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By Edward G. Cunney

Track in underground bituminous coal mines was investigated and technology was taken from other industries in order to obtain information on conditions that impair the safety and efficiency of the track and to develop guidelines and useful information on the construction, inspection and maintenance of mine track. Volume 1 contains information on the investigations, observed track conditions, useful technology from railroads and other industries, derivations of track condition descriptors and limits, conclusions, and recommendations. Volume 2, Guidelines, contains recommended standards and practices for mine track. It includes the relation of track conditions to safe speeds; descriptions and limits for measurable track features, such as gage; descriptions of conditions for track components that are normally not measurable, such as subbase soils; construction requirements and techniques; inspection requirements and methods; and methods for managing and performing track maintenance work. It does not repeat the summary or? derivations. Volume 3, Inspection Handbook, summarizes recommended standards and procedures from Volume II and provides related information for ready reference by inspectors in the mines. As a research product to be used in mines, it does not repeat the summary, derivations or references.

Jan 1, 1977

By A. C. Richardson

[During the past two and a half sears the U. S. Bureau of Mines and the University of Alabama, with the cooperation of the different coal operators, have been making an extensive studs of coal preparation in the State of Alabama. Considerable time has been devoted to the studs of the washing characteristics of the Mars Lee bed and the various methods used In preparing from it a low-ash coal suitable for the manufacture of metallurgical coke. One of the phases of this problem is the utilization of middlings products from the washing plants. This paper gives the results of treating jig middlings on a coal-washing table at the Bureau of Mines laboratory at Tuscaloosa, Ala. The sample used was secured from the Sayreton washery of the Republic Steel Corporation, Sayreton, Ala. WASHERY PRACTICE The Mary Lee bed is very bony, and operators find it difficult to produce from this bed a washed coal much under 10 per cent ash. Experience has shown that in the preparation of a coking coal from the Mary Lee bed it is best to use a process which permits the recovery of a middlings product. Middlings are desirable because separation according to specific gravity is never perfect, and a middlings product makes possible a low ash in the primary warned coal without excessive losses of combustible in the refuse. The general washery practice on the Mary Lee bed is to crush the run-of-mine coal through some maximum screen size and wash it upon some one type of jig without re-treatment of any of the products made. The maximum size treated varies from 3 inch to J inch. The middlings product from multiple-cell jigs is usually termed "boiler fuel" and when possible is utilized as such. At present the production of boiler fuel is often in excess of power requirements, and the surplus, due to its high ash content, becomes waste.]

Jan 1, 1931

By E. M. SEELEY, F. S. LOTT

The total capacity of the natural-gasoline industry to produce light hydrocarbon products increased to 21,322,000 gallons ( 507,670 barrels ) daily on January 1 , 1948 , from 17,928,000 gallons ( 426,860 barrels ) daily on January 1 , 1946. Expansion of the industry in the first two post -war years , 1946 end 1947 , thus averaged 9 percent annually , compared with 6 percent annually in the last two war years , 1944 and 1945 . The number of cycle plants increased only from 37 to 39 in the years 1946 and 1947 , and total capacity of these plants gained 21 percent to 5,857,000 gallons de ily on January 1 , 1948 , represent ing 27.5 percent of the total capacity of the industry , compared with 27.0 percent on January 1 , 1946. All other plants decreased in number in the two-year period from 589 to 510 on January 1 , 1948 , but their total daily capacity increased 18 percent to 15,465,000 gallons . The daily capacity of the average plant in the industry was enlarged from 28,600 gallons on January 1 , 1946 , to 38,800 gallons on January 1 , 1948 , continuing the long -established trend to producing units of greater size and efficiency . The average cycle plant capacity increased from 131,000 gallons daily to 150,200 gallons daily on the same dates as the average capacity of all other natural -gasoline plants increased from 22,200 gallons to 30,300 gallons . Owing to the elimination of small , obsolescent plants in Illinois , Oklahoma , and Pennsylvania , these States experienced the greatest reductions in numbers of plants in 1946 and 1947. In Oklahoma and Texas , several consolidations of two or more plants into a single operating unit were reported . Louisiana and Mississippi were the only States in which the number of plants increased , but daily capacity to produce light products was larger in eleven States on January 1 , 1948, than two years earlier . Added facilities in California and Texas accounted for 41 and 36 percent , respectively, of the national gain in capacity .

