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By Stephen A. Swan

Bureau of Mines researchers have collected and evaluated rollover protective structures (ROPS) f or more than 10 yr. ROPS and falling object protective structures (FOPS) are required on specified mining machines under regulations of the Mine Health and Safety Administration (MSHA). Both ROPS and FOPS are required on mining machines used in surface coal mines and surface areas of underground coal mines (30 CFR 77.403 and 7 7.4 13a), and ROPS are required on mining machines used in metal and nonmetal mining operations (30 CFR 55, 56, and 57.9-88). This illustrated manual provides mine safety personnel, MSHA inspectors, and original-equipment manufacturers with guidelines and a check- list for inspecting ROPS being used in the field. The manual discusses specific requirements of the MSHA regulations and minimum inspection and maintenance checks for ensuring compliance with those regulations. An easily reproducible checklist is provided as an aid to the inspection of ROPS.

Jan 1, 1985

By R. A. Cattell

With the activities of the Petroleum and Natural Gas Division geared chiefly to problems directly connected with the war effort , the emphasis of the work under oil and gas development and production was to make engineering studies of selected reservoirs for the Petroleum Administration for War , to determine the extractable quantities of components in them, and to study the characteristics of these components for use in the manufacture of aviation gasoline and other products . The needs of the Petroleum Administration for War and the operators for specific data from gas - condensate fields were fulfilled , and , in addition , engineering data along lines of a forward - looking program of research on reservoir behavior were collected , which should be of great value in the postwar period . It is planned to publish many of these data as soon as conditions permit . The work of the Secondary Recovery Section had as its objectives in- . creasing the rate of production of crude petroleum and , which is more important , preventing the premature abandonment of wells in " stripper " and marginal According to the National Survey of Stripper Wells by the National Stripper Well Association in cooperation with the Interstate Oil Compact Commission , a total of 67,460 stripper wells was abandoned from January 1 , 1935 , to July 1 , 1942 , inclusive , with an estimated loss in proved reserves of approximately 216 million barrels . This survey also indicates that over 1.2 billion barrels of oil would be recovered by primary production from more than 290,000 stripper wells then in operation , and an additional 2.5 billion barrels of oil could be recovered from them by secondary production methods . The work of the Chemistry and Refining Section was oriented towards the optimum utilization of crude oils in the manufacture of aviation fuels for spark-ignition and jet - propulsion engines . The work involved intensive studies of superfractionation , hydrocarbon analysis , and the engine testing of fuels . Particular attention was given to the effect of sulfur compounds in the crude oils and in the fuels made from them . The research on thermodynamics is concerned with the experimental determination of precise and accurate values of the fundamental thermodynamic constants of pure hydrocarbons and related compounds . The data obtained in these investigations will be utilized for devising and improving chemical processes in which petroleum hydrocarbons are the raw materials . Without such data , much time and expensive material and equipment may be wasted in attempts to obtain reactions under conditions that the laws of thermodynamics rule out of consideration . Thermodynamic data are useful and required in the petroleum industry for calculations of heat balances in the design of furnaces , fractionating towers , and heat- transfer equipment . It is of utmost importance , also , to know the heat requirements of cracking and other chemical reactions so that heat may be supplied or dissipated in the proper proportions . These needs for thermodynamic data are being recognized more and more by petroleum -refining engineers . The responsibility for the production of helium for the Navy , the Army , other governmental agencies and non-Federal users is vested in the Bureau of Mines by an Act of Congress ( 50 Stat . 885 ; 50 U.S.c. 161-166 ) . The Helium Subdivision of the Petroleum and Natural Gas Division continued to meet all demands for helium .

Jun 1, 1949

By O. Q. Leone

Composite diaphragms were used in the investigation of electrowinning Ti from TiC14 in a fused LiCl-KCI-TiC'2 electrolyte. Composite diaphragms tested were of two general classes--those consisting of two or more solid materials, and those which contained, in addition, a loose material. An electrowinning cell using a flat diaphragm is described. The maximum current density for these diaphragms was 300 amp per ft2. Lower currents permitted longer operation times. The composite diaphragms gave electrode efficiencies that averaged approximately 60 percent, and the electrowon titanium was of good quality--some Brinell hardnesses were as low as 68.

