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By P. G. Barnard

The Nation's steel industry is largely dependent on shipments of manganese from foreign sources for steel production. An adequate substitute for the manganese requirements of our present steel technology would improve our national self-sufficiency and also contribute substantially to the conservation of our manganese resources. As each of these objectives is a major interest of the Bureau of Mines, possible substitutes for manganese in steel were investigated. Titanium was selected as the most promising substitute because the published results of several investigations indicate that titanium would perform the most obvious function of the manganese in steel: The elimination of iron sulfide and its deleterious effects. The investigation involved extending the published data on titanium additions in steel to provide enough information for an accurate evaluation of the practical value of the substitute. Therefore, quantitative data were obtained on the partition of sulfur and carbon between iron and relatively small titanium additions.

Jan 1, 1962

By J. G. Croeni

The titanium-iridium alloy system was investigated to determine whether alloys of this system would merit further development as control-rod material for nuclear reactors. A study was made to determine the titanium-iridium phase diagram by using melting-point, thermal analyses, X-ray diffraction, dilatometric, electrical resistivity, and metallographic techniques. The titanium-iridium alloy system was investigated between 500° and 2,400° C. Results indicate the formation of two intermetallic compounds, Ti3Ir rind TiIr3, and one intermediate solid solution centered about the 50 atomic percent iridium composition. A eutectic reaction occurs at 1,475° C, and 19 atomic percent iridium. The Ti3Ir decomposes peritectically at 1,520° C. The intermediate solid solution exhibits a maxima of 2,140° C. at 50 atomic percent iridium. This phase is also believed to undergo an order-disorder transformation at 1,750° C. Another eutectic reaction takes place at 2,000" C. and 60 atomic percent iridium. The compound TiIr3 formed at 75 atomic percent iridium decomposes peritectically at 2,115° C. Further increases in iridium content result in the formation of an iridium-rich terminal solid solution. Information obtained below 900° C. in titanium-rich alloys indicates that iridium acts as a beta stabilizer in titanium, and the authors believe that a eutectoid decomposition of beta-titanium occurs near 500° C. and 10 atomic percent iridium.

Jan 1, 1962

By H. E. Powell

Because of increasing consumption of high-and super-duty refractories, the Bureau is studying the feasibility of beneficiating submarginal and marginal clays. Diverse mineral dressing tests were used to beneficiate samples from the east-central Missouri fire clay district. Standard ASTM tests were used to determine refractory properties of both crude and beneficiated clay samples. Marginal and submarginal clays containing impurities were effectively beneficiated by both wet-cyclone and wet-table treatment, but the wet-cyclone treatment was cheaper. Ion-exchange resins in the hydrogen form will probably prove more effective in removing potassium, the only alkali in Missouri fire clays to be a problem. Resins with greater cross linkage are more effective than resins with less. Roasting the crude clays before removing alkalis by chemical leaching was ineffective. By applying ultrasonic energy at a frequency of 10 to 25 kilocycles to aqueous suspensions of the clays, subsequent ion-exchange extraction of potassium was slightly improved. Higher frequency ranges did not help.

Jan 1, 1963

By S. D. Maksimovic

The Bureau of Mines identified and evaluated major sources of quartz dust during overburden drilling at a surface coal mine, The relative contribution of each source to the total dust hazard was estimated, using personal gravimetric and instantaneous dust-sampling devices. No attempt was made to determine actual dust generation rates. The major sources of dust at the drill rig during dry drilling opera-tions were the collector dump, drill shroud leakage, and drill stem seal leakage, These sources contributed 90 pct of the respirable dust and 89 pet of the respirable quartz dust generated during drilling, The collector dump cycle (21.6 pct of total drilling time) accounted for 38 pct of the respirable dust and 41 pct of the respirable quartz dust, with peak dust concentrations reaching 68 mg/m3. Shroud and drill stem leakage contributed 28 and 24 pct of the respirable dust and 32 and 16 pct of the respirable quartz dust, respectively. A dragline and second drill rig contributed the remaining 10 pct of dust and 11 pct of quartz dust. Gravimetric dust samples collected inside the drill cab and outside, near the cab door, averaged 1.65 and 1.43 mg/m3, respectively, with 6 pct respirable quartz.

