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By H. J. Ward

RUM Jungle uranium field lies in the subtropical portion of the Northern Territory on the Finniss River, East Branch. It takes its name from a railway siding about 2 ½ miles to the southwest and 52 miles from Darwin. The field can be reached from Darwin by a bituminized road. Monsoonal rains of the wet season, October to April, provide an annual rainfall of about 60 in. Vegetation is of the open forest type with denser tree growth along the watercourses and scattered throughout the area are isolated dense patches of jungle growth which are always found on ironstone cappings overlying limestones. The name, Rum Jungle, is thought to have been derived from this unusual occurrence of jungle growth. The wet season prevents the movement of motor vehicles and personnel. It is not until March, when the grass which ranges up to 15 ft in height is burned and the alluvial flats dry out, that field work can be undertaken.

Jan 12, 1954

By F. R. Hensel

The present study was made to determine the laws governing the formation of the primary? crystal structure during solidification. Most of the experiments were carried out on chill castings, but from the resiilts it will be possible to draw certain conclusions as far as sand castings are concerned. It is necessary to discuss first a number of theories, which are generally adopted for explaining the structure of an ingot. Usually, the structure of an ingot consists of the following three zones (Fig. 1): (1) a chill layer of small at-random oriented crystals; (2) a layer of columnar crystals; (3) a zone of equiaxed crystals. The tensile properties of the chill layer and the equiaxed range are usually much better than in the columnar range, particularly the planes that are formed by the columnar crystals growing from two sides at right angles have low tensile properties. This is one of the reasons why columnar crystals in ingot structures are undesirable.

Jan 1, 1937

By AIME AIME

H OWEVER extensively water-lines may be laid in the mine for fire fighting purposes, there are still, usually, points being worked temporarily, development, stoping or other work of a temporary or incidental nature where it is considered that the expense of laying fire-lines is not warranted. While the laying of water-lines in some sections of the mine may not be warranted, in most metal mines it is necessary to lay an air-line to all working places. In the mine of the United Verde Extension Mining Co., at Jerome, Ariz., advantage has been taken of this fact by providing a means of by-passing the water at the end of the water-line into the air-line in case an emergency arises. By this means the 2-in. air-line can be quickly converted into a water-line for fighting fire which might otherwise be beyond the reach of the water-lines.

Jan 1, 1930

By A. H. Roberson, L. H. Banning

DURING the past few years, a considerable tonnage of ilmenite has been produced as a byproduct of a monazite dredging operation and stockpiled near Boise, Idaho. This ilmenite has not been marketed because of the long distance from ilmenite-consuming areas and its comparatively low TiO2 content. Production of monazite from the alluvial sand deposits of Idaho is a mar- ginal venture when it is the only marketable product, and it will be necessary to establish a byproduct market before the operation becomes economically stable. Early in 1954, the Bureau of Mines Northwest Electrodevelopment Laboratory at Albany, Ore., conducted a series of tests which demonstrated that arc furnace smelting could be utilized to produce commercial quality pig iron and a high titanium content slag from these ilmenites. Additional studies showed that the slag chlorinated readily to produce a satisfactory yield of TiCl4. The investigation was carried out by two research teams. The Ferrous Metals Branch, with adequate

Jan 1, 1956

By Saburo Shigeno, Kunzo Amano

As shafts and tunnels move deeper levels in underground mining, development planning becomes more complex. The most serious problem is the aggravation of environmental conditions due to the imposition of higher-than-natural temperatures upon exposed strata. Since such a problem is a potential hazard to health, safety, and production, the authors have developed a system of computer-derived ambient-air temperature data for every major point of an underground mine under a given set of conditions. This system is comprised of two subsystems: 1) Ventilation network analysis, 2) Estimation of air - current temperature. The former is based on the Hiramatsu-Oka method, an improvement of the Scott-Hinsley method. The Hiramatsu-Oka method allows fast convergence and consideration of various fan characteristics. The latter subsystem considers heat radiation from strata, and the humidity. In several tests conducted at Besshi and Sazare Mines of Japan, the computer-derived data correlated with actual conditions.

