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By Wenxue Chen

This paper presents a new type of bolt with full thread and uniform strength, and fabricated with a Glass Fiber Reinforced Polymer (GFRP) bolt-making machine designed by the authors. The mechanical performance of the new bolt is assessed with strength tests conducted with the bolt in acid, alkaline and saline water conditions, with increasing concentration. The purpose is to test the new GFRP bolt?s mechanical performance in harsh conditions, especially metal mines with acid or alkaline environments. Comparison of the color, weight, size and antistatic ability of the GFRP bolt before and after it is immersion in solution is presented. Changes in tensile and shear strength, torsion, and anchoring force were evaluated in the laboratory. The results show that the mechanical properties of the GFRP bolt are more sensitive in alkaline than in acid and saline water. However, the loss ratio of mechanical properties of the GFRP bolt is very small according to the results of tensile and shear strength, torsion and anchoring force. The new bolt can be useful for applications in acid or other harsh mines.

Aug 1, 2013

By J. D. Brown

The electron optics, vacuum system, and sample stage assembly for the Bureau of Mines? electron probe X-ray spectrograph were purchased. Four scanning curved-crystal spectrometers, two reflection- and two transmission-type, were designed and constructed by the authors. The reflection spectrometers are placed in a vacuum chamber for measurement of long-wave-length X-radiation. Detection, pulse-amplitude discrimination, and recording circuits are provided for the simultaneous measurement of four X-ray spectral lines. Minimum spot size is approximately 2 microns in diameter at 30 kilovolts and a sample-to-ground current of 5 x 10-8 ampere. At this voltage and current the limit of detection with reflection spectrometers is less than 0.05 weight-percent for most elements. The limit of detection for elements determined by transmission-type spectrometers, evaluated at 35 kilovolts and 5 x 10-8 ampere, is approximately 0.1 weight--percent for all elements having excitation voltages below 20 kilovolts. In general, reflection spectrometers exhibited satisfactory but poorer resolution than the transmission type, resolution of the spectrometers being limited primarily by crystal imperfections, with greater mosaic structure being introduced by the grinding process for the reflection crystals. Several applications of the electron probe X-ray spectrograph are described. Analysis of a uranium-steel is discussed in detail to illustrate calculation of composition from measured X-ray intensities.

Jan 1, 1962

By A. D. Hunt

THIS PAPER will review Canada's fossil fuel situation as we understand it today and indicate some of the options available to meet our energy requirements during the next 15 years. It would therefore be helpful to examine Canada's total energy requirements and discuss the un certainties of the data base on which we must base future energy investment decisions. On the world scene, Canada is at the top of the energy-consuming nations, using about 49 bbls of oil equivalent per caput/ year. This appears to be slightly ahead of the U.S. and of course much higher than that of many countries. It is generally accepted that there is a more or less direct relationship between energy consumption and material standard of living. However , as we know, Canada, when compared with other industrialized countries on a GNP, an individual-income or some other standard basis, is lower in the list. This situation may be explained by our more severe climate and a relatively small population distributed over a land mass second only to that of the Soviet Union.

Jan 1, 1977

By Alla D. Mah

The energies of combustion of two carbides of tungsten and two carbides of molybdenum were measured , and the corresponding standard heats of combustion were derived . The results are as follows : WC : AH298.15 ( combustion ) = -285,940 ± 250 cal /mole , W₂ C: AH298.15 (combustion ) = -490,660 ± 400 cal /mole , Mo₂ C : AH298.15 ( combustion) = -439,350 ± 600 cal /mole , MoC : AH298.15 ( combustion ) = -269,800 ± 1,000 cal /mole . The combustion heats were combined with the heats of formation of the corresponding metal trioxides and carbon dioxide to obtain the following heats of formation : WC : AH298.15 ( formation ) = -9.6 ± 0.4 kcal /mole , WC: AH298.15 ( formation ) = -6.3 ± 0.6 kcal /mole , Mo₂ C : AH298.15 (formation) = -11.0 ± 0.7 kcal / mole , MoC : AH298.15 (formation ) = -2.4 ± 1.0 kcal /mole . The heats of combustion and formation of MoC are tentative .

Jan 1, 1963

By C. Golumbic

Most early research on solvent extraction of coal has been concerned with the molecular structure of coal. Although rush work is continuing, practical aspects of the subject also are being emphasized. For example, development of the Pott-Broche extraction process resulted from the discovery of very efficient solvents for the pressure-extraction of coal. Recently, Orchin and Storch reported the use of even more efficient solvents under similar conditions. In addition to the discovery of more effective solvents, the possibility of efficient extraction at atmospheric pressure is obviously of practical interest. H. J. Rose observed that phenanthrene at its atmospheric boiling point readily dispersed 80 percent or more of Pittsburgh-bed bituminous coal. This fact served as the starting point of the present investigation, ill which determination of the chemical specificity of this solvent and the chemical nature of the resulting extracts was undertaken. This paper represents a progress report of the results obtained to date.