Jan 1, 1972

By H. D. Baylor

This paper, describing the operations of the Louisville Cement Co. in quarrying limestone for the manufacture of quicklime, is one of a series being prepared for and published by the United States Bureau of Mines on stone quarries throughout the United States. Those papers are designed to disseminate technical information regarding the methods used. The cost tabulations represent operating only and not total costs. It is recognized that publication of total costs might in many instances cause embarrassment to individual operators as well as to the industry as a whole. On the other hand, operating costs are essential to the technical discussion and study of the methods employed. The attention of the reader is specifically called to this differentiation in order that no misunderstanding of the scope of the cost tabulations shall ensue. ACKNOWLEDGMENTS The author acknowledges the assistance of J. H. Lemmon, plant superintendent, Charles Taylor, plant engineer, and F. H. Compton, chief engineer, of the Louisville Cement Co. in the compilation and preparation of this paper.

Jan 1, 1932

By E. G. King, W. W. Weller

Low- temperature heat capacity measurements of muscovite were made in the temperature range from 50° to 298 ° K. The entropy at 298.15 ° K was evaluated as S298.15 = 69.0 ± 0.7 cal /deg mole .

Jul 1, 1960

By N. E. Hanna

An important goal in the development of coal mining explosives has been to improve their safety characteristics through suitable formulation. In the United States no systematic effort to establish factors influencing the incendivity to firedamp and to coal dust of explosives through research was made until the last decade. In consequence, American permissible explosives underwent only very slight modifications and many remained substantially the same as in the early years. As part of a long range program for increasing the safety of permissible explosives, the Bureau of Mines undertook to determine how the amounts and particle sizes of the principal constituents of these explosives affect their incendivity. It was found that an increase in the relative amount of sodium chloride and a decrease in its particle size significantly decreased the incendivity of our permissible explosives to firedamp (7-9).6 This is in agreement with findings reported by Dolan (4) for compositions of nitroglycerin and salt. One important result of the work at the Bruceton station has been the recent introduction of salt-formulated permissibles by several explosives manufacturers. This paper describes a statistically designed experiment for studying the effects of the particle size of ammonium nitrate and the type of carbonaceous materials used on the incendivity of permissible explosives. Interest in these particular effects goes back as far as the first formulations of coal mine explosives, around 1910 in the United States and even earlier in Great Britain and other countries. Although it is well established that fine

Jan 1, 1961

By David C. Oyler

Methane-drainage holes must be completely filled by grout before mining to prevent the emission of large quantities of gas during mine-through, which would constitute an explosion hazard. In November 1980, seven horizontal holes at the multipurpose borehole, a small-diameter shaft drilled as a Bureau of Mines coalbed methane-drainage installation on the property of the Federal No. 2 Mine, Monongalia County, WV, were plugged using a sodium silicate gel grout. This report de- scribes the grout mix and the use of the grout at the multipurpose borehole, and discusses the results observed upon mine-through of the holes in early 1981. Cost data for the sodium silicate grout are also presented.

Jan 1, 1984

By Paul C. Turner

The U.S. Bureau of Mines, through an Interagency Agreement with the U.S. Army Tank-Automotive Command (TACOM), has successfully developed a steel expendable pattern casting process (EPC) for the manufacture of armorplate. The new armor is lighter and more ballistically effective than conventional rolled homogeneous armor (RHA), and costs less. An applique armor spinoff from the program was field-tested during the Gulf War. The applique armor withstood direct impacts from enemy munitions without failure.

Jan 1, 2010

By Bowles Oliver

"Modification of Quarry Process.Limestone beds are formed by processes of nature, processes that have been in operation for thousands and perhaps millions of years. Therefore, their com- position and physical properties are long-established and unalterable features over which man has no control. He must take them as he fields them.It is undoubtedly true that the character of lime depends largely on the nature of the parent limestone. A high-calcium lime cannot be manufactured from a dolomite, nor can a pure lime result from the calcination of an impure raw material. However, in the process of turning limestone into lime man is not entirely helpless in his control of quality. Even though a deposit is variable in character a single lime product of uniform quality may be produced by judicious quarrying. A single grade of product may not always be desired, the producer may wish to supply the needs of a variety of users each demanding U different grade or quality of lime such a series of graded products may be produced in part at least by modifying the quarry method. Thus, by changes in quarry practice a single product or a variety of products may be made. The latter problem will be considered at a later time, and the present paper devoted to the first named question' that of producing a single grade of lime from a deposit of variable rock,It is realized of course that uniformity in the product is influenced greatly by manufacturing processes such as calcining' hydrating' grinding or storage, but the present discussion is confined to the influence of raw materials only. In considering the various devices that may be employed it is realized that much remains to be learned, and it is hoped that many operators will contribute to the discussion as they have already done in connection with previous papers of this series."

