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By Albert L. Toenges

The introduction of mechanized mining in coal mines, which has speeded loading, has emphasized the importance of efficient underground transportation systems. The purpose of this investigation is to study and analyze various systems now in use, and to derive conclusions therefrom. This report may be helpful to operators who are planning new systems of transportation or who are revising present systems to increase their efficiency. This paper is the first of a series on this subject and des¬cribes some systems of transportation `utilizing rail haulage, ACKNOWLEDGMENT The information used in preparing this report was obtained through the courtesy and cooperation of the officials of the companies whose mines were studied. The descriptions of the transportation systems at the mines included herein have been checked for accuracy, and publication of the data has been approved by the executives of the several operating companies.

Jan 1, 1940

By G. S. McCaa

Rock-dusting is an. effective means of preventing coal-dust from propagating an explosion in a coal mine, but it will not prevent gas from igniting-explosively and with much attendant damage locally. Ventilation must therefore be effective at all times, regardless of the employment of other explosion-prevention methods, if gas explosions are to be avoided. This paper describes a gas explosion which occurred in as bituminous mine that was well rock-dusted at the point of ignition and which exemplifies the value of rock-dusting, the necessity of maintaining effective ventilation, and the need of permissible rock-dusting machines receiving power from a permissible locomotive. Description of Explosion The mine in which this explosion occurred is developed on a panel system in a practically level seam; the panel entries are driven in pairs, and the air current intakes on the right entry and returns on the left entry. Near the mouth of the intake a door is placed to control the ventilation; board stoppings are placed in crosscuts, except the second from the face, in which a brattice cloth curtain is hung, the last crosscut is left open and line brattices conduct the air current from the last crosscut to the faces. In No. 7 entry the last cross-cut was 152 feet from the face, the line brattice being within 38 feet of this face, and the second crosscut was 250 feet outby the face of the back entry or return. Seven days prior to the explosion the intake and return entries were rock-dusted to within 38 feet of the face, and as the entry had advanced during the week, the rock-dusting was to be extended.

Jan 1, 1929

By S. H. Ash

THE MAGNITUDE of the anthracite industry's drainage problem in the Lackawanna River drainage area is realized when it is known that in 1948 the 27 pumping plants in this region pumped over 48 billion gallons of water to the surface from the mines in the Lackawanna Basin of the Northern field. This is almost 92,000 gallons per minute pumped against an average hydrostatic head of over 300 feet for that year. By comparison, Lake Wallenpaupack, the largest artificial body of water lying wholly in Pennsylvania, contains 71 billion gallons of water in its 24-square-mile area: the volume of water pumped from the mines in the Lackawanna Basin during 1948 was approximately 68 percent of that impounded in Lake Wallenpaupack. The Lackawanna. River and its tributaries drain a troughlike area of 345 square miles. The synclinal axis of this trough lies within the coal measures. All surface drainage into the valley must traverse some part of the coal measures. On the basis of 45.03 inches of rainfall recorded by the Scranton station of the United States Weather Bureau for 1948, the runoff from the Lackawanna River drainage area during that period was 135 billion gallons, approximately three times the volume of water pumped by all mine pumping plants in the Lackawanna. Basin of the Northern field during 1948. In other, words because of the pervious condition of the strata overlying the mine workings, approximately one-third of the total runoff in the Lackawanna River drainage area becomes mine water. This report, reveals that less than 7 percent of the 72 miles of pervious stream beds examined between Archbald and Pittston have been unproved.

