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By John R. Parker

Work places of an underground coal mine are required (30 CFR 1719) to be illuminated while self-propelled equipment is used. Permissible machine mounted systems have been developed and applied satisfactorily to many mining operations. However, some low seam and thin seam equipment has been difficult to illuminate because reliable, direct current systems and compact, low output, low glare luminaires were not available. This program resulted in the design and prototype construction of compact, low glare luminaires and AC and DC power systems, particularly suited to resolving illumination problems on low and thin seam mining equipment. Design objectives were based on enhancing the prospects for thin seam illumination solutions through definition of a product which could challenge markets enjoyed by higher glare luminaires and through reduction of technical risks associated with any new product development as well as the MSHA certification process.

Jan 1, 1982

By M. E. Volin

The Buckeye manganese deposits are in Stanislaus County, Calif., about 33 miles south of Tracy. From 1917 to 1919 the deposits produced 13,370 tons of ore reported to average 46 percent manganese and 14 percent silica. The deposits are confined to two areas of' development, known as the north mine workings and the south mine workings, about 700 feet apart horizontally. Mineralization occurs chiefly as rhodochrosite and psilomelane interbedded in cherts of the Franciscan formation. As a part of the Bureau of Mines program of investigation and development of domestic mineral deposits, a development project was started November 25, 1940, and completed June 27, 1941. The Federal Geological Survey cooperated by mapping the topography and geology and logging the drill cores. The program included road and. trail building, trenching, underground excavation, diamond drilling, and sampling. The following pages mention the location, brief the history, and note the physical .features of' the district. Mine workings are sketched, the deposit is described, and the plan of the project is noted. The work performed by the Bureau of Mines is explained in the concluding pages with a summary of the drill-hole logs.

Jan 1, 1949

By H. R. Babitzke

The purpose of this investigation was to evaluate the potential of columbium-hafnium alloys as structural materials for use at elevated temperatures. The work described in this report was conducted to determine the properties of columbium-hafnium alloys and to select the more promising ones for further improvement. Properties determined in this report were machinability, hardness, workability, tensile strength, and oxidation resistance. Ten ingots, ranging from 100 percent columbium to 70 atomic-percent hafnium, were prepared and subjected to tests. The test results showed that the alloys with 33 and 50 atomic-percent hafnium were superior in workability, strength, and oxidation resistance. For the alloy series tested, the strength and hardness values increased with the increasing hafnium content. Maximum values were reached with 50 atomic-percent hafnium. The oxidation resistance was poorest at the 1 atomic-percent hafnium level but improved with increasing hafnium content through 70 atomic-percent. Eight of the ten ingots were fabricable at room temperature. The two remaining ingots, those with 5 and 10 atomic-percent hafnium, required hot-working.

Jan 1, 1962

By Dale W. Richardson

Ductile hafnium was not obtained consistently by the conventional Kroll process. The bimetal reduction modification produced a more ductile hafnium by lowering the impurities, especially oxygen, in the sponge metal. Hafnium oxide was chlorinated in the presence of carbon to form anhydrous hafnium tetrachloride, which was reduced by sodium and magnesium in an inert atmosphere to produce sponge hafnium metal. After vacuum distillation to remove the byproducts, the sponge was arc-melted into ingot and rolled into strip. Metallic impurities were decreased by evaporating the hafnium tetrachloride from a fused salt. An excessive amount (over 1,200 parts per million (p.p.m.)) of aluminum was contained in some of the hafnium oxide, much of which remained as aluminum chloride in the hafnium tetrachloride during chlorination. Evaporation of the hafnium tetrachloride from a fused NaCI-KCI mixture during the Mg-Na reduction greatly lowered its aluminum content, as most of the aluminum and some of the other metallic impurities were retained by the fused salt.

