain safe, but expensive, methods that are used in sinking caissons for foundations, driving transportation tunnels, or other work of permanent construction. A common method of sinking through difficult ground employs the aid of a steel shoe pushed ahead of the shaft timbers. Another is the drop-shaft method. These two methods were used in sinking the main shaft and the air shaft of the Eagle No. 3 mine, at Des Moines, Ia., and the following data show the relative success and cost of the two methods of sinking under the same conditions. A drill log of the material to be penetrated was as follows (see Plate 1, Fig. .1)

Jan 9, 1916

By Herman Poole

When finely divided ferrous sulphide, FeS, is roasted at a moderate, carefully-regulated temperature, the iron and sulphur are oxidized, the first products being probably ferrous oxide and sulphurous acid. In the presence of oxygen of the air the ferrous oxide soon becomes ferric oxide, and, in the presence of oxygen and the ferric oxide, the sulphurous acid oxidizes to sulphuric acid. These facts are well known, having been established by Plattner many years ago. As a further reaction, some of the sulphuric acid parts with a portion of its oxygen to oxidize more ferrous oxide to ferric oxide, and a portion of it escapes uncombined, or else unites with the iron oxides to form sulphates. Ferrous sulphate is usually soon oxidized to ferric sulphate, and if the heat becomes sufficient, this is then decomposed into sulphuric acid and ferric oxide. As a result of these reactions a mass of more or less pure ferric oxide is formed which is generally made porous by the escaping gases and, if rabbled properly, practically all the sulphur is expelled. If ferric sulphide or ordinary pyrites, FeS2, is roasted, a portion of the sulphur sublimes and usually burns to form sulphurous or sulphuric acid, although at times and under favorable conditions, some of the sulphur is driven off uncombined, and can be collected as such. Under ordinary methods of roasting, however, only a small portion escapes combustion. By the combustion of the sulphur an increase of heat is developed and, as a consequence, the reactions mentioned take place more rapidly and actively,—more sulphuric acid is formed and the oxidation is more complete—nearly all the iron being left as ferric oxide with practically no sulphate or ferrous oxide. When the iron sulphide is in lumps the roasting proceeds generally as with fines, but with some changes due to mass. The

Jan 1, 1906

The committee appointed .by W. R. Ingalls, president of the Mining and Metallurgical Society of America, to nominate candidates for the' annual gold medal of the Society consisted of E. G. Spilsbury, J. E. Johnson, Jr., and Bradley Stoughton. This committee recommended Mr. Schneider of the Creuzot Works in France for achievements in ferrous metallurgy, which recommendation was approved by the Society. From the report of the committee, the following facts relative to Mr. Schneider's career are taken: Born in 1868, Charles Eugene Schneider undertook the management of the Schneider establishment in 1898, after the death of his father, Henri Schneider. Under his enlightened management, the Schneider establishments have been considerably extended, their activity being not only directed to increasing production, but also to spreading more and more their scope for action in all branches of industry-in metallurgy, mechanical and electrical construction, shipbuilding, artillery and ammunition, and in public works. During the 10 years preceding the war, the number of employees in these establishments, and without counting those of the more numerous subsidiaries, increased approximately 50 per cent. While giving to peace industries all the attention necessitated by the progress in science and the continual improvement in industrial methods and products, Eugene Schneider, with a perspicacity that recent events have justified in a striking manner, especially directed his

Jan 3, 1919

By James K. Grunig

As the real price of uranium increases, deposits of lower and lower grade will be treated. The various occurrences of uranium ore are described and the chemical aspects of extraction are detailed.

Jan 1, 1981

By N. J. Feola, E. P. Klier

NOTCH properties of titanium materials have been extensively investigated in the impact test.'-" For the most part the impact strength meas- ured suggests a ductile-brittle transition that lies at relatively high temperatures, thus indicating a possible notch sensitive condition at ambient temperatures. Recently it has been shown' that the impact strength for unalloyed titanium, as for aluminum alloys, may be a nonsensitive index of notch sensitivity as provided by the notch strength as measured in the notch tensile test. The notch strength for unalloyed titanium was found to depend on the nitrogen and carbon contamination levels. In the present work the levels to which oxygen, nitrogen, and carbon contaminants can be tolerated without leading to excessive em-