Jan 1, 1950

By W. L. Dare

This information circular is one of a series the Bureau of Mines plans to publish describing the methods and costs of mining uranium on the Colorado Plateau. The Temple Mountain mining district is unique among the uranium-producing areas on the plateau. This relatively isolated mining district is in Emery County, Utah, on the eastern flank of the San Rafael Swell, about 35 miles southwest of the town of Green River. The district lies just within the eastern escarpment of the San Rafel Reef - a rampart of rugged and tilted sandstone cliffs that encircles the highly eroded core known as the Sinbad Country. The presence of petroleum matter found associated with the ore deposits, the occurrence of uranium in various formations, and the structural deformation caused by collapsed features have aroused a great deal of geologic interest. Mine development on Calyx Flat is distinctive, in that the ore deposits are worked through 36-inch calyx-drill holes.

Jan 1, 1957

By Philippe Caudal

This paper presents a case study in which a slope failure was observed on the west wall of the LAB Chrysotile mine in the vicinity of the main ramp in January 2010. Airborne LiDAR results were used to evaluate slope geometry before and after the failure occurred. Back analysis of the failure was performed to assess rock mass properties at the slope scale using various numerical techniques: limit equilibrium, finite elements and fracture networks. The various approaches correlated well with field observations.

Aug 1, 2013

By Robert R. Perron

The U. S. Bureau of Mines is engaged in many diverse programs for improving mine safety. Of particular interest to the Bureau are new and improved means for minimizing the hazard of fire which can be initiated by prolonged low energy electrical faults on trolley line systems. When a high energy fault occurs on a trolley line, wherein the current exceeds the magnitude normally drawn by legitimate loads, such as locomotives, then the circuit breakers at close-by power rectifier sets trip. Tripping of the breakers not only protects the equipment at the rectifier sets, but also disconnects the energy source from the fault and thereby minimizes the fire risk. However, the fault current is frequently of a level substantially below that required to trip the overload breakers. When the fault is a substantial percentage of the set level of the breakers, the energy dissipated by the fault is frequently sufficient to clear the system by rapidly burning itself clear. Such a fault is often short-lived and does not present as serious a fire risk hazard as a prolonged, much lower energy fault, wherein the energy level is too low to clear the system. The breakdown of a trolley line insulator, in which there was a 15 to 30 ampere fault to ground, would represent such a fault or illegitimate load and a substantial fire risk.

Jan 1, 1975

By W. V. Vietti, E. P. Hayes

OpeRations on the Texas Gulf Coast during 1936 increased materially over 1935. A number of new fields were discovered and a few of the older fields were extended, both by the discovery of deeper pay sands and by lateral expansion of the known producing horizons. Twenty-seven new fields have been discovered, of which 25 are oil fields and the others are gas fields that have every indication of becoming oil-producing areas. Amelia, Anahuac, Bay City, North Pettus, Placedo, Pickett Ridge and Tomoconnor have had major extensions. Production for 1936 amounted to 91,224,844 bbl., an increase of 21,627,033 bbl., or 31 per cent, over the 1935 production of 69,597,811 bbl. The number of producing wells at the end of 1936 was 6727, as compared with 4851 at the end of 1935. Proration has continued in force, thus decreasing the rate of depletion and the number of abandonments normally expected. New Fields A brief discussion of the new fields follows, in addition to Tables 1 and 2, which contain the general data on these fields. Aransas (McCampbell).-Buckingham and McCampbell No. 1 McCampbell was drilled to 7501 ft., then plugged back to 6560 ft. and completed in the Marginulina for a 100-bbl. flowing well on July 18. Bee County.—The Voss field, discovered by Swiger and Devonian's No. 1 Voss, and the Holzmark field, discovered by Miller and Donzis on the Holzmark farm, are both of the same type structurally and are caused by folding against a fault, one field being on one side of a fault and the other on the opposite side of the same fault. Brooks County.—-Standard Oil Company of Texas Garcia No. 1, the discovery well in the Alta Mew field, and Dick Young's Singer No. 1, the discovery well of Alta Verde, appear to indicate small fields. Garcia No. 1 was drilled to 8022 ft. and plugged back to 2485 ft., at which depth the well made 189 barrels. Lockridge.—This gas field was discovered by Gulf Production Company's Fairfield No. 1, in Brazoria County. It was originally drilled to

