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By O. C. Blade

In its general study of crude petroleum, the Bureau of Mines has published several reports that include analyses of samples of crude petroleum from Oklahoma fields3/. This report discusses briefly the properties of crude oil samples collects in come of the major producing Yields in the State. ACKNOWLEDGMENTS This investigation was conducted by the Bureau of Mines in cooperation with the State of Oklahoma. The study was via e under the general supervision of R. A Cattell, chief engineer, petroleum and Natural-Gas Division, Bureau of Mines, Whishington, D. C., and N. A. C. Pith, supervising engineer, Petroleum Experiment Station, Bureau of Mines, Bartlesville, Okla., and. Under the direct supervision of Ludwig Schmidt, senior petroleum engineer, Bureau of Mines, Bartlesville, Okla.

Jan 1, 1939

By P. Falcão Neves

A detailed analysis of the geomechanical behaviour in rock cutting with a diamond saw is provided to obtain a better understanding of the mechanisms involved in the process. The energy of elastic deformation (before failure) and plastic deformation (post failure) was determined in uniaxial compression tests as well as the energy consumed per unit volume in the cutting process. The test samples are White and Ruivina marbles from Borba - Vila Viçosa in Portugal. Correlations between total deformation specific energy and cutting specific energy, normal and tangential forces and diamond indentation are analysed, and some conclusions are presented.

Jan 1, 2012

By O. C. Blade

[In its general study of crude petroleum, tic Bureau of Mines has published several reports that include analyses of samples of crude petroleum from Oklahoma fields3/. This report discusses briefly the properties of crude oil samples collects in come of the producing fields in the State ACKNOWLEDGMENTS This investigation was conducted by the Bureau of Mines in cooperation with the State of Oklahoma. No study was made under the general supervision of R. A Cattell, chief engineer, petroleum and Natural-Gas Division, Bureau of Mines Washington, D. C., and N. A. C. Smith, supervising engineer, Experiment Station, Bureau of Mines, Bartlesville, Okla., and under the direct supervision of Ludwig Schmidt senior petroleum engineer Bureau of Mines, Bartlesville, Okla.]

Jan 1, 1939

By R. W. Stahl

Burning coal-mine refuse banks were surveyed in 15 States. The following characteristics were tabulated for 495 hanks: County; name, population, and distance of nearest town; size and status of bank; status and stage of fire; and topography. Ways of controlling fires were reviewed, the compacting and sealing method proving most satisfactory. Means for preventing refuse-bank fires by proper construction of banks are described.

Jan 1, 1964

By J. T. Chen, S. Winkler, M. J. Worswick, O. Orlov

This paper presents a review of research conducted at the University of Waterloo concerned with the application of aluminum alloy sheet and tube in automotive structures and body panels. The research has focussed on formability prediction and results using a range of damage-based formulations. These models include continuum-level damage approaches and, more recently, a so-called percolation damage approach intended to capture microstructural heterogeneity effects on damage development. This paper presents applications of these damage approaches to simulate formability of experiments considering stretch flange panels. The experiments consider drawbead effects associated with the bend/unbend deformation as the material flows through the drawbead. Recent work on simulating in situ X-ray tomography experiments that capture damage evolution during tensile deformation will also be reviewed.

Jan 1, 2006

The Bureau of Mines found sulfur hexafluoride (SF6), released from a lecture bottle, to be an ideal gaseous tracer for studying mine ventilation systems. Air samples were collected in glass syringes and analyzed by electron-capture gas chromatography. In these studies, the lower limit of detection was about I part per billion by volume (ppb) of SF6 per part of air. Experiments conducted in a Pennsylvania limestone mine showed this technique useful in evaluating the effectiveness of auxiliary fans, measuring low flow velocities, probing the air circulating near a working face region where ventilation appeared to be poor, and estimating volumetric flow rates in airways of large cross-sectional area and having low flow velocities. This technique was also used in a western vein-type metal mine to measure the amount of return air being recirculated into the intake air due to leakage through old stoped areas.

