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By George J. Conroy

Techniques for locating trailing-cable faults are discussed, particularly those techniques suitable for use in underground coal mines, which have been the subjects of Bureau of Mines research. The discussion concerns precautions and suggestions for locating faults, rather than detailed descriptions of apparatus.

Jan 1, 1979

By John C. Machisak

THE INJURY data and related employment experience of the coking industry in the United States for 1955 arc presented in this publication under the following general sections: (A) General Injury experience: Tables 1 to 9: Contain current and comparable data on operating statistics, number and classification of injuries, injury-frequency rates, and accident agencies involved in causing injuries. Data are tabulated for the industry as a whole, for each typo of oven: and for the States in which coke is produced.

Jan 1, 1958

By Ted C. Briggs

Equations for the elastic pressure distortion of the volumes of a Burnett compressibility apparatus are developed and presented in this report for volumes under internal and external applied pressures. An experimental method for the determination of the external pressure distortion coefficients is presented. Young?s modulus and the internal-pressure distortion coefficients are computed from the experimentally determined external-pressure distortion coefficients. The temperature dependence of the pressure distortion coefficients and of Young's modulus is evaluated for the temperature range 0° to 80° C.

Jan 1, 1968

By C. L. Karr

The U.S. Bureau of Mines is optimizing the design of an air-sparged hydrocyclone. This report summarizes the initial stage of the project-the prediction of collision efficiencies for use in a comprehensive air-sparged hydrocyclone model. The equations of motion are presented in nondimensional form and solved numerically for a small spherical particle passing around a larger bubble in an infinite fluid under the influence of a strong force field. Collision efficiencies are determined from the calculated particle trajectories for values of Stokes' number, K, between 0.01 and 100 and for values of the nondimensional force, W, between 0.0 and 100. These large values of K and Ware needed to model high-performance flotation devices like the air-sparged hydrocyclone; solutions for the required K and W values have not appeared in the literature prior to this study. Effects of changes in particle-to-bubble radius ratio are considered for both viscous and potential flows. The results help predict the improved recovery of fine particles when flotation is performed in a strong force field.

Jan 1, 1990

By R. Unger, L. Mallett

The use of virtual reality (VR) technologies to train miners is an evolving area in research and development. In July 2006, representatives of 14 international organizations met to discuss current VR-related efforts and explore ways to employ VR in the future. This paper gives an overview of the various approaches presented at the meeting and discusses directions for future implementation. An example of a training package that teaches mine map-reading skills is presented. The meeting was the first step to building collaborations for furthering VR applications for mining. Planning has begun for a 2008 meeting open to broader participation. Disclaimer: The findings and conclusions in this report are those of the authors and do not necessarily represent the views of the National Institute for Occupational Safety and Health.

By Fun-Den Wang

A two-dimensional plane strain analysis by the stiffness matrix method was used to analyze two basic pit slope configurations. The magnitudes and the directions of stresses are given for a V-shape and for a flat-bottom pit with the slope angle varying from 30° to 90° at 10° intervals, Stress effects due to irregular pit configuration or to in-situ forces are discussed. Equations of similitude for gravity loading are given. Expressions are also given for the stresses at the toe as a function of slope angle. Procedures are given for finding the stresses in any geometrically similar pit slope of different dimensions and material properties from the stresses and equations presented in this report. Numerical results show that the V-shape pit slopes have lower stresses than the flat-bottom pit slopes; hence, they are inferred to be more stable.

Jan 1, 1970

By H. C. Miller

[California's sensational rise to supremacy as an oil-producing State in 1923 was accompanied by a loss of 62 lives. These 62 deaths were from oil-producing accidents alone and do not include fatalities at the refineries, on tankers, or on any work not directly connected with the drilling for and the production of oil. The number of facilities for 1923 was 82 per cent greater than in 1922, the next most fatal year, with a record of 34 lives lost. The data submitted in Table 1 show that for the calendar years 1917 to 1923 inclusive, an average of 4.74 million barrels of oil were produced per Vitality in the California oil fields. On this basis, the record for 1923, hough a trifle below the average, shove up slightly better than that for 1922.]

