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By Sean Gallagher

This report was written in an effort to provide better control measures for low back pain (LBP) and low back disability in the mining industry. There are numerous factors associated with development of LBP, many of which can be effectively controlled while some cannot. Better job design is promoted as the best method of reducing cases of LBP and can also reduce the disability (i.e., lost time from work) associated with LBP when it happens. The report draws attention to what is currently known about LBP, what the causes are thought to be, and discusses recent back injury trends in the mining industry. Research describing unique physical demands in mining, such as the capabilities and limitations of working in awkward postures, is also presented. Methods that can be used to prevent initial LBP episodes are provided, including facilities design and layout for materials and supplies, use of mechanical-assist devices, improved design of lifting tasks, and better seat design. Methods of reducing the disability associated with LBP (including workplace design, proactive return-to-work efforts, communication, and management commitment) are also discussed. The report concludes that control of LBP and disability in mining requires a comprehensive approach to limit the repetitive loading that can occur on the low back due to manual materials-handling tasks and exposure to whole-body vibration (WBV). Specific recommendations include the following: ? Successful LBP prevention efforts require a proactive program that has strong management commitment and incorporates employee involvement. ? More efficient supply handling systems and use of mechanical-assist devices can greatly reduce exposure to hazardous lifting tasks. ? Lifting tasks should be designed to minimize low back stress. Tools to evaluate and redesign lifting tasks are presented. ? Improved seat design can reduce exposure to WBV and improve posture, leading to reduced LBP risk. ? The disability associated with LBP can be reduced. Getting the worker back on the job as quickly as possible is in the interest of everyone involved.

Sep 1, 2008

The Full Scale Model Roof Bolt Test System described herein was designed, fabricated, erected, and installed by MSA Advanced Systems Division for the U. S. Department of Interior, Bureau of Mines, Spokane Research Center. It was furnished under USBM Contract No. 50271014 and Modifications. The test system is intended for use by the Bureau of Mines to run comparison tests on roof bolt systems. The mine entry cross section is made from special concrete pillars and roof slabs. They are constructed within a steel beam frame with hydraulic operated cylinders to apply loads that simulate the action of mining overburden. The frame is designed so it can be disassembled for replacing the concrete in subsequent tests. A computer and data acquisition system is furnished to control the load application and measure and gather data.

Jan 1, 1979

By R. R. Sayers

A series of coal- mine catastrophes in the latter part of the first decade of this century focused public attention on the need for safety in mines and resulted in the establishment of the Federal Bureau of Mines , whose primary function was to promote safety and improve hygienic conditions of workers in the mineral and related industries . These activities are carried out by the Safety Division of the Bureau's Health and Safety Service . In general , the work performed by the Safety Division personnel may be classified as educational and investigative . Instruction is given in accident prevention for mine officials and miners ; first aid to the injured ; the use and care of oxygen breathing apparatus ; and advanced mine rescue and recovery operations . A specialized safety course is offered to the petroleum and gas industries . Division personnel also aids in or directs rescue and recovery work after mine fires and explosions ; assists at first - aid and mine rescue contests ; conducts safety exhibits and demonstrations ; and presents safety talks , often accompanied by sound safety motion pictures or latern slides , before employee and official groups , at meetings of Holmes safety chapters , at mining institutes , and at other safety or technical gatherings . Coal - mine fires and explosions are investigated , as well as quarry or metalmine explosions and fires , miscellaneous accidents , health and safety hazards , and safety conditions at mines and plants ; safety devices are investigated and developed . Field studies cover ventilation , methods of allaying suspended coal - dust particles , prevention of dust accumulations , the proper use of rock dust to prevent or limit explosions , explosives practices , and the care and use of underground equipment . The results of these studies and investigations are widely applied in the various training courses and are prepared as reports and recommendations , which are submitted to interested persons or are combined and distributed to the public as bulletins , technical papers , miners ' circulars , information circulars , and reports of investigations . These studies also afford a basis for the development of new or modification of old Safety Decisions of the Mine Safety Board of the Bureau of Mines . The following pages review the accomplishments of the division as regards safety during 1942,2/ with like information for a series of recent years and summaries to date . A striking feature of the division's work has been the safety education of more than 1-1/2 million persons who have taken first -aid and mine rescue training courses . That these efforts over a period of 3 decades have been successful is revealed by the decline in coal - mine fatality rates and a somewhat smaller decrease in metal - mining and quarrying fatality rates .

