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By Jesse A. Miller

ALTHOUGH the element titanium was discovered by William Gregor in 1790, over a hundred years passed before it was put to commercial use. The first commercial application of titanium was as an alloy additive to iron and steel, and the first ferroalloys were produced domestically in 1906. Titanium pigments were developed somewhat later and have been produced in the United States since 1918. The use of titaniferous material in welding-rod coatings first gained acceptance ill the mid-30's. The metal titanium has only had commercial importance since 1948; domestic production for that year was 10 tons. The relative importance of these major uses of titanium in various forms may he gaged by the consumption of titanium dioxide (Ti02) for these purposes in 1954. Of a total of 440,000 short tons of Ti02 consumed in 1954, 95 percent of the total was consumed for pigments; 2 percent for welding-rod coatings; 1 percent for non-titanium-base alloys and carbide; and 2 percent for miscellaneous uses. The titanium-metal industry is in its infancy, but it has more than doubled its output every year from 1948 to 1954, reaching 5,370 short tons in 1954.

Jan 1, 1957

By William A. Stickney

The zirconium-hafnium separation plant at Albany, Oreg., was the result of a chain of events that started with studies by A. R. Kaufmann at the Massachusetts Institute of Technology. Variations in the listed neutron-absorption cross-section of zirconium caused him to suspect a misprint. As a result of these discrepancies and following his suggestions, Oak Ridge scientists made studies establishing a value of 0.4 barn or lower. This meant that the potential of zirconium for reactor application was greatly enhanced. Since hafnium is invariably associated with zirconium and has a high neutron cross-section, it was necessary that an efficient hafnium-separation method be developed before the superiority of zirconium as a structural material in nuclear reactors could be realized. The Albany plant was built and operated for the Atomic Energy Commission (AEC) under Letter Agreement AT-(11-1) -140, patterned after a plant operated by the Carbide and Carbon Chemicals Corp. at Oak Ridge, Tenn. Construction was begun in April 1951. Hafnium was to be extracted preferentially as hafnium thiocyanate from an aqueous mixture of zirconyl and hafnyl chlorides in hexone (methyl isobutyl ketone) by a liquid-liquid countercurrent system.

Jan 1, 1959

By Gloyd M. Wiles

The property of the Park City Consolidated Mines Co. is situated in the northeast part of the Park City dining district 1 mile east of the town of Park City. The elevation at the collar of No. 1 shaft is 7,250 feet. Park City is a town of approximately 4,500 population lying about 30 miles east of Salt Lake City. The two are connected by an oiled State Highway, which is cleared of snow in winter and maintained in first-class con¬dition by the State throughout the year. The district is served by branches of the Denver & Rio Grande Western and Union Pacific Railroads, each operating on a daily' schedule, except Sunday. These two railroads have constructed 1 ½ miles of joint track from the town to the Park City Consolidated Mines Co. loading tipple, located 200 feet from the portal of the adit that leads to No. 1 shaft.

Jan 1, 1936

By Larry A. Haas

Carbonyl sulfide (COS) was decomposed to sulfur and CO in a silent electrical discharge. A threshold of about 4 kv at 60 Hz was required to dissociate the gas in a laboratory ozonizer at 790 torr with electrode gaps between 1 and 5.5 mm. Above the threshold value, the reaction rate increased with increasing voltage with helium or nitrogen diluent. With the latter diluent, higher voltages had to be applied to obtain the same yield in the 4-to 12-kv range. The COS decomposition rate increased with COS concentration, but a saturation value was reached at about 10 pct COS. The reaction rate decreased at low linear gas velocities as obtained at lower gas flows, larger electrode gaps, or larger reactor volumes. Increasing gas temperature also decreased the decomposition rate. The presence of solid adsorbents such as quartz wool, bauxite, or charcoal had no significant effect on the reaction rate. The addition of S02 did not affect the COS decomposition rate, but small amounts of water decreased the reaction rate. Over 50 pct of the COS was decomposed at room temperature and atmospheric pressure in a l7-kv ozonizer using a gas containing 0.9 pct COS in helium flowing at a rate of 0.3 liter/min. The average current was less than 5 ma. This method has possible application in eliminating the toxic air pollutant, COS, which is generated in petroleum refineries and in processes involving reactions between sulfurous and carbonaceous materials. Carbon monoxide that is formed can be further oxidized to CO2 after the collection of elemental sulfur.

