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To provide accurate navigation and control of continuous mining systems.

Jan 1, 1996

By Fred D. DeVaney

Copper sulphate is a common flotation reagent for blonde ores. Metallic iron also is present in the mill circuit, and a reaction between the iron and the salt would be in accord with well-known chemistry. The abundance of metallic iron in a flotation food may be noted by even perfunctory examination. First of all the mine contributes metallic iron, then the coarse-crushing machines add their share, and finally the fine-grinding medium its portion. If the grinding is with cast-iron balls the amount of metallics is greater than when steel is used. Thus it, is that much more metallic iron is present than would be indicated by noting the ball consumption. An estimate that the total amount of metallics is twice that supplied by the balls and liners might not be far amiss. That copper sulphate plates out on iron in an acid solution is well known, but since flotation is practiced commonly in solutions where acid has not been added this reaction has not been given sufficient thought.

Jan 1, 1929

By Susan M. Moore

According to the Mine Safety and Health Administration (MSHA) injury database, 227 knee injuries were reported in underground coal mining in 2007 [ 1]. Low-seam coal mines are those with extremely low working heights (<42?). Gallagher et. al [2] found that the average cost per knee injury in low-seam coal operations was $13,121.29. Thus, it can be estimated that the financial burden of knee injuries was nearly three million dollars in 2007. Pressure applied to the knee while kneeling and crawling is likely a risk factor. Typically, mine workers utilize kneepads to better distribute the pressures at the knee; however, their ability to reduce the stresses at the knee is unknown. The objective of this study was to determine the pressure applied to the knee during static postures used in low-seam mining while not wearing kneepads and while wearing two kneepads commonly used in the industry (one articulated and one non-articulated).

Jan 1, 2009

By Peter F. Strong, Robert L. Lagace, Alfred G. Emslie

This paper is concerned with the theoretical study of UHF radio communication in coal mines, with particular reference to the rate of loss of signal strength along a tunnel, and from one tunnel to another around a comer. Of prime interest are the nature of the propagation mechanism and the prediction of the radio frequency that propagates with the smallest loss. Our theoretical results are compared with measurements made by Collins Radio Co. This work was conducted as part of the Pittsburgh Mining and Safety Research Center&apos;s investigation of new ways to reach and extend two-way communications to the key individuals that are highly mobile within the sections and haulage ways of coal mines.

Jan 1, 1973

Coal miners, especially roof bolter and continuous miner operators, work in a hazardous underground environment where they are often exposed to poor roof conditions. Nearly 500 rock fall injuries are reported each year, and 99% of them are caused by rocks falling from between the roof bolts. These loose rocks that injure miners are usually just a few inches thick, but on average weigh 280 pounds. NIOSH has found that most rock fall injuries can be prevented by installing roof screen during the bolting cycle. Roof screen is a sheet made of steel wires in a grid pattern. When screen is bolted up against the mine roof, it provides far more coverage than any common surface control used in the mines today. Because more mine roof is covered, there is less chance that a rock will fall and injure a miner. The facts about roof screen are shown in the new NIOSH video entitled “Make It Safer With Roof Screen.” Using extensive underground footage, the 7-minute video shows how well screen keeps loose rock from falling in difficult roof conditions. Techniques for installing screen from both outside-controlled and walk-thru roof bolting machines are shown. The video also provides safe handling tips, best practices, and information about machine technology that can greatly improve material handling. Throughout the video, a coal mine safety manager and a shift foreman talk about the tremendous difference that roof screen has made at their mines. An instructional booklet supplements the video with additional information. It presents compelling data from mines that have practically eliminated rock fall injuries with a roof screening program. Other sections of the booklet discuss in greater detail roof screen installation, tips for manual screen handling, a material handling system for roof screen, and use of the personal bolter screen, which can be easily handled by one person. Screen specification and custom ordering are described, including the sizes of screen, grid sizes, reinforcing (indicator) wires, edge cut options, and screen strength. A list of additional sources of information is also provided. Nearly every mine eventually encounters poor roof. Screen is one of the most powerful control techniques available. This new video will help make mine managers aware of screen, and it can help them in developing a roof screen installation program. It also serves as an information source and teaching tool for safety managers and trainers. The video can easily be integrated into new miner training programs or annual refresher training.

