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To quickly and more reliably measure the alignment and deflection of mine guides used to run skips and cages into a mine shaft. The Problem Conventional mine guide alignment measuring systems require the use of a plumb bob and tape measure. This method is not only laborious, but it is time consuming as well. Approach Aware of the drawbacks of the current measuring method, the Bureau of Mines designed a self-contained instrument system that can accurately perform vertical guide alignment and deflection measurements by remote control. How It Works The Bureau-developed instrumentation system, called the Guide Alignment Measuring System (GAMS), is based on conventional mechanical electronics using inclinometers and displacement transducers. The instrumentation system is attached to an operating skip or cage where it functions as a completely self-contained measurement system, operating in conjunction with nor-mal travel of the skip or cage. An on-board tape recorder or a mini-computer with memory can be used to record all telemetry.

Jan 1, 1987

By Willard L. Hunter

The Bureau of Mines smelted samples of chromite ore and concentrate from the General Services Administration (GSA) purchasing depot at Grants Pass, Oreg., in a submerged-arc furnace to establish smelting conditions and the energy requirement to produce high-carbon ferrochromium. Raw material, in the form of ore, flux, and reductant, and electrical energy are available on the Pacific coast to smelt the chromite. The concentrate can be smelted without prior agglomeration by employing hogged wood (wood chips) as a major portion of the reductant. The energy requirement is relatively low, about 3,960 kw.-hr. per ton of alloy. The ferrochromium produced will contain about 60 percent chromium. In addition to the smelting data, a statistical summary of the grade and amount of chromite purchased during the stockpile program and estimated chromite reserves and production volume are given. It is estimated that 632,000 tons of Cr203 contained in chromite of all grades is available in the western coastal States. Of this total there appears to be sufficient metallurgical-grade and beneficiable ore to sustain a smelting operation for 25 years at a consuming rate of 25,000 tons a year, utilizing material comparable to that delivered to the Government stockpile.

Jan 1, 1961

Reduce the cost and incidence of low-back pain in underground coal mines through redesign of materials-handling tasks. Background Approximately 25 pct of all injuries in mining involve trauma to the hack. These injuries account for at least 30-40 pct of worker compensation payments made by the industry, are the leading cause of lost work days in mining, and have been estimated to cost the industry $50 million annually. It is clear that the traditional approach to reduce back injuries (i.e., training) has been largely ineffective. Thus, new approaches are necessary to control this problem. This document briefly describes methods that can be used to redesign hazardous materials-handling tasks to reduce the threat of worker injury. Approach A model for redesigning materials-handling tasks is shown in figure 1. The model outlines the sequence of steps that should be followed (and questions that should be asked) when developing new strategies for handling materials in underground coal mines. A critical examination of the current supply-handling system is the first step to developing safer materials-handling procedures. The purpose is to identify hazardous tasks that can be modified to reduce injury risk. Accident analysis (a review of past accident records) and task analy¬sis (usually a videotaped analysis of hazardous jobs or tasks) arc effective methods of distinguishing areas where job redesign is needed.

Jan 1, 1992

By B. W. Madsen

As part of a program to maintain an adequate supply of minerals and metals to meet national economic and strategic needs, the Bureau of Mines conducted research to determine the diffusion coefficients for ferric ions in synthetic copper leach solutions. Determination of ferric ion diffusion coefficients in typical dump leach solutions is necessary for predicting leaching rates of copper from large-scale leaching operations and for optimizing concentrations of ferric iron in solutions to maximize leaching efficiency. Derivative chronopotentiometry, an electroanalytical technique, was used to determine ferric ion diffusion coefficients. The diffusion coefficient decreased dramatically with increasing concentration of iron in solution. An empirical model was used to relate the ferric ion diffusion coefficient to the total amount of sulfate in solution. Measuring the diffusion coefficient dependence on temperature yielded an activation energy of 5.5 kcal/mole of ferric ion. Activity coefficients of ferric ions as a function of concentration were calculated from diffusion coefficient data.