Sep 1, 1948

By G. M. Potter

During the investigation of the occurrence of manganese deposits in the western United States, examining engineers of the Bureau of Mines collected samples from four properties in Siskiyou and Mendocino Counties northern California. As the ores were too low-grade to be acceptable to manufacturers of ferromanganese, beneficiation studies were made between 1941 and 1945 to determine the amenability of the ores to concentration. The Johnson and Reynolds properties are near Fort Jones Siskiyou County. The ore occurs in a number of small lenses in that area. Samples were taken for testing for amenability to treatment in a small custom-gravity plant, tentatively planned. by the Waiter Johnson interests of San Francisco. A 2-ton representative sample was obtained from numerous exposed portions of an outcrop on the property of the Mayland Mining Co. The Mayland mine is about 8 miles from Sawyers Bar in Siskiyou County. The ore body consists of stringers and irregular masses of oxide, and. silicate ore scattered through quartz, which these minerals have replaced.

Jan 1, 1952

By B. W. Moore

The U.S. Bureau of Mines investigated the separation of heavy rare-earth elements (REE) in an ion-exchange process. An ion-exchange column consisting of two sections, a loading section and a separation section, provides high levels of REE loading and good REE separation with an expected processing cycle of less than a month, while current ion-exchange technology requires more than 5 months. A different resin is used in each section: sulfonic resin in the loading section and iminodiacetic resin in the separation section. The separation section is further divided into two segments: the first conditioned with NH4 and the second with acid. Erbium is loaded onto both segments of the separation column as a retaining ion. Bands of mixed REB eluting between separated bands of pure REB were recycled directly to the column. Without mixed-band recycle, over 80% of the REE eluted from the column was separated into fractions with 99% purity of each element; with such recycle, the percentage of separated elements can be increased to around 90%.

Jan 1, 2010

By W. W. Staley

This paper discusses the design of small head frames that will fill the needs of prospectors and small operators whose operations are conducted through shafts. The head frames considered were designed to handle relatively small tonnages. It was assumed that the shafts in which buckets are used would not exceed 300 feet in depth and that not over 60 tons of rock would be hoisted, in, 14 hours. In the design of the larger head frames, a hoisting capacity of about 250 tons per 6 hours from a depth of 300 to 500 feet was assumed. Under these conditions, hoisting speed, rate of acceleration, and weight of rope have a negligible effect on the head frame design and, therefore, have been ignored in the following, discussion. Because timber is relatively cheap and easily obtained in most mining areas, the discussion has been confined to timber construction.

Jan 1, 1937

By Charles D. Litton

This U.S. Bureau of Mines report details the results of a series of large-scale experiments where small coal fires were used to ignite the conveyor belt at air velocities ranging from 0.76 to 6.1 m/s. In the tests, electrical strip heaters imbedded within a pile of coal were used to heat the coal to a point of flaming ignition. The flaming coal subsequently ignited the conveyor belt located approximately 5 to 10 cm above the coal pile. During the tests, temperature, CO, and smoke levels were continuously measured in order to determine both alarm time and level as the fire intensity progressed through the stages of smoldering coal, flaming coal, and flaming coal plus flaming belt. Analysis of the data leads to certain conditions of air velocity and sensor alarm levels that are required for early detection of conveyor belt entry fires. Two nomographs are presented, which define sensor alarm levels and sensor spacings as a function of belt entry cross-sectional area and belt entry air velocity.

Jan 1, 2010

The Bureau of Mines conducted a field study of respirable dust concentrations at an underground room-and-pillar oil shale mine and at the aboveground milling facility to determine the dust generation sources, personal respirable exposure, characteristic minerals, and size distribution of the dust. Major dust sources in the mine were the scaling and blasthole drilling operations, and major dust sources in the processing mill were the screening and crushing operations. Principal minerals found in the airborne respirable dust were albite, analcite, calcite, dolomite, quartz, and orthoclase. The average alpha-quartz content of mine and mill respirable dust samples was 4.1 pct and 15.5 pct, respectively. Carbonaceous material such as diesel particulate accounted for approximately 75 pct of the respirable particulate found in the mine. The average coefficient of variance of respirable dust concentrations measured with approved personal dust samplers in the mine and mill was 7.6 pct, the best precision observed to date with the personal dust sampler operated in the field.

