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By James S. Browning

The Bureau of Mines conducted laboratory batch and small-scale continuous selective flotation tests of barite-fluorspar ores from two deposits near Marion, Ky., to determine the technical feasibility of recovering commercial grade fluorspar and barite concentrates. The lignin sulfonate-sodium fluoride method of floating the fluorspar successfully produced acid-grade fluorspar concentrates. Flotation of the barite from the fluorspar tailing using petroleum sulfonate collector yielded concentrates suitable for use in compounding oil-well drilling mud. The fluorspar and barite recoveries were about 82 and 85 percent, respectively.

Jan 1, 1963

By R. A. Guereco

Accurate measurements of physical dimensions of a section of stainless steel capillary tubing are presented and used to develop two final working equations for an absolute gas viscosimeter. The effects of pressure and temperature on these dimensions are considered. The internal surface finish and nonuniformity of the capillary bore are discussed, as well as entrance, kinetic energy, gas slippage, and gas compressibility correction factors.

Jan 1, 1967

By H. R. Babitzke

To develop alloys suitable for use at elevated temperatures, columbium and tantalum were combined with tungsten, hafnium, vanadium, zirconium, and titanium, and the resulting alloys were evaluated with respect to fabricability, hardness, Electrical resistivity, strength at elevated temperatures, oxidation resistance, and bend transition. Of the 23 compositions tested, Cb-2OHf-5W-10Ti exhibited superior high-temperature properties. A recrystallized sample of this alloy was fabricable at room temperature, had a strength of 44,000 psi at 1,200° C, and had an oxidation rate of only 7.7 mg/cm2/hr at 1,000° C.

Jan 1, 1966

By Oliver Bowles

"Conservation of slateWaste slate is a problem of outstanding importance in the slate industry, for a very large proportion of all slate quarried is thrown on the waste heap. While many uses for waste slate have been found, the demand calls for merely a fraction of the present supply of unused material. If the slate industry is to increase in prosperity, the producer's energy must be directed toward the development of ways and means of reducing waste to the lowest possible point. The Bureau of Mines of the Department of the Interior has devoted much study to this problem and a recent bulletin ** contains a detailed discussion of the waste problem.Attention has recently been directed toward an improved method of cutting slate in quarries, a method that promises to reduce greatly the percentage of waste material. The method has been introduced since that bulletin was published, and this supplementary paper covers the details of the process.A reversion in method,In connection with this new mode of operation history is repeating itself in a very interesting way, for the old quarry bar used years ago with steam drills, and later discarded in favor of the channeling machine .and the hammer drill, has been salvaged from the scrap heap, and again put to active use. The occasion for its employment is an attempt to improve quarry methods by the substitution of drilling for channeling or blasting."

Oct 1, 1923

By John C. Holtz

"INTRODUCTION Information on the gaseous products from the detonation of explosives has been obtained in two ways. In the first, the atmosphere in mines is analyzed after blasting, and in the second, the gases found after detonating an explosive in a testing apparatus are analyzed. The Bureau of Mines, in a cooperative research 3/ that compared data obtained in the field with those obtained in the testing station, showed that the results were not in entire agreement. The production of carbon monoxide was found to be governed chiefly by the oxygen balance of the explosive, but the production of oxides of nitrogen did not change in so simple a manner. Because of the increasing interest in correlations between the composition of the explosive and the production of toxic gases, it seemed desirable to continue the investigation.PURPOSE OF INVESTIGATIONAs field tests are both time consuming and expensive and as field results are affected by factors that are not always under control of or clearly evaluated by the operator, the purpose of this investigation is to develop a testing-station procedure that will reproduce the gaseous products quantitatively under known conditions analogous to those that may be expected in the field. In addition, the factors affecting the formation of toxic gases, particularly oxides of nitrogen, will be studied,"

Apr 1, 1940

By Richard D. Miller

This publication contains routine analyses and related source data for 350 natural gas samples from 19 States collected during calendar year 1362 as part of a continuous survey of the United States for occurrences of helium in natural gas. This survey has been conducted by the Helium Activity of the Bureau of Mines since 1917. The analyses published herein were made by mass spectrometer and a special helium analysis apparatus. Four previous publications have been made to present the results of 5,648 gas analyses made by the Bureau of Mines, Helium Activity, prior to 1962. The first, Bulletin 486, 3/ contains analyses and data on 2,195 gas samples collected during the period 1917-47. Bulletin 576, 4/ the second publication, includes data and analyses for 1,575 samples collected from 1947 through May 1956. The third bulletin contains 1,444 analyses and source data of samples obtained from May 1956 to January 1, 1961.

