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By AIME AIME

THIS year's Chairman of the Institute of Metals Division is a relatively rare phenomenon in the metallurgical profession; he is an expert historian of metallurgy, he is a confirmed collector and student of old works on alchemy, chemistry, and metallurgy-vide: the famous Biringuccio and he is a profound student (with a somewhat idealistic slant) of recent trends in world affairs and in what some incurable optimists call civilization; and at the same time he is still possessed of a sense of humor. Incidentally he is also one of the bestknown nonferrous metallurgists in this country and abroad, and for fifteen years has been a willing worker in A.I.M.E and the Institute of Metals Division.

Jan 1, 1943

By Arthur B. Yates

DIAMOND drilling has advanced and expanded during the past few years. Along with this increase there has been a marked trend to rely more and more upon drilling for the outlining of ore for reserve purposes. This is especially true underground, where men have not been available for opening up ore by crosscuts, drifts and raises. During the recent heavy call upon known ore reserves, more drilling has been done for exploration and it has become expedient to drill longer lateral holes from underground and deeper holes both from surface and from exploration headings in the mines. Furthermore, these deeper holes have to be drilled closely enough to warrant calculation of "probable" if not "proven" ore, from the results obtained therefrom. Interpretation of diamond-drill results has become more precise and reliable with the growing knowledge and understanding of the geologic structures that control the geometry of ore distribution, and this has broadened the field of usefulness of the drill. All of this has created a necessity and a demand for more accurate control of the hole as to direction, a more precise and reliable method of surveying for position, and a need for better and more complete core recovery, as well as larger cores, to provide an adequate sample. At depth the control becomes more difficult and, at the same time, more important. CONTROL A close study of drilling in various parts of the world for a period of more than 20 years has brought to light one definite rule, practically invariable; namely, that diamond-drill holes tend to deviate into a position normal to any structure existing in the rocks, such as bedding, schistosity, gneissosity, or even parting or jointing-even if the hole is started at almost any angle other than parallel with the structure. It also appears that the better developed the structure is, the more quickly will the hole get into a position perpendicular to it. It has often been said that there is a tendency for holes to "drift" in the direction of rotation. This is obviously untrue, for in a vertical hole the measure of deviation would depend upon the azimuth chosen as zero, and there is an infinite number of choices. It has been proved, however, that in homogeneous rocks there is a tendency for the hole to corkscrew, and that the direction of the spiral is the same as the direction of rotation. This may account for the belief that holes drift in that direction. Some tests have been made using right-hand and left-hand rods, and these show that no matter what the direction of rotation the hole will swing into a position perpendicular to the structure. Methods of Control The foregoing empirical rule may be used as an indirect method of control. If the prevailing structure is known, it may be advantageous to start the hole as nearly normal to it as possible, for the nearer the direction of the hole is to this ideal, the straighter it will remain. This, of course, is not always practical and in some cases is impossible. Usually such a

Jan 1, 1946

By P. Schwed

IN determining the mechanism responsible for sintering, the most direct procedure available is the comparison of the observed time and temperature dependence of the process with the dependence to be expected upon the basis of each conceivable mechanism. This was done by Kuczynskil who, in treating the mechanism of surface diffusion, postulated, in effect, that the concentration gradient of vacancies is different from zero only within the neck. This procedure was recently questioned by Cabrera' who assumed, on the contrary, that diffusion occurs only in the region outside the neck. In the present note, the calculations are performed without restriction on the region of diffusion. To carry out this objective it is first necessary to

Jan 1, 1952

By R. E. Collom

VARIOUS chapters already written in the history of development of the North Dome of Kettleman Hills are monotonously identical in the one underlying theme of conservation of oil and gas. Discovered on Oct. 4, 1928, by Milham Exploration Co. with its wildcat Elliot No. 1, the field has been subjected to practically every modern form of produc-tion restraint in the name of conservation. The record thus far developed shows that conservation was had for a time, at a price; and that unitiza-tion must he blessed by single ownership or 100 per cent participation to be effective. In fact, incomplete unitization places a heavy handicap upon its participants in the competitive development that follows.

