Search Documents

By Frederic A. Delano

The subject of the wear of rails seems to have attracted an unusual amount of interest in the last six months, and in the bope of doing my share to direct opinions in what seems to me the right direction, I will attempt to discuss briefly the several ways in which the shape of the rail-section may affect the life of rails. In a paper presented at the Boston meeting of the Institute (Trans., xvi., 594),

Jan 1, 1889

THE papers by G. F. Loughlin and I. A. Ettlinger discussed the distribution of formations and ore-bodies in two of the main mining districts of the Southwest. The convergence of the deeper orebodies at Cripple Creek points to their common hypogene ori-gin, as do the occurrences of the copper ores of, central Arizona. E. L. Bruce described the areas in southwestern On-tario around Red Lake and Woman Lake, another prom-ising gold district. Of special interest was a series of lantern slides showing the use of power-driven boats and of hydroplanes as means of transportation. Within a few years, no doubt; such devices will revolutionize the mining industry and reconnaissance mapping in these relatively inaccessible areas. Much interest was evinced in the paper by J. W. Finch on "Sedimentary Metalliferous Deposits of the Red Beds." It was written as a caution to people at-tempting to mine these deposits. The discussion of the chemical equations presented in the paper brought out the fact that a large amount of study of such ores is necessary before we shall be able to write equations to explain their formation. Especially pertinent were the discussions by David White as to the relation of decay-ing plant tissue to metalliferous deposits and the color of sediments; also the point brought out by T. S. Lover-ing that chemical compounds produced by bacteria may greatly affect the deposition and reorganization of sedi-mentary metalliferous deposits.

Jan 3, 1928

Discussion of the paper of Herbert F.. Miller, Jr., presented at the New York meeting, February, 1913, and printed in Bulletin No. 75, March, 1913, pp. 409 to 413. HENRY D. HIBBARD, Plainfield, N. J.:-Looking at the illustrations, it seems to me that a furnace made with the width of port that is shown here would not be a good working furnace. The economy of brick and gas might be all right, but I do not think it would melt the steel properly. I should say that the flame would not spread out suitably to fill the whole hearth of the furnace, and there would be undue waste, and it seems to me that it would be an undesirable furnace to adopt. The question as to whether a producer-gas flame would lie down in the furnace, hugging the bottom better than the natural-gas flame, is settled, not so much by the specific gravity of the gases themselves, as by the relative temperatures at which they enter the laboratory of the furnace. We know in that case that producer gas would be lighter than a natural gas which had not been run through a regenerator and expanded four or five volumes in consequence. I would like to hear what Mr. Miller has to say about the action of the flame spreading properly over the charge to give good metallurgical results in the form of furnace which he presents.

Jan 5, 1913

By Howard V. Sears

ArcHodrilling (Arcuate Hole Drilling) of short radius overhead curved holes from within the working level with a new, small-diameter in-the-hole drill produces tangible, assayable chip samples from the entire height of the projected mine level where the hole arcs down immediately in front of the working face. Drilling through the projected level with diamond coring tools produces samples showing the competence of roof and floor strata as well as the geological and economic characteristics of the ore. Hand-portable solid state electronic surveying instrument has been developed to survey the ArcHole and a convenient nomograph plotting record sheet converts survey digital readouts to hole inclination in degrees, to radius of curvature in feet, and to attitude of the plane of curvature from vertical in degrees, all without calculation. The ArcHodrilling system offers a tool with which the exploration geologist can more nearly assess the true potential of old mining properties being reexamined and to reduce the number of surface diamond drill holes needed to secure development data about new ore bodies. It gives the mine geologist an opportunity to secure those data at a fraction of the cost of drilling from the surface. The mining supervisor has a convenient, cheap tool to look ahead to know what he will be mining tomorrow. The mill supervisor has an opportunity to reduce his mineral loss in tailings by being able to anticipate the grade of his mill feed.