Jan 1, 1985

By David R. Hanson

Experimental work performed by the Bureau of Mines in a laboratory environment has shown that the formation of failure zones within certain rock types is accompanied by the emission of significant amounts of radiofrequency (RF) electromagnetic (EM) energy. This radiation was detected using nonresonant, "electrically short," broad-band antennas. Rock types for which emission was observed include granite, quartzite, and taconite; sandstone and marble did not emit measurable radiation. Amplitude spectra of the radiation showed the energy to be concentrated between 10 and 40 kilohertz. These data indicate that emission is directional, but this has not yet been proven. In addition, amplitude of RF emission increases with increasing crack size. Since emission was observed only for brittle quartz-bearing rocks, it appears the formation of piezoelectric fields is a necessary condition for RF radiation. Plausible mechanisms for emission include rapid decay of piezoelectric fields accompanying the sudden stress release at failure and/or the acceleration of an "exoelectron plasma" through the intense local piezoelectric fields. Since emission appears to increase with the scale of failure, and since antennas do not need to be coupled directly to rock surfaces as with conventional geophones, the possibility of developing a portable system to monitor seismically active areas exists.

Jan 1, 1981

By Kenneth H. Johnston

Information and data necessary for research on improving methods of oil recovery from low-permeability reservoirs and for comparison and evaluation of performance of such reservoirs with those producing from more permeable sands were obtained. Core analyses, well logs, production tests, well stimulation techniques, primary and secondary production records, and data on two water-flood projects were examined for wells producing from the Bartlesville sand, West Avant field, Osage County, Okla. Overall recovery from the study area was generally poor with only 9.0 percent of the pore volume recovered to January 1, 1968. Larger fracture treatments (8,000 to 12,000 gal) could have resulted in an increase in primary oil recovery. Secondary recovery by water-flooding accounted for only 1.9 percent of the pore volume because of the inability to control the large volume of injection fluid that escaped from the flood patterns and the excessive volumes of water produced with the oil. Future waterflood development in other low-permeability reservoirs should include the drilling of new input wells, use of injectivity surveys to locate possible natural fracture systems, or zones of high permeability, and control of injection fluids by altering flood patterns and/or plugging of the more permeable zones.

Jan 1, 1968

By James H. Scott

A technique of seismic refraction data analysis has been developed in which a digital computer is used to generate a two-dimensional model representing a layered-earth depth interpretation. Travel times are picked on seismic records by the human interpreter. These times, together with shot point and geophone locations and refraction layer control information, are submitted to the computer on punched cards. A first approximation delineation of each refraction horizon is obtained by a computer adaptation of the delay-time method. The approximation is then tested and improved by the computer through the use of a ray-tracing procedure in which ray travel times computed for the model are compared against field-measured travel times. The model is subsequently adjusted in an iterative manner so as to minimize the discrepancy between computed and measured travel times. The Fortran program is listed in the appendix of the report together with instructions for preparing data cards and examples of results.

Jan 1, 1972

By Kathleen J. D?Amico

THIS SUMMARY is identical to the summary given in volume III of this series of mineral production in the United States (including Alaska and Hawaii), its island possessions, the Canal Zone, and the Commonwealth of Puerto Rico and of the principal minerals imported into and exported from the United States. For further details on production see commodity and area chapters. A summary table comparing world and United States mineral production also is included. Mineral production may be measured at any of several stages of extraction and processing. The stage of measurement used in the chapter is normally what is termed "mine output." It usually refers [ ]

Jan 1, 1958

By Charles L. Kimbell

The concept of data availability must be addressed, because there are perceptible changes from year to year, and the availability of accurately reported, precisely defined statistics and nonstatistical information provides the only sound basis for analytical studies required for government policy planning or industry market analysis. As the countries of Eastern Europe and the former U.S.S.R. undergo the transition from centrally planned economies to market economies, there has been a perceptible increase in information availability for rather obvious reasons. Any industrial operation seeking economic assistance from Government and/or private sources outside the country in which the facility is sited must provide some appraisal of its operations at the time it seeks assistance, as well as some information on previous performance to serve as tools in evaluating its potential under the proposed development scheme for which it seeks financial assistance. Additionally, there was growing governmental recognition that concealment of much of the national mineral production, trade, and consumption data for purposes of national military and/or economic security probably never was very successful, never was really necessary for most commodities, and certainly proved unnecessary with the end of the so-called cold war. Indeed, the long-term unwillingness to publish uniform statistical series of reliable,

Jan 1, 1993

By Aarne Visnapuu

Experimental modifications have been made by the Bureau of Mines on standard pneumatic rock drills to reduce the noise of the air exhaust, drill steel resonance noise, and noise radiated by the drill body. A close-fitting case and muffler around the drill body, consisting of a metallic honeycomb skeleton filled with viscoelastic absorber on the inside and a durable outer shell, provide both exhaust and drill body noise muffling and absorption. Drill steel resonance noise is reduced by a constrained-layer treatment consisting of a tubular metal cover bonded to the ouside of the rod by a viscoelastic filler. Damping alloy components have been developed to reduce metallic resonance noise. Combined, these modifications have reduced the drilling noise level in granite from 115 dbA to 97 dbA. Data are presented on the individual and combined effects of these modifications on drilling noise and performance.

