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By W. G. Pariseau

A two-dimensional finite element program has been modified and extended to account for some of the rock mechanics complexities associated with single entry development of longwall coal mine panels. Program capability includes arbitrary assignment of element properties without regard to element ordering, anisotropic elastic, plastic and brittle rock properties that may be time dependent (aging), arbitrary mining sequences and provision for the effects of artificial support on the adjacent strata. Failure is according to an extended von Mises criterion that may be linear or quadratic in form; flow rules are obtained from the yield function taken as the plastic potential, but brittle behavior is treated as a discontinuous process of material properties change with deformation. In either case the extent of failure is calculated from the external boundary conditions. Application of the program to essentially two-dimensional problems resulted in lose agreement between calculated displacements and field measurements in the double entry system. Bleeder entries were stable in one locality and not in another. Artificial support had little influence on stability.

Jan 1, 1978

By W. R. K. Wu

Results of linear correlations of two to four variables by the least-squares method are presented. The variables include 63 parameters representing coal composition, coal plasticity, and coke strength. The composition parameters are on chemical analyses; the plasticity parameters, on three plastometer and dilatometer tests and four miscellaneous tests; and the coke-strength parameters, on three ASTM indices. Seventy-two to eighty-four plastic coals were used in the plasticity and carbonization tests, which together form the basis of this report; 43 nonplastic or weakly plastic coals were used in the coal-band studies. Plots of relations between volatile matter, carbon, and oxygen contents of 1,860 U.S. coals and the 84 coals used are shown. Similar plots between volatile matter and hydrogen or atomic H/C of the 84 coals are also included. Significances of regression coefficient signs for coal composition parameters in the significant correlations found are discussed. Based on these significances, the following relations are shown: (a) coke strength versus average aromaticity, or mineral matter content, of the parent coal; (b) characteristic temperatures of the plastometer and dilatometers, the free-swelling index, or the Gray-King type versus average hydroaromaticity of the coal; and (c) nontemperature parameters of the plastometer and dilatometers versus the physical properties of a certain group of compounds from thermal decomposition of coal. Similarly, significances between the positions of coals in the coal band and the aforementioned relations are also discussed. A structural theory of coal plasticity is proposed. Applications of the correlation results are discussed. Composition parameters, such as carbon, atomic H/C, and calorific value may be used as a basis for selecting coking coals for stronger coke. Plasticity parameters, such as the end temperatures of the plastometer and dilatometers and the free-swelling index, may be used for the same purpose. Based on the best correlations found, coke-strength indices may be estimated to within 4 to 8 units of the observed values; the end temperatures of the plastometer and dilatometer tests, 5° to 10° C.; and the free-swelling index, within 1 unit. Accuracies of all these estimated values are examined, based on the experimental errors of the data involved. Finally, estimations of plasticity parameters from one test with those from others are shown.

Jan 1, 1971

By Kenneth H. Johnston

The Weber pool in Washington County, Okla. (fig. 1), covers an area extending from 2 miles east and slightly north of Bartlesville, Okla., to a point approximately 2-1P tiles northeast of Dewey, Okla. The pool is a part of the area designated by the Standing Committee on Oil Field Nomenclature, Kansas-Oklahoma Division, Mid-Continent Oil & Gas Association, as the Bartlesville-Dewey field. In the following discussion of the geology, development, and exploitation of the Weber pool, the writers, by means of structure maps, cross sections through various parts of the reservoir, and tabulated development data and production statistics, have recorded salient information on a field that was developed before .1910 in an Area that has been repressured since 1926. The total oil production to January 1, 19.0., from the 2,639 developed acres considered in this report, was approximately 14 million barrels, or a recovery of about 5,3;2 barrels per acre, or 227 barrels per acre-foot. The production of the estimated 18 million barrels of recoverable oil remaining in the Bartlesville sand reservoir will require the initiation of additional secondary-recovery practices on some of the leases and the application of a more systematic repressuring program on others.