Jan 1, 1937

By Richard H. Terhune

Slag and matte, in lead and copper smelting, are, for convenience of removal, tapped into pots of small capacity, usually of paraboloid form, of cast-iron, weighing 275 to 300 pounds, and holding the same weight of slag. As in many smelting districts one ton of ore makes a ton and a quarter of slag, a large number of pots is needed to equip an ordinary plant. Sudden and frequent expansion of the solid bowl causes the pots to crack at the bottom in a few months, and the matte, a very fluid sulpliide, enters these rough fissures and speedily corrodes its way through the vessel. 1 find, from one year of practice with a slag-

Jan 1, 1887

RESOLUTION ADOPTED BY THE BOARD OF DIRECTORS AT ITS MEETING ON APRIL 17,1936 AND AMENDED ON MAY 21, 1947 Recognizing the fact that the problems of the committee named by the Board to prepare the "official ticket" for officers and Directors of the Institute are various and difficult, and desiring to assist this committee by setting forth some of the principles that should guide the committee and some of the qualifications that should be required of candidates, the following instructions are formulated and the Secretary is directed to publish them in MINING AND METALLURGY concurrently with the publication of the names of each newly appointed Nominating Committee and to send a copy to each member of the Committee

Jan 1, 1952

By R. A. Wyman

KYANITE schists in the Sudbury area have been generally described by Haw,1 who has also given particular information on preliminary treatment of three large samples from Dryden township, Ontario.2 Kyanite, garnet, biotite, quartz, and feldspar comprise the main ingredients of this ore. Kyanite is the valuable mineral. About 5 ½ tons of -35 +200 mesh product, made by dry rod milling, screening, and separation on the Exolon magnetic separator, were available for treatment by flotation. Magnetic separation had effectively reduced garnet and biotite so that flotation feed consisted essentially of kyanite, quartz, and feldspar, the kyanite content averaging 32 pct and representing about 86 pct of the kyanite in the original ore.

Jan 1, 1958

By D. M. McFarland

A FEW years ago a novel electric detonator known as the split-second or millisecond delay electric blasting cap was introduced for use in quarry blasting. Regular electric blasting caps fired in series may be depended upon to fire within a millisecond or so from the first to the last in a series. Regular delay electric blasting caps are provided that fire one period after the other period in intervals of 1/2 to possibly 1 l/2 sec. Most split-second or millisecond delays are designed to fire one period after the other period in possibly 25 to 50 millisecond intervals. The ear is not capable of detecting time intervals of this magnitude.

Jan 11, 1950

By Fred Prime

To an association like the one before which I read this paper, few questions can be more important and constantly recurring than the following, viz.: "What economy can be effected in the manufacture of American iron ?" And it is the one with which I purpose to deal in this paper; premising, however, that my object is merely to indicate the direction in which an answer should be sought for, rather than to give it myself. This subject may be divided into two parts; " Economy in the production of pig-iron," and " Economy in the manufacture of wrought-iron;" but it is to the former alone that I shall confine myself this evening.

Jan 1, 1873

By J. R. Billingsley

The Sunro mine, operated by Cowichan Copper Co. Ltd., under lease from Sunro Mines Ltd., a Cominco subsidiary, is located on the south end of Vancouver Island. Exploration and limited development before 1960 established the existence of twelve mineralized zones. The "B" and "C" orebodies of the River zone contained an estimated 937,000 tons of 1.80r/, copper plus approximately 35 cents per ton of precious metals. On reviewing the indicated tonnage and the exploration possibilities in the River zone and the other eleven zones it was decided to construct a 1500-tpd mill. In August 1961, excavating of chambers for a crushing plant and concentrator located underground near the River zone began.

Jan 12, 1963

By Frederick Prime

TO an association like the one before which I read this paper, few questions can be more important and constantly recurring than the following, viz.: "What economy can be effected in the manufacture of American iron?" And it is the one with which I purpose to deal in this paper ; premising, however, that my object is merely to indicate the direction in which an answer should be sought for, rather than to give it myself. This subject may be divided into two parts, "Economy in the production of pig-iron," and "Economy in the manufacture of wrought-iron ;" but it is to the former alone that I shall confine myself this evening.

By D’Arcy A. Shock, J. G. Davis

Continental Oil Co. has spent more than four years of research on the fundamentals of recovery of potash by solution mining. This work included laboratory investigations of salt solution, brine flow, selective extraction of KC1 from sylvinite, and control of cavity geometry. Laboratory results were expanded by means of a series of field tests, and subjects such as well completion and hydraulic fracturing were added to the investigation. Both single-well and multiwell mining systems were studied in the field work. This paper discusses one field test in which potash was solution mined from a thin sylvinite ore zone in the Carlsbad Potash Basin. A two-well mining system was used for this test.

