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By Warren E. Morrison

Stimulated by 4 years of continuous economic growth without inflation, demand for energy in the United States reached an alltime high in 1964. Total value of production of goods and services (gross national product--GNP) for the year was $629 billion, an increase of 6.8 percent from 1963. Allowing for price changes based on 1958 dollars, the gain in real terms was 5 percent. In 1964 the Federal Reserve Board Index of Industrial Production stood at 132, a rise of 6.2 percent. With the impetus provided by personal income and corporate tax reductions during the year, aggregate wages, profits, and consumption reached record levels. Even the persistent balance of payments problem improved. Against this background the national consumption of commercial energy increased 4.2 percent. Energy needs continued to be met largely from domestic resources with imports, mainly crude petroleum and refined petroleum products, accounting for but 7 percent of the total. Mineral energy resources, namely gas, coal, and petroleum, contributed 96 percent of the input of energy into the economy during the year. The remaining 4 percent came from hydropower and nuclear power.

Jan 1, 1965

By H. S. Auvil

[Coals of low-volatile rank cannot be coked without admixing large proportions of high-volatile coal in the usual type of byproduct-coke oven, because they expand excessively and exert side thrust, which ruins the oven walls. Some medium-volatile coals also give trouble. Since high-rank coals produce a strong, blocky coke, it is desirable to have the rank as high as practicable, particularly in the manufacture of foundry coke. Accordingly, it has become the practice to mix or blend high-volatile shrinking, coals with as much low-volatile coal as possible and still have a mixture that will not deform the walls or cause difficulty in pushing the coke. Occasionally, the safe limit of low-volatile coal has been exceeded and ovens have been damaged. It is desirable, therefore, to rave a reliable method of determining the expanding tendencies of mixtures before they are charged into the ovens. Furthermore, coal charges somewhat in its properties as mining progresses, and therefore, mixtures found to be safe at one time may cease to be so subsequently, particularly if nearly the maximum allowable percentage of low-volatile coal is being used.]

Jan 1, 1938

By Wm. F. Netzeband

"The mode of ore occurrence and the methods and costs of mining at one of the zinc-lead mines in the Tri-State zinc and lead district, Oklahoma, are presented in this paper for the information of mine operators in other districts.No. 2 mine property was acquired by lease in 1918 after some 30 holes had been drilled and a shaft had been sunk to the 305-foot level by the first lessees. After acquisition of the lease, the present operating company drilled a rich ore body on the 260-foot level and in 1920 started sinking two shafts. Production was begun late in 1921, and the mine has been operated more or less continuously to the present time.The mill has a capacity of 400 tons in 10 hours, the usual length of the mill shift in the district.The geology of Mine No. 2 is very similar to that of Mine No. 13 except that the Cherokee shale is thicker, ranging from 80 to 160 feet, and all the formations are correspondingly deeper, the Short Creek oolite horizon here being at a depth of about 300 feet. The oolite has not been found on this property, but the lime comes in at about the level at which the oolite should appear.The ore deposits of Mine No. 2 occur in the brecciated and bowlder ground above the Short Creek oolite. The main or 260-foot level is about 40 feet above the oolite horizon, and the lower or 300-foot level is immediately above it.The ore deposition is controlled by a zone of shearing and fracturing, and the mineable areas are divided into two distinct runs which have a northwest trend with a lean or practically barren area dividing them. This characteristic has controlled the mining to a large extent, for it enables the mine superintendent to locate the large pillars in lean ore and leave only small pillars in the richer ore. Figure 1 shows the outlines of the ore body and the pillars.The ore on the main level occurs disseminated throughout the jasperoid breccia as patches or lenses in the jasperoid, or cementing massive bowlders of jasperoid breccia and chert. The ore of the lower level is more of the bowlder type than that on the main level and occurs chiefly cementing the bowlders but also with some disseminated ore in the jasperoid breccia.The gangue minerals are jasperoid breccia, chert, and dolomite. Calcite is found in minor quantities. Sphalerite is the principal ore mineral; galena is found only in minor quantities around the edges of the ore body. When galena is encountered in this ore body, the limit of the ore can be expected.The exploration and estimation of ore reserves at Mine No. 2 are similar in many respects to the methods used at Mine No. 1.4After the mine was opened up and the general character of the ore deposit had been determined, drilling operations were concentrated along the trend of the shear zone. Later drilling has proved what appears to be a parallel shear zone or an offset of the zone now being mined."