Jan 1, 1981

By John H. Scott

At the request of the Mine Safety and Health Administration, U.S. Department of Labor, the Bureau of Mines evaluated the model BT 300 C-D blasting machine tester, manufactured and distributed by Research Energy of Ohio, Inc. (REO), to determine whether the tester performed as stated by the manufacturer and responded satisfactorily to electrical faults introduced into the blasting machine circuit. Tester readings were recorded for 13 blasting machines and for 12 circuits constructed to simulate the electrical parameters of actual machines. The tester readings were acceptable for all of the blasting machines, although the switch position assigned to one machine produced an off-scale reading. The tester responded satisfactorily to the simulated circuits and detected serious voltage or capacitance faults when they were introduced. However, it did not respond accurately to certain resistance faults. Temperature tests were also made, and the tester performed equally well at temperatures of 20°, 42°, and 81° F. This tester was judged a useful accessory for field checking blasting machines for defective batteries and capacitors, despite its limitations. It is recommended that the tester manufacturer specify the lowest acceptable reading at which a blasting machine may be used and below which the blasting machine should be returned to the laboratory or manufacturer for maintenance.

Jan 1, 1981

By Launa G. Mallett, Barbara Fotta

This report examines the effects of mining height on injury rates in U.S. underground nonlongwall bituminous coal mines, controlling for both the employment size of the mine and the mining methods. Using the mine-level employment and injury data reported to the Mine Safely and Health Administration, mines were stratified by average coal seam height (<43 in, 43-60 in, and >60 in) and by the average number of employees working at the mine (<20 employees, 20-49 employees, 50-99 employees, and >99 employees). To reduce the confounding effects of mining method on injury rates, mines using longwall mining methods were identified and excluded from analysis. The employment data show that as the mine size increases, the proportion of hours worked in low seams decreases substantially. Additionally, miners injured in small, low- scam mines arc, on average, younger and less experienced than those injured in large high-seam mines. Nonfatal disabling and fatal injury rates were computed within each category of employment size and seam height for the major types of accidents (ground falls, powered haulage equipment, machinery, handling materials, slips and falls, and hand tools). Our findings suggest that, regardless of the employment size, as mining height increases, miners are at increasingly higher risk of injury from accidents due to slips or falls and accidents involving shuttle cars and falls of ground. As mining height decreases, miners are at higher risk 01 injury from accidents involving roof bolting machines, load-haul-dump types of powered haulage equipment, personnel carriers, and powered haulage conveyors. On the other hand, regardless of the height of the coal seam, miners working in large underground mines had higher rates of injuries resulting from accidents involving handling materials and nonpowered hand tools, but lower rates of injury from accidents involving continuous mining machines and lower rates of fatal injuries from falls of supported and unsupported mine roof. Finally, miners working at small mines in low or medium seams are at higher risk of being fatally injured by a ljll of unsupported mine roof. These findings suggest the importance of&apos; considering the working height of the mine, as well as the employment size of the mining operation, when developing intervention strategies to reduce injury risk to underground coal miners. Results also identify the need to further explore how mining height contributes to the frequency and severity of injuries.

Jan 11, 1997

By G. R. Hopkins

A fifth successive record in fuel efficiency was established by the petroleum-refining industry in 1937, when the average heat requirement per barrel of crude oil run to stills was 554,000 3. t. u. compared with 597,000 3. t. u. in 1936. These amounts represent roughly the heat ob¬tainable from a tenth of a barrel of fuel oil (see fig. 1). Innumerable factors can influence heat consumption at rep aeries, but only a few are important enough to be subject to statistical measurement. Foremost of these is the ratio of runs to capacity, it being generally recognized that because the fuel demands for other than stills are comparatively inelastic, total heat requirements do not increase in direct proportion to crude runs. Thus, in 1937, crude runs of 1,183,440,000 barrels wore 11 percent higher than in 1930; the average operating ratio was 93 percent compared with 79 percent in 1936; but the total heat requirement increased only 4 percent, or from 639,149 billion 3. t. u. in 1936 to 663,966 billion 3. t. u. in 1937.