Jan 1, 1973

By Lester Blackner

THE PROPERTY AND LOCATION THE Ray Consolidated Copper Co.'s mining property is located on Mineral Creek 6 miles north of Kelvin, at Ray, Pinal County, Ariz. (Fig.. 1) . The mining claims now owned by the company consist of 126 lode claims, comprising 2,144.9 acres, containing at the beginning of operations 82,904,368 tons of 2.19 per cent. copper ore. GENERAL CHARACTERISTICS OF THE OREBODY The main orebody is a disseminated deposit in schist and porphyry formed by secondary enrichment. Its existence was proved by churn drilling, and it is at present one of the largest proved copper deposits in the world. The orebody itself covers .205 acres with an average thickness of 121 ft., and occupies a definite belt which has a northwest direction. Its length is approximately 5,000 ft. The width varies, being about 2,000 ft. at the west end and 2,500 ft. at the east, narrowing down irregularly front both ends to a few feet in the center. The thickness of the body varies greatly along the line of lode, ranging from a few feet up to 470 ft. thick. The ore horizon is not constant, but varies, following in a broad sense the topography The body in general dips slightly to the northeast, and is broken up by numerous small faults and fractures. The ore-bearing formations, consisting of mineralized schist and mineralized granite porphyry, stand fairly well and offer no difficulty in mining operations.

Jan 6, 1915

By R. L. Lloyd

UNLIKE the development of sintering lead, copper and zinc ores, the sintering of fine irony material had its birth, not as a result of gradual growth along lines aimed at the production of sintered and agglomerated product, but because the success of the sintering operation in other lines had been brought to the attention of the ironmasters, who were immediately attracted by the prospect of being able to convert their own fines-into a similar product. The abundance of iron ores in the United States and their comparative cheapness had led iron men into the habit of not paying particular attention to the fine material blown out of their blast furnaces. Hundreds of thousands of tons had been stacked up and used only during times of shortage of ore and then usually without any preliminary preparation, though many attempts had been made to briquette it. Briquettes proved good material, but the operation of briquetting was too expen-sive when applied to iron-ore fines. The development of the iron-ore blast furnace in the United States tended toward large units, high columns and heavy blast pressure, and this tendency is still peculiar to this country, whereas in the other countries the tendency has been to smaller units, lower columns and lower blasts. The high blast pressures and swift driving of the American blast furnace tend, of course, to produce more flue dust than European practice, and this production of flue dust was augmented when large quantities of soft ore, of which the Mesabi is typical, came on to the market. These ores are desirable chemically but physically they are soft, friable and fine, and when they are used in the iron blast furnace the flue dust produc-tion is increased. The necessity of rehandling the flue dust lead to briquetting on an extensive scale. The binders used were either chemical or mechanical, and in one system the briquettes were kiln fired in very high temperatures. Rotary kilns, coal or oil fired, were used extensively, and gave a product of hard and more or less nodulized material, but at considerable cost. This was the situation in regard to iron flue dust when the late James Gayley and his associates became interested in the idea of sintering the iron blast-furnace flue dusts under their own fuel (included coke dust) of which they carried between 15 and 30 per cent.

Jan 10, 1922

By W. H. Emmons

THE exploration of deposits of the metals will never become an exact science. There will always be an element of uncertainty in prospecting and developing mines. In countries where the surface has been closely scrutinized, most of the deposits whose outcrops contain valuable metals have probably been discovered. Many metalliferous deposits, however, are normally so much altered at the surface that the true significance of their outcrops is likely to be obscured. If a deposit is not exposed, its presence may become known by some one of its characteristics that is different in kind or in degree from a similar feature of the associated rock. Thus, a deposit that is not exposed may be discovered because of its magnetic property. So few minerals are strongly magnetic that the value of magnetic surveys is limited, but the dip needle has nevertheless proved of great aid in locating magnetic belts, and these in some regions are associated with workable iron ores. The Cuyuna Iron Range of Minnesota, which does not exhibit any outcrop of iron ore, was discovered by drilling "areas of attraction" that are due to belts of magnetic rocks associated with the iron ores. In some regions the use of the clip needle is justified, even if it does no more than reveal the strike of the rocks, since a knowledge of the latter enables the driller to locate and point his holes to advantage. The measures of gravity by the use of the pendulum are so accurate, or the limit of error is so small, that one might detect the presence of a concealed tabular deposit approximately at the surface, 34 ft. (10.36 m.) thick, having a density double that of the surrounding rocks. However, not many deposits have a density twice that of ordinary rocks and a thickness as great as 34 ft.; if they lie a short distance below the surface the density or the thickness must be even greater. Consequently, there is not much hope of sufficiently developing the gravity method of detecting deposits of heavy ores to make it of practical value. If the limit of error could be reduced to about one-tenth the present factor, and if the rather tedious and painstaking methods of determining gravity that are now in use could be simplified, the method would promise some degree

