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By P. J. McDonough

The Bureau of Mines designed and tested a hardware-software system for measuring on-line corrosion rates of materials in a rod mill in operation. Currents ranging from 10-6 to 10-3 A and potentials in I-mV increments were converted to a digital signal. The digitized data were frequency-modulated and transmitted from a rotating ball mill to an FM receiver, where they were decoded by computer and then processed in real time using assembly language software. This design approach would allow accurate measurement and control of systems where signals of small amplitude and large ranges are present.

Jan 1, 1988

By J. J. Pfeiffer, J. W. Myers, A. A. Orning

A study was made of the feasibility of using washery refuse in the manufacture of lightweight aggregate for building materials . Preliminary caking and burning tests showed that the refuse could be converted into lightweight aggregate but that refuse passing a No. 14 U.S. Standard screen could not be used without additional processing . The aggregate was prepared by pelletizing the refuse and burning out the carbonaceous material on a chain- grate in a refractory - lined furnace . A small stationary - grate furnace was used to study the process variables involved and establish optimum ignition and combustion conditions . Maximum ignition rates were obtained at air rates of approximately 200 lb per sq ft hr , but air rates of 450 or higher were required in the burnout period to obtain temperatures high enough to sinter the ash . The data obtained from this unit were used as a guide in the operation of the chain- grate furnace . In the chain - grate furnace , satisfactory results were obtained by using primary air rates of 200 lb per sq ft hr in the ignition zone and 500 lb per sq ft hr in the burnout zone . The ignition- zone air was preheated to 500 ° F , but the air for burnout was not preheated . A total of 2-1/2 tons of aggregate was prepared in this unit and made into experimental block . A commercial development based upon the results of this study yielded a product which met the ASTM specifications C 130-42 for lightweight aggregate , and blocks made from the aggregate were of good color , durable , and light - inweight .

Jan 1, 1964

This publication summarizes, for potential contractors and other interested parties, the proposed research, development, and demonstration contract projects programed by the Bureau of Mines for fiscal year 1977 (October 1, 1976-September 30, 1977) under its Advancing Coal Mining Technology program. The objective of these projects is to provide an ordered and sequenced series of advances toward the overall goal of providing the system technology required to increase the productivity of the coal mining process.

Jan 1, 1977

By F. X. McCawley

The Bureau of Mines, in pursuing its goal of extending the life span of strategic materials, conducted field corrosion studies at the East Mesa Known Geothermal Resources Area (KGRA) in the Imperial Valley, Calif., to determine the optimum materials of construction for use in geothermal mineral energy resource recovery plants. These studies included characterization of geothermal environments and in situ corrosion testing. The corrosion resistance of 10 alloys exposed to 5 brine and steam process environments was evaluated using the low-salinity, high-temperature brine from geothermal well Mesa 6-1. Of these alloys, Hastelloy C-276, Hastelloy S, Incone1 625, titanium-2nickel, and 316 L stainless steel had excellent resistance to corrosion in all of the process environments; E-Brite 26-1 and 430 stainless steel had fair resistance. Although general corrosion rates for 4130 steel and 1020 carbon steel were substantially higher than those of the other iron-base alloys, these two alloys could prove useful in low-salinity process environments because of their low cost. Aluminum alloy 5005 was the least corrosion resistant alloy and pitted severely. Scales formed on all of the alloys in every process environment. Calcite, aragonite, and an amorphous silicate were the major components of the scales.

Jan 1, 1980

By B. C. Parks

This paper is a report on the relationships between petrographic composition, chemical composition, physical properties, and thermal behavior of banded bituminous coal. It describes the relationships between petrographic composition, behavior in various laboratory tests, and carbonizing properties of different petrographic types of coal that occur in relatively thick benches in a single bed of high-volatile A bituminous coal - the Hernshaw bed of Boone County, W. Va. Thin-section microscopic analysis and free-swelling index determinations of the thin-section samples were made of a standard column sample. A standard face sample, a representative channel sample, and representative samples of two prominent petrographic benches of bright and dull coal were subjected to chemical analyses and free-swelling-index, plasticity, dilation, agglutinating, low-temperature carbonization, and BM-AGA retort tests. A float-and-sink separation was also made of part of the standard face sample. The fractions from this gravity separation were subjected to petrographic and chemical analysis and free-swelling-index, plasticity, and dilatation tests.

