Search Documents

By S. H. Lorain

The Minah silver-lead mine in the Wickes district, Jefferson County, Mont., produced substantial quantities of silver-lead ores in the 1890's. The mine has been abandoned since the "silver panic" of the early 1900's. As a part of the Bureau of Mines: program to develop new sources of lead to overcome the growing shortages of that metal, a development project was started at the Minh mine in April 1946 and continued until June 1947, during which 5,600 feet of angledozer trenching and. 1,093 feet of core drilling were completed on the main vein and nearby parallel veins: As a result of this work, interest in the property was stimulated and private operators are now engaged in reopening the mine. This report discusses the past history, geologic setting, and the recent and early operations of the mine.

Jan 1, 1948

By E. R. Palowitch

Coal wasted with mine refuse represents losses in overall recovery of merchantable coal to the mine operator and a concomitant reduction in domestic reserves of available coal. Fraser, Kelley, and Graham3/ in studying the available coal in mine refuse in the Pittsburgh district of western Pennsylvania have estimated that at least 1 ton of mine refuse is produced for each 10 tons of merchantable coal and that 20 percent of this mine refuse might be recovered as salable coal by mechanical cleaning. SUMMARY This investigation dealt with the mechanical recovery of coal from wine refuse by a dense-medium washery employing pulverized mine rock as the dense medium and operating at a rate of 175 tons per hour. Two types of mint refuse were tested: Freshly mined and that .which had been mined 2 years before and piled on a waste dump.

Jan 1, 1955

By A. C. Johnson

This report is one of a series being prepared by the Bureau of Mines on exploration, development, mining methods, and costs at various mines in the United States. It describes operations at the Black Rock mine, Wah Chang Mining Corp., Mono County, Calif. The purpose of these reports is to promote development and conservation of our mineral resources by disseminating technologic information on mining methods, practices, and costs. The Black Rock tungsten mine of the Wah Chang Mining Corp. is 33 miles north of Bishop, Calif., in the Benton Range, Mono County, Calif. The property was acquired in August 1950 and a well-planned program of exploration, development, and exploitation resulted in a good production record with low costs. Operations were halted in July 1957, about 6 months after suspension of the tungsten purchase program by the Federal Government.

Jan 1, 1960

By D. S. Kingery

Investigations over several years have disclosed that the principal manners of occurrence of shuttle-car injuries are in order: 1. Victims in contact with roof or crossbars. 2. Victims in contact with ribs or timber legs. 3. Victims falling from, or jerked from, shuttle cars. 4. Victims in contact with overhanging brows or protruding pine for pin timbers, or water lines. 5. Contact with persons or collisions with parked equipment. 6. Victims injured by roof falls or falling timbers caused by knocking out roof supports with shuttle cars. 7. Victims injured by runaway shuttle cars. 8. Victims injured while loading or unloading timbers or other materials from shuttle cars. These recurring types of shuttle-car accidents reflect the physical conditions of the working sections, certain safety deficiencies in shuttle-car maintenance and design, and unsafe practices by operators.

Jan 1, 1952

By A. J. Kraemer

This paper on the physical and chemical properties of crude oils from California fields is one of a series of reports on the on the districts of the United States. The paper includes a short discussion of results, tabular data, and individual analyses of eight. California crudes. Analyses of other crude oils from California have been published it Reports of Investigations 2595, 2608, and 2846. The samples were obtained by members of the San Francisco office of the Bureau of Mines. The collecting 65 samples was facilitated by the courtesy of representatives of oil companies in California. The methods used in testing and analyzing the samples are described in detail in Bureau of Mines Bulletin 207. A discussion of the interpretation of crude-oil analyses, as made by the Bureau of Mines, is given in Bureau of Mines Report of Investigations 2806.

Jan 1, 1931

By Rogers F. Davis

This publication has been prepared to supply manufacturers and industrial users a listing of mobile diesel-powered equipment and subassemblies approved and certified by the Bureau of Mines for use in nongassy noncoal mines and tunnels. This revised and supplemented listing supersedes an earlier publication2 released in 1963. Testing of diesel-powered equipment is one phase of the Bureau's program of health and safety that concerns approval of electrical and diesel equipment designed to prevent explosions, fires, shocks, or toxic hazards in underground mines, when such equipment is used and maintained properly. Manufacturers submit machinery and component parts to the Bureau for study of their design, safety features, and use. Equipment must pass exacting tests and must meet strict requirements established through research and experience and outlined in the Bureau's permissible schedules before the Bureau approves it for safe use in mines.