Jan 3, 1917

T. A. Rickard, Denver, Colorado: The observations made by the author concerning the treatment of gold-bearing ores, deal with the subject only briefly and in a general way; but, coming from an authority, they invite comment. In stating the fact that a " finely-divided condition " is a necessary characteristic of ores containing free gold, the author must be refer ring to those mining districts only with which he himself is ac quainted. The statement would not be true of certain gold-mining regions in America and Australia. The ores of some Californian mines and the mill-stuff treated at certain of the mills of Clunes and Ballarat in Australia, and of Otago in New Zealand, contain the gold in a free but in a coarse state. Moreover, "reduction to fine sand and flour" is not required by certain ores, even though the gold be in a finely-divided condition. In such cases the gold becomes de tached from the quartz before the gangue has been pulverized into particles as small as those in which the gold occurs. The dry-crushing of free-milling gold-ores is onknown in the new mining regions of the world. It is not clear whether the author has in mind any European district in which such a process is in actual use. If he has, a description of the method and the results obtained would be very valuable. Dry-crushing is, other things being equal, twice as slow and twice as expensive as wet-crushing. In the case of free-milling gold-quartz it serves no purpose, since such ore does not carry sulphides which contain any large percentage of value, and which, by being slimed, may carry away part of that value. The dry-crushing of a free-milling gold-quartz would be considered an absurdity by an American metallurgist. If the ore contain "free gold only," why submit it to a further treatment, such as concentration, after its passage over the amalga mating-plate ? What does the author propose to concentrate ? Again, why anticipate the treatment of tailings by the McArthur Forrest, or some other process ? The satisfaction felt by a mill-man in saving gold by a subsequent treatment of the tailings from his mill appears to me to be like that of the man who shoots at a rabbit,

Jan 1, 1894

By W. H. Emmons

The exploration of deposits of the metals will never become an exact science. There will always be an element of uncertainty in prospecting and developing mines. In countries where the surface has been closely scrutinized, most of the deposits whose outcrops contain valuable metals have probably been discovered. Many metalliferous deposits, however, are normally so much altered at the surface that the true significance of their outcrops is likely to be obscured. If a deposit is not exposed, its presence may become known by some one of its characteristics that is different in kind or in degree from a similar feature of the associated rock. Thus, a deposit that is not exposed may be discovered because of its magnetic property. So few minerals are strongly magnetic that the value of magnetic surveys is limited, but the dip needle has nevertheless proved of great aid in locating magnetic belts, and these in some regions are associated with workable iron ores. The Cuyuna Iron Range of Minnesota, which does not exhibit any outcrop of iron ore, was discovered by drilling "areas of attraction" that are due to belts of magnetic rocks associated with the iron ores. In some regions the use of the dip needle is justified, even if it does no more than reveal the strike of the rocks, since a knowledge of the latter enables the driller to locate and point his holes to advantage. The measures of gravity by the use of the pendulum are so accurate, or the limit of error is so small, that one might detect the presence of a concealed tabular deposit approximately at the surface, 34 ft. (10.36 m.) thick, having a density double that of the surrounding rocks. However, not many deposits have a density twice that of ordinary rocks and a thickness as great as 34 ft.; if they lie a short distance below the surface the density or the thickness must be even greater. Consequently, there is not much hope of sufficiently developing the gravity method of detecting deposits of heavy ores to make it of practical value. If the limit of error could be reduced to about one-tenth the present factor, and if the rather tedious and painstaking methods of determining gravity that are now in use could be simplified, the method would promise some degree

Jan 1, 1918

By E. V. Given

In speaking of the concentration of oxidized lead ores at St. Anthony, I do not wish to infer that we believe all lead ores of a similar grade can be mined and treated at a profit. Our oxidized ore is low grade, and certainly the mine under present economic conditions could not operate on this ore by itself. Because of favorable conditions we can operate the oxide circuit at a small profit although we do not allocate overhead, pumping, and certain other general charges to it. Operations in the oxidized zone were started as an essential part of the development necessary to outline and mine the sulphide ores. Nearly all of our oxidized lead ore comes from the Collins section of the mine, with the transition from oxide to sulphide ore lying between the 600 and 700-ft levels. Production from sulphide ore is much larger than from the oxide, both in tonnage handled and in grade of ore. The oxide and sulphide ores are never mixed either in the mine or the mill. The oxide mill sections have their own ore bins, grinding, and flotation departments. The lead minerals contained in the ore, in the order of their importance are cerussite, wulfenite, galena, anglesite, and vanadinite. The ratios of the different lead minerals change as the ore is pulled from different parts of the mine-total lead being approximately 50% to 60% cerussite, 20% wulfenite, 15% galena, zero to 10% anglesite, and 2% vanadinite. About 3% of the lead was unidentified.

