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By Lee J. Raabe

A specialized loading system for tensile and fatigue testing of wire rope was constructed and installed in the U.S. Bureau of Mine Wire Rope Test Facility in Bruceton, Pennsylvania. The computer-controlled closed-loop servo-hydraulic test system which can apply up to 800,000 pounds of force on the rope while stretching it up to 30 inches will be used in the development and verification of hoist rope retirement criteria for ropes in the 1 to 2 ½ in. diameter range. Characteristics and capabilities of the system are discussed.

Jan 1, 1984

By L. Nahai

Iran's petroleum industry is nearly 50 years old and the oldest in the Near East. According to published figures, Iran ranks third in production and reserves in the Near East. These reserves (including probable reserves) are estimated at 35 billion barrels and constitute about 11 percent of the world's total. Iran is the sixth largest producer of crude petroleum in the world. The 1961 output of more than 430 million barrels was 5 percent of total world out-put for the year. In the same year, Iran ranked fourth among world petroleum exporters, providing 8.4 percent of total world exports.

Jan 1, 1963

By Oliver Bowles

ASBESTOS is a name applied to a group of naturally fibrous minerals. As indicated in a later section devoted to a detailed discussion of the early history of asbestos, the tern may be defined as a. fibrous form of serpentine or amphibole. It does not include fibrous forms of other minerals, such as wollastonite, nemalite (fibrous brucite), or the fibrous forms of calcite or gypsum. A material that has the characteristics of silk or cotton and at the same time will not burn is unique. Because it combines these qualities with other advantageous properties, asbestos has specialized uses for which no substitutes are yet available. Asbestos furnishes a major raw material for a great variety of essential products and their manufacture constitutes a vast industry. The United States leads all countries in the manufacture of asbestos products. The value of such commodities manufactured in 1952 exceeded $332 million. They are not only of vast importance to budding construction and industry but axe absolutely, essential to certain important fields of use, for example, steam packings and friction materials, such as brake-band linings on automobiles.

Jan 1, 1955

By Margaret R. Egan

A series of experiments were undertaken by the Bureau of Mines to determine the emission products of several types of conveyor belting and other combustible materials found in mines. These experiments were conducted under intermediate-scale, simulated mine conditions to determine smoke characteristics and gas concentrations. From these determinations, heat-release rates, particle sizes, obscuration rates, combustion yields, and production constants were calculated. Three types of belts were investigated: chloroprene, also known as neoprene (NP); polyvinyl chloride (PVC); and styrene-butadiene rubber (SBR). The belts were designated as ignitable or self-extinguishing depending on the length of the burning time and the subsequent combustion products. Under these experimental conditions, the SBR belts were the easiest to ignite. The PVC and NP belts tended to self- extinguish within a few minutes after ignition, but were still capable of maintaining a brief flaming period. These conveyor belt combustion results are compared with previous analyses of wood, transformer fluid, and coal fires. Together they form a data base by which findings from future experiments with other mine combustibles can be compared.

Jan 1, 1988

By J. R. Thoenen

In the summer of 1937 the authors began a series of time studies of the various processes employed in' the production of crushed stone. These studies, made at quarries situated in the eastern and southeastern parts of the United States, have not been completed, but to make results available to the industry as early as possible, it was decided to publish summaries of the studies made to January 1, 1939, as a series of progress reports. The first of these dealt with power-shovel loading and was issued as Report of Investigations 3461 in September 1939. The second, issued in September 1939 as Report of Investigations 3467, dealt with quarry haulage. The present report discusses analyses of time studies of primary drilling at the same group of quarries. OBJECT Or STUDY Pressure of business problems frequently requires the entire attention of quarry management, and in consequence internal plant economies often are neglected. Also, operating officials absorbed in their local problems are prone to overlook possible economies that would attract attention immediately were they critically examining another plant. The authors felt that technical studies at a number of plants, made by impartial engineers, might disclose opportunities to reduce costs or improve efficiency in internal plant processes.

