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By C. E. MACQUICC

WITHIN a period considerably less than two decades, the engineering view of alloy steels has greatly changed-both as to their composition, and applications. Inasmuch as the elements used in manufacturing alloy steels are substantially the same as those which have been used for the past two or three generations, a statement like the foregoing may reasonably call for some explanation. The first commercial use of alloy steels in this country dates back to the sixties of the last century, when one of the earliest alloy steel patents, covering the use of chromium, was taken out by Bauer. About ten years later, German and French toolmakers began to introduce tungsten into tool steels. Developments along this line were more or less static for 25 years or more, the tool steel, compositions progressing along lines worked out by Mushet and one or two others in Europe. The next step in advance, made by Taylor and White inn the late nineties, consisted of heat-treating the alloy steels to enable much higher cutting speeds, thus introducing what soon became known as "rapid" or "high-speed" steels. All these developments being aimed toward the improvement of cutting tools, the compositions made were essentially of a hard, brittle nature. Following a different line of development started in the seventies, naval ordnance material began to embrace the nickel steels. These were rapidly popularized, became, and still are, with the addition of one or more elements, as chromium, molybdenum, vanadium, standard for heat-treated armor plate. During that period, however, no notable uses were made of alloy steels for engine parts or other high-stress parts where they are now considered indispensable; moreover, the present-day use of metals in the chemical industries was probably not even imagined. After the turn of the century, the necessity for making heavy-duty. machine parts, and especially the develop¬ment of the automobile, caused alloy steels to rapidly supplant plain carbon steels for engineering purposes.

Jan 1, 1930

By M Fuchs

Roadheaders were introduced to mining and tunnelling in the early-1960s. Since this period their main field of application has been for roadway drivages in coal mines and for mineral production, for instance in coal, rocksalt, potash and gypsum mines. Their main field of application in tunnelling is in softer and partly friable rock formations, a suitable area for non-blasting excavation. However, in longer tunnel sections excavators with high ripping forces have replaced roadheaders in many situations. The main arguments against roadheaders have been and still are:a sharp increase in excavation cost with increasing rock strength and increasing abrasivity; and greater risks in conditions which have not been, or could not be, investigated to a sufficient extent. These arguments have, to a great extent, restricted practical roadheader application in production mining and in a lot of æstandardÆ tunnel projects. To address these limitations, factors which could make roadheaders attractive for such conditions and could overcome existing technological difficulties have been investigated. Extension of the economic field of application in hard rock was found to be the most important and the most effective step forward.

Jan 1, 2002

By John Nagy

Dust explosion data obtained in laboratory tests by the Bureau of Mines are presented for 181 miscellaneous materials that present an explosion hazard. Data are given also for 50 dusts that present primarily a fire hazard and for 88 dusts that did not present an explosion hazard.

Jan 1, 1968

By Fernando Velazquez Guzman

Titanium is an alloying element used to refine grain size in steel and improve its physical and mechanical properties. In some stainless steels it is used to increase the resistance to corrosion by the precipitation of titanium carbides or carbonitrides. Its alloying performance is highly variable and depends largely on the stage of the secondary metallurgy process when it is added. Furthermore, the addition method (wire injection or direct addition) has a remarkable influence in secondary refining. This paper describes the tests performed in vacuum degasser (VD), with a highly compacted and encapsulated Ferrotitanium wire (FeTi HC). The yield of titanium in steel increased from 52% to 89%. Moreover, the consumption of the highly compacted Ferrotitanium was optimized.

Oct 30, 2017

By Vincent T. Ricca

Acid mine drainage is a serious water pollution problem, for its contaminants will eventually effect the quality of the receiving streams. According to the Appalachian Regional Commission (1969)1, 10, 500 miles of streams have been polluted by mine drainage, and 70 percent of this acid pollution is accounted for by underground mines. Due to the severe damage to aquatic life, to recreational and industrial use, and to domestic water supply, more stringent mining and anti-pollution laws have been legislated and coal mine operators are required to treat the mine water discharges to meet the minimum standards. For years now, abatement and treatment methods have been extensively studied. Progress reports presented in the Fourth Symposium on Coal Mine Drainage Research, 1972 1 suggest that a thorough investigation and understanding of the basin discharge is necessary in order to cope with the mine drainage problem. The extent of mine water discharge contamination can be considered as a function of the basin streamflow and acid generation load.' A conservative treatment cost estimation these days is $0.40 per 1, 000 gallons for water with 100 ppm iron, 500 ppm acidity. These figures need not include collection and pumping costs nor the cost of dispersing of chemical waste by-products. To achieve optimal abatement and treatment of mine drainage, predictions of the quantity and quality of mine water discharges are needed. Basin discharge is a continuous process and it can be considered as a. macro-system. This system can be subdivided into micro-systems to describe the various mine discharge .types in the basin. The mining activities could produce acid water discharges from deep mines, stripmines, or associated gob piles. A total study entitled ?Resource Allocation to Optimize Mining Pollution Abatement Programs?* will consider all of these sources. However, this paper will discuss only one micro-system, the drift (deep) mine type. We will look at a single mine and its watershed. The total research project considers a multiple mining complex in an extensive stream basin.