Jan 1, 1972

By Donald James Butler

Problems resulting from underground mines in three inactive mining districts in Colorado were investigated. The purpose was to determine how these problems could be reduced or eliminated in new closings -- essentially by benefitting from lessons of the past. Mines in Leadville, Westcliffe and the Cripple Creek-Victor districts were evaluated. Two basic types of problems were found to exist in the districts: environmental degradation and hazardous conditions. Environmental problems result largely from acid and toxic drainage from the runes and from leaching of surface waste rock piles and mill tailings impoundment. The acid drainage contributes high levels of metals to streams and deposits sediment in the stream bottoms. Erosion of waste piles is a lesser problem. Hazardous conditions from open or improperly sealed mine shafts and adits, mine subsidence pits, and from deteriorating and unsafe surface structures are common to the three districts. These problems become worse with the ravages of time and vandalism. Engineering solutions which would correct or reduce many of these problems are presented. These recommendations should also be applied to new mine closures, however, more basic changes are needed to effectively implement improved mine closures. The changes must take place in the areas of legislation, mining practices and education. Legislated regulations should realistically reflect the needs of both the mine operators, protection of the environment and the best interest of the general public. Benefits should be provided for compliance with regulations instead of penalties being assessed for noncompliance. Hazardous conditions and environmental problems associated with mines can be alleviated through improved mine design and effective cloning procedures. Education should provide an appreciation by the general public of past and present problems facing mine operators. This will result in an improved mining climate which, in turn, will insure a continuing supply of minerals to meet increasing needs.

Jan 1, 1983

By Magnus Persson

ISO8662-4, “Hand-held portable power tools - Measurement of vibrations at the handle - Part 4: Grinders” is under revision. The new revision shall harmonize ISO 20643 “Mechanical vibration - Hand-held and hand-guided machinery - Principles for evaluation of vibration emission” which, among others, requires measurements in three directions and declared values related to the upper quartile of real-use vibration. To get the most suitable test method, a round robin test was made for evaluation of the two test methods proposed by the ad-hoc group working with this standard revision. Methods Seven laboratories measured the vibration from four grinders of different sizes, with and without autobalancing units. The laboratories come from universities, health & safety laboratories and grinder manufacturers. Two measurement methods are evaluated with respect to repeatability and reproducibility: 1. Grinding on a well-defined mild steel bar with depressed center wheels according to detailed test instructions. The test sequence starts and ends with 10 seconds of running the grinder in the air, when measuring the unbalance contribution to the vibration coming from the unbalance of the grinding wheel. Between these runs the average vibration during 60 seconds of grinding is measured. Three operators do five grinding tests per grinder. 2. Measurements using an aluminum unbalance disc similar to the one defined in ISO8662-4. Each operator runs the grinder four times, between each run the unbalance is moved 180 degrees to avoid variations caused by the play between the test wheel and the spindle. The averaging time is 10 seconds. Each grinder is tested by three operators. Repeatability is the spread within a lab between operators and over short time period for one machine and reproducibility is the spread between laboratories and over longer time periods for one machine. Instrumentation and transducer location are chosen according to ISO8662-4 and circulated test instructions. Results Both the repeatability and reproducibility is poor for the real grinding test, see figure 1. The coefficient of variation for repeatability is approximately 40% higher for the grinding test and the coefficient of reproducibility is 60% higher for the grinding test than for the unbalance disc test.

Jan 6, 2006

By R. W. Fatzinger

The accident-frequency rate for placer mining in 1942 is reported as 36.923 accidents per million man-hours worked. This figure places placer-mining accident frequency slightly higher than that given for quarrying-35.7-but considerably under the 78.0 for coal mining and 56.5 for metal mining.4 Placer mining is subdivided into four types of activity: Underground, surface, dredging, and hydraulicking. It is the purpose of this paper to present and discuss safety practices in dredging and hydraulic mining; therefore, the following considerations will be limited to these two types of placer mining.

