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By M. Carrales

This Bureau of Mines report presents information on the sulfur content of crude oil in the United States and in some foreign countries. Data are presented for oil produced in 1971 from fields in 26 States that accounted for about 76 percent of total U.S. oil production; the foreign data cover fields in 24 foreign countries that accounted for about 64 percent of the total oil produced from these countries in 1971. Most of the data are presented in tabular form.

Jan 1, 1975

By John Gross

From the time when man first pounded one rock upon another or used heat and sudden chilling with water to disintegrate rock, the art of crushing advanced but slowly to the mule-driven arrastre and the Chilean mill stage until the advent of power-driven appliances made material progress possible. The combined efforts of manufacturers and operators have made modern machines highly efficient mechanically. Although marked progress has been made along mechanical lines, the theory and conception of underlying principles have not advanced so rapidly. This lack of advance in theory may be attributed to the unfortunate situation resulting from the controversy as to whether the Rittinger or the Kick law is applicable to crushing. Many pages of the technical literature are burdened with theoretical discussions in favor of one or the other of these laws, which have tended to cloud rather than to clear the atmosphere.

Jan 1, 1938

By Lloyd A. Morley

This Bureau of Mines publication presents a comprehensive review of mine electrical power-system theory and practice. It discusses fundamental theory and the vital aspects to be considered in planning and designing mine electrical power systems. The report is divided into three major sections. The first presents the history of electricity in mining and the fundamentals of electrical phenomena and components. The second focuses on power-system components: motors, grounding systems, cables, and protective equipment and devices. The final section includes mine power-center equipment, switchhouses and substations, batteries, and mine maintenance.

Jan 1, 2003

By George Markon

The importance of United States coal exports as a component of the national economy, the potential for growth of these exports, and the inter-national character of this sector of the coal industry are described in this report. The report summarizes some of the many background elements in the rise of United States coals to preeminence in highly competitive world markets. It presents some insight into this important sector of United States industry and the positive contribution of this sector to the Nation's balance of payments. It contains pertinent basic statistics on production, trade, and consumption of coal in most major markets for 1960-66. The report examines the movement of United States coals from mines to export markets, tracing and describing origins, exit ports, prices, and trends as well as inland and ocean freight rates and other data vital to an under-standing of some of the practices and complexities of the United States coal markets abroad. A brief sketch of coal production and consumption in principal importing countries is also presented with a short review of some of the more current practices and problems of these countries. Coal produced in inland areas of the. United States can be moved to and distributed economically within coal-producing countries overseas and in Canada. Quality coals from the United States can successfully compete with foreign coals in nearly any area of the world on a truly economic basis because of their high grade and their low cost which derives from the high productivity of the miner and from reasonable ocean freight rates. Because of tariffs, trade embargoes, quotas, and other restrictions, how-I ever, foreign coal markets are relatively limited. Further limitations are imposed in some countries by economic conditions which restrict all imports as a matter of financial and economic necessity. Despite these obstacles, United States coals have brought lower cost quality coals to a large segment of the foreign energy market.

Jan 1, 1968

By William H. Tavenner

1. The 1952 Annual Report of the West Virginia Department of Mines lists nine beds that arc being mined in Logan County, of which the Cedar Grove and Chilton are the most important. The Cedar Grove group, No. 2 Gas, and Alma beds have the largest remaining reserves, in the order given. 2. Known measured and indicated reserves in all beds, based on a minimum thickness of 14 inches and 1,800 short tons per acre-foot of coal in place, are estimated at 5,411 million tons as of January 1, 1954. Of this total, 3,939 million tons is in beds 28 inches and more thick. Areas in each bed were omitted from the estimate because available data relative to the bed characteristics were too meager for making an estimate that conforms with the definitions of measured and indicated coal adopted for this study. Should future drilling or development prove reserves in these areas, such reserves should be added to the total estimate reserves.