May 1, 1923

By R. V. Ramani, A. S. C. Owili-eger

Mathematical modeling is a scientific exercise with the objective of developing simplified mathematical statements that relate to one another the same way as the processes that are being modeled. The utility value of the model is dependent on the ability of the model to closely approximate prototype behavior. Development of a perfect model, therefore, is an unrealistic objective because of the simpli¬fying assumptions made in building it. However, for a model to be acceptable for application, its operating characteristics or data generated from it should, within reasonable accuracy, duplicate proto¬performance. The validity and accuracy of a model depends on the mathematical constraints presupposed in model formulation. The final model must be tested for mathematical validity and for closeness of representation of the prototype. Mathematical validity, does not, however, imply that the model is accurate and correct but is prerequisite. Model testing and verification for the steady state model are given in Owili-Eger et al (1973). The unsteady state model has been tested for mathematical validity and found to be correct but has not yet been applied to a field condition for lack of data. However, in the application discussed below, the unsteady state model results are compared with pressure curves reported in literature and also with results from the steady state model. Coal seam characteristics and gas reservoir pressure used in this application are extracted from Kissell (1972). These characteristics are for the Pittsburgh seam, Federal No. 2 Mine, Fairview, West Virginia.

Jan 1, 1974

By R. C. Buehl, J. P. Riott, M. B. Royer

Sponge iron is the metallic product resulting from the reduction (removal of combined oxygen) of iron ore or other iron oxides at a temperature below the fusion point of iron. It has been used for many years in the production of certain grades of high-quality steel, such as tool and cutlery steels. The sponge iron available commercially in limited quantities for such use was produced from high-grade ores that were almost free from the contaminating elements that are generally considered detrimental to the production of certain grades of carbon tool steel. Interest in sponge iron as a scrap substitute was revived when World War II began, when the serious shortage of scrap metals for use in the production of armament caused great concern as to whether steel production could be maintained at the rate necessary for vigorous prosecution of the war effort. Also, because of the severe shortage, steel manufacturers…

Jun 1, 1947

By John D. Corrick

The environmental and nutritional characteristics necessary for maximum copper extraction from a low-grade ore by Ferrobacillus ferrooxidans have been explored as have many of the limiting parameters. Criteria considered were oxygen consumption, copper extracted, soluble copper concentration, temperature, pH, particle size, nutrients, and other inorganic salt concentrations. A set of environmental and nutritional conditions were developed for E. ferrooxidans Which supported cell reproduction and maximum microbial oxidation of a low-grade copper sulfide ore. Percolator tests conducted under these optimum conditions resulted in an 18 percent increase in the quantity of copper microbially extracted over that extracted under conditions considered to be standard. Manometric tests determined those extremes of environmental conditions and nutritional factors Which were detrimental to the extraction of copper by E. ferrooxidans.

Jan 1, 1965

By John J. Sammarco

Computer-related accidents have caused injuries and fatalities in mining as well as other industries. Normal accident theory (NAT) explains that some accidents are inevitable because of system complexity. NAT is a classic argument in organizational sociology although it has been criticized as having imprecise definitions and lacking criteria for quantifying complexity. These limitations are addressed by a unique approach that recasts this organizational theory into an engineering-based methodology to quantify NAT complexities of computer-based systems. In this approach complexity is categorized as external or internal. External complexity is defined by the external behavior of a system, and is quantified by these dependent variables: system predictability, observability, and usability. Dependent variable data contain the perceptions of 32 subjects running simulations of a system. The system?s internal complexity is characterized by modeling system-level requirements with the software cost reduction (SCR) formal method. Model attributes are quantified using 15 graph-theoretical metrics?the independent variables. Five of 15 metrics are correlated with the dependent variables as evidenced by structure correlations exceeding 0.25, with standard errors <0.10 and a 95% confidence interval. The results also show that the system predictability, observability, and usability decreased as NAT complexities increased. This research takes a step forward in operationalizing NAT for computerized systems. The research benefits mining and other industries as well.

Jan 1, 2005

By James R. Welty

Heat content values were experimentally determined for yttrium metal between temperatures of 400° and 1,300° K and for iron pentacarbonyl between 301° and 380° K. The drop technique was used; that is, a sample of material sealed in a protective capsule was heated to 3 desired temperature in a furnace and then dropped into an ice calorimeter. A revised technique for determining heat content values from calorimetric data is described. Heat content and corresponding entropy-increment data above a reference temperature of 298.15° K are presented in tabular form. Equations for heat content and heat capacity as functions of temperature were derived for each substance. These equations are [Y (c): HT-H298.15 = 1.2041T 1 3.393 x 10-3T2- 0.4176 x 10&apos; T"1 + 739.9 cal/mole Cp = 1.2041 + 6.786 x 10-3T + 0.4176 x 106-T-2 cal/deg mole Fe (CO) E, (1) : HT - H298.15 = 55.636T - 16,588 cal/mole Cp = 55.636 cal/deg mole]

