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By James Westfield

Bureau of Mines activities for safety and health in the mineral industries were reorganized during the fiscal year to provide direct supervision by the Assistant Director -Health and Safety. On December 19, 1954, the field offices conducting these activities were designated as district health and safety offices reporting to the Assistant Director. The functions of determining the causes of accidents and injuries in the mineral industries and recommending measures to eliminate them were continued, with satisfactory results in improved safety records. The inspection of coal mines and enforcement of the Federal Coal Mine Safety Act of 1952 were conducted as directed by the Congress, and safety conditions in the mines were notably improved. One coal-mine explosion classed as a major disaster occurred during the year. The causes of that explosion and means for preventing a recurrence were still under investigation because of the extreme difficulty in recovering several portions of the mine. Basic research on the nature of certain hazards and ways of eliminating them is continued. Training of individual workmen and supervisors in this knowledge is a major part of the work.

Jan 1, 1956

By J. Moskowitz

Construction of the new JFK International Airport Light Rail System (LRS) began in 1998 with a pre-construction load test program. This $1.2 billion design-build project consists of approximately 13 kilometers of elevated twin rail. The elevated rail system is supported on nearly 500 piers requiring deep foundations. The presence of underlying compressible and liquefiable soils as well as space constraints precluded the use of large spread footings. In the 1980's the Port Authority undertook extensive testing to evaluate various piles and drilled shafts types. The LRS piling sub-contractor and the Geotechnical Engineer conducted additional tests for this project to identify the most cost effective deep foundation type. Candidate piles types included: Monotube®, Tapertube®, and closed ended pipe piles. The tapered pile types were found to be the most cost effective and the project utilized both the Monotube® and Tapertube® piles. This paper presents the results of the load test program and the issues related to pile driving induced vibrations and ground movement.

Jan 1, 2000

By Scott Ellenbecker

Soon New York City will have a new train station. A tunnel project is under construction to extend Line 7 to a new station that is located near the Jacob K. Javits Con-vention Center. This is also part of the Hudson Yards redevelopment project that is intended to aid redevelop-ment of the west side of Midtown Manhattan around the Long Island Railroad?s Caemmerer Railyard. The station, or ?cavern? as it?s called by those excavating it, will be the portal for that growth. In the city, public transportation means high-rise residential proper-ties will have better access to the business district, and those outside the area will have greater access to event facilities ? two factors that are critical for development investment.

Jan 3, 2010

China’s vibrant economic growth is built on coal, the source of two thirds of the country’s electricity. Over 95 percent of China’s coal is mined underground with the average mining depth at 410 m and in-creasing at 10 m per year; today, the deepest Chinese coal mines have exceeded 1,000 m. With increasing mining depths, there are greater challenges including increased methane emissions and spontaneous combustion. According to the government, nearly half of China’s coal mines are classified as gassy (with specific gas content at least 10 m3/mt). Coalbed methane (CBM) is a clean energy source. However, only a small percentage of the methane is captured, and the rest is vented directly to the atmosphere. This paper describes China’s CBM resource, its production and utilization.

Jan 1, 2006

By R. J. Watson, A. H. Juch

About half a million sucker-rod pumps are installed in oil wells in the U. S. alone. In Venezuela, too, the system is widely used; some 5,000, or 90 percent, of Cia. Shell de Venezuela's wells produce a total of 400,000 BOPD by this method. Most of the crude pumped is viscous, gassy and contains relatively small amounts of free water. API gravities vary from 90 to 16O; dead oil viscosities vary from 10 to 10,000 cp at the pump; and GOR's range from 100 to 2,000 cu ft/bbl. Pumps are set at depths ranging from a few hundred to 6,000 ft; the average setting depth is about 2,500 ft. From the literature, it appears that although recent years have seen significant progress toward understanding the rod pumping system as a whole, relatively little attention has been paid to those key items, the sucker-rod pump and the subsurface gas separator or gas anchor. Perhaps because of proration in the U. S., pump manufacturers have seemingly concerned themselves more with the durability of their product, achieved mainly through robust design and metallurgical know-how, than with its working efficiency. In 1963, CSV commenced a major rehabilitation and expansion of its heavy oil fields along the Bolivar Coast. The advent of the more efficient gravel-packed completion and of large-scale thermal recovery (mainly steam soak) operations resulted in well potentials *Now with B. I. P. M., The Hague, The Netherlands. greater than pump capacities. Hence, an urgent need arose to improve over-all pump efficiencies and to attack those special problems related to the production of both the extremely viscous and the hot, steam-laden crudes that formed an increasing proportion of the total stream. There followed a detailed investigation and testing program, carried out in close cooperation with a major pump manufacturer. This culminated in the introduction to the oil industry of a new line of sucker-rod pumps. Early Investigations and Experiments Field Tests Extensive field tests were carried out in three primary Bolivar Coast wells with an in-situ dead oil viscosity ranging from 400 to 6,000 cp. In these installations provision was made to (1) monitor bottom-hole pressures below, in and above the pump by means of pressure transducers, and record casing- and tubing-head pressures continuously; (2) measure accurately the annulus gas, as well as measure the tubing gas and liquid production from the well; (3) take special PVT samples of the well fluid; (4) measure power consumption of the prime mover; and (5) measure the rod loads at the polished rod. A typical test installation is illustrated in Fig. 1. It was established from the pressure transducers that with viscous oils, there is considerable flow resistance across the pump and gas anchor assembly. Pressure surges were observed over each pump cycle,

