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By W. Hermanson

This report presents the results of a task to complete a final design of a remote controlled hi-roof bolting machine for high roof areas in coal mines. The project was begun by visiting several coal mines to become familiar with roof fall areas. Several machine concepts were generated and presented to the design committee for criticism. A preliminary design was completed, as covered by this report. A Final Design and Final Report will be issued incorporating the committee comments at the Preliminary Design review and comments received concerning this Preliminary Design Report.

Jan 1, 1979

By Laurance L. Oden

The Bureau of Mines is developing melting data for binary combinations of the alkaline earth fluorides and yttria to facilitate the formulation of slag compositions. The present report deals with the SrF2-Y2O3 system for which liquidus and solidus temperatures and solid solubilities were determined. The information is presented as the phase diagram. The phase diagram was constructed from information obtained by ceramogra¬phy, X-ray diffraction, thermal analysis, and electron probe microanalysis of small specimens encapsulated in platinum-20 percent rhodium or molybdenum ampoules. The data indicate a simple eutectic system with limited terminal solid solubilities. The eutectic temperature is 1,457°±5° C, and the eutectic composition is 4±1 mole-pct Y203. Strontium fluoride containing up to 2 wt-pct 0 2 was studied to determine the effects of oxygen contamination. Oxygen levels in excess of 0.2 wt-pct resulted in eutectic formation between SrF2 and SrO. The eutectic composition is between 0.2 and 0.7 wt-pct 02, and the eutectic temperature is 1,447°±5° C. No intermediate oxyfluoride phases were detected.

Jan 1, 1974

By Edward Thomas

In 1947 the Bureau of Mines, as an accident-prevention measure, decided to advocate the adoption of roof bolting (suspension roof supports) in coal mines where it appeared to be applicable. Subsequent experience has disclosed that the applicability of this support is more general than was first suspected; moreover, comparison of the accident records of mines before and after adoption of the roof-bolting method shows results that more than justify the effort and funds expended. The industry has responded enthusiastically, because roof bolting proved to be not only an accident-prevention measure but also one to increase productive efficiency. In some instances this increase in the productivity of men and machines has been almost incredible and has led many mining men to conclude that through some hocus-pocus they can now cast aside many or all of the time-proven rule of good mining practice. If this tendency is not counteracted, it could easily result in an increase of roof-fall accidents, which may outweigh the benefits of roof bolting and discredit an innovation in roof control that shows great promise of materially reducing our mining accidents. From an economic standpoint it may represent the margin between profit and loss in many mining operations. The purpose of this manuscript is not to propose an inflexible code or set of rules but to summarize the experience to date as a guide for those who have the responsibility for the installation and inspection of roof bolts. This experience consists of approximately 250 investigations of roof failure in which roof bolting was involved either directly or indirectly. It should be pointed out that many of these failures were controlled, occurring during experimental periods, and comparatively few of the accidental failures actually resulted in personal injury, yet a significant number represented potential hazards.

Jan 1, 1951

By BUREAU OF MINES

PLATINUM

Feb 1, 1922

By J. L. Eakin

A method was developed by the Bureau of Mines in the laboratory and in the field to relieve capillary waterblocks in gas wells. Impaired gas permeability was improved by this inexpensive chemical treatment which lowers the surface tension of the water held in the capillaries of the formation. Effectiveness of the alcohol-surfactant treatment was tested with a variety of chemicals and with sandstone cores cut from rocks having relatively low permeability. Field tests on 20 gas-producing and storage wells demonstrated the effectiveness and limitations of the method. The productive capacity of some wells was doubled by the treatment. The final test was evaluated by the neutron logging technique for measuring changes in apparent liquid saturation. Maximum apparent liquid saturation was reduced by 52 percent; gas production rate increased from 2.3 to 3.5 MMcfd (million cubic feet per day).