Jan 1, 1970

By Richard T. Newcomb

Federal and utility industry research has largely ignored coal beneficiation techniques in the implementation of SOx control. This paper accepts the hypothesis that beneficiation cum scrubbing is the cheapest way for the vast majority of seams in the eastern coal provinces to comply with standards. Comparisons are based on point estimates of average beneficiation costs from a model of coal preparation (COBET) designed to simulate four levels of cleaning. The paper describes how economic theory can be applied to derive econometric supply functions from actual data on the geology of minable seams, washability and technical constraints. West Virginia is taken as an example of a producing region. Spatial supply functions are derived empirically from the engineering model simulations.

Jan 1, 1977

By C. N. Kravig

STANDARD raises at Homestake are 150 ft long. Raises of more than 150 ft, driven with the use of a cage and hoist, are considered long raises- some have been driven more than 900 ft. Long raises have eliminated the need for access drifts on each level when transfer and ventilation raises are driven. These timbered cage raises, 7x9 ft in cross section, include a rock compartment and a combination cage, pipe, and manway compartment. To prevent excessive weight on the timbers, 10x10-in. bearing beams are cemented into hitches cut in the rock at 150-ft intervals. The beams also hold back timber movement caused by daily drawing of rock through the rock compartment.

Jan 6, 1957

By Charles Fulton

The study of the condensation of zinc from its vapor was undertaken to shed light on certain problems encountered in large-scale electric zinc-furnace work recently conducted. It is a matter of common knowledge that one of the disadvantages of the arc type, electric zinc furnace, is the production of a large amount of blue powder and proportionately little liquid spelter, for, as stated by Stansfield,1 "A notable defect in the electric smelting of zinc ores is the difficulty experienced in obtaining the distilled zinc in the liquid state; when zinc ores are smelted electrically, very little liquid metal is commonly obtained, nearly all of the zinc being in the state of powder."

Jan 8, 1918

By Cyril Smith

A STUDY of the precipitation-hardening of copper steels1 led the authors to investigate malleable iron containing copper, for the low-carbon ferritic matrix in malleable iron should lend itself admirably to precipitation-hardening. It was soon found that in addition to rendering malleable iron susceptible to improvement by precipitation-hardening treatments, copper has another potentially useful effect as an accelerator of graphitization. Brief mention of these effects was given in a general paper by Lorig and one of the present authors2; the present paper gives further details on the graphitization and precipitation-hardening effects only. After the completion of this work a paper by L. Lykkin3 appeared, confirming the authors' conclusions regarding graphitization.

Jan 1, 1935

By Arthur Crowfoot

INTRODUCTION The principal object of this paper is to present data on the development of the revolving convex round table as a concentrator for the through 0.07-mm. slimes from the ores of the Butte district, although same brief notes on the earliest recorded use of this type of concentrating table in the ore-dressing plants of the Lake Superior region and of the Butte district are also presented. The revolving convex round table belongs to the class of concentrating tables known as film-sizing tables, these tables using the relative transporting power of a film, or thin sheet of water, as it flows over a quiet inclined surface, to separate the minerals of a sorted product.

