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By J. Tomlinson

Shuttle car trailing cable splices were tested for resistance to failure upon being subjected to repeated bending, abrasion, and tensile shocks using a new testing method that closely simulates shuttle car induced stress. The results show that under normal stresses, splices can be made to withstand the equivalent of three months of operational use. Restoring the tensile strength to the conductors is found to be as critical as restoring flexibility. Splices in which the conductors are of slightly unequal length did not present as serious a workmanship problem as previously thought since test results show that the conductors tend to equalize when longer cables, in contrast to short cables employed in previous testing methods, were used. Dynamic recordings of cable tensile stresses are presented for a shuttle car and the new simulated testing method. Two simple but effective methods for removing insulation using a knife and a pair of pliers are described. None of the designs tested for a sacrificial splice covering were satisfactory.

Jan 1, 1979

By A. G. Smelley

As part of research conducted in its mission to effect pollution abatement, the Bureau of Mines, U. S. Department of the Interior, is developing a dewatering technique that allows for disposal of phosphatic clay wastes, for reuse of water now lost with clays, and for reclamation of mined land. The technique utilizes a high-molecular-weightnonionic polyethylene oxide polymer (PEO) that has the ability to flocculate and dewater phosphatic clay wastes. A synergistic flocculation study was made to determine whether a portion of PEO could be replaced by other reagents. Several groups of reagents were tested: (1) those that increased the zeta potential of the phosphatic clay wastes; (2) those capable of hydrogen bonding; and (3) those which flocculated the phosphatic clay waste. Reduction in PEO consumption occurred only with addition of those reagents able to flocculate the slime. The use of natural guar gums resulted in a lower PEO requirement and also yielded a dewatered product of higher solids content, 43 to 45 percent, versus 33 to 35 percent obtained with PEO alone.

Jan 1, 1980

By William G. Pariseau

Elastic-plastic finite-element simulation of cut-and-fill stoping in deep, narrow veins shows substantial quantitative agreement with field measurements of stope closure and fill pressure made at two mines in the Coeur d'Alene mining district of northern Idaho. The simulation procedure, validated by field data, was used in an analytical study of vein-wall closure and sill-pillar stress as influenced by fill modulus, rock modulus, and premining stress. Ratios of closure and pillar stress in the filled stopes to closure and pillar stress in the unfilled stopes are used as prediction indices for fill performance. In general, the support capability of fill increases dramatically as the ratio of fill modulus to rock modulus approaches 1. A significant reduction in closure .from the open stope--up to 75 percent--occurs with a relatively low-quality 10-ksi-modulus fill (rock modulus of 1,000 ksi). However, a higher quality fill is needed to achieve a substantial reduction in pillar stress from that of the open stope. A 100-ksi-modulus fill reduces pillar stress in both the 36-foot and l6-foot pillars (vein width is 10 feet) by about 50 percent relative to the open stope.

Jan 1, 1976

By Charles G. Patmon

This paper describing the methods of dredging and treatment of gold-bearing gravels at the Lancha Plana Gold Dredging Co.'s dredge is one of a series of similar papers being prepared by the Bureau of Mines on mining practices, methods, and costs in the various mining districts of the United States. The dredge is located near the Mokelumne River, 12 miles west of San Adreas, Calif.; it is accessible by an improved dirt road from Jackson, which is about 20 miles distant.

Jan 1, 1932

By J. P. Hansen

In order to help assure an adequate domestic supply of minerals essential to the Nation's economy and and security by developing more efficient minerals extraction technologies, the Bureau of Mines Tuscaloosa Research Center examined the application of autogenous microgrinding to calcium carbonate minerals. Treatment of minus 8-mesh Alabama marble resulted in a product 80 pct minus 5 micrometers (µm) at a power consumption of 70 to 80 kwhr/ton, This study shows that coarse particles of calcium carbonate minerals are effective as the grinding media for the autogenous attrition grinding of these minerals. The minus 8- plus 30-mesh fraction is an effective grinding medium (sand) for particles smaller than 30 mesh. A 40-pct-solids slurry and a sand: marble ratio of 2.5 appeared to be near optimum. For residence times above 13 minutes, products were greater than 80 pet minus 5 µm and greater than 54 pct minus 2 µm. Power consumption was uniformly low, ranging from 50 to 100 kwhr/ton of product depending upon the feed rate. One marble sample from Georgia was shown to be the most persistent grinding medium, with losses of less than half those of the other materials tested.