Jan 1, 1965

By Fred C. Turin, Jasinder S. Jaspal, Alan G. Mayton, William J. Wiehagen

This report describes serious injuries occurring to bulldozer operators working at U.S. coal, metal, and nonmetal mines. The period covered is 1988-97. The data were collected by the Mine Safety and Health Administration (MSHA). A total of 873 injury records are examined. These injuries resulted in 18 fatalities and 31,866 lost workdays. All of these injuries occurred to dozer operators while they were doing common production tasks. An injury classification system was developed to code the narrative information that describes the circumstances surrounding the injuries. Injury records are categorized by activity (task being done), incident result (what apparently happened to the dozer), and operator impact (how the operator was injured). Where information is available, contributing factors are identified. This classification system supplemented the standard injury/illness data classification system compiled by MSHA. The results of the study indicate that, from 1993 to 1997, the number of serious injuries to dozer operators declined by 30%. The reduction in serious injuries was accompanied by a decrease in days lost due to injury. Although the number of reported injuries has decreased, dozer operators being jolted and jarred accounts for the largest percentage (70% of the incidents) and severity (75% of the workdays lost) of serious injuries while operating the equipment. Vertical jars (while backing up the dozer) resulting in injury to the operator accounted for a sizable percentage of jolting and jarring injuries. Working near an edge carries significant risk for fatal injuries. Of 116 incidents where the dozer fell over an edge, rolled over, or fell into a hidden void, 14 (12%) resulted in fatal injuries. In cases where the dozer operator either jumped or was thrown out of the cab in a fall over or rollover, 7 out of 26 were killed. Overall, 80% of the fatalities occurred while working near an edge or hidden void or on a steep slope. Further reductions in injury risk will require more widespread use of seatbelts, field and laboratory research interventions to better assess the effect of alternative engineering (e.g., seat and seat suspension) designs to dampen or isolate the effects of shock and vibration, and continued focus on hazard awareness, recognition, and response.

Jan 4, 2001

By Ronald D. Hill, Elmore C. Grim

Coal-haul and mine access roads are defined as any road constructed, improved or used by the operator (except public roads) that ends at the pit or bench. These roads constitute approximately 10% of the total area directly disturbed by the surface mining operation(l). In some cases, the land disturbed by haul roads exceeds the area included in the mining operation. Studies (2 and 3) of the U. S. Forest Service in eastern Kentucky show that typical contour mining roads exhibit poor alignment, excessive grades, insufficient strength and durability, and poor drainage. Mine roads in other Appalachian- States, particularly where contour mining is practiced, appear much the same as those in Kentucky. Access roads(4) were also found to be a large source of sediment. It is possible that of the sediment that finds its way into the streams as much (or even more) originates from the haul roads as from the mining operation. Most roads are built as cheaply as possible, and good road-building design and practice are ignored. Maintenance schedules are generally inadequate, and upon completion of mining, haul roads are usually abandoned, with little or no attempt made to bed them down(5 ) . Such roads deteriorate very rapidly (Figure 68). Area mining, which is practiced in flat to gently rolling terrain, presents fewer haul road related environmental problems. These roads through necessity are generally well engineered because of the heavy equipment using them, such as 240 ton (217 metric ton) haul trucks. They must have wide beds, good alignment, and adequate drainage to permit coal haulers to run at top speed during all seasons of the year. Excessive dust can be a public nuisance and a driving hazard, and it is hard on equipment. Calcium chloride and sodium chloride have proven to be effective materials for controlling dust. Two applications during the summer when the ground surface is moist at the rate of 1/2 pound per square yard (.26 kilograms per square meter) (3 1 have been suggested. Th4 most common procedure is to keep the roads wet by using water trucks. Sediment that reaches the streams can be traced to one or more of the following five basic phases of haul-road life:

Jan 1, 1974

By Keith D. Rosbury

The basic objective of this project was to determine the cost-effectiveness of dust control used on unpaved mine haul roads. Field testing was conducted at three surface coal mines (two in Wyoming, one in southern Illinois) for a total of 20 weeks. The highest control efficiency measured for a chemical dust suppressant, 82 percent, was for calcium chloride two weeks after application. Generally, however, the control efficiencies hovered in the 40 to 60 per-cent range over the first two weeks since application, and then decreased with time. After the fifth week, the limited number of data points suggest a control efficiency of less than 20 percent. Composite watering data were fairly uniform. Watering once per hour resulted in a TSP control efficiency of approximately 40 percent. Doubling that application rate increased the control effectiveness by about 15 percent to 55 percent. Chemical dust suppressants (primarily salts and lignons) can be shown to be more cost-effective than watering under some conditions. Delta summaries and the analysis of data are contained in Volume I. Volume II contains basic data.