Jan 1, 1938

By K. D. Plants, J. H. Holden, L. F. Willmott

Pulverized high- volatile A bituminous coal was gasified with oxygen and superheated steam in a pressure - gasification pilot plant equipped for steampickup feeding . The pilot plant operated satisfactorily at relatively high steam- to - coal ratios , but steam- to - coal ratios could not be reduced much below 0.5 lb / lb without condensation of steam or softening of the coal . Carbon gasified , gas composition , and coal and oxygen requirements were essentially the same as for a pilot plant equipped with a fluidized coal feeder . Average results from the pilot plant equipped for steam- pickup feeding were coal requirement , 37.3 lb/M ( 1,000 ) scf of CO + H₂ produced ; oxygen requirement , 358 scf /M scf CO + H₂ produced ; and carbon gasified , 87.7 percent .

Jan 1, 1964

The faculty, graduate students, and post-doctoral researchers are an integral part of the Generic Mineral Technology Center for Respirable Dust. More than fifty (50) scientists, engineers, and medical personnel are engaged in respirable dust research at five universities, The Pennsylvania State University, West Virginia University, Massachusetts Institute of Technology, University of Minnesota, and Michigan Technological University. The expertise, effort and contribution of these individuals has proven to be invaluable in the attack on respirable disease. Nationally and internationally recognized researchers in the areas of particle characterization, interaction of dust and lungs, dilution and dispersion, rock mechanics and continuing education lend their laboratory facilities, equipment and human resources to benefit the mining industry. The expertise and resources of the National Institute for Occupational Safety and Health--Division of Respirable Disease Studies is available through their relationship with West Virginia University.

Aug 31, 1989

By N. S. Dalal, W. Irr, X. Shi, V. Vallyathan

"Inhalation of crystalline silica is associated with a biphasic biologic response of acute cell injury and chronic pulmonary fibrosis. Dust induced cell membrane injury leading to the release of lysosomal enzymes and cell death has been implicated as the initial important biologic event triggering the fibrosis. However, it ls also possible other biologic reactions could alternatively, or in addition to these enzyme related cytotoxicity reactions, alter the normal functioning of cells. It is well known that phagocytic activation results in the production of oxygen radicals which are highly cytotoxic to cells. In healthy - lung, protection against the toxic effects of the normal balanced ·biologic reactions are provided by a number of defen1e systems including antioxidants. In disease or condition of overproduction of oxygen radicals, biochemical protection may be overwhelmed with resultant cellular injury.Our recent observations have shown that reactive oxygen radicals (ROR) are generated during grinding of crystalline silica. We hypothesized that these newly generated RORs may cause cell injury, lipid peroxidation, or even damage to macromolecules such as DHA. Biochemical aberrations caused by the inhalation of crystalline silica with ROR at occupational settings might overwhelm cellular and antioxidant defense systems of the lung leading to injury and subsequent fibrosis.To test this hypothesis, we have investigated the generation and decay of ROR produced by crystalline silica using electron spin resonance (ESR) and investigated its toxicity with conventional biologic tests at various time intervals after grinding. We also studied the decay of these newly generated RORs in buffer and the effect of antioxidants and scavengers in the abolition of cellular damages."

Jan 1, 1989

The Bureau of Mines evaluated short-delay coal mine detonators manu-factured by three domestic companies for electrostatic sensitivity, strength, and no-fire current level. Electrostatic sensitivity was studied in pin-to-pin and pin-to-case modes employing lO-kV potential. Strength of detonation was measured in the Bureau&apos;s underwater test fa-cility. No-fire current was measured using a constant-current power supply unit. Test procedures and experimental data are included.