Jan 8, 1914

By H. C. Brassfield, R. E. Fryxell, E. C. Duderstadt, E. A. Aitken, P. K. Conn

Permeation rates of hydrogen through are-cast tungsten were measured at temperatures from 1300" to 2600°C with hydrogen pressure differentials of 1 and 0.1 atm across isothermal membranes. Rates were nearly Proportional to square root of pressure, were inversely ProPortional to membrane thickness, and were temperature-dependent according to the equation: p = permeation coefficient in cu cm (stp)-mm per sq cm-min-atmlr2, R = gas constant in cal per mole-OK, T = absolute temperature in OK. Permeation rates of oxygen through tungsten were deternlined in the range 1965" to 2300°C and at calculated oxygen (02) pressures of 3.3 x 10-4 to 2.2 x at?n using sealed capsules containing Kmown quantities of tungsten oxide. Permeation coefficients obtained in this manner had a temperature dependency in the range of 40 to 45 kcal per mole of permeating species. Permeation coefficients for oxygen were higher than those for hydrogen in the temperature range studied. This is probably the result of oxygen solubility being much greater than hydrogen solubility at these temperatures at a gzven pressure. The purpose of this investigation was to determine experimentally the permeabilities of hydrogen and oxygen through polycrystalline tungsten at temperatures ranging from 1300° to 2600°C. Permeation rates of hydrogen through tungsten have been measured at temperatures up to 925°C,but no previous measurements have been reported for the temperature range covered in this investigation. Some diffusion measurements3&apos;&apos; and solubility measurements3 have been made for hydrogen at temperatures below 2200°C. No previous permeability studies of oxygen through tungsten are known to the authors; however, efforts have been made to determine diffusion rates5-&apos; and solubilities PERMEATION THEQRY Permeation has been defined by ortton" as the overall steady-state flow process from the gas phase on one side of a membrane or wall to the gas phase on the other side and includes the steps of adsorption, solution, diffusion, exsolution, and desorption; in a given temperature range, any of these processes may be rate-controlling. For diatomic gases, which dissociate prior to diffusion, the quantity of gas which permeates through a membrane or wall at a given temperature is directly proportional to the surface area of the membrane, the length of time of permeation, and the difference between the square roots of the pressures on each side of the membrane, and it is inversely proportional to the thickness of the membrane when diffusion-controlled, thus: q = total amount of gas permeating a membrane, p = temperature-de pendent permeation coefficient, A = area of membrane exposed, / = time, p i = gas pressure of high-pressure side, p2 = gas pressure of low-pressure side, d = thickness of membrane. When the surface reactions are not rate-controlling steps and the solution of the gas in the metal follows Henry&apos;s law, the permeation coefficient, P, is equal to the product of diffusivity and solubility. The permeation coefficient is also temperature-dependent according to the equation: Po = permeation constant, Q = activation energy, R = gas constant, T = absolute temperature. MATERIALS The tungsten materials used in this investigation were greater than 99.9 pct pure. The interstitial impurities ranged from < 1 to 50 pprn C, 7 to 35 ppm O, less than 15 pprn N, and undetectable quantities of hydrogen. Previous high-temperature studies of are-cast tungsten have shown that thermal treatment similar to that which the hydrogen permeation cells experienced reduces the carbon content from starting levels of 50 to 60 ppm to about 30 ppm. Metallic impurities were in the low (1 to 50) ppm range. The argon gas used in this investigation contained about 8 ppm N. None of the following gases were

Jan 1, 1968

By H. Margolin, A. Coucoulas

Fused alumina or silica crucibles were used as the containing vessel. X-ray powder photographs were taken with CrKcll radiation and the use of Straumanis type Norelco cameras of 114.6 mm diam. Crystallographic data for these compounds are shown in Table I. These results are in agreement with others of this series reported previousiy by Wernick and Geller.l The abnormally large atomic volume of Eu and Yb metal3 is manifested in EuAl2, and YbAl2, when one compares them with the compounds reported in Ref. 1. However, the behavior of Yb in the Ni compound is the same as that observed in Ni5Yb having the Cu5Ca structure.4 Thus, it appears that Yb has a valence closer to 3 only in the Ni compounds; i.e.. the 2s and Id electrons are lost to the conduction band.1,4 Europium in EuAl2 appears to have a valence closer to 2. In previous work.&apos; X-ray patterns of ingots of NdCo2 indicated a multiphase material with faint indication of the presence of a phase having the MgCu2 structure. It was thought that NdCo2 formed peri-tectically from the melt, resulting in a multiphase system when cooled under nonequilibrium conditions. An X-ray pattern of a sample from a melt cooled more slowly than in past work showed that the major phase was NdCo2. The lattice constant, Table 1, is in excellent agreement with the value one can predict from the data of Ref. 1. One of the other phases was identified as Co5Nd. The author wishes to thank J. H. Wernick for his guidance in this work, and D. Dorsi for the preparation of these compounds. &apos;J. H. Wernick and S. Geller: AIME Trans., in press. &apos;J. H. Wernick and S. E. Haszko: to be published. &apos;F. H. Spedding and A. II. Daane: Progress in Nuclear Energy, Series 5, Eds.: H. M. Finniston and J. P. Howe, McGraw-Hill Book Co., 1956. &apos;S. E. Haszko: to be published. &apos;J. H. Wernick and S. Geller: unpublished work. 6J. 11. Wernick and S. Geller: Acia Cryst., 1959, vol. 12, p. &apos;162. A reinvestigation of the lattice parameters of Ti-Sn alloys by the present authors has revealed consistently hiher c and a values than those obtained by Worrier. The difference is most pronounced in the c-parameters which are, therefore, used as a basis of comparison. This discrepancy was not due to air contamination, since precautions were taken to exclude this possibility. Specimens for Debye-Scherrer photograms were prepared by arc-melting 15-g buttons of Bureau of Mines titanium and 99.99 pct Sn, with compositions of 6, 8, 10, and 12 at. pct Sn. These buttons were forged under an oxygen-acetylene torch to 1/8-in. sq rods to produce relatively fine grained material. Scale and some surface were ground off, and the rods, after wrapping in molybdenum and titanium sheet, were vacuum annealed 15 min at 800 °C to remove hydrogen. Heat treatment of one of the samples at 875°C to produce ß and reveal a at the surface showed no surface contamination. Following the vacuum treatment, the specimens were wrapped in molybdenum and annealed for 1 week at 800°C under two atmospheres of argon. After water-quenching, the rods were ground so that the thickness tapered to 0.1 mm at the tips. The ground specimens were then recapsuled as previously and reannealed 1 hr at 800°C to remove cold work. The

