Search Documents

By Charles Vaught, Michael J. Brnich, Roberta A. Calhoun

This document contains most of the materials needed to use the exercise. The main part of the document is the instructor's copy. It tells how to use the exercise, presents the objectives, the master answer sheet, the scoring key, and discussion notes to be used following the exercise. The next section summarizes results from field tests of the exercise, and reports the miners' evaluation of the activity. The last part of this document is three appendices. Appendix A is the exercise problem booklet. This booklet can be duplicated locally. The booklets are reusable. One is needed for every person in the classroom. Appendix B is the answer sheet. Copies of this answer sheet must have the latent image (invisible) ink answers that appear in Appendix C printed on them.2 Answer sheets are consumable. One is needed for each person or each small group of persons who work the exercise. Exercise Summary Read this section first. It determines if the exercise is appropriate for your classes. If you choose to use the exercise, examine the table of contents and review the remainder of this document. Type: Latent image Audience: Underground coal miners Length: 9 questions (30 minutes for administration and 30 minutes for discussion) Skills: Mine fire escape strategies/procedures Use of emergency breathing apparatus Knowledge of sensations experienced when wearing breathing apparatus Communication Location: Underground coal mine section, average 60 inch seam height Problem: You are the section foreman on the 17 Left longwall development section at the Paula Ann No. 3 mine. The section has been driven about 4,000 feet from 4 West Mains. One of the shuttle car operators took a call from the fireboss saying that there was smoke from an unknown source coming into your section. You attempt to contact someone to find out where the smoke is coming from but get no response. You assemble the crew and start riding out of the section on the mantrip when you encounter heavy smoke. At this point, you decide to take your crew and travel on foot in the belt entry that is on a neutral split of air. After traveling about 6 crosscuts in the belt entry, you encounter heavy smoke at which time you and your crew don your person-wearable SCSRs (PWSCSR). After donning the apparatus, you and your crew continue traveling outby in the belt entry. Near the mouth of the section, one miner in the group starts to have trouble breathing from his SCSR. Because breathing resistance is increasing with the length of time the apparatus is worn, the miner is "outbreathing" the device since his oxygen requirements are greater that what the PWSCSR can supply. Although you slow

Jan 10, 1999

By H. E. Dresch

This report summarizes the work accomplished under Bureau of Mines contract H0188068. The contract required design and construction of a high voltage (7.5 KV) explosion proof cable connector for use on underground coal mine drag cables. A connector was constructed with elastomeric phase insulators that provide insulation shielding throughout the connector length. Connector housing was made of flame resist-ant cast poly urethane with no exposed metal components. Electrical and mechanical testing of the completed coupler resulted in satisfactorily meeting most of the design testing requirements.

Jan 1, 1981

By C. M. McCulloch

The methane content of virgin bituminous coalbed can now be measured accurately in the field with exploration core samples from vertical boreholes. The gas content of the coal per unit weight can be used either to design a mine ventilation system or to determine if degasification of the coalbed will be necessary before mining, and to determine the gas resources in the coalbed. The equipment necessary to conduct the test costs less than $50. The gas con-tent of the coal in place in the ground is determined by summing the gas lost from coring, gas measured during desorption, and the residual gas in the coal. Upon removal from the borehole, the core sample is placed in an airtight container and des orbed for several weeks until the desorption rate is below 0.05 cm3/g for 5 consecutive days. The gas lost from the core while it was being cored and the residual gas are estimated by a new graphical method. The amount of gas remaining depends upon whether the coal is friable or blocky. Friability appears to relate to the depth of the sample below the surface, fixed carbon percentage, Hardgrove grindability index, and proximity to tectonic disturbance. Friable coals emit nearly 96 pct of the total gas during desorption whereas a blocky coal emits only 60 pct of its total gas. Coalbeds that are ill defined as to their blocky or friable nature must be tested in the laboratory for unambiguous analysis.

Jan 1, 1975

By M. J. Jackson

MIGRATOM is a third-generation PC-based computer program developed by the U.S. Bureau of Mines for geophysical tomography. Like its predecessors, BOMTOM and BOMCRATR, MIGRA TOM was developed to enable users to address a variety of mining-related problems by mathematically reconstructing the distribution of physical properties in a rock mass, using measurements of travel time or amplitude of wave energy propagated through the rock mass. Examples of applications include lithologic characterization, fracture detection, fluid monitoring, stress evaluation, and blast assessment. The resolution and accuracy of tomographic reconstructions generally depend very strongly on the geometry of source and receiver locations. In many practical applications, such as cross-borehole tomography, limited coverage results in nonunique reconstructions. MIGRATOM follows the precedent of BOMTOM and BOMCRATR in allowing the user to constrain the inversion, in order to reduce the nonuniqueness problem. A new approach to application of constraints implemented in MIGRATOM is based on fuzzy logic techniques. Refraction of wave energy is modeled in MIGRATOM using an approach based on Huygens' Principle. Propagation of a continuous wavefront is modeled as a constructive interference phenomenon, which obviates the shadow-zone problem that affects conventional ray-tracing calculations. MIGRATOM has been tested with both synthetic and field data sets.

