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By R. V. Ramani

In this the available information friction factors and leakage report, on characteristics are reviewed and summarized. The use of Penn State Mine Ventilation Simulator (Volumes II and III of the Final Report) to analyze the sensitivity of the ventilation system to the changes in leakage and friction factors is discussed with examples. In simple ventilation systems, the results of changes in leakage and friction factors can be easily solved and explained by the laws of air-flow. In complex systems, with fixed quantity branches and multiple sections, the effect of changes in leakage and friction factors cannot be generalized. This study points out the importance of good input data for obtaining reliable information from computer analyses and demonstrates the application of simulators to analyze the effectiveness of ventilation systems. An extensive bibliography on friction factors, leakage characteristics and ventilation economics is included.

Jan 1, 1977

By Robert S. Warfield

Eight samples of high-volatile bituminous coal, each large enough for a study of its coking properties by the Bureau of Mines, were obtained from a location along the Kukpowruk River, Arctic Northwestern Alaska. Bench scale and pilot plant carbonization studies with several patterns of coal blending were conducted. The data from these tests were compared to data from similar tests on a coking blend used by the Kaiser Steel Corporation at Fontana, Calif. The majority of the samples representing the 20-foot seam was found to have significant coking properties, and produced coke approaching metallurgical quality when blended with selected coking coals. Although oxidation effects were evident in the samples representing upper portions of the seam, it appears that the whole seam could be used.

Jan 1, 1966

By Louis E. Dalverny

U.S. Bureau of Mines research to develop diagnostic methods to locate and evaluate fires in abandoned mines and waste banks and techniques to extinguish such fires was applied to an abandoned 60-acre underground bituminous coal mine (Renton, Allegheny County, PA) to locate and extinguish three separated fire zones. Mine fire diagnostics interpret changes from baseline values in subsurface pressures, temperatures, and mine gas composition under imposed pressure gradients induced by a borehole exhaust fan. The effective gas sampling area surrounding each borehole is greatly enlarged. Sampling iterations, using a "communicating" boreholes set, provide "fire signature" information for locating both heated and cold areas. Time-dependent monitoring differentiates heating and cooling periods resulting from combustion front movement and/or fire extinguishment activities. A water injection with fume exhaustion extinguishment effort involved injecting water through boreholes to quench the heated zones while exhaust fans actively removed heated gases from the mine. The technique was ineffective as implemented, primarily because of inadequate spreading of water from the injection points. The Bureau's diagnostic method determined the fire locations and the effectiveness of the water injection with fume exhaustion extinguishment technique.

Jan 1, 2010

By Charles H. Atkinson, Robert T. Johansen

Tremendous volumes of petroleum ( crude oil and natural gas ) at present cannot be recovered economically . The feasibility of using nuclear explosions for production stimulation therefore has been investigated . Data from underground nuclear tests conducted by the Atomic Energy Commission were reviewed , and the physical effects were evaluated for stimulating petroleum production . Calculations of the effect on ultimate recovery of increasing reservoir temperature with nuclear explosives showed disappointingly small increases . Production increases caused by fracturing of massive low- permeability reservoirs appear technically and economically promising . Petroleum reservoirs that might be converted from submarginal to commercial production are being located and evaluated as to potential reserves and as a location for a field test .

Jan 1, 1964

By Alan G. Mayton

A prototype end-cab shuttle car (SC) design has been developed to improve protection and address ergonomic concerns of the SC operator in low coal mines. The new design features an end cab transversely mounted to the SC and equipped with a closed-circuit video system. The end cab was retrofitted to a low-coal SC and evaluated in surface trials at the U.S. Bureau of Mines. During surface trials, test operators evaluated the end-cab SC relative to visibility; cab features-space, seating, controls, and operator position; tramming-inby, outby, and turning corners; and dumping. Trials were conducted using 12 test subjects; 6 were experienced SC operators. Results of the trials were promising. Of the experienced operators, the only operator with low-coal experience gave the new design the highest rating. Four experienced operators rated the end-cab design "better" to "much better" than a standard center-driven, side-cab SC for visibility when tramming, protection from roof and rib hazards, and no change in seat position with direction of travel. This report discusses research to modify a used 21SC JOY SC, retrofit the SC with the Bureau-developed end-cab, and evaluate the retrofitted end-cab SC in surface trials.

