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By Bruce F. Grant

"INTRODUCTION The future of oil production in the part of the Appalachian region included in southwestern Pennsylvania; West Virginia, and southeastern Ohio is directly dependent on the maintenance of existing wells. This report presents an analytical study of the methods used in oil-well reconditioning in this area. The study is part of a research program designed to evaluate those means of stimulating oil production that can effectively and economically maintain present oil-production rates and make it possible to keep existing wells in operation. Well-reconditioning work was curtailed during the war; therefore, an abnormally large number of wells in the Appalachian Region is now in need of repair. Because the lubricant content of Appalachian crude: oils is high and the refined lubricating oils an; particularly suited to use in high speed, high-temperature engines, the demand for these crude oils during the war exceeds, the maximum rate of production obtainable under wartime operating conditions. Increases in operating, expenses, inability to meet war-time reconditioning costs, and inflexible price structures caused the abandonment of an alarming number of wells during the past 4 or 5 years.As a means of increasing regional oil-production rates, new drilling in the older fields for primary production generally is uneconomical because reservoir pressures in most of the fields have virtually been depleted and the production rates of newly drilled wells are small."

Feb 1, 1948

By W. F. Dietrich

1. On St. Thomas and St. Croix, and possibly also on St. John, low-quality red-burning clays probably can be developed to provide the major part of the raw materials for structural clay products and earthenware pottery. 2. The potential sales volume for structural clay products is too small to sustain a plant in the Virgin Islands to manufacture such products in competition with Puerto Rico; however, handmade patio tile might be produced successfully. 3. The market for pottery utility wares in the Virgin Islands is too small to justify a plant devoted solely to the production of such wares; but it may be feasible to evolve a diversified community activity to make jugs, pots, casseroles, bowls, charcoal burners, patio tile, and other items.

Jan 1, 1955

Quickly and cheaply consolidate underground slimes to facilitate their use as backfill and permit their easy handling for other reasons. Approach: The slurry containing slimes is pumped into active stopes and electrokinetically dewatered to provide consolidated back fill. How It Works: To densify slimes electro-kinetically two electrodes are placed in the material to be dewatered and densified. Typically, the electrodes are pieces of wire mesh fencing. One is placed on the bottom, and the other is suspended in the slurry near the surface. Figure 1 is a simplified section of a test. A d-c voltage of 100 to 400 volts is applied across the slurry. This causes the solid particles which are in suspension in the water (usually these are negatively charged) to migrate toward the anode; simultaneously, the water moves toward the cathode. Water immediately adjacent to the negatively charged solid particle surfaces contains an excess of dissolved positive ions. When these ions are attracted to the electrode and move towards it, they also exert

Jan 1, 1976

By Robert E. Manning

At present, a need exists for more effective noise control in the coal-mining industry. In particular, new muffler designs with the required acoustic performance are needed for percussive pneumatic drills. Accordingly, the U. S. Bureau of Mines issued a contract to USS Engineers and Consultants to design a muffler capable of attenuating the noise from the air exhaust of a pneumatic drill. The specific objective of the contract was to design and deliver a prototype muffler that would attenuate the air-exhaust noise to 90 decibels on the A scale (90 dbA). The test drill used in this investigation was one used for roof-bolting purposes in coal mines. Using the combined approach of analysis by digital-computer program and experiment by simulated-noise tests, three prototype mufflers were designed and constructed at U. S. Steel Research. The mufflers consisted of a variety of resonator chambers and expansion-contraction chambers, and were of the following sizes: A muffler with a 3- by 5-inch elliptical cross section and about 8 inches in length. A muffler 5 inches in diameter and about 5-1/2 inches in length. A muffler 5 inches in diameter and about 10-1/2 inches in length. These mufflers were subjected to laboratory tests to determine their effectiveness in attenuating exhaust noise, mechanical noise, total drill noise, and simulated noise. All mufflers reduced the exhaust-noise level by about 25 dbA - from about 115 dbA without a muffler to below 90 dbA with a muffler - and thus were successful in meeting the contract objective. Field tests were conducted with the three prototype mufflers at U. S. Steel's Robena No. 4 Mine, and no icing problem was encountered. A fourth prototype muffler was designed to fit around the leg of the pneumatic drill. Tests showed that this kidney-shaped muffler also reduced the air-exhaust noise to below 90 dbA.

