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By Chas. F. Jackson

During the past year a special study was made of shrinkage stoping A large number of mines in the United States and Canada which employ this method were visited and their practices were discussed with the operating staffs. The operating data obtained are appended hereto. Data were also abstracted from the literature on other mines and are combined in tables with data personally secured by the author. References are made to these published articles, some of which have appeared as information circulars of the United States Bureau of Mines, in the Transactions of the American Institute of Mining and Metallurgical Engineers, and the Engineering and Mining Journal. Several of the mines referred to which have not been described in individual papers will be described in detail in information circulars to be issued by the bureau. Eventually it is planned to combine and condense the information in these circulars and present the data in bulletin form.

Jan 1, 1930

By Ivan F. Avery

DOMESTIC production of carbon black increased 4 percent in 1962 to 2,056 million pounds. Furnace black output was 8 percent, or 132 million pounds, above that in 1961 and accounted for 90 percent of total carbon black production. Channel black output continued to decline and was 55 million pounds less than in 1961. Carbon black shipments during the year totaled 2,082 million pounds and were 5 percent above those of 1961. About one-fifth of these shipments were exported; the balance were sold domestically. An increase of 180 million pounds in domestic sales was partially offset by a decline of 80 million pounds in exports. Total value of carbon black production in 1962 was $145 million. The average value per pound of 7.06 cents was 0.24 cent per pound less than in 1961. Producers' stocks declined 26 million pounds during the year.

Jan 1, 1963

By J. Koster

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Jan 1, 1939

By G. L. Oldright

This paper is the third1 of a series of five papers that is to appear on smelting in the lead blast furnace. The objects of this investigation are to determine the conditions obtaining within the blast furnace be direct experimentation, and to correlate the behavior of the furnace at various times with the main factors governing the operation of the blast furnace, and metallurgical losses. ACKNOWLEDGEMENTS The writers wish to express their appreciation to the management of the international Smelting Company at Tooele, Utah, for their kind cooperation which made possible the assembling of these data.

Jan 1, 1929

By G. T. Krempasky

In an attempt to develop a suitable precast concrete support for underground use, two different models (1955 and 1958) of a five-piece concrete set were designed, fabricated, and tested under adverse loading conditions. Model 1955 was designed to withstand an ultimate, uniformly distributed, vertical load equivalent to what a three-piece, 12- by 12-inch wood set of intermediate-grade Douglas fir would withstand. A design figure of 138,000 pounds for the vertical load was used on both the 1955 and 1958 models. In addition, the 1958 model was designed to withstand a uniform horizontal load of 7,000 pounds per foot and additional concentrated-point loading. The step- by-step design of each model is presented in the appendixes. A series of five destruction tests was conducted underground on the 1955 model, and results of the tests showed that the type and method of blocking were of major significance.

Jan 1, 1963

By J. P. Connell

The U.S. Bureau of Mines awarded a contract to Morrison-Knudsen, Inc., to evaluate the use of roadheaders in underground mining operations. Road-headers were found to be widely used in mines as construction support units, as development miners, and as stoping machines. However, road-headers were found to have mechanical and electrical problems, to suffer reduced productivity when integrated into the mining cycle, and to create dust problems. Also high capital costs and low utilization and avail-ability cause high amortization costs per ton. This report identifies the roadheader operating problems and offers suggestions for improved mechanical and electrical design as well as manufacturer and owner responsibilities for improved availability. The development of a complex integrated excavation and ground support sys tern is no t warranted until the roadheader itself is made much more reliable.