Jan 1, 2010

By Donald W. Ross

"INTRODUCTION Sponge iron has been made commercially since 1912 at a Swedish ceramic plant; and the product, known as Swedish disk—type sagger sponge iron, has an excellent reputation as a superior furnace feed wherever high—grade steels are made. The general procedure for making brickyard sponge iron was described frequently in Swedish technical journals prior to 1932 and at that time consisted in filling clay refractory containers, called saggers, with a super-concentrate of Gellivare magnetite plus the necessary amount of solid reducing agent and desulfurizer and then firing in a Hoffmann ring furnace, as used in the ceramic industry.The early Swedish publications describe two types of brickyard sponge iron: (1) An inferior high-sulfur product obtained by mixing the ore and reducing agent, and (2) a high-grade low-sulfur product in the form of coherent disks 7 to 9 inches in diameter and 1 to 1-1/2 inches thick made by the saggers with alternate layers of solid-fuel reducr and of uniaxed ore."

Sep 1, 1945

By J. B. Zadra

Tungsten, a comparatively new metal, is one of the important strategic war materials. In peacetime, tungsten is widely used as a filament in elec¬tric lamps and electronic tubes and is a vital constituent of some of the most important industrial alloys. High-speed tool steel containing tungsten and stellite alloys containing cobalt, chromium, and tungsten are extremely hard and resistant to corrosion. These alloys and the tungsten carbides are unequaled as cutting tools and in other wear-resistant applications. They play a prominent role in the present era of mass production. Alloys containing tungsten resist oxidation at high temperatures and have been key alloys in the development of modern aircraft. The adaptability of tungsten to new uses is expanding, particularly in the high-temperature range. Domestic production of tungsten has come from a large number of deposits in 17 of the 49 States; but, of the total domestic output from 1900 to 1956, more than 80 percent was produced from mines in North Carolina, California, Colorado, and Nevada. The average tenor of the mined ore was less than 1 percent tungsten trioxide (W03).

Jan 1, 1959

By L. C. IlsLey

The theory and practice followed by the Bureau of Mines in investigating electrical equipment4/ made for service in gassy mines are of particular interest not only to manufacturers but also to those organizations that deal with safety anal inspection at the mines. This publication purposes to discuss the theory upon which tests of equipment in explosive atmospheres are based and to consider inspection and other matters pertaining to investigations made by the Bureau in ascertaining whether a machine merits approval. The material in this report is taken from an earlier bulletin,5/ which is row out of print, and has been revised and brought up to date to make the information again available to manufacturers, inspectors, and others interested in the development of safe equipment.

Jan 1, 1954

By M. W. Von Bernewitz, J. J. Forbes

"In the United States there are hundreds of underground and surface (inside and outside) inclines at coal mines on which trips of cars are continually being run with coal, rock, supplies, and men. The safety of the men and prevention of damage to the slopes depend, excluding the personal element of the hoist-man, on the strength and condition of the wire cable, draw bars, and the couplings, and on the links of chains and pins as well. Within a recent period of four weeks there have been two runaway trips, one on the surface and one underground; it seems desirable to call attention of mechanical engineers and others at coal mines to the need for closer and more frequent inspection of the cable, draw bars, coupling links and pins, derailing devices, wheels, brakes, and other parts of cars or trips on which men are hauled on inclines. This bureau has never published anything on this class of accident heretofore.How frequently runaway trips occur is not known. If no serious injury or fatalit has to be reported to the State authorities, a number of such happenings may occur and not be mentioned outside of the immediate vicinity of the mine.Runaway trips can and do result in considerable loss of life, in injuries, and damage, either at or near the place of the break, or throughout a mine by causing an explosion of gas or coal-dust or both, This report is restricted to a study of the mechanical and physical phases of car trip construction and of the metal of couplings and ropes; derailed trips are not included and may be the subject of another paper. There is no need to mention gas accumulations, coal-dust and rock-dusting, open lights, protected power lines, and permissible equipment, because these have all been well covered in Bureau of Mines publications which have been widely distributed and partly or wholly reprinted by others.Most of the items regarding the runaway trips tabulated have been abstracted from reports made respectively by Clarence Hall, W.O. Snelling, and J. W. Paul; D. Harrington and J. J. Forbes; H. C, Howarth and G. S. McCaa; K. L. Marshall and E. H. Denny; J. J. Forbes, G. W.- Grove, and R. D. Currie; S, P .Howell and K. L. Marshall; and .J. W. Paul, H. D. Mason, and G. E. McElroy, all of the mining and safety divisions; and C. H. Herty, jr., and G. R. Fitterer of the metallurgical section of the Bureau of Mines. W. J. Fene, K. L. Marshall, and S. P. Howell of the safety division, and J. F. Lessig, mechanical engineer, and G. St. J. Perrott, superintendent, Pittsburgh Experiment Station, read the text and offered sugges¬tions. W. J. McGregor, coroner for Allegheny County, and P. F. Nairn, State Mine Inspector of Pennsylvania, contributed valuable information."