Jan 1, 1958

By R. C. Allen

About four years ago the writer proposed a revision of the correlation of the Huronian formations in Michigan, and noted the bearing of the question on the correlations of the Huronian rocks in Wisconsin and Minnesota.1 Dr. C. K. Leith opposed this revision and argued for the retention of the correlations of the United States Geological Survey, published in 1911,2 for which he and Dr. Van Hise were mainly responsible. As late as June, 1917, Harder and Johnson, following Leith, thought it "premature to change radically a correlation based on years of careful field work."3 The work of Wolff on the Mesabi and Cuyuna Ranges, of Hotchkiss on the Gogebic Range (unpublished), and of the writer and assistants on the Michigan ranges, together with data developed by exploratory and mining operations, has introduced so many new facts not recognized in the scheme of the U. S. Geological Survey that the correlations of 1911 must be considered, in some important respects, obsolete. Indeed, new data are accumulating so rapidly that any classification, which for the moment may seem best to explain the facts, is almost immediately modified or refined by further observations. The problem of Huronian correlations is difficult, but interesting and important. With the aid of fossils, stratigraphers of the post-Algonkian formations have been able to show that slight disconformities mag separate strata of vastly different ages, and that within physically conformable strata may be concealed a hiatus of great magnitude. In the non-fossiliferous Huronian group, minor physical breaks in the strata are only beginning to attract attention, and it is too early to discuss what bearing these will have in correlating the formations of one area with those of another, but it is safe to say that the "lost intervals" which are not disclosed by physical relationships will remain forever lost; therefore we may not hope to discover the ultimate truth concerning the

Jan 1, 1920

By Thomas Fraser

BECAUSE of the present interest in the subject of sulfur in coal and its removal, such information as is available in the coal-washing literature on the various factors that determine the adaptability of a coal for wash- FIG. I.-COAL-WASHING TABLES OF ONE-FOURTH COMMERCIAL SIZE. ing have been collected and are presented here together with some observations based on results of experimental work carried out in the coal-washing laboratory of the mining department of the University of Illinois, and investigative work at Illinois washeries in connection with the work on reduction of the sulfur content of coal, being carried on at the Urbana Station of the.U. S. Bureau of mines. This investigative

Jan 9, 1919

By R. J. Wensley

The use of small substations for the supplying of 275-volt energy to the locomotive and cutting machines in coal mines is a well-established practice. A few years ago, when labor costs were lower, these substations were located as near to the load as possible, and an operator was provided for each station. This practice has now become so expensive that substations are being located with reference to other mining machinery, such as hoists or pumps, so that one operator can look after both. Sometimes the substation is operated by one whose duties make him traverse quite a large area. In such cases the interruption of alternating-current supply may produce a long interruption in the direct current, as the station cannot resume service until this man reaches it. Such interruptions interfere seriously with production and may easily counterbalance the supposed saving gained by such operating methods. The grouping of substations for convenience in operating may also result in excessive copper loss and consequently poor trolley voltage, with its attendant evils of low locomotive speeds and increased locomotive motor maintenance. The speed of the coal-cutting machines will also be reduced. By relieving the substation of its burden of the operating labor cost, the most economical location, from an electrical standpoint, may be chosen. The matter of machine insurance should also be considered. If an attendant is caring for several kinds of equipment, he cannot watch the machine continually for signs of trouble; therefore, continued overload, phase failure, low alternating-current voltage, bearing trouble, etc. may result. Some partly automatic equipments have been installed; these have protection against low voltage, reverse current, and bearing trouble and are provided with automatic reclosing circuit breakers. This is a step in the right direction but it does not go far enough to give first-class machine insurance. The saving in maintenance costs is often the smallest item, when considering the automatic substation as machine insurance. When the coils in a machine are roasted out, due to continued overload or to opera-