Jan 1, 1952

By J. E. Wilson

A bench-scale expansion tester using 71 grams of coal was developed to determine the practicability of an apparatus of this size to investigate the effect of variables such as oxidation, blending, bulk density, inerts, size consist, petrographic differences, and rate of heating on the expanding properties of coal. The value of this tester is shown by the correlation that exists between its results and those of the larger scale sole-heated oven expansion apparatus used in commercial plants. From tests on 32 coals the standard error of estimate for predicting sole-oven results from bench-scale results is ± 5.3 percentage points. A standard deviation of the difference between pairs of tests in the latter apparatus of ± 2.1 percentage points was determined for 31 samples. In the sole-heated oven test the expansion of a coal at constant pressure is directly proportional to the dry coal bulk density. Tests in the bench-scale tester show a similar relationship between expansion and bulk density. When the blending ratios of high-and low-volatile coals are varied, similar changes in expansion are observed in both the sole-heated oven and the bench-scale tester. Therefore, the effect of other variables on expansion should be similar in the latter apparatus.

Jan 1, 1960

By McHenry Mosier

The application of diamond drills for blast holes is limited to the special Job of extracting floor and stope pillars, and therefore their operation is intermittent. The zinc ore drilled occurs in metamorphosed dolomitic limestone. The mining method is sublevel open-stoping on 200- foot lifts. Ample fresh air is provided by mechanical ventilation. Diamond drilling blast holes began in August 1944. Drills were mount- ed on a 3-inch quarry bar. The contract price for labor for operating equipment owned by the company was $0.23 per foot. The diamond bits were cast-set at the factory in a sintered tungsten matrix. Bit replacement costs were $0.15 to $0.20 per foot drilled. The feet drilled per bit ranged from 87 to 258. The feet drilled per diamond-drill shift ranged from 121 to 129. Holes were loaded with 60-percent special gelatin dyna- mite and fired electrically. In percussion drilling, the estimated feet drilled por machine shift with hand-held sinkers was 65. The tons broken per machine shift averaged 40 throughout the mine. Detachable bits have been adopted recently. The principal advantage of diamond-drilling blast holes at the Balmat mino is the extraction in a safe manner of ore not minable by short-hole drilling. The principal disadvantago is the greater cost per foot of holo in comparison with percussion drilling.

Jun 1, 1947

By Robert C. Dyni

This U.S. Bureau of Mines (USBM) report summarizes a field demonstration of pneumatic backfilling technologies conducted at the abandoned Hillside Coal and Iron Slope in Vandling, P A. Researchers demonstrated two pneumatic backfilling technologies recently developed under the USBM's Abandoned Mine Reclamation Research Program, the Pneumatic Pipefeeder and the High-Efficiency Ejector. Both systems had previously been evaluated at the USBM's subsidence abatement investigation laboratory near Fairchance, P A. The objective of the demonstration was to fill 100% of the abandoned tunnel with backfill stone to prevent further subsidence. The Pneumatic Pipefeeder was used for 21 days, at a rate of 63 to 124 t/ d (69 to 136 st/d), to fill 88% of the tunnel. The High-Efficiency Ejector was used for 2 days, at a rate of 125 to 132 t/d (138 to 146 st/d) to fill the remaining 12% of the tunnel. The backfill placed by both systems was tightly compacted. The major problem encountered was wear on the polyethylene pipeline from the abrasion of the high-velocity backfill. The use of heavier steel pipe minimized the problem. A cost analysis for the entire project is given.

Jan 1, 2010

By William H. King

The property of the Cupric Mines Co. is situated in the San Francisco mining district, Beaver County, Utah, 21 miles westerly from Milford (fig. 1), the rail and supply center for the area. Scheelite mineralization was not discovered until 1941, although the occurrence of lead and copper minerals had been known previously. S. VI. Hobbs, of the Federal Geological Survey, examined the Cupric property in November 1941 and prepared topographic and geologic maps of the area. This work was supplemented by additional investigations in January 1943 and March 1944 (fig. 2).