Jan 1, 1968

By Lawrence Y. Marks

During the mineral survey of the Bob Marshall Wilderness and study areas by the author in 1971, 1973, 1974, and 1976 (Marks, 1978), the area designated Reservoir-North (RARE II No. H1-485) in January, 1979, (U.S. Forest Service, 1979) was examined, along with other lands adjacent to the earlier study areas. However, the 1978 open-file report covered only areas originally designated for study. The present report on Reservoir-North is based on earlier work. No work has been done in the area since 1976. Mineral Appraisal Reservoir-North RARE II area (No. H1-485) is in the Northern Disturbed Belt which has been identified as having high potential for natural gas accumulations and lesser potential for oil accumulations (Mudge, 1978). Oil and gas lease applications in the area, indicate interest by oil companies.

Jan 1, 1981

By Michael J. Potter

Native asphalt was produced by five companies in two States, Texas and Utah. Bituminous limestone, used primarily as a paving material for street and road repair, was produced by White Uvalde Mines and by Azrock Industries Inc., Uvalde County, TX. In June, Azrock Industries was purchased by the R L. White Co. Gilsonite, a solidified hydrocarbon found only in Utah and Colorado, was mined by American Gilsonite Co., a division of Chevron Resources Co. (a subsidiary of Standard Oil Co. of California); by Ziegler Chemical and Mineral Corp.; and by Hydrocarbon Mining Co. (a subsidiary of Oberon Oil Inc., a Utah corporation) from properties in Uintah County, UT. Gilsonite is used for a variety of purposes including automobile bodysealer, light-weight aggregate for cement used in oil well drilling, asphaltic building board, protective coverings, anticorrosive paints, and roofing compounds.

Jan 1, 1985

By Wesley Hermanson

Canopies were designed, fabricated, installed, and demonstrated for mining machinery in 3-foot coal seams. A Wilcox PJ20 Auger miner, a Wilcox Bolter, a bee Norse 245 miner, and an Elkhorn Scoop AR3 modified to AR4 were fitted with canopies. The Wilcox Bolter canopy was hydraulically adjustable in height; the rest were manually pin adjustable. The machine operators' comments were adverse in each case. Restriction of visibility and body constriction into unaccustowed and tiring attitude were major objections, causing increased hazards and fatigue. Recommendations are made that roll bar protection be furnished in place of canopies for 3-foot seams to provide partial protection by deflecting and supporting roof falls but not covering the head of the operator. In this way, the effect on visibility would be minimized and fatigue from body restriction would not be increased.

Jan 1, 1976

By John C. Franklin

The Bureau of Mines conducted extensive laboratory and limited field tests to determine whether a polymeric material could effectively reduce the emanation rate of radon gas from uranium ore. In the laboratory 46 different single-coat materials and 14 two-coat applications were tested. The laboratory tests showed that up to 100 percent of the radon gas could be sealed into the rock. Materials tested in the laboratory were polyesters, furan resins, epoxies, latices, and totally inorganic coatings. From the laboratory work six different materials were selected for field testing. The first test was single-coat materials in five static chambers; the second test used two-coat applications in an open chamber. Both tests were conducted in the Dakota mine at Grants, N. Mex. During the second test, the amanation rate of radon gas was reduced up to 62 percent.

Jan 1, 1975

The head loss data for coal slurries over a range of concentrations and velocities and the laboratory screen analysis were selected as areas for investigation in the data analysis performed. The analysis resulted in the following: (1) Size distributions for the coal used in the horizontal pipeline tests were fitted to the Rosin - Rammler distribution function. Each of the fits was significant. Corresponding Rosin - Rammler parameters were obtained which were introduced into the regression analysis. (2) A regression equation was obtained which predicts the slurry head loss of 1-inch by 0 coal slurries ranging in volumetric concentration from 20 to 40 percent and line velocities from 1 to 14 feet per second as a function of the square of velocity. The addition of the term for concentration in the regression equation did not contribute significantly c head loss.