Jan 1, 1959

By Jr. Herty

As the problem of inclusions in steel has become increasingly important, more and more attention has been paid to the source of the oxide inclusions in steel. In killed steels the oxide inclusions are traceable to the reaction of deoxidizers with the iron oxide dissolved in the steel during the refining period of the open-hearth heat. In a large class of steel known as "rimming steel" the action of the steel during solidification depends entirely on the gas evolved, and this evolution in turn is controlled by the amount of iron oxide in the liquid steel in the mold. It is therefore of great importance to be able to determine the amount of iron oxide dissolved in steel and to devise methods for the control of iron oxide in any class of steel. The object of the present investigation was to obtain a true value of the oxygen con-tent of liquid steel. If the steel has not been deoxidized, the greater percentage of the oxygen is present as iron oxide in solution.

Jan 1, 1932

By A. Visnapuu

The Bureau of Mines has upgraded high-iron domestic chromite concentrates by a carbonyl process. The upgraded chromite concentrates show as much as 10 wt pct higher Cr203 content and up to a threefold in-crease in the Cr:Fe ratio, compared with the starting concentrates. The high-iron chromites were first reduced to convert the iron oxides to the metal, and then treated with CO at elevated pressures and low temperatures to convert part of the metallic iron fraction to iron pentacarbonyl. Carbonylation was accelerated by the addition of H2S in small quantities. The iron pentacarbonyl was extricated from the con-centrate in the pressure reactor during carbonylation by a CO sweep through a pressure-reducing valve and passed through a decomposer at atmospheric pressure to convert it back to iron metal and CO. CO pres-sure, temperature, promoter trends, and other factors enhancing iron pentacarbonyl formation are presented.

Jan 1, 1985

By Forrest T. Moyer

To keep the mineral and allied industries informed of trends in the causes of accidents and to point out the need for corrective measures, the Bureau of Mines collects, analyzes, and periodically publishes health and safety statistics. This report includes data for 1962 on injury experience, with related employment statistics, at coal mines in the United States. These data are presented in tabular form under the following: General Injury Experience Tables 1 to 6: Current data on number of injuries, degree of injury, frequency and severity rates, average severity, and related employment and production data by work location.

Jan 1, 1964

By Forrest T. Moyer

To keep the mineral and allied industries informed of trends in the causes of accidents and to point, out the need for corrective measures, the Bureau of Mines collects, analyzes, and periodically publishes health and safety statistics. This report includes data for 1962 on injury experience, with related employment statistics, at coal mines in the United States. These data are presented in tabular form under the following: General Injury Experience Tables 1 to 6: Current data on number of injuries, degree of injury, frequency and severity rates, average severity, and related employment and production data by work location.

Jan 1, 1964

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Jan 1, 2011

By R. D. Currie

Haulage accidents in the anthracite region cause fewer fatal and lost-time accidents per million man-hours than similar accidents in bituminous mines, a fact that may be accounted for in several ways, but primarily because haulage, in a large part of the region, is restricted to haulage crews operating only on the gangways where most of the miners seldom come in contact with movement or handling of cars and locomotives. Generally in underground mines the number of men injured compared with the number killed is greater for haulage than for roof-fall accidents, while the number of men killed by haulage is second only to the number killed by roof falls.

Jan 1, 1939

By Gustav Wafe

"INTRODUCTION The discovery in 1901 of ""gusher"" oil production at Spindletop, Tex., Tex., a salt-dome structure, led to exploratory drilling on other known domes and known domes and in areas contiguous to salt domes in the Gulf Coast region of Texas and Louisiana. Early drilling on the flanks of the domal structures disclosed incompetent 3/ shales, which flowed into the hole when attempts were made to drill through them. Often these shales seized the drill pipes and presented with equipment then in use, an insuperable barrier to deeper drilling. The obstructing incompetent shales came to be called ""heaving"" shales by drillers who attempted to drill through them. Formations of this type have hampered the penetration of the drill bit in many area in the Gulf Coast region to such an extent that the drilling of wells through heaving shale has become a major problem."