Jan 1, 1961

By John J. Sammarco

Illumination plays a critical role in an underground miner?s safety because miners depend most heavily on visual cues to recognize hazards. Mobile mining machinery, located in the miner?s peripheral field-of-view (±10° to about ±60° off-axis), may pose potential pinning and striking hazards. The main objective of this research was to determine if there were peripheral visual performance improvements for the detection of moving objects when using cool-white light-emitting diode (LED) cap lamps as compared to incandescent (INC) light bulbs commonly used in miner cap lamps. The cap lamp variable of interest is the spectral power distribution (SPD); the illuminances were normalized by a diffusion filter. The second objective was to determine if age is a factor for peripheral visual performance. This is important because the workforce is aging ? the average miner age is about 43 years old. Thirty subjects participated in the study; ten subjects each in the age groups of younger (18 to 25 years), middle (40 to 50 years), and older (50+ years). Visual performance was quantified by the subjects? speed and accuracy of response to detect the rotation of high-contrast (white) circular targets located 3.83 meters (m) away at -20°, 40°, and 50° off-axis. The speed of detection and the number of missed target rotations (accuracy) were measured. The prototype LED cap lamp results were best with a 11% to 15% improvement compared to the INC and LED cap lamps respectively. Age does appear to be a significant factor. For the middle and older age groups?, target movement detection time increased 75% and 60% and the number of missed targets increased 500% and 450% respectively in comparison to the youngest age group. The results also suggest that target location is a significant factor. The subjects? target movement detection time for the 40° and 50° target movements increased 16% and 69% respectively as compared to the -20° target.

Jan 1, 2008

By Robert J. Brennan, Edward R. Navrocky, John W. Buch

In an effort to establish a highly productive mechanized mining system for anthracite beds pitching between 10 ° and 20 ° , for which conventional mobile equipment is not adaptable , the Bureau carried out an experiment in longwall mining using an Anderton- type drum cutter loader and friction - type yielding steel roof supports . The roof- support system proved to be inadequate for breaking the overhanging roof at the break line supports , with the result that the roof broke over the solid coal . The accompanying subsidence destroyed the continuity of the roof in the work area , and the project was discontinued .

Jan 1, 1964

By Michael A. Anuta

This report describes the potential for utilization of satellite observations for remote sensing of mine waste disposal areas. Four study sites consisting of metal and nonmetal mining areas in different climatic and physiographic regions of contigous United States were used in this investigation. The mine waste disposal sites consisted of mining of phosphates in Florida, copper in Arizona, silver in Idaho, and coal in West Virginia. Landsat satellite multispectral scanner observations were used together with aerial photographs, ground surveys, U.S. Geological Survey maps, and other ancillary information. Landsat digital data were categorized using automated supervised classification algorithms and an image analysis system. Detailed description of automated classification techniques employed and the accuracy attained is provided together with the results of manual interpretations. The inventory of areas distrubed for phosphate mining and a change detection investigation for-Polk County Florida were also undertaken during this study.

Jan 1, 1982

By Robert S. Sanford, Harold C. Pierce

"At one time the Alaskan Eskimo lived in many small settlements scattered along the Arctic coast. These settlements extended as far south as Bristol Bay and several miles inland on the large rivers. When the white man established trading posts, schools, hospitals, and missions, these people gradually congregated around them in a few large villages. The natural fuel supply near many of the large villages along the Arctic coast became exhausted as a result of the abnormally large influx of people from small outlying settlements.The population of Barrow, Alaska, according to the 1940 census, is 363 persons, but since that time it has increased considerably, and later estimates place the present population between 400 and 500 persons. With the exception of 25 white persons, the entire population is comprised of Eskimos.The government maintains a school, hospital, radio station, and weather station at Barrow. In addition to the government, installations, there is a church, a privately owned trading post, and cooperative store owned by the Eskimos.For many years the Barrow Eskimos depended on driftwood and petroleum residue from Cape Simpson for their fuel supply. This fuel provided not only warmth for the Eskimo during the long cold winters but also heat for melting ice, the only source of 'water during .the winter. In recent years the sources of petroleum residue and driftwood have not been adequate to meet the demands for fuel During the winter of 1942-43 and again in 1943-44, Barrow experienced an acute shortage of fuel.The fuel problem at Barrow was brought to the attention of Governor Ernest E. Gruening, who was instrumental in getting a Bureau of Mines engineer4/ to investigate reported coal occurrences in the vicinity. Coal deposits along the Meade River and at Peard Bay were examined during the spring and fall of 1943. The Alaska Native Service shipped in mining equipment in September 1943 and commenced stripping an open-pit mine on the Meade River in June 1944. In conjunction with this work, an engineer5/ of the Bureau explored by churn drilling to determine the tonnage of- coal in the vicinity of the mine. In addition to this work, the Bureau of mines examined coal deposits in Peard Bay area and along the Kuk River south of Wainwright."