Jan 1, 1949

By L. C. IlsLey

A list of permissible mine equipment, tested and approved p or to July 1, 1934, was published in Bureau of Mines Information Circular 6813/. The present list4/ includes virtually all the electric air compressors, coal drills, mining machines, loading machines, conveyors, mine pumps, room hoists, mine telephones, rock-dusting machines, switches, electric cap lamps, flame safety lanes, electric hand and trip lamps, electric flood lamps, methane detectors, blasting units, storage-battery locomotives, tandem locomotives, mower trucks, and concrete mixers tested and approved by the Bureau to January 1, 1937. The system under which these devices were tested permits the manufacturer, after his equipment has passed certain tests prescribed by the United States Bureau of Mines, to mark his equipment with a seal showing that it has been approved by the Bureau. These tests are designed to insure that equipments have the minimum requirements for safety in use. The only object of the bureau in making such tests and publishing lists of permissible equipment is to help decrease the hazards of mining.

Jan 1, 1937

By R. W. METCALF, A. G. Charles, F. M. SHORE

To furnish the information frequently requested by producers and suppliers as to the fuel requirements of the Federal Government , the Bureau of Mines , with the cooperation of the consuming departments and establishments , has collected the data herein , showing the Government's fuel consumption during the fiscal year ended June 30 , 1930. The following tables show the quantities and kinds of fuels consumed by the Federal Government in each of its departments and their principal branches , in each State , and in Alaska , Hawaii , Panama Canal Zone , Porto Rico , and the Virgin Islands . The separate departments and establishments were asked to supply information for each Federal building or other plant and , as to vessel fuel , the amount loaded at each port of supply . Fuels consumed in internal combustion engines are not included . The report does not include fuels used by Post Offices of the fourth class , since their fuels are not purchased by the Federal Government but are covered by an allowance in each case for light and heat . In some cases the data supplied represent receipts , which are approximately equivalent to consumption . The present study is believed to be the first effort to bring together the data representing the Government's requirements for the various fuels which it consumes . Figures showing the coal consumed by the Federal Government were gathered for the year 1922. These data are shown in an article by O. P. Hood and R. H. Kudlich of the Bureau of Mines , contributed as a chapter to " Industrial Coal ; Purchase , Delivery and Storage , " published by the American Engineering Council . The figures of coal consumption presented herewith are approximately comparable with those published for 1922 , a relatively small difference being due to the fact that the 1922 figures include the Philippine Islands and all other territory in which any coal was consumed by the Government . At the present time , the only data on Government fuel consumption that are published regularly are those compiled by E. B. Swanson , chief economist of the petroleum economics division of the Bureau of Mines . These are published annually by the Bureau of Mines in " Sources and Distribution of Major Petroleum Products , Atlantic Coast States , " and by the bureau in cooperation with the American Petroleum Institute in the annual " National Survey of Fuel Oil Distribution . " It is believed that the data herewith will prove of interest and value to the fuel industries as well as to Government consumers and that it will also afford a basis for measuring future trends in the use of the various fuels by the Federal Government . Figures showing the quantities of the various kinds of fuels consumed by each of the executive departments and independent establishments , are given in Table 1. It should be noted that when one organization procures and delivers fuel to be consumed by other branches

Apr 1, 1932

By T. N. McVay

The Bureau of Mines has developed a field test for detecting the presence of columbium in a variety of minerals containing the clement. The test consists of fusing the mineral or rock powder with potassium pyrosulfate in a porcelain crucible, digesting the melt with hot dilute hydrochloric acid to release the columbium oxide (Cb205), and subsequently reducing the columbium oxide to a lower oxide by adding tin, which gives a blue color to the contents of the crucible. The method will detect 1 percent of contained columbium oxide (Cb205) in a mineral sample provided no tungsten is present. If a mineral containing appreciable titanium is test,-!d in the same manner, the solution in the crucible becomes violet. In the presence of columbium, titanium at first causes a violet coloration of the solution, which after a few minutes is masked by the stronger blue of the reduced columbium oxide. Although tantalum oxide (Ta205) does not interfere with the columbium test, tungsten gives a blue color that is indistinguishable from the color obtained with columbium. A simple method is available to detect the presence of columbium in the absence of tungsten, but when the presence of tungsten is suspected, the sample must be subjected to somewhat more elaborate chemical tests to determine the presence or absence of columbium. Although these latter tests can be made in the field, several steps are involved that arc best performed in the laboratory with simple equipment.