Jan 5, 1950

By Clifford Wilson

SCREENED pipe is designed with the view of restraining the fine, free-running sands of the production zone from entering oil wells. Its successful use is dependent on a number of factors. The nature and effects of some of these factors can be determined through experiment and observation, but some of the elements that have a distinct bearing on the use of screened pipe can be evaluated only by estimate. The important subsurface conditions which affect the use of screened pipe are: 1. Depth of production zone. 2. Extent of production zone. 3. Reservoir pressure. 4. Character and relative quantity of oil and gas. 5. Character of sediments a. Consolidation of beds. b. Variation in beds. c. Grain-size gradation of sands. d. Free-running characteristics of sand from different levels. Aside from the use. of mechanical equipment and tools, the measures to be taken in the installation of screened pipe involve: 1. Size of liner. 2. Length of liner. 3. Design and mesh of screen. 4. Portion of liner to be screened. 5. Manner of setting liner. 6. Preparation of or washing of the well before or during the setting of the screen. 7. Manner of bringing in the well. 8. Manner of flowing the well. Values applicable to the actual subsurface conditions that exist at any well can only be approximated. The accuracy of the estimate will be measured by the amount and quality of the evidence at hand and the personal factor of ability to interpret the evidence fairly, whether

Jan 1, 1932

By Clifford S. Wilson

ScReened pipe is designed with the view of restraining the fine, free-running sands of the production zone from entering oil wells. Its successful use is dependent on a number of factors. The nature and effects of some of these factors can be determined through experiment and observation, but some of the elements that have a distinct bearing on the use of screened pipe can be evaluated only by estimate. The important subsurface conditions which affect the use of screened pipe are: 1. Depth of production zone. 2. Extent of production zone. 3. Reservoir pressure. 4. Character and relative quantity of oil and gas. 5. Character of sediments: a. Cossolidation of beds. b. Variation in beds. c. Grain-size gradation of sands. d. Free-running characteristics of sand from different levels. Aside from the use of mechanical equipment and tools, the measures to be taken in the installation of screened pipe involve: 1. Size of liner. 2. Length of liner. 3. Design and mesh of screen. 4. Portion of liner to be screened. 5. Manner of setting liner. 6. Preparation of or washing of the well before or during the setting of the screen. 7. Manner of bringing in the well. 8. Manner of flowing the well. Values applicable to the actual subsurface conditions that exist at any well can only be approximated. The accuracy of the estimate will be measured by the amount and quality of the evidence at hand and the personal factor of ability to interpret the evidence fairly, whether

Jan 1, 1933

By AIME AIME

THE Petroleum Division held a very successful meeting in Los Angeles, Oct. 4 and 5. The meeting was held on the eighth floor of the Chamber of Commerce building, the first day being devoted to technical sessions. Seventy-five members were registered before the opening of the first session. Glenn D. Robertson, vice-chairman of the local section, opened the meeting and introduced Edwin Higgins, managing director of the California Oil and Gas Association, who gave an interesting talk on the recently enacted gas conservation law in California. He explained that the law is an experiment which will be watched with a great deal of interest. The purpose of the law, which went into effect on Sept. 1, is to curb wastage and over-production of gas,

Jan 1, 1929

By W. Randolph Van Lewis

In determilling the relative rate and in fi~lding the point where different inlpurities containecl in copper-matte are eliminated during the process of a converter-blow, the follo~ving results were obtainecl : A converter was selected which was starting on its sccolld charge. The first charge after lining had finished its copper " hot," and conseqaently no copper was adhering to the sides of the lining. All the copper and granulated slag from the previous charpc mcrc dumped, thus removing ally possibility of " salting " the matte to be tested. The coliverter worked fast and well during the entire test. Periods of ten minutes were selected. The converter mas brought from the stack to secure each sanlple of matte to be

Jan 1, 1904

By J. F. Labuz

Fracture tests were conducted on subsize specimens of Charcoal granite to demonstrate that the extent of the nonlinear region at the crack tip can be significant. The model of the fracture process considers an effective crack length as a traction free portion plus a process zone where closing stresses act; this zone is identified by microcracking and interlocking. A singularity is allowed at the effective crack tip. The effective stress intensity factor is the superposition of the stress intensities due to the effective crack and the process zone. By assuming that the closing stress is a linear function, it is shown that a process zone length of approximately one-third the effective crack is needed to match the compliance-determined crack length.