Jan 1, 2010

By Pamela J. Watson

This report presents a Bureau of Mines literature survey that provides a data base useful for current and future studies in the area of chemically enhanced drilling and cutting. Publications describing laboratory testing and field studies of drilling and cutting with chemical additives are reviewed. Significant results are summarized and tabulated by rock or material type and also by chemical additive, with extensive references. Selected studies related to fluid-enhanced processing or material testing are summarized in the appendixes.

Jan 1, 1985

By Joan K. Kuenzi

This Information Circular brings together for consideration recommendations from U.S. Bureau of Mines research in the area of surface mine mobile equipment maintenance for the period 1982 through 1991. It updates the 1982 contract report by Baker and Alves that formed the basis for much of the work described in the present report. Recommendations for hazard abatement during work on mobile one equipment are presented and stem from the results and recommendations of the research in two areas: (1) equipment and workplace hazard reduction, and (2) management of maintenance information. Recommendations included in this report apply to both the operators and maintainers of mobile mining equipment as well as to the manufacturers of that equipment.

Jan 1, 1995

By Charles L. Kimbell

Comprehensive world mineral industry investment data do not exist, but limited material published on aggregates of in vestment in some elements of the world mineral industry suggest a continued up-turn in the investment level, at least in market economy countries in 1989. Steel industry investments in Organization for Economic Cooperation and Development (OECD) countries are not yet available for 1989 but, as shown in table 6, increased by 22.1% in 1988, after showing a decrease of 5.2% (revised) in 1987. The pattern of investment ups and downs varied during 1988 within country blocs and economic alliances showing no particular trends. Investment in the steel industry by the United States increased by 58.3% between 1987 and 1988 and was 1 1.9% higher than the previous highest amount invested during the 1984-88 period but was still 41.5% less than the amount invested in 1983. Investment in the steel industries of the European Coal and Steel Community (ECSC) dropped again in 1988 from the revised amount for 1987, which became the first drop after several years of steady growth in what became the expanded ECSC in 1986. This drop in 1988 was the result of lower investments by Denmark, France, the Federal Republic of Germany, Ireland, Italy, Luxembourg, the Nether- lands, and Spain, investments grew or remained level in Belgium, Portugal, and the United Kingdom in 1987 and 1988. A decrease in investment in the Canadian (-26.6%) steel industry was offset by in- creases registered by the members of the European Free Trade Association (EFTA) of 31.7%, by Japan of 19.8% by Turkey of 22.4%, and a slight increase by the nations of Latin America. If data for the world steel industry as a whole, including those of the centrally planned economy countries, were available, the same pattern presumably would be shown as that reported; that is, it would remain fairly stable, with increases in some countries being offset by decreases in others. However, the lack of comprehensive information on the centrally planned economy countries makes it impossible to determine whether the overall trend was up or down despite recorded increases or decreases in production of the materials involved. Preliminary data show that investment levels in industries dealing with the production and/ or processing of mineral commodities for

Jan 1, 1992

By Albert L. Toenges, Louis A. Turnbull, EDWARD L. FISH, JOSEPH J. SHIELDS, James J. Dowd

The stripping of coal with mechanical. equipment has progressed since the introduction of the first steam-powered shovel for the retóval of overburden at a mine in Pittsburg, Kans., in 1877...From the smart steam-powered shovels with dippers of less than a cubic yard capacity, small digging radius, and shovels that required manual moving, the trend has been toward large-capacity machines. Steam as power has been replaced largely by electricity, gasoline, and Diesel fuel, and dipper capacity as great as 35 cubic yards has been attained. Shovels and drag lines are self-propelled and revolve through 360°. The cost of these large-capacity modern machines is great, and in order to assure the return of the investment during the life of the property the reserve of coal in the area to be mined must be large;" Many comparatively small areas of coal suitable for strip mining exist, but these areas probably could not be mined, profitably with this large equip- ment. Therefore, heavy equipment has not been used in small areas because of the high cost in place of this equipment, the time and Atpense required to transport the machines to the mine site, and the construction of power lines if the machines are electrical powered.. Scrapers and light excavating equipment ane mobile, and the investment cost is not high. These units have been used in sirring the coal in small areas. A study to determine the methods in, yogue, and economic considerations involved in the use of such equipment was undertaken, and the information obtained is discussed in this report.