Mar 1, 1931

By Leonard Obert

THIS REPORT presents methods and principles useful in designing underground mine openings and pillars in competent rock formations. Two types of formations are considered: (1) Massive formations, in which openings are generally mined with an arched roof, and (2) bedded formations, in which openings are generally mined with a flat roof. Design principles for openings and pillars in massive formations are obtained by considering the maximum tangential stresses developed around single and multiple openings for stress fields of various types. Design principles for openings and pillars in bedded formations are obtained by considering the average stress in pillars and the maximum stresses in roof layers. Experimental procedures for making stress, strain, and in situ physical-property measurements in underground mines to check design calculations are outlined and the results discussed.

Jan 1, 1960

By Nirander M. Safaya

Revegetation success on surface mined lands is dependent upon the nature of the plant growth media. Soil physical and chemical properties dictate the needs for specific reclamation and subsequent management practices. Field experiments were conducted at six coal mine sites in Oliver and Mercer Counties, North Dakota to determine the subsequent effects of a single application of selected amendments on spoil and topsoils over the five year period, 1974-1978. Considerable variations in the physical and chemical properties were found in mine spoils from site to site. The texture of spoils ranged from sandy clay loamy at North Beulah I to loamy at Glenharold, and from sandy loamy at North Beulah 3 and South Beulah sites to loamy sands at the Center site. The pH of the sites ranged from 6.5 at South Beulah to 8.2 at North Beulah 3. In many cases, the pH values of mine spoils were not significantly different from the topsoils. The electrical conductivity (ECe) did not exceed 6 mmhos cm-1 at the test sites even though in other studies much higher values were recorded in the same vicinity. The spoils from Glenharold and North Beulah test sites can be classed as moderately saline, and those from Center and South Beulah as non-saline. The sodium adsorption ratios (SAR) varied from less than 1 to 32, with highest values in the spoils of North Beulah 3 followed by Glenharold; all other sites were nonsodic. Lowest SAR values (less than 1) were found in the topsoiled sites at South Beulah and Center. Spoils of North Beulah 3 test site were highly calcareous, followed by North Beulah 2 and Glenharold. Center mine spoils which were the least calcareous of the test sites, showed the calcium carbonate equivalent three times higher than that of the topsoil. The average calcium concentrations in the spoils of North Beulah 3 and South Beulah test sites were -13 and 14 me 100g -l while at North Beulah 2 and Glenharold test sites 25 and 22 me 100-1-1 were recorded, respectively. The overall magnesium concentrations ranged from an average of 4 to 16 me 100g 1. Sodium concentrations in all sites never exceeded 10 me 100g-1. Phosphorus concentrations on the average at North Beulah 1, North Beulah 2, and Center were 10.2, 4.6, and 22.2 µg g -1 spoil, respectively. Concentrations of potassium ranged from 200 ppm at South Beulah site to more than 375 pp in at the Glenharold site. High concentrations of sulfates (239-2778 µg g-1) seem to contribute to the salinity in these spoils. Chloride concentrations of spoils were low and never exceeded 40 µg g-1 spoil. Based on established critical levels of deficiency for micronutrients in agricultural soils, it seems that none of these were deficient. However, controlled environment experiments did reveal increased plant growth responses when some micronutrients were added to the mine spoils. Treatment effects were highly site specific depending on the nature of the soil/spoil characteristics and, of course, the properties of the various treatments. While slack coal amendment to the spoils at North Beulah 2 site affected significant increases in a large number of variables (both major and trace elements), amendment of the topsoils at the South Beulah test site with leonardite resulted in significant decreases in a number of variables, particularly trace elements. Spoils at Glenharold and North Beulah 3 demonstrated the fewest significant changes due to amendments. Calcium, magnesium, strontium, organic matter and nitrogen were consistently increased from site to site with the addition of lignitic materials. Other spoil/topsoil physical and chemical properties (30 variables) as affected by amendments and time are discussed.