Jan 1, 1974

By E. B. Olds

This paper describes the methods and costs of deepening the 3-compartment underground shaft in the Hooper Tunnel adit at the Bunker Hill & Sullivan Mining and Concentrating Company Crescent mine in the Coeur d'Alene mining region, 7 miles east of Kellogg, Shoshone County, Idaho. The work was done with the aid of a Defense Minerals Exploration Administration contract (No. Idm-E493, Docket No. DMEA-2764). Preparation for deepening the shaft was begun March 26, 1953, and sinking was completed May 27, 1954. The shaft, bottomed at 1,275.5 feet in 1939, was deepened to 3,276 feet, using mechanical mucking and intermediate pockets. A total of 50,349 man-hours was required to complete the work of sinking 2,000.5 feet, cutting 7 pump stations, and driving 2 pocket raises. The rate of advance was 7.1 feet of shaft per operating day, or 8.4 feet per day of actual sinking. The total direct cost for sinking was $205.20 per foot.

Jan 1, 1957

The Bulli Seam, New South Wales, comprises medium to low volatile bituminous coal, generally of coking quality. It is worked over an area embracing 300 square miles.Variations in several factors are found.1. The seam is somewhat disturbed and dissected by various structural features.2. This structure, and present topography, have resulted in depths of cover from very shallow to approaching 2,000 ft in the presently worked areas.3. Wide variations of seam thickness occur.4. Gradations of rank occur from place to place.5. Variations in seam gas content and wide variations in seam gas composition are experienced.6. Variations in coal strength occur.These factors may contribute to the occurrence of stress and gas phenomena in mining exploitation.INTRODUCTIONThe Bulli Seam, the most extensively worked seam in Australia, is the uppermost seam of the Illawarra Coal Measures, which comprise the southern portion of the Sydney Coal Basin. Generally, the rank of the seam and its assemblage of types make it ideal for the production of hard metallurgical coke. The thickness and relatively flat dips render the seam suited to mechanized bord and pillar mining, and this method is used almost without exception. At the north-eastern corner of the field, stress and gas phenomena have occurred during mining.Various data have been assembled on physical, chemical and geological conditions of the seam which may influence the occurrence of stress and gas phenomena. This material is presented in an attempt to explain the location of such phenomena to date, and to enable variations in conditions to be considered when future possibilities are being assessed.

Jan 1, 1963

By Charles C. Boley

High-volatile A bituminous coal from the Allen mine, Las Animas County, Colo., blended with char produced from the same coal yielded accept-able metallurgical coke in a 500-lb movable-wall test oven. Nineteen experimental runs were carried out using several concentration levels of two different chars, 5.6 and 19.6 percent volatile matter, produced by entrainment carbonization of the base coal. With the higher-volatile char, an acceptable coke was produced at a 22.5-percent concentration; the lower-volatile char did not produce an acceptable coke at the concentrations investigated.