Jan 1, 1969

By Patrick M. Hurley

The relationships between mineral deposits and various plate margin mechanisms are examined under the constraints of radiogenic isotopes and other geochemical indicators. It seems like1 y that: (1) deposits of the spreading ridge association are fairly ubiquitious through most of geologic history and can be recognized by the lithologic assemblage and primitive lead isotope ratios; (2) most metals in the island arc association are not derived entirely from a subducting oceanic plate, and have a partly continental affinity; (3) subduction beneath a continental plate generates ores which are derived either from the downgoing plate or from the lower crust; (4) the heating of a continental plate by thickening or by mantle plumes may develop a metallogenic province involving extraction of metals from the curst; (5) rifts and grabens developing thick sections of marine sediments with evaporites may be the locus of base metal mineralization by movement of reducing brine solutions resulting from diagenesis and bacterial reduction of sulfates

Jan 1, 1978

By E. P. Peleider

DIAMOND drill research work was initiated at the School of Mines, University of Minnesota, in late 1949. The Drilling Symposium held in Duluth that spring highlighted the problem of high cost and core recovery and the need for controlled testing. An advisory committee made up of informed representatives of both mining companies and drilling companies was formed to suggest and advise on a program of drill research. A Hy-Mac hydraulic drill unit, see Fig. 1, especially designed for experimental testing, was obtained for this work by the School of Mines through the courtesy of the Carboloy Co. It is an extremely flexible unit, capable of exerting a forward thrust of about 1750 lb and turning at speeds from 650 to 2200 rpm. The feed arrangement is so designed that the advance can be set either at a constant rate or permitted to vary at a fixed Pressure, see Fig. 2. The

Jan 1, 1953

By E. P. Peleider

DIAMOND drill research work was initiated at the School of Mines, University of Minnesota, in late 1949. The Drilling Symposium held in Duluth that spring highlighted the problem of high cost and core recovery and the need for controlled testing. An advisory committee made up of informed representatives of both mining companies and drilling companies was formed to suggest and advise on a program of drill research. A Hy-Mac hydraulic drill unit, see Fig. 1, especially designed for experimental testing, was obtained for this work by the School of Mines through the courtesy of the Carboloy Co. It is an extremely flexible unit, capable of exerting a forward thrust of about 1750 lb and turning at speeds from 650 to 2200 rpm. The feed arrangement is so designed that the advance can be set either at a constant rate or permitted to vary at a fixed Pressure, see Fig. 2. The

Jan 1, 1953

By J. C. Konopka, S. A. G. Poppen, E. K. Roesner

Many shafts have experienced stability problems during shaft sinking because the designer failed to fully appreciate the conditions he would encounter. Some shafts have failed during construction because the ground supports provided to compensate for the expected conditions were inadequate despite the most careful investigations and analyses. To design a ground support which is ultimately safe to achieve stability during shaft sinking would be too costly and impractical and, therefore, many shafts would simply not be constructed. The design of a ground support for shaft sinking based on an intimate understanding of the expected ground behaviour and stress development during excavation combines the art of mining with the science of geotechnical engineering. Where no historical design data is available, the designer of the ground support must: 1. classify the rocks and soils and assess their behavioural characteristics; 2. calculate the primary and secondary stresses; 3. design and/or select a ground support system which will ensure stability of the excavation during shaft sinking.

Jan 1, 1983

By David Burgess, Hershiel H. Hayden

Experiments at the Somerset mine, Colo., under an agreement between US. Steel Corp. and the US. Bureau of Mines are described. A test was made of the tube bundle method of mine air sampling which was developed for European longwall mines; some 300,000 running feet of tubing provided continuous monitoring at 38 locations. Carbon monoxide concentrations were obtained with standard deviations of less than 1 ppm and oxygen concentrations with standard deviations of less than 0.2%. A base level of CO index (ppm CO evolved per percent 0, removed) was determined to be zero to 20 through most of the passageways of the mine. However, in one working section where the coal was initially hot (about 180°F within a pillar) the CO index was demonstrably higher, 120 trending upward to about 60 when smoke appeared and the section was sealed. The data are discussed in terms of laboratory experiments on CO evolution from coals.