Jan 1, 1980

By P. H. Mutschler

The Bureau of Mines studied the Chattanooga Shale to determine the quantity and quality of the uranium resources present and to assess specific environmental effects of mining the shale. Geologic data and chemical analyses, mainly concerning a 12-county area of Tennessee, were compiled from previous published and unpublished reports. Uranium resources in the Gassaway Member of the Chattanooga Shale in this 12-county area were estimated to be between 4.2 and 5.1 million tons, contained in 76 to 91 billion tons of shale. These figures represent inground tonnages and do not allow for mining or processing losses. Depending upon efficiency of mining and processing systems, enough uranium could be available to satisfy a large part of the cumulative domestic and world demand through the year 2000. A model was developed which assesses the total tons or acres of shale to be mined if the Gassaway Member were to satisfy 1 percent of the United States demand for uranium in 1991. This partially demonstrates the environmental impact of mining the shale and is easily factorable to any specified demand.

Jan 1, 1976

The following is a Maintainability Design Checklist for coal mining equipment. The purpose of the checklist is to provide a summary of design review points for the maintainability assessment of new or existing underground equipment. It specifically focuses on the identification of equipment design features, tasks, or procedures that impact equipment downtime, repair costs, labor hours and maintainer skill level requirements. Some checklist points are general in nature. The checklist was designed to be used across all categories of underground equipment. The intent is to draw attention to design features and maintenance procedures that will increase maintainability requirements. You are encouraged to adapt this checklist to site specific or machine specific requirements by: Inserting specific performance criteria for various categories of maintenance tasks. For example; all hydraulic lines on a shuttle car should be replaceable in 15 minutes or 25 minutes, etc. Adding or deleting checklist items for different categories of equipment. You would include environmental control equipment, for example, on face equipment and not on shuttle cars or man trips. Adding additional checklist items based on site or equipment specific maintenance histories or experience, company maintenance standards, or other factors.

Jan 1, 2000

By Roy S. Nutter

An expert system advisor consultant to assist a coal mine section foreman is described in this report. The system is designed for an underground continuous miner section that is being specifically used for longwall development. The system provides three methods of operation that include normal operational mode for use underground, a training mode for use in training section foremen under controlled classroom conditions, and a demonstration mode that is free running. The Face Decision Support System or FDSS, is designed to interface with section environmental monitoring equipment and section production monitoring equipment that may appear in the future. This provides automated reprioritzation of the section foreman's job list from the system. The system 1S written in LASER which is written in C and is operated under the UNIX operating system. The objective of the entire FOSS system is to ensure that no job or piece of information important to safety or to production is forgotten because of the immediate problems confronting the section foreman.

Jan 1, 1988

By Joseph J. Wallace

1. The Investigation shows that there are six coal beds of major importance in McDowell County from the standpoint of present production - Pocahontas No. 3, Pocahontas No. 4, Pocahontas No. 5, Sewall, Beckley, and Pochontas No. 6 - and five beds of minor importance - Iaeger, Douglas, Welch, Pocahontas, No. 9, and Eagle. The Pocahontas No. 3 bed contains the largest remaining, known reserves. 2. Known measured, and indicated reserves in all beds, based on a minimum thickness of 174 inches and on 1,800 tons per acre-foot of coal in place, are estimated at 2,217 Trillion short tons as of January 1, 1951. Of this total, 1,731 million short tons are in beds 28 inches and more thick. Areas in each bed were omitted from the estimate because available data relative to the bed characteristics are too meager to make 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 area, such reserves should be added to he total estimated reserves.

Jan 1, 1952

By R. S. Dean

[Methods s of preparing the manganese metal that has been used in chemical and metallurgical investigations have passed through a cycle. Most of the investigations made before the turn of the century, used Moissen's pyrophoric manganese.3/ This material was made by electrolysis into a mercury cathode and distillation in vacuo. The material was essentially pure, and investigations in which it was employed (with proper precautions against oxidation) led to accurate results on tie intrinsic behavior of metallic manganese.]