Jan 1, 1963

Develop a method for recovering phosphate from a wide variety of complex western phosphate materials, including low-grade ores, tailings, and unused fines. Approach A flotation technique is used for this broad type of extraction. The method includes depression of phosphate minerals and anionic flotation of carbonate minerals, followed by cationic flotation of silicate minerals. How It Works A slurry is prepared for flotation by sizing to remove a low-grade, high-impurity slime fraction. Depending on the material, further sizing and/or grinding steps may be used to produce a size concentrate or to remove gangue. The flotation feed is conditioned with H2SiF6 and a fatty acid emulsion. The H2SiF6 is absorbed chemically to the phosphate mineral surface, making it strongly attracted to water and preventing adsorption of the fatty acid. Under these conditions, the fatty acid is a selective collector for carbonate minerals, which are removed as a froth product. Next, the silicates are floated with an amine reagent added directly to the slurry without additional pulp preparation.

Jan 1, 1982

By C. M. Flynn

The Bureau of Mines prepared and investigated xanthated sawdust adsorbents to determine their effectiveness in removing heavy metal ions from dilute aqueous solutions, mine-drainage waters, and brines. Stripping of the metal values from the metal-laden adsorbent was also investigated. The treated sawdusts had an adsorption capacity of 0.3 to 0.4 meg/g dry adsorbent for Mn, Co, Ni, Cu, Ag, Zn, Cd, Hg, or Pb from feed solutions with pH 5 to 6. The feed solutions tested included mine-drainage waters and geothermal brine. Effluent metal concentrations as low as 0.05 to 0.1 mg/l were obtained at effluent pH values of 6 to 9. The order of affinity of metals for the sawdust adsorbent is Na«Ca~Mg~Mn<Zn<Ni<Cd<Pb~Cu. The presence of Ca, Mg, or Na in concentrations as high as 2 g/l does not seriously impair the heavy-metal adsorption. Metals were desorbed from the metal-laden adsorbent by elution with dilute mineral acids, sodium cyanide, or salts of ethylenediaminetetra-acetic acid.

Jan 1, 1979

By Daryl E. Radcliffe

The Bureau of Mines, as part of an agreement with the Bear Coal Co., Somerset, Col o., evaluated the response of a coal mine roof to time lapse. Time lapse, the interval between exposure and support of the roof, was studied using both instrumentation and statistics. Instrumentation studies were designed to equate displacement and rates of displacement with areas of roof left unsupported from 15 minutes to more than 4 days. A statistical study was completed to compare roof fall occurrence with time lapse intervals encountered during normal room-and-pillar mining. Results from this investigation show time lapse, in the Bear mine, to he insignificant with respect to roof stability after installation of permanent support.

Jan 1, 1980

By Liming Yuan

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Jan 1, 2009

By E. L. Litchfield

Spark ignition of combustible-gas mixtures is a relatively old subject of investigation and has been treated both experimentally and analytically by many people. Elements of static and current electricity are almost always present in mining and industrial operations, and the spark can be an extremely efficient source of ignition. Thus the practical interest of such problems as the "intrinsic safety" of electrical apparatus is obvious. Ignition and quenching phenomena are the primary laboratory representatives of combustion phenomena that are dynamically nonsteady, and such nonsteady phenomena playa considerable part both in industrial processes and in safety matters, although they are of less immediate practical interest. Considerable effort has been expended by the Federal Bureau of Mines in investigations of spark ignition.5 6 7 8/ Primarily, this work has established the significance of several of the parameters involved. Although the

Jan 1, 1959

By C. H. Gorski

Evaluation of raw materials for mineral wool is one phase of the Bureau of Mines broad program for the more effective utilization: of our mineral resources. The experimental work and test-evaluation results on several raw materials as useful components for the production of mineral wool are presented in this report. Samples from all sections of the United States, including copper slag from Tacoma, Wash., pebble phosphate slime from Florida, and granites from Massachusetts and Minnesota, have been blown into mineral wool successfully in the laboratory tests. Maximum conservation of the Nation&apos;s mineral and manpower resources requires maximum utility of those resources. Al though the domestic reserves of oil, gas, and coal are tremendous, judicious use of these fuels through the use of proper insulation will insure the highest thermal efficiency. The effectiveness of mineral wool as a heat-insulating material has assumed an increasingly important role in the national economy, and it has become a fuel saver in countless applications. The most immediate concern to many is the use of mineral wool in the home, which promotes uniform temperature and minimizes drafts by reducing heat transfer through the walls, ceiling, and floors. There are, however, many industrial and commercial uses that require large volumes of mineral wool each year.

Jan 1, 1951