Jan 1, 1937

By V. E. Edlund

As part of its efforts to devise new and improved methods for recovering lithium from unconventional resources , the Bureau of Mines investigated a lime -gypsum- roast , water- leach technique for processing lithiumenriched ( 0.01-0.68 pct Li ) clays . This report presents the results of a study of the technical feasibility of extracting lithium from raw material representative of clay beds associated with the McDermitt Caldera complex in Nevada and Oregon . prepared from water used Pellets suitable for bench-scale roasting studies were mixtures of minus 200 -mesh clay , limestone , and gypsum , with as the pelletizing agent . Roasting pelletized charges at 900 ° to 1,000° C temperatures for 1- to 4-h periods produced calcines that leached readily , yielding water - soluble lithium sulfate ( Li₂SO4 ) . A 5-3-3 ( weight ratio ) mix of clay , limestone , and gypsum produced calcines with the best leaching characteristics . More than 91 pct of the contained lithium was extracted from pelletized mix batches roasted in covered refractory boats . Lithium recovery decreased to about 87 pct when the mix was roasted under dynamic conditions in a gas - fired rotary furnace . A reaction mechanism was postulated which indicated that dilution and loss of SO2 and oxygen in the combustion exhaust adversely affected the leachability of the dynamically roasted calcine .

Jan 1, 1983

[Secretary's Note.—The following official tables, prepared by the government of the State of Nuevo Leon, and presented to the Institute at the fifth seseion of its Mexican meeting, held at Monterrey, November 26, 1901, present in compact form a general summary of the mineral and metallurgical industry of the State for the preceding calendar year, together with a statement of the railway-shipments of ores from January 1 to October 31, 1901, which, in the absence of direct official mining and metallurgical statistics (not yet available for that year), clearly indicates an increased activity and productiveness of these industries. In other words, the mines are reported to have yielded in 1900 a total product of 83,960,169 kilos of ore; whereas, the railway is reported to have carried, in 10 months of 1901, a total of 108,318,647 kilos of ore. At this rate, the railway-shipments for 1901 mould amount to nearly 130,000,000 kilos. It is, of course, possible that the railwaystatistics include other freight than ores, or that they include duplications, such as would be involved in the record, first of certain ores transported, and afterwards of the " base bullion " produced therefrom. An accurate comparison is therefore impossible ; yet, after making all reasonable allowances for such items as have been named, it seems safe to infer that the mining and metallurgical industry of this State accomplished in 1901 a substantial progress.]

Jan 1, 1902

By Güney

"An investigation carried out to determine the tendency of coals to heat spontaneously in terms of time-temperature curves coupled with the resulting oxidation products in an adiabatically controlled laboratory setup is described. Tests were made at differing moisture conditions, including oxidation and also oxidation with either adsorption or desorption of water vapour on coal.From the experimental evidence, there is reason to believe that the oxidation of coal, although an important factor, is not the predominant one in the development of spontaneous heating. In addition to the temperature increase in coal and the gaseous products evolved due to auto-oxidation, the process is accelerated by adsorption and retarded by desorption of water vapour on coal."

Jan 1, 1971

The Technical Study Panel on the Utilization of Belt Air and the Composition and Fire Retardant Properties of Belt Materials in Underground Coal Mining (hereafter referred to as the Panel or the TSP) was established by Section 11 of the Mine Improvement and New Emergency Response Act of 2006 (MINER Act). The Panel was charged with providing “independent scientific and engineering review and recommendations with respect to the utilization of belt air and the composition and fire retardant properties of belt materials in underground coal mining.” The TSP was impaneled by the Honorable Elaine L. Chao and commenced its work on January 9, 2007. At this first meeting, Mr. Richard E. Stickler, Assistant Secretary of Labor for Mine Safety and Health, asked the Panel to report on many issues including how recent technological advances could be applied to atmospheric monitoring systems, point-type heat sensors, current state of fire-resistant vs. fireproof belt materials, and belt fire suppression systems to improve miner safety. In addition, Mr. Stickler asked the Panel to review belt air velocity limitations. The Panel members attended 12 days of public meetings over a nine-month period. Three of the public meetings were scheduled for the Panel to hear from technical experts and those persons or organizations interested in providing input. The meetings were held in Coraopolis, Pennsylvania with emphasis on belt fires, belt maintenance, belt flammability and toxicity, ventilation, and escape issues; in Salt Lake City with emphasis on ground control and convergence issues; and in Birmingham with emphasis on fire detection, sensors and atmospheric monitoring systems. National Institute for Occupational Safety and Health (NIOSH) researchers, Mine Safety and Health Administration (MSHA) personnel, representatives of the major belt conveyor manufacturers and a representative of the National Mining Association provided discussions at the Coraopolis meeting. In Salt Lake City, Utah, MSHA district managers and ventilation specialists, a member of the Aracoma Mine No. 1 investigation team, a representative of the Bureau of Land Management, and industry and consulting representatives of the Utah Mining Association and the Colorado Mining Association made presentations. In Birmingham, Alabama, atmospheric monitoring system representatives, NIOSH researchers, representatives of coal mining companies, and UMWA workers from two Alabama mining companies made presentations. In addition, a staff member of The Center for Regulatory Effectiveness also presented comments to the Panel. In conjunction with the meetings in Salt Lake City and Birmingham, three-member subcommittees of the Technical Study Panel made field visits to the Skyline Mine, the Aberdeen Mine, and the Jim Walter Resources Mine No. 4. The mine visits were scheduled to see first-hand the mining conditions under which belt air was being utilized as an additional source of intake air for working sections.