Jan 1, 1973

By Joseph Grumer

About a century ago Bunsen and his associates invented the famous burner that bears his name and was to become the ancestor of today's gas appliances. Over the years, Bunsen's invention became the starting point of a highly developed, practical technology that culminated in the gas industry as we now know it. However, it did not occur to the early workers to investigate the scientific potentialities of the new device, and as a result the science of gas-burner performance did not keep pace with the growing industry. It was with the objective of closing the rapidly widening gap between science and technology that the present research was undertaken Its immediate purpose was to provide basic information on the combustion characteristics of .fuel gases, in particular as they affect flashback, blowoff, and yellow tipping. Information obtained in the present research and contained within this report consists of the following: (1) Fundamental flashback and blowoff characteristics have been determined, it is believed, for all fuel-gas mixtures in which the gas industry may be interested. These are critical boundary velocity gradients for flames in free air, on burners with ports at room temperature and pressure. Burner aeration is characterized by the parameter, fraction of stoichiometric. These basic limits are explained, values are presented, and calculation procedure is given for deriving corresponding values of port loading and percent primary air (chs. I and II).

Jan 1, 1956

By Ellsworth Daggett

In the first paper on the Russell process presented by Mr. Stetefeldt, in May, 1884 (Transactions, xiii.), the process was treated from a purely theoretical standpoint.. 111 his second paper of October, 1886 (Transactions, xv,), the details of the plant, the chemicals used, and the manipulation in both mill and laboratory were treated. The aim of the present paper is to present economical results recently attained, new data affecting the preparation and manipulation of ore in the mill, and a more complete and systematic scheme of laboratory work. This paper is compiled mainly from Mr. Russell's notes of his own experience. Many of these notes, particularly those relating to work at Cusihuiriachic,* Mexico, have been upon work directly under the personal observation of the compiler, who takes pleasure in thus presenting to the Institute, data and considerations of much interest and value pot only to users of the Russell process, but to mill men generally. The description of the chemicals used and of the preparation of the mill-solutions being' in part the same now as when Mr. Stetefeldt's second paper was published, some use is here made of portions of that paper. No theoretical matter is here given. For a treatise containing also the theory of the process the reader is referred to Mr. Stetefeldt's complete work on " Lixiviation of Silver Ores by Hyposulphite Solutions," now in preparation. To facilitate the consultation of this paper, the following synopsis and index is prefixed. The figures in parenthesis indicate the page of this paper on which the subject is treated.

Jan 1, 1888

By M. W. Von Bernewitz

The Bureau of Mines receives frequent requests for information on the treatment of mercury ores, but as its own and almost all other publications on mercury are out of print, the Bureau has prepared this circular on the metal for the prospector and operator of small mines and plants. Mercury, commonly though improperly termed ?quicksilver?, is the only common metal that is liquid at ordinary temperatures. Mercury is used in the amalgamation of gold and silver, in power boilers, explosives, friction-less bearings, laboratory apparatus, lamps, medicine, paint, rectifiers, and for ?silvering.? The last mentioned is being superseded by silvering with silver. The use of mercury boilers may increase when they are thoroughly understood, but amalgamation is -being replaced to some extent by the use of corduroy and other collecting mediums, such as jigs and flotation cells.

Jan 1, 1937

By G. W. Adams

Foreword While the literature on radium is voluminous, there is no single publication available from Canadian sources which attempts to cover at all fully the world radium industry. The comparatively recent developments in the Wilberforce area, and the consequent arousal of public interest in radium, seemed to call for the publication of such a paper which would be intelligible to the layman. To satisfy this apparent need, the writers submit this paper which contains material derived from various sources, and for which the writers make no claim of originality. Direct references are made throughout the paper to sources of information.

