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By R. I. Jaffee, F. C. Holden, H. R. Ogden, A. G. Imgram

The tensile and notch tensile properties of four refractory metals (molybdenum, tungsten, niobium (columbium), and tantalum) and one alloy (Mo-0.5Ti) were investigated. All the materials were evaluated in bar form, and the molybdenum and Mo-0.5Ti also were studied in sheet form. The notch sensitivity of each material was evaluated on the basis of several criteria, including the notch-unnotch strength ratio, the ductility transition, and the fracture transitions. USE of refractory metals as structural materials in aircraft and space vehicles may subject them to low-as well as high-temperature environments. At elevated temperatures, the usefulness of a material usually is limited either by strength considerations

Jan 1, 1962

By Schrade F. Radtke

The future of lead and zinc, as with any material, will relate directly to their capability to remain competitive; that is, to demonstrate cost-performance ratios that are superior to those of competing materials. These cost-performance ratios are not static; therefore, it is necessary to develop improvements in products or processes to maintain present markets or to penetrate other markets. Perhaps the surest way to achieve these goals, if they can be achieved at all, is through research. The world lead and zinc producing industry established ILZRO as its cooperative research function to carry on both fundamental and applied research and development efforts aimed at the stated objectives. Current research efforts in the fields of die casting, galvanizing, finishing, chemicals, architectural applications, ceramics, and batteries are reviewed and potential impact assessed, some projections are given of possible new areas of research. Environmental research and its impact on future uses of lead and zinc are also discussed.

Jan 1, 1977

By E. Miller, K. Komarek, W. Johnson

The activity of aluminum in solid Cr-A1 alloys has been measured by an isopiestic technique between Cr-A1890' and 1126" and 13 and 80 at. pct Al. The integral free energy of mixing has a minimum value of —5600 cal per g-atom at 59 at. pct Al. The maximum solid solubility of aluminum in chromium was determined to be 43 at. pct Al, and the composition limits of the compounds CrA14, Cr4A19, and Cr5Al, at 1000"~ were found to be 79 to 80, 66 to 70, and 59 to 63 at. pct Al, respectively. The thermodynamic properties of the Cr-A1 system have been investigated as part of a thermodynamic study of aluminum-transition metal systems.172 Little information is available on the equilibrium properties of the Cr-A1 system. The heats of formation of solid Cr-A1 alloys have been determined by Kubaschewski and Haymer at 600" and low-temperature specific heat data have also been obtained.~ More extensive work has been performed on the phase diagram, and a compilation has been provided by Hansen and Anderko,~ their phase diagram at elevated temperatures being essentially based on the work of Bradley and LU.~ The high-temperature portion of the phase diagram shows an intermediate phase CrA14 decomposing peritectically at 1018°C and existing at 82 at. pct A1 at 1000°C. They also identified the compounds with solubility limits of 72 to 75 at. pct A1 at 1000°C, and Cr5A1,, existing at 61 at. pct A1 at 1000°C. The maximum solid solubility of aluminum in chromium at 1000°C was found to be 46 at. pct Al. These elevated-temperature data were obtained by examination of quenched samples and were considered as less precise than the lower-temperature data. Koester, Wachtel, and Grube7 have revised the phase diagram as a result of their magnetic susceptibility and X-ray study. The results of this work differ appreciably from those of Bradley and Lu at temperatures above 800°C. The CrA1, compound is given as existing between 79 and 81 at. pct A1 at 1000°C, and they do not indicate the presence of a CrA13 phase reported by Bradley and Lu. They also report the compound Cr4Alg as having solubility limits of 66 to 70 at. pct A1 at 1000°C, while Bradley and Lu show this compound stable only up to 870°C. Koester et al. state that the high-temperature modification of the compound Cr5A18 is stable down to 1125"C, and not 980°C as stated by Bradley and Lu, and that the low-temperature modification of Cr5Al, has a range of homogeneity of 58 to 63 at. pct A1 at 1000°C. They also report that the maximum solid solubility of aluminum in chromium is 43 at. pct A1 at 1000°C. APPARATUS AND EXPERIMENTAL PROCEDURE An isopiestic method was employed which has been successfully applied to the determination of aluminum activities in solid ~e-All and Ni-Al alloys. Alloy specimens were held at different positions in a temperature gradient and were equilibrated with aluminum vapor from an aluminum reservoir kept at the temperature minimum of an impressed thermal gradient in a closed alumina system. Diffusion of aluminum into the specimens occurred until equilibrium was reached, at which the partial pressure of aluminum in each of the specimens was given by the vapor pressure of the pure aluminum reservoir. The activity of aluminum referred to liquid aluminum as the standard state in a given equilibrated sample at temperature T could therefore be expressed by: vapor pressure of pure aluminum at _ the temperature of the reservoir Vapor pressure of pure liquid aluminum, at specimen temperature T Since both the temperature of the aluminum reservoir and the specimen temperatures were determined experimentally, and the vapor pressure of pure aluminum is known as a function of temperature,' the activity of aluminum in a given aluminum alloy of known composition could be calculated. Initial runs were made with samples consisting of pure chromium chips placed in alumina crucibles. These runs exhibited large inconsistencies, indicating that equilibrium was not attained. High aluminum content Cr-A1 alloy powders were therefore substituted for the pure chromium specimens. The starting composition of the alloys was adjusted through experimentation until the concentration change necessary to attain equilibrium was small. In this manner, consistent results were obtained in reasonable times. SPECIMEN PREPARATION Alloy specimens were prepared from chromium of 99.997 pct minimum metallic purity: with 0.028 to 0.038 pct H, 0.0002 pct N, and 0.27 to 0.46 pct 0 (Aviquipo, Inc.). The aluminum had a purity of 99.99+ pct and the following impurities: 0.003 pct Cu; 0.002 pct S; 0.002 pct Fe; 0.001 pct Pb; 0.001 pct Ga (Aluminum Corp. of America). Alloy powders were prepared from weighed mixtures of chromium and aluminum by double-arc melt-