Jan 1, 1924

By Larry R. Powell

As part of the Bureau of Mines effort to establish a comprehensive subsidence data base for subsidence technology development, subsidence and related data are being compiled for various mining, geological, and environmental situations. This publication presents data for a longwall mining operation in the Northern Appalachian Coal Region. Vertical displacements and relative face positions are tabulated for 110 subsidence monuments. Measurements were taken twelve times during the eight months it took to mine the panel. Brief physiographic and geological descriptions of the mining site are presented along with a general account of the mining and subsidence monitoring methods.

Jan 1, 1981

By Robert H. Lambeth

The Madison RARE II study area has four prospects with identified resources. These are listed in table 1 and are described in the following text. A high potential for Sillimanite exists at the Placer Creek occurrence (fig. 1, no. 7) and potential for phosphate rack in all areas underlain by the Phosphoria Formation. Some prospects exhibit minor potential for copper, lead, zinc, silver, and gold in the southern portion and very minor potential in the northern portion. Deposits in the northern end also have low potential for rare earth, asbestiform anthophyllite, or kyanite group minerals (including sillimanite).

Jan 1, 1982

By William A. Hoffman

In This Chapter [MSHA regulations for coal mines MSHA regulations for metal/nonmetal mines OSHA regulations for tunnel construction Types of respirators used in mines and tunnels Filter materials and filter efficiencies Donning, seal checking, and maintenance Filter service life and Respirator information resources] In many cases, engineering controls are not adequate to achieve satisfactory dust levels, so respirators must be used. This chapter explains the Federal regulations governing the use of dust respirators in mines and tunnels and describes the most common dust respirators used. Filter materials and filter efficiencies for respirators are discussed. This chapter also gives some guide-lines for respirator use and recommends sources for more dust respirator information. Respirator effectiveness in reducing dust exposure usually exceeds the effectiveness of most engineering control methods. RESPIRATOR REGULATIONS [Different regulations govern respirator use in coal mines, metal/nonmetal mines, and tunnels under construction.] Coal mines under Mine Safety and Health Administration (MSHA) jurisdiction. Coal mine operators are required to meet dust standards using only engineering control methods. Typical engineering control methods include ventilation and water sprays. Respirators are not regarded as an engineering control method, so respirators cannot be used in lieu of engineering controls.

Jan 6, 2003

By V. E. Erwin, W. W. Adams

"INTRODUCTION This report presents statistics of accidents at coke ovens in the United States during the calendar years as 1933, the twenty-first year for which data of this kind are available, 1913 being the first year for which accident reports were collected from the operating companies by the Bureau of Mines. The present report is presented in mimeograph form because insufficient funds are available for printing it. The first report of the Bureau of Mines that contained statistics of accidents for the coke-mining industry in the United States covered the two calendar years, 1913 and 1914. While the figures presented therein related both to beehive and by-product ovens, the original returns from the operating companies were not classified so as to permit the presentation of accident statistics for each class of ovens separately. Beginning with 1915, the accident reports from the operating companies have shown the general type of ovens to which the reports related; therefore, since that year, separate statistics for each of the two classes of ovens have been given in the Bureau's yearly reports of accidents at coke ovens.The coke-making industry in the United States established a safety record in 1933 almost equal in merit to that which it achieved in 1932, when the accident-frequency rate was the lowest and therefore the most favorable that the industry has known. Credit for the achievement is due almost entirely to companies operating byproduct ovens. (See table 8.)"

Mar 1, 1935

By David P. Lindroth

The heat content above 25.0° C up to 1,000° C was measured for six rock types: St. Cloud Gray Granodiorite, Holston Limestone, Sioux Quartzite, Rockville Quartz Monzonite, Salem Limestone, and the basalt at Dresser, Wis. The calorimetric data were obtained with an isothermal jacket-copper block calorimeter. The experimental heat content data for each rock type are presented, along with specific heat data obtained from the temperature derivative of the heat content. For the six rock types the maximum deviations of the specific heats at a given temperature were within 10 percent below 575° C and within 34 percent above 5750°C. The increase in the values of specific heat range from a minimum of 13 percent for the basalt at Dresser, Wis. (temperature range, 100° to 1,000° C) to a maximum of 46 percent for Holston Limestone (temperature range, 100° to 870° C).