Nov 1, 1924

By R. S. Dean

"INTRODUCTION The idea of direct steel is by no means new. Although the work of Bessemer and Siemens provided simple and effective moans for converting pig iron into steel and established the ""blast-furnace route"" as the almost universal method of producing steel, metallurgists have not ceased to dream of direct steel. By direct steel is meant any process by which iron oxide in ore is reduced to Iron of the same or greater purity than the final steel or wrought iron. That is, carbon or alloying elements would be added as needed, not reduced in unwanted quantities into the iron and then removed more or completely by refining (Bessemer or open hearth) only to be readded in desired quantities.In general, direct-steel processes are ""sponge-iron"" processes, because reducing iron oxide without simultaneously alloying the iron with carbon, phcophorus, sulfur, and silicon present in ore and fuel succeeds only if the temperature is below the melting point of the iron. Such solid iron formed by reduction of iron oxide at relatively low temperature is sponge iron, which is butlery and porous. When the reduction proceeds at the higher temperature at which the particles of metal can weld together or finally even melt to yield pellets or balls that do not have the porosity and low-density characteristic of sponge iron, the product might preferably be called simply ""direct iron."""

Jan 1, 1945

By G. L. Oldright

The data in this paper were collected at the Trail smelter of the Consolidated Mining & Smelting Co. of Canada, Limited, through the courtesy of S. G. Blaylock, vice president and general manager; James Buchanan, smelter superintendent; George Murray, assistant smelter superintendent; and the staff members given in Paper XI, Report of Investigations 3243. INTRODUCTION This paper is the thirteenth of the series on Smelting in the Lead Blast Furnace, and the third of the series on Handling Zinciferous Charges. Tyro other papers have been written on the Rate of Descent of the Stock Column, and Formation of Accretions. These are Reports of Investigations 2963 and 3094, for the Tooele plant and the Bunker Hill plant, respectively.

Jan 1, 1934

By Joseph T. Singewald

The term "titaniferous magnetite" is used to designate those magnetic ores of iron that carry more than 2 or 3 per cent of titanium. Large and easily workable deposits of these ores occur in different parts of the world, and have attracted attention for many years. Under present furnace practice, however, the smelting of these ores is both difficult and expensive, and for that reason they are not accepted by furnaces, so that the deposits are practically worthless. The problem of finding a feasible method of utilizing these ores has naturally been attractive, and numerous attempts have been made to solve it. Experiments to that end embrace two lines of investigation. The one that has been the more frequently tried is the elimination of the titanium from the ores, so as to make possible their smelting in the usual way. The other is the devising of a method of smelting by which titaniferous ores may be reduced as economically as are non-titaniferous ores. The former method involves a physical process, the latter a chemical process.

Jan 1, 1913

By Fieldner. A. C.

"In preparing this paper, an attempt was made to obtain results of plant-scale carbonization tests on washed and unwashed coal tram to same mine. A letter. in which the following questions were asked, was sent to some 50 coke-oven superintendents and others who might be interested:“What is the influence of washing coal on:(1) The chemical and physical properties of coke, as for example, the size, the amount of breeze, the fracture, strength, cell-structure, etc.(2) The quantity and quality of gas and by-products.(3) The capacity of the ovens.(4) The composition of the coal..""Your general opinion, as well as any specific data or results of testa, on this important subject will be greatly appreciated.""Of the 45 replies received, 24 stated that they had never used washed coal; 11 had used washed coal but had no comparative data on similar coals washed and unwashed; 7 answered some of the questions based on their general experience; and 3 gave some test data on Pittsburgh bed coal from western Pennsylvania. In none of the three tests did the washed coal come from the same mine as the unwashed. The washed coals in the three tests were from the same washery - one of modern construction in which the operations are under careful technical control in order to give a uniform product containing a minimum of surface moisture. The unwashed coals which were previously used in these plants were from different nearby mines in the same coal bed, and were supplied by the same company. Obviously, no sweeping or finale conclusions can be drawn from these few tests on coal from a single washery. Therefore, the writer vas obliged to consult the literature, coal-carbonization and coal-washing engineers, and other authorities to supplement the fragmentary information gleaned from the questionnaires in order to present a picture of chat gas engineers may expect from the use of washed coal in a carbonizing plant."