Apr 1, 1943

By Jos. R. Guiteras

This paper is one of a series published by the Bureau of Mines on mining and milling methods and costs. It describes operations in the Alma district of Colorado in September 1937, supplemented by some additional data collected in July 1938. ACKNOWLEDGMENTS The author wishes to express his appreciation of the friendly cooperation extended him by the mine operators in the district. The greater part of the information was obtained from mine and mill superintendents to whom individual acknowledgment is made in the text.

Jan 1, 1940

By Jeffrey M. Listak

This U.S. Bureau of Mines report describes the implications of in-mine ground control on the automated or remotely controlled operation of longwall mining equipment, Perhaps the greatest challenge to longwall automation researchers is the development of systems that will continuously function in the complex and unpredictable underground environment. The high degree of environmental variability, together with conditions brought about by the extraction process, makes complete automation of longwall mining a difficult task. The intellectual thought processes and split-second decision making required to avert disasters are lost when workers are removed from the face. As many mine operators can attest, minor problems, left unresolved, can eventually accumulate and lead to catastrophic consequences. The automation process will have to assess and manage various routine problems that are otherwise resolved through worker observation and experience.

Jan 1, 1990

By R. A. Beall

This bulletin reviews the historical background of the cold-mold arc-melting technology, with specific references to the development that led to homogeneous zirconium ingots. Descriptions are given of modern production arc-furnaces for vacuum melting of troth exotic and conventional metals. Besides zirconium, specific data are given for production of chromium, thorium, and copper. The development of the skull-casting technique for titanium is detailed, and the application of the technique to such refractory metals as molybdenum and tungsten is described. Factors of operation of the apparatus and furnace design are considered.

Jan 1, 1968

1. BOYD, JAMES. Statement on the Investigation of Natural Resources. Hearings before National Re-sources Economic Subcommittee, Committee on Public Lands, U.S. Senate, 80th Cong., 1st sess., on Investigation of the Factors Affecting Minerals, Fuels, Forestry, and Reclamation Projects, May 15, 16, and 20, 1947, pp. 125-131. 2. BUCH, J. W., HENDRICKS, T. A., AND TOENGES, A. L. Statement on the Investigation of Natural Resources. Hearings before National Resources Economic Sub-committee, Committee on Public Lands, U.S. Senate, 80th Cong., 1st sess., on Investigation of the Factors Affecting Minerals, Fuels, Forestry, and Reclamation Projects, May 15, 16, and 20, 1947, pp. 231-235. 3. CONGRESS, U.S. An Act to Provide for the Establishment and Operation of a Research Laboratory in the Pennsylvania Anthracite Region for Investigation of the Mining, Preparation, and Utilization of Anthracite, for the Development of New Uses and Markets, for Improvement of Health and Safety in Mining, and for a Comprehensive Study of the Region to Aid in the Solution of Its Economic Problems and to Make Its Natural and Human Resources of Maxi-mum Usefulness in the War Effort. Public, No. 812, 77th Cong., 2d sess. (S-357), ch. 764, approved Dec. IS, 1942, 2 pp.