Jan 1, 1961

By G. C. Wallick, J. S. Aronofsky

This paper presents an experimental verification of numerical solutions of the differential equation describing the transient flow of an ideal gas through a porous material including gas slip effects. Several experiments previously proposed by one of the authors are described together with the correlation of the experimental results with the numerical solutions. Excellent agreement is shown between experiment and theory, thus demonstrating the validity of both the basic assumption made in the derivation of the differential equation and of the numerical solutions of the differential equation. INTRODUCTION In a recent paper,&apos; one of the authors has discussed a numerical solution of the differential equation describing the unsteady flow of an ideal gas through a porous material. This paper was primarily concerned with the effect of gas slip on the flow behavior. In steady state measurements, Klinkenberg2 and others have observed that the apparent gas permeability Kn of a porous material may be expressed as a linear function of the reciprocal average pressure 1/P of the form, ka = b + m/P........(1) where the intercept b is a constant for a given porous material and the slope m is a constant for a given porous material-gas combination. Aronofsky1 assumed that Equation (1) could be used to describe transient flow if P was replaced by the average pressure in an infinitesimal volume element. A number of numerical solutions of the resultant differential equation were presented and specific flow experiments were proposed as a means of testing the numerical solutions. The purpose of the present paper is to describe the results of several of these experiments and the correlation of the experimental data with the results of the numerical analysis. Reference should be made to the previous paper&apos; for details of the mathematical and numerical analysis. EXPERIMENTAL PROCEDURE A simplified schematic drawing of the experimental apparatus is shown in Fig. 1. An 8.89 cm diameter limestone core of length L = 14.82 cm was mounted in a conventional rubber sleeve permeameter cell. The external sleeve pressure in this cell was maintained equal to 500 psig during all experimental tests, thus permitting only longitudinal flow through the core. One end of the core, X = L, was connected to an adjustable cavity of volume V as well as a pressure gauge or manometer. The other end of the core, X = 0, was connected to a Nullmatic pressure regulator which was in turn connected to a nitrogen cylinder or vacuum pump. In each experiment, the core and adjacent dead volume were charged with nitrogen to a uniform gas pressure P1. The pressure at X = 0 was then suddenly raised or lowered to a constant pressure P, and the resulting pressure buildup or pressure decline at X — L was recorded as a function of the time. The porosity + and the permeability constants m and b were determined using the transient method which was suggested by the results of the numerical analysis and which was described in the earlier paper.&apos; The following average values for these constants were obtained as a result of 19 separate evaluations: 171 -0.259 2 0.005 md-atm; b = 0.374 5 0.008 md; and F = 0.098 ± 0.005*. It should be noted that in order that transient phenomena will be slow enough to be observed conveniently, it is desirable to use a porous material of very low permeability, e.g., less than I md. Moreover, it is in this low permeability range that the gas slip effects are most significant. Thus, such a low permeability sample is very suitable for use in an experimental verification of the numerical solutions previously described.

Jan 1, 1955