Jan 1, 1972

By J. N. Van der Merwe

In the process of pillar extraction, pillars are seldom if ever extracted completely. The pillar remnants, or snooks, play an important role in the extraction process. At the working face, they need to be stable to provide a measure of support in the immediate area. Further back, they have to fail in a controlled manner to prevent undue load build-up on the pillars that have not yet been extracted. The stability condition at the working area is the result of interaction between the stability of the pillar and that of the roof rock. It is shown that the primary mode of roof layer failure is by bending induced tension. Direct tension can be excluded in most practical conditions, and only in exceptional cases will the first failure be in shear mode. Panel spans required to cause the first goaf to be formed, predicted using analytical considerations, are of the same order as has been observed in practice. Once the first goaf has formed, the horizontal stress is reduced and failure will occur at more frequent intervals. It is shown that bending induced tension is the most likely mode of failure in an unjointed roof layer. In roof layers with a high frequency of weak or uncemented jointing, failure can be expected to occur at spans equal to the joint spacing. In this context, failure will occur at the smallest of the spans required to induce tensile roof failure and the joint spacing. A fundamental procedure to evaluate the likely roof layer failure in a stacked beam system is developed. This can to be used to estimate the loading condition on snooks. It is shown that snooks assist in stabilizing the immediate roof beam. The sizes and positions of the snooks relative to the position of the next pillar to be stooped, control the magnitude of the contribution to stability. The further the snook is from the next pillar, and the larger it is, the greater the contribution to the stability of the immediate roof. Under the condition of loading by the immediate, continuous roof beam, the position and size of a single snook controls the load acting on it. The closer it is to the nearest solid, provided that the roof overhang extends beyond the snook, the greater the load on it. However, once the immediate roof beam fails, the loading conditions change. The snook is then loaded by the tributary area load. A procedure is developed to assess the condition of snooks for different situations. Using the fundamental considerations developed in this paper, snooks can be designed to be stable during the active mining phase in their immediate vicinity, but to fail once the next line of pillars has been extracted.

Jan 1, 2005

By J. P. Kennedy, O. A. Bascur

Large metallurgical complexes have more data than a small city and these data change as internal and external conditions evolve. Staffing turnover hinders experienced-based decisions especially with simple tools like spreadsheets. Lack of current information can contribute to decisions that result in significant deterioration in the quality of operation. Timely, unified information from sophisticated analyses presented to the broadest possible reach will improve operation. The major innovation is the addition of the web browser to the suite of software people will use with no training – the other two are spreadsheets and graphical presentations – and the consistent organization and transformation of the real time data to support broad access. This paper describes the data transformations and presentation methods necessary for a Web view, especially the special needs of real time data and analysis required for active operations decision-making. Many people inside and outside the complex, not just operators, need timely information that is abstracted, aggregated, organized and unified. Unification and aggregation of real time data presented via the Web opens a new paradigm for collaboration. The analysis tools are as important as the data. These rule-based tools add significantly to the operations database in the form of results stored for viewing with plant data. Mining and metallurgical plants already use many sophisticated analysis tools such as predictive maintenance policies based on statistical analysis vibration analysis, and oil and lube analysis for critical equipment. These add real time events, similar to an alarm package, and unified production information to the operational database. Simple models are used on line to create key indices that provide a real time indication of performance. Key indices include metrics for losses due to plant availability, performance efficiency, and overall process equipment effectiveness. These additional data in the operations database are used for early fault detection, increased production, better quality, higher availability of equipment and faster detection of process bottlenecks. An important feature is the ability for people to create their own key indices and store the results for use by anyone in the plant historian, but accessible by a browser. Keywords: plant information, principle components analysis, data reconciliation, gross error estimation, Internet, Word Wide Web

Jan 1, 2002

By W. J. Mahoney

A good quality assurance program at a coal mine or power plant is accurate, timely and consistent. The quality analysis is accurate due to a complete sampling of the coal stream loaded into the unit train. The sample analysis is accurate because standardized testing procedures are applied. Once an analysis is completed, the results must be communicated to the electric utility in a timely manner. The electric utility needs the results to better manage the coal inventory at its power plants. A quality assurance program can also help a mine deliver a consistent product to a utility's power plants. The importance of accuracy, timeliness and consistency are based on major changes that are taking place in the electric utility industry.

Jan 1, 1994

A simple and cost effective technique to increase fragmentation and burden velocities without making major modification to the overall blast design is with ALTERNATE VELOCITY LOADING OR BOOSTERING OF ANFO. The technique requires the placement of a cartridge or slug of explosive, having higher density and detonation velocity than ANFO, every few feet in an ANFO column. The greater the difference in density and detonation velocity of the Alternate Velocity Load to ANFO, the more pronounced are the results. Emulsions were selected as the Alternate Velocity test explosives because they detonate closer to ideal conditions than most other commercial explosives.