Jan 1, 1972

By C. P. Bowie

The Bureau of Mines has been conducting investigations with the view of determining the types of containers best adapted to the stor- age of oil. These investigations have shown that tanks composed wholly of steel give the best results. Where larger containers than it is feasible to build with steel are desired, concrete-lined reservoirs can be recommended for some grades of oil. Practically all such containers in use at present have wooden roofs and this type of construction is here described, although it is the belief of the writer that concrete roofs would be far more satisfactory in every way, and that the difference in cost between a concrete and a wooden roof would, as a rule, in a few years' time, be offset by a saving of oil and in cost of repairs and renewals.

Jan 1, 1918

Develop a full-length-anchored roof bolt that is economical, nontoxic, nonflammable, and non-allergenic. Approach Grout roof bolts with a storable mixture of ultra-fast setting inorganic cement and water. How It Works A loose mixture of dry cement powder, and pinhead-size water droplets encased in waxy globules, are pack-aged in sausage shaped cartridges for storage and use. After the cartridge is inserted Into a drilled hole, the roof bolt is thrust In and rotated to mix the cement and water. The cement hardens in seconds, providing usuable anchoring strengths in minutes. Prior to filling of the sausage shaped cartridges, the microcapsules of water are Intimately mixed with the dry cement. The currently used grouting consists of a mixture of one part water (minimum) with three parts alpha-type gypsum cement and a minor amount of accelerator.

Jan 1, 1978

Pillar design is the first line of defense against rock falls—the greatest single safety hazard faced by underground coal miners in the United States and abroad. To help advance the state of the art in this fundamental mining science, the National Institute for Occupational Safety and Health organized the Second International Workshop on Coal Pillar Mechanics and Design. The workshop was held in Vail, CO, on June 6,1999, in association with the 37th U.S. Rock Mechanics Symposium. The proceedings include 15 papers from leading ground control specialists in the United States, Canada, Australia, the United Kingdom, and the Republic of South Africa. The papers address the entire range of issues associated with coal pillars and have a decidedly practical flavor. Topics include numerical modeling, empirical design formulas based on case histories, field measurements, and post failure mechanics.

Jan 5, 1999

By Paul M. Ambrose

THE ABRASIVES INDUSTRY throughout the world enjoyed a profitable year. With the exception of tripoli, the quantity of each kind of abrasive produced in the United States was greater than for any of the past 5 years and value of each was greater than for many years. Production of silicon carbide both in the United States and in Canada was the largest since 1960. Abrasive machining, which offers great potential for the increased Use of aluminum oxide, contributed to increased industrial productivity. Diamonds from the sea off the coast of South-West Africa attracted wide interest. Much of the production from this source has been gem diamond, and there is little likelihood of significant quantities of industrial diamond from that source. Manufactured diamond from all free-world sources was sold in the United States in 1964.

Jan 1, 1965

By Stephen R. Iverson

The U.S. Bureau of Mines made an economic appraisal of the Buttermilk study area, Inyo County, California in October 1980. Results of surveys indicate no potential for metallic, non-metallic, or energy resources in the area. However, glacial till covering most of the area prevented bedrock examinations by the appraisal teams or earlier prospectors. No mining claims are known to be in the area. INTRODUCTION Present Studies The U.S. Bureau of Mines, Western Field Operations Center, searched county mining claim records and other data available concerning mineral deposits, claims, leases, production, and mining activity in the area. The Bureau conducted field work in October 1980 searching for prospects and claim locations. Fourteen reconnaissance lode and placer samples taken from the area were analyzed for gold, silver, and tungsten; a spectrographic analysis also was run on selected samples.