Jan 1, 1970

By Sara J. Davenport

The human race has been exposed to copper for thousands of years, as copper and gold were the metals first used by man (1). if According to Ramazzini (2), "of all the metals that man's ingenuity has contrived to dig out of the bowels of the earth, iron and copper are the most useful, far more so than silver and gold." Workings of copper in the oldest known copper mine associated with the smelting of this metal have been traced back to 4300 B. C. Facts revealed by archeological research in India, Austria, Hungary, France, Italy, and Spain indicate that the use of copper probably began about 5000 B.C. (3), and that about 4000 B.C. a copper age came intermediate between the stone and bronze ages (4). Copper ores are rather widely distributed and are found in nearly every country. Many of the copper minas of Europe have been worked since before the Roman Empire. The must important mines in Europe occur in the district around Huelva, extending into Spain and Portugal. The German deposits are located mainly about Mansfeld (Rhenish Prussia); they have been worked continuously for 1,000 years. Some of the mines in Africa have been worked by the natives for centuries, and China has produced copper from shallow pits for thousands of years. India also has many ancient mines worked in the early centuries (2).

Jan 1, 1953

By A. K. Majumder

The multi-gravity separator (MGS) is a novel piece of equipment for the separation of fine and ultra-fine minerals. However, the published literature does not demonstrate its use in the separation of coal fines. Therefore, an attempt was made to study the effects of different process variables on the performance of an MGS for the beneficiation of coal fines. The results obtained from this study revealed that among the parameters studied, drum rotation and feed solids concentration play dominating roles in controlling the yield and ash content of the clean coal. Mathematical modeling equations that correlate the variables studied and the yield and ash contents of the clean coal were developed to predict the performance of an MGS under different operating and design conditions. The entire exercise revealed that the MGS could produce a clean coal with an ash content of 14.67% and a yield of 71.23% from a feed coal having an ash content of 24.61%.

Jan 1, 2007

By N. B. Pundari

Proper selection of large walking draglines, based on sound engineering principles and field experience, has not kept pace with the large capital expenditures needed to buy these stripping machines. The use of large walking draglines for stripping overburden in US surface coal mines grows steadily, but equipment selection continues to pose problems. An improper size, model, make, or spoil reach selected for a particular stripping application results in additional, unnecessary coal production costs. Large walking draglines are being used to dig deeper tar sands at the Syncrude operations near Fort McMurray in Northern Alberta, Canada. This application is compared with typical deep digging operations and dragline use prevalent at typical US strip mines.

Jan 4, 1981

By Richard E. Thill

The Bureau of Mines' Oil Shale Data Bank (OSDB) was created in 1976 to serve as a centralized source for the storage, retrieval, and dissemination of technical literature, patents, and information on research projects in oil shale. Thousands of bibliographic references, patents, and research projects relating to the mining of oil shale have been identified, abstracted, and indexed according to selected keyword topics. The resulting data bank listings are contained in three sections, each with a separate keyword breakdown for use in rapidly identifying references pertaining to a specific subject. All references cited in the OSDB were published prior to an established cut-off date of May 1, 1981, when a redirection of Bureau of Mines programs resulted in the loss of project funds and the subsequent phasing-out of data bank operations. ACKNOWLEDGMENTS The oil shale data bank listings are the result of a team effort of the project staff. The contributions of Jimaleen Jansma for keypunching, information acquisition, and data entry, and John Brandenburg and Sandra rake for keywording and information acquisition are gratefully acknowledged. Appreciation is expressed to the staff members of the Smithsonian Science Information Exchange, Washington D.C. for their cooperation in supplying data on recent research projects in oil shale for inclusion in the OSDR listings. Appreciation is extended also to the staff of the Gallegos Research Group for assisting with computer services to obtain the final printouts and transfer of files onto magnetic tape.