May 1, 1929

By E. A. Barrett

The U.S. Bureau of Mines (USBM) conducted experiments to determine if training using a latent-image, three-dimensional (3-D) slide simulation exercise improved miners' ability to recognize roof and rib hazards. The effectiveness of this innovative type of classroom training was investigated by measuring workers' performance on a hazard recognition task. The study was unique in that hazard recognition skills were assessed in the workplace using actual coal mine roof and rib hazards. Results showed that training with a latent-image, 3-D slide simulation exercise significantly improved each subject's performance on the in-mine hazard recognition task. Further, the USBM researchers concluded that transfer of learning from the classroom to the workplace occurred.

Jan 1, 2010

By Todd M. Ruff

Researchers at the National Institute for Occupational Safety and Health (NIOSH) are studying methods to prevent workers from being entangled in machinery used at mining operations. An analysis of mining accidents in the United States that resulted in a fatality or permanent disability from 2000 through 2005 showed 438 severe incidents that involved contact with machinery or equipment, an average of 73 per year. Researchers determined that the most common machinery involved in these severe accidents was conveyors. Also, a significant portion of the accidents occurred during machine maintenance and repair. Researchers are focusing on improved methods to prevent unintentional machine startup during maintenance activity and methods to detect workers near moving machine components. One new technology that shows promise for this application is intelligent video. Popular in the surveillance and security industries, these systems use cameras and computerized video analysis techniques to automatically detect the presence of people in preset zones within the camera?s field of view. A preliminary study has been initiated to determine if this technology could reliably detect the presence of workers in hazardous locations near machinery. Possible advantages of the use of this technology include improved detection zone demarcation and improved ability to distinguish between hazardous and non-hazardous proximity, compared to conventional proximity sensor techniques. Initial tests to detect a person near a conveyor system in daylight conditions showed promising results. A description of the technology, test procedures and results, implementation challenges, and future research needs are discussed.

Jan 1, 2008

By Valois R. Shea-Albin

Ground control problems are an important factor affecting safety, production, and efficiency in underground coal mines. A major portion of ground control problems encountered in underground coal mines can be attributed to geologic features in the strata surrounding the extracted coal seam. The U.S. Bureau of Mines has compiled information from numerous sources on the geological features that contribute to ground control problems in underground coal mines. The compilation includes (1) sedimentary features such as paleochannels, crevasse splays, clastic dikes, mold-and-cast structures, concretions, and lithologic factors, and (2) structural features such as folds, fractures, joints, cleat, and faults. The compiled information will aid in identifying the features, predicting their occurrence in advance of mining, and controlling or minimizing roof failure when these features are encountered in an underground coal mine.

Jan 1, 1993

By George W. Healy

The direct retorting of zinc sulfide concentrates in the presence of lime and carbon was examined on a laboratory scale with ten-gram charges of loose mix or fifteen-gram ones of pellets. A slow stream of nitrogen swept through the furnace tube over the boat of reactants, carrying with it the zinc vapor, which condensed on a rolled-up steel sheet near the exit, permitting weight of zinc produced to be obtained after completion of a run. Variables explored were percent of theoretical reagents, temperature, and time. During the runs gas samples were analysed periodically, and the content of CO2, CO and nitrogen were obtained. The quantities of the carbon gases could be calculated because the nitogen flow rate was measured. The gases were also examined for sulfur species, but neither COS nor SO2 could be detected at maximum sensitivity. Zinc recovery increased with excess carbon and lime and with temperature. It ranged from 77% at a ten percent deficiency to 90% at a ten percent excess at 1100°C. Going to 1200°C and theoretical reagents gave 93% recovery. Increasing time from 200 minutes to 300 minutes increased zinc yield by up to 10%. Results from sphalerite and a commercial concentrate from AMAX gave generally similar results. The reaction rate of zinc sulfide as sphalerite and of calcined sphalerite indicated that the latter reacted almost twice as fast, and recovery of zinc was five percent higher. Though the retorting step using sulfide, lime, and carbon proved to be non-polluting, it was feared that on storage the calcium sulfide in the residues would decompose, giving off noxious gases. Consequently the stabilization of the residues by oxidation was essayed. Because of the presence of unreacted zinc sulfide, the first product of oxidation was S02. Reaction of CaS to CaSO4 was incomplete, going from 20% at 800°C to 90% at 1200°C. Thus the non-polluting nature of the process as a whole is in doubt, and its economics are likely to be unfavorable compared to the traditional way of calcining the concentrates, followed by retorting of the oxide with carbon.