Jan 1, 1981

"Research on the control of exposure to respirable contaminants in mine atmospheres is conducted in five areas; 1) control of dust generation, 2) dilution, dispersion and collection of dust in mine airways, 3) characterization of dust particles, 4) interaction of dust and lungs, 5) relationship of mine environment, geology, and seam characteristics to dust generation and mobility. The distribution of research findings to the mining industry, to government agencies, and to scientists at other universities is accomplished in several ways.A data bank of respirable dust samples displaying a wide range of characteristics (low volatile, medium volatile, high volatile, silica fireclay, rockdust) has been established by the Center. This data bank is being utilized by Center researchers in a suite of medical, scientific, and engineering tests (FIGURE 26).The Center has honored requests for educational and informational materials from several sources, including MSHA and CANMET who received information on Center generated software and used the Center's expertise in developing a computer program for particle distribution model (DISFIT).The Generic Mineral Technology Center for Respirable Dust has organized two dust conferences on respirable dust, the Coal Mine Dust Conference, held at West VirginiaUniversity, Morgantown, West Virginia from October 8-10, 1984 and Respirable Dust in the Mineral Industries: Health Effects, Characterization and Control, an international symposium on Respirable Dust in the Mineral Industries held at The Pennsylvania State University, University Park, Pennsylvania from October 14-16. 1986. These conferences were co-sponsored by the U.S. Bureau of Mines, Mine Safety and Health Administration, National Institute for Occupational Safety and Health (NIOSH), and the American Conference of Governmental Industrial Hygienists (ACGIH). On August 23-26, 1988, the VIIth International Pnuemoconioses Conference was held in Pittsburgh, Pennsylvania. While not a sponsor of this conference, researchers in the Generic Mineral Technology Center for Respirable Dust had significant participation with sixteen (16) papers presented (see Volume 8 of this series for abstracts and papers). These conferences provided a significant forum for the exchange of ideas on dust research and the interchange of research findings. The proceedings from these conferences are available from NTIS and ACGIH.In sum, significant benefits to mine worker health have resulted and should continue to result from the synergistic scientific, engineering, and medical research in respirable dust (FIGURE 27). As always, an important objective is the rapid dissemination of the results of this research to industry. Video tapes and the Bureau's Technology News series have been a very effective means of USBM technology transfer. Individual no-cost subscriptions to the Technology News series are available from the U. S. Bureau of Mines, Branch of Technology Transfer, 2401 E Street, N.W., Washington, DC, 20241."

Aug 31, 1989

By Ronald S. Conti

This paper describes technology and training that has been identified for underground emergency responders. Historically, underground mine rescue teams have only received training in the course of actual emergencies, or in simulated mine environments, usually on the surface, with placards to identify objects and hazards. Also, while U.S. Federal Regulations require all underground miners to walk escapeways and conduct fie drills every 90 days in a smoke-free environment, this does not fully prepare them for the conditions that will be encountered in real escape situations. Therefore, it is extremely important that miners are provided with adequate technology and that training simulations are conducted in a realistic manner. A series of mine rescue training and mine emergency response development (MERD) exercises, and in-mine smoke training was developed, conducted, and evaluated by state and company teams, and by National Institute For Occupational Safety and Health (NIOSH) personnel. The training exercises were held at NIOSH's Lake Lynn Laboratory (LLL) and operating mines during the past several years. This training resulted in improved technology and training for mine rescue teams, fire brigades, first responders, and miners in general. For example, existing technologies were identified to help responders during exploration and recovery operations. These included various chemical light shapes, strobe lights, light vests, and laser pointers to identify team members. Most of these devices may be used to mark underground areas and certain mine materials. Strobe lights were used for mapping out escapeways and lasers were used to negotiate travel through smoke. Thermal imaging systems allow rescue personnel to see in darkness and through dense smoke, and allows the user to easily locate missing or trapped personnel and heated areas. A hands-free communication system showed potential for enhanced communications between team members, the fresh air base, and command center. A new team lighted-lifeline allows for flexibility in movements of team members during routine tasks and allows them to easily find their fixed position on the lifeline. Of all the technology evaluated by underground personnel, laser lights and lifelines were most beneficial in leading personnel to safety and out of the mine in smoke-filled passageways. A positive-pressure inflatable escape device (IED)/airlock, was used to isolate the "hazardous" environment from fresh air and allow rescue team members to traverse through. An inflatable feed- tube partition that can rapidly block large openings such as underground passageways or tunnels and simultaneously provide a feed-tube for high-expansion foam generators was also deployed during the simulations. These technological advancements have improved the state of readiness for rescue personnel and have increased the chances of survival for all personnel escaping from underground emergencies.