Jan 1, 1947

By F. E. Block

The reaction between calcined dolomite and ferrosilicon has been studies with the aim of developing a continuous process for magnesium production. Small-scale tests were made in vacuum retorts similar to those used in the vacuum retort process as developed by Pidgeon (1)2/ and operated during the period of World War II in several Government-owned plants. Factors investigated with respect to the silicon efficiency were the reaction temperature, reaction time, amount of excess dolomite in the charge, and effect of adding sodium silicate to the charge to serve as a binder. Additional laboratory tests were made to study the reaction at elevated temperature but at atmospheric pressure. Silicon efficiencies exceeding 80 percent were found to result when operating in the temperature range from 1,750° to 1,800° C. for periods of 20 to 30 minutes.

Jan 1, 1956

By C. C. Blade

"This report on the properties of motor fuels sold through service stations ni the Unietd States is a continuation of a series of reports made in accordance with a cooperating agreement between the Coordinating Fuel Research (CRF) Committee of the Coordinating Research Council (CRC)3/ and the Bureau of Mines of the United States Department of the Interior. The first of these reports presented data on motor gasolines sold during the winter of 1935-36.4/ Further reports were issued describing motor gasolines sold during the succeeding summers and winters to and including the summer of 1941.4/ No reports were made on motor gasolines sold during the winter of 1941-42 and during the summer of 1942. However, starting with the winter of 1942-43, the semiannual reports were resumed.4/The present report presents analytical data for 1,381 samples, representing the products of approximately 75 companies. Most of the samples represented in this report were secured during July and the first half of August, 1945. As in previous surveys, the companies covered by the survey include both large and small suppliers. Conforming to former reports, the data cover three groups of samples – regular-price, premium-price, and third-grade gasolines.As the number of analyses submitted for samples of third-grade gasoline are not considered adequate to represent this type of motor fuel, data for the analyses have not been averaged, but the individual items are tabulated. The number of samples, items and brands comprising each group is as follows: Regular-price, 733 samples, 229 items, and 57 brands; premium-price, 504 samples, 197 items, and 56 brands; third-grade, 84 samples, 28 items and 12 brands. The meanings of these terms as sued in the surveys are as follows:"

Jan 1, 1946

By Carlton E. Brown

Brown and Yant6/ recently described a microprojection method for determining the particle-size distribution and number concentration of samples of dust collected from the air by such samplers as the Owens jet dust counter7/ and the thermal precipitator8/. This method was developed to obviate or reduce the eyestrain consequent to the regular filar-micrometer method9/ and to save time and work. The article stated that work was in progress on a microprojection method for courting impinger dust samples; this article describes the method developed. ACKNOWLEDGMENTS The assistance of the personnel of the Ventilation Department of the Anaconda Copper Mining Co., Butte, Mont., in developing this method and particularly in suggesting a suitable material to use for the microprojector screen is sincerely appreciated. Much of the work was done in the laboratory of the Anaconda Copper Mining Co. on samples collected in Butte mines during a cooperative study with this Bureau.

Jan 1, 1938

By A. J. Kraemer

This paper is the second and concluding report of the results of the Bureau of Mines' twenty-second semiannual survey of motor fuel marketed in the United States. The first paper Was published as Report of Investigations 3063 and reported data relating to gravity, vapor pressure and distillation range of the samples. The present paper deals particularly with results of the determination of copper strip corrosion (method 530.22), color (method 10.11), sulphur content by the lamp method, copper dish evaporation residue (method 530.1), and "gum" content as given by the steam-oven method as developed by the Bureau of Mines. The price at the time the sample was taken and the tax are also stated for each sample. The sample numbers used throughout this report are identical with those used in Report of Investigations 3063; for example, No. 225 of this report is the same sample as No. 225 of Report of Investigations 3063. This is the first semiannual motor gasoline survey of the Bureau 6f Mines in which some data were obtained on antiknock values for samples collected in the survey. The Bureau of Mines is not provided with equipment for making these tests in its own laboratories, but composite samples were tested in the laboratories of the Bureau of Standards and the report on these samples is given as a supplement to this paper (pp. 11 to 14).