Jan 1, 1964

By Richard D. Miller

This publication contains routine analyses and related source data for 350 natural gas samples from 19 States collected during calendar year 1962 as part of a continuous survey of the United States for occurrences of helium in natural gas. This survey has been conducted by the Helium Activity of the Bureau of Mines since 1917. The analyses published herein were made by mass spectrometer and a special helium analysis apparatus. Four previous publications have been made to present the results of 5,648 gas analyses made by the Bureau of Mines, Helium Activity, prior to 1962. The first, Bulletin 486, 3/ contains analyses and data on 2,195 gas samples collected during the period 1917-47. Bulletin 576, 4/ the second publication, includes data and analyses for 1,575 samples collected from 1947 through May 1956. The third bulletin 5/ contains 1,444 analyses and source data of samples obtained from May 1956 to January 1, 1961.

Jan 1, 1964

By Oliver Bowles

Enormous quantities of limestone are used for metallurgical purposes. Approximately 23 million tons were so used in the United States in 1925 chiefly for smelting iron ores in the blast furnace. Smaller amounts are used in basic open-hearth steel manufacture, and in smelting lead, copper and antimony ores. Most limestone producers lave little knowledge of the way in which their stone is used in metallurgy. Maximum tolerances of silica, alumina, sulphur and possibly magnesium; and minimum content of calcium carbonate may be arbitrarily fixed for the guidance of the producer, but aside from these requirements little information is available to producers on the manner in which their stone is used, the office it performs in smelting, or the effects of impurities. More complete [wledge] of utilization would enable limestone operators to solve their production problems more intelligently.

Jan 1, 1927

By William Y. Mo

This Information Circular provides a detailed background documentation of how the Bureau of Mines projects U.S. mineral demand to the year 2000. These statistical projections serve as a quantitative basis for contingency forecasting of the low, high, and probable U.S. demand for nonfuel minerals by end-use categories and are published in the Bureau of Mines Mineral Commodity Profiles and Mineral Farts and Problems series. Aluminum is used as an example in this study.

Jan 1, 1980

By R. O. Dannenberg

Exploratory research was conducted to ascertain the feasibility of recovering beryllium from Spor Mountain, Utah, ore by the sodium fluosilicate (Na2SiF6) method used industrially for processing beryl. Na2SiF6 requirements to form water-soluble salts of beryllium were determined for three different samples--two clayey ores containing 0.6 and 1.3 pct BeO, respectively, and a calcareous ore containing 0.6 pct BeO. The ores were sintered with Na2SiF6 at 750° C for 3 hours. About 80 pct of the beryllium was rendered water soluble by sintering the 0.6-pct BeO ores with 30 and 40 lb Na2SiF6 per lb BeO contained in clayey and calcareous ores, respectively. The higher grade 1.3-pct BeO clayey ore required only 20 lb Na2SiF6 per lb BeO to solubilize over 80 pet of the beryllium. As the 0.6-pct BeO clayey ore was possibly the most representative of the deposit as presently delineated, leach liquor prepared from this sample was treated to recover beryllium salts. About 60 pet of the beryllium contained in the ore was recovered as beryllium hydroxide, which then was calcined to yield a 99-pct BeO final product by means of the following operations: (1) Sintering with Na2SiF2, (2) leaching with water, (3) precipitating crude Be(OH)2 by adding NaOH, (4) filtering to separate the hydroxide from the NaF solution, (5) redissolving the crude Be(OH)2 in excess NaOH, (6) filtering to reject caustic-insoluble impurities, and finally (7) boiling the Na2BeO2 filtrate from (8) to precipitate pure Be(OH)2. Reagent consumption was 49 lb Na2SiF6 per lb BeO recovered and 17 lb NaOH per lb BeO.

Jan 1, 1963

By J. M. Mutmansky, C. Lee

"Measurement of the size and elemental characteristics was performed on airborne coal mine dust samples collected by multi-stage cascade impactors as well as channel samples of the geologic materials. Size distributions were obtained using precise weighing techniques on the impactor substrates. Elemental analysis on the samples was performed by the proton-induced x-ray emission (PIXE) method, a rapid and non-destructive method of multi-element analysis.The various analyses were performed on 9 major and 21 trace elements. The results indicate the importance of intake air and shuttle car movements as sources of dust. The association of coal dust characteristics with channel samples was investigated using the coefficient of proportional similarity as a statistical measure. Results show a strong relationship between major elements and the geologic material being cut but a similar relationship between trace elements and geologic materials is not consistent.1. INTRODUCTIONThe most significant occupational disease in the coal industry is known ·as coal workers' pneumoconiosis (CW'P). While CW'P has existed for centuries, its mechanism of occurrence and association with coal dust has been well understood for only a few decades. In the 1930s, the significance of this disease led state and government officials in the USA to perform extensive epidemiological and environmental studies in the major coalfields. Study of these results plus later studies in the coal producing countries of Europe eventually led to the dust regulations that appear in the Federal Coal Mine Health and Safety Act of 1969.The impacts of the 1969 act were a productivity decline and increased production cost. Many analysts attributed this in large part to difficulties in complying with the new dust standards (Brezovic 1981). However, compliance was met in most continuous miner sections rather quickly. The remaining problem area is that of longwall mining where the procedures and layout of the minin~ system make it difficult to meet the standards."