Jan 1, 1922

By E. F. Sturcken, J. W. Croach

A grain orientation distribution function, P(u,F), was developed for use in predicting physical properties in oriented metals. Examples are given of the use of the function to predict thermal expansion coefficients in rolled uranium rods and plate. The P(u,F) function was synthesized from X-ray difpaction intensity measurements, Ii, norrnally used to plot inverse pole figures. The symbols u and F specify the angles that the crystallographic axes of the grain make with the normal to the sample surface and P(u, F) gives the number of grains oriented in each direction, (u,F). P(u,F) is obtained from a least squares fit of the Ii to an orthonormal set of spherical harmonic functions. The P(u, F) function was also used to define a quantity, J, which is a measure of the departure of the orientation distribution from unifomzity (or "randomness"). The J parameter may be used to follow, quantitatively, the amount of preferred orientation induced as a function of mechanical working or heat treatment. An example is given of the application of the J parameter to prefevred orientation studies of hot- and cold-rolled uranium rods and hot-rolled uranium plate. Because P(u,F) is derived from relative intensity measurements by the powder diffraction technique, it is applicable to material with large absorption coefficients and/or grain size and is particularly suitable for characterizing the preferred orientation of large numbers of samples such as fuel elenzents for a nuclear reactor. IN general the physical properties of an oriented metal depend on the direction in which the properties are measured. Hence to predict physical properties the grain orientation must be known as a function of the direction of the specimen. The conventional methods of expressing preferred orientation measurements are the pole figure1 and the inverse pole figure.2-8 Both methods are difficult to use for predicting physical propertiess because they are graphical and because they are stereographic projections and hence are not "area-true." In the present report a quantitative orientation distribution function, P(u,F), is synthesized from pole density measurements normally used to plot inverse pole figures. For inverse pole figure plots the pole densities, pi, are obtained by powder dif-fractometer intensity measurements of their reflections from a flat surface of the sample, normal to the direction of interest. Each pole density, pi, represents a single orientation, i, and is proportional to the volume of material with orientation, i; hence a set of pi gives an approximation for the general orientation for the sample direction measured. The expression8'7 for calculating the pole densities, pi, from the diffraction measurements was previously

Jan 1, 1963

By Valentine Garfias

THE various phases of the Mexican oil industry have received so much publicity that there is little to add to the discussion of present and future production, extent and importance of prospective fields, and status of petroleum legislation, to mention but a few of the angles of the Mexican oil problem. However, out of this wealth of information, which is generally of contradictory nature, the average petroleum man is at a loss to know something definite regarding the various questions involved so, keeping the foregoing in mind, it has been the writer's aim to record in a concise form the most reliable and up-to-date information regarding the salient features of the Mexican oil situation. PRESENT STATUS OF MEXICAN OIL INDUSTRY Production During 1921 The Mexican oil fields, during 1921, produced in round numbers 203,000,000 bbl. of which 176,000,000 bbl., or 86 per cent., were exported, the bulk of -these exports, or about 73.3 per cent., going to the United States. The Mexican exports were divided by grades as follows: Light crude, 47.0 per cent.; heavy crude, 22.0 per cent.; tops, 3.5 per cent.; fuel oil from light crude, 24.0 per cent. The balance, or 3 1/2 per cent., includes the bunker fuel shipments and the coastwise trade in Mexico, which is not classified as to grades. The figures show that, in importance, the light-oil fields from about 755 per cent. of the Mexican petroleum industry.

Jan 4, 1922

R. S. MACPHERRAN,* Milwaukee, Wis. (written discussion?);-Mr. Stork's paper is very interesting, but I am unable to agree with some of his conclusions. He argues very strongly for the beneficial effect of oxygen, but gives no actual determinations of this element to support -his views. He states that the oxygen resulting from a high bed, heavy charges, low coke ratio, etc. must not be confused with the oxygen under normal conditions. I will be glad to know in what respect these oxygens differ or in what state they occur. Is it his opinion that the beneficial type is present as a dissolved gas and the other as metallic oxide? I will not discuss the first five of his six points, as I have not seen enough trustworthy determinations of oxygen in cast iron to form any conclusions as to its effect. I have never known the addition of manga-nese, however, to reduce the strength of cast iron. Under the sixth point, I would say that the addition of steel lowers the total carbon content, and by this action will increase the strength independently of oxygen. This reduction of carbon operates also to raise the melting point. It is interesting to note here that the author, in order to get proper fluidity for his cylinders, was obliged to reduce his oxygen by raising the manganese in the charge.