Jan 1, 1982

By John C. Machisak

INJURY and employment figures for nonmetal mines and mills in 1959 are presented in this publication. Data for nonmetal mines are presented separately from those for nonmetal mills. The Bureau of Mines is authorized to send questionnaires to the nonmetal mining industry each year requesting their voluntary submission of injury experience and employment data. The voluntary response to these requests has contributed greatly toward the promotion of safety in the industry, and every effort has been made to make the information as complete as possible.

Jan 1, 1963

By Patrick D. Plumb

The Juneau Office of the U.S. Bureau of Mines has undertaken a study of the environmental permitting process for major mines in Alaska to identify the effects ecosystem management has had or could have on the permitting process. To date, ecosystem management affects major mine permitting in Alaska primarily through the NEPA environmental assessment process. In Alaska, only the Forest Service has instituted ecosystem management in an overt and organized manner, while other agencies are doing so less directly. In recent Bureau of Mines publications, the mine permitting process has been described using case studies of several recently permitted mines in Alaska. The insights into the permitting process and the conclusions of these reports are reviewed and summarized. Several ecosystem management issues were identified in the case studies, including the need for: effective communication between agencies; standardization and coordination of NEPA environmental impact assessment and environmental monitoring programs among agencies, and assessment and selection of alternatives based on risks to ecosystems regardless of jurisdictional boundaries or environmental media-specific regulations. Ecosystem management could be used as a way to systematize, organize, standardize, and coordinate permitting and monitoring requirements and management perspectives among government agencies and project proponents.

Jan 1, 1993

By Víctor De la Cruz

Dado que la mina Rosaura (Lima) se dedica a la explotación de minerales polimetálicos como el zinc, plomo, cobre y plata, la caracterización geomecánica de su estructura, morfología y reservas demostró una tendencia hacia los métodos masivos -en tanto presenta ventajas técnico-económicas comparativas frente a otros posibles métodos como el corte y relleno y conjunto de cuadros. Por ello, el presente texto describe el método de “Hundimiento por Subniveles” (Sub Level Caving – SLC), como el más indicado. El SLC se basa en la utilización del flujo gravitacional del mineral fragmentado a través de la perforación, voladura, y el hundimiento de la roca estéril principalmente de la caja techo. El diseño del elipsoide de extracción determinará la ubicación de los Sub niveles y Drawpoints, los cuales serán críticos para hacer rentable el minado, de forma que los beneficios actuales del método indican niveles altos de Seguridad, recuperación alta de mineral, bajos costos y mejora constante de la productividad.

Sep 9, 2007

By Xu Youzai

Static loading teets of five nodular piles and four non-nodular piles were performed in Tianjin soft clayey soil in which measurements of axial force and movements were made. Distribution of shaft resistance and load-movment curves for pile head and pile toe are presented in this paper. The applicability of nodular piles to soft soil and their effectiveness are also discussed. Based on the comparison, it is concluded that nodular piles have an advantage over non-nodular piles mainly in contri­bution to shaft resistance. Dynamic testing was also conducted through R. P. T. for evaluating the service load of tested piles.

Jan 1, 1991

Two miners were fatally injured when a pillar bump occurred during retreat mining in a southern West Virginia coal mine. The mine was operating in the Eagle seam with overmining in the No. 2 Gas and Powellton seams. A coal bump is defined as a sudden and violent failure of coal caused by the release of stored strain energy in the pillar. While significant strides have been made by academia, industry, and regulatory agencies to better understand bump conditions and mitigation techniques, coal bumps represent a long standing, highly site-specific engineering problem in which the exact failure mechanism(s) is not clearly understood.

Jan 7, 2020

By Richard R. Brochu

At the International Society ofExplosives Engineers Annual Conference held in Nashville, Tennessee in February 1995, a Seismograph Standards Committee was established. The purpose of this wmmittee was to develop objective performance specifications for vibration measurement instrumentation and field use practices. It was also understood that due to geology, temperature, and moisture in the soils, it is not possible to design and build an instrument to give ‘results which are absolutely comparable for ground vibration. It was, however, considered essential to standardize instrumentation by which vibration can be measured under closely defined conditions so that results obtained by users of seismographs are always the same ,&thin stated tolerances.