Jan 1, 1931

By R. Bainbridge

THE cinnabar deposits of the Consolidated Mining and Smelting Company's Pinchi Lake property, situated near Fort St. James, B.C., were discovered and reported on by a Dominion Government geological party in 1937. Claims were staked by a group of local prospectors and, later, the Consolidated Mining and Smelting Company of Canada, Limited, took an option on the property. By the fall of 1939, exploration work had indicated ore of commercial quantity and grade, and laboratory tests had shown that standard methods of reduction, namely, roasting of the ore, followed by condensation of the mercury vapour produced, would result in satisfactory recovery. In June, 1940, construction of a 50-ton unit arranged for wood firing was completed and operation commenced. The installation consisted of a 46 in. by 60 ft. rotary kiln (see Figure 1) followed by a 14-in. Sirocco cyclone, a cast-iron condenser unit, and a 1,700 c.f.m. fan, exhausting to a stack. Other equipment included a 9 in. by 18 in. Denver jaw crusher with the necessary bins and feeders. As the need for mercury was urgent, because of war requirements, construction of a duplicate unit was begun almost immediately. This first extension started operation in January, 1941, and the plant was then capable of treating about 150 tons of ore daily.

Jan 1, 1945

By R. H. Harrison, D. R. Douslin

The thermodynamic properties H - H° , (H - H° ) /T , S - Sideal , S - S° Fide al F - F° , (F F° ) /T , and activity coefficient Y for perfluorocyclobutane were calculated as functions of temperatures ( 115.22 ° to 350 ° C) and molal density (0.75 to 6.5 moles / liter ) . Improved analytical and graphical correlating techniques are described .

Jan 1, 1964

By Ron H. Derammelaere

Coal Slurry Test Pipeline and First Recorded Commercial Pipeline Wallace Andrews founder of New York Steam Company awarded patent for ?Method of Transportation? that involved pumping finely divided coal in slurry form built test facility at Madison Avenue and East 58th Street in New York City died in 1899 in a fire and coal pipeline work was not continued First recorded commercial coal slurry pipeline designed by Gilbert Bell in 1914 to move coal from barges on the Thames River in London to a powerhouse in 8? tubes (660 yards long)

May 1, 2013

By S. G., Lasky

IT seems to be in the nature of concepts that they have many meanings, and that the meaning best reflecting the primary interests of a person tends to be accepted by him as the normal meaning of the concept. The concept of ore reserves is no exception, for there is no unanimity of meaning among the several groups of us who are interested in ore reserves, nor even among the individuals of a single group. The groups most interested in ore reserves would seem to include at least the mining industry, perhaps State taxing agencies, and the Federal Government in all its diversified activities, and I would include also the citizenry at large or at least that part of it that consciously thinks about problems-of national welfare. To each of these, and to different individuals within them, the term reserves represents something different, and the farther away the individual or group gets from physical contact with the ore, the more abstract does his or its concept become. It is something different to the policy maker from what it is to the fact-finder or to the miner.

Jan 1, 1945

By Kasimcan Koruk, Julian M. Ortiz

A geological model accounting for uncertainties possesses important advantages for resource estimation. Machine learning algorithms (MLAs) employed on multivariate geochemical datasets open up ways to new methodologies for such geological models with ease in comparison to traditional geostatistical methods. This article proposes a two-step MLA with an ensemble implementation to define geological domains and their uncertainties based on geochemical data. The proposed workflow is applied hierarchically on a dataset from a porphyry copper deposit to perform binary classification that can be attributed to alteration domains.

Mar 1, 2024

By Harold J. Schock

The cases of no auxiliary ventilation and ventilation with tubing were mathematically modeled, using a turbulent dispersion model. The scooptram that is used to load is modeled as a variable-speed, variable-strength source of pollutants moving in and out of the dead-ended drift. Model predictions are compared to experimental measurements. A parametric analysis was performed to determine the effect of exhaust pipe location and time spent out of the drift, as well as to determine if a relationship existed between CO2 and NO levels. It was concluded from this analysis that when modeling a load-haul-dump cycle, it is necessary to use a model that has the capability of predicting changes in source strength as well as source location. It was also determined that four relevant factors include effective heading height, apparent longitudinal diffusion coefficient, transverse concentration gradient at the face, and average dispersion width of the exhaust jet. As these factors change with heading geometry and ventilation configuration, they were determined experimentally, Carbon dioxide was used as a tracer to calibrate the model; since, knowing the fuel flow rate, it is possible to calculate CO2 production. The above four factors in the computer model were calculated using a regression analysis, comparing predicted local concentrations to measured local concentrations. The model was then verified after this calibration process using additional experimental results. With the calibrated model, it is possible to predict pollutant concentrations at any location in the heading using an engine map and the previously calculated flow field. A parametric analysis shows that the exhaust pipe location can have a significant impact on operator exposure to exhaust gases. It was also shown that NO concentration varies directly with C02 levels. Predictions using the dynamic model are contrasted with constant source strength (pollutant flow rate) results. An analysis of these predictions for computing time-weighted average NO shows the dynamic model predictions of operator exposure to this pollutant to be less than one-half of the value predicted using a constant source model.