By H. O. McDonald

The Bureau of Mines reviewed the chemical vapor deposition (CVD) literature of the group IVB, VB, and VIR elements. This review was utilized in the Bureau's research to provide erosion-, abrasion-, and corrosion-resistant coatings for valve components used in coal gasification units. This report attempts to bring together the many CVD references that have been published since 1966. Each of the group IVB, VB, and VLB metal coatings were reviewed, and some of their preparation methods, uses, and properties are given. A total of 160 references were found for the nine elements. Isotope separation, stronger steels, solar absorbers, alloys, superconductors, optical fibers, and coatings to increase the life of materials are some of the new uses for CVD.

Jan 1, 1979

By Joan Weinberg

The real gross national product (GNP) advanced at a annual rate of 3.1 % during the second quarter, following a revised 3.4% increase in the first quarter (see table 1). Export growth continues to play an important role in the rising output. Combined with the decline in imports, it resulted in a noticeably improved trade position. Imports of consumer goods, including automobiles and food, fell while exports rose. Imported cars have been losing ground to domestic cars. The foreign car share of the U.S. market fell from 36% in October 1987, to 29% in May 1988. Business spending for new plant and equipment contributed strongly to the GNP increase. Equipment purchases, particularly of computers, rose at a 14.8% annual rate, following a large first-quarter gain. Purchases of structures rose 11.8%. The other key component of business spending, change in business inventories, declined from the first quarter. Inventory buildup in late 1987 had been considered excessive.

Jan 1, 1988

By S. H. Ash, J. J. Forbes

Probably the newest thing in mining safety, or safety for mines, is the apparent dissatisfaction on the part of the mineral industries, as represented by both management and labor, and the general public of the Nation, with the safety record of the mining industry. This is reflected by published comments and papers in the technical press;l-9 in labor periodicals,10,11 in popular journals and periodicals,l2, 13 and in the daily press; also by discussions of the Safety Committees sponsored by the National Safety Council,9, 14-15 the American Mining Congress,l.l6 the American Institute of Mining and Metallurgical Engineers,2,4 the Mine Inspectors' Institute of Amerthe Coal Mining Institute of America,5 19 the American Standards Association, and others.20.21 Mining safety is a joint problem of management and the individual workman. Safety is not attained and will not be attained solely by laws, decrees, and commands because, if it could be done in this manner, acceptable mining safety would have been achieved long ago by the individual states in our Nation and by the nations abroad. The best safety performance is found at plants where management provides a safe environment for the workers; where supervision is efficient and super- visors, others concerned with promoting safety, and the individual worker know through training, experience, and personal contact the safe and unsafe practices of their field; and where the trained individual worker has become safety-minded by experience, quiet influence, unconscious suggestion, and personal guidance. Despite what may be said to the contrary, progress has been and is being made in mining safety. This is shown in Fig 1 to 4. It is beyond the scope of this paper to give possible reasons for the valleys and peaks in the fatal-injury rates. Some recent factors that appear to be contributing to the improvement in these rates are briefly discussed. Aside from mining equipment, "what's new in mining safety" for some mines has been in effect or was tried by others long ago. A safety pro- gram is a living thing; as such, it must be vitalized and continuously fed with enthusiasm, constructive action, and improvements. Because safety is concerned with human conduct, it is necessary to practice safety at all times; if not, it is soon forgotten, and accidents occur. Mining-safety Records The large employment and production concerned with anthracite contribute much to the mining-safety records of the mineral industry. Approximately 81,000 persons are. employed in this industry having mines concentrated in an area of 480 square miles in northeastern Pennsylvania. Because of the achievement of the anthracite industry in safety during 1948, the other branches of the mineral industry can profit by a study of what has been done to achieve that record. Where one mineral is produced by other large groups having methods of mining that are similar in many respects to the anthracite-mining methods, an achievement in such a large industry is important. Salient factors concerned with safetye in the anthracite industry are: no radical change has occurred in the mining-safety regulations pertaining to anthracite mines. Because anthracite mining is a branch of the coal-mining industry,