May 1, 1930

By H. C. Miller

For nearly a score of years the American petroleum industry has faced the problem of maintaining its economic structure while oil -producing potentialities greatly exceeded the increasing market demand for oil and its products . However , the combination of maximum civilian demand with rising defense requirements caused an all - time peak in crudeoil production in the latter half of 1941 , with a daily production (as estimated by the Bureau of Mines ) of 4,139,000 barrels in December - an increase of 16 percent over the daily production of 3,573,000 barrels in December 1940. In the event of a long war , a continuing , steady, and adequate supply of petroleum and its products for military and required civilian needs is essential, and the efficiency of recovery of oil from natural underground reservoirs will have to be maximum. Whereas it may not be possible to increase production in some fields , the output from others may have to be drawn at a much faster rate than formerly . More than 10 years ' experience in operating oil fields under proration control has demonstrated to petroleum engineers that some of the efficiency of recovery of oil from reservoir sands and rocks is sacrificed if the oil and gas are withdrawn at too . rapid a rate . As petroleum is an irreplaceable natural resource for which suitable substitutes probably will not be available in desired quantities for many years , any producing method that jeopardizes the quantity of oil that may be recovered from underground reservoirs must be considered at this time of declared war against aggressor nations as conflicting with the best interests of national defense . At best, the efficient recovery of oil is a complex problem . It involves not only a knowledge and application of the fundamentals of fluid flow through porous mediums, but the sources of energy responsible for the movement of oil and gas through reservoir sands and porous rocks to wells must be known to determine the best practices for extracting these hydrocarbons . Reservoir energy is of two kinds - (1 ) water under hydrostatic head underlying the oil in the extraneous parts of the reservoir system and ( 2 ) natural gas under pressure as "free " gas in the reservoir or in solution in the oil . Inasmuch as the efficiency of oil recovery depends largely on the manner in which reservoir energy is used to move oil through reservoir sands and porous rocks to wells , optimum practices for withdrawing the oil cannot be determined until it has been established that the oil in the reservoirs is being forced to wells by an internal gas expansion, by a natural water drive , or by a combination of gas expansion and water drive . There is a fundamental difference in the performance characteristics of gas - expansion and water - drive reservoirs . In a strictly gas - expansion reservoir the energy available to move oil and gas through the porous formations to wells results solely from gas pressure , which is maximum when the reservoir is tapped by the first well . Pressures decline as oil and gas are withdrawn ; consequently, the energy available for moving oil and gas through the oil - bearing formations to wells decreases with production . Curtailing the oil - production rate or shutting in gas - expansion reservoirs entirely will not act to replenish energy previously used in the production of oil and gas ; in their operation , therefore , it is especially important not to waste reservoir energy - the production of oil with high gas : oil ratios will be reflected in lower ultimate recoveries of oil .

Apr 1, 1942

By J. W. Lyman

The U.S. Bureau of Mines investigated methods of separating valuable rare-earth materials from Fe in neodymium iron boron (NdFeB) magnet scrap. A selective oxidation treatment of the scrap oxidized the rare-earth portion while leaving elemental Fe. Magnetic and leaching procedures were tried for separating the metallic Fe and rare-earth oxides, but the extremely fine grain size of the oxidized scrap prevented recovery by either technique. The best separation of rare earths from bulk NdFeB magnet scrap was obtained by dissolution with H2S04 followed by precipitation of recyclable rare-earth salts. By precipitating neodymium-alkali sulfate double salts as an intermediate that can be converted to a variety of useful products, many materials-handling and economic disadvantages found with direct precipitation with fluoride or oxalate were avoided. Iron was removed from magnet leach solutions by precipitation as a jarosite, eliminating a major disposal problem. Research was also conducted with contaminated mixed SmCo5 and NdFeB swarf. Using a flotation-leaching technique allows the SmCo5 to concentrate in the froth, while the grinding-medium contaminant sinks and is removed as tailing. The NdFeB is dissolved by H2S04 during the process.