Jan 1, 1980

By George T. Motock

The author prepared the following report as the result of a trip to Germany in the summer of 1945 for the Technical Industrial Intelligence Commitee Subcommittee on Metals and Minerals. The purpose of this committee, which functions under the Joint Intelligence Committee of the Joint Chiefs of Staff of the United States Armed Forces and of which the Bureau of Mines

Jan 1, 1946

By Albert A. Munsch

The Munsch National First-Aid Instructors Association had its inception during the teaching of a Federal Bureau of Mines first-aid instructors' class at McPherson, Kans., under a cooperative plan of first-aid training. Upon completion of- the course on July 1, 1938 members of the class organized the charter chapter of the association under the name of McPherson (Kans.) District Charter Chapter No. 1. On July 1, 1941, 3 years after the founding of the association, there were 15 chapters in the national council -7 in Kansas, 3 in Oklahoma, 2 in Texas, 2 in New Mexico, and 1 in Arkansas. Although the pioneer work of the association was done in the petroleum industry, the plan will be of even greater benefit to a district in which there are various types of plants, mince, and operations of the mineral and allied industries. ACKNOWLEDGMENTS The writer appreciates the cooperation and assistance of the following persons: S. P. Redfearn, safety engineer, Globe Oil & Refining Co. and affiliated companies, Wichita, Kans., and H. (Chief) Moore supervisor of safety meetings, Shell Oil Co., Inc., McPherson, Kans., for their untiring efforts and enthusiasm in organizing an- attending the first class, organizing three other classes, and helping to plan the work of the association

Jan 1, 1942

A spectrographic procedure applicable to the semiquantitative determination of 29 elements in tungsten is presented. The method is designed to give estimates of impurity concentrations up to 500 p.p.m. Limits of detectability range from 0.3 p.p.m. for the more sensitive elements to 100 p.p.m. for the less sensitive ones. Tungsten metal samples varying in particle size from minus 300-to 30-mesh are excited in the presence of 5 percent germanium with a direct current arc. Germanium acts to stabilize the arc, minimizes the volatilization of tungsten, and serves as an efficient carrier to sweep impurities from the tungsten into the excitation zone. Curves are presented that show the volatilization behavior of germanium, tungsten, and impurities in tungsten at different concentration levels. Data obtained were used as guides in establishing the method of analysis. In the absence of established reliable analytical procedures for determining many impurities in tungsten in the parts per million concentration range, the spectrographic method described here should prove to be helpful in evaluating high-purity tungsten.

Jan 1, 1961

By R. G. Knickerbocker, A. L. Fox, J. Koster, P. R. Perry

"During the past several years, alunite from the Marysvale (Utah) region has been the subject of investigation by the Electrometallurgical Section of the Bureau of Mines. The nature and occurrence of this mineral, with considerable data on the Utah deposits, together with a number of results of preliminary experiments, have been given in a previous report. 6/ The geology of the Marysvale region has been reviewed recently. 7/The present paper reports the results obtained by a method involving the sintering of alunite with boric acid and subsequent treatment of the sinter to produce alumina and potassium sulphate.The preliminary work just mentioned had given indications of the separation of sulphate salts high in potassium from fusions of alunite with borax glass.During the course of further work along those lines, fusions of boric acid and alunite were tried. No separation of salts was obtained, but it was observed that rather complete removal of so3 from the alunite occurred and that the sinter could be leached with water to give a solution contain¬ing most of the potash and a residue containing most of the alumina. The reaction that takes place can probably be written 8/:"

Mar 1, 1939

By Raja V. Ramani, Robert L. Frantz

"The House/Senate Joint Conference Committee has instructed the Bureau of Mines to have the Advisory Committee on Mining and Mineral Resources Research review on an annual and simultaneous basis each generic mineral technology research center (GMTC). In order to accomplish that review promptly and uniformly, committee members have revised and approved an in-depth questionnaire. That document formed the basis of their review. The information provided by that questionnaire was an important factor in their recommendations concerning the future direction of the program; a presentation was made at the last National Plan Update.The comprehensive nature of the questionnaire and the scope of the information contained therein make it an excellent retrospective of the Center. Having a clear vision of where the Center has been and knowing where it is now will help guide it into the future. It is felt that such a detailed view of the Center's facilities and research program will be of value to Center personnel and Advisory Committee members.Each aspect of the questionnaire has been examined, answered in detail, and documented throughly. With the completed questionnaire as a guide, this volume examines the research program, Center personnel presently active on GMTC projects, number of graduate degrees granted with GMTC support, GMTC publications, degree of individual interaction, technology transfer, the reference center, GMTC equipment and facilities, and any envisioned plans for future research. It is hoped that this volume will serve as a review of the years 1984-1988, the first four years of the Center's operation."