Jan 1, 1984

By Ralph H. Sweetser

When a furnace-manager is '(blowing in," he generally has no time to consider the composition of the waste gas, and does not bother with it, except to take care that he does not get " gassed." Moreover, the analysis of the gases while the wood is still burning has not much to do with the economy of the normal working of the furnace; yet, on account of the deadly effects of the " blowing-in " gas when inhaled, and of its high explosive qualities, it is interesting to know its composition. In the Transactions there is no record of the analysis of the gas during an up-to-date " blowing-in." Even in Mr. Whiting's admirable paper (Trans., xx., 280) the reported analyses did

Jan 1, 1899

By Allen L. Hatch

Perhaps the greatest challenge to the non-ferrous extractive industry, aside from discovery and cost reduction, is the continuous effort toward the total recovery of metals. This is-and must continue to be-a joint endeavor on the part of the miner and the smelter, the first to trend constantly toward that form of concentration most amenable to the smelter and the latter to upgrade technical efficiency on the product delivered. What follows will be a smelter's-eye view of the relative value of gold, silver, copper, lead and zinc as they each are contained in copper, lead and zinc concentrates. The variety of combinations is obviously of such a magnitude that it will be necessary to restrict the observations to fundamental concepts.

Jan 1, 1966

By T. N. Andersen, K. J. Richards, C. N. Wright

The kinetics of the important reactions occurring in an electrowinning cell have been determined. This information has been used to quantify relationships between the operating variables of current density, solution composition, agitation, and temperature and the resulting current efficiency and deposit quality. Analysis of these results has shown (1) the importance of dissolved iron in determining maximum possible current efficiency and corrosion rate at the cathode suspension loop, (2) the role of agitation, current density, inert salts and temperature in*determining deposit quality and (3) the effects of non-uniformity in the hydrodynamic conditions from the bottom to top of the cell. The significance of the results of this study to the operation of a commercial plant directly treating acid leach solutions is discussed.

Jan 1, 1973

By John Vasey

A shaft of 1690 m depth is currently being sunk to exploit a large copper sulphide orebody. The primary crusher chamber, main pump chamber and the other excavations on the crusher level were developed from the shaft during the sinking operation. The maximum principal stress is horizontal and has a magnitude twice that of the vertical stress. It increased linearly with depth and on the elevation of the crusher level, 1613 m below surface, the stresses induced by mining can exceed the strength of the rock. The development of a workable crusher level layout, and a crusher chamber design and support system are described. Excavation and support of the workings are detailed and a comparison of expected and actual results is made.

Jan 1, 1983

THE sessions of the Institute were opened on Tuesday evening, October 26th, at Garrett's Hall, by Mr. Charles A. Otis, Chairman of the Local Committee of Arrangements, who welcomed the Institute to Cleveland, and introduced Col. Charles Whittlesey, who ad¬dressed the Institute briefly on the coal deposits of Ohio. Col. Whittlesey described the situation and character of the coal-beds of the State, and gave a short history of the use of raw coal in the manufacture of pig-iron, and spoke of the excellent quality of metal produced. The aid that a body of scientific miners and metal¬lurgists were capable of giving in the development of coal and other mineral resources was dwelt upon, and the hope expressed that the visit of the Institute to Cleveland might be profitable as, well to its members as to the citizens of the State. The President, Mr. A. L. Holley, responded to the welcome of Mr. Otis and of Col. Whittlesey, and read an introductory address on Some Pressing Needs in the Iron and Steel Manufacture. The following members and associates, duly proposed and indorsed by the Council, were then elected MEMBERS. Alfred S. Bertolet, - Youngstown, Ohio. Henry Binnse, - Chicago, Ill. John Birkinbine, - Philadelphia. Andrew A. Blair, - Watertown Arsenal, Mass. Ogden Bolton, - Canton, Ohio. Lloyd Booth, - Youngstown, Ohio. E. Borda, - Philadelphia. N. P. Bowler, - Cleveland, Ohio. Alexander E. Brown, - Cleveland, Ohio. C. F. Brush, - Cleveland, Ohio. S. M. Carpenter, - Cleveland, Ohio. James Cartwright, - Youngstown, Ohio. Henry Chisbolm, - Cleveland, Ohio. Wilson B. Chisbolm, - Newburgh, Ohio. W. H. Clarke, - Millertown, Pa. James E. Clayton, - Ore Knob, N. C.

Jan 1, 1876