Jan 1, 1975

By S. J. Davenport

[The tremendous increase in mine mechanization since 1929 has increased markedly the application of electric power in and about the coal mines of the United States. Cutting, drilling, and leading machines have replaced hand-mining methods in nary mines. As a result, expansion of the gathering haulage has necessitated introduction of extensive feeder, trolley, grid other power wires. (1)3/ In spite of this vast mechanization the fatality rate from electric shock has been on the decline. However, there are still too many accidents, and efforts to eliminate electrical hazards cannot be relaxed. It is hoped that an acquaintance with the physiological aspects of electrical accidents will make workers end management aware of the lurking dangers of this very common and extremely dangerous form of energy.]

Jan 1, 1951

By Howard C. Turnage, Dana T. Updyke

An evaluation was made of one of several improved underground communication systems sponsored by the U.S. Bureau of Mines. The system evaluated was installed in a typical metal/non-metal room and pillar mine and utilized UHF repeaters connected to a unique distributed antenna and passive reflector system which provided mine-wide communications. A microprocessor controlled data collection system was assembled and installed for the evaluation. Data consisting principally of times and durations of messages and identities of the originating transceivers was collected between February and August of 1982 (6 mos.). Analysis of the data shows that the principal benefits are reduction in time required for unscheduled maintenance and repair, enhancement of safety, and better coordination of production activities. A cost benefit analysis shows a net benefit over cost, although it is also concluded that the capacity of the system is greater than can be justified by current activity in the mine.

Jan 2, 1983

By David E. Siskind

The Bureau of Mines has studied the fracturing produced in the vicinity of large-diameter blastholes in Lithonia granite. Cores were taken from the vicinity of AN-FO production blasts and examined using a total of seven laboratory and field measurement techniques to delineate zones of damage and evaluate the effectiveness of the seven diagnostic tests for fracture-state determination. Laboratory measurements of acoustic pulse velocity, porosity, permeability, compressive strength, and Young's modulus indicated the extent of fracturing with the acoustic techniques providing the best means of distinguishing between fractured and unfractured core. A severely fractured zone was found to extend approximately 25 inches (64 cm) from the center of the 6-l/2-inch blastholes, equivalent to 8 blast-hole radii. A second zone, characterized by a lesser degree of fracturing extended from 25 to 45 inches (64 to 114 cm) or 8-to l4-blasthole radii. Beyond 45 inches (114 cm) the rock was undamaged.

Jan 1, 1974

By H. Billmayer

This report covers the period from June 17, 1974 to February 20, 1975, and describes the work performed in compliance with the requirements of Contract No. H0346102 and Modification No. 1 thereto. The purpose of the contract was to design protective canopies for an Elkhorn Scoop, a Lee Norse Miner, a Wilcox Miner and a Wilcox Bolter; to construct mockups of the canopies; and to obtain machine operator evaluations of the canopy designs by assessing the mockups while installed on their machines in the mines. The overall program objective was to achieve protective canopy designs for the four machines which would be acceptable to the operators.

Jan 1, 1975

By d&apos, Kathleen J. Amico

THIS summary appears in Minerals Yearbook volumes I and III, which cover mineral production in the United States, its island possessions, the Canal Zone, and the Commonwealth of Puerto Rico, as well as the principal minerals imported into and exported from the United States. The several commodity and area chapters contain further details on production. A summary table comparing world and U.S mineral production also is included.

Jan 1, 1964

By John S. Berber

Bureau of Mines research on the production of phthalic anhydride by vapor phase oxidation of hydrocarbons began at Morgantown, W. Va., in October 1960. For these preliminary studies, a known solution containing naphthalene and 1-methylnaphthalene was used. In another series of tests, pure naphthalene was dissolved in different solvents. A series of investigations was conducted with the neutral oil fraction (210° to 270° C) of a low-temperature tar obtained from the Texas Power and Light Company's low-temperature carbonization unit. The neutral oil fraction was first dealkylated, and then the product was distilled into 210° to 250° C and 250° to 270° C fractions. These two fractions were then subjected to catalytic vapor phase oxidation. Although a number of catalysts was tested, most of the experiments were made using 9 percent vanadium pentoxide on inert alumina. The activity of this catalyst did not decrease after 162 hours at 1,030° F. Studies were conducted over a temperature range from 610° to 1,180° F. An operating temperature of 1,030° F yielded 47.50 percent of phthalic anhydride from a synthetic mixture of naphthalene and 1-methylnaphthalene. The highest yield (84.40 percent phthalic anhydride) was obtained with naphthalene dissolved in toluene and also with naphthalene dissolved in methyl ethyl ketone. With a 210° to 250° C fraction the highest yield of phthalic anhydride obtained was 12.32 percent at a temperature of 900° F, and, with a 250° to 270° C fraction, it was 15.80 percent at a temperature of 875° F.