Jan 1, 1941

By Gary A. Kingston

This examination of Pacific Northwest (Idaho, Montana, Oregon, and Washington) ferrous scrap-industry operations, principally those in Oregon and Washington, points out factors influencing the supply and consumption of scrap materials, such as the complete dependence of steel ingot producers in these States on scrap as a metal raw material and the sizable quantity of scrap exported from Seattle and Portland to Japan. The pattern of the industry is presented as a movement of materials from their diverse sources to the consuming market. The geographic locations of the consuming industries in relation to the areas generating scrap materials and the movement pattern of the supply from source to destination strongly influences the cost of the commodity. The best measure of the scrap supply available in an area is experience in terms of how much scrap was withdrawn at a given price. Scrap availability is not finite, because the return of materials as scrap is secular and influenced by constantly varying market conditions. Steel ingot producers use 75 percent of the approximate 500,000 tons of scrap consumed in Oregon and Washington; steel foundries take 15 percent of the total; and iron foundries, ferroalloy plants, and other miscellaneous consumers utilize the remainder. Also, from 1955 to 1960 an average of about 200,000 tons has been exported annually from Oregon and Washington. The foreign exports are supplemented by lesser shipments to other steel producing States, principally in the western United States. From 1955 to 1960 the preferred and higher value heavy melting scrap grades accounted for about 60 percent of total withdrawals which varied between 600,000 and 950,000 tons annually. Total crap withdrawals from Oregon and Washington are projected to 1.8 million tons by 1985, 60 percent (1.1 million tons) of which will be heavy melting grades. No. 1 heavy melting scrap is most attractive to scrap consumers at $35 per ton or less. Price-supply relationships compared with projected scrap requirements indicate future prices possibly over $35 per ton. High prices over a long period could motivate the Pacific Northwest scrap consumers to produce steel from iron ore. However, technologic changes taking place at integrated steel plants could reduce scrap withdrawals from the Pacific Northwest, which might keep the scrap price sufficiently attractive to obviate production of competitive iron products by the Pacific Northwest scrap consumers.

Jan 1, 1964

By H. E. Heide

"Before the war, the United States was the world’s leading consumer of tin, the industrial applications of which had become widespread. Domestic production was negligible, and requirements were met almost entirely by imports, principally from British Malaya, United Kingdom and China. Average annual imports for the years 1925-1929 amounted to 78,009 long tons.With the advent of war in Europe and signing of the Japanese-German pact, it was realized that foreign sources of supplies were threatened, and steps were taken by Congress to forestall critical shortages of tin and other minerals. These steps in regard to tin included stock-piling, improving reclamation and conservation, increasing South American production, constructing a smelter in the United States for treatment of tin, ores, and intensifying the search for domestic tin deposits. Annual imports were raised to 140,873 long tons by 1941. On 1945, annual imports had shrunk to 37,675 long tons and consumption had been reduced to 52,100 tons of primary and secondary tin but not tin content of scrap alloy.The Strategic Minerals Act, passed by the Congress in 1939, authorized the investigation of domestic tin deposits.As Alaska had supplied virtually all of the domestic output of tin, an investigation of Alaska deposits was undertaken in 1940 and 1941 by J. B. Mertie, Jr., and Robert R. Coats of the Geological Survey.The Lost River lode tin mine on the Seward Peninsula was examined by H. E. Heide of the Bureau of Mines in 1942. Possibilities for developing a significant amount of tin appeared favorable, and exploration of the ore bodies was started in August 1942."

Jul 1, 1946

By H. J. Rose, H. H. Lowry

Considerable information on the organization of German fuel research and recent developments was obtained and published in several combined Intelligence Objectives Sub-Committee Reports. This material, although avail- able in the initial reports, has never been consolidated, so that it may not have come to the attention of many readers. This report gives a summation of the authors' observations at six different research laboratories.

Dec 1, 1947

By Virgil Miller, Glenn L. Allen

The purpose of this report is to present a comprehensive review of the technology of alumina and aluminum production in the former Japanese Empire , which consisted of the Japanese Home Islands and her dependencies , Formosa , Manchuria , and Korea . Pertinent background material and statistics are given when deemed necessary to make the report self - contained and to make clear the factors underlying Japan's tremendous accomplishments in the production of aluminum .