Jan 1, 1982

By Jan C. Still

The Haines-Klukwan-Porcupine subarea of the Juneau Mining District (JMD) is located in the northern portion of the JMD and consists of the land between the Alaska-British Columbia boundary, the Chilkoot Valley, Glacier Bay National Park boundary, and extending south to the Davidson Glacier and the Chilkat Peninsula and Islands (fig A-I). This area was studied as part of the larger JMD study in a cooperative effort between the Alaska Division of Geological and Geophysical Surveys (ADGGS) and the Bureau during 1985 to 1988. Prior to this, during 1984, the ADGGS and the Bureau cooperated in a study of the Porcupine mining area and during 1981 to 1983 conducted separate studies in the area. Field work was conducted by foot, boat, truck, and helicopter. Figure A-I shows the Haines-Klukwan-Porcupine sub-area and shows the areas covered by previous Bureau and ADGGS studies. PHYSIOGRAPHY AND CLIMATE The physiography of the subarea ranges from gentle to rugged. Glaciers formed the major features in the sub-area and left "U" shaped steep walled valleys and rugged mountains. The Chilkat, Chilkoot, Klehini, Tsirku, and Takhin are the major rivers in the subarea. The higher mountains are glacier clad and some valleys still harbor glaciers that reach the valley floors. Lush forests and dense brush predominate up to timberline at about the 2,000-foot elevation. Low point in the subarea is at sea level in the area around Haines while the high point is 7,434 feet at: Mount Henry Clay in the Porcupine mining area.

Jan 1, 2012

By James Westfield

A brief résumé follows of some of the most recent activities of the Division of Coal-Mine Inspection that have had a favorable effect. on health, safety, and injuries at coal mines: 1. There were approximately 8,510 active coal mines in the United States during 1955. In all, 82,389 regular Federal inspections of coal mines have been made since Public Law 49 became effective in May 1941; 9,823 of these inspections were made during 1955. 2. The Bureau of Mines introduced the revised Coal-Mine Accident-Prevention Course for Supervisors in the coal-mining industry on March 1, 1948. Since that date, 19,455 supervisors and those aspiring to official positions have completed such training conducted by personnel of the Division of Coal-Mine Inspection.

Jan 1, 1956

By G. C. Price

This study traces the development of the bucket-wheel excavator, points out the differences in the German- and American-type wheels, and gives the major design criteria and the advantages and disadvantages of bucket-wheel operations. A computer program, written in FORTRAN IV for use with an IBM 360 computer, simulates the operation of the digging components of a bucket-wheel excavator. By supplying certain mining dimensions, soil characteristics, and machine design specifications, this program will print out a time study of the various components of an operation, power calculations for the operation, and production data. This program, when combined with a truck, belt, or rail program, should be helpful in planning a complete mining system In material suitable for a bucket-wheel excavator operation.

Jan 1, 1973

The development of the potential supply analytic system has advanced to the point that quantitative estimates of economically recoverable resources can be made as the final step of the traditional regional mineral resource assessment process. In 1983, the BOM and the ADGGS jointly developed a methodology to quantitatively assess the potential for undiscovered yet economically recoverable minerals within a designated geographic area. This methodology was first applied in the assessment of the undiscovered mineral potential of the Kantishna Hills, Alaska (White et al., 1987). At that time the assessment procedure combined a series of technical judgements regarding the major geologic, engineering and economic factors that influenced the occurrence and exploitation of mineral resources in the Kantishna Hills area. Since then the methodology has been further developed and enhanced, particularly with respect to the engineering and economic analysis components. The resulting Potential Supply Analysis System (PSAS) was recently used to evaluate the economic potential of selected types of undiscovered precious-metal deposits in the Tonopah quadrangle of Nevada (Gunther, et al., 1988) and, with some enhancements, has been used to estimate the' economic value of the undiscovered mineral potential of the WMNRA/SNCA study area. The PSAS has been designed to address five basic questions about the mineral potential of an area: 1) What alternative states of geologic nature are possible in the area of interest (e.g. How many and what types of undiscovered deposits could be present and what might be their grade, tonnage and depth attributes?) ?;