Jan 1, 1989

By H. H. Schrenk

One phase of Bureau of Mines work in health and safety is promotion of the use of safe, satisfactory, and reliable respiratory protective devices. To insure that such devices will be. available, the Bureau has established schedules of minimum requirements for oxygen breathing apparatus,3/ gas masks,/ supplied-air respirators (hose masks, air-line, respirators, and abrasive blasting helmets, hoods, or masks),5/ and dispersoid (dust, fume, and mist)

Jan 1, 1943

The panic bars (and associated linkage's and electrical circuitry) that are defined in this document are a machine operator-actuated control for the emergency deenergization of the tram motors on Self-propelled, electric and diesel face equipment; including haulage equipment such as shuttle cars. There are nine basic types of panic bars (and several variations) that are recommended in this document, but all of the panic bars are characteristically of the "fire door" type that is frequently encountered on outside exit doors of many public and soma commercial buildings. It is also the intent of the following panic bar designs that, when emergency brakes are added to the face equipment machinery for which they are required, that they be designed and hooked up so that actuation of the panic bar will result in automatic application of the emergency brakes (immediately following the deenergization of the tram motors). The following panic bar design requirements are a restatement of the proposed requirements defined in the Federal Register, requirements cited in 'Guidelines for the Design and Installation of Devices for Deenergization of Self-Propelled Electric Face Equipment/Automatic Emergency Brakes" by C. E. Lester and J. D. Greenhalgh of MESA, and Bendix recommendations that were formulated as a result of discussions with personnel at the various machine manufacturers and underground coal mines that we surveyed, discussions with G. L. Judy (our consultant), etc:

Jan 1, 1974

The panic bars (and associated linkages and electrical circuitry) that are defined in this document are a machine operator-actuated control for the emergency deenergization of the tram motors on self-propelled, electric and diesel face equipment; including haulage equipment such as shuttle cars. There are nine basic types of panic bars (and several variations) that are recommended in this document, but all of the panic bars are characteristically of the "fire door" type that is frequently encountered on outside exit doors of many public and some commercial buildings. It is also the intent of the following panic bar designs that, when emergency brakes are added to the face equipment machinery for which they are required, that they be designed and hooked up so that actuation of the panic bar will result in automatic application of the emergency brakes (immediately following the deenergization of the tram motors). The following panic bar design requirements are a restatement of the proposed requirements defined in the Federal Register, requirements cited in 'Guidelines for the Design and Installation of Devices for Deenergization of Self-Propelled Electric Face Equipment/ Automatic Emergency Brakes" by C. E. Lester and J. D. Greenhalgh of MESA, and Bendix recommendations that were formulated as a result of discussions with personnel at the various machine manufacturers and underground coal mines that we surveyed, discussions with G. L. Judy (our consultant), etc:

Jan 1, 1974

A new horizontal borehole packer for use in coal beds has been developed. This packer utilizes a principal of operation which has not previously been used. The resulting packer is less costly to purchase, can be easily repaired in the field with inexpensive expendable parts. This report describes the development and testing of the new packer and the evaluation of commercially available packers.

Jan 1, 1971

By D. Harrington

Although the hysteria. with regard to silicosis end other occupational diseases seems largely to haws passed, and more careful sober consideration is being given this subject, it would be very poor policy for any employer to take the stand that the storm has blown over and that he can safely relax and revert to the status of 5, 10, or more years ago in such matters. The real fact is that occupational-disease compensation is nor in its infancy and can be expected to grow by leaps and bounds. At present, while 46 States of the Union3/ and the District of Columbia have compensation acts, only the following have some fern of occupational-disease legislation: California, Delaware, Connecticut, District of Columbia, Illinois, India a, Kentucky, Massachusetts, Michigan, Minnesota, Missouri, Nebraska, New Jersey, New York, North Carolina, North Dakota, Ohio, Pennsylvania, Rode Island, Washington, West Virginia, and Wisconsin. Silicosis appears to be compensable under those acts in California, Connecticut, District of Columbia, Illinois, Kentucky, Massachusetts, Missouri, New York, North Carolina, North Dakota, Ohio, Pennsylvania, West Virginia, and Wisconsin; possibly it may be interpreted as compensable in others. Occupational-disease legislation (largely relating to silicosis) has seen under consideration in some form relatively recently in Arkansas, California, Delaware, Idaho, Maryland, Kansas, Massachusetts, Michigan, Minnesota, Montana, Nebraska, New Jersey, Ohio, Pennsylvania, Tennessee, Utah, and. Washington at least. It will be surprising if comparatively broad or inclusive occupational-disease legislation will not be on the statute books of nearly every State in the Union within the next 5 years. With this situation confronting him, the far-sighted industrialist who has the best interests of his organization at heart will immediately begin to "put his house in order," if he has not already done so, by studying possible occupational-disease hazards to his employees; moreover, he will promptly apply all known remedial measures or will attempt to devise such measures if none of those already devised seem to apply to his establishment.