Jan 1, 1982

By H. L. Burmeister

This report describes the mining and milling practices used by the Eastern Magnesia Talc Co. at its Johnson, Vt., operation. The report also contains a description of the local geology and all available information on cost and performance data. Since 1925 the mine has produced continuously at an average annual rate of 54,000 tons, and the ratio of ore hoisted to finished product is roughly 2 to 1. Ore is stoped by a combination of shrinkage and sublevel methods. In any 24-hour period the mill produces an average total of 14 grades of finished talc product, 9 by dry grinding and air classification and 5 by wet grinding and flotation methods. The mine operates one shift per day, 5 days per week and the mill operates on a 3-shift, 5-1/2-day-per-week basis. Operating costs for 1958, on a percentage basis, were mining, 22.34; milling, 54.77; ore haulage, 2.89; and all other, 20.00 percent.

Jan 1, 1963

By G. S. Rice

To those concerned in attaining greater safety to life and incidentally to property in coal mining, the meeting of representatives of the national mine safety research organiza¬ tions of the principal coal-producing countries, which was called by the Safety in Mines Research Board of Great Britain at its experimental station near Buxton, should have deep significance. It is notable, first, because it meant the friendly cooperation of countries not many years ago engaged on either side in the great World War; and second, because of the remarkable degree of agreement in the essential fundamental factors and methods of attaining greater safety in coal mines when it is considered that the questions were approached by different paths and that the applications dealt with widely differing natural conditions and national points of view. Varying views, of course, were held as to the relative importance of certain factors, but the differences were of detail rather than of principle. When the meeting adjourned it was unanimously agreed that such meetings should be continued annually and that the greatest benefit was to be derived by close cooperation in the exchange of data. Belgium, France, Germany, Great Britain, and the United States were represented by one or several members of the respective national research organization. It is of interest to note that this research work in Belgium, France, and Germany is supported directly by na¬ tional organizations of mine operators or owners but placed under a scientist appointed by the respective Government, thus giving the work official standing. In Great Britain the work is carried on by a Government board, consisting of persons connected with the coal¬ mining industry or in mining research, appointed by the Secretary for Mines, to direct the work of research of the Mines Department. It does not, however, come under its inspection service. Its work is supported by a penny-a-ton tax on output of coal. In the United States the mine-safety research work is directly supported by the Federal Government.

Dec 1, 1932

By L. C. IlsLey

The cool drills that have received the approved of the Bureau of Mines may be divided into three general classes: (1) Hand drills, small drills that are held in the hands or supported against the body while in use; (2) post drills, drills that are too heavy or powerful for hand operation and therefore require some mechanical mounting when in use; and (3) drilling machines. Besides these three classes, drilling equipment has been incorporated in the design n of a number of permissible coal-cutting machines, but such drills are considered an integral part of the cutting machine and are not given separate approval. The hand drills have been described in Report of Investigations 3363, which is cite of several papers that have been published dealing with miscellaneous types of permissible motor-driven mind equipment not covered in bulletins. The present paper describes post drills and drilling machines approved by the Bureau of Mines up to July 1, 1937.