Jan 1, 1983

By W. M. Nabors

As part of a program to promote conservation and efficient utilization of petroleum resources, Bureau of Mines engineers at the Morgantown (W. Va.) Petroleum Research Laboratory are studying secondary oil-recovery projects in the Appalachian region. The increasing demand for petroleum and its products and the increasing cost of exploratory drilling tend to emphasize the importance of improving the recovery of oil from known petroleum reserves. Published reports setting forth the pertinent facts of these operations may help others to profit by the experience. This report presents the results of a study of secondary-recovery methods used in West Virginia by the Piedmont Oil and Gas Co., the Ryan Oil Co., and Water floods , Inc., on their Roane County leases in the Walton and Clover Rush Run pools. The principal oil-producing horizon underlying the area studied is the Big Injun sand, at approximately 2,000 feet. The sand is often referred to as blanket sand because it underlies much of the State and is oil-productive in many localities. Most of the pools in the area were discovered during 1907 to 1910 and were similarly developed and operated.

Jan 1, 1960

By T. J. Ballard, Austin B. Clayton

"INTRODUCTION The Conrad Hill mine was first opened as a gold mine about 1832 and has been operated at various times since then.The Bureau of Mines, as part of the strategic minerals program, mapped and sampled the accessible mine workings.The: work failed to reveal appreciable copper values or evidence of additional ore deposits.ACKNOWLEDGMENTSIn its program of investigation of mineral deposits, the Bureau of Mines has as its primary objective the more effective utilization of our mineral resources to the and that they make the greatest possible contribution to national security and economy. The Mining Division, Lowell B. Moon, chief, conducts preliminary examinations, does the actual investigative work, and prepares the final report. The Metallurgical Division, Oliver C. Ralston, chief, analyzes samples and makes beneficiation tests.The field work embodied in this report was under the direction of Austin B. Clayton. The final report was prepared by T. J. Ballard uncle,- the general supervision of Mitchell H. Kline, chief, Raleigh, N. C., Branch, Mining Division. Analyses of samples and beneficiation tests were made by the Metallurgical Division. ACCESS AND OWNERSHIPThe property is 6 miles southeast of Lexington, N. C., and can be reached by U. S. Highway 64, turning off at Hedrick Grove Church, and is 1 mile north from the highway on the county road. The mine is in Davidson County at approximately 35° 47' latitude and 80° 10' longitude (fig. 1).The property comprises 471 acres and is owned (1943) by the McKeeMining Co., 512 Fifth Avenue, New York City. The property was optioned to Woodrow McKay of Lexington, N. C., in 1943, who in turn subleased the property to the Robert G. Lassiter interests of Raleigh, N. C."

May 1, 1948

By F. F. Hintze

In the group of minerals used in making this study, the cyanite is associated with quartz, mica, and feldspar in the schist. The amount of quartz is variable, but it is always an abundant mineral. Both large and small crystals of quartz occur in irregular masses, rarely ever showing crystal outline. Mica is of the clear and dark varieties, the larger crystals being dark as a rule, and the finer crystals of light color. The present mineralogical composition of the mina is rather variable, as most of the original biotite and muscovite have suffered alteration, and much secondary mioa is present as a result of alteration of the original mica and other minerals present, especially the larger cyanite crystals. A large part of the mica now found in the ore is chlorite, with varying amounts of Jefferisite and others, especially sericite. These are in the form of aggregates, or felt-like intergrowths filling the spaces between the quartz, cyanite, and feldspar.

Jan 1, 1931

By J. B. Littlefield

This study is one of a number conducted to determine the concentration of dust in the air during the complete cycle of operation in wet drilling information as to various factors connected with drilling in mining operations is considered to be of definite value in the control and prevention of air dustiness, and it is particularly desirable to ascertain What features of present-day wet-drilling operations in mine work contribute to dust disease and to remedy deficiencies when they are found. ACKNOWLEDGMENTS A testing alit through rock strata is being developed by the Mining Division of the United States bureau of Mines at Mount Weather, Va., and the tests discussed in this report were conducted there. This experimental alit in rock, constitutes a typo of laboratory where mine conditions can be closely simulated and where many of the variables likely to occur in an actual mine can be eliminated or at least controlled with reasonable effort, thus affording maximum opportunities to secure fundamental data uncomplicated by extraneous conditions. The authors wish to acknowledge the valuable assistance and cooperation of several members of the Mining Division, particularly C. F. Jackson, chief engineer, McHenry Mosier, associate mining engineer, and G. E. McElroy, supervising engineer, mine ventilation.