Jan 1, 1977

By Richard L. Fischer

Constant-volume charges of precipitated PETN (pentaeythrite tetranitrate) at three specific gravities (0.50, 1.00, and 1.50) were used in laboratory tests to examine the effects of changes in explosive properties on free-surface displacement pulses and on crater dimensions. The tests were performed in large blocks of cement-mortar. The values for the detonation velocity, detonation pressure, specific energy, energy density, and energy release rate were calculated from the explosive loading density. Calculated explosive properties were correlated with free-surface displacement pulse measurements, strain energy, and measured crater dimensions. Increases in explosive properties resulted in increased free-surface displacement pulse parameters and crater dimensions. The loading density, detonation velocity, energy density, detonation pressure, and energy release rate were found to be best indicators of explosive performance. Simple acoustic relationships involving impedance ratios were examined and could not be used to predict peak displacement amplitude or strain energy. Data are presented in the customary English units as well as the International System of Units (SI).

Jan 1, 1970

By R. E. Heithecker

The principle of determining volumes of liquid by alternately drawing in and discharging given quantities of the fluid from a confined space or compartment of known volume and mechanically counting the number of displacements is well established. This is true particularly in water measurement. For several years, oil meters employing the same basic principle have beer used for gaging oil production from individual wells, groups of wells, and in some areas for metering the entire production from a property. Especially in areas where there is town-lot drilling and space for tankage is at a premium, oil meters have been used successfully to gale the oil. This facility has obviated the necessity of installing gage tanks. Oil meters also have been used in pipe-line and refinery operations and in loading tankers. Present knowledge e of the subject shows that positive-displacement oil meters can be used for measuring crude oil in the field and elsewhere, provided the meter-counter mechanism is in proper adjustment and the oil has been studied sufficiently to determine the pro-per factor to be applied to the volume as registered by tae meter, possible the adjustment for the shrinkage of the oil caused by liberation of gas from solution.

Jan 1, 1938

By Alvin Kaufman

Following the gold discoveries of the late 1800's much was written regarding the vast mineral resources of Alaska, and much interest was aroused, and yet over the years little has been done to exploit those resources. Between 1906 and 1935 the Kennecott copper mines of the Copper River region were the keystone of the mineral economy (fig, 1). After the depletion of the Kennecott ore reserves and aided by the statutory rise in the price of gold, the yellow metal became the major mineral commodity. In recent years it has shared the honors with coal and sand and gravel. Although this trend should indicate the development of a stable, diversified mineral industry, yet the trend of production is downward. This report results from a study by the Federal Bureau of Mines to delineate the problems and to forecast the growth of the mineral industries in Alaska. The need for such a blueprint for the future was enhanced by the population explosion in the United States and the consequent eventual need for additional living space, as well as the current interest in new areas, and the necessity to develop reserves of strategic minerals.

Jan 1, 1961

By S. L. May

Investigations by the Federal Bureau of Mines indicate that hafnium and zirconium compounds of acceptable purity can be extracted from Nigerian zircon concentrates. Chlorination and caustic soda fusion techniques were used to extract 85 to 95 percent of the valuable metals from the concentrate. The extracted hafnium and zirconium compounds were purified by recrystallization of the oxychlorides or by formation of complex salts during chlorination. The zirconium-hafnium product of the recrystallization method contained 15 parts per million of uranium, and the product of the salt-complex method contained less than 10 parts per million of uranium. The hafnium was separated from zirconium by solvent extraction methods. A zirconium product containing 0.3 percent hafnium and a hafnium product containing 4 percent zirconium were obtained. At the request of the Atomic Energy Commission (AEC), work was started to develop techniques for processing Nigerian zircon concentrates in commercial installations presently engaged in producing zirconium and hafnium metals from ores. The Nigerian zircon has a high hafnium content, but the presence of uranium and thorium is a problem not normally encountered in processing zircon concentrates.