Jan 1, 1971

By Oliver Bowles

"Waste Granite in the Barre, Vermont, District: Waste in the great granite center at Barre, Vermont, consists of three types of material, the rough blocks rejected at the quarries on account of imperfections, the chips or spalls resulting from trimming and dressing at the cutting plants, and the granular and pulverized material from the dust collectors. The waste piles at the quarries of are immense proportions and constitute a serious handicap to quarrying in that they cover up good rock deposits, and are also so large that waste disposal becomes more and more expensive. The problem of utilization of such waste material is a topic of keen interest to all granite producers.Barre is not situated on a water route, and thus transportation costs prohibit the shipment of waste blocks for rip rap or ballast. Crushing plants use a small amount of this material for road construction, but aside from this, the waste is practically valueless.Investigators of waste utilization problems are awaiting with interest further information concerning an enterprise undertaken at Montpelier, Vermont, to utilize crushed granite for the production of brick similar to sand-lime brick. Granules of granite are mixed with lime, moulded, and hardened under steam Pressure, The brick produced are said to be of excellent quality for structural Purposes.There seems to be no logical reason why waste granite could not be utilized for the manufacture of building stone, and paving blocks, for many of the defects which condemn a stone for monumental purposes are not at all detrimental for building or street paving. F or the most part, monumental stone workers are not particularly interested in other branches of the granite in-dustry, and a combination of industries such as that suggested"

Jan 1, 1920

By W. D. Walker

This information circular is offered to the coal-mining industry for use as a guide in selecting, placing, and caring for fire-fighting equipment in coal mines. Its purpose is to suggest minimum requirements for fire protection underground, and it is presented with the hope that it will aid in establishing adequate standards that will provide reasonable protection against underground fires in coal mines. Potentially, a coal mine is a hazardous fire area. Coal itself is a combustible substance, easily ignited. In addition, large quantities of other combustible materials must be present in the area of operations; these include materials for roof support, track ties, doors, ventilation stoppings, lubricants, etc.

Jan 1, 1953

By E. Chin

Natural gas was the only economically significant mineral produced. A significant amount of the gas output was consumed in the production of nitrogen fertilizer and electric power. Proved reserves of natural gas were abundant and at least sufficient to supply most of the country's industrial and domestic needs for many decades to come. Other mineral production was of little importance to the Bangladesh economy, although there were prospects for developing some of the nonmetallic minerals. The flat river-delta terrain comprising nearly all of Bangladesh made the potential for discovering major, economically exploitable mineral deposits poor. The deep sediments, however, have good potential for crude oil or additional natural gas discoveries.

Jan 1, 1985

By A. W. Effinger

The Bureau of Mines used regression analysis and applied statistical methods in an effort to rationalize the results of an experiment examining the effects of certain variables on carbon deposition in a reservoir for thermal recovery of petroleum. Although none of the 15 trials of the original experiment resulted in the response of weight-percent of carbon regarded by the experimenter as adequate, values calculated using canonical analysis in two trials yielded responses 33 and 54 percent higher than the minimum acceptable figure. The actual responses differed by less than 3 and 6 percent, respectively, from the predicted responses. Methods are described for defining a path of increasing response based on the minimum point and the response surfaces and for defining a set of values for the parameters in question, which result in increased response, A detailed explanation of the mathematical process used in this analysis is presented in the appendix for ease in computer programing the technique.