Jan 1, 1989

By A. Adu-Acheampong

The Mid-Tennessee Zinc (MTZ) mines, comprised of the Gordonsville, Elmwood, and Cumberland sites, last operated 4 years ago and are undergoing rehabilitation to begin production in 2008. The mines utilize a random room-and-pillar mining method that results in complex ventilation networks. Upon decommissioning, the mechanical ventilation units were removed and disposed of and several shafts sealed. In an effort to re-open the mines and operate in compliance with imminent Mine Safety Health and Administration (MSHA) diesel particulate matter (DPM) regulatory limits of 160TC µg/m3, a new ventilation system was required. The new ventilation system was developed primarily based on the diesel equipment required to meet production. Particular emphasis was placed on the DPM, diesel equipment utilization, main fan sizing, and fan locations to enable the mines to meet MSHA?s ventilation requirements in a cost efficient manner.

Jan 1, 2009

Interest in industrial minerals in recent years has increased to such an extent that it has taken them into the mainstream of the Australian mineral industry. Notwithstanding that time series data on the values of production, exports, and imports show that industrial minerals are overshadowed by metals and energy minerals, their contribution to the national economy is important and more significant than would seem to be indicated by the statistics. Whereas the ex mine value of metals generally includes some processing (at least to a concentrate stage), most industrial minerals are valued at little more than their extraction cost, in addition to which such costs are generally low because most industrial minerals are exploited in low-cost surface operations. Consequently, values of mine production of metals and industrial minerals are not strictly comparable in that values of mine production of metals tend to be overstated Short term growth of the industrial minerals sector is assured because of several new projects already commissioned but not yet reflected in the statistics. Longer term growth is also assured, based on various other major projects that are likely to come on stream in the early to mid 1990s.

Jan 1, 1989

By George A. Savanick

The objective of this research is to develop a method for measuring the tensile strength at the interface between minerals in rock. These measurements reflect the strength of the attractive forces operating at crystalline interfaces in rock. Since these forces act in opposition to the forces set up in various rock fragmentation processes, measuring their strength may help in designing more efficient methods of rock fragmentation. The method developed for measuring the strength of intergranular adhesion in rock involves separating a bicrystal from the rock and determining the tensile strength at its solid-solid interface. This technique has been successfully applied to the study of quartz-feldspar interfaces separated from massive pegmatites, graphic granite, and the Rockville granite, yielding average tensile strengths of 5.86, 8.62, and 10.65 meganewtons per meter squared (MN/m2) (850, 1,250, and 1,524 psi, respectively). The data this technique provides indicate that the members of these bicrystals are strongly adherent. Examirtation of bicrystals broken at the crystalline interfaces indicates that the bonds responsible for this adhesion operate over only a portion of the interfacial area. This work conclusively demonstrates that tensile strength tests can be conducted on small selected areas; for example, grain boundaries in rock. The small-scale zones of strength or weakness determined in this way can be related to the overall strength of the rock.

Jan 1, 1972

Uranium ore at Sleisbeck, N.T., occurs as lenticular bodies associated with zones of bleached carbonized schists lying between walls of closely folded quartzite. The ore consists mainly of uranium micas with Borne pitchblende.INTRODUCTIONThe Sleisbeck uranium prospect is about 70 miles E. of Pine Creek, and 160 miles S.E. of Darwin (Fig. 1). The prospect consists of a well-defined, E.-W. trending line of hills, about I! miles long. The line is composed of 3 major hills called the Eastern, Central and Western hills, with minor interconnecting hills and outcrops (Fig. 2).