Jan 1, 1962

By Paul M. Tyler

The technology of clay and the manufacture of ceramic products therefrom, and also the clay resources of most of the individual States, are already covered by a voluminous literature. The present resume touches these matters only briefly; its purpose is essentially to bring together in small compass certain of the elementary factors affecting the potential commercial value of a clay deposit. In its preparation the author made extensive use of the annual chapters on Clay in Mineral Resources of the United States and in the two annual issues of the Minerals. Yearbook that succeeded them. For careful review and constructive criticism of the manuscript, the author is indebted to Hewitt Wilson. GENERAL DESCRIPTION The term ?clay? includes a great variety of substances that may differ widely in chemical mineralogical and physical properties. No two clays are exactly alike. All of them however, have the prominent characteristic of becoming more or less plastic when wet. Nearly all of the useful clays can be molded into articles, will hold their shape while being dried, and can be converted into a hard, rocklike substance by heat. Clay may, and in fact usually does, consist of a number of minerals among the commonest of which are kaolinite, quartz, feldspar, iron oxides, mica, bauxite, calcite, and manganese oxides. Organic matter is often present. Pure kaolinite, which has the formula A1203. 2 SiO2. 2H2O, is ordinarily, considered to be the parent "clay substance," butt most clays contain other hydrated mixtures of alumina and silica (aluminosilicic acids) along with indefinite amounts of sand and other nonessential minerals3/ Even, this so-called inert matter affects the plasticity, drying shrinkage, ease of drying, and final density, and at high temperatures may react chemically with the clay substance.

Jan 1, 1929

By John P. Capp

Information is summarized on the major uses of fly ash and prospects for utilization in agriculture and in brick and mineral-wool manufacture. Technological aspects of utilization are discussed and references are given to the work of many of the leaders in the fields of fly ash production, processing, and utilization.

Jan 1, 1970

By McMillan W. D.

Vermiculite is the name of a group of micaceous minerals characterized by their property of exfoliating when heated and thereby increasing many times their original volume. The resulting product has excellent heat-and sound-insulating properties, is used as a lightweight aggregate, and has numerous other industrial applications. Deposits of vermiculite occur in areas of pre-Cambrian rocks of the Llano uplift of central Texas, particularly in Burnet and Llano Counties. Because of the growing economic importance of vermiculite products, the Bureau of Mines undertook a detailed investigation of several deposits in Llano County. This investigation was completed in February 1947. The work comprised topographic surveys of five deposits, drilling with a 4-1/4 inch Parmanco power auger drill, and laboratory evaluation of samples. 342 drill holes, aggregating 4,905.5 feet, were completed, and 377 samples were taken. Laboratory evaluation of the vermiculite comprised expansion tests on both crude and beneficiated samples. The products obtained were compared with commercial-grade vermiculite from Montana.

Jan 1, 1949

By Joel N. Van Sant

An investigation was conducted to study possible sources of Utah refractory and structural clays that could be used for the manufacture of refractories and light or buff burning heavy-clay products. A field study was made and the clay samples tested to determine their firing characteristics. Results of the Bureau's work indicate many small noncommercial deposits of hypogenic clay occur in igneous rocks. Commercial hypogenic deposits are mostly halloysite clay developed by hydrothermal replacement of limestone. The high firing shrinkage of halloysite precludes its use as a refractory, however, halloysite produced at the Dragon Mine south of Eureka, is used fur making oil catalysts. Clays and shales suitable for low heat duty refractory products are found in the Manning Canyon shale, in shales associated with coal bearing rocks, and in the Dakota formation. Some of the clays from the Dakota formation are also suitable for high-duty refractory products.

Jan 1, 1964

In 1967 the United States consumed 58.8 quadrillion Btu of energy. Both the Atomic Energy Commission and the Resources for the Future, Inc., a private economic forecasting group, predict that the United States energy requirements will reach 135 quadrillion Btu by the year 2000. In 1967 bituminous coal produced 21.4 percent of the energy used in the United States and anthracite coal another 0. 5 percent. Coal Reserves Coal reserves make up about four-fifths of the United States storehouse of fuel in proven reserves. Seventy-five percent of all fuel, likely to be found and recovered is coal. Electric utilities consume more than half of the bituminous coal mined in the United States in generating 53 percent of the nation's electricity. Atomic Energy Commission analysts have proposed the development of a vast "national energy system" based upon long-distance electrical transmission from abundant untapped coal reserves in the western United States. The study predicts that even if uranium supplies are available and economic breeder reactors developed, coal requirements for electricity generation will more than double by 1980 and increase another 50 percent before the year 2000.