Jan 1, 1961

By Irving Hartmann

[The explosability of coal dusts has been the subject of many investigations studies have been conducted in laboratories, in galleries and in coal faire; of several countries to obtain information on the causes, development, and prevention of mine explosions. Early laboratory experiments on it American colas dealt with pressures developed in test bomb by explosions of dust clouds and with, the effects of gas in the dust atmosphere.5/ Later, the emphasis shafted to evaluation of the relative fleet flammability and the ignition temperatures of coal dusts.6/ Much worthwhile effort was devoted to the development of Laboratory apparatus and test procedures that gave good correlation with large-scale explosion tests in the Experimental cost mine. In recent years a number of special problems were studied, mostly with bituminous Pittsburgh coal dust]

Jan 1, 1954

By Robert G. Lundquist

This report summarizes all relevant findings and conclusions regarding capabillty of high-energy projectile impact to operate effectively in an open pit mining environment and to successfully handle secondary breakage and bench scaling problems. A silenced, aimable, mobile projectile launcher was designed and fabricated, utilizing a Government-furnished smooth-bore, 90 mm cannon. The silenced launcher was tested at the contractor's test site prior to shipment to ANAMAX Mining Company's Twin Buttes Mine near Tucson, Arizona. Demonstration tests were conducted at an inactive waste dump in the mine on 39 oversize boulders to determine the relationship between boulder size and projectile energy required for secondary breakage. The high energy projectile impact method (known by the acronym REAM -Rapid Excavation and Mining) was tested on an additional 23 boulders in the working mine and on 31 areas of potentially loose rock high on the pit walls. Most of the secondary breakage tests were successful and acceptable for open-pit mining purposes without producing large amounts of fly rock. Five of the 31 scaling tests were successful with one shot, but most of the remainder required two or more shots, and a few could not be dislodged because they were not as loose as they appeared to be, based on visual examination from a distance. Cost comparisons between the REAM method and conventional methods of secondary breakage and bench scaling are discussed. A film documentary, REAM--Mining Applications of High Energy Projectile Impact, has been produced by the contractor depicting the applications of the silenced cannon.

Jan 1, 1976

By L. H. McGuire, L. B. Berger

"During the period October 31 to November 4, 1944, tests were conducted by the Bureau of Mines in the Cascade Tunnel of the Great Northern Railway Cc. to determine the effects upon the tunnel atmosphere of the use of a Diesel freight locomotive through the tunnel. These tests were conducted at the request of the company to ascertain whether undesirable conditions might be caused by the discharge of Diesel engine exhaust gas in the tunnel, which was constructed for an electric haulage system and is not provided with equipment for mechanical ventilation. The use of Diesel locomotives on the division that includes the Cascade Tunnel was under consideration as a means of augmenting haulage facilities for the abnormal freight tonnage that must be handled during wartime.As the Bureau of Mines has received requests for information on the extent of contamination of the air of railroad tunnels by Diesel locomotives, this report was prepared to make available for general information the data obtained during the tests in the Cascade Tunnel. As the test locomotive is of a type used on other railroads, and as the bore and grade of the tunnel and the tonnages moved are comparable to such factors on other roads, the data should be sufficiently representative to be of general interest. The exceptional length of the Cascade Tunnel made it an excellent location for obtaining information on the composition of the tunnel air and on the movement of air induced in the tunnel by the passage of trains.The writers are indebted to C. O. Jenks, vice president of the Great Northern Railway Co., who arranged for the tests, and to the following personnel of the railroad who cooperated in the conduct of the tests: I. E. Clary, superintendent, Spokane Division, J. L. Robson, superintendent of motive power, oil and gas equipment, J. F. N. Gaynor, superintendent of electric operations, William Lowney, master mechanic, Spokane Division, and D. F. Marston and Verne Nelson, assistant superintendents of electric operations.The Cascade Tunnel is on the Spokane Division of the Great Northern Railway and pierces the Cascade Mountains some 49 miles west of Wenatchee, Wash. The west end of this division is electrified from Appleyard Station, 2 miles east of Wenatchee, to Skykomish, Wash., a distance of 73 miles. Until the described tests, only electric haulage had been employed through the tunnel since it was first opened to traffic in January 1929.The Cascade is the longest railroad tunnel in the United States - 7.79 miles. The tunnel is single-track, perfectly straight, concrete-lined, and is on an essentially uniform grade of 1.56 percent, ascending from west to east. The cross-sectional area of the tunnel is 314 square feet, the dimensions being shown in figure 1. Elevation of the east portal is 2,880 feet and of the west portal, 2,240 feet."