Jan 1, 1963

By Kenneth M. Earl

In its investigation of deposits of strategic minerals, the Bureau of Mines lid some development drilling at the Milan deposit in an endeavor to find an additional source of supply of copper. The deposit, which is in Coos County, northern New Hampshire, is about 8 miles northwest of Berlin. It was discovered in the seventies and was worked steadily until 1886, yielding a monthly production of 2,600 tons of ore. Lessees opened the mine again in 1695 and mined 1,500 tons. The Milan Mining & Milling Co. acquired the property in 1907 and made regular shipments of ore and concentrates until 1910. From 1911 until 1938, the tract was held by a local resident for timber land, Ventures, Limited, a mining concern with headquarters at 25 King Street, West, Toronto, Canada, acquired the property in 1938. No production has been recorded since 1910. To cut the vein below the old mine workings and to search for extensions to the northeast and southwest, the Bureau of Mines diamond-drilled eight holes for an aggregate of 3,596.2 feet.

Jan 1, 1950

By W. P. Yant

The hazard to health from contamination of air by a noxious gas depends not only on the potential harmful response attending exposure., but also on the warning properties, which in effect may be termed the "accompanying warning response," This warning may be manifested as an odor, taste, irritation of the eyes, nose, or throat, or perhaps headache, vertigo,, or nausea. These manifestations may be painful and even slightly harmful, but to a much lesser degree than the primary injury of exposure. The warning response mitigates hazards directly in proportion to the degree of intolerability which -accompanies injurious exposure, and accordingly its absence augments hazards. This accounts for the fact that the actual health hazards from a nonodorous or non-irritating gas or vapor of comparatively low toxicity sometimes equal or exceed the hazard from a considerably more toxic substance, but one which possesses a marked odor or produces eye, nose, or throat irritation in advance of harmful exposure. When a substance lacks the properties for giving warning, it is often possible to impart them by the addition of a small amount of another substance which has an exceedingly high warning intensity. The vapors of this substance, commonly termed a "warning agent" or "tracer gas," escape and mingle with the gas or vapor which lacks warning properties and thereby apprises persons of the latter's presence. The amount of the warning agent added is that which will give adequate warning in advance of serious physiological harm from the dangerous gas or vapor.

Jan 1, 1930

By W. D. Bensema, J. W. Adams, W. W. Scott, H. Dobroski

Measurements of the absolute value of electromagnetic noise and attenuation along a hoist rope were made in an operating hard-rock mine, Lucky Friday Mine, located near Wallace, Idaho. Spectra of electromagnetic noise generated by various pieces of equipment, spectra of specific noise signals at various depths, and noise and attenuation on the 4250 foot (1295 meter) hoist, were measured. Three techniques were used to make the measurements. First, noise was measured over the en- tire electromagnetic spectrum of interest for brief time periods. Data were recorded using broadband analog magnetic tape for later transformation to spectral plots. Second, noise amplitudes were recorded at several discrete frequencies for a sufficient amount of time to provide data for amplitude probability distributions. A third technique gave attenuation data through the direct measurement of field strength at various depths. The specific measured results are given in a number of spectral plots, amplitude probability distribution plots and amplitude curves as a function of depth.

Jan 10, 1974

By G. S. Scott, G. W. Jones

"INTRODUCTION In the course of the investigation the Bureau of Mines is carrying on to determine the causes, behavior, a. control of mine fires, the detection of incipient heating underground in the mines and above ground in refuse banks has received consideration.Many of the anthracite fires have been active for years and have progressed considerable distances free their original source.Some of the fires are in inaccessible territory, and it is often impossible to determine with any degree of accuracy their exact location or even the veins of coal that are afire, especially when the fire is in the upper strata and when it is impossible to go underground because of flooded conditions or the presence of an irrespirable atmosphere.In such cases, the only means by which the trend of a fire may be ascertained (as a result of any fire-fighting methods that may have been employed) are the sampling, exanination, and interpretation of the gaseous products coming from the fire area. The most important information desired is to know whether the temperature in the heated area is increasing or decreasing and to determine whether a fire that has been sealed is cooling down to normal mine temperatures or is maintaining its heat or is increasing in intensity due to infiltration of outside air.Interpretation of the analyses of gaseous products from refuse banks on the surface also should be of value in combating such fires. Refuse bank fires, with the additional danger of starting an underground fire through ignition of the outcrop, are by no means unknown in the anthracite coal region, and the causes of such fires are not always apparent. In a few cases the causes have been strongly suggestive of spontaneous origin."

Jun 1, 1938