Jan 1, 1940

By John P. Hager

A special inlet system has been developed for a TOF mass spectrometer that allows the equilibrated high-temperature vapors from an atmospheric-pressure flow reactor to be leaked into the ion source of the mass spectrometer without undergoing any compositional changes. Using this flow reactor - mass spectrometer system and a modified transpiration system (one that allows for the carrier stream to be equilibrated with two different condensed samples) a series of fundamental vapor transport studies were undertaken. The results of these studies are summarized as follows: 1. The vapor species in equilibrium with condensed copper (I) chloride were determined to be Cu3C13, Cu4C14, and Cu5C15. The gas mixture is fifty percent tetramer near the melting point (703°K), with the percentage of tetramer decreasing with increasing temperature. The following thermodynamic results were obtained.

Jan 1, 1977

By E. R. Cole

Laboratory heats of an 80 percent copper high-leaded tin-bronze alloy, similar to Brass and Bronze Ingot Institute (BBII) alloy 3A, were made with reduced tin content to determine whether an alloy comparable to BBII alloy 3A could be produced using less tin to aid in conserving this strategic metal. The tin content was lowered from 10 percent to 8 percent and 5 percent (nominal values), respectively, and the reduction in tin was offset by either increasing the lead content or adding zinc. Mechanical properties, machinability, and corrosion characteristics of the resultant alloys were investigated, and the mechanical properties were compared with BBII typical values and American Society for Testing Materials (ASTM) minimums for high-leaded tin-bronze alloy. Results indicate that the tin content of this alloy could be reduced approximately 1 percent (difference between the 8.4 percent actual tin composition obtained and the 9.3 percent BBII minimum) without seriously affecting the desired properties. Results also show the tin content could be reduced without significantly increasing the chances of rejects for mechanical property failures, which might result from normal variations in the casting process.

Jan 1, 1972

By Albert L. Toenges

A phase in strip mining of bituminous coal is the overturning of the surface of the land. The ;purpose of this report is to acquaint the operators and others interested in stripping with the work that has been done in certain States to reclaim the surface of land from which the coal has been removed by this method of mining. The preparation of this manuscript follows an extensive study of the subject in the field in the course of which a large number of strip mines were visited. ACKNOWLEDGMENTS The information used in the report was obtained through the courtesy and cooperation of the operators of the mines visited, State officials and educational institutions, and others interested in the subject.

Jan 1, 1939

By Damon C. Gray

This report contains a recommended program of acoustic research to be conducted by the U. S. Bureau of Mines. The program is directed toward the abatement and control of machinery noise in underground coal mining operations. The study conclusions and specific problem areas which led to the definition of the recommended program are also briefly described.

Jan 1, 1971

By Terry McMahon

This Bureau of Mines report describes the rock burst problem and measures being taken for its alleviation in the deep underground mines of the Coeur d?Alene Mining District in northern Idaho. The geologic features that contribute to rock bursting in that area are discussed and briefly compared with similar features in other burst-prone mining districts throughout the world. Early investigations to understand and control rock bursting are reviewed, and the mechanics of bursting are discussed in terms of the seismic events that produce them. Sources of strain energy, rock failure mechanisms, and the conditions necessary for the release of seismic energy are covered in detail. Rock burst research in the Coeur d'Alene District is described. Included are discussions of the microseismic method as both a research tool and as a rock burst monitoring system, rock destress blasting and preconditioning methods for rock burst control, and stoping methods currently being developed to reduce rock burst hazards.

Jan 1, 1988

By William E. Souder

Behavioral accidents are a particular type of accident. They are caused by inappropriate individual behaviors and faulty reactions. Catastrophe theory is a means for mathematically modeling the dynamic processes that underlie behavioral accidents. Based on a comprehensive data base of mining accidents, a computerized catastrophe model has been developed by the Bureau of Mines. This model systematically links individual psychological, group behavioral, and mine environmental variables with other accident causing factors. It answers several longstanding questions about why some normally safe behaving persons may spontaneously engage in unsafe acts that have high risks of serious injury. Field tests with the model indicate that it has three important uses: It can be used as an effective training aid for increasing employee safety consciousness; it can be used as a management laboratory for testing decision alternatives and policies; and it can be used to help design the most effective work teams.