Jan 1, 1955

By D. Leppert

Mr. Garrett brings up several interesting points with respect to the proposed API specification for "nontreated bentonite." However, although not explicitly stated, these specifications are being written based strictly on bentonites from the Wyoming/South Dakota area. Other sodium bentonites may be suitable for use as drill mud but will be unacceptable since the specifications are designed for Wyoming bentonites. Regardless of the API's intent that its specifications are intended only as guidelines, they are generally adhered to on an international basis and, for practical purposes, might as well be chiseled in stone. Estes (1986) notes that the quality of bentonite available from Wyoming producers has steadily declined since the early 1960's. The plastic viscosity: yield point (PV:YP) ratio was included in the current API 13A specification primarily to prevent excessive polymer treatment of lower quality bentonites to make drill mud. However, with development of polymers designed to control YP, this specification cannot ensure that only high-quality bentonites are used for drill mud. Nor will the new specifications for untreated bentonites. Other sodium bentonites are available. Bentonite produced in southeast Oregon demonstrates superior performance characteristics without addition of polymer or other chemicals. However, the exceptionally high purity of these deposits leads to a relatively high YP:PV ratio since the naturally high YP probably results from the higher purity and smaller particle size of this bentonite (Rath, 1986 and personal communication). These bentonites typically have a smectite component exceeding 90% (Rath, 1985), compared with 70% to 75% smectite for typical Wyoming bentonites, as determined by X¬ray diffraction and tests for colloid content. As evident from the accompanying table, the untreated Oregon bentonite has excellent rheological properties, though different from Wyoming bentonites due to the high purity. Additionally, this bentonite reacts well with polymers typically used in the oil industry, making it eminently suitable for use in a low-solids mud system. The extremely low grit content, less that 0.5% on a 75 mm (200-mesh) wet sieve, greatly exceeds the standards set for Wyoming bentonite. Optimum rheological properties are obtained at a higher moisture content than Wyoming bentonites. At 10% moisture, API 13A maximum, the clay is overdried, again reflecting the high smectite content. In summary, the specifications proposed by the API Task Group will ensure that only Wyoming producers can supply "nontreated" bentonite to the oilfield since specifications are

Jan 1, 1989

By Peter de Bakker

The objective of this contract was to develop a simple, reliable, economical, remote-control roof bolting module for installation of mechanical and resin bolts. It was to be capable of placing longer than seam height bolts, up to 10 ft lengths, from a seam height of 36 to 72 in., while keeping the operator under supported roof. The resulting machine, called REM-Bolter, is a low profile unit that utilizes Foster-Miller Flexible Shaft Roof Drill, a Bendix Roof Bolt Inserter and a newly designed. Roof Bolt Lifter/Torquer. Every effort was made to strike a compromise between complete automation and complete manual control. In a controlled laboratory environment the REM-Bolter remotely installed 1000 bolts. Subsequently the machine was tested in an operating coal mine where 500 holes were drilled (and an equal number of bolts were installed) remotely, over a 4 month period. The results of all tests Live shown that the operator of a machine of this kind can quickly, and repeatedly, install rootbolts remotely from his operator compartment some 8 ft away from the drilling/bolting action. The report includes recommendations for improvements to the present REM-Bolter design that would translate the present test bed into a second generation test bed and a potential first generation production unit.

Jan 1, 1983

By M. N. H. Khan

CSIRO has been experimenting with supersonic flows as a method of rapidly quenching metallic vapours. Cooling rates above 106 °C/s have been achieved. The supersonic flow conditions are achieved by adiabatic expansion of the vapour through a Laval nozzle into a vacuum chamber. This paper will describe the basic physics of the process, outlining computer fluid dynamic (CFD) modelling of flow in the nozzle, the effects of different flow conditions on the condensation process and discuss the practical design issues associated with operating supersonic nozzles. Results obtained from a CFD model of the nozzle, which compared two methods of incorporating condensation, showed that inclusion of condensation substantially changes the conditions in the nozzle. Most noticeably, the effect of condensation produces a region in the nozzle where the temperature remains almost constant.

Jan 1, 2006