Jan 1, 1970

By BUREAU OF MINES

The approval of the U. S. Bureau of Mines when granted to a manufacturer for a gas mask is a certification that the particular device has been submitted to the Bureau of Mines for inspection and test and has been found to meet that bureau's published minimum requirements for safety , durability , and satisfactory performance . Any de- Gas masks are approved by the Bureau of Mines only as a complete unit or assembly of parts , as canister , facepiece and harness . This is in order that responsibility for rigid adherence to the bureau's requirements may be definitely located and not divided . vice marketed under this approval must be a unit composed of parts identical in detail of design , assembly , workmanship , and quality , and produced under the same control and inspection as the original device to which approval has been granted . The particular parts which comprise the approved assembly are designated in a letter to the manufacturer at the time the approval is granted . In recent years they are also specified in the approval plate authorized for use in connection with the sale of the device . Each part permitted in the assembly is legibly marked by name or number for the guidance of users of masks in ordering and identifying approved parts when making repairs , and thereby maintaining their equipment as an approved device . In view of the foregoing , any change in the design of parts or deviation from the permitted assembly of parts would violate the conditions under which approval was granted and the device would not be considered as meeting the approval requirements of the Bureau of Mines . The U. S. Bureau of Mines has been frequently requested to interpret the approval status of a gas mask assembled from parts which have separately met its requirements as components of two or more approved devices but which in the form of a complete unit has not been submitted for tests or been granted approval . Responsibility for the elements and for their proper assembly is in such case divided . Such assembled units have no status as permissible equipment under the Bureau of Mines system of schedules . The reasons underlying this policy are that the approval is granted only to some one who assumes responsibility for the whole and that the details of assembly and coordination of parts are considered to be important to the satisfactory performance and safety of the device .

Sep 1, 1932

By Charles L. Kimbell

The concept of data availability must be addressed, because there are perceptible changes from year to year, and the availability of accurately reported, precisely defined statistics and nonstatistical information provides the only sound basis for analytical studies required for government policy planning or industry market analysis. As the countries of Eastern Europe and the former U.S.S.R. undergo the transition from centrally planned economies to market economies, there has been a perceptible increase in information availability for rather obvious reasons. Any industrial operation seeking economic assistance from Government and/or private sources outside the country in which the facility is sited must provide some appraisal of its operations at the time it seeks assistance, as well as some information on previous performance to serve as tools in evaluating its potential under the proposed development scheme for which it seeks financial assistance. Additionally, there was growing governmental recognition that concealment of much of the national mineral production, trade, and consumption data for purposes of national military and/or economic security probably never was very successful, never was really necessary for most commodities, and certainly proved unnecessary with the end of the so-called cold war. Indeed, the long-term unwillingness to publish uniform statistical series of reliable,

Jan 1, 1993

By John H. Scott

At the request of the Mine Safety and Health Administration, U.S. Department of Labor, the Bureau of Mines evaluated the model BT 300 C-D blasting machine tester, manufactured and distributed by Research Energy of Ohio, Inc. (REO), to determine whether the tester performed as stated by the manufacturer and responded satisfactorily to electrical faults introduced into the blasting machine circuit. Tester readings were recorded for 13 blasting machines and for 12 circuits constructed to simulate the electrical parameters of actual machines. The tester readings were acceptable for all of the blasting machines, although the switch position assigned to one machine produced an off-scale reading. The tester responded satisfactorily to the simulated circuits and detected serious voltage or capacitance faults when they were introduced. However, it did not respond accurately to certain resistance faults. Temperature tests were also made, and the tester performed equally well at temperatures of 20°, 42°, and 81° F. This tester was judged a useful accessory for field checking blasting machines for defective batteries and capacitors, despite its limitations. It is recommended that the tester manufacturer specify the lowest acceptable reading at which a blasting machine may be used and below which the blasting machine should be returned to the laboratory or manufacturer for maintenance.

Jan 1, 1981

By Forrest T. Moyer

OVERALL data for 1963 on injury experience and the levels of employment, worktime, and operating activity of the mineral industries are shown in the statistical tables of this chapter. The general groupings of the industries are presented in greater detail in Volumes I and II of the Minerals Yearbook. A corresponding chapter in Volume I contains additional breakdowns of the data on metal, nonmetal, sand and gravel, slag, and stone mines and quarries together with separate information on the related processing mills and plants including primary nonferrous smelters. The more specific information on the anthracite and bituminous-coal, petroleum and natural gas, peat, and natural asphalt industries is given in the similar chapter of Volume II. Injury and employment data were collected from coal producers on the mandatory basis required by the Federal Coal Mine Safety Act (30 U.S.C., sec. 455). Producers of all other minerals (fuel and nonfuel) voluntarily reported the requested injury and employment data. The figures for 1963 are preliminary except for anthracite, coke, petroleum and natural gas, native asphalt, and slag which are final. Data for earlier years are final. The figures represent full coverage for all industries except the oil and gas industries for which coverage is not complete, particularly with respect to small companies.

Jan 1, 1964