Jan 1, 2010

By R. R. Sayers

Mine operators and managers for a number of years have known that the maintenance of health among the workers has an appreciable financial value, In order to maintain the health, it has been found ne cessery to imow; 1. The health hazards existing in the industry as a whole and the specific hazard in the individual mine. 2. The physical condition of applicants for employment as well as that of the old employees. This can be determined only by systematic physical examination of all applicants and of regular employees at intervals of at least once a year thereafter. 3. All cases of sickness that occur among the workers. No operator or manager, or personnel, medical, or safety organization can control or prevent sickness without knowing where, when, and under what conditions the sickness actually occurs. In order to obtain information as to the hazards of industry, investigations have been and are being made of the effects of the condi- tions both in the field under usual working practices and in the laboratory. In the field several factors are generally present which affect the health. The effect of these factors may be determined by studying each of them separately in the laboratory. However, both the field and the laboratory studies are limited in value in that such studies usually have been made over a comparatively short period. While we have some information as to their immediate effect, we do not know to what extent extreme heat, humidity, the presence of dust or other health hazards are the cause of disability. Mortality statistics are probably the most easily available indices as to the hazards of industry. As an example, a study of such statistics among coal miners of Indiana shows a marked increase in the death rate in 1918.

Mar 1, 1923

By J. C. LaScola

Development of methanometers and anemometers for underground use in coal mines is reviewed. The first semicontinuous recording methanometer was developed in 1961 in West Germany. The Bureau of Mines developed an instrument using; pellesters that was a continuous recording methanometer. Expansion of freon gas created a vacuum which pulled the methane-air mixture through a tube to an electrically heated, catalyst-impregnated pellester where the mixture was burned. The National Coal Board of England developed a continuous recording methanometer based on the principle of the Davy flame safety lamp. A thermo-pile was used to sense the hurt output of the flame. Finally the Bureau of Mines improved its methanometer by eliminating the freon gas and using a diffuser head to a monitor methane-air mixtures. Development of recording anemometers proceeded from the use of a photo¬cell and light source to sense rotation of the Biram-type anemometer blades to the use of a Hall detector to sense, rotation by measurement of electromagnetic pulses.

Jan 1, 1969

By W. W. Adams

In mining coal, the Nation's principal mineral fuel, loss of life has been much lower recently than in earlier years when coal mining contributed so heavily to the industrial-accident death toll in the United States. Particularly notable has been the relatively small number of deaths during the past few years compared with the number that occurred 20 or 30 years ago. Reports received by the United States Bureau of Mines, covering all commercially operated mines that were active during all or any part of the calendar year 1935, showed that accidents during that year had resulted in the loss of 1,242 lives. This death toll, although regrettable, represents a material improvement over the industry's experience during most years prior to 1935, and especially over the industry's worst year, 1907, when 3,242 men were killed. Fewer lives were lost in 1933, when 1,064 men were killed at work, than during any year for which complete figures are available.

Jan 1, 1938

By C. M. McKinney

The Bureau of Mines analyzed 626 crude oils from 546 oilfields in the United States that produced 2,500 BOPD or more during at least 1 of the last 3 years. Included also are crude oil analyses from eight fields that produced less but which were located in areas having few or no fields that produced 2,500 BOPD. The tables show the geographical and geological source, general characteristics. and determined and computed analytical data for each sample. The analyses were made according to the Bureau of Mines routine method and are directly comparable to other previously published analyses.

Jan 1, 1966

By Arthur B. Campbell

This Bureau of Mines report describes a method that utilizes a computer program to evaluate integral Gaussian profiles of atomic concentration versus depth in a solid. The specific use illustrated involves profiling ion- implanted metals using proton-induced X-ray emission (PIXE) analysis and ion sputtering (IS) for sectioning

Jan 1, 1979

By G. L. Oldright

This paper is the thirteenth of the series on Smelting in the Lead Blast furnace, and the third of the series on Handling Zinciferous Charges. Two other papers have been written on the Rate of Descent of the Stock Column, and Formation of Accretions. These are Reports of Investigations 2963 and 3094, for the Tooele plant and the Bunker Hill plant, respectively.

Jan 1, 1934