Mar 1, 1942

By Allen S. Smith

Analysis of the helium content of a natural gas presents more than the usual difficulties encountered in applying the thermal-conductivity method because of the relatively small amounts of this inert as present and the wide variation in the other constituents. However, the numerous advantages of this method and its adaptability to Continuously recording and control instruments make it worthy of consideration. A specific application of the method described yields quantitative results only when used with gas mixtures of known qualitative compositions which Vary within predetermined limits. Periodic analyses for the helium content of a producing gas well may be conveniently made by an absorption method, and a continuums analytical method is not necessary for this purpose. Natural gas containing 1.75 to 1.90 percent of helium produced from Government-owned wells is processed in the Amarillo (Texas) Helium Plant of the Bureau of lanes. The helium extracted in the plant is supplied to the Army and Navy, and the processed natural gas is sold to a commercial gas company. As complete recovery of the helium in the raw material is not economically practicable, the processed gas contains 0.1 to 0.3 percent of helium, depending upon conditions of operation. Production is checked against the helium removed from the gas, which before the installation of the thermal-conductivity apparatus was calculated from the analysis of a cumulative sample of the processed gas. As conditions of operation affect the residual helium content to a large extent, a composite sample was an uncertain index of the efficiency of the process.

Jan 1, 1934

By H. B. Brunot

The United States Bureau of Mines under provisions of Schedule 2C4 issues approvals covering complete operating units such as loading machines, room hoists, and storage-battery locomotives. Certain manufacturers design and build entire machines. Other manufacturers purchase a part or all of the electrical accessories from manufacturers of electrical equipment and make up permissible units by assembling them. Before the assembler purchases electrical accessories for use in such contemplated units he may require certain information from the accessory manufacturer as to whether the particular accessories are suitable for assembly in his proposed permissible outfit. To aid accessory manufacturers in marketing their product, a provision was incorporated in Schedule 20 whereby tests might be made on individual accessories and reports rendered as to the suitability of a given accessory for use in permissible assemblies.

Jan 1, 1935

By Sam S. Taylor, H. M. Smith

"INTRODUCTION In most oil fields, natural gas is the major source of energy causing flow of oil to the well. The amount of gas Produced with the oil generally exceeds actual energy requirements, so that in time the gas reserve of the field becomes seriously depleted and the oil production must be stimulated by some auxiliary means. One of these is to repressure the oil formation with natural gas; or, where a gas supply is not available, often air is used.Although P.ir is a Cheap and convenient repressuring medium, its use sometimes is attended with several disadvantages. First, the return air-gas mixture decreases rapidly in fuel value, often until it can be used no longer as a source of power. At the same time, explosive mixtures may result if recycling is used, causing hazards to life and equipment. Second, some fields experience considerable trouble with the formation of emulsions which become increasingly difficult to treat. Although there is no definite proof that air repressuring always causes these emulsions, many operators are convinced that this is the case. The Petroleum Experiment Station of the United States Bureau of Mines at Bartlesville, Okla., has been interested in problems connected with air-repressuring for a number of years. Some time was spent in studying the so-called ""bad gas""--return,mixture of low fuel value. However, it appeared impossible to attack the problem successfully from this angle, and an approach was made through a laboratory--scale study of direct oxidation of crude oil."

May 1, 1934

By Larman J. Heath

Preliminary results of an explosive fracturing-solvent injection heavy oil recovery experiment conducted by the Bureau of Mines at a shallow oil reservoir near Bartlett, Kans., are given. Three wells 35 to 50 feet apart were drilled to a depth of 360 feet, and an open hole interval from 300 to 350 feet in the Bartlesville Sandstone Formation was explosively fractured with 3,000 pounds of pelletized TNT in each well. Laboratory tests were made on cores obtained from these wells to confirm the suitability of using an aromatic-type solvent. Injection of a 74-percent aromatic solvent was begun into one well and continued intermittently for approximately 2 months. Crude oil production amounted to 29.6 bbl, or 11.7 percent of the total oil con¬tained within the three-well interwell zone.

Jan 1, 1972

By Richard J. Leary

The inputs of capital and labor to support future iron ore production were developed by the Bureau of Mines from projections of iron demand and estimates of capital and labor requirements. Trends in technologic change and the organization of production were analyzed. Labor requirement schedules for iron ore mining and beneficiating were constructed from aggregate inter-temporal trends and 1970 cross-sectional analysis of mines and mills. A sup-ply schedule of the capital requirement for mine-mill-pellet plants was developed from U.S. and Canadian experience. The structure of demand for iron to the year 2000 was examined as well as the availability of resources. Projections of capital and labor requirements to 2000 were constructed under two international patterns of iron ore supply to the United States. The most likely model is for a continuation of the 70 percent United States-30 percent foreign shares, expanding at an average 2.0 percent growth rate to 2000, and supported by a cumulative gross capital investment of $3.8 billion constant 1967 dollars and a labor force in the United States of 29,800 by 2000. The information content of projections is discussed, and the possible effects of international forces on supply are considered. A generalized methodology for estimating capital and labor requirements in other mineral industries also is included.