Jan 1, 1938

By F. R. Cattoir

Analytical methods are presented in this paper for determining soluble titanium, total titanium, indicated titanium, and average effective valence in titanium chloride - sodium chloride mixtures. In addition, data are given showing the effects of coarse and fine grinding on the degree of oxidation and average effective valence of such samples. INTRODUCTION The Electrometallurgical Experiment Station at Boulder City, Nev., as part of the Bureau of Mines program to obtain more efficient utilization of our natural resources, has been developing and improving titanium extractive metallurgical methods and techniques since 1945. Numerous reports have been published describing development of the Kroll process,4/ the electrorefining technique,5/ and methods of analyzing titanium sponge.6/

Jan 1, 1957

By J. B. Littlefield

This study is one of at number conducted to determine the concentration of dust in the air during the complete cycle of operation in wet drilling; information as to various factors connected with, drilling in mining operations is considered to be of definite value in the control and prevention of air dustiness, and it in particularly desirable to ascertain whet features of present-day wet-drilling operations in mine work contribute to dust disease and to remedy deficiencies when they are found.

Jan 1, 1938

By William P. Diamond

This report presents results of a cooperative research project between the U.S. Bureau of Mines and BethEnergy Mines, Inc. Four coreholes (two before mining and two after mining) were drilled at a longwall mine operating in the Lower Kittanning Coalbed to obtain coal and rock samples from over-lying strata to determine their gas content at various times in the mining cycle. The results of those tests indicate that 91 pct of the gas removed from the overlying strata came from coalbeds. Material balance calculations were made to compare the volume of gas produced both from gob gas vent holes drilled on the panel and gas removed by the mine's ventilation system with the volume of gas removed from strata directly overlying the panel to a height of 275 ft. This analysis indicates that only 40 pct of the total gas produced from the panel actually came from the strata directly overlying the panel. The remaining volume of gas production probably migrated to the longwall gob from overlying, and perhaps underlying, strata immediately adjacent to the panel and perhaps from greater distances downdip because of the establishment of a long-term pressure gradient in the study area.

Jan 1, 2010

By A. U. Miller

For many years Illinois has been one of the leading coal producers in the United States and as such its safety record has compared very well with the other large coal producing States , both in tons produced and millions of man -hours of exposure per fatal accident . ( See Table 25 in Bureau of Mines Bulletin 293. ) During the 10-year period from 1917 to 1926 , inclusive , the average production in the United States per fatal accident was 278 , 109 tons . The aver age for the State of Illinois for the same period was 409,249 tons . Illinois produced 450,464 tons per fatal accident, and in 1928 produced 390,630, tons , or an average of 419,721 tons for the 12- year period from 1917 to 1928 , inclusive . In 1927 During the year 1929 , the shipping mines of the State made a decided improvement in their record over any previous year . Table 1 shows the monthly production and the tons produced per fatal accident . During 1928 and 1929 safety work was actively carried on in Illinois . Safety meetings were held with mine officials , representatives of the State. De partment of Mines , and the United States Bureau of Mines . At these meetings mine hazards and accidents were discussed and remedies suggested for : their elimination in the future . It is believed that first - aid training was to a considerable extent instrumental in reducing accidents and in making the good safety records in Illinois during 1928 and 1929. During these years ( as well as in 1926 and 1927 to a somewhat less extont ) en intensive rirst-aid training campaign was con ducted in Illinois by the officials and members of the United Mine Workers of America , coal companies, State Department of Mines and Minerals , and the U. S. Bureau of Mines , Every first -aid class was made a safety meeting ; where accidents and general safety were discussed freely while teaching first aid. During this time , anproximately 25,000 persons were trained in first aid, and 17 coal companies were issued certificates for having 100 per cent of their employees. trained in first aid. Since January 1 , 1926 , more than 40,000 have received first -aid training in and around Illinois mines , and including those who received training previous to this date , it is believed that at least 90 per cent of the miners in Illinois have received first -aid training . This state ment is based on the fact that the labor turnover in Illinois is not large .

