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By F. H. Willcox

This publication is the third of a series of reports on hazards and the prevention of accidents at blast-furnace plants that is being published by the Bureau of Mines, Technical Paper 106a being the first and Technical Paper 136b the second of the series. This bulletin, which is arranged in three parts, treats of the causes and prevention of blast-furnace breakouts, explosions, and slips. The first part discusses blast-furnace breakouts, the hazards therefrom, causes, and features of furnace design and methods of operation that tend to prevent breakouts or lessen their number, and points out safety measures to be adopted. The second part takes up the theory and causes of gas explosions at blast-furnace plants and reviews the better methods in use for handling gas. The third part analyzes the causes of hanging and scaffolding in blast furnaces, with the resulting slips that frequently cause injury to the plant and danger to the workmen, describes features of construction and furnace design and methods of operation employed to prevent hanging and slipping, and suggests precautions and safeguards.

Jan 1, 1917

By Lucia Kuizon

The Pinnacles Wilderness Contiguous Wilderness Study Area (WSA) (CA-040-303) is 30 miles south of Hollister, CA, in San Benito and Monterey Counties. It is composed of five parcels of public land totaling 5,838 acres adjacent to the Pinnacles National Monument. The U.S. Bureau of Land Management later reduced the size of the Recommended Suitable Area (RSA) to 2,200 acres. U.S: Bureau of Mines personnel examined the entire WSA in May 1984. The WSA is underlain by Tertiary sedimentary and Cretaceous plutonic rocks. Diatoms occur in interbedded tuff, shale, and sandstones in the northern part of the WSA, but outside the RSA. In 1984, there were no mines, prospects, mining claims, leases, or mineral resources in or within one mile of the study area. No energy minerals were identified; however, an oil well was drilled in 1951 in the northern part of the WSA, but outside the RSA; it was a dry hole.

Jan 1, 1985

By PW Meisel

An hydraulic-powered reel system to minimize peak tension transients in shuttle car trailing cables has been theoretically designed and analyzed using a computer. A single spring-loaded take-up sheave stores or gives up cable to maintain tension within specified limits. Controls have been incorporated to shut down the vehicle before all cable is removed from the reel and to de-energize the cable in the event of a reel/cable jam. Full-scale hardware configuration drawings sufficient for manufacture of a test system have been completed.

Jan 1, 1983

Significantly increase the amount of fresh air that sweeps the face in front of a continuous mining ma-chine, in order to prevent methane gas buildup. Approach Water sprays are mounted along the sides of a continuous miner and behind the cutter head to help push ventilating air along the required path, and prevent its short circuiting. How It Works A continuous miner is fitted with two sets of water sprays, one of which is used at a time. The set of sprays shown in the diagram, helps move the ventilating air forward along the left side of the miner and across the cutter drum from left to right. That air is then drawn into the exhaust air passageway located along

Jan 1, 1978

By William N. Patterson

This report describes the design and testing of an improved quiet hard rock percussion drill. The improved drill incorporates a tappetless design with independent rotation in a hand held drill weighing 50 lbm. Laboratory and field testing in three mines were conducted. The testing showed improved drilling performance with no increase in measured noise levels over the fist design.

Jan 1, 1985

During the period 1979 thru 1982, Multi Mineral Corporation conducted a mining research program at the United States Department of the Interior's Bureau of Mines Oil Shale Mining Environmental Research Facility in the Central Piceance Creek Basin, Rio Blanco County, Colorado. The program consisted of mining, environmental and geotechnical research data and the results are described in this report.

Jan 1, 1983

By John P. Hansen

Batches of red or brown iron ore concentrates, weighing 100 or 200 grams, were reduced with gaseous reductants in a laboratory-sized fluidized-bed reactor. Using a loss of weight technique, the rates of reduction were measured and the effects of temperature, gas consumption, and gas flow rates were determined. Below about 725° C the rate of reduction was controlled by the chemical reaction at the reduction interface having an activation energy of about 10 kcal/g mole. Above about 725° C the rate of reduction appeared to be controlled by the flow of the gaseous reductant and therefore to be directly proportional to the flow rate. Above 725° C, hydrogen reduced the iron ore much faster than carbon monoxide. In gas mixtures, carbon monoxide or nitrogen reduced the hydrogen partial pressure and lowered the reaction rate proportionally. When present in large concentrations, carbon monoxide had a serious inhibiting effect on the reduction rate, probably owing to carburization and sintering of the reduced iron.