Mar 1, 2005

By Ralph H. Espach

In the spring of 1943, when it was evident that the Tensleep sandstone in the Elk Basin field, Wyoming and Montana, held a large reserve of petroleum, Bureau of Mines engineers obtained samples of oil from the bottom of nine wells and analyzed them for such physical characteristics as the volumes of gas in solution, saturation pressures or bubble points, shrinkage in volume caused by the release of gas from solution, expansion of the oil with decrease in pressure, and other related properties. The composition of the gas in solution in the oil was studied. The pressures and temperatures existing in the reservoir and the productivity characteristics of the oil wells were determined. The data obtained indicate that the oil in the Tensleep reservoir of the Elk Basin field has unusually varying physical characteristics, such as a saturation pressure of 1,250 pounds per square inch absolute and 490 cubic feet of gas in solution in a barrel of oil at the crest of the structure, and a saturation pressure of 530 pounds per square inch absolute and 134 cubic feet of gas in solution in a barrel of oil low on the flanks. The hydrogen sulfide content of the 6a r; in solution in the oil varies from 18 percent for oil on the crest to 5 percent for oil low on the flanks of the structure. Of even greater significance is the fact that these and other variable characteristics of the reservoir oil are related to the position of oil in the structure. Many geologists and petroleum engineers have considered all the oil in a petroleum reservoir to have uniform physical characteristics and that equilibrium conditions prevailed in all underground accumulations of oil and gas. That such is not always so is borne out by the results of the study made by the writers.

Jan 1, 1951

By M. Copeland

Phase relations of gadolinium alloyed, up to 40 weight-percent (wt pct), with AISI 304-type stainless steel were established. Body-and face-centered cubic iron-rich solid solution phases and several intermetallic gadolinium-containing compounds of variable composition that approximated the formulas Fe9Gd, Ni7Gd2, Ni3Gd, Fe2Gd, NiGd, and NiGd3 were identified. The intermetallic phases Fe9Gd and Ni7Gd2 were noted to melt at about 1,080° C at about 0 to 2 wt pct gadolinium. The melting temperature of Fe9Gd increased with increas-ing gadolinium content to a plateau at about 1,230°C and 30 wt pct gadolinium, and the melting point of Ni7Gd2 decreased to a plateau at 900° C and 30 wt pct gadolinium where Ni3Gd, NiGd, and Fe2Gd coexist. Body-centered cubic iron solid solution was stable from 1 to 2 wt pct gadolinium to higher contents, 30 wt pct gadolinium or possibly more, and face-centered cubic iron up to 12 wt pct gadolinium below 1,200° C. The stability of these phases above 1,200° C was not resolved except for the mel points. A limited number of fabrication variables as well as mechanical and corrosion properties of alloys containing up to 5 wt pct gadolinium were studied. Equilibrating and forming operations were best conducted at about 940° to 1,080° C. Some variability in the yield and tensile strengths of alloys was noted; however, there was a continual decrease in ductility and impact resistance with increasing gadolinium contents. The resistance of gadolinium alloys to corrosion in water at 354° C was about the same as stainless steel.

Jan 1, 1965

By William L. Crentz

Early in the nineteenth century, coal from Clearfield County entered the eastern commercial market. Ashley reports that coal was moved down the Susquehanna River by ark from Clearfield to Columbia, a distance of 260 miles, as early as 18o4. Around 1850, the famous Moshannon or Lower Freeport bed was discovered. Several years later the Moshannon Basin was developed extensively, and the coal from this area soon acquired an enviable reputation as a high-quality industrial fuel. Today much of the original Moshannon Basin coal is worked out, and the Lower Kittanning bed has replaced the Lower Freeport bed as the principal source of production in southeast Clearfield County. With depletion of the thick underground deposits, the importance &apos;of Clearfield County as a coal Producer would have diminished rapidly, if it had not been for strip mining the thinner beds. About 60 percent of the coal produced in the county is strip-mined, and the trend toward this mining method is expected to continue as the older underground operations are exhausted. Many strip mines are working in beds that are too thin to be recovered economically by any other method.