Apr 1, 1949

By George S. Rice

"The emission of hydrocarbon gases from coal beds and contiguous strata causes many accidents in coal—mine workings, the number of fatalities so caused being second only to those due to falls of roof. Gases tend to increase in amount with depth of coal mining, hence the danger of explosion is increased with depth. The pressure of the gas in virgin—coal areas at a distance from mine workings likewise tends to increase with depth from the surface, probably due to corresponding increase in hydraulic head and possibly, when the gas is held in nonporous formations, to greater ground pressure. The rise in gas pressure with depth under usual conditions is shown in wells drilled from the surface and in some coal fields in drill holes into the face of workings; however, under normal conditions of coal formation gas does not issue into workings under high pressure because the coal and adjacent strata have many bedding and joint planes which allow the gas to escape freely at the face of the workings. The rare occurrence of instantaneous outbursts of gas, with violent effects referred to later, constitute the exception.Variations of volume and pressure of fire-damp or methane found in different coal beds by wells at a distance from mine workings, are analogous to variations in volume and pressure of natural gas found in different gas and oil sands, although in general the pressure tends to increase with the depth. Sometimes, however, in tight sands higher in the formation the pressure of gas therein is abnormally high, and on drilling the well deeper gas in the lower strata may be found at lower pressure."

Jun 1, 1934

By L. A. Stewart

This is one of a series of reports prepared by the Federal Bureau of Mines on mining methods, performance, and costs at individual mines in the United States. The primary purpose of these papers is to promote development and conservation of our mineral resources by disseminating technological information on methods, practices, and results that may be applied to the engineering analysis and solution of mining problems. This report discusses the highly selective mining methods of the Jaquays Mining Corp. at the Regal asbestos mine, 45 road miles northeast of Globe, Ariz. The milling method at the Globe plant is discussed briefly, and the extraction ratios of the various grades of fiber are tabulated. The proposed flowsheet of a new mill under construction is shown.

Jan 1, 1961

By Victor R. Spironello

Applications of three experimental design techniques to smelting operations are explained. The report describes a factorial design using three variables at two levels, a fractional factorial design which investigates seven variables, and response-surface methodology for optimization of electric- furnace smelting processes. These methods may be applied with a minimum of trials and at little expense. Further, the writer knows of no reasons why the same methods could not be applied to other operations as well, such as steelmaking.

Jan 1, 1970

By W. A. Grosh

Records show that much of the lead produced in the Upper Mississippi Valley lead-zinc field was taken from natural openings along crevice systems at shallow horizons or at the surface. During the early history of the district, the shallow deposits were worked intensively; but in recent years the production of lead, except as a byproduct of deeper mining for zinc ores, has not been significant. Considering the methods of early mining, the character of mineralization, and the fact that galena can still be found on the surface of the old digging areas, it was reasoned that enough mineralization might remain on and above bedrock to permit, through the use of modern equipment and methods, economical re-treatment of surface material in the digging areas.

Jan 1, 1960

This Bureau of Mines report reviews the development of the world potash industry. The trends leading to the present market situation of oversupply arid low prices, which threaten; the domestic potash industry, are presented and analyzed. Because the major threat to the domestic industry comes from Canadian imports, the report focuses on the comparative economics of United States and Canadian production. The study resulted in these major conclusions: 1. Balance of world supply and demand is foreseeable in 1975, but it could be delayed by planned expansion. 2. Balance of U.S. supply and demand could occur as early as 1974-75 or as late as 1981. 3. Nearly all U. S. production capacity vis-a-vis Canadian competition is now uneconomic. Prices cover out-of -pocket costs for only 30 percent of U.S. production. 4. U.S. producers will be undersold by Canadians in 60 to 90 percent of the U.S. market. Canadians also will have the edge over United States and European producers in export markets. 5. U.S. firms have invested in 60 percent of the planned 1971 Canadian production, and they have large holdings in Saskatchewan. 6. The decline in the U.S. potash industry probably reduced personal income in Carlsbad, Eddy County, N. Mex, the chief potash-producing area in the United States, about $21.5 million between 1966 and 1969.

Jan 1, 1970