By Kevin Connor

During 1986, the Government continued with efforts to ease the country's almost total reliance on coffee exports for trade revenues by allocating 45% of the Government's budget to commerce and industrial projects. The collapse in coffee prices in 1985 continued to exacerbate the country's growing trade deficit, weakened currency, and dwindling reserves of foreign exchange in 1986. Amoco Burundi Petroleum Corp., a subsidiary of Amoco International Oil Co., continued with plans to drill at least two exploration wells in Lake Tanganyika in 1987. Both offshore and onshore drilling exploration was planned by Amoco Burundi. Any oil or gas finds were expected to have substantial impact on the Burundian economy, as a major portion of the country's trade deficit was directly attributable to petroleum and gas imports.

Jan 1, 1988

By W. F. Wyman, S. F. Ravitz

"INTRODUCTION By far the greater part of the high-grade manganese ore used in the United States is imported from overseas. During the early part of the recent World War importations of manganese ore were seriously threated, and it appeared that it would be necessary to utilize low-grade domestic ores to the fullest possible extent. Among the processes that appeared to offer the best possibilities for beneficating low-grade domestic oxide manganese ores, which ordinarily are net readily amenable concentration by ore-dressing methods, were those involving leaching with sulfur dioxide. The Bureau of Mines therefore investigated the amenability of a large number of such ores to sulfur dioxide leaching.Several sulfur dioxide processes for beneficiating low-grade oxide manganese ores have been proposed. 3/ One of these, based on a patent by Van Arsdale and Maier, 4/ was used recently in a plant constructed to treat 1,000 tons per day of 20-percent manganese ore from the Three Kids deposit near Las Vegas, Nev. 5/ In this process the ore slurry is leached with sulfur dioxide gas, the resulting solution is evaporated to crystallize the manganese sulfate, the crystals are decomposed thermally to produce high-grade manganese oxide and regenerate sulfur dioxide, and the manganese oxide product is nodulized. The Bureau of Mines has recently developed a process 6/ in which a suspension of the ore in calcium dithionate solution is leached with dilute S02 gas, the manganese is recovered from the resulting solution by a simple lime precipitation, and the precipitate is nodulized or sintered to form a high-grade manga¬nese oxide product."

Jun 1, 1947

By G. F. Livingston, F. K. Shelton, J. C. Stahl, R. E. Churchward

"INTRODUCTION An investigation of the metallurgy of cobalt from domestic ores has been in progress since February 1940 and has resulted in the formation of a hydrometallurgleal process for the production of electrolytic cobalt metal. Previous reports of these investigations have been given by F. K. Shelton; 7/ and Ruth E. Churchwrd, F. K. Shelton, and G. Knickerbocker. 8/ Briefly, the process, as applied to ores containing cobalt oxide, consists of leaching with H2SO3 or, preferably, with H2SO3 and H2SO4, to dissolve the cobalt. The cobalt solution passes through one or more purification stages to remove iron and elements of the copper group, and cobalt carbonate is precipitated under carefully controlled pH conditions. The cobalt carbonate is dissolved in on acid electrolyte containing sulfuric acid, boric acid, and sodium fluoride. The electrolyte then proceeds to electrolytic cells where cobalt is plated as a metal and sulfuric acid is regenerated.The present paper contains the results of several investigations signed to give a more complete chemical and engineering understanding of different unit processes involved in the electrowinning of colbat. Some work has been done to broaden the process to include arseniferrous cobalt ores as well as the oxide ores upon which the investigation was initiated. Most of the data presented herein have been obtained since the release of the previous reports; any changes suggested heroin that conflict with recommendations in earlier reports are based on more complete data and usually are preferable."

Nov 1, 1945

By John R. Bartels

This U.S. Bureau of Mines report describes the development, system by system evaluation, and preliminary surface testing of a flywheel-powered shuttle car (FPSC). The use of a self-contained flywheel-power source has the potential to eliminate the numerous safety and routing problems associated with tethered mobile equipment. An alternative to conventional power cable systems was developed consisting of the world's fIrst seven-rotor stacked flywheel system capable of storing 6 kW·h of energy at 16,700 rpm. Numerous interdependent systems were necessary for successful interfacing with a conventional shuttle car. Each of these systems was evaluated and tested individually. Finally, the entire shuttle car was surface tested. The tests indicated that the flywheel energy system can function and operate a shuttle car. The economics of the system and the design of required support systems were not addressed in the project.