Jan 1, 1970

By Compiled by Staff

"INTRODUCTIONThe U.S. Bureau of Mines (USBM) was established in the public interest to conclude inquiries and scientific and technologic investigations on mining and the preparation, treatment, and utilization of mineral substances; to promote health and safety in the mineral industries; to conserve material resources and prevent their waste; to further economic development; to increaseee efficiency in the mining, metallurgical, quarrying, and other mineral industries; and to inquire into the economic conditions affecting those industries. The organic act of the Bureau, as amended by Congress and approved February 25, 1913, made it the province and duty of the U.S. Bureau of Mines to ""disseminate information concerning these subjects in such manner as will best carry out the purposes of this Act.""In accordance with this directive, USBM reports the findings of its research and investigations in its own series of publications and also in articles that: appear in scientific, technical, and trade journals; in "" proceedings of conventions and seminars; in' reference books; and in other non-USBM publications. The number of these reports, the wide range of subjects they cover, and the variety of mediums in which they appear make this kind of list both necessary and valuable.This edition describes reports and articles published during calendar years 1992 and 1993. It supplements the 50-year list of Bureau publications from July 1, 1910, to January 1, 196O 2; and these 5- year lists of publications and articles: from January 1, 1965, to December 31, 1969 4, from January 1, 1970,to December 31, 19745 , from January 1, 1975, to December 31, 1979 6 , from January 1, 1980, to December 31, 1984 7 , and from January 1, 1985, to December 31, 1989 8."

Jan 1, 1994

By M. S. Fleming

The objective was to evaluate central lubrication systems for potential use on underground mining equipment. Previous use on continuous mining equipment resulted in poor system performance because of improper selection of lubricants, component failures, and an inconsistent delivery of lubricant to the bearings. The principles and operational characteristics of systems are reviewed and evaluated, and it was concluded that systems are available which can provide reliable central lubrication if properly applied, installed, and maintained. The procedures for applying a system to a continuous miner are discussed. Investigation revealed the lack of significant information on lubrication-related equipment failures and injuries related to maintenance and repair operations, the lack of significant failure rate data for central lubrication system components, and the lack of performance standards for central lubrication systems and components. To continue the development of systems for underground mining equipment it is recommended that a data bank on failures and reliability for equipment with and without central lubrication systems be created, and standardized specifications and performance criteria be developed for central lubrication systems and components which will be used on underground mining equipment.

Jan 1, 1979

By R. E. Mussier

This investigation was made to study new methods to prepare high-purity yttrium metal, Various methods were used to prepare pure intermediate compounds, primarily chlorides, bromides, and iodides, which were subsequently reduced to metal. The process found most suitable for the preparation of pure anhydrous yttrium chloride involved thermal dehydration of a mixture of hydrated yttrium chloride and ammonium chloride while under vacuum. Yttrium bromide and iodide were prepared most effectively by the direct halogenation of yttrim carbide. Yttrim carbide was obtained by reacting and melting yttrium oxide-carbon mixtures in a carbon-arc furnace. Yttrium halides were purified by vacuum distillation and reduced by alkali or alkaline-earth metals. Lithium and sodium proved to be the best reductants from the standpoint of yield (>95 pct) and purity (>99.8 pct) of the yttrium. The product of the reduction step was sponge metal, which was consolidated readily by conventional cold-mold, arc-melting procedure. The purest yttrium obtained in laboratory scale work was prepared by sodium reduction of yttrium chloride and contained only 125 pp oxygen; other impurities did not exceed 1,000 ppm. In larger scale tests yttrium containing only 800 to 1,000 ppm total impurities was obtained by lithium reduction of yttrium chloride. The tensile properties of high-purity yttrium were determined. Mechanical tests showed that yttrium can be forged, extruded, rolled, spot welded, and deep drawn.

Jan 1, 1963

By M. F. Dunn

During a mine fire or other emergency, it may be desirable to reverse the airflow in order to provide an escapeway or to isolate a fire. Also, in colder areas, the airflow may be reversed to prevent ice buildup. When reversing main mine fans, the mine operator usually does not know what operating characteristics of flow and pressure to expect. Laboratory and field tests of vane axial main mine fans in the 7- to 9-ft diameter size range were conducted to establish forward and reverse performance characteristics under controlled conditions and at typical mine installations. The data obtained suggest that reverse performance characteristics are dependent upon the blade angle and the hub to tip ratio. There is also evidence that reverse performance can be predicted for a family of blade angles and a given hub to tip ratio. Generally, quantity of air is 30 to 65% less in reverse than when operating in the normal forward mode.