Jan 1, 1956

By Thomas K. Matson

The coal reserve base in the Western United States is presented for coalbeds amenable to extraction by underground mining methods. The Federal Bureau of Mines has abstracted data on the quality and quantity of coal resources/reserves from numerous State and Federal publications and modified such data as necessary to allow computer storage and retrieval. Tonnages are compiled by State, county, coalbed, and rank, and allotted to sulfur categories by statistical apportionment. The coal reserve base in those States west of the Mississippi River, amenable to underground mining, is estimated to be approximately 131 billion tons. Of this total, about 30.8 billion tons are bituminous coal, 100.2 billion tons are subbituminous coal, and 126.4 million tons are anthracite. Lignite is not considered for underground mining in this report. Included in this report is a glossary of terms applicable to a classification system for coal resources and reserves as jointly defined by the Bureau of Mines and U.S. Geological Survey. The purpose of this system is to provide for direct comparison or compilation of various resource/reserve data.

Jan 1, 1975

By David J. Hoadley

This report describes the development and underground operation of a semi-automatic, raise climber, Man and Supply Hoist System designed for stope access in underground metal and nonmetal mines. Demonstrated capabilities of the system include a 4000-lb payload capacity, control from the traveling cage and from up to five remote stations, operating in vertical or inclined raises 5 ft in diameter and up to 300 ft in length and a travel speed of 50 ft/min. The 'system has the capability of operating in crooked raises because the conveyance climbs two stationary wire ropes suspended down the raise. The drive unit is electrically powered with power and control signals supplied to the drive unit through an armored cable also suspended down the raise. The system has been designed for portability, ease of installation and minimum raise development. The system can be installed by two men in five shifts. The hoist has been demonstrated successfully in two underground applications. The first demonstration was in a 5-ft diam, 60 deg inclined raise over a 2-month period. The second demonstration utilized a vertical 5-ft diam borehole to access a blast-hole stoping area. The system successfully provided two shift-a-day service over a 7-month duration demonstration. This report provides a detailed description of the hoist design and its demonstrated performance in two mine applications.

Jan 1, 1981

By R. J. Hundhausen

The Shamrock copper-nickel mine in Jackson County, Oreg., was formerly a part of the Chisholm mercury property. In 1948 new owners advanced the old workings 40 feet to reveal encouraging widths of copper-nickel sulfide, ore on the Shamrock claim. When the owner's funds became exhausted, the Bureau of Mines carried on the development in 1949-50, completing 1,650 feet of bulldozing trenching, 396 feet of drifting, and 3,419 feet of diamond drilling. The Bureau's trenching disclosed a separate surface deposit 600 feet south of the mine deposit. This and the previously known deposit subsequently were diamond-drilled. The underground deposit has a known length of 100 feet, a dip length of. 100 feet and a width varying from 1 to 25 feet. The surface deposit is 200 feet long, 200 feet deep, and 5 to 38 feet wide. Neither deposit has been entirely delimited by development to date.

Jan 1, 1952

By Oliver Bowles

The National Granite Commission at its annual meeting in Norfolk, Va., in January, 1930, passed a resolution requesting the Bureau of Mines to conduct an economic study of the granite industry. In with this request a preliminary review has been made of trends in the production and uses of block granite.. Some unfavorable conditions were thus brought to light, and certain suggestions regarding a more orderly and consistent growth in the industry are herein discussed. The results of the study are, presented in this report for the earnest consideration of. the industry, and comments are invited, not only on this report but as to future work that might be accomplished by the Bureau of Mines. The authors desire to acknowledge many helpful suggestions and comments from Paul M. Tyler of the Bureau of Mines and from Harris F. Sherman, secretary of the National Building Granite Quarries Association. Miss A. T. Coons of the Bureau of Mines rendered valuable assistance through her wide knowledge of granite statistics. The block granite industry has shown little expansion during recent years. While the value of the annual production has grown from about $14,000,000 in 1904 to nearly $25,000,000 in 1928, the increment in value is caused mainly by mounting prices rather than by increased production. Even granite for memorials shows a very small advance in production volume, although the value has increased from about $3,500,060 in 1904 to more than $11,000,000 in 1928, which is the most consistent growth of any branch of the industry. The value of building granite has fallen for a number of years much below the figure for 1904, and in 1928 was very little in advance of the value attained 24 years previously. The use of granite paving blocks and rubble has shown a gradual decline.