Jan 1, 1985

By Christopher C. Jobes, N. Kumar Kittusamy, Alan G. Mayton, Dean H. Ambrose

Researchers with the National Institute for Occupational Safety and Health (NIOSH) conducted a systematic study to evaluate seat designs on low- and mid-coal-seam shuttle cars. The purpose was to gather additional data to support earlier findings that NIOSH seats, with unique viscoelastic foam padding, are indeed improved designs for coal mine shuttle cars. This study included a larger sample of shuttle car operators than a prior NIOSH investigation. Eight shuttle car operators participated in evaluating seat designs on the basis of perceived levels of vehicle jarring/jolting and discomfort. Researchers then compared the operators’ perceptions with field-measured levels of vehicle jarring/jolting. Seven seat designs were evaluated on low- and mid-coal-seam shuttle cars during production operations at two underground coal mines in southern West Virginia. These seat designs comprised the one already in use on each vehicle and five NIOSH designs. Experimental data were collected using accelerometers, signal conditioning amplifiers, and filters connected to a data recorder, whereas subjective data were gathered via a visual analog scale (VAS) and a questionnaire. Field trials included shuttle cars operating under full- and no-load conditions. VAS responses indicated that NIOSH-designed seats performed better relative to comfort and isolation from vehicle jarring/jolting than the existing seats used in the shuttle cars. Both mid- and low-coal-seam shuttle car operators, during no-load and full-load conditions, rated lower levels of jarring/jolting with the NIOSH seat design. Questionnaire responses indicated that shuttle car operators rated NIOSH seat designs as more comfortable. Vehicle operators most frequently suggested the addition of armrests as a way to improve the seats on the mid-seam shuttle car. The quantitative levels of vehicle jarring/jolting for the no-load condition (more severe condition for vehicle operation) showed that NIOSH seats for the mid-coal-seam shuttle car performed better than the existing seat in terms of peak acceleration and crest factor. Similarly, for the low-coal-seam shuttle car, NIOSH seats performed better than the existing seat in terms of peak acceleration, root-mean-square (RMS) acceleration, and crest factor.

Jan 11, 2006

By BUREAU OF MINES

The Bureau of Mines, in its investigations of respiratory apparatus for use in mines and allied industries; tests equipment that is voluntarily submitted by manufacturers in accordance with published schedules of tests. These tests are designed to insure that the equipment has the minimum requirements for safety in use. Approval certificates are issued for apperatus that meets the bureau's specifications, and the manufacturer is permitted to mark his equiment with a seal showing that it has been approved as "Permissible." A complete list of per- missible self-contained oxygen breathing apparatus, gas masks, and hose masks tested prior to January 1, 1930, was published in Bureau of Mines Information Circular 62309. The present list includes all equipment tested and approved prior to July 1, 1930.

Sep 1, 1930

By Donald W. Mitchell, John Nagy, Edwin M. Murphy

Information is presented on remote sealing of a mine passageway through a borehole by five methods : PPnneeuummaattiicc injection of mineral wool and sand, ureaformaldehyde foam , balloons , urethane foam, and caving by blasting . An adaptation of the method using pneumatically conveyed mineral wool was tried in an operating mine . Further research is needed to simplify and to improve the techniques involved , as well as to explore the possibilities of other methods and combinations .

Jan 1, 1964

By John T. Aydelotte, Martin J. Gavin

" Oil shale contains little or no oil as such , but it contains an organic material from which oil may be produced by destructive distillation" . This statement , or others conveying the same meaning, appears in many popular and techni cal articles on oil shale . It is based on the belief that the ordinary solvents of petroleum have but little action on the organic substances contained in oil- yielding shales , although on distillation these same shales may yield upwards of 50 gallons of crude shale oil per ton . A 50 - gallon shale thus yields by distillation 18.73 per cent of its weight as oil ( assuming the specific gravity of the oil to be 0.900 ) , although only a relatively small part of this can be recovered by extraction with such solvents as chloroform , carbon tetrachloride , and the like . In the course of certain experiments designed to determine the solubilities of different shales after they had begun to yield oil by distillation , it was found desirable to determine the quantity dissolved from certain unheated shales by various solvents , at or near the boiling points of these solvents . The method used and results obtained are presented below. These experiments were made in connection with the oil - shale investigations being conducted by the U. S. Bureau of Mines , in cooperation with the States of Colorado and Utah .