Jan 1, 1952

By David Schlain

"IntroductionThe purpose of this investigation was to study the characteristics of the high-acid electrolytic manganese cell with the idea of fitting it into one of the flow sheets being worked out by the Metallurgical Division of the Bureau of Mines for the recovery of manganese from low-grade domestic ores.In construction, the high-acid cell 3/ differs from the low-acid type in that the cathode and anode compartments are separated by a diaphragm of relatively low porosity, such as alundum. This is necessary because in the high-acid cell the two electrolytes are circulated separately. The anolyte is 15 to 30 percent H2SO4. The catholyte consists of a solution of ammonium sulfate and manganese sulfate with a OH of 4 to 3. The only mixing of electrolytes is that resulting from flow through the diaphragms. In the low-acid cell the two electrolytes are not circulated separately and do not differ so widely in hydrogen-ion concentration. Hence, the canvas diaphragm is sufficient.During operation of the cell, manganese is deposited on the cathode, and sulfuric acid is produced in the anode compartments. Various other reactions take place in the cell. There is considerable decomposition of water; hydrogen is evolved at the cathode, and oxygen is liberated at the anode. When lead anodes are used, some hydrated oxides of manganese are formed at the anodes. The quantity of oxides formed is not as great as it is in the low-acid cell, because fewer Mn++ reach the vicinity of the anodes."

Jul 1, 1942

By E. W. Newman

The Bureau of Mines, in cooperation with the U. S. Geological Survey, developed the property of the Tungsten Metals Corp. by surface trenching and diamond drilling from November 1940 to June 1941 and from August 1943 to December 1943. The purpose of the work was to determine possible reserves of tungsten in the downward extension and lateral eastern extension of three major tungsten-bearing quartz veins. The property is 50 miles south of Ely, White Pine County, Nev., in the Minerva Mining District. Tungsten ore was discovered in the district in 1915, and mining started in 1916. The tungsten ore bodies occur as shoots in quartz veins that occur along faults in limestone. With the exception of a small-scale leasing operation in 1932, the property was idle from 1919 until 1936, when Tungsten Metals Corp. was organized to acquire the mines. Production ceased in May 1945, and the mines were idle until leased in 1947. Development by the Bureau of Mines during 1940 and 1941 consisted of surface trenching, sampling, and diamond drilling 37 holes for a total of 6,959 feet. Subsequent drilling of eight holes, totaling 3,067 feet, in 1943 disclosed additional reserves. This report sets forth in considerable detail the exploration work completed by the Bureau and briefly describes the mining and milling methods employed. Diamond-drill halo logs and sample analyses are shown graphically in the illustrations that accompany the report.

Jan 1, 1950

"While control of dust-related diseases, the objective of the Generic Mineral Technology Center for Respirable Dust, is of prime importance from the human standpoint it is also essential to the economic well-being of the mining industry (FIGURE 23). Although significant progress has been made, the problem continues to be a major concern to the mining community. An increasing global demand for coal and other minerals means that production and the number of miners employed is on the rise. Therefore, the importance of this research to the mining industry cannot be overemphasized.The five areas of dust research are 1) control of dust generation, 2) dilution, dispersion and collection of dust in mine airways, 3) characterization of dust particles, 4) interaction of dust and lungs, 5) relationship of mine environment, geology, and seam characteristics to dust generation and mobility. Some experimental projects where the research is conducted almost exclusively in the laboratory may still rely on industry for imput. No industrial resources are necessary to the research of the non-experimental projects, for example computer modeling .The remaining research is classified as experimental and these projects do require interaction with industry in varying degrees. Periodic trips to mining sites in Western Pennsylvania, Southern Ohio, and West Virginia are necessary to record measurements or collect samples. Or companies may provide needed samples or equipment to the university for use in the laboratory. On several projects interaction is limited to advice or information supplied to the researcher by industry personnel."