Jan 1, 2011

This report describes the new Bureau of Mines Core Repository System (CORES) and presents the methods for selecting, processing, and storing physical samples and descriptive data for future reference by earth scientists. The system preserves splits of chip samples and longitudinally sliced segments of core. A records retrieval system provides for storage of data on microfilm and magnetic tapes and uses the keysort parameters of location and commodity for the identification of data.

Jan 1, 1978

By Bertrand L. Johnson

Before 1914 , Chile , because of her extensive resources of natural nitrates , practically monopolized the world markets for one of the leading fertilizer materials . Since nitrogen also is an important war material , constituting in fact the principal ingredient in many high-powered explosives , the World War and the widespread insistence upon national self- sufficiency for war materials brought about the development of nitrogen fixation plants in all of the larger countries . The production of by- product ammonia from gas and coke plants was likewise stimulated . As a result , Chile , even after the ocean lanes were reopened , was forced to fight for her lost markets . Since the world capacity to produce is still far in excess of annual consumption , the competition between natural and synthetic supplies has been keen and prices have fallen below pre-war levels . Chile has recently succeeded in unifying her industry , utilizing the most efficient process now in operation, and the Government is a partner in the new company that will take over all of the present producing companies . These developments place Chilean nitrate of soda , in a much more favorable position among the markets of the world . More intense competition will undoubtedly follow and , in order that those interested may become familiar with the fields upon which the nitrogen conflicts of the near future may be waged , the following general summary of the nitrogen industry has been prepared .

Jan 1, 1931

By Mark S. Sanders

The present study was designed to explore the contribution of organizational climate and management practices to the injury experience in underground coal mines. A cross-lagged panel design was used in which miners from 22 mines completed questionnaires assessing 27 organizational climate, structure, and function dimensions on two occasions, The results strongly support the hypothesis that climate and management practice have casual effect on the incidence of disabling injuries.

Jan 1, 1976

By W. M. Weigel

"Sand is one of the most useful and, fortunately, one of the most common mineral commodities. By far the largest proportion of the production is used in construction, including all forms of building, concrete and paving, sand for this purpose is produced in every State in appreciable amounts. Excluding send used for railroad ballast, molding sand stands not in tonnage produced, followed by glass sand.Special sands. In addition to the above, many grades of sands, with special characteristics, are used in industrial processes, and may be classed in a group as ""special sends"". This includes filter sand, sand blast sand, engine sand, abrasive send, fire or furnace send, special flooring sand, roofing sand used as a finish for prepared roofings and pottery placing sand sand blast and filter sand have been discussed in previous reports.Very few send companies depend upon the production of any one of these grades, as their source of revenue. They are generally especially prepared from the bank run of sand by different methods of screening or washing, or may, in some instances, be by-products from the production of ether grades. Many companies not now producing them might be able to supply local demands by a slight addition to their plant. In nearly all cases, they command a better price than the usual grades of building sand.Definitions and Properties.Engine sand, or traction sand, as it is sometimes called, is used to prevent the slipping of the driving wheels of locomotives, or other self-propelled vehicles, on wet or slippery rails. Its greatest use is, of course, for railroad locomotives, but street cars use considerable amounts and mine locomotives require its use. As the send must be very dry when used, most consumers have their can drying equipment, so it is often shipped damp, with its natural water content on what resulting from washing by the producer."

Oct 1, 1924

By E. D. Gardner

Oil shale, a long-considered potential source of motor fuel in the United States, is found over an extensive area in the Green River formation in Colorado, Utah, and Wyoming.4/ Oil has been retorted commercially from shale in Scotland for many years,5/ and work done by the Bureau of Mines and other investigators has shown that it is technically feasible to extract oil from American shales.6/ By refining, the shale oil may be converted into marketable products similar to those manufactured from crude petroleum. The present paper, which was finished in 1936, discusses methods that would be adaptable to mining certain American shales, and the treatment applies specifically to conditions iii the Green River formation on Naval

Jan 1, 1942