Jan 1, 1948

By P. B. Grote

The report provides a general description of DOM technology, sources for DOM technology, and identifies approaches and requirements for acquisition by the Enterprise of DOM technology by conventional means. The approaches identified assume the Enterprise enters into a contractual/ joint venture arrangement with an uncommitted and competent systems management firm at various stages of the DOM system acquisition process. The approaches provide for training through work/study as well as through direct participation in acquisition programs. The potential success of the alternatives are evaluated in terms of the likelihood of the acquisition of an ongoing Enterprise economic DOM operational capability. The study concludes that sources exist and that the Enterprise should under-take the development of its own technical capability through conceptual design prior to selecting its source for systems management expertise.

Jan 1, 1980

By Bruce Pinkston

This report presents a description of the Prototype Demonstration Vehicle developed under U.S. Bureau of Mines Contract No. JO 366003, "Improving Man Transit Safety". This vehicle was constructed to assess the feasibility of a set of equipment related guidelines which were drafted in Phase I of the same contract. State-of-the-Art improvements were embodied in such areas as collision survivability, occupant comfort, and multiple mode (on and off rail) operation. The electric battery-powered vehicle carries a twelve man section crew at speeds up to 12 mph. The description of the demonstration vehicle is presented in Volume I. Safety Guidelines are presented in Volume II.

Jan 1, 1981

By N. Grosland, G. Kopp, T. Hunstad, D. Wilder, M. Contratto, S. Rahmatalla, T. Xia

Chronic whole-body vibration exposure, as expected in large construction and mining vehicles, has been associated with neck and back pain and injury.1 While work has been done towards gaining a better understanding of the relationship between vibration and shock and muscle activity of the back musculature2, relatively little information regarding the activity of neck, shoulder and upper arm muscles is known. Today’s equipment designs must conform to domestic and international standards, however these standards do not specifically address the vibration exposure in the head and upper quarter. Further it is not well known how the control configuration within a vehicle (e.g. steering wheel versus arm controls) influences muscle voluntary and reflex activity levels. Greater muscle activity may lead to greater muscle fatigue – which in turn may be associated with greater risk of injury.2 Thus, muscle contractions needed to maintain static postures as well as those resulting reflexively should be considered during an analysis of seating position. Unfortunately, little is known regarding the influence of arm position on head and neck muscle function. The purpose of this study was to investigate the relative muscle activities of 5 neck, shoulder, and upper arm muscles during riding simulations of large construction equipment, using three different arm control options. Methods Five typical heavy equipment ride files were “played back” through a man-rated Servo Test 6-degree of freedom (dof) vibration system. Each ride was repeated using 3 seat and control configurations (steering wheel (SW), floor mounted arm-rest controls (FM), seat mounted arm-rest controls (SM)). Two trials were performed for each ride and seat control combination (each trial: 60 sec of 6-dof and 60 sec of vertical vibration). Five channels of surface electromyography (EMG) of the right-side cervical erector spinae muscles (neck extensors), sternocleidomastoid (neck flexor), upper trapezius (shoulder elevator), biceps brachii (elbow flexor) and triceps brachii (elbow extensor) muscles were collected throughout each ride (~ 2min) using pre-amplified (10x), 1 cm silver bar electrodes, with 1 cm fixed inter-electrode distances (Delsys, Inc). Further analog amplification was set at 10k (1k for one subject), and sampled at 1000Hz using a 12-bit DAQ card and Labview 7.1 software (National Instruments). A total of 7 right-handed male subjects were tested, but only 5 had complete EMG data sets to analyze for this sub-study. EMG was analyzed using root mean square (RMS, in mV) of 20 ms moving windows, and then averaged across the entire trial for a measure of mean total muscle activity (voluntary and reflexive). The muscle activity to maintain the static posture was estimated as the mean RMS EMG over a 1 sec interval just prior to and/or after completion of the ride. Repeated Measures ANOVAs were used to test for with-in subject differences using a = 0.05.