Jan 1, 1938

Minerals are vital to any industrialized civilization. Annually, the United States uses more than 4 billion tons of new mineral materials, or about 40,000 pounds per person-about half being mineral fuels and the other half being metals and nonmetallics. Stable and economic domestic mining, mineral, metal, and mineral reclamation industries are essential to the economy. The value of United States energy and processed materials of mineral origin exceeds $200 billion annually. Although a number of minerals are imported, especially some designated as "strategic and critical," most U.S. mineral supplies are derived from the domestic mines and processing facilities that you will be seeing, reading about, and visiting as you use this visitor guide. We hope you enjoy your experiences. This pamphlet, a guide to mining and mineral operations that may be observed or visited and some other points of interest relating to minerals, is intended to aid tourists and students who are interested in mining. Some may wish to study our Nation's romantic past; others may plan to enter the minerals industry as a career; still others may have a primary interest in conservation practices. The pamphlet is also intended to aid State and local officials, Chambers of Commerce, and mining firms in answering some of the many questions of tourists and students.

Jan 1, 1976

By L. C. IlsLey

[The cool drills that have received the approval of the Bureau of Mines may be divided into three general classes: (1) Hand drills, small drills that are held in the hands or supported against the body while in use; (2) post drills, drills that are too heavy or powerful for hand operation and therefore require some mechanical mounting when in use; and. (3) drilling machines. Besides these three classes, drilling equipment has been incorporated in the design n of a number of permissible coal-cutting machines, but such drills are considered an integral part of the cutting machine and are not given separate approval. The hand drills have been described in Report of Investigations 3303, which is cite of several papers that have been published dealing with miscellaneous types of permissible motor-driven mind equipment not covered in bulletins. The present paper describes post drills and drilling machines approved by the Bureau of Mines up to July 1, 1937.]

Jan 1, 1938

By Juel H. Stears

The bureau of Mines analyzed data from 47 coal mine roof-fall resupport accidents that occurred from 1966 through 1974 to identify critical hazards .and problems. These accidents resulted in 62 injuries or fatalities. It was concluded that the majority of the accidents might have been prevented by observance of recommended practices and use of available technology such as setting temporary supports, adequate roof testing, etc. Additional work is needed in the following problem areas where present technology is inadequate: (1) warning of impending roof falls shortly before they occur, (2) better methods of detecting unsafe roof and ribs, (3) providing access to and temporary support of high roofs for testing and bolting, (4) reducing the noise level of stopers, (7) developing temporary roof support; that have greater stability and can be remotely installed, and (6) reducing the number of roof falls through better permanent support.

Jan 1, 1976

By Harry R. Johnson

Domestic expenditures by the U.S. petroleum industry have exhibited distinctive shifts in emphasis over the past 20 years. From the end of World War II to 1955, expenditures for all phases of the industry expanded. Although over one-half of all expenditures were for production, the relative emphasis was changed after 1956-58 from production toward processing and marketing. The period 1967-69 marked the beginning of a return to emphasis on exploration and production. These trends in expenditure patterns are logical and rational when related to domestic and international economic conditions and to the widespread application of improved production technology. As the immense job of developing the oil resources of Alaska and other regions begins, the petroleum industry will continue to turn to external sources for working capital. Long-term debt will probably be the principal method of external financing through 1970, but a definite shift toward new common and preferred stocks will be made. Higher product prices may be sought by the petroleum industry, but the economics of crude-oil production, changes in the tax structure, and possible changes in the oil imports control program make the price structure of crude oil and crude-oil products unpredictable at the present time.

Jan 1, 1970

By C. L. Karr

U.S. Bureau of Mines (USBM) research has shown that fuzzy logic and genetic algorithms (GA's) have great potential for industrial process control. A technique has been developed by the USBM in which GA's are used to substantially reduce the time needed to design fuzzy logic controllers (FLC's).This technique shows promise as an efficient, robust approach to developing control systems. The research described in this report is twofold. First, the basic approach to developing an FLC using GA's is presented. The GA-designed FLC is developed for a specific physical system, a pH titration system. Second, empirical results are presented in which variations in the FLC implementation are compared. Specifically, the effects of altering five aspects of the pH FLC are considered: (1) membership function form, (2) number of fuzzy classes, (3) the center-of-area method, (4) implication operator, and (5) fuzzy rule form. Results indicate that (1) the technique in which GA's are used to design FLC's is effective, and (2) when this technique is used, variations in FLC implementation have little effect on FLC performance in a chosen control problem.