Jan 12, 1919

By William Fink

ZINC is one of the effective elements introduced to enhance the strength of aluminum. This strengthening is principally attributable to the high solid solubility of zinc in aluminum and the pronounced variation of solubility with temperature. Consequently an accurate determination of the solid solubility curve is desirable. The solid solubility relations have been studied by numerous investigators. Shepherd' first established the existence of a solid solution region at the aluminum end of the diagram (y phase) by specific volume and microscopic determinations. Bauer and Vogel2 published a constitutional diagram which showed the limits of solid solubility as determined by thermal and microscopic methods. Hanson and Gayler3 presented the aluminum-zinc diagram which is now most generally accepted (Fig. 1). Chill-cast samples were given thermal treatments designed to obtain equilibrium conditions, quenched, and microscopically examined.. The solubility was placed between 15 to 20 per cent at 600 C., 20 to 22 per cent at 140° C. and 36 to 38 per cent at 270° C. Sander and Meissner4 decidedly modified the limits of they phase field of Hanson and Gayler's diagram by using similar methods on chill-cast specimens annealed for a shorter period of time. Tanabe,5 utilizing dynamic hardness, electrical conductivity and dilatometric measurements of specimens at temperature, obtained values comparable to Hanson and Gayler's at room temperature, but appreciably lower at higher temperatures. Nishimura6 concluded from age-hardening results of aluminum-zinc alloy chill castings, which had been quenched from 400° to 500° C., that the solubility of zinc in aluminum at room temperature is less than 5

Jan 1, 1932

By D. M. Bondurant

Auger mining-extraction of coal with large diameter augers is proving profitable in recovering coal left after stripping has ceased to be economical. Its many advantages-low initial cost of equipment, low operating cost, low power demand, adaptability to selective mining, simplicity of operation, etc.-have excited the interest of some in the industry in its possibilities for underground operation.

Jan 5, 1951

By John V. Beall

Many Americans will judge the energy crisis by the picture shrink on their TV screen. And they are right to make this assessment considering the large areas of the country with marginal generating capacity, (See Fig, 1). The Federal Power Commission (FPC) recommends 20-25% reserve generating capacity above peak summer loads and 15-20% as minimal. The New York metropolitan area is the most concentrated power service area in the United States, and a spot check with Consolidated Edison, serving this area, revealed that on Friday, August 18, the company was operating at 5% reserve.

Jan 10, 1972

By A. F. Bertuzzi, M. R. Tek, F. H. Poettmann

A method is presented for predicting pressure drop for two-phase fluid flow in horizontal pipes. A set of 267 experimental measurements randomly sampled from approximately 1,000 measurements from various literature sources was used. Pressure gradients calculated by the procedure developed and compared with the experimental values showed a bias of +0.82 per cent and a standard deviation of 20.8 per cent. The advantatges of this method over other available methods of predicting two-phase flow pressure drop are (a) its comparative simplicity of application, (b) its relative independence of flow patterns, (c) its accuracy, which on the basis of a statistical evaluation predicts pressure drop closer than other available methods, and, (d) its ability to satisfactorily correlate laboratory data from various sources while the correlations from these sources do not appear to agree with one another. The method has been reduced to a simplified graphical procedure, suitable for field use. A two-phase f factor is defined and correlated with parameters involving the flowing gas-liquid mass ratio, a Reynolds number for the gas phase, and a Reynolds number for the liquid phase. The choice of parameters allows the correlation to reduce to the usual f factor plot for the limiting conditions of (111 gas or all liquid. INTRODUCTION The mechanics and characteristics of two-phase flow systems have been of interest throughout the industry for some time. In numerous engineering installations such as pipe lines, chemical reactors, and heat exchangers, two-phase flow conditions are of every day occurrence. In oil production operations it has been desirable, in some cases, to consider transporting gas and oil together in a common pipe from oil field to process plant. The trend toward centrally located stock tank batteries in oil fields has resulted in longer gathering pipelines in which more than one fluid phase is flowing. The increase in the producing capacity of oil wells due to new production tech- niques has created the need for review and re-design of many surface gathering lines for properly handling the increased production. Optimum pipe size for the situations described above has become an important factor. The problem which is of interest here involves the ability to predict the relationship between pressure drop, fluid properties, fluid rates, pipe diameter, and pipe length. Although the literature1,5,10,13,18,19 contains various articles dealing with specific cases of the problem, Lock-hart and Martinelli17 proposed the most general solution. Their method has been later modified by Baker:1 Alves2 demonstrated that different flow patterns are possible for a flow mechanism defined by Martinelli such as gas turbulent, liquid turbulent. Baker explained deviations experienced with Martinelli's correlations on the basis that different flow patterns could exist for the same flow mechanism. Using Martinelli's method of correlatioil, Baker correlated data for each flow pattern for the turbulent-turbulent flow mechanism. Bergelin and Gazley6,7 presented a correlation for predicting gas phase