Jan 1, 1973

By T. M. Ruff, W. G. McCoy, M. J. Beus, S. Iverson, W. Hasz

Technology to enhance safety during mine hoisting has been developed by researchers at the Spokane Research Laboratory of the National Institute for Occupational Safety and Health. Assessment of current hoisting technology suggests that monitoring conveyance position and load directly from the skip or cage top offers several significant safety advantages. Wireless data transmission schemes and a package consisting of sensors, batteries, and a charger mounted on the wire rope and skip have been developed. A state-of-the-art automated hoisting test facility was constructed to test the concept in a controlled laboratory setting. Field tests in a fill-size shaft are underway.

By P. R. Moyer

"INTRODUCTION The Federal Explosives Act (55 Stat., 863), as amended, was passed by Congress on December 26, 1941, and became effective immediately; it amended the Act of October 6, 1917 (4o Stat., 385). The purpose of the Act was to regulate the manufacture, storage, use, and possession of explosives in order to prevent sabotage and to assure that explosives and ingredients would not fall into unauthorized hands. Under the provisions of the Act, the Director of the Bureau of Mines was authorized to administer its provisions under the supervisions of the Secretary of the Interior.EXPLOSIVES-CONTROL DIVISIONTo administer the Act, necessary personnel were employed in accordance with the appropriation made from a special presidential fund and later by Congress, and the Explosives Control Division was organized as a part of the Health and Safety Branch of the Bureau of Mines constituting the fourth division of that branch. A central office was established in Washington, D. C., and field offices were designated largely at the offices of the Health and Safety Branch throughout the country, and 50 explosives investigators were employed and assigned to work from these offices under the direction of the district engineers of the eight districts into which the United States is divided by the Health and Safety Branch. The territory assigned to each investigator was based on the approximate amount of explosives stored in that area; however, smaller territories were assigned to investigators stationed near the Pacific coast, which was indicated as critical by the armed forces."

Mar 1, 1947

By Joel M. Modd, Stephen P. Holt

"INTRODUCTION Nickel is one of the seven metals designated as strategic by the Army and Navy Munitions Board in 1939, when Congress appropriated funds for the investigation of domestic sources of supply of war minerals. The Mertic nickel lode at Punter Bay, Admiralty Island, Alaska, owned by the Admiralty Alaska Gold Mining Co., was investigated as part of this program.During the period 1919 to 1928, the property was examined the following engineers; L. S. Robe, W. E. Dunkic and S.E. Conbest of the Alaska Treadwell Cr., A, F. Buddington of the Federal Geological Survey, and H. C. Boydell. Henry M. Eakin, in the capacity of consulting geologist, examined the deposit in 1928 and later reviewed data resulting; from exploration recommended by him. In 1936, A. Hoogbom, of the Geological Survey of Sweden, made a very brief report on the deposit based upon information furnished by J. S. Pokovich.A comprehensive study by the Geological Survey of the Punter Bay area, including the Mertic lode, was made during the field season of 1937, with brief examinations in 1936 and 1938. 4/Miyaki, representing the Mitsubishi Company, visited the property in 1937 and in the course of his examination took six samples. G. W. Powel examined the deposit in 1937 and took five samples in the Mertie adit.This report describes the results of the Bureau's work and gives information collected from other sources."

Nov 1, 1946

The first metal-mine accident-prevention course was prepared and published in 1942-45 as a series of seven miners' circulars (Nos. 51-57). The course has been broadened in scope, revised, and brought up to date and is being published as a similar series of seven miners' circulars (Nos. 51-57, revised) on accident prevention in metal and non-metallic mines. These circulars are as follows: Injury Statistics (Miners' Circular 51), dealing with general statistics on injuries from accidents at metal and nonmetallic mines, including causes, costs, and the use of investigations and reports of all injuries.

Jan 1, 1960

By N. Dixon

This report summarizes all work performed under U.S. Bureau of Mines Contract J0377014, "Development and Evaluation of Noise Control Techniques for Taconite Processing Equipment." Three areas of taconite processing equipment, grinding mills, fine screens, and crusher screens have been investigated. Extensive noise and vibration measurements have been made on grinding mills in which the process parameters that affect mill noise have been identified, and the level of shell impact noise around the mill defined. A multiplexing telemetry system was used to obtain shell vibration measurements from a rotating mill. Mill noise control methods were investigated and a partial mill barrier was built and tested on a semi-autogeneous mill. A noise reduction of approximately 3 to 6 dBA was achieved on the falling side of the mill. The use of rubber mill liners on autogenous mills has been evaluated. The noise sources on fine screens have been quantified, and noise control treatments developed. Noise reductions of 11 to 13 dBA were achieved at positions around the fine screen and some in-service testing has been done. Noise measurents of crusher screens were obtained and noise control through resilient screen decks appears to hold the most promise. Additional benefits might be lower life-cycle cost, since the service life of resilient decks is claimed to be longer than steel.