Aug 31, 1989

By Eric R. Bauer

The magnitude and rate of advance of an inmine coal squeeze was deter-mined by measuring roof-to-floor convergence on a regular basis. A dial-gage tube extensometer was used to collect data. Using these measurements) Bureau of Mines employees drew contour maps and graphs to show the direction and rate of squeezing. Information on the rate of squeeze advance was used to determine whether steps should be taken to prevent roof and/or floor movement from closing an entire section of the mine and if alteration of mining plans was necessary to prevent further squeeze development. Data analysis revealed that the squeeze was decelerating; thus there was no need to strengthen support in the areas of the mine that were studied. Mining plans were altered, however, as a result of the findings of this investigation.

Jan 1, 1981

By Maria I. De Rosa

The U. S. Bureau of Mines performed experiments to determine if the primary gas toxicities evolved during the early (~300° C) and later (~400° C) combustion stages of chlorinated polyester-reinforced mine ventilation ducts could be predicted by a smoke particle characteristic, for the development of a test parameter. The experiments were conducted in an approximately 20-L furnace, at 14-min durations at set furnace temperatures of 2500 and 1,000° C, with an airflow through the furnace of 10 L/min. The variables studied, as a function of time, were the hydrogen chloride (HCI), carbon monoxide (CO), carbon dioxide (C02), and oxygen (02) concentrations, furnace temperatures, the sample mass weight loss, the average smoke particle diameter (dg and average number and concentration (no), and the product of the average smoke particle diameter and concentration (dgno). Results show that the inverse of the smoke particle diameter-concentration product [(l/dgn0)], correlates directly and significantly with the primary gas toxicities evolved during both early (HCI) and later (CO) stages of combustion.

Jan 1, 1989

By Fred D. DeVaney

The Mesabi iron district of Minnesota has a potential production of over 50 million tons of iron ore annually. The large shipments of ore each year are gradually depleting the reserves, and if the present rate of production is to be maintained there must be a growth in the present available ore supply. Growth is a natural course. The growth of a city may be affected by the addition of city blocks or by the improvement of utilities necessary for its betterment. These may go on in the order named or concurrently. The city-block type of growth of the Mesabi has been tremendous, and the "betterment" type has followed in due course. Probably the former has reached its limit, and if so, more time will be allotted to the latter. It is not the intent of this paper to present either a eulogy of the wonderful mining methods or a history of the milling, but it is pertinent to say that if the lean-ore area continues to produce, the continuance will be more the result of further improvement of milling methods now well under way than of extension, of boundaries by the city block plan of growth. In an examination of the western end of the Mesabi district one finds sludge basins containing millions of tens of millable ore rejected by washing plants which were built for economy in operating cost and with little thought of conservation, and rich tailings piles of jigging plant rejects. In addition, there is an appreciable tonnage of bowl rake products so low-grade that it requires mixing with the best ore of the district to make it merchantable.

Jan 1, 1932

By R. V. Ramani, R. A. Jankowski, R. Bhaskar

"The spatial distribution of airborne dusts, deposition of dust in the airway, as well as the effect of airflow velocity and particle density on dust behavior in mine airways were studied in a set of experiments performed in a mine airway under controlled conditions. Considerable deposition of dust near the source was indicated. Pronounced effects due to velocity were observed in ambient dust concentration and deposition along the mine airway, both in the respirable and the total size ranges. Cross-sectional concentration measurements indicate an increase in concentration from the roof to the floor. The average cross-sectional concentration is about 75% of the concentration in the center of the airway.IntroductionA number of studies have been performed since the early 1950s on the behavior of dust in mine air (Bradshaw and Godbert, 1954; Dawes and Slack, 1954; Bradshaw et al., 1954; Hall, 1955-56; Reinhardt, 1971; Ford, 1971; Courtney et al., 1982). While the experimental data available from these studies are indeed useful in understanding dust cloud behavior in a specific situation, no generalized conclusions can be drawn because of the lack of data on parameters such as flow velocity, size distribution of the source dust, and particle density. These change from mine to mine or even within the same mine. The present study is aimed at providing a better understanding of the temporal and spatial behavior of dust particles in underground' mine airways (National Academy of Sciences, 1980). The characteristics studied encompassed airborne concentrations and floor depositions over the entire size range as well as the respirable size range. The experimental results in this paper are intended to complement a mathematical model developed to predict ambient concentration and deposition of airborne dust in mine airways (Bhaskar and Ramani, 1986)."

Aug 31, 1989

By J. B. Gayle

The Bureau of Mines studied the effects of air oxidation on the recovery of float coal. Both batch-and continuous-type tests were made on six bituminous coals, representing the range in rank of coals now commercially used for carbonization, and on one anthracite coal. The effects on flotation recovery of oxidation at 1000 C for periods up to 50 days were investigated using an alcohol-type frother and a kerosine-pine oil reagent. Two series of release analysis tests were made, using one medium-volatile bituminous coal. Float coal recovery was adversely affected by oxidation in all tests where the alcohol-type frother was used. Conversely, a small degree of oxidation improved recovery with kerosine-pine oil frother for some of the coals in continuous tests. Prolonged oxidation (beyond about 14 days) adversely affected float coal recovery for all coals, the effect being more pronounced for batch-type tests and for tests using alcohol-type frother. Reagent selectivity for the rejection of both ash forming and sulfur bearing minerals was reduced by oxidation. Severe reduction of reagent selectivity required only about 3 days' oxidation for alcohol-type frother but more than 10 days' oxidation when the kerosene-pine oil reagent was used.

Jan 1, 1965

By E. P. Youngman

The basic mining law of Netherland India is contained in N. I. Statute 1899 , No. 214 , as amended by N. I. Statute 1910 , No. 588 , and 1919 , No. 4 , which is quoted as the " Indian Mining Law, " the effective date of which was fixed as May 8 , 1907 , by proclamation dated October 12 , 1906. The Indian Mining Law was supplemented by Ordinance No. 38 , of 1930 , which was passed by the Volksraad on March 18 , 1930 , to become effective on October 1 , 1930 ( superseding an earlier ordinance entitled " Government Gazette , " 1906 , No. 434) . An important law with respect to American petroleum rights , Statute No. 23 , passed February 9 , 1928 , approving contracts between the Indian Government and the Netherland subsidiary of a large American oil company , is in the nature of a private law or of an enabling act ( see section of this paper entitled " Rights of Foreigners" ) . Statute 1930 , No. 348 , effective October 1 , 1930 , sets forth in minute detail conditions under which prospecting and mining permits may be granted. Statute 1930 , No. 341 , effective October 1 , 1930 , embodies the police regulations of the mining industry.

Jun 1, 1931

By L. A. VANFLEET, Allen D. Look

The ever -present danger of mine fires and the possibility of hazardous atmospheric conditions in underground mines make a well-equipped mine rescue station a valuable asset to any mining district . Rescue equipment without proper maintenance provides only false security , because neglect may make the apparatus unfit for use in an emergency . Promptness in fighting mine fires is important ; frequently the first 30 minutes of action are worth many hours later . Likewise , the equipment will be of little value if enough men trained in its use are not readily available . This circular points out how such protection has been provided in an Arizona mining district by establishing a well- organized , adequately equipped , central mine rescue station. ·

Aug 1, 1950

By T. Ruff

Researchers at the National Institute for Occupational Safety and Health, Spokane Research Laboratory, studied technology and methods that could reduce accidents involving surface mining equipment that collides with other vehicles or workers, or drives over an unseen road edge. These accidents are partially attributed to the lack of full visibility around these large pieces of equipment. Blind areas can be extensive and this report presents plots of blind areas for five pieces of surface mining equipment. Several technologies designed for detecting obstacles in blind areas and providing a warning to the operator were evaluated on off-highway dump trucks. These proximity warning systems included radar, sonar, GPS, radio transceiver tags, and combinations of radar and cameras. A summary of test results is presented in this report, along with guidance on effective proximity warning technology, installation and maintenance considerations, and recommendations for effective implementation. This study found several commercially available systems that could effectively warn an equipment operator of an impending collision. Several new technologies also show promise for reducing these accidents. In most applications, it is recommended that sensor-based systems be combined with video cameras to provide important alarming functions along with an actual view of the blind area.

Jan 6, 2007

By C. J. Thompson

Two sulfur compounds--the 2,2,5-trimethyl- and the 2,2,5,5-tetramethyl derivatives of thiacyclopentane--were identified in Wilmington, Calif., crude oil, using microdesulfurization and gas-liquid chromtography techniques.

Jan 1, 1963

By R. V. Lundquist

A method was developed by the Federal Bureau of Mines for evaluating viscosity data from slurries obtained in leaching sinters from the lime soda sinter process for extracting alumina from aluminous silicates. The logarithm of the viscosity was observed to be a linear function with time. The slope of the plotted line provides a means for evaluating viscosity behavior in a lime soda sinter blurry and also a means for comparing gelation characteristics directly with other variables in the lime soda sinter process. This report presents one aspect of a continuing study by the Bureau of Mines on methods for treating siliceous aluminum ores. It is one of the many programs of the Bureau concerned with conservation, development, and use of our domestic minerals resources. Previous investigations of lime soda processes, both by the Bureau4-7/ and industrial concerns, have demonstrated that sintered materials containing CaO, Na2O, A1203, and S102 in various combinations exhibit a tendency to gel or set when mixed with water or other extraction solutions. Gelling prevents satisfactory recovery of alumina and in extreme cases prevents operation of an extraction plant.

Jan 1, 1960