Jan 1, 2010

By L. A. Morley

Volume III of the final report examines the indication versus interruption procedures used on motion-drive power equipment, with emphasis on surface excavators. The report begins with a review of the electromechanical acid conversion used with the Ward-Leonard control system. Protection criteria for the drive-system components are then discussed. Fault sources and fault calculations for both the ac supply source and dc power loop are introduced to assist in discussing indication and interruption procedures. The subject is then expanded to examine the dynamic process of the machine and determine the effects of fault current and position of the machine to allow for an orderly shutdown. With this analysis, possible indication an interruption procedures are given for the four-quadrant duty cycle of excavators. The report concludes by introducing other mining operations that utilize similar motion-drive systems and also static (solid-state) drives and recommends further research in these areas, as well as a more detailed examination of the dynamic fault analysis for excavators.

Jan 1, 1982

By Anderson Dana

THIS PAPER describing methods and costs of mining and preparing gravel and sand for market at the Port Jefferson plant of the Seaboard Sand and Gravel Corporation, is one of a series of articles on gravel and sand mining, prepared for and published by the U. S. Bureau of Mines, which is designed to disseminate technical information regarding the methods used. The cost tabulations represent operating expenditures only and not total costs, It is recognized that publication of total costs might in many instances cause embarrassment to individual producers, as well as to the industry as a whole. On the other hand, operating costs are essential to the technical [ ]

Jan 1, 1932

By John C. Machisak

THIS CHAPTER of the Minerals Yearbook (volume III) contains overall injury experience and employment data at bituminous-coal, lignite, and anthracite mines, coking plants, metal and nonmetal mines, metallurgical plants, and stone quarries in the United States for the calendar year 1956. Volume I of the Yearbook includes injury experiences and related employment data in the metal, nonmetal, and quarrying industries, and in the milling operations connected with the mining of those commodities. Volume II contains the injury and related employment experience of the coal mining, coking, and oil and gas industries. Reporting is voluntary on the surveys conducted by the Bureau of Mines to collect injury and employment data in the mineral industries, except in the coal-mining industry, where operators are required by Federal law to furnish the information requested.

Jan 1, 1958

By David E. Fogelson

One model each of three different makes of portable displacement seismographs was calibrated on a shaking table capable of 5,000 pounds of force, Calibration tests were conducted in the frequency range of 5 to 200 c.p,s, and in the amplitude range of 0,002 to 0.05 inch peak-to-peak, The seismographs were tested under two mounting conditions: (1) The feet of the instrument were bolted to the shaking table, and (2) the feet were resting on emery cloth affixed to the table, The results of these tests show that, in the frequency range of 5 to 40 c.p,s, and for vibration levels less than 0.2 g, the magnification for all three instruments is constant with input level but varies slightly with frequency. For vibration levels greater than 0.4 g. and for frequencies greater than 40 c.p.s., the magnification of all three instruments shows large variations with frequency and amplitude of table motion.

Jan 1, 1962

By George K. Schenck

This Bureau of Mines publication describes and evaluates a Standard Industrial Classification (SIC) based end-use data system for minerals that is designed to link the demand for minerals to economic activity in commercial uses. The new data system is two-dimensional. The first dimension of technical product classes (TPC's) measures the consumption of minerals in major primary intermediate products. The second dimension measures the consumption of these TPC's in SIC end-use sectors in sufficient detail to identify the major determinants of demand for each TPC. Intercomodity comparisons are achieved at the level of SIC two-digit major groups. The methodology was developed so that all available sources of information from Government and industry can be utilized at minimum cost. This information will be supplemented with additional data to be obtained by modifying existing Bureau of Mines canvasses so as to elicit additional quantitative responses from mineral producers. The new data system is expected to improve significantly the ability to forecast demand for minerals, and provide an information base that would, for the first time ever, permit resolution of such questions as trends in substitution among materials and the intensity-of-use of materials in end-use sectors. For the 42 TPC?s identified in the report, data are available for the new system from current sources or, except for three TPC?s that require new canvasses, can be obtained by modification of existing Bureau canvasses.

Jan 1, 1982