Jan 1, 1939

By Samuel P. Polack

This report reviews investigations to determine the fire hazard in coal mining when using flammable petroleum hydraulic oils to actuate mining equipment and summarizes research by the Bureau of Mines and industry on fire-resistant hydraulic fluids. Tests were established to evaluate fire resistance and the necessary characteristics to assure adequate service when fire-resistant fluids are used to replace petroleum hydraulic oils. The research was conducted in the laboratory and field trials under actual operating conditions in underground mines. Bureau of Mines Schedule 30 became effective December 17, 1959; the first approval was granted on February 18, 1960, and the twelfth was granted on March 17, 1961. The approvals include nine ready-mixed (by the producer) fluids and seven concentrates to which water is added by the user according to instructions from the producer. Seven synthetic-type fire-resistant hydraulic fluids submitted by two producers are also approved. Over 100 coal mines are now using water-in-oil emulsion-type fire-resistant hydraulic fluids in varying degrees from a trial in one machine to all the hydraulic equipment in an entire mine.

Jan 1, 1961

By R. S. Fowkes

A study was made by the Bureau of Mines of the penetration of selected granular materials in an unconfined state by wedge-shaped tools having dimensions comparable with the dimensions of the particles composing the materials. The output force for larger particles fluctuated radically. A custom-designed integrator was used to obtain work as a function of depth of penetration in the form of smooth curves. The influence of wedge angle, depth of penetration, penetration rate, entry angle, compaction state, and particle size on the force required and the work performed was ascertained. Empirical equations describing force and work as a function of penetration were obtained for each set of experiments.

Jan 1, 1973

By E. J. Gleim

A study of the records on file in the Bureau of Mines reveals that moray fire in coal mines have been started by electrical equipment or circuits. There the fires were of undetermined origin, electricity often was Strongly suspected as the probable cause. While it is unfortunate that positive evidence as to the cause is so often lost in the general destruction resulting from fires, there are many lessons to be learned from fire s in which the origin was definitely established as electrical. For modern high-speed methods of producing coal, electrically operated machinery has become virtually indispensable underground. With increases in the amount of equipment it has not always been necessary to increase the number of circuits in the mine where direct current is mainly used, but it has been necessary to increase the carrying capacity of these circuits. For example, lends such as heavy-haulage units drawing 1,000 amperes or more have brought boat the introduction of 6/0 and "No. 9 section" trolley wires. This has not made the task of fire prevention any easier, for it has meant that circuit breakers s must be set so high that partial short circuits fail to open them, therefore an arc of considerable proportions can be maintained without causing the, beaker to open. Thus, if as fall of roof brought a trolley wire down against a loaded car of coal, an arc might be struck that would ignite they cowl without opening the circuit breaker.

Jan 1, 1937

By Arne Landsberg

A study of the chlorination kinetics of germanium, silicon, iron, tungsten, molybdenum, columbium, and tantalum has been made to determine the effects of temperature, chlorine concentration, geometric surface area and gamma radiation. The reaction products were volatile at the temperatures used this making it possible to follow the reaction rates by weight loss of the solid. Chlorination rates of germanium, silicon, and iron were found to be directly proportional to chlorine concentration while the rates for tungsten, molybdenum, columbium, and tantalum were proportional to the 0.5 to 0.6 power of chlorine concentration. A good correlation of reaction rate and geometric surface areas was not obtained because the true surface area of the samples could not be measured. Intense gamma radiation had no effect on reaction rates. The Arrhenius activation energies determined over the temperatures used are as follows: Germanium, 27 kcal/mole (233°-241° C); silicon 33 kcaL/mole (375°-517° C); iron, cold rolled, 20 kcal/mGle (259°-325° C) annealed, 21 kcal/mole (293°-337° C); tungsten, 43 kcal/mole (617-776° C); molybdenum, 37 kcal/mole (445°-4910 C); columbium) 34 kcal/mole (229°?255° C); and tantalum, 29 kcal/mole (370°-449° C).

Jan 1, 1965