Jan 1, 1931

By A. J. Kraemer

This paper is the second and concluding report of the results of the Bureau of Mines' twenty-second semiannual survey of motor fuel marketed in the United States. The first paper Was published as Report of Investigations 30634 and reported data relating to gravity, vapor pressure, and distillation range of the samples. The present paper deals particularly with results of the determination of copper strip corrosion (method 530.22),5 color (method 10.11),6 sulphur content by the lamp method, 7 copper dish evaporation residue (method 530.1),8 and "gum" content as given by the steam-oven method as developed by the Bureau of Mines. 9 The price at the time the sample was taken and the tax are also stated for each sample. The sample numbers used throughout this report are identical with those used in Report of Investigations 306310; ?for example, No. 225 of this report is the same sample as No. 225 of Report of Investigations 3063.

Jan 1, 1931

By H. C. Miller

For nearly a score of years the American petroleum industry has faced the problem of maintaining its economic structure while oil -producing potentialities greatly exceeded the increasing market demand for oil and its products . However , the combination of maximum civilian demand with rising defense requirements caused an all - time peak in crudeoil production in the latter half of 1941 , with a daily production (as estimated by the Bureau of Mines ) of 4,139,000 barrels in December - an increase of 16 percent over the daily production of 3,573,000 barrels in December 1940. In the event of a long war , a continuing , steady, and adequate supply of petroleum and its products for military and required civilian needs is essential, and the efficiency of recovery of oil from natural underground reservoirs will have to be maximum. Whereas it may not be possible to increase production in some fields , the output from others may have to be drawn at a much faster rate than formerly . More than 10 years ' experience in operating oil fields under proration control has demonstrated to petroleum engineers that some of the efficiency of recovery of oil from reservoir sands and rocks is sacrificed if the oil and gas are withdrawn at too . rapid a rate . As petroleum is an irreplaceable natural resource for which suitable substitutes probably will not be available in desired quantities for many years , any producing method that jeopardizes the quantity of oil that may be recovered from underground reservoirs must be considered at this time of declared war against aggressor nations as conflicting with the best interests of national defense . At best, the efficient recovery of oil is a complex problem . It involves not only a knowledge and application of the fundamentals of fluid flow through porous mediums, but the sources of energy responsible for the movement of oil and gas through reservoir sands and porous rocks to wells must be known to determine the best practices for extracting these hydrocarbons . Reservoir energy is of two kinds - (1 ) water under hydrostatic head underlying the oil in the extraneous parts of the reservoir system and ( 2 ) natural gas under pressure as "free " gas in the reservoir or in solution in the oil . Inasmuch as the efficiency of oil recovery depends largely on the manner in which reservoir energy is used to move oil through reservoir sands and porous rocks to wells , optimum practices for withdrawing the oil cannot be determined until it has been established that the oil in the reservoirs is being forced to wells by an internal gas expansion, by a natural water drive , or by a combination of gas expansion and water drive . There is a fundamental difference in the performance characteristics of gas - expansion and water - drive reservoirs . In a strictly gas - expansion reservoir the energy available to move oil and gas through the porous formations to wells results solely from gas pressure , which is maximum when the reservoir is tapped by the first well . Pressures decline as oil and gas are withdrawn ; consequently, the energy available for moving oil and gas through the oil - bearing formations to wells decreases with production . Curtailing the oil - production rate or shutting in gas - expansion reservoirs entirely will not act to replenish energy previously used in the production of oil and gas ; in their operation , therefore , it is especially important not to waste reservoir energy - the production of oil with high gas : oil ratios will be reflected in lower ultimate recoveries of oil .

Apr 1, 1942

By James D. Brown

The Bureau of Mines has written a computer program in FORTRAN to facilitate the calculation of concentrations from X-ray intensities in electron probe microanalysis. Philibert's absorption and Castaing's secondary fluorescence corrections are used; no atomic number correction is included. Background and dead time corrections are applied to the data before calculating the relative intensities. Data from any type of electron probe microanalyzer can be used with the program.

Jan 1, 1965

By T. T. Campbell

Although secondary recovery of lead and lead-tin alloys has been common practice in the United States during recent years, there is little published in-formation concerning recovery techniques. Available information does not cover metal recovery from wet dross skimmings. This investigation by the Bureau of Mines was undertaken to develop techniques that would allow lead-tin alloys to be recovered from wet dross skimmings containing large amounts of zinc chloride. A process was developed, on a laboratory scale, for recovering lead-tin alloys from wet solder dross skimmings. Straight water leaching, either with or without a second leaching operation carried out with a Na2C03 addition for removing chloride, produced a dross that could be smelted without further treatment. Overall recoveries averaging 92 percent of the metal values in the dross were obtained in the form of lead-tin alloys, which had an average tin content of 16 percent and lead content of 84 percent. The recovered alloy contained less than 0.02 percent zinc, as determined by both chemical and spectrographic analyses.