Jan 1, 1983

By Compiled by Staff

"INTRODUCTIONThe U.S. Bureau of Mines (USBM) was established in the public interest to conclude inquiries and scientific and technologic investigations on mining and the preparation, treatment, and utilization of mineral substances; to promote health and safety in the mineral industries; to conserve material resources and prevent their waste; to further economic development; to increaseee efficiency in the mining, metallurgical, quarrying, and other mineral industries; and to inquire into the economic conditions affecting those industries. The organic act of the Bureau, as amended by Congress and approved February 25, 1913, made it the province and duty of the U.S. Bureau of Mines to ""disseminate information concerning these subjects in such manner as will best carry out the purposes of this Act.""In accordance with this directive, USBM reports the findings of its research and investigations in its own series of publications and also in articles that: appear in scientific, technical, and trade journals; in "" proceedings of conventions and seminars; in' reference books; and in other non-USBM publications. The number of these reports, the wide range of subjects they cover, and the variety of mediums in which they appear make this kind of list both necessary and valuable.This edition describes reports and articles published during calendar years 1992 and 1993. It supplements the 50-year list of Bureau publications from July 1, 1910, to January 1, 196O 2; and these 5- year lists of publications and articles: from January 1, 1965, to December 31, 1969 4, from January 1, 1970,to December 31, 19745 , from January 1, 1975, to December 31, 1979 6 , from January 1, 1980, to December 31, 1984 7 , and from January 1, 1985, to December 31, 1989 8."

Jan 1, 1994

To alleviate the hazard to personnel and danger to equipment caused by fires on large, mobile vehicles. The Approach: A system which automatically senses a fire at its early stage of development, warns the driver of the danger, and activates fire extinguishers in the zone of combustion, How It Works: The automatic fire protection system utilizes both thermal and optical sensors to detect the heat or light given off by a fire in the area of concern (Fig. 1). The system warns the driver of the hazard and then automatically extinguishes the fire with pressurized S-C class powder. The system can also be activated manually from the operator's cab or from ground level. Further, the automatic sequencing of the system can be manually overridden by the driver if he determines that the fire sensors have malfunctioned to cause a false alarm.

Jan 1, 1974

By C. A. Geffen-Fowler

This report, sponsored by the Bureau of Mines, presents the results of an examination of the safety of the Blind Shaft Borer (BSB) shaft sinking system and an alternative modified BSB design concept in comparison to conventional shaft sinking technology. Detailed study of the two systems was also performed to identify and recommend design changes for optimum safety conditions. A comparison of the BSB systems with conventional shaft sinking was made on the basis of relative risk levels. Risk incorporates both the frequency and the potential consequence of accidents. A safety evaluation of the component operations of the two BSB systems was performed using a Failure Modes and Effects Analysis (FMEA) methodology. The results of this analysis show generally that both BSB systems are safer than conventional shaft sinking. The potential risk of conventional shaft Sinking operations could be reduced by over 30%, on the average with the use of the original BSB system, and by an average of about 10% with the modified BSB. Design change recommendations to further improve the safety of these systems include a better fire suppression system, improved man haulage systems and more compact hydraulics. An operational safety manual was also developed for the modified BSB system.

Jan 1, 1981

By David E. Van Dillen

The computer program described in this user's guide provides for the static, three-dimensional, linear and nonlinear analysis of structural and geological systems by the finite element method. The guide describes the capabilities and general features of the program and shows how input is prepared. A number of recent advances in finite element theory and computer technology are incorporated in the program. Nonlinear material properties are provided for, including isotropic, anisotropic, and time-dependent material properties, gravity loading, simulation of a sequence of excavation or construction, and a slip or joint element. The finite elements include beam, rod, axisymmetric and plane quadrilateral, hexahedron, thick shell, axisymmetric and plane joint, and a three-dimensional joint. The program also has an automatic mesh generator to minimize user input preparation for continuum finite element meshes.

Jan 1, 1981

By E. G. King

Heat of formation values for mercuric sulfide appear in all the comprehensive listings of thermodynamic data, but experimentally determined entropy values have been lacking. Consequently, all free energy calculations involving mercuric sulfide have been based upon estimated entropy values. This paper reports Bureau of Mines measurements of the low-temperature heat capacity of red mercuric sulfide (cinnabar) and the entropy value at 298.15° K. derived therefrom. The entropy value was combined with heat data to obtain free energy values for the formation of red mercuric sulfide from liquid or gaseous mercury and from rhombic or gaseous diatomic sulfur.