Jan 6, 2006

By J. L. Thompson

The U.S. Bureau of Mines conducted a water-jet-studies program using a single-bit, in-seam test unit to determine effects of a moderately high-pressure (up to 10,000 psi) water-jet-assisted cutting system on rock weakening. The in-seam test unit was used to obtain cutting force data in tangential, normal, and side force directions. Conical continuous miner and radial longwall miner bits were used to penetrate test samples of coalcrete, Berea sandstone, and Indiana limestone with unconfined compressive strengths of 4,600, 8,000 and 10,000 psi, respectively. Depth of cut in the coalcrete tests was 1 in, with 2-in cut spacing (2:1 ratio). Because of cutting equipment and instrumentation limitations, the Berea sandstone and Indiana lime-stone were cut using a 0.5-in depth of cut and 2-in spacing (4;1 ratio). Bit velocity was maintained at 25 ft/min for both bits. Each specimen and bit type was tested using 0.3-, 0.6-, 0.8-, and 1.0-mm-diam nozzles and water-jet pressures of 2,500, 5,000, 7,500, and 10,000 psig. Water-jet-assisted cutting decreased average resultant conical and radiallongwall bit cutting forces 6.4 and 8.4 pct in coalcrete, 5.5 and 1.4 pct in Berea sandstone, and 2.0 and 5.5 pct in Indiana limestone. Slight reductions of power requirements resulting from water-jet assist were ascertained during these experiments.

Jan 1, 1989

By Adrian Brown

Pilot Hole ?X? was drilled to test the formations through which the ventilation shaft for the proposed U.S.B.M. demonstration oil shale mine will be drilled. Five permeability tests were performed at various stratigraphic levels within this hole. The test method used was that of pumping fluids out of the hole for three hours, using the air lift method, followed by a three-hour period where the recharge was observed. Transmissivity and permeability results were determined from these test data. The test procedure used is described and supporting data for the hydrologic tests are provided.

Jan 1, 1977

By K. K. Kelley

The first bulletin (269) 3 in this series, which appeared in 1932, compiled the entropy values then available for the elements and in-organic compounds, results being listed for some 150 substances. Elaborations and revisions followed in 1936 (272) and 1941 (280), when over 500 usable entropy values were tabulated. The present bulletin constitutes a further elaboration and revision. The accumulation of data since 1940 has been marked, and 800 entropy values now are available. The present bulletin also contains all the pertinent explanatory matter that appeared in its predecessors. Thus, it retains the same dual purpose of assembling the available values of the entropies at 298.16° K. of the elements and inorganic compounds and giving enough explanation of methods of calculating entropies to make the results comprehensible.

Jan 1, 1950

By Annie G. Smelley

As part of its program to develop technology that will encourage maximum utilization of the Nation's mineral resources, the Bureau of Mines conducted research on debrining potash-clay waste slurries by means of flocculation with a high-molecular-weight polymer and subsequent solid-liquid separation on a rotating trommel screen. In laboratory batch tests, potash-clay waste slurries were consolidated from initial clay contents of 8 pct to final contents of 30 pct with a polymer dosage of 1.2 Ib/ton of dry clay waste. Small-scale continuous tests yielded debrined products containing 20 pct solids using a polymer dosage of 1 Ib/ton of dry clay solids.

Jan 1, 1983

By Calvin K. Lee

This Bureau of Mines report describes a simple fire-retardant treatment for wood. The treatment involves preheating the wood surface at high heat flux (~0.6 cal/cm2 sec) to form an in situ surface char layer (~3 mm thick) on the wood. Laboratory-scale fire tests show that the precharring technique improves the fire-resistance of virgin wood by decreasing and delaying generation of volatile gases through thermal insulation effect of the surface prechar layer.