Jun 1, 1946

By J. J. Shields

The Bureau of Mines observed two different types of longwall mining; the advancing longwall method and the retreating longwall method at seven bituminous coal mines located in five of the coal producing states. In two mines using the advancing face method, the coal faces were abandoned because of roof failures and poor production. In the other five mines using the retreating method, roof control was good as was production. The success of longwall mining depends on good roof control and good production. The use of self-advancing hydraulic roof supports, such as Westfalia, Dowty, and Wanheim props along with Westfalia coal planers and the Anderton and Eickhoff shearer-loaders have been a factor in recent successes.

Jan 1, 1967

By John H. Soule

The Royal John mine was examined in November 1942 by a mining engineer of the Bureau of Mines, who proposed development of the Royal John and other properties in the area. Geologists of the U. S. Geological Survey studied the area in 1943 and 1944 and made definite recommendations. Also, in 1943 the Peru Miring Co. mapped the Royal John and did considerable diamond drilling. The Bureau of Mines started the Royal John portion of a project pertaining to the general district in April 1944. This project was completed in Juno 1945. The work, consisting of diamond drilling, was supervised by Robert O. Hill, mining engineer, and the results were published in Report of investigations 3904, Exploration of Grey Eagle, Grandview and Royal John Claims, Grant County, N. WIC. In 1947 and 1948 the Royal John was re-examined by a Bureau engineer, and additional development to increase the reserves of low-grade lead-zinc ore was proposed. This project was started in August 1948 and completed in Juno 1949.

Jan 1, 1950

By A. E. Isaacson

The U.S. Bureau of Mines determined the effect of common sulfide minerals on the corrosion rates of various types of ferrous alloy grinding media. Data obtained from this study will aid in determining the contribution of any electrochemical reactions between sulfide minerals and grinding media to the total grinding media consumption. Common sulfide minerals used in this study were chalcopyrite, galena, and sphalerite. In the presence of oxygen, chalcopyrite was found to increase the corrosion rate, galena was found to decrease the corrosion rate, and the effect of sphalerite was dependent upon the type of grinding media. Possible electrochemical reactions of these minerals in the presence of grinding media are suggested.

Jan 1, 1989

By Heine Kenworthy

In 1930 the Shenandoah-Dives Mining Co. near Silverton, Colo., put into operation a newly erected, 300-ton selective flotation plant to mill complex ores from its nearby mine. The operation was a steady producer and was enlarged to treat 600 to 800 tons a day. In 1942 the company opened and started milling an area in the mine containing semioxidized ore. The valuable mineral. Content of this ore was considerably higher than in the straight sulfide ore previously handled alone. The mixture of clean sulfide and semi-oxidized ore was difficult to treat; consequently tailing losses, especially with respect to lead, were high. A. few years later, in order to study the possibilities, of obtaining higher recoveries by a modification of the mill flow sheet, a 1,200-pound sample of mill feed, taken over a period of several days by the company, was submitted to the Mississippi Valley Experiment Station for testing. Although this sample proved to contain more than twice as much lead as the average yearly mill feed, the same problem of recovering the oxidized values were present.

Jan 1, 1948

By John Durkin

A computer model has been generated to evaluate speech intelligibility of individuals wearing conventional and electronic hearing protectors. For speakers talking at normal levels in noise levels of 65 db(Lp) or less, it was found that conventional hearing protectors significantly reduced speech intelligibility. Under the same conditions, electronic protectors provided scores equal to those for the unprotected individuals while providing protection from high noise levels. Therefore, electronic hearing protection is valuable in areas where high noise level is intermittent.

Jan 1, 1979