Jan 1, 1962

By C. W. Owings

"Ventilation is one of the most important features of coal mining, and if a mine is exceptionally gassy it is often difficult to ventilate it in such a way as to make it safe. The general system of splitting the main air current so that two, three, or more sets of room entries are ventilated by the same current of air does not provide a safe method if non-permissible electrical equipment, such as cable-reel, crab-reel, or trolley locomotives are used on gathering haulage, or if open-type hoist or pump motors are used. The problem has been greatly simplified at the Crucible mine of the Crucible Fuel Co. at Crucible, Pennsylvania.The system is not only applicable to the room-and-pillar method of mining, but it may be adopted for any panel system of mining. There also appears to be a definite application in mechanized mining, where the rapid extraction often results in inadequate attention to ventilation and where the gassiness of the section generally increases because, as compared to hand loading, the methane has less time to drain off. The system to be described should commend itself to coal-mining men.ACKNOWLEDGMENTSThis investigation was made possible through the courtesy of H. J. Nelms, general superintendent. E. M. Marshall, safety inspector, E. G. Sauers, assistant superintendent, and Thomas Mark, mine foreman, assisted in the collection of information."

Sep 1, 1931

By Forrest T. Moyer

The National Safety Competition was inaugurated in 1925 by the Bureau of Mines, U.S. Department of the Interior, in cooperation with the Explosives Engineer. In the first nationwide contest, 210 mines and quarries were enrolled. In 1962, the thirty-eighth anniversary of the competition, 910 mines and quarries were enrolled. These participating plants were worked a total of 133,292,989 man-hours. Of the enrolled plants, 415 achieved injury-free operations for the year, the largest number of perfect safety records in the history of the contest.

Jan 1, 1964

By Forrest T. Moyer

The safety record of the coal-mining industry, both anthracite and bituminous, in 1966 was improved over that of 1965 in all general measures of injury experience. The improvement was more pronounced in the anthracite industry. The total of 10,679 disabling work injuries comprised 233 fatal and 10,466 nonfatal injuries, 26 and 692 fewer, respectively, than in 1965. The number of fatalities in 1966 was the lowest annual total since complete records were started in 1910. Similarly, the number of nonfatal injuries in 1966 was lower than in any year since 1930 when such data were first collected.

Jan 1, 1969

By L. E. Dalverny

This Bureau of Mines report describes the deployment, 5-month operation, and lessons gained from a continuous gas monitoring system using sampling-tube bundles at an underground mine fire in West Virginia. Research information gained indicates the utility of relating certain gas concentration ratios to events during fire development, mine reventilation, and mine recovery. In addition to monitoring the quality of remote fly ash seals, the system provided timely warning of dangerous gas concentrations which developed during surface and underground recovery activities. An evaluation of system components is supplemented by recommendations for improvements.

Jan 1, 1975

By R. A. Cortese

The U.S. Bureau of Mines has developed a flame-radiation-powered trigger device to explosively activate suppression barriers to quench gas and coal dust explosions. The major component of the device is a silicon solar panel, which converts radiation from the developing explosion into electrical energy to initiate an electric detonator, which releases an extinguishing agent into the advancing flame front. Solar panels that are rated to produce 20 W of electrical power when exposed to the sunlight are producing about 200 W when exposed to a full-scale dust explosion. The solar panel is electrically isolated from the detonator by a pressure-sensitive switch until the arrival of the precursor pressure pulse, which always precedes a deflagration. This combination of pressure arming and flame-powered photogenerator prevents false barrier activation and requires no external power supply.