Jan 1, 1983

By Maria I. De Rosa

Analysis of mining equipment fires from 1990 through 1999 reveals that there were 340 large mining equipment fires, resulting in 72 injuries and five fatalities. Many of the fires resulted in the loss of equipment and all posed potential or real risks to the operator. In 97 cases, the fires raged out of control due to engine shut­off failure, even upon activation of the machine fire suppression system, due to the spraying of pressurized hydraulic flu­id and fuel onto hot engine surfaces. In other cases, even after engine shutoff, the fires re-ignited, fueled by the contin­ued flow of flammable fluids remaining in the lines onto the hot engine surfaces. In many of the fires, flammable vapors evolved and penetrated the cab, violently igniting, forcing the operator to exit under very hazardous conditions. The use of emergency evacuation lines in the fuel and hydraulic fluid systems, and methods to reduce or prevent the spraying of pressurized fluids onto hot engine surfaces would greatly improve the chances of successfully suppressing large mining equipment fires. In addition, the use of systems for preventing the ignition of flammable vapors inside the cab, and detecting and suppressing fires originat­ing in the cab, would greatly enhance operator safety. The National Institute for Occupation Safety and Health (NIOSH) recently conducted experiments on meth­ods to reduce the fire hazards associated with large mining equipment. These experiments evaluated the use of cab inerting systems to prevent the ignition of flammable vapors inside the cab and sup­press fires originating in the cab, while maintaining a breathable atmosphere for the operator to bring the equipment to a stop and safely exit the cab.

Jan 1, 2008

By William G. Pariseau

A brief description of a two-dimensional elastic-plastic finite element program intended for mine stability analysis is presented that includes detailed instruction for input data preparation and how to obtain output.

Jan 1, 1978

By H. H. Dewing

The U.S. Bureau of Mines characterized Hg-containing wastes and used a thermal-desorption process to remove and recover the contained Hg. The wastes were generated by an electrical-parts plant engaged in the assembly of Hg-containing switches and contained phenolic resins and paper insulating materials mixed with soil. The average Hg content was 396 ppm. Numerous characterization tests showed the Hg was tightly absorbed and could not be removed or concentrated by leaching or gravity separation techniques. Laboratory retort tests showed the Hg content reduced to < 16 ppm in 2 h at 400 °C; rotary-kiln, thermal-desorption tests required 4 h at 450 °C. Airflow through the retort im¬proved thermal-desorption efficiency, but vacuum operation only slightly reduced the temperature needed for thermal desorption. Offgases from decomposition of organic materials were burned in a high-temperature afterburner and subsequently cooled in a heat exchanger to condense water vapor. Finally, the Hg vapor was condensed and absorbed from the offgas by activated charcoal. Mercury recovery was over 99.99 pct of the desorbed Hg. Thermal-desorption processes have had wide application to many Hg-containing wastes, and historical experience in Hg mining has demonstrated its potential cost effectiveness.

Jan 1, 2010

By A. H. Shoemaker

This paper describing the mining practices at the Old Dominion mine, Globe, Ariz., is one of a series being prepared by the United States Bureau of Mines on mining practices, methods, and costs in the various minim districts in the United States. The Old Dominion mine is situated in the eastern port of the Globe-Miami district, about 1-1/2 miles north from the center of the town of Globe. An average of nearly: 1,200 tons per day was mined during 1928. The prevent production is about 1,500 tons per day; of this amount,, approximately 100 tons is direct-smelting ore that is shipped to the smelter at Miami and 1,400 tons milling ore which is treated in the company?s concentrator at Globe. About 600 men are employed at the mine.

Jan 1, 1930

By Robert L. de Beauchamp

The Bureau of Mines designed a chlorination apparatus to prepare CrCl2 free of CrCl3 by the direct reaction of chlorine and chromium. Equipment and procedures were developed for routine preparation of 25-pound batch quantities of anhydrous CrCl2. Calcium, iron, nickel, and silicon impurities were in the 0.01 to 0.05 percent range, and all other impurities were below 0.01 percent.

Jan 1, 1968

This appendix is composed of five sections, each of which is tabbed for ease of access. The sections are as follows: ? Fire incident report forms for underground mine fires. There is one form for each incident listed in Table II-1a. They are ordered chronologically with incident numbers corresponding to those in Table II-la. ? Fire incident report forms for surface mine fires. There is one form for each incident listed in Table II-lb. They are ordered chronologically with incident numbers corresponding to those in Table II-lb. ? Journal article report forms. There is one form for each article reviewed. They provide supplemental information to that contained in the fire incident report forms for selected fires. Index 11-14 keys the journal article report forms to the appropriate fire incident report forms. ? Non-reportable incident descriptions for underground mine fires. This is a listing of underground fires for which MSHA regulations do not require formal reports. ? Non-reportable incident descriptions for surface mines. This is a listing of surface fires for which MSHA regulations do not require formal reports. This appendix is intended to be used in conjunction with the tables and indexes contained in Volume II of this report and, as such, should be considered an integral part of Volume II. The indexes in the body of Volume II provide a means of ready reference to the underground and surface mine incident report forms. For those readers with interests other than those indexed, Tables II-la and II-1b can be used to locate specific incidents of interest. Complete incident information can then be obtained from the corresponding report forms in the first two sections of this appendix.