Jan 1, 1922

By H. Foster Bain

Ten years ago there was no general , country-wide service for the systematic training of miners in matters relating to safety . A beginning only had been made at a few scattered points . Under the old conditions each man was left largely to look out for himself in meeting the hazards of his day's work, and the foreman , shift bosses , and superintendents chiefly relied upon improvision when major accidents occurred . So long as the mines were small and the workers highly intelligent and well trained in routine mining methods , and when too , the pressure for output had not yet speeded up industry to the extent it has since those days , there was something to be said for this lais- sez faire attitude . When , however , the rapid expansion of industry lead to the introduction of new and little trained labor and to units of production of greatly increased size , the natural dangers of mining were greatly intensified . An accident in a small mine affects only a few; the same accident in a large mine , unless proper precautions have been taken , may cost the lives of many . The public does not generally recognize that the greatly increased outputs of the mines , of coal mines in particular , have been in recent years , obtained from substantially the same number of miners as ten years ago but with a personnel not nearly so well trained in mining . It is inevitable under : such conditions that more care must be devoted to avoiding accidents and much more elaborate preparations made for meeting them . In the years immediately preceding the establishment of the Bureau of Mines this speeding up of industry , change in the character of mine labor , and increasing hazard had all begun to be felt . Immediately prior to the organization of the Bureau of Mines , public attention had been drawn to a series of disastrous coal-mine explosions , to the increasing frequency of these disasters , and to the terrible loss of human life . resulting therefrom. One of the first problems , therefore ; confronting the Bureau was clearly that of finding methods of reducing the number of such disasters and lessening the severity of those that continued to occur . Toward this object were immediately directed the energies not only of the Bureau of Mines but also those of State mine inspectors , mine operators and various other agencies , all of whom were urged to cooperate in this great humanitarian work. The results of this work naturally cannot be measured by figures only . Work for increasing the health , safety , comfort , and happiness of human beings may not be gaged with mathematical precision . But certain features of this work as revealed by the record from year to year are of much interest . ”

Apr 1, 1921

By W. R. Huff

Yield stress and plastic viscosity values, determined from shear rate-shear stress relationships, were found to be a linear function of coal concentration for coal-water slurries containing 40, 45, 50, and 55 weight-percent of powdered coal. In the laminar region, the flow is described by an equation derived from the fact that the square root of the shear stress varied linearily with the square root of the shear rate. In the turbulent region, the friction factor was found to be inversely proportional to the velocity to the 0.12 power.

Jan 1, 1965

By Harry E. Tufft

Data were obtained by the writer from a number of the large coul-mine operators in Illinois, on the consumption and cost of timber used in their mines and the quality of the timber now being used as compared with former years. This information supplemented by comparative date for previous years published in bulletins of the filinois Coal Mining Investigation series, and other sources, is presented below. This survey is part of a cooperative study with the . S. Forest Service, of the mine timber situation, with particular regard to the economies to be derived by better selection, preparation, and storage of timber, and especially treatment with preservatives to prolong the life. Geo. S. Rice, chief mining engineer of the J. S. Bureau of Mines, under whose general direction the work was done, gave valuable advice and criticism. R. B. Miller, State Forester, contributed helpful data which he had recent- ly obtained in an independent study of the mine-timber situation in Illinois.

Apr 1, 1923

By J. M. Stuve

The standard heats of formation (?Hf°) of holmium trichloride and terbium trichloride were measured by solution calorimetry. Heats of solution of holmium and terbium metals and their anhydrous chlorides were measured in 4.360 molal HCI at 298.15° K. From these measurements ?Hf° for HoC13 (c) was calculated as -240,290 ±1,700 cal/mo1e, and ?Hf° for TbC13 (c) was calculated as -238,330 ±1,500 cal/mole at 298.15° K.

Jan 1, 1967

By Jon C. Volkwein

The industrial sand industry has been exploring new techniques to reduce dust. One company was experimenting with adding water during bagging operations to the surface of the hag, and into the product as it flowed into the bag. The Bureau of Mines, using instantaneous dust sampling instruments, measured the effectiveness of three methods of adding water. Results indicated that various types of water sprays applied in carefully controlled amounts could reduce dust up to 50% at worker locations at the bagging machine and inside a railroad boxcar. This report also discusses constraints such as product handling, customer acceptance, cold weather problems, dust collector performance, and other areas.

Jan 1, 1981