Jan 1, 1977

By N. E. Rogen, N. J. Grant

AGE-hardening in nickel-chromium-titanium-aluminum alloys in the composition range characterized by the Nimonic alloys, is dependent upon the precipitation of the Ni3(AI,Ti) (y') phase.1 This phase is found to precipitate at about 700°C.1 Ni,Al is a face-centered-cubic ordered structure with a lattice parameter of 3.560 A. The atomic configuration is such that the aluminum atoms occupy the cube corners and nickel occupies the cube faces with titanium substituting for the aluminum preferentially. A maximum of three out of every five aluminum atoms can be replaced by titanium atoms in the -y 'phase.' When the solubility of the y'-phase is exceeded for titanium the T(Ni,Ti) phase is formed. The T-phase is an ordered close-packed hexagonal intermetallic structure which shows little solubility for the other elements in these alloys. The lattice parameter for T-phase is a - 2.5454 kr and c = 8.2900 kx units."

Jan 1, 1959

The economic recovery of metals from dilute solutions has been the dream of mining engineers for many years. This subject is now receiving greater attention, particularly for copper, in view of the heightened demand for the metal and the tightening supply situation. A Copper Precipitation session, sponsored jointly by EMD Hydrometallurgy Committee and MBD, which took place during the Annual Meeting in March, heard papers on recent research and plant practice. Although the bulk of research in hydrometallurgy has been carried out in countries other than the United States1, producers in this country are making important contributions to the heap or dump leaching system. They realize that the processes are essentially simple to install and give high recovery rates at reasonable cost. Jacobi estimated in 1963 2 that the copper mining industry obtained a gross return from scavenging operations -on a worldwide basis-on the order of $20 million annually, subject to the usual deductions for refining and realization charges, overheads, taxes, etc.

Jan 6, 1966

By Bunting S. Crocker

In the summer of 1961, the Anaconda Research staff and Kilborn Engineering Ltd. began a study to investigate the possibilities of using some form of autogenous grinding in the new concentrator which Anaconda was planning to erect at Butte, adjacent to their Berkeley pit. The following criteria applied to the project: 1) The Butte mill was to be able to handle 36,000 to 42,000 tpd of copper ore, taken from the Berkeley pit and adjacent underground mines. 2) The plant was to be built in six units. 3) It would be started up two units at a time. 4) Equipment from the Anaconda mill was available for use in the new location. 5) Tonnage would be maintained at Butte and Anaconda, with equipment being moved down as required. 6) The ore from the Berkeley pit was known to vary widely from place to place in the pit and to be generally soft and friable.

Jan 5, 1964

By S. F. Reiter, R. W. Guard, J. H. Keeler

DURING the last several years the authors have been conducting tests on a tensile machine that autographically records load-elongation data. In certain tests at elevated temperatures on face-centered cubic, hexagonal close-packed, and body-centered cubic materials (binary alloys of nickel, zirconium, and iron), the load-elongation curve as shown in Fig. 1 reaches a maximum load (Pmax,) at relatively small amounts of strain and a large amount of elongation occurs subsequently with a continuously decreasing load, until finally localized necking and fracture take place. This early maximum load behavior has been found without the accompanying evidence of localized necking as has been assumed by some, or of evidence of cracking as observed by others.' This behavior has also been observed by Nadai and Manjoinez whose results are in good agreement with ours. The prior strain, strain rate, test temperature, and crystal structure affect the observations. The influence of prior strain was observed in tests on unalloyed zirconium at 300°C in which specimens containing large amounts of prior strain (cold work) exhibited the type of curve shown in Fig. 1. No localized necking was observed after strain as much as that of point B. Annealed and recrystallized specimens of the same material showed a load-elongation curve with maximum load occurring after considerable strain hardening and at the beginning of localized necking. Interrupted tests (Fig. 2) show no loss in strength because of recovery or recrys-tallization during an interval at temperature without load. Recovery under stress such as found by Wood and Suiter3 in aluminum is now being investigated as one possible explanation. The strain rate is a contributing variable as shown in Fig. 3, a test on high purity nickel. Here the strain rate was decreased by a factor of ten during a test in which the maximum load was reached at a small strain. The slope of the true stress-true strain curve was positive with the more rapid strain rate and negative with the slower strain rate. In many binary ferrites an added effect of temperature has been observed. Fig. 4 shows the load-elongation plots for a binary ferritic alloy containing 2 pct Mo. The slope of the small portion of the stress-strain curve obtained at a strain rate of 0.01 mhr1 changes sign from negative to positive on going