Jan 1, 1981

By Fabiano Soares

Strand guide rolls in continuous casters are crucial components for guaranteeing an optimum process for the production of high-quality steel grades. The properties of these rolls greatly influence the quality of the slab produced. The most commonly used designs so far have been the axle roll and the solid roll. A quite new roll concept is the STEC-Roll®. It combines the advantages of the axle roll with those of the solid roll. This paper explains the development of this roll type and shows the current design. The characteristics of the STEC-Roll® are presented in greater detail and are underlined by a number of simulation results. Beside the design itself, the benefits for casting and maintenance are explained, including for example the easy assembly and dismantling or the use of the roll for dry casting. A brief examination is made of the TCO for the STEC-Roll® and an estimation is provided of the exchangeability of this roll. To conclude, an overview on the current applications is presented.

Aug 17, 2017

By T. A. Henrie, E. K. Kleespies

Carbon reduction of rutile and ilmenite in nitrogen and ammonia atmospheres was studied as a method of preparing titanium nitride . Ammonia was a better nitriding agent than nitrogen . The contact between the solid reactants , carbon and rutile , was a prime factor in nitrogen atmospheres and was of lesser import in dissociated ammonia . The reduction process for conversion of rutile to the nitride required carbon . The nitriding of ilmenite- carbon mixtures produced titanium nitride and elemental iron .

Jan 1, 1964

By W. K. Connor, O&apos

The Bureau of Mines is investigating the Co and Mn resource of the West-Central Arkansas District, including field investigations, mineralogical characterization, beneficiation, and hydrometallurgical tests. The deposits occur within the Ouachita Mountains and are con-trolled structurally, occurring along the axes of anticlines making up the mountain ridges. Brecciated novaculite is cemented with a mixture of Mn oxides, primarily cryptomelane and psilome-lane. Cobalt is concentrated within a particular Mn oxide phase, lithiophorite. Chemical analyses on head samples reported up to 25 pct Mn and 0.17 pct Co. Magnetic separation yielded products with up to 41 pct Mn and 0.22 pct Co at recoveries of 95 pct Mn and 93 pct Co.

Jan 1, 1991

By Thomas O. Llewellyn

This U.S. Bureau of Mines (US8M) report presents a concise review on sources, processes, supply, and historical use patterns of domestic cadmium. It also covers a preliminary estimated cadmium material balance for the year 1989.

Jan 1, 1992

By M John

The Kwinana Industrial Area (KIA) is by far the largest and most diverse industrial processing region (with supporting industries) in Western Australia. As with elsewhere in Australia (and globally), the KIA is facing sustainability challenges on various fronts, such as increasing water and energy scarcity, climate change, an aging workforce, and growing community expectations. Through the Kwinana Industries Council (KIC) the industries within Kwinana are working closely on common issues in the KIA, including the sustainable development of the region. Over the past decade, significant progress has been made by the industries towards the improvement of the sustainability performance at the company and regional level. Given the ever increasing sustainability pressures, there is strong desire to address sustainability challenges in the KIA, through a pro-active and collaborative industry approach. A sustainability roadmap is being developed to assist the KIC and its industry members with strategic decision making on the long-term sustainability of there. At the heart of the roadmap is a set of key performance indicators for each of seven priority themes or focus areas (water use, by-products produced, greenhouse gas emissions and energy use, economic performance, environment, community impacts and sustainable workforce). Aspirational targets and subsequent strategies are being developed for those activities where the KIC has an influence and can make a positive impact. The indicators and their targets enable constructive stakeholder discussions (eg with government and community) on emerging local issues and possible future directions for the KIA. The paper will report on the development process and the preliminary results of the sustainability roadmap for the KIA, including a historical perspective on milestones achieved so far and future aspirations.

Jan 1, 2009