Jan 1, 1956

By Alice M. Chieruzzi

This Country Documentation Report presents the development of economic indices for Zambia for the period from 1970 through 1981. The work done through the Bureau of' Mines, Minerals Availability Program, under Contract number J0225001. This contract calls for the development of twelve index time series describing factor input costs in the mining sector of 95 countries. The twelve index time series describe the costs of: 1) mining wages, 2) construction wages, 3) equipment and repair parts, 4) bits and related steel, 5) timber and lumber, 6) fuel, 7) powder and blasting agents, 8) tires, 9) construction materials, 10) industrial materials, 11) transportation, and 12) electrical power. These indices combined with weight factors being developed by the personnel of the Minerals Availability Field Office (MAFO) of the Bureau of Mines in Denver, Colorado, will be used to perform instantaneous updates of all costs relating to the mining industry. The indices were developed primarily for use in the Bureau's Minerals Availability Program in assessing the worldwide availability of nonfuel minerals.

Jan 1, 1983

By R. V. Higgins

As part of a study of application of the Buckley-Leverett method to an analysis of oil-reservoir performance covering a wide range of relative permeabilities and oil saturations, a method has been devised for quickly deter-mining average water saturation at breakthrough from relative permeability data. The base for the relative permeability used in the report is either the permeability to air or the effective permeability to oil at the irreducible water saturation. The permeability to air also was used because of the large backlog of air permeabilities available to reservoir engineers. The basic data were calculated by an electronic computer and are presented in a single graph from which the point of breakthrough may be obtained. In this study the water saturation at the beginning of the depletion is the connate or interstitial or irreducible water saturation. These water saturations are considered to be synonymous and to have a practical value.

Jan 1, 1960

By J. W. Paul

A study of mining methods and underground practices as they influence injury from falls of roof or coal reveals data as to the location in the mine where such injuries occur with the greatest frequency and as to some of the methods and practices which are in use for the prevention of injury. This paper, which presents statistics bearing on the frequency and place of occurrence of accidents and discusses regulations and practices which have resulted in a low-frequency rates from falls of roof and coal in a few representative mines, takes its information from mine-accident reports and from the results of studies conducted in a group of 80 mines in the bituminous coal fields of Western Pennsylvania, Ohio, and West Virginia. The statistics from this group of mines cover periods of one to four years but average 2 years and 7 months. During this time these mines produced over 110,400,000 tons of coal, equivalent to one-fifth of the annual production of all bituminous mines in the United States. The coal beds of the mines in the group studied are mostly flat, with local pitches of moderate degree. A number of mining plans are in use, each of which follows a general system of multiple entries, gross entries, and rooms. Room and pillar in panels either advancing, retreating, or half advance and half retreat, and the block system are employed. The methods of pillar extraction are by splitting, slabbing, pocket-and-stump, and open end. It is hoped that in presenting some of the details of the methods and practices at particular mines of this group which have commendable records in the prevention of injury some goad may accrue to many other bituminous mines which have similar natural conditions.

Jan 1, 1933

By G. E. McElory

"INTRODUCTION The subject of mine and tunnel ventilation has two broad aspects - (1) what atmospheric conditions to obtain in underground openings and (2) how to maintain the desired conditions efficiently. The first relates primarily to quantity requirements of ventilating systems, whereas the second relates more particularly to pressure requirements. Both, therefore, determine power requirements, which is the deciding factor in any system of mine or tunnel ventilation.Both divisions of the subject have received considerable attention from the Bureau of Mines since its inception in 1910 in the form of research, service, and correlation and dissemination of information. Numerous papers on various Phases of the subject have been published, of which a selected list, numbered and arranged in chronological order by type of publication, will be found at the end of this Paper. One of these, Technical Paper 705 (25) 2/ gives a complete bibliography of Bureau of Mines publications dealing with health and safety. As indicated by the selected list of publications accompanying this paper, the health and safety aspects have received most of the attention devoted to this work, chiefly because these have been dominant factors in Bureau policy, but partly because these aspects lend themselves to laboratory research and small-scale field studies. Although considerable attention has also been devoted to the engineering aspects of mine and tunnel ventilation, there has been, in the opinion of the author, who has been engaged on this phase almost continuously for the last 30 years, only sporadic recognition of the vital effect this phase of the work could have on improving health and safety conditions. As a matter of fact, ventilation activities have constituted but a very minor part of the total work of the Bureau of Mines, as, except for a few years in the nineteen twenties, there have been only a few short intervals when more than two or three men were engaged in field work and a similar number in laboratory research directly related to mine gases or mine air."

Mar 1, 1950