Jan 1, 1957

Mining Methods J. HURRAY RIDDELL,Chariman Guy N. BJORGE, Vice- Chairnan ROLAND D. BANKS, Secretary Alluvial Mining CLINTON BERNARD O. B. PERRY BENERE H. GRANT C. M. ROMANOWITZ Open-Cut Mining Iron G. E. DIERL P. G. HARRISON EARL E. HUNNER

Jan 1, 1939

By C. G. Rhodes

A technique for producing etch pits in uranium monocarbide has been developed. The pits, which are assumed to be associated with dislocations, appear individually and as arrays delineating sub-boundaries, as seen in Fig. 1. The samples used were single crystals prepared by the technique described by Nadler.* Uranium

Jan 1, 1963

By A. Lee Barrett

AN accelerated trend toward mechanical mining was noted in 1940, calling for improvements in and better performance of transportation, hoisting, and ventilating equipment. One of the most interesting experi¬ments in transportation is the track shuttle-car operation first put into use by the Princeton Mining Co. in Indiana and later at the Montour 4 mine of the Pittsburgh Coal Co. This system is based on the use of 10-ton drop-bottom mine cars operating on track and han¬dled by an ordinary gathering loco¬motive. These mine cars are loaded and taken in trips of two to a central dumping station which serves four or less loading machines. The dumping station consists of two standard chain-and-flight room conveyors, approximately 50 ft. long placed side by side approximately 4 ft. below the track from which the drop-bottom cars are dumped. These conveyors are operated at low speed and discharge into two similar elevating conveyors which operate at a higher speed and convey the coal to a trip of standard mine cars. A dumping station is usually located so that approximately 500,000 tons of coal may be handled through it before a move is required. This plan appears to have considerable possibilities for the mine equipped with small mine cars and standard locomotives since the advantages of large mine cars can be secured at a fraction of the cost required to install such cars throughout the mine. It appears logical that the future will see a much wider use of this modification in transportation.

Jan 1, 1941

By T. L. Kesler

With only six small spodumene prospect pits, no detailed mapping, and no subsurface information in 1938, the Carolina lithium-pegmatite area now contains four mines among more than 25 properties on which exploratory work has been done. Even the open pit mine of Foote Mineral Co. described herein, from which ten million tons of ore and waste have been removed since 1952, was virgin ground when mapped in 1938-40 1. It has been a privilege to participate in the transition. In 1940, the spodumene pegmatites were known in a 25-mile belt (originally noted for tin prospecting) between Lincolnton, N. C. and Grover at the South Carolina line. Subsequently, Broadhurst 2 reported relatively small bodies northeast of Lincolnton near the Catawba County line. To the south, diamond drilling done in 1953 on the old Ross tin-mine property near Gaffney yielded pegmatite cores containing a few crystals of spodumene. This fact, not previously reported, suggests that some of the pyroxene in the Ross shaft as described by Sloan 3 may be spodumene.

Jan 9, 1961

By Albert F. J. Bordeaux

The immediate vicinity of the sea-shore, affording special facility for the exportation of ores, makes it possible to work certain mines in the Vladivostok district, which, in more remote places of Siberia., would remain unproductive. Outside of the city of Vladivostok the population is small and the country is very little prospected. Additional discoveries of valuable deposits like the large body of calamine which has recently been opened in the neighborhood of earlier worked lead-silver ores, in the Tetiuhe valley, are still in the field of possibilities. For many years gold alone was produced, in part from the coastal rivers and in part from a quartz-vein on Askold island near Vladivostok. But the production is diminishing, and prospectors are looking for other rivers in the interior, such as the tributaries of the Ussuri. These rivers are now more accessible than formerly, due to the slow but gradual development of colonization by the Russian peasants. The few natives of the country, called Orodjones, are of the Chinese race. They resemble the North American Indian and are hardy fur-hunters. They have given some attention to placers and have already shown good specimens of gold-dust from the rivers Iman, Bikin, Noto, etc. Coal-mining was begun in the Vladivostok region more than 20 years ago, but in a somewhat irregular way. The industry is not as yet important and the best coal-seams are badly prospected, or are even neglected. Copper, lead, and iron exist in several places. The amounts give some encouragement to the anticipation that the discoveries will give rise to important metallurgical works. I here present a review of the various deposits, based upon such safe information as is in hand, when I have not drawn upon my personal observations. Fig. 1 is a map of Eastern Siberia, showing the mineral deposits.

Jan 1, 1913