Jan 1, 1950

By Richard B. Moore

This bulletin presents a summary of available information regarding the sources of uranium, radium, and vanadium, the methods used in treating the ores, and the uses of the finished products. In particular the paper describes the ores found in the United States, giving especial attention to those characteristics of the ores and the conditions of their occurrence that affect mining and treatment. ACKNOWLEDGMENTS. In the preparation of this bulletin a number of persons rendered assistance by furnishing information and by making it possible for us to visit the carnotite deposits in western Colorado and eastern Utah at a time of the year when without this assistance it would have been difficult to obtain satisfactory results. We desire to express our thanks to the following persons: Henry Hall, W. L. Cummings, T. V. Curran, K. D. Hequembourg, David Taylor, H. C. Brown, Forbes Rickard, George W. Alsdorf, Dr. Herman Fleck, Orr J. Adams, C. S. Cherrington, Newt. Stewart, O. B. Willmarth, Angus Cameron, George A. Head, and Lorimer Bros.

Jan 1, 1913

By Ed D. Thimons, Douglas E. Pollock, Andrew B. Cecala, Gregory J. Chekan, Jay F. Colinet, John A. Organiscak

Researchers at the Pittsburgh Research Laboratory (PRL) of the National Institute for Occupational Safety and Health (NIOSH) work to reduce respirable dust exposures in mining operations. One focus of this research is silica dust control for surface and underground operations in the metal/nonmetal mining industry. PRL researchers analyze dust sampling results from the Mine Safety and Health Administration (MSHA) to identify high-risk occupations to guide research efforts. Research is then conducted in an effort to improve existing technologies and/or develop new controls for reducing worker exposure to airborne silica dust. During the last few years, PRL researchers have conducted research related to the following goals: improving protection provided by enclosed cabs on mobile surface mining equipment, reducing dust generation from surface drills, reducing dust levels in iron ore operations, and developing a new method to clean dust from workers’ soiled clothes. A description of each of these controls and subsequent dust reductions quantified through site surveys will be provided.

By Karl E. Starch

This Bureau of Mines report is a background study of severance taxes on mineral production. The rates, bases, and other features of State severance tax legislation as of March 1978 are presented, as are the amounts of State severance tax collections for fiscal year 1977, Some statistical comparisons between severance tax collections, total State tax collections, and total value of mineral production in the States involved are presented to portray the relative importance of severance taxes both in State tax revenue systems and in mineral industry revenues. A general discussion of the purposes and principles of taxation, the unique nature of a mining enterprise, the various types of taxes imposed on mineral production, and the character and rationale of the severance tax and its impacts on mining firms sets the severance tax in perspective. A bibliography of materials on the severance tax is included.

Jan 1, 1979

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

By Oliver C. Ralston, Dorsey A. Lyon

The data reported in this bulletin are largely the result of experiments conducted by the Salt Lake City station of the Bureau of Mines in cooperation with the department of metallurgical research of the University of Utah. The work on lead is only one of the phases of the investigations carried on at that station during the years 1914 to 1916. The results of similar work with zinc ores and with copper and other ores will be published in future reports of the bureau.

Jan 1, 1918

This summary of State laws on explosives wag compiled primarily to ascertain what subjects relating to their control have been acted upon by each State legislature and, in general, how they have been treated. It does not Include any legislation passed after 1942, or any proclamations, regulations, or administrative orders. It does not purport or attempt to be authoritative. If any problem arises involving interpretation of the statutes of any particular State, the original source must be consulted for the exact words used by the legislature. This summary, however, will be useful in determining whether relevant statutes exist, and in locating them quickly, with a minimum of effort. It will be of value also in comparing statutes in other States to determine what construction has been placed upon them by the courts of these jurisdictions or to contrast the varying provisions of many States upon a similar subject. To make these comparisons easier, the statutory provisions for each State have been grouped under several major topics in outline form. Although this sometimes has resulted in disruption of the continuity of individual acts, the increased general clarity and availability of comparable sections have more than justified the procedure followed.

Jan 1, 1943

By W. W. Adams

With production of coal per man-hour of work at a higher level than ever before, the coal-mining industry of the United States established a near-record in lowering the accident rate of nonfatal injuries per million man-hours of exposure in 1940, the injury rate being lower, except for 1939, than in any year since 1930, the first year for which comparable figures for nonfatal accidents were collected by the. Bureau of Mines, United States Department of the Interior. The rate for fatal accidents, on the other hand, was not as low or favorable as in 1939, nor was it as low as in many years since 1910, the earliest year for which fatality rates were complete for all coal-mining States. Accident and employment reports received from mine operators and fatal-accident reports from State mining departments and inspectors showed that 533,267 men were employed at coal mules in 1940, exclusive of the number employed at coke ovens, Although this number represented 6,108 fewer employees than in 1939, a large increase was made in the volume of work performed and in the quan¬tity of coal produced. In 1940 the amount of labor performed at coal mines was 748 million man-hours, a gain of more than 10 percent over the previous year. The average employee worked 199 days, an increase of 20 workdays per man. Production of coal was nearly 513 million tons, an increase of 14 percent, of which more than 461 million tons was bituminous coal and more than 51 million tons was Pennsylvania anthracite. Accidents to mine workers caused the death of 1,388 employees; in addition, 59,781 employees were injured, and each injury resulted in disability of the employee for more than the remainder of the day on which the accident occurred.