Jan 1, 1980

Humankind&apos;s interest in measurement of human physical strength probably dates to the first humans. At that time, life was truly a struggle in which the fittest survived. To a great extent, fittest meant strongest. Interestingly, current interest in human physical strength in the workplace stems from 1970-1980s vintage research demonstrating that persons with adequate physical strength are less likely to be injured on physically demanding jobs. Survival in many modem workplaces may still be a case of survival of the strongest. There is, however, a flip side to this issue - that persons with limited strength are more likely to be injured on "hard" jobs. To address this problem, we can apply what we know about physical strength to job design. "Hard" jobs can be redesigned to be within the physical strength capability of most people. Since physical strength is important to these jobs, we must find ways to quantify it through testing. This publication concerns human physical strength testing. Its purpose is not to recommend any particular type of testing, but rather to describe the types of testing available and their uses. It is up to each individual user of strength testing to decide which testing technique is most appropriate for his or her particular application. This booklet discusses four types of strength testing: isometric, isoinertial, psychophysical, and isokinetic. Human Strength Before describing the different types of strength measurement, we must define the term "strength" and explain the concept of strength measurement. Strength is defined as the capacity to produce force or torque with voluntary muscle contraction. Maximum strength is defined as the capacity to produce force or torque with a maximum voluntary muscle contraction.(1,2) These definitions include some key words that must be explained. A voluntary muscle contraction is "voluntary." When a person&apos;s physical strength is measured, only the effort the person willingly puts forth at the time is measured. Thus, when we test a person&apos;s "maximum strength," we are not measuring his or her actual maximum, but some lesser value representing what he or she is comfortable expressing at the time with the existing equipment and environmental conditions. Interestingly, when researchers startled persons being tested (e.g., by setting off a starter&apos;s pistol behind them), they have found significant increases in measured strength.(3) It has been hypothesized that the lower strength displayed during normal testing provides a margin of safety against overloading and damaging muscle tissue. The test equipment and the tested person&apos;s familiarity with the process also influence the "voluntary" strength output. The interface between the tested person and the test equipment is particularly important. A poorly designed interface induces localized tissue pressures that vary from uncomfortable to painful. In this situation, testers are measuring voluntary discomfort tolerance - not strength. It is important for strength researchers to keep the "voluntary" nature of their data in mind when they are designing their equipment and protocols.

Jan 1, 1998

By T. T. Campbell

This investigation was undertaken by the Bureau of Mines to determine if high-purity ductile molybdenum of uniform quality can be prepared by bomb reduction techniques. Molybdenum trioxide (Mo03) and mixtures of molybdenum dioxide (Mo02) and trioxide were reduced by magnesium in closed steel bomb reactors. Very high pressures in excess of 5,000 p.s.i. developed during magnesium reductions of Mo03. The addition of calcium oxide to the bomb charges caused a significant reduction in pressure. Reaction efficiencies higher than 95 percent were obtained during magnesium reductions of either Mo03 or mixtures of Mo02 and Mo03, but high pressures were encountered when the charges contained from 30 to 60 percent Mo02. Reaction efficiencies were usually low (less than 80 percent) when the bomb charges contained more than 40 percent Mo02. The charges with the best composition considering operating pressure, yield, and purity contained from 10 to 30 percent Mo02. The addition of small amounts of carbon to the reaction charges was helpful because some deoxidation occurred during the reduction and also during subsequent arc-melting of the regulus metal. The purity of the bomb-reduced, arc-cast molybdenum metal ranged from 99.2 to 99.8 percent and in some instances the metal contained as little as 5 parts per million oxygen.

Jan 1, 1962

By H. E. Powell

A laboratory investigation was conducted by the Bureau of Mines to study the magnetic characteristics and to measure the magnetic susceptibility of the mineral siderite. All susceptibility measurements were made by the method of Gouy on powdered samples and at room temperature. Specific susceptibilities of samples from 15 different locations, domestic and foreign, were determined. Values ranged from 66 to 103 (10-6) cgs electromagnetic units. The relation of susceptibility to mineral composition is discussed in this report. The specific susceptibilities of 76 minerals are tabulated in an appendix.

Jan 1, 1963