Jan 1, 1978

By Kim B. Shedd

An initial evaluation of the flow of cobalt-containing materials in the United States was prepared. The following aspects of materials flow were included: cobalt released as a result of mining and processing other metals and minerals; scrap generation and subsequent recycling or cobalt recovery; and cobalt losses resulting from the generation of wastes, dissipative uses, and disposal of used products. Where possible, estimates were made to quantify the amount of cobalt lost from the materials flow. More than 2,000 metric tons (mt) of cobalt are released annually from mining and mineral processing in the United States, including 480 mt of cobalt in coal produced in the United States. Metallurgical industries examined in this study have well-established recycling or cobalt recovery practices. The petroleum industry recycles spent catalysts, and some chemical catalysts are also recycled. Losses generated during cobalt chemical and powder processing were estimated at 50 to 80 mt of cobalt annually. Losses from alloy processing and the manufacture of parts and products were estimated to be 360 mt. These industrial losses are greatly outweighed by an estimated 2,780 mt of cobalt' consumed in the United States each year to make products that will ultimately be disposed of.

Jan 1, 1992

By C. Froger

Since its creation in 1950, the Centre d'Etudes et Recherches des Charbonnages de France at Verneuil-en-Halatte (Oise) has been conducting many investigations concerned with airborne dust measurements, particularly in underground mines. The work has resulted in the development, a few years ago, of a new process of dust sampling, whereby the airborne dust particles are collected by a rotary filter of polyurethane foam rotating at high speed within 8 housing.

Jan 1, 1973

By W. W. Adams

Rock dust, as a preventive or limiting factor in explosions of gas and coal dust in bituminous-coal mines, was used in larger quantities in 1939 than in any other year except 1937 since annual figures first became available in 1930, Reports from mining companies to the Bureau of Mines revealed that 144,430,000 pounds of rock dust was applied to underground mine workings in mines that produced 126,635,677 short tons of coal during the year. This quantity of rock dust applied averaged 1.14 pounds for each ton of coal produced. Rock dusted mines were the source of 39.7 percent of the total production of bituminous coal from underground mines; 33.2 percent of the total number of underground workers were employed at rock-dusted mines, and 35.9 percent of the total number of man-hours worked underground at all bituminous-coal mines in the United States during 19719 can be accredited to mines so treated.

Jan 1, 1940

Electrical trailing cable used to power coal mining machinery is frequently damaged by tensile strain or crushing by mining machines running over the cable. A major problem is finding the exact location of a short or open in this cable so it may be repaired. A major problem is finding the exact location of a short or open in this cable so it may be repaired. FMC Corporation was awarded modification III to USBM Contract H0122011 to continue development and testing of cable fault locators, resulting in delivery of: 1. A prototype electrostatic/electromagnetic/ TDR transmitter and an electrostatic/electro-magnetic receiver sot that: o Locates cable faults by time domain reflectometry o Locates opens by detecting electrostatic signals o Locates shorts by electromagnetic coupling. 2. A prototype infrared detector and an infrared detector power supply that heats a shorted area by applying high current (at low voltage) and locating a short by infrared output. 3. Twelve production infrared detectors. 4. Detail drawings for all of the developed instruments.

Jan 1, 1973

By W. W. Adams

Rock dust, as a preventive or limiting factor in explosions of gas and coal dust in bituminous-coal mines, was used in larger quantities in 1939 than in any other year except 1937 since annual figures first became available in 1930, Reports from mining companies to the Bureau of Mines revealed that 144,430,000 pounds of rock dust was applied to underground nine workings in mines that produced 126,635,677 short tons of coal during the year. This quantity of rock dust applied averaged 1.14 pounds for each ton of coal produced. Rock dusted mines were the source of 39.7 percent of the total production of bituminous coal from underground mines; 33.2 percent of the total number of underground workers were employed at rock-dusted mines, and 35.8 percent of the total number of man-hours worked underground at all bituminous-coal mines in the United States during 19719 can be accredited to mines so treated. Rock dust was employed chiefly in the larger mines, which numbered only 431 out of 6,016 underground mines in operation in 1935, according to reports from mining companies. The mines in which rock dust was used had an average of 288 underground employees per mine, whereas mines in which rock dust was not used averaged only 62 underground employees per mine.

Jan 1, 1940