Apr 1, 1931

By F. F. Hintze

In the group of minerals used in making this study, the cyanite is associated with quartz, mica, and feldspar in the schist. The amount of quartz is variable, but it is always an abundant mineral. Both large and small crystals of quartz occur in irregular masses, rarely ever showing crystal outline. Mica Is of the clear and dark varieties, the larger crystals being dark as a rule, and the finer crystals of light color. The present mineralogical composition of the mina is rather variable, as most of the original biotite and muscovite have suffered alteration, and much secondary mica is present as a result of alteration of the original mica and other minerals present, especially the larger cyanite crystals. A large part of the mica now found in the ore is chlorite, with varying amounts of Jefferisite and others, especially sericite. These are in the form of aggregates, or felt-like intergrowths filling the spaces between the quartz, cyanite, and feldspar. The feldspar is plagioclase probably mostly albite. It is white, possesses good cleavage, and is one of the hard brittle minerals of the rock. It alters to kaolin, and sericite, and more or less of these alteration minerals are present within the feldspar crystals but not separated from them. The cyanite is of two varieties, distinguished by their colors as blue and white cyanite. The blue color varies in intensity, being a pronounced blue in some crystals and paler in shade in others. Some crystals have been seen which posses the blue color in one-half of their mass and are pure white or clear in the other half. The purity of the cyanite is probably not affected by the color, but it is difficult to detect the white cyanite in the ore by macroscopic examination, so that great care has to be exercised in the selection of the ore in the field. Of the above minerals, cyanite is the heaviest, having a specific gravity of 3.6; none of the others approach it in specific gravity. The usual as opiates of cyanite in the mica schists are garnet, magnetite, and tourmaline, but these have not been noted in the group of minerals treated, and their absence is a point of great value in favor of this ore, as they possess high specific gravities and interfere in separation processes, and if not separated they are detrimental because of their easily fusible character. Small amounts of apatite and titanite have been noted, but not enough to cause trouble.

Jan 1, 1931

By Charles Vaught, Henry J. Kellner, Michael J. Brnich, Henry P. Cole, William J. Wiehagen

In 1985, U.S. Bureau of Mines and University of Kentucky researchers began a series of studies relating to self-contained self-rescuer (SCSR) donning proficiency. During the next 5 years investigators examined a number of factors that have a bearing upon miners' ability to put on and use the apparatus in an emergency: the procedure being taught; availability and utilization of training models; opportunities to practice; hygiene; and on-the-job training. This report presents an overview of that research. It is concluded that companies should adopt a hands-on training protocol that allows them to integrate SCSR donning practice into other workplace routines such as fire drills.

Jan 1, 1993

By D. A. Stanley

The Bureau of Mines is investigating a method of dewatering flocculated fine-particle waste that involves treating the waste with a high molecular-weight polymer such as polyethylene oxide (PED) followed by dewatering on a static screen and/or in a trommel. Dilution of the polymer solution used for dewatering and use of the ion-exchanged form of the montmorillonite clay were found to be major factors determining the amount of polymer required to dewater clay-containing slurries. The amount of polymer, A, required to dewater ion-exchanged montmorillonite can be described by the equation, An = kC + b where n, k, and b are empirical constants and C is the concentration of the polymer solution used for dewatering. Clays that require large amounts of polymer for dewatering also dewater to a lower solids content. The concentration of the polymer solution is important because it affects the radius of the polymer coil in solution and hence its ease of transfer to a bridging configuration by shear. The constant, n, a function of the charge to hydrated radius of the exchange ion, relates to the strength of the bond between the polymer and the surface of the clay through a water bridge. The constant k is related to the hydrated radi-us for sodium or to the unhydrated radius for the other exchange ions.

Jan 1, 1986

By J. B. Gayle

Many investigators have reported studies of size distributions for particulate solids ; usually , these have involved the fitting of size distribution data to a particular mathematical function . Such studies are of unquestioned value and have contributed much worthwhile information regarding the breakage mechanisms for a variety of brittle materials . In connection with a Bureau of Mines study of the size distribution of coke , which has been subjected to the standard American Society for Testing Materials (ASTM) tumbler test , attention was focused on the relation between the 1 -inch tumbler index (usually considered to be indicative of the ability of coke to resist degradation by impact ) and the 1 /4 - inch tumbler index ( indicative of the ability to resist degradation by abrasion ) . Specifically , it was noted that for certain sets of data the correlation coefficients denoting the relation between these indexes were positive ; for other sets of data , these coefficients were negative . Preliminary consideration of this problem indicated that the usual interpretation placed on correlation coefficients was erroneous in this particular instance because the variables being correlated were necessarily related . The work described in this report was undertaken to clarify the interpretation of results of correlation studies for variables of this type .

Jul 1, 1960