Jan 1, 1962

By J. Douglas Causey

A U.S. Bureau of Mines study indicates over 200 million yd3 (153 million m3) of cinder resources occur in the Mount Washington Wilderness. No future demand for the deposits is anticipated. Based upon the geologic environment, the area is considered favorable for discovery of geothermal resources. INTRODUCTION The Mount Washington Wilderness, located about 32 mi (51 km) west of Bend, Oregon, contains 46,655 acres (18,881 ha) (fig. 1). A 6,300-acre (2,550-ha) addition on the northeast and east boundaries has been proposed by the Forest Service under RARE II. The U.S. Geological Survey made regional geological, geophysical, and geochemical surveys, and the U.S. Bureau of Mines examined, analyzed, and evaluated the economic potential of prospects and commercially important mineral resources.

Jan 1, 1982

A system to continuously measure the concentration of radon in mine ventilating air has been developed and tested in a uranium mine. In use, the air/radon mixture to be monitored is pumped through filters into a scintillation cell where nuclear decay of the radon produces flashes of light. These are electronically counted, giving a quantitative measure of the radon present. Air is continuously drawn from the mine atmosphere into the radon sensor box. This air sample passes through two filters into the detector cell as shown in the schematic diagram. A portion of the radon in the detector cell will experience nuclear decay, producing polomium 218 and an alpha particle. The alpha particles from the fraction that decays strike a zinc-sulfide coating on the inside wall of the cell and produce flashes of light. These enter a photo-multiplier tube which records each flash as an electrical pulse. An amplifier increases the voltage of each pulse, allowing electronic screening to remove noise and other undesirable pulses. The remaining pulses are counted by a conventional data acquisition system.

Jan 1, 1978

By Donald L. Siebert

This profile study of the commercial secondary aluminum industry examines not only the elements that form the industry but also the technological contributions of each toward industrial growth. Concise descriptions of processing methods trace aluminum scrap from generating sources to marketable industrial and consumer goods. Economic and marketing appraisals are used to illustrate the impact that recent technology has had upon the secondary aluminum industry. Price, supply, demand, competition, and substitutes are selected as components of an economic model of the secondary industry and are used to illustrate the aggregate effects of technological changes. The final section is a conceptual look at the future in which sensitive economic indicators (such as die casting in the automotive and appliance industries) are examined as well as the problems of conserving mineral resources by retrieving secondary aluminum from solid waste.

Jan 1, 1970

By Doss H. White

Alabama's non fuel mineral industry produced $560.6 million of mineral commodities in 1990. This was an increase of $99 million over the 1989 value and a new State record, a record achieved despite the slowdown in the national economy. This was the first year that Alabama's mineral value exceeded one-half of 1 billion dollars. The value of stone and cement, the two leading mineral commodities in terms of sales, increased $71 million over that reported for 1989 and was the primary reason for the new mineral value record. The State ranked 21st among the 50 States in total mineral value and contributed 1.68% of the total U.S. mineral value of $33.3 billion.

Jan 1, 1992

By A. N. Baldwin

This report documents the work performed under Bureau of Mines Contract J0265029 to study and develop two innovative mining systems: ? An underground auger capable of augering into the right and left ribs without repositioning the machine ? A conventional mining system employing recently developed innovative machinery. The report is separated into two volumes to document the two studies separately. Volume I describes work performed and the recommended concept for a bidirectional auger. Volume II describes the studies of mining equipment performance and mining plans developed to determine a conventional mining plan offering improved productivity.

Jan 1, 1977

Reduce the respirable dust exposure of the roof-bolter operator when downwind of the continuous miner, particularly in mines where respirable dust standards are more stringent because of silica in the respirable dust. Dust Sources If roof-bolter dust levels are excessive, the bolter dust collector should first be checked to ensure that it is operating properly. (Technology News No. 219 provides information on how to spot and repair bolter dust collector problems). If the roof-bolter dust collector is operating properly and dust levels are still excessive, then the source is most likely a continuous mining machine operating upwind. In many sections, the roof-bolter operator must work on the return side of the continuous miner during part of the production cycle. In three-entry longwall developments with single split ventilation, this may happen as much as one-third of the time. Factors which pro-mote high quartz dust exposure are:

Jan 1, 1985