Jan 1, 1975

By Paul M. Ambrose

ADVANCES in mining and processing technology made it possible to reopen the De Beers diamond mine in South Africa, originally located in 1871 by Cecil Rhodes and closed in 1908. Radioactive material was used to indicate the efficiency of hydro-cyclones used in diamond concentration. Added interest was shown in recovering diamond from the sea off the coast of South-West Africa. Production of crude artificial abrasives declined because demand was paritally met by withdrawals from stocks. The value of graded grain-coated abrasives and grinding wheels surpassed those of 1962.

Jan 1, 1964

By Irving Hartmann, John Nagy

As part of a program designed to promote safety in industrial operations , the Bureau of Mines has been investigating the explosibility of numerous powdered products and dusts and studying means for the prevention of dust explosions . In a previous paper the results of a study of the inflammability and explosibility of metal powders were published . This report summarizes a similar study which has been made on various powders used in the plastics industry. The work was undertaken to provide information for a subcommittee of the Dust Explosion Hazards Committee of the National Fire Protection Association, which was charged with preparation of a code for the prevention of fires and dust explosions in plants producing or processing synthetic resins and molding compositions . The production of powders and generation of inflammable dusts are inherent in one or more steps of the manufacturing process of many resins and molding compositions, and control of the dust hazard is a major problem in the plastics industry . In the preparation of phenolic resin molding powders, for example , the solid synthetic resin is crushed and pulverized , and then blended with ground wood flour , cotton flock, or other fillers , as well as with coloring pigments . This raw mix is then passed through compounding mills , from which it emerges in the form of homogeneous sheeted stock, which is crushed , ground , and graded to form the molding powder . The number of major dust explosions in the plastics industry has been limited, but numerous small explosions have occurred, and in view of the ever -increasing volume of production the potential explosion hazard must be considered a very real one . Fortunately, this fact is realized by several manufacturers of plastic compounds , as well as by insurance companies , who are taking precautionary measures against possible accidents and during the past year or two have submitted numerous powder samples to the Bureau of Mines for explosibility tests .

May 1, 1944

By E. D. Gardner, Edmund Stein

"IntroductionMassive sulphides occurring in metal mines are inflammable and furnish the fuel for many mine fires. Actual sampling has shown that dangerous amounts of sulphur dioxide and hydrogen sulphide may occur in mine atmospheres after blasting in massive sulphides. Probably some .of the finer sulphide in the material being blasted burns while it is in contact with the flame from the explosion. It’s also possible that oxygen of the explosive enters into the reaction.That sulphide dusts are explosive under some conditions has long been suspected, but the theory has not been generally accepted as having been proved. Evidence now at hand appears to be conclusive that such explosions do occasionally occur in mine workings in massive sulphides. Information from several mines working in heavy sulphides shows that occasionally, sulphur dioxide in larger amounts than could be expected from the blasting alone are occasionally thrown out into the mine atmosphere during blasting. Accidents have occurred and lives have been lost by men being caught in such gases. Also it appears in a few cases that damage done to timber in stopes by concussions has been greater than could 112.ve been expected from the regular blasts. In most of these cases the unusually large amounts of Sulphur dioxide could only be accounted for by an explosion or by an ignition of sulphide dusts. When this occurs it is probable that the settled dust is stirred up by the first shot of a round, then the dust cloud is ignited by this or a succeeding shot.In one instance, the senior author, while wearing breathing apparatus, returned to a station to take a gas sample immediately after a raise round had been blasted, and encountered a heavy white fume or smoke that was corrosive to the skin and which forced a retreat. The sample, which was taken farther back in a greatly diluted atmosphere, showed a high percentage (0.18) of sulphur dioxide. The station and the raise which was just being started were very dry and the walls and floor of the station contained settled sulphide dust which apparently was ignited by the blast."

Mar 1, 1928