Jan 1, 1942

By Thomas R. Bur

The strain and pressure gage methods for evaluating the relative performance of explosives in rock were compared. This comparison was based on a study of the responses of strain and pressure gages to explosion-generated seismic waves. Several explosives) representing a wide range of detonation pressures) were used. In general the relative performance of these explosives) as determined from amplitude) impulse parameter) and energy parameter measurements) is the same if the compressive portion of the strain pulse and the comparable portion of the pressure pulse are considered. Other similarities and differences of the two methods are also discussed.

Jan 1, 1967

By A. J. Kauffman

This inventory of the industrial mineral resources of the Pacific Northwest indicates that each of the States comprising this great region annually produces nonmetallic materials valued at mans million dollars. Commodities or their products that have a large, localized market predominate. These include Portland cement, sand and gravel, stone, clay, and lime. The region's output of magnesite, vermiculite, pumice, and diatomaceous earth is outstanding. The magnesite deposits of Stevens County, Wash., are the largest and most important in this country. Mast of the domestic vermiculite production is obtained from deposits in Lincoln County, Mont. Oregon and Idaho rank third and fourth, respectively, as domestic pumice producers. Production data for diatomaceous earth show Oregon second and Washington fourth among the producing States.

Jan 1, 1952

By Catherine C. Kilgore

The Bureau of Mines investigated the availability of lead and zinc from 104 domestic mines and deposits. Fourteen primary lead and fifty-three primary zinc operations with in situ demonstrated resources containing 27.3 million metric tons (t) of lead and 53 million t of zinc were subsequently evaluated. Potentially 17.5 million t of lead and 2.4 million t of byproduct zinc could be recovered from 14 primary lead operations. Economic evaluations performed in constant January 1982 dollars determined a long-run total cost per pound of recoverable commodity. Including a 15-pct discounted-cash-flow rate of return (DCFROR), 59 pct of primary lead was potentially available at or below $0.32 per pound of lead. Potentially 40 million t of zinc and 5.6 million t of byproduct lead could be recovered from 53 primary zinc operations. Ninety percent of the recoverable zinc is potentially available from currently nonproducing mines and deposits, and a weighted average of their long-run total costs was determined at $0.98 per pound of zinc. At a breakeven (0-pct) DCFROR, these non producing operations had a weighted average long-run total cost of $0.58 per pound of zinc. Sensitivity analyses illustrated that operations that recover byproducts were most sensitive to fluctuating metal prices, producing operations were more sensitive to increased smelter treatment charges, and nonproducing operations were impacted most by the DCFROR.

Jan 1, 1983

By Floyd R. Anderson

Noise control of existing pneumatic drills is difficult and runs into cost, performance and weight penalties. A need exists for a start-from-scratch approach for quiet pneumatic rock drills. The designs based on Leavell Principles which has been successfully used in demonstrating a quiet and vibration free paving breaker, is the concept chosen here. This report shows the feasibility of a quiet stoper for drilling roof bolt holes in coal mines. The work is directly applicable to pneumatic percussive rock drills. The report shows an oscillator based on patented Leavell concepts which results in a vibration free tool and noiseless exhaust. Dynamics of the oscilator is analyzed. Independant rotation of drill rod is provided by an air motor (screw expander) and flushing of cuttings is accomplished by an air ejector in a compact lower housing. The feasibility of no exhaust noise, low drill machine noise, and vibration free casing is discussed.