Jan 1, 2010

By W. L. Crentz

Knott County is one of the smaller coal-producing areas in the Eastern Kentucky coal field. It contains numerous coal beds, many too thin to support mining over a wide area, Coal produced in the county is from a few rail-shipping operations and many small truck mines. Many smaller mines are working beds whose exact location in the coal-bearing strata is uncertain. Samples were collected from 11 different coal beds, of which the Fire Clay, Hindman, Upper Elkhorn No. 3, and Flag are the most import ant from a product ion standpoint. Known reserves in the Hindman bed. are very limited, and almost the entire production from this bed is gathered from two comparatively, large rail-shipping mines in addition to the four principal beds, samples were taken in the Francis, Haddix, Fire Clay Rider, Whitesburg, Amburgy, Upper horn No. 2, and Upper Elkhorn No. I .beds. Figure 1 is a typical section of the strata, showing the more important coal beds and. readily identifying their location with respect to each other. The bed names as shown are particularly important because of the local tendency to assign several names to the same bed. To avoid confusion, the names by which each coal bed is known also are given in the following listing. The coal. beds., in descending order, follow: [ ]

Jan 1, 1953

By H. Kato, G. Asai, R. Blickensderfer, R. Siemens

Some relationships were established among crystallographic orientation , rollability , deformation texture , annealing behavior , slip planes , and ductile- brittle bend transition temperature of molybdenum single crystals . Six large molybdenum single crystals obtained from an ingot melted by electron beam were oriented by X - ray diffraction and rolled on crystallographic planes of low indices in a known direction . During room temperature rolling , cleavage occurred on 100 type planes . At 300 ° C the crystals were rolled to 95- percent reduction in thickness . The crystals ( 001 ) [ 110 ] and ( 011 ) [ 100 ] were most easily rolled . Pole figures were used to correlate the deformation textures of the rolled crystals with the initial crystallographic orientation . Several of the textures which developed could be explained as a rotation about a < 110 > axis of symmetry . The cube crystal ( 001 ) [ 100 ] retained much of its " cubic " orientation . The (001 ) [ 110 ] crystal developed the simplest texture , whereas the ( 211 ) [ 113 ] and ( 211 ) [ 120 ] crystals developed the most complex textures . The 1 - hour recrystallization temperature of the crystal ( 211 ) [ 113 ] was 700 ° C , which is about 300 ° C lower than that of commercial polycrystalline molybdenum . The poles of the slip planes ( as determined from gross slip lines at relatively low magnification ) tended to lie within 20 to 60 degrees of the pole of the rolling plane . The Knoop hardness was slightly dependent upon crystallographic orientation but more dependent upon rolling direction . The ductile- brittle bend transition temperature was dependent upon the rolling orientation and the dislocation density .

Jan 1, 1964

By D. Harrington

Fine ventilation was discussed. much more 15 to 20 years ago than it is now, yet today there are tendencies in connection with ,-line ventilation (in fact, numerous ventilation systems have been installed in recent years) indicating that the lessons learned by bitter experience in the past either have been forgotten or lave not been brought to the attention of the present generation. Possibly, the mining min of today considers that conditions have changed so much that experiences of the past cannot be repeated today. At any rate, it seems desirable to restate some of the principles of mine ventilation that were understood more or less in the past and to call attention to some danger in connection with present-day trends or practices.

Jan 1, 1939

By C. A. Herbert

During the fiscal year ended September 30, 1932, there were 27 fatalities in the coal mines of Indiana. Four of this number occurred in small mines employing less than 10 men, over which the State Inspection Department has no jurisdiction. In addition to these coal mine fatalities, an explosives accident in a clay mine resulted fatally to one man. Tables 1 and 2, which follow, list the fatalities as to cause and occupation. Table 1. - Fatal accidents by cause, fiscal year ended September 30, 1932 [ ]

Jan 1, 1933

This Bureau of Mines report is a compilation of information on computer models of mineral commodity markets in the Federal Government, The directory was compiled by the Analytic System Working Group of the Interagency Minerals Information Coordinating Committee to support the formulation of policies related to nonfuel minerals.

Jan 1, 1984