Jan 1, 1998

By Godofredo Murillo P

"El objetivo del trabajo es señalar la aplicación del método de sostenimiento a través de los ""pernos de madera"" en las minas de Colquijirca, Cerro de Pasco. La ejecución de este método fue a raíz de la lectura de una de las publicaciones que edita el American Institute of Mining and Metallurgical Engineer, titulada Mining Engineering. Posteriormente se elaboraron varias pruebas, encontrándose en está ultima, un rajo de 18 metros por 6 metros, levantado un promedio de 2 metros y medio, y en el que se colocan los pernos de modo perpendicular a la inclinación del manto, llenando todo el rajo y acomodándose en el rombo. Asimismo se demostró que la fabricación de ""pernos de madera"", cuñas y cabezales en un tiempo de cuatro horas, es mucho mayor que las colocadas regularmente con un ayudante. Por último, se resalta que la eficacia de este método responde al factor de que la roca floja es sementada dentro de un bloque sólido, que es suspendido por los lazos del cable de acero en los huecos perforados en un zona sólida, dando mayor seguridad a los trabajos de sostenimiento en los rajos, asi como facilidad en sus instalaciones."

Jul 20, 1955

By Ronald M. Lewis

Quadratic functions, Q(hkl), are given to six places in increments of 0.01° for 2? from 00 to 90° for FeKa and from 25° to 180° for FeKa1. The wavelengths used for Fe in the computation are those agreed upon by the Editorial Commission of the International Tables for X-ray Crystallography (1950): FeKa1 1.93597 A.; Feka2 1.93991 A. INTRODUCTION At the Federal Bureau of Mines laboratory, Norris, Tenn. X-ray diffraction crystallography using tubes with iron targets revealed a need for a handy reference for the quadratic functions of iron radiation. The tables presented here were prepared to satisfy that need. The quadratic form Q(hkl) may be expressed in terms of the Bragg diffraction angle 2? and of the wavelength ? as

Jan 1, 1961

By D. E. Larson

The U.S. Bureau of Mines investigated Fe-base alloys containing 8 pet Crwith Ni, AI, and Si additions as substitutes for standard AISI Type 304 stainless steel (SS) in high-temperature oxidizing applications. The objective of this study was to reduce the amount of Cr required to make an austenitic stainless steel while retaining satisfactory workability, mechanical properties, and oxidation resistance. Alloys prepared in this investigation had a composition of Fe-8Cr-lMn-0.07C with varying amounts of Ni, AI, and Si. A minimum of 10 pet Ni was required to achieve an austenitic composition. The microstructures of the austenitic alloys were very susceptible to room-temperature, deformation-induced martensitic transformations. When the alloys were cold worked or stressed, the materials had far greater tensile strengths than Type 304 SS at room temperature. At higher temperatures, tensile strengths and workability of several of the alloys were comparable to that of Type 304 SS. Although martensitic transformation caused the room-temperature properties of the experimental alloys to be quite different than those of Type 304 SS, the superior oxidation resistance and similar hot workability of several alloys encourage their use as replacements for Type 304 SS.

Jan 1, 1989

By Vance G. Leak

A technique for recovering copper and steel from metallic scrap has been developed by the Bureau of Mines based on preferential melting in molten salt baths at 1,150° to 1,250° C, The molten salt, preferably barium chloride or calcium chloride, both minimizes oxidation of the metals and promotes heat transfer. Cleanest separations (0.01 percent copper remaining in iron) have been achieved by pretreatment (dipping or spraying) with sodium sulphate or sodium silicate, which alters and coats the surface of the iron to inhibit the alloying or brazing with copper. An economic evaluation of the process was carried out on six combinations of sweating media and inhibiting reagents. On the basis of the postulated model, a cost of about $0.20 per pound of copper recovered has been determined for the sweating treatment operation.

Jan 1, 1973

By Anderson Carvalho Nogueira

Este artigo descreve a utilização da proteção cerâmica do composto SiO2(62-68)-MgO+CaO(29-39) na região frontal das máquinas que injetam massa refratária para interromper corridas de ferro gusa e escória em estado líquido nos altos fornos. O novo modelo de proteção (protótipo) apresentou uma economia de aproximadamente R$ 32 mil reais comparado com o composto anteriormente utilizado CaO-Al2O3-SiO2. Apresentou também menor toxidade, já que possui em sua morfologia menor quantidade de fibras. Estas fibras quando inaladas provocam danos aos tecidos internos dos pulmões sendo prejudicial à saúde. Houve manutenção dos índices de produção, pois em todas as amostras da nova proteção cerâmica testada, a parte frontal foi preservada possibilitando a injeção de massa refratária na quantidade e pressão necessárias para reconstituição do comprimento do furo que retira o ferro e escória do interior do alto forno, possibilitando um volume interno maior para se produzir mais. Os modelos de proteção usados nos testes foram da empresa Morganite. A verificação da morfologia e posterior caracterização do material foram executadas por Microscopia Eletrônica de Varredura e Difração de Raios-X.

Oct 30, 2017