Jan 1, 1969

By Edward Keller

ALTHOUGH the subject matter contained in this paper is presented under a new title, its writing was induced by the work of S. Skowronski and K. W. McComas.1 A discussion of the latter is here combined with the presentation of new and independent data. The physical constants quoted by the authors of that paper, such as melting and boiling points, as also the chemical reactions of the substances involved, are so well established that the numerous confirmatory experiments and their application to metallurgical conditions leave little or no room for criticisms. On the contrary, they will greatly aid to dispel any lingering skepticism as to possible considerable losses of copper accruing when the metal is melted in the presence of its own and, probably, other chlorides and when no provision is made for the recovery of volatile products. Exception may be taken, to some degree, to that part of the work under the caption Melting Drillings of Copper Mixed With Sodium Chloride. These experiments should have been extended in order to make the implied reactions clear and the results convincing. The latter are stated to be, "that when sodium chloride is present above certain minimum quantity relative to copper some of it is found to volatilize in the melt while another part reacts with the metallic copper to produce the volatile cuprous chloride, and that When smaller quantities of sodium chloride are present the reaction is complete and all chlorine is found to have volatilized as cuprous chloride." Metallic copper and sodium chloride are mentioned as the sole reagents in this chemical process, acting, according to the authors, in a neutral atmosphere of carbon dioxide. The chemist, quite naturally, will inquire into the formula according to which that reaction takes place and find that it would present itself as follows: 2Cu + 2NaC1 = 2Na + Cu2Cl2 It would appear that the truth of this formula will be challenged and a more rational explanation of the reaction sought. Apparently, carbon dioxide is neutral relative to metallic copper in its molten state; whether it remains neutral in the presence of sodium chloride is quite another question. Does it not at that high temperature become an oxidizer and do not the conditions of the reaction change to those expressed in the following formula? 2Cu + 2NaCl + 2002 = Na2CO3 + CO + Cu2Cl2

Jan 9, 1919

Silver ore was first discovered in 1866 at Manhattan, and a few ore shipments were treated in a mill at nearby Belmont. The district was abandoned from 1869 to April 1, 1905, when rich gold float was discovered on what was to be called the April Fool claim. By early 1906, 4, 000 people lived in Manhattan. The San Francisco earthquake, in April of 1906, caused the withdrawal of capital from Manhattan and most of the mines were shut down. Later that year and in 1907, however, more strikes were made. The camp prospered until the mid-1920s, but a steady production of several hundred thousand dollars per year was sustained even during the great depression. Then, in 1939, Nevada's first bucket-line dredge was installed below the town and operated until 1947, producing $4.6 million in gold. The Houston International Minerals operation at Manhattan was started in July of 1980 at a throughput of about 545 mt per day (600 st per day). In contrast to the early day underground operations, Houston's mine is open-pit and processes low-grade disseminated ores. The ore is a metamorphic schist containing 2. 7 g Au and 1. 03 g Ag per mt (0. 08 oz Au and 0. 03 oz Ag per st). Some coarse gold, up to 1 mm in size, is present. Mining and haulage is done by a contractor. Stockpiled mine-run ore is crushed in three stages comprising a jaw crusher and two cone crushers, with screens ahead of the cone crushers. Crushed product, at about 19 mm (3/4 in.) size, is stored in a silo. Grinding is by single stage ball mill with the discharge passing over two hydraulic traps for coarse gold removal. These traps will be replaced in late 1980 by a two-cell Pan American jig treating the cyclone underflow. The jig hutch product, along with the hydraulic trap product that has been stored, will be treated further for gold recovery. The gravity tails will then be cycloned with the underflow being recirculated in the ball mill and the overflow being treated by flotation. A rougher concentrate is made in twelve No. 48 Galigher cells with the float tails being cycloned. Cyclone underflow is refloated in another four No. 48 cells; the overflow is treated in sluice boxes for further gold recovery before being sent by gravity to the tailings pond. Bulk flotation concentrates are cleaned three times with the final concentrate being thickened. The thickener underflow is then batch cyanided in mechanically agitated tanks and washed with barren liquor