Aug 31, 1989

By Mark W. Ryan

The U.S. Bureau of Mines conducted a study to determine if commercially available automatic sprinklers could withstand the high static pressures in deep underground coal mines without leaking and if exposure to the mine environment affected their leak pressures. New sprinklers and sprinklers exposed to the mine environment were subjected to increasing pressures until leakage occurred. The average leak pressures of the new sprinklers ranged from 640 to 2,300 psig and were significantly different for sprinklers from different manufacturers and for different types of sprinklers. Generally, standard-response sprinklers withstood higher pressures than fast-response sprinklers. The results indicated that most commercially available sprinklers would withstand the high static pressures in deep underground coal mines; however, they would not provide the same reliability and safety factor as sprinklers used aboveground at or below their rated pressure of 175 psig. The average leak pressures of the sprinklers exposed to the mine environment ranged from 740 to 1,180 psig. The mine environment affected the ability of 66% of the sprinklers to withstand high static pressures. New sprinklers were also evaluated at pressures of at least 500 psig for 30 days to determine their ability to withstand long-term exposure to high static pressures; no leakage was observed.

Jan 1, 2010

By D. Montagna

This Bureau of Mines report describes a salt-free, fluxless method for reclaiming metallic aluminum from aluminum dross. The dross is smelted under argon, nitrogen, or carbon dioxide, instead of a salt flux, in an externally heated pot furnace. Aluminum recovery, using argon, is equal to recoveries reported from commercial smelters that process dross in rotary-type furnaces This salt-free method could offer a reduction in air pollution, lower energy requirements by elimination of salts, and the production of up to 60 percent less solid waste for disposal than the salt method.

Jan 1, 1978

By T. J. Ballard

The Union Copper mine is in the Gold Hill district; Rowan and Cabarrus Counties, N. C. The mine was discovered in 1799 and first worked as a gold mine; but copper was encountered at depth, and the property became an important producer of copper. It is estimated that the mine produced 5,000,000 pounds of copper before operations were discontinued in 1907. As part of the strategic minerals program, the Bureau of Mines conducted a development project on the property from July 1943 to November 1943. Eight diamond-drill holes totaling 2,500 linear feet were drilled to delineate the ore body. Analyses 205 core samples were made. Tabulations of sample analyses and drill-hole logs are presented in this report.

Jan 1, 1948

By James E. Hill

TECHNOLOGY is best nurtured by a sympathetic climate that is a composite of many factors. Necessity is a highly motivating factor as illustrated by the abnormal surge of technologic development curing wartime. Other factors include appropriate timing, economic pressures, available personnel, and in some instances, legislative action. Problems of recent concern to mining technology have been the quality and quantity of available technical personnel and the possibilities of restrictive legislation. The quality and quantity of technically trained personnel may be inadequate to meet the rapidly increasing complexity of modern technology coupled with the growing demand for qualified personnel. The question of appropriate training was a subject for debate.2 The curriculum and methods of teaching have changed. Questions have been raised on the relationship of scientist and engineer, interdisciplinary versus specialized curriculum, undergraduate versus graduate training, and the place of the smaller schools versus the large university-research complexes that have developed at some universities. Various aspects of the subject of engineering education for the mining industry were discussed at the meeting on Mining and Mineral Engineering Manpower at the Michigan College of Mining and Technology, November 18-19, 1963. Meanwhile, the trend toward interdisciplinary training gathers momentum as illustrated by the establishment of the School of Engineering Science at Johns Hopkins, the Schools of Engineering and Applied Science at Columbia, Princeton, and Yale, the Division of Engineering and Applied Physics at Harvard and, more recently, the School of Engineering Science at Florida State University which cuts across the conventional areas of civil, mechanical, electrical, and chemical engineering.

Jan 1, 1964

By H. S. Chiang, Zhao. Y. F., G. C. Sun, S. S. Peng

"Chiang; H. S. West Virginia UniversityPeng, S. S. West Virginia UniversitySun, G. C. West Virginia UniversityZhao, Y. F.West Virginia UniversityDust sampling was performed in two longwall faces working in two separate seams. Instantaneous dust samples were measured by RAH's. for various locations In the longwall faces. Preliminary analysis of the data shows that in addition to the shearer's haulage speed, there are four major factors that influence the airborne dust distribution in longwall face areas: locations with respect to the position of the shearer's cutting, hardness of the materials, characteristics of water spray, and roof conditions. This paper presents the effects of those four parameters in detail.INTRODUCTIONA research project was initiated in September 1983 to measure and construct .a dust distribution map for the longwall face. During the first year, airborne dust samplings were performed in two longwall panels located in northern and southern West Virginia and working in the Pittsburgh and Eagle Seams, respectively. The physical parameters and equipment employed for both panels are 1 isled in Table 1. Figure 1 shows the detailed characteristics of the coal seams. Notice in both panels floor cutting was involved either to gain sufficient mining height or to reduce the adverse effects associated with a soft floor.The purpose of the research is to define the dust distribution at any instance in the longwall face area so that proper working positions can be determined and/or effective dust control techniques can be developed.This paper presents the partial results obtained during the first year."