Jan 1, 1970

By Oliver C. Ralston, and others

"INTRODUCTION Investigations of the Nonmetals Division are now conducted at College Park, Md.; Tuscaloosa. Ala.; Seattle, Wash.; and. Norris, Tenn. The last of these was acquired, this year by arrangement with the Tennessee Valley Authority and is engaged in electrothermel research, using power generated by the T.V.A. and. raw materials from that region. In general, the work of the division is concerned with dressing nonmetallic minerals end utilizing the products there-from. Coal, salts, and waters are investigated, and the suitability of apparatus and equipment is studied.As the Metallurgical. Division of the Bureau of Mines makes routine tests of certain nonmetallic ores under prescribed conditions for the public if they are of general interest, the published reports of that division should be read and thus, with the reports of tile Nonmetals Division, the whole field may be covered."

Oct 1, 1939

By Merwin H. Howes

In constructing the NORAD Combat Operations Center, controlled blasting techniques were employed to achieve smooth walls and to avoid shattering the rock beyond excavation lines. Extraordinary measures were taken to stabilize the rock to permanently preserve the openings. Rock stabilization was accomplished by means of reinforced concrete and gunite linings, rock boltings, installation of chain-link fabric, and epoxy resin and cement grouting. A particular zone of weakness at B vital location was supported by exceptionally thick reinforced concrete lining, rock bolts, and cement grout.

Jan 1, 1966

Data recently released indicate substantial improvement in mineral industry performance for 1984. Business plans to increase plant and equipment spending in 1984 by 14.8 percent, according to a recent survey conducted by the Commerce Department's Bureau of Economic Analysis (table 1). In contrast, capital spending by all industries declined 4.8 percent in 1983 and 2.3 percent in 1982. The latest estimate of planned expenditures for 1984 is $2.2 billion higher than the comparable estimate based on the survey conducted in late January and February 1984.1/ [ ] Of particular significance to the U.S. mineral industries are the 15.5-percent increase in capital spending planned by manufacturing in 1984 and the planned 18.6-percent increase in spending by durable goods manufacturing, where the largest increases are planned in the transportation equipment (26.4 percent) and electrical machinery sectors (23.5 percent). Capital expenditures in manufacturing declined in both 1982 and 1983.

Jan 1, 1984

The purpose of this study was to examine the problems of underground coal mining in the United States, and to develop recommendations for an integrated Research and Development Program aimed at resolving these problems. Specific objectives of the study were as follows: ? To identify the existing inadequacies that have adverse effect on Health, Safety, External Environment, and Productivity. ? To identify opportunities for technological advance s to correct these inadequacies. ? To develop an integrated Research and Development Program designed to accomplish the advances identified. Many of the recommended tasks are dearly long range; this is especially true of those for study of future mining systems. However, funding recommendations in this Report are presented for a 5 -year period, since the developments accomplished during this period will undoubtedly be a factor in the formulation of the follow on tasks. Where applicable, the recommended Research and :Development could include development and test of pilot model equipment.

Jan 1, 1970

A compilation of papers presented at the Third WVU Conference on Coal Mine Electrotechnology in Morgantown, West Virginia, on August 4-6, 1976. Papers cover areas of electric power, electronic communications, detection and location of trapped miners, and electronic sensors and monitoring systems.

Jan 1, 1976

By J. R. Thoenen

This paper outlines briefly results of seismic measurements recorded in the vicinity of quarry blasting under practical operating conditions. The data cover field work done from January to the middle of August 1930, during which time records were made of 61 blasts in 19 quarries. Of the tests made, one was in biotite-gneiss, two in dolomite, two in a flintlike volcanic complex, three in gabbrodiorite, five in trap rock, and six in limestone. One quarry was in Alabama, two were in South Carolina, two in New York, four in Kentucky, five in Connecticut, and five in Massachusetts. Explosive charges ranged from 0.30 pound to 41,900 pounds, and the method of shooting varied from mud caps through hammer and wagon drill holes to churn drill holes and coyote tunnel shots.