Jan 1, 1931

By B. C. Burgess

This paper, describing the milling practices at the Minpro plant of the Tennessee Mineral Products Corporation, Spruce Pine, N. C., is the first of a series being prepared by the U.S. Bureau of Mines on feldspar milling methods and costs in the various feldspar producing areas in the United States. It describes not only the latest practices in feldspar grinding but includes studies of the cost of producing ground feldspar. These cost studies, obviously of interest to every consumer and purchaser of feldspar and to all feldspar grinders, are also of value to the small operator, who is generally prone to understimate his real costs. It describes the latest practices in feldspar milling and includes detailed costs of grinding. The cost tabulations presented show operating expenditures only and not total production costs. Details of costs are given only to the extent that they are essential to the technical discussion and study of the methods employed. A description of the recently installed milling unit for the preparation of granular glasspar by graded crushing, and magnetic separation is of particular interest. It illustrates how highly specialized feldspar milling has become, and to what an extent grinders are going to supply consumers with the products best suited for their particular needs.

Jan 1, 1931

By Mark S. Sanders

The purpose of the present study was to develop and test improved Type V workvests for use on dredge operations. The goal was to design workvests that would be more comfortable to wear, would interfere less with task performance, and would better meet the needs of dredge workers. It was hypothesized that by attaining these goals, the resulting vests would be worn more often and would be kept buckled more of the time than traditional vests. The study involved three major phases. In Phase I, visits were made to dredge operations and a definition of the problem was developed. Problems with current vests were identified and working conditions and tasks surveyed In Phase II, prototype vests were developed and laboratory tests were per-formed to assess comfort and interference. In Phase III, the prototypes were modified and field tested with actual dredge operators and workers.

Jan 1, 1985

Data released by the Commerce Department's Bureau of Economic Analysis show continued gradual change in the real GNP's rate of growth in 1984, which has eased from an annual growth rate of 10.1 percent in the first quarter lo 7.1 percent in the second quarter, and then to 2.7 percent in the third quarter. The automobile industry strike in the last half of September had only a small effect, estimated at less than a 0.1 percentage point reduction in the growth rate. Among the components that comprise the GNP, personal consumption and fixed investment grew at lower real rates in the third quarter than in the second quarter, while net exports decreased. Personal consumption expenditures increased $0.4 billion in the third quarter, compared with an increase of $20.1 billion in the second quarter. Nonresidential fixed investment increased $3.9 billion in the third quarter, compared with $9.6 billion in the second quarter. The other component of fixed investment--residential investment--increased from $60.8 billion in the second quarter to $61.2 billion in the third quarter. Real net exports of goods and services decreased $1 1.3 billion in the third quarter, compared with a $3.1 billion decrease in the second quarter. Although exports increased from an annual rate of $144.7 billion to $150.2 billion, imports increased much more, from an annual rate of $1 56.2. billion to $172.8 billion (table 1).

Jan 1, 1984

By B. G. H. Thomas, W. P. Yant, A. C. Fieldner, R. R. Sayers, W. J. McConnell

"One of the outstanding problems confronting automotive engineers in attempting to construct motors of greater economy is that of eliminating the ""knock"" from the operation of the engine. Recent investigations of this detonation or knock in internal-combustion engines, especially of the high-compression type, have demonstrated that it can be eliminated or reduced by decreasing the reaction velocity of combustion by adding small quantities of certain compounds to the gasoline, This makes it possible to use engines of a higher compression ratio, thereby greatly increasing the mileage per gallon of gasoline consumed. The savings in fuel reserves from increasing the proportion of crude oil marketable as motor fuel and in permitting the designing of more efficient engines are obvious.Ethyl gasoline, one of the widely used anti-knock fuels, is ordinary motor gasoline to which has been added 3 c.c. of tetraethyl lead and 2 c.c. of a halogen carrier, as ethylene dibromide or trichiorethylene, or approximately 0.06 per cent of the lead compound and 0.04 per cent of ethylene dibromide by volume. Ethyl gasoline should not be confused with ethyl fluid, which is a mixture of concentrated tetraethyl lead and ethylene dibromide in the prowler proportions for mixing with gasoline, but is not a motor fuel and is not sold to the public. Also tetraethyl lead is not a motor fuel, and likewise is act sold to the public."

Dec 1, 1924

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 Wilbert J. Huff

For the past 9 years , the technical studies conducted by the Explosives Division of this Bureau have been summarized in a series of reports issued annually . The following account presents investigations undertaken from July 1 , 1943 , to June 30 , 1944. The work is detailed under a number of main headings corresponding to the organizational structure of the Division , the various activities being under the immediate direction of unit chiefs , who report directly to the author . Specific credit , however , is due to the individual unit leader and his assistants .