Jan 1, 1950

By ALFRED D. FLINN

ENGINEERING COUNCIL has passed, not out, but upward! Therefore, its recent wake was conducted by itself as a joyful occasion somewhat in advance of its official demise. Council held its last meeting in Washington, Dec. 16, 1920. Business was transacted with dignified gravity in the forenoon. During the afternoon calls were made upon the chiefs of technical bureaus of the Government: the Chief of Engineers, U. S. Army; Chief of Yards and Docks of the Navy Department; Director of U. S. Reclamation Service; Director of U. S. Geological Survey; Director of Bureau of Mines. The Council pronounced them, each and all, able men and true. But what of the evening? Well, there was a dinner at the Washington Hotel. Twenty-six men gathered around a flower-strewn table-not a casket. As guests, there graced the festive board the hosts of the afternoon calls, and a number of members of the new American Engineering Council. The body about to be apotheosized-otherwise known as Engineering Council-was both jocular and reminiscent. Rewards were bestowed and appreciations expressed. To the man who had for three long years borne the burden of chairmanship and whose financial recklessness made possible the Washington office and the movement for a National Public Works Department, the following "note," duly engrossed and signed, was given, accompanied by "The Song of the Council Crew."

Jan 1, 1921

By K S. Smith, J Woodhead, K Olson Hoal

Mineralogy is the link between ore formation and ore extraction. It is the most fundamental component of geomet programs, and the most important aspect of a life-of-project approach to mineral resource projects. Understanding orebodies is achieved by understanding the mineralogy and texture of the materials, throughout the process, because minerals hold the information required to unlock the value they contain. Geomet mineralogy programs absolutely require the appropriate expertise and at least three steps of mineral characterisation prior to using semi-automated or other methods: field examination, thorough core logging, and optical microscopy. Economic geological inputs for orebody characterisation are necessary for orebody understanding, and are exemplified by current research in the Zambian Copperbelt, where revised sequence stratigraphy and understanding of alteration, metasomatism and metamorphism can be used to predict topical issues at mine sites. Environmental inputs for sustainability characterisation are demonstrated by recent work on tailings from the Leadville, Colorado, USA area, including linking mineralogy to water quality issues. Risk assessments need to take into account the technical uncertainties around geological variability and mineral extractability, and mineralogy is the only metric that can be used to make this risk contribution.CITATION:Olson Hoal, K, Woodhead, J and Smith, K S, 2013. The importance of mineralogical input into geometallurgy programs, in Proceedings The Second AusIMM International Geometallurgy Conference (GeoMet) 2013 , pp 17-26 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 29, 2013

By F. X. Tartaron

This report describes work done by the Bureau of Mines to simplify the design and operation of the vortex cone, a new device for prerefining blast furnace iron. Three new apparatus arrangements were tested. Results with one of these arrangements average 74.2 pct silicon removal and 61 pet oxygen efficiency (disregarding removal of carbon and manganese).

Jan 1, 1965

By K. U. Kainer

Magnesium and its alloys as the lightest available construction metal offer a wide range of opportunities for the usage in transportation industries, especially Magnesium wrought alloys with their improved mechanical properties show a high potential for structural applications, While magnesium cast components have found their application the interest is now spreading to wrought alloys due to the possibility to get even more homogeneous and better properties compared to cast parts, Therefore alloy and process development especially for extruded and sheet material is a main concern to enhance the application of Magnesium wrought alloys, Castings are still form the majority of applications of magnesium alloys, although efforts to develop adequate wrought alloys have increased, In the presentation, the alloy requirements for processing of cast and wrought alloys will be discussed, The various processing routes and alloy compositions result in specific microstructures and properties which determine the potential use of these alloys, Today, the spectrum of available alloys covers standard alloys as well as alloys for use at elevated temperatures, The trend will be to further diversify the alloy compositions and to improve the alloy properties, Areas of concern still remain the wrought processing and the high temperature (creep) and corrosion properties of magnesium alloys, Examples of recent developments in these sectors will be given, The presentation will also provide an overview of the historical and current use of magnesium and an outlook on future applications.

Jan 1, 2006