Jan 1, 1937

By James T. McCartney, Joseph D. Davis

For more than 10 years coke-oven technologists have been investigating the expanding properties of coal on a scale larger than that afforded by laboratory test tubes. Koppers 4/ was among the first to realize that coals can not be differentiated satisfactorily with respect to expansion in coke ovens by the simpler test-tube methods; in his first method 80 grains of fine coal were coked in a cylinder heated from the bottom, so that the zone of fusion (plastic layer) advanced from the bottom to the top. The scale of test was too small; it has been modified by other investigators, but without significant improvement in practical application of the results. Somewhat later Koppers and Jendne 5/ experimented with a small-scale coke even, one wall of which was movable, in which the layer-coking in a coke oven could be simulated closely. This oven was heated from both sides. Their results with this oven showed a peak in the time-pressure curves near the end of the coking, period when the two plastic layers, advancing from opposite walls, meet. They also found that although the smaller oven was heated from one side only and did not show the Pressure peak characteristic of two-sided heating, it still gave results entirely too high. Russell built an oven similar to the movable-wall oven of Koppers and Jenkner and compared results obtained in it on Beckley expanding coal with these obtained on the some coal in the Altieri 7/ small-scale apparatus. Both tests were conducted at the same constant pressure, but heating was from two sides in Russell's oven and from one side in the Altieri tester. Russell found that the two types of test gave comparable results under constant pressure conditions even though the heating procedures were quite different. He showed later, however, that a "borderline" coal 8/ that contracted in the Altieri tester at constant pressure developed a peak pressure of 4 pounds per square inch in the movable-wall oven heated from both sides at constant volume. He concluded from this that testing at constant volume gave results more accurately indicative of dangerous expansion tendencies than those at constant pressure. He also found that heating from both sides in this oven gave higher pressure than heating from one side only.

May 1, 1942

By C. H. Larsen

The results of a comprehensive investigation of conveyance arrestment devices (safety catches) in United States coal mines are presented. Availability and use, performance, inspection, maintenance, testing, procedures, and regulatory requirements were investigated. Information was obtained from equipment manufacturers, mine operators, and regulatory-agency personnel, as well as from studies of domestic and foreign mining safety regulations. Traditional mine hoists and commercial elevators for mine use were investigated. Results of this and an earlier study of wire-rope practice in United States coal mines show a continued need for conveyance arrestment devices. A wide variety of these devices are in use. Only two types have been proved reliable for stopping a conveyance without injuring passengers or equipment. These are elevator overspeed-actuated wedge-clamp (Type B) safeties and broken-rope-actuated devices for wooden guides using a single-tooth-dog design developed in Ontario as a braking element. Elevators are widely used in U. S. coal mines. When maintained according to American National Standards Institute (ANSI) Specifications A17. I and A17. 2, they appear to present no major arrestment problems. Of 42 coal-mine hoists used for man transport that were inspected, 30 are in vertical and 12 in inclined shafts. Twenty-four vertical shafts use wood guides; 6 use steel. The 12 inclined-shaft systems use flanged-wheel T-rail guidance. Two wood-guided vertical-shaft systems use the single-tooth Ontario-type dog; the other 22 use multi-toothed wedges, cams, or dogs that have been proved highly unreliable. The arrestment devices in the six steel-guided vertical-shaft systems and in six of the inclined-shaft systems cannot be evaluated because performance data are lacking. The remaining six inclined-shaft systems have no arrestment devices at all. Of the 36 hoists with arrestment devices, the devices of 16 are never tested, the devices of 10 are actuated periodically with the conveyance at rest, and the devices of the other 10 are actuated periodically with a slow-moving conveyance. Although high speed is as probable as low speed in an emergency and would provide the best test of arrestment capability, no tests are performed in the United States which demonstrate the ability of an arrestment device to stop a loaded conveyance from high speed. Mine operators indicate little confidence in their conveyance arrestment devices, and manufacturers recognize a need to improve their products. Neither state nor Federal regulations provide a guide to this improvement. Mine operators, manufacturers, and state and Federal regulatory agency personnel would welcome specific guidance. In view of this, a set of application, design, actuation, stopping-performance, and testing and inspection criteria is presented as a guide to eliminating the inadequacies of these devices. Recommendations are included for improving hoist controls and machinery directly affecting conveyance safety.

Jan 1, 1972