Jan 1, 1945

In 2006, a total of 2,113 coal mining operations reported employment to the Mine Safety and Health Administration (MSHA).1 Coal mines comprised 14.2% of all mining operations. ? Bituminous mines comprised 92.5% (n=1,955) and anthracite mines 7.5% (n=158) of coal mining operations. ? Approximately 71.0% of all coal mines were located in three states: Kentucky (29.2%), West Virginia (21.8%), and Pennsylvania (20.3%).

Jan 1, 2008

By Launa G. Mallett, Jr. Brnich

Overview: The first step to emergency preparedness and maintaining a safe workplace is defining and analyzing hazards. Although all hazards should be addressed, resource limitations usually do not allow this to happen at one time. Risk assessment can be used to establish priorities so that the most dangerous situations are addressed first and those least likely to occur and least likely to cause major problems can be considered later. Purpose: This training package was developed to assist instructors as they (1) determine how to use risk assessment to improve safety preparedness and (2) present risk assessment concepts and tools to trainees. The concepts and tools presented here can be applied to any mine hazard.

Jul 1, 2003

By R. G. Warncke

In the 1953 National First-Aid and Mine Rescue Contest, 58 teams from 9 States participated, 14 teams from 6 States in mine rescue and 47 teams from 9 States in first aid. Three of the teams were combination teams in that the same team participated in both the mine rescue and first-aid contests. The States represented and the number of teams from each State are shown in table 1. [ ] The contest was conducted in accordance with the general rules prepared by the Rules Committee and approved by the General Committee of the National First-Aid and Mine Rescue Committee.

Jan 1, 1955

By D. E. Van Dillen

Three-dimensional structural analyses of three instrumented areas of a deep, longwall coal mine have been performed using the finite element code BMINES. The three Instrumented areas include two single-entry portions and one double-entry portion of the Sunnyside No. 1 Mine, Sunnyside, Utah. The finite element models simulated the sequence of excavation in each test area: the advance of the entry, installation of structural supports, retreat of the longwall, caving behind the longwall, and accumulation and loading of the gob. The structural supports considered in these finite element models include rock bolts, wood cribs, concrete cribs, steel arch sets, and chocks. Mechanical simulation of the geologic environment is achieved through elastic/ perfectly plastic material models employing anisotropy to represent finely layered regions of the medium. The results of these calculations are com-pared with the instrumentation readings from the mine. These measurements include closures, crib loads, rock-bolt forces, and stress growth.

Jan 1, 1978

By F. S. Boericke

"INTRODUCTION The mineral found in natural-chromite deposits is never pure Fe0.Cr203, but rather one in which the Fe0 and Cr203 are in part replaced by Mg0 and A1203, respectively. The purest gravity concentrates from many domestic de¬posits consist of a mineral referred to as ""picotite,"" in which this isomorphous replacement is such that the ratio of chromium to iron is low. The Bureau of Nines has investigated methods of chemically beneficiating ores that contain too much iron to be classed as ""high-grade"" chromite 3/ Early investigations 4/ demonstrated that high-iron chromite or picotite ores can be roasted with carbon to obtain selective reduction of the contained iron, and that most of this reduced iron can be removed by acid-leaching the roast products to produce residues of higher chromium-to-iron ratios. tests 5/ indicated that commercially acceptable reaction rates cannot be obtained at roasting temperatures below 1,3000 C., using solid carbon as reducing agent. By this high-temperature reduction and subse¬quent acid-leaching, however, all ores investigated, regardless of the original composition, readily yielded residues considerably better than the minimum specifications for high-grade chromite.In an effort to obtain satisfactory reduction of chromite at lower temperatures, liquid and gaseous seducing agents were tested with varying success. Of the several reducing agents used, methane appeared to be the most promising and was shown to be highly effective at temperatures between 1,000º and 1,100º C., roughly 300º below the roasting temperatures necessary in solid carbon reduction. Further experiments indicated that mixtures of methate with some diluent (hydrogen or other nonoxidizing gas) gave better reduction than did methane alone."

Feb 1, 1946