Jan 1, 1988

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 R. Marshall

Electrical trailing cable handling techniques and practices used in metal and non-metal surface mines were investigated by obtaining information through actual visits to the mine properties located in a variety of geological areas and climatic conditions. An analysis was made of all accidents related to cable handling which are cataloged by HSAC* for the period from 1971, through June 1980. Information was also collected from mine operators concerning near accidents and non-reported accidents. The results of this investigation were presented to the U.S. Bureau of Mines in an effort to outline recommended practices for cable handling in surface mines and to recommend additions and/or changes in the present regulations now being enforced by MSHA** field inspectors. These recommendations are also intended to assist the U.S. Bureau of Mines in evaluating the need for assisting the mine operators in the areas of training and distribution of information related to material handling of trailing cable. * Health Safety Analysis Center ** Mine Safety & Health Administration

Jan 1, 1980

By Charles H. Shapiro

[In July, 1924, the Bureau of Mines, through its Petroleum Experiment Station, undertook a field study of methods used in oil-field shops for dressing and tempering fishtail bits. The purpose of this work was to suggest chances that would be helpful to the bit-dresser in turning out better treated, harder, and tougher bits, and thus cut down the excessive loss of time caused by too frequent changing of bits. It was the intention to eliminate as much as possible the guess work connected with dressing and tempering bits under the method of judging temperature by eye, by developing; practical methods of controlling temperature. If there were some possible means of accurate temperature control, then it would be an easy matter to bring all bits to the proper temperature for maximum hardness rued toughness, thus doing away with the source of most of the trouble experienced in the present method of bit tempering. Shortly after the Bureau of Mines began its study, a chop In the Stroud, Oklahoma, oil field announced method for tempering fishtail bits that Would increase the drilling footage of each bit treated. The method accurately regulates, by the use of a bath of molten salt, the temperature to which a bit is heated before being quenched to produce hardness. There is nothing new in using silt baths for the, heat treatment of steel, but this was the first attempt to introduce it into the oil fields for use in hardening bits, and for this purpose it proved to be admirably adapted. In tempering, by the old system it is not possible to measure the temperature of the heated bit by means of an electrical instrument for that purpose, whereas this is an easy matter with the now method. If heating steel to slightly above the critical point rind quenching suddenly will bring out its best properties, their here is a method of accurately bringing the steel to that point.]

Jan 1, 1925

By E. R. Cole

Bench-scale research at the Bureau of Mines has resulted in the successful development of a combination electrorefining-electrowinning method for recycling all the lead in scrap batteries. The method reduces energy consumption and eliminates toxic emissions, in contrast to present pyrometallurgical smelting, and the lead produced is pure enough for use in maintenance-free batteries. Anodes cast from molten lead scrap were electrorefined in 1-and 2-liter plastic cells using an electrolyte composition of 70 g/l Pb and 90 g/l free H2SiF6 (fluosilicic acid). Both reagent-grade and waste H2SiF6 were used. Cathode starting sheets were made from refined lead. Aloes, and later bone gelatin, and calcium lignin sulfonate addition agents were employed. The sludge remaining after separation of the lead metal was treated in a two-step leaching operation to solubilize the lead for recovery by electrowinning. Conditions for electrowinning were essentially the same as for electro-refining, except that insoluble Pb02-Ti (lead dioxide-coated titanium) anodes were used. The best results for both electrorefining and electrowinning were obtained with a current density of 170 amp/m2 and a cell temperature of 25° to 35° C. Cathode purity ranged from about 99.9 to 99.99+ pct Pb. Maximum energy consumption after 3 days, for electrorefining and electrowinning, was 90 and 700 kwhr per metric ton of refined lead, respectively.

Jan 1, 1981