Jan 1, 1981

By D. L. Albright, R. W. Kraft

High-purity materials have been used in producing as-cast, controlled, colony, and degenerate solidification structures in the Fe-FeS eutectic. Experiments disclosed that this eutectic can be classified as normal and has a natural morphology composed of rodlike iron particles dispersed in a matrix of iron sulfide. The metallography of the various structures was studied, and a preferred crystallography was revealed in the controlled specimens produced by unidirectional solidification. The orientation effects found in these latter specimens are an [001] fiber texture in the -mowth direction of the bcc iron bhase and a texture corresponding to bicrystalline behavior in the hexagonal iron sulfide, with the growth direction near to (2111) poles. The observed texture of the iron phase is considered as indirect evidence that the alloy un-dercooled by at least 75°C before solidification. The unidirectional solidification of binary eutectic alloys has produced materials which exhibit a structure and properties markedly dependent upon the solidification process. In many cases a controlled microstructure with pronounced metallographic and crystallographic anisotropy can be experimentally achieved by proper regulation and balance of the growth rate of the alloy, the chemical purity of the starting materials, and the thermal gradient in the liquid at the liquid-solid interface. The purposes of this investigation were to produce various micro-structures in the Fe-FeS eutectic for subsequent study of their magnetic properties and to correlate the different structures with the solidification conditions in order to obtain a better understanding of the structure of eutectics. The Fe-S equilibrium diagram exhibits a eutectic composed of nearly pure iron and stoichiometric iron sulfide (FeS1.00), with the eutectic reaction occurring at 988°C and 31.0 wt pct S.1 Calculations indicate that this eutectic should solidify with about 9.5 vol pct Fe and 90.5 vol pct FeS, which in turn suggests2 that the micros tructure will consist of a rodlike iron constituent dispersed in a matrix of FeS. This characteristic has in fact been revealed some years ago.3 Thus, controlled solidification of this alloy might yield a material whose micromorphology would consist of very small ferromagnetic iron particles, rod-like in shape and aligned parallel to one another, supported in a matrix of antiferromagnetic FeS. Such specimens, because of the magnetic characteristics of the two phases, would be interesting subjects of study as magnetic materials. Hence the magnetic properties were considered in detail and are reported elsewhere.4 EXPERIMENTAL PROCEDURE The specimens of Fe-FeS eutectic were prepared from ultrapure iron (99.99+ pct) and high-purity sulfur (99.999+ pct). The iron was estimated to contain 60 ppm impurities (99.994 pct Fe) after zone purification.5 The ingots of iron were cut into chips, and the lumps of sulfur were ground into powder. In order to redice any nometallic impurities which might have accumulated during handling, the iron chips were annealed for 5 hr at 750° ± 10°C in a dry hydrogen atmosphere. Immediately after this treatment the chips were blended with the sulfur powder in eutectic proportions; the mixture was tamped into transparent fused quartz tubing and then vacuum-encapsulated under a pressure of 40 to 60µ of Hg. Because FeS expands upon solidification it was necessary to re-encapsulate the initial capsules so that oxidation reactions would be avoided when the inner tube cracked during solidification. For purposes of homogenizing the blended mixtures before solidification, the double capsules were heated to 750° ± 20°C and held for 20 hr; after this treatment the reacted product was weakly agglomerated. Each sample was then loaded into an apparatus for very rapid melting and freezing; this was accomplished by passing a molten zone through the specimen, using induction heating and a traverse mechanism. The resulting specimens solidified in the shape of the quartz tubing. Two sizes of specimens were used in this work, 18 mm diam by 100 mm long and 5 mm diam by 30 mm long. Metallographic examination of several ingots of both sizes after the above consolidation indicated no lack of compositional homogeneity and a random "as-cast" structure, because the travel rate was so rapid that unidirectional solidification was not achieved. Unidirectionally solidified specimens were resolidified in the apparatus shown schematically in Fig. 1, This equipment consisted of a kanthal resistance furnace mounted on the carriage of a zone-melting unit so that the heating element could traverse the length of the sