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By George S. Rice

In response to numerous requests for information as to the status of internal-combustion mine locomotives of the Diesel type that use heavy or non- volatile oil for fuel, with special reference to their safe use in coal mines, the United States Bureau of Mines is issuing this report. Data mere obtained, on application of such locomotives to cod mining only in Belgium, France, Germany, and Great Britain. The locomotives are used in coal mining in other countries, as well as in potash, iron, and other kinds of mining, but their chief development has been in coal mining in Germany, France, and Belgium. Recently popular interest in the Diesel type of engine for motive purposes was aroused in this country by the successful application of Diesel engines to railroad locomotives hauling fast transcontinental trains, and, according to published statements, at a low cost of fuel per mile of run.

Jan 1, 1936

By R. M. Becker

THIS IS a progress report on a study of the application of statistical practice to mine and mineral sampling undertaken by the Federal Bureau of Mines to provide sound theoretical and practical data for use of the mineral engineering professions. One of the problems in mine sampling is determining the reliability of the results. For certain types of sampling data (random data) the reliability of the results can be stated mathematically. For other types of data there is no known means of quantitatively expressing reliability. In applying measures of reliability to a set of random data, some knowledge or assumption of the characteristics of the particular data is necessary. In many fields these characteristics are well known. However, in mining, where the data are in assays, these characteristics are not well known.

Jan 1, 1961

By G. E. McElroy

[The ventilation of development faces In nines for diluting Gas or dist concentrations and, in hot nines for providing air-motion cooling effect, by fan-pipe units discharging high-velocity steams of air close to the face, is an important phase of mine ventilation. The effectiveness of such units depends largely on the air-flow distribution between the pipe discharge and the face, n subject on which little definite information is available. A study of the air flow from grills into rooms3/ has provided some basic data, but under conditions so different from mine fan-pipe installations in development ends that the data are of doubtful application to mine installations, owing to differences in air-flow conditions.]

Jan 1, 1940

By Alden H. Emery, J. J. Forbes

"IntroductionThe data contained in this paper were collected during the course of an investigation which covered 15 representative coal mines in 6 coal-mining States. The purpose of the investigation was to determine by atmospheric sampling how much dust was raised into the air during the various operations of coal mining, such as undercutting with machines, loading coal by hand, and transporting it from the working face to the surface. The data thus obtained were considered from two angles - namely, the possible physiological effect of inhalation and the explosion hazard of the dust. No attempt will be mode to discuss the former factor in this paper.CONDITIONS OF MININGThe mines in which this investigation was conducted were considered representative, and it is believed that the results obtained will suffice for the average dustiness encountered in most coal mines. .All of the coal mined was bituminous, from beds 30 to 120 inches thick. Only the ordinary room-and-pillar system of mining was employed. Daily production ranged from approximately 700 to 1500 tons and the men employed from 150 to 450. Coal was undercut by short-wall mining machines in all mines, with the exception of one in which pick mining was employed. Loading at the face was done by miners; none of the mines used mechanical loaders. Electric drills, both for brushing roof and for shooting coal, were commonly used although some roof work was done with jack-hammers and a. little of both with augers. Coal was hauled by motor, mule, or rope power in end-gate cars with capacities ranging from 1600 to 3600 pounds. With few exceptions, coal was won at the face by dry methods - that is to say, no water was employed fox wetting down the dust either during undercutting, loading, or transportation."

Feb 1, 1927

By T. L. Joseph

The Bureau of Mines gas been studying the blast furnace for a number of years and has published detailed reports on various phases of its investigations. Inquiries frequently received for information of a more general character than that given in the detailed reports have promoted the preparation of an information circular to cover in a general way the important features of the Bureau of Mines blast-furnace investigations. SHAPE AND DIMENSIONS OF FURNACE The modern blast furnace approximate a refractory-lined steel cylinder about 90 feet in height and 25 feet in diameter. It actually consists of a number of cylinders and truncated cones superimposed upon each other. The shape and dimensions of a modern furnace are shown in figure 1. The bottom section, commonly referred to as the hearth or crucible, is a cylindrical section about 12 feet high. Liquid metal and slag collect in this part of the furnace and are withdrawn at regular intervals; iron is removed at a level about 2 feet above the bottom of the furnace and slag at a level about 5 feet higher. Depending upon on the size of tie furnace, 40,000 to 75,000 cubic feet of preheated air per minute is introduced through from 10 to 16 tuyeres equally spaced around the periphery of the hearth.

Jan 1, 1934

By Fei-chiu Huang

The principle of time domain reflectometry (TDR) is being used by the U.S. Bureau of Mines to monitor strata displacements induced by mining. The Northwestern University TDR Signature Analysis (NVTSA) Program was developed under contract with the Bureau to allow for visual comparison of three TDR waveforms quickly and easily. This program is interactive, and on-line help is available. The Northwestern University Remote Control TDR Data Acquisition System and Modification of Tektronix SP232 Host Application Program (NUMOD) was then developed to allow acquisition of TDR wave-forms from a remote cable tester via modem. The NUMOD system utilizes commercially available software while the NUTSA program is available from the Bureau. This report begins with a discussion of TDR principles followed by a description of the NUMOD system. An interactive example of signature analysis is then used to demonstrate features of the NUTSA program.

Jan 1, 1993

By J. J. Demeter

Experiments were conducted in 2- and 4-inch-diameter standpipes to evaluate the effectiveness of standpipes as pressure seals. During the experiments, these standpipes conveyed Alan-Wood magnetite (60 to 230 U.S. standard sieve mesh) by gravity flow from one vessel to another of relatively higher pressure. The information obtained has been helpful in a Federal Bureau of Mines investigation of how to make either synthesis gas or hydrogen by a modified steam-iron process employing a continuous recycling stream of granular iron-iron oxide at temperatures of 600° to 900° C. In this process the mixture of granular material flows by gravity from a reduction vessel at low pressures to an oxidation vessel at higher pressures. Data from the 2- and 4-inch-diameter standpipes indicate that it would be practical to use a standpipe as a pressure seal between the reductor and oxidizer. Investigators found that, by gravity flow, the standpipe could convey the Alan-Wood magnetite against pressure gradients up to 1.07 pounds per square inch per foot of column height.

Jan 1, 1961

By A. C. Johnson

This circular is one of a series published by the Bureau of Mines describing mining and beneficiation methods and costs at various mining operations throughout the United States. Inclusion of the Abbott mine in this series is of particular interest, as the complex geology and the character of the deposits make their exploitation a unique operation. The mine operates on a high-cost, comparatively small-scale basis, and only the persistence of an aggressive management has enabled it to maintain its rank among the major mercury producers of California. Rising costs and decreasing metal prices, which continuously threaten the low profit margin, are reflected in increased efficiency of operation. This report summarizes past operations and describes, in detail, the geology and ore deposits; exploration and mining methods; and furnacing and condensing operations. It covers the entire operation from initial exploration to the actual production of mercury. Comparative production costs for 1944 and 1958 are of special interest.

Jan 1, 1962

By N. A. Eilertsen

Procedures of mining high-calcium limestone underground at the Kimballton mine of the Standard Lime and Cement Co. in Giles County, west-central Virginia, are described. Drilling and blasting procedures arc discussed in detail, and direct mining costs are tabulated in percentage of total cost. Output, about 1,725 tons of limestone a day, is attained with heavy trackless equipment by the room and pillar method of ruining; modified by benching floors. Operating features include underground air compression, electric-eye control of curtained doorways, use of a single jumbo drill rig for all drilling, and an effective plan for maintenance of equipment. The company's safety program has contributed to an outstanding safe mining record. The mina is integrated with a plant on the property which converts the stone to metallurgical and chemical grade lime.

Jan 1, 1964

By T. E. Gray

This report describes preparation characteristics of the significant coalbeds in Marion County, W. Va., as determined by the Bureau of Mines. It is one in a series telling what coals are suitable for producing metallurgical coke, either as mined or after beneficiation. Over 9.4 million tons of coal was produced in Marion County, W. Va., in 1958, of which almost 6 million tons was cleaned mechanically in nine cleaning plants. All of the coal mechanically cleaned came from the Pittsburgh bed. The Bureau of Mines estimated that 1,578 million tons of recoverable coal remained in the county in beds 28 inches or more thick as of January 1, 1955.

Jan 1, 1960

By W. A. Calhoun

This report gives results of metallurgical investigations performed by the Bureau of Mines on mineral samples taken during April 1959, from Hawaiian bauxite deposits on the islands of Kauai, Maui, and Hawaii. The bauxite samples were tested at the Bureau's Rolla Metallurgy Research Center, Rolla, Mo., to determine if alumina could be extracted. The results were encouraging. Extraction of the alumina by the American Bayer type digest of crude ore samples from Kauai, Maui, and Hawaii recovered 78.8, 73.1, and 70.0 percent, of the total alumina, respectively. These recoveries were increased to 82.8, 85.5, and 79.5 percent by modifying the treatment, which consisted essentially of calcination and weak caustic desilication to provide a residue. The residue was then treated with calcium oxide and digested in a strong caustic solution to extract the alumina.

Jan 1, 1962

By Sara Jane Boles

In recent years the demand for products of greater refractoriness has placed an ever-increasing emphasis on ceramic materials, including the metallic oxides. Magnesia (MgO) is one of the most important of these oxides, exhibiting, as it does, high electrical resistivity, high slag resistance, and a melting point of 2,800° C. However, magnesia has a tendency to hydrate in the presence of water and to volatilize above 1,500° C. in certain kiln atmospheres and has a comparatively low resistance to thermal shock. Because of these disadvantages, the previously listed advantages inherent in this material have been largely overlooked, and research on magnesia has lagged behind that on oxides such as alumina and zirconia. This bibliography has been prepared in an effort to present to Government and industry a comprehensive picture of the prospects for greater utilization of magnesia as a refractory material in future research. To provide as selective and accurate a collection as possible, the references included cover magnesia in a pure state, not as an additive or in combination with other materials. However, several references discuss the effect of minor impurities (less than 5 percent of the total) on the properties of magnesia, as these papers are considered to be of special importance. A few references to articles on forming techniques are also included, as they are valuable additions to the overall treatment of the subject. The processes used in obtaining and refining the raw materials are adequately covered in earlier publications and are excluded. A number of references are omitted as being of questionable value in enhancing the cumulative study of pure magnesia as an ultra-high-temperature refractory material.

Jan 1, 1962

By Allen L. Frank

The uranium mine environment is characterized by airborne radon-222 and its daughter products to which miners are exposed through breathing and by gamma and X rays from the uranium-235 and uranium 238 chains to which the miners are exposed externally. The nature of the radon-daughter concentrations and the methods used to define and measure the exposures are explained through an extensive review of the literature. An improved passive track-etch dosimeter for personal use is proposed which has a measurement range of about 30-400 WLH with a 95% confidence interval to ~25% for individual detector measurements in relatively stable mine air. Some measurements of these dosimeters adapted to environmental use are also presented. A program of development for enhancement of dosimeter sensitivity and greater accuracy of measurement is outlined. Extensive gamma-ray survey measurements were made in two Colorado and three New Mexico mines. Follow-up personal miner dosimetry with LiF TLDs was done at the mine with the highest exposure rates, The average miner exposure rate measured was 4.27 mR per day, or 9.3 of the maximum permissible level averaged over 13 weeks. Comparisons are made with previous mine surveys and their value in estimating miner exposure is discussed. Some depth-dose measurements made using Lucite as the absorber are evaluated.

Jan 1, 1978

The objective of this study was two-fold: 1. To perform a world literature search pertinent to the analysis, selection and design of hoisting systems and their components and to codify the search into a literature compendium. The search resulted in a technical data file of over 1500 hard copy items. The compendium index was also suitable for establishing a comprehensive computer-loaded data base on the subject. 2. To develop a comprehensive system of guidelines to cover salient aspects of analysis, selection and design of electrical, mechanical and structural components of a hoisting system with a view to establish parameters for maximum safety and efficiency of operation, installation and revision of the system. 3. Major mechanical components in the hoist and mechanical drive train are considered. Design and specification criteria based on American standards and practices are developed as they apply to typical mine hoist arrangements.

Jan 1, 1988

By Doris M. Hyde

The economy of Belize continued to show a very slight but still positive growth during 1986. The gross domestic product (GDP) was estimated to have been about $164 million,2 almost the same as those of 1984 and 1985. Foreign investors looked favorably on Belize because it had remained isolated from the sometimes turbulent political and social strife elsewhere in Central America. Reportedly, in late 1986, Guatemala had decided not to pursue its claim to Belizean territory and to give full recognition to that country. Discussions were to be held regarding any matters of mutual concern. New investment possibilities were oriented toward agriculture or manufacturing endeavors. Except for some interest in petroleum exploration, the minerals sector remained limited to the quarrying of construction-related materials.

Jan 1, 1988

By T. F. Anstett

The Bureau of Mines estimated the potential availability of tungsten from 57 mines and deposits in 19 market economy countries. The tungsten resources of China and the U.S.S.R. were also estimated. This resulted from an evaluation of tonnage-cost relationships indicating the quantity of tungsten available as ammonium paratungstate (APT), artificial and natural scheelite, and ferrotungsten at various average total costs of production including 0- and 15-pct rates of return on invested capital. The evaluated deposits contain 1.2 million metric tons (t) of recoverable WO3, of which approximately 52,000 t of AEYT can be produced at the January 1983 market price of $5.37/lb, 89,000 t of natural and artificial scheelite at a market price of $3.63/lb, and 1,700 t of ferrotungsten at $5.61/lb of tungsten. An annual availability analysis indicates that by the early 1990's new deposit discoveries, development of known prospects, or expansions of producing mines will be necessary to meet projected tungsten demand.

Jan 1, 1985

By Allan F. Smith

The influence of hydraulic fluids on spontaneous heating in bituminous coals is determined by measurement of the temperature increases produced in coal-fluid mixtures heated to a temperature sufficient for the initiation of self-heating. Similar tests on as-received coal samples and water-coal mixtures are compared with the results obtained for the various hydraulic fluids. Three of the four coals were sampled from coalbeds known to have a history of spontaneous heating. The data provide a basis for predicting the possible effects in gob or carbonaceous refuse of coal mines.

Jan 1, 1963

By E. L. Garton

[AnalY3e s of Qany crude t) i 1 s prod.uced in Loui sia.na are incl udeo" in re!Jor~ ~ th'l t have b en u~li shed by the BurOllU 0: i?{ine s. The first rc-port,j} givin..; analyseG of 6 Louisiana crude oils, '-vas pUblluhed in 1921'l.s,nd this was 1'0110\ cd a year later by P.ep rt of InvBstign.tions 21a6t~ givi~ 7 addi tional analyses. The G7even :,ost il'!lportant of these analyses were incol"]lorated in Bulle~in 91,.2, is~ued in 1928. In 1934, analyses of 26 cl ... ude oils j)roduced in southern Louisiana ",ere published ? .§! The present report I)renonts analysos of 72 ad(~itional samples of crude oil frorl 4-, fields in 23 "l)ari shefl in Loui f",io.r]

Jan 1, 1939

By S. H. Lorain

This paper is one of a series being published by the Bureau of Mines describing the mines and mills and subjects related to mining in western mineral areas. Although mining districts in the Tobacco Root Mountains are numerous there is a strong similarity in the character of the ore deposits and in the climatic and economic conditions affecting mining throughout the region. Individual mines are small, but the production of lode mines

Jan 1, 1937

By Chris Jobes, Alan Mayton, N. Kumar Kittusamy, Dean Ambrose

NIOSH researchers conducted a study to compare seat designs on underground coal mine haulage vehicles. The objective of the study was to support prior findings that NIOSH-designed seats, which incorporated ergonomic design features (e.g., viscoelastic foam padding and low-back support), are improved designs. Based on measured levels of vehicle jarring/jolting and perceived discomfort, researchers evaluated four different designs - two in-use and two NIOSH-developed, ergonomic designs. Researchers collected data using a short questionnaire, a linear, visual analog scale, and accelerometers with a data recorder. Results showed that vehicle operators favored the NIOSH seats with added adjustability, low-back support, and improved seat padding over the existing seats. In addition, the measurements indicated all NIOSH seats performed better than the existing seat, under the no-load (worse of two) conditions, in reducing peak acceleration, crest factor, and RMS acceleration. The authors summarize the data collected and operator preferences for seat designs and different foam padding arrangements.