Jan 1, 1955

By John Henry Harden

THIS shaft, located in the northern anthracite coal-field about 2300 feet southwest from the court-house at Wilkes-Barre, in the County of Luzerne, Pa., is the property of the Lehigh & Wilkes¬Barre Coal Company. The sinking and cribbing to the solid rock (see isometrical view on Plate IX) was conducted by Mr. W. W. Kenrick. Dimensions of the earthwork to the foundation of the cribbing, 51' 1/2" long, 17' 4" wide, 31' deep. Total amount of excavation in cubic yards, 998.5. Dimensions within the permanent cribbing, 45' 4" long, 11' 16" wide, 31' deep, divided into six parts by buttons 8" x 12", each division, 7' x 11’ 16". Permanent cribbing 12" x 12"; temporary cribbing 8" x 10"; backing, 3" thick ; clay puddle to ex¬clude surface water, 12" thick; conductors, 8" x 5"; lining, 1" thick from top to bottom of the shaft. In the latter part of the year 1871, Mr. H. Murray & Son contracted with the company for the continuation of the work at the rate of four hundred dollars per yard in depth, to a point 100 feet below the Hillman seam of coal ; for the succeeding 100 feet the price to be increased twenty-five dollars per yard, and so on until the bottom rock of the Baltimore seam of coal was found. The size of the shaft within the cribbing timbers is 45 feet 4 inches by 11 feet 6 inches, having six divisions of equal dimensions, 7 feet by 11 feet 6 inches, giving room for what is known as the" standard diamond" car, whose capacity when level full is 100 cubic feet, but when loaded by the miner 4 inches above the top contains 112 cubic feet.* Two divisions of this shaft are intended for hoisting coal from the Hillman seam, two from the Baltimore seam, one for ventilation, and one for pumps. The works were planned for two pairs of direct-acting, high-pres¬sure engines, twenty-four boilers, and for an estimated output of 2500 tons of coal per day from the two seams. * Size of the "standard diamond" car, 8' 10” x 4' 3" x 2’ 8” = 100.1.4; loaded 4 inches above the top, 8' 10” x 4’ 3” x 3’ “0"= 112.7.6.

Jan 1, 1877

By L. F. Stutzman, George Thodos

The friction factor plot presented by Cornell and Katz4 and developed for the flow of fluids through consolidated formations has been directly adapted for handling fluid flow problems involvitrg both linear and radial flow. In this adaptation the friction factor plot is used directly for the solution of problems and thereby eliminates the use of conventional equations which are specific to laminar (Darcy) or turbutent flow. This upproach overcomes the disadvantages inherent in the use of these conventional equations. It eliminates the necessity of checking the type of flow occurring in order to identify the specific equation which must be used. In radial flow problems, because of the increasing mass velocity of the fluids as they approach the wellbore. the type of flow may no longer remain laminar. Consequently, it is necessary to use more than one equation in a problem and to identify the range over which each equation should be applied. Finally, in practice it has been found that much of the flow of gases through consolidated media occurs in a range that is neither laminar or turbulent. For this transitional region, no convenient equations are available. The method and presented friction factor plot are appficahle to both liquids and gases. INTRODUCTION The flow of fluids through unconsolidated media in packed beds has been treated extensively by a number of investigatorsl,2,3,5,7,8 Most of these studies present friction factors as a function of modified Reynolds number similar to those developed for conventional fluid flow through pipes. These friction factor plots are presented for linear flow; however, Elenbaas and Katz have extended these concepts to apply to radial flow. All of these studies on unconsolidated materials require a knowledge of packing properties such as sphericity. porosity, and particle diameter. Sphericity and particle diameter cannot be defined at the present time for consolidated formations such as those commonly found in gas or oil reservoirs. As a result many investigators have not utilized friction factors and Reynolds number in the study of fluid flow through consolidated media. However, Cornell and Katz4 present a plot (Fig. 1) for the flow of fluids through consolidated porous media, in which the friction factor defined as: The turbulence coefficient, P, is related to the formation permeability, K, as presented in Fig. 2. Three different types of flow may exist in the flow ot