Jan 1, 1991

By F. G. Miller, H. C. Miller

Petroleum technologists and progressive operators constantly are striving to increase the percentage of oil that may to recovered from reservoir rocks through wells. The exhaustive studies that have been made of the function of natural as in the production of oil, for example, have aided operators greatly in increasing the quantity of oil recovered from reservoirs. Natural gas dissolved in and otherwise associated under pressure with oil in reservoir rocks, however, is not the only source of energy available for moving oil through sands to wells. In becoming "reservoir—energy conscious" engineers have learned that in many petroleum reservoirs the edgewater flanking the oil accumulation constitutes a potential source of energy capable, through proper control, of increasing oil—recovery efficiencies materially. No longer is the encroachment of water into the oil— and gas—filled tart of the reservoir considered as an evil to be combatted by devious methods but rather a natural consequence, incident to the withdrawal of nil and as from the wells, that may be used advantageously in lengthening the flowing life of wells and increasing the economic recovery of oil and gas.

Mar 1, 1938

By David A. Benjamin

At the request of the U.S. Bureau of Land Management, the U.S. Bureau of Mines studied prospects, claims, and mineralized sites in a 43,053-acre portion of the 51,262-acre Desatoya Mountains Wilderness Study Area (NV-030-l10) in 1985. The study area, located 50 miles east of Fallon, NV, is underlain by alluvial deposits of Quaternary age and volcanic and volcanic-derived sedimentary rock of Tertiary age. No mines or recent exploration activity were identified within the area studied. The Gold Basin area, located 1/2 mile to the south has produced 982 ounces of gold and 10,086 ounces of silver. The Cold Springs area, located 1/2 mile to the west, has recently been explored for gold-silver. Mineralization at these two areas apparently did not extend into the study area, but future mining at these areas would likely impact it.

Jan 1, 1986

By H. S. Benson

This report documents, from concept through field testing, the pan scraper Wheel Slip Monitor. The function of this device is to instantly warn the scraper operator of wheel slip and thus enable him to take immediate corrective action. Knowledgeable pan scraper people recognize that the preponderance of scraper tire damage and wear occurs during useless wheel slip when the scraper operator attempts to increase machine draft beyond what traction will allow. The resultant shortened tire life has become very expensive. The Wheel Slip Monitor reported here provides the means for relieving the scraper operator of attempting to judge wheel slip on tires he cannot see. Direct and intuitively understandable audible and flashing light warnings tell the scraper operator which wheel is slipping and also indicate the relative magnitude of the slip. Beside the Wheel Slip Monitor's patent utility as a real time operator aid, it has unique potential for application to extended term wheel slip history acquisition under field conditions. This information has never been easily available and it promises practical value in pan scraper management.

Jan 1, 1983

By Galen G. Waddell

The Deep Creek zinc and lead mine afforded an excellent example of a relatively small underground mine operation that approached the low mining costs of large, highly mechanized mines. An open stope mining method incorporating sublevel benches and vertical long holes was used (fig. 1). Detailed descriptions are given on the exploration program, stope development, stoping procedures, and pillar removal. Pressure grouting was used to check the inflow of water and thus prolong the life of the mine. Statistics on mining costs and on electric power consumption, haulage from mine to mill, and milling costs are included.

Jan 1, 1963

By Edward A. McClatchie

A methane monitor that complies with 30CFR75.313 has been designed and fabricated using a novel pressure modulated infrared absorption technique. The methane monitor met or exceeded in performance all of its target specifications. The monitor was operated continuously during production mining for the entire duration (45 days) of the in-mine test; no failures occurred during the test. The monitor was regularly checked with calibration gas and no shifts in calibration were found during the in-mine test. Operating principles, performance data and electrical schematics are included in the report.

Jan 1, 1976