Homans [1950] offered a working definition of group that is useful for this research: "We mean by a group a number of persons who communicate with one another often over a span of time, and who are few enough so that each person is able to communicate with all the others, not at secondhand, through other people, but face-to-face." This chapter begins with a discussion of the group concept in reference to the hypothesized escape groups mentioned earlier. It then moves to an examination of analysis techniques used by the authors. Finally, the subjects themselves are profiled according to their demographic characteristics. The Nature of Groups Warriner [1956] took a realist approach to understanding groups: "(1) the group is just as real as the person, but (2) both are abstract, analytical units, not concrete entities, and (3) the group is understandable and explicable solely in terms of distinctly social processes and factors, not by reference to individual psychology." Warriner's realist position merely holds that "group" occupies a different domain in which it is no more or less concrete than "person." At this group level the unit of analysis will be those relations that indicate social rather than individual behavior. It is possible to investigate these group properties empirically-if a researcher avoids confusing conceptual entities with concrete ones. Most people seem to accept that group attributes must somehow be inferred, but think personal attributes will be directly manifested, requiring little or no interpretation [Snizek 1979]. In other words, nobody would equate physical components of an underground working section with the actual work group, yet social scientists (as well as laypeople) very often confuse real individuals with notions of the person. In actuality, neither groups nor persons are directly disclosed to the senses; both are inferred by experience and observation. One can "see" a group just as clearly as one can "see" a person, given the proper perspective from which to do so. It is necessary, in developing this perspective, to begin with a sound definition of the thing being examined. Besides communication, or more generally, social interaction, Homans [1950] included three other components of group makeup. "Sentiment" is characterized as the feelings people tend to form about one another when they interact often. These feelings include not only friendliness and dislike, but attitudes such as approval or disapproval. A "norm" is an idea, held in common by group members, that specifies how people ought to behave in given circumstances. In lay terms, norms are simply those informal rules individuals abide by in order to get along together in social situations. Finally, "activity" refers to those things persons do with others. In work groups, as an example, many of the activities are cooperative and goal-directed.

Jan 1, 2000

By Shouchen Dun, Zong-Ming Li

Manipulation of hand-held objects in 3D space is a complex task. Understanding how individual digits interact with a hand-held object provides helpful information for hand tool designers, researchers, clinicians, and occupational therapists. At the object-digit interface, the contact mechanics can be represented by three force and three torque components. Six-component force/torque transducers can register all the three forces and three torques at the digit-object interface, and therefore are advantageous in the study of manipulation mechanics. The large number of force and torque signals from multiple force/torque transducers are difficult to interpret and therefore making experimental research of manipulation a challenging task. The purpose of this study was to develop a 3D visualization tool for the investigation of the contact mechanics at the object-digit interfaces during manipulation tasks. Methods A 3D stick-figure hand model was created based on digitized 23 anatomical landmarks of the hand. Five miniature 6-component force/torque transducers (4 × Nano17 for the fingers, 1 × Mini40 for the thumb, ATI Industrial Automation, NC) were used to record force and torque data at the tips of individual digits. Thirty channels of force/torque signals from the transducers were collected by a 16-bit analogue-digital converter (PCI-6031, National Instrument, Austin, TX) installed in a computer. The transducers were mounted on a custom-made rectangular aluminum handle for object manipulation. Coordinate frames were established at each transducer, on the handle, and at the base of the MicroScribe digitizer. To visualize the force vectors at the digit-tips, the coordinates of the hand landmarks in the MicroScribe coordinate frame and the force vectors in local transducer coordinate frames were transformed to a common coordinate frame defined on the handle. One healthy right-handed, male subject participated in the experimental study. During the tests, the participant sat in a chair by a testing table. The forearm was strapped to an arm holder in neutral rotation position. The instrumented handle was fixed on the testing table by a C-clamp through an adapting plate. With the hand of the subject gripped on the instrumental handle, the landmarks of the instrumented handle and the transducers, as well as the anatomical landmarks of the hand were digitized using the MicroScribe digitizer for the purpose of coordinate frame establishment and transformation as described above. The subject performed three different maximum isometric voluntary contraction tasks: (1) grasping, (2) rotating in pronation, and (3) lifting. Results The 3D hand model and representative force vector clusters in a single trial of grasping, rotating, and lifting tasks are shown in Figure 1. Each cluster was formed by displaying all the 3D force vectors during the period of “stabilized” maximum effort in a trial. The magnitude and

Jan 6, 2006