Jan 1, 1957

By Michael E. Zellars

The environment for deposition of marine phosphorite is controlled by the relationship of prevailing climatic, oceanographic, structural, and sedimentary conditions. The set, or sets, of conditions that has evoked the accumulation of economic concentrations of phosphorite has been the subject of a number of previous works. Phosphorite presently considered ore is generally in excess of 10% P205 with an extractable phosphate product in excess of 30% P2O5. The concentration of the product in the ore, its amenability to state-of-the-art extraction, and thickness of the overburden are major controlling factors in determining its mineability. A recent survey of phosphorite deposits in the south-eastern United States included a review of the depositional and structural setting for the major areas of occurrence. The application of previous work regarding phosphorogenesis has led to the establishment of a general depositional model for most mid-Miocene primary phosphorites, and, is also possibly applicable to the Bone Valley (Pliocene-Miocene) district of central Florida.

Jan 12, 1978

By S. F. Willey

Difficulties encountered in justifying replacements for overage mobile mine equipment at the Gay mine are common to most mining operations. More critical management reviews, resulting from ever rising capital expenses, increased such difficulties. These increased difficulties are especially apparent to those who are primarily operators and are not statisticians, mathematicians or computer men. The Gay mine is located 17 mi east of the town of Fort Hall in southern Idaho. This open pit operation annually supplies the J. R. Simplot Co. and the FMC Corp. with 1.5-2.0 million tons of phosphate ore. Stripping ratios average approximately three bank cubic yards of waste per ton of ore mined. The mobile mine equipment fleet consists of ten 24-cu yd scrapers; twenty-one 30-50-ton end-dump trucks; four 3%-4%- cu yd shovels; fifteen dozers in the D-8 and D-9 classes; and three road patrols. Equipment replacement is based on the results of evaluations made on individual units.

Jan 9, 1972

By Franz Wever

The importance of the Widmanstätten structure to structure theory in metallography has been recognized by many writers.l It is a structure produced by the precipitation of a, new phase from a solid solution upon cooling as a result of changing solid solubility, and displays a characteristic appearance indicating a crystallographic relationship between the new phase and the original solid solution (Fig. 1). First discovered in 1808 by Alois de Widmanstätten2, the structure has been traced by analogy through many alloy systems. Particularly is this true of the steels. Sorby's classic work3 on the microstructure of iron and steel was in essence an attempt to explain the origin of this characteristic structure in meteoric iron. He observed in a Ressemer steel and in a cast-steel ingot structures which we now recognize as typical Widmanstatten figures.4 Osmond Observed structures in a steel ingot analog-ous to those found in meteorites. Arnold and Mc William6 obtained (and recognized) a

Jan 1, 1931

By H. N. Mills

The glass industry is a major user of many industrial minerals in the manufacture of its product. It is the intent of this chapter to: (1) acquaint the reader with the glass industry by including a few production statistics, and then (2) cover the various aspects of the major raw materials used to make glass. Some of the items covered are: type of materials, their function in glass, their composition, cost, and the relative quantity used in glass vs. totals produced. In addition, a discussion of glass raw material specifications, some byproduct materials used in glassmaking, and comments on future prospects related to the environment, technology, and growth are included. The matter of glass compositions, properties, and batches is considered beyond the scope of this chapter which deals only with raw materials. For more details on the particular minerals and rocks, the reader is referred to the commodity chapters in this book.

Jan 1, 1975