Jan 1, 1977

By W. J. Wiehagen

The Work Crew Performance Model (WCPM) seeks to define performance variability within similar tasks of an underground work crew and relate observed variability to a cost consequence. Performance variability is described using work site observations to determine the adherence to job elements con¬tained within a standard operating procedure. Key components of the WCPM include (1) job definition through task analyses and the ranking of job elements by perceived cost consequence, (2) observational techniques for establishing performance baselines by measuring adherence to safe and proficient job procedures, and (3) cost linkages between adherence to task procedures and measures of consequence for noncompliance. Data presented within this report were obtained through the study of shuttle car operation in an underground mine in Appalachia. Observed adherence to safe and proficient job procedures by opera¬tors matched well with the consensus profiles (measured through a nominal group technique) with min¬ing personnel. It was also found that experienced operators consistently outperformed less experienced, incidental operators. These findings imply potential use of the WCPM as a practical procedure for thinking systematically about the choices available to reduce performance variability. Field application of the model can offer useful data to evaluate training and financially support performance improvement strategies that can be tested for their ability to reduce human error.

Jan 1, 1994

By J. P. May

This U.S. Bureau of Mines report identifies and evaluates factors responsible for dump-point accidents involving mobile mining equipment. Information regarding the occurrence and severity of the accidents, the industries affected, the types of equipment involved, the primary and contributing causes, and pertinent Federal regulations is included. The aim of this report is to provide information that will aid mine operators in the recognition of hazards associated with mobile equipment operation near the dump points of stockpiles and waste dumps.

Jan 1, 1990

By D. J. Parker

On Thursday, March 18, 1937, the country was shocked by news of a terrific explosion at the New London, Tex., school, which caused the death of 280 pupils avid 14 teachers. The explosion occurred at about 3:05 p.m. in the largest of the 11 school buildings on the campus. Fire 1 shows this building, marked "Main high school building", with respect to other buildings, pipe lines, oil wells, and gas lines or the property.

Jan 1, 1937

By Charles E. Munroe

At the outset of the war the uncontrolled production and possession of explosives obviously became a serious menace to the safety of persons and property and the successful conduct of military opera- tions. Even in the years immediately preceding the entrance of the United States into the Great War explosives were employed in attempts to wreck munitions plants as at Eddystone, Pa., or to inter- rupt transportation and conveyance by demolition of munition-laden cars as at Black Tom Island, N. Y., or by attacks on ships, bridges, and viaducts. Outrages with explosives, such as that which Holt inflicted on the Senate reception room, United States Capitol, were not infrequent, and often caused serious loss of life and injury to persons as well as destruction of property. The regular manufacturers of explosives were keenly alive to this menace and early took such steps as lay within their power to meet it as is shown by the following letter:

Jan 1, 1921

By Alan A. Campoli

OD March 20, 1989, a meeting was held at the U.S. Bureau of Mines Pittsburgh Research Center at the request of Senator Pete V. Domenici of New Mexico. The purpose of the meeting was to engender a technical relationship between the National Laboratories and the minerals industry. During the meeting, the Director of the Bureau of Mines, T S Ary, suggested that since the Bureau is the focal point for mining research in the United States, it would be appropriate for the agency to act as the liaison between the National Laboratories and the minerals industry. As the first step in this process, the author was selected to perform a 6-month investigation to better define the proper role of the Bureau in this area. As part of the investigation, the mining and mineral-related technology available at 21 major U.S. Department of Energy (DOE) Research Laboratories was reviewed. It was assumed that the broad range of scientific and technical areas covered DOE research would provide fertile ground for mining-related technologies. It was hoped that the applicability of DOE research to this liaison effort would be indicative of Federal laboratories in general.

Jan 1, 2011

By Wallace W. Key

The California pesticide industry in 1962 consumed about 30,000 tons of clay, talc, limestone, diatomite, sulfur, and other minerals as fillers (carriers and diluents) in pesticide formulation. This was 10 percent of the U.S. filler requirement for pesticides. About two- thirds of the California total was supplied by a few local mineral producers; the remainder came mainly from Florida, Georgia, and Wyoming. The objectives of this report are to provide data on quantities, sources, specifications, and market conditions for minerals used as fillers by California pesticide formulators. The study disclosed that specifications for mineral fillers have become more rigid and formulators have become more numerous in recent years. During 1962 over 1,200 firms registered 16,000 pesticide products with the Bureau of Chemistry in California. Factors which will tend to diminish future need for mineral fillers include the trend toward greater use of organic sprays rather than dusts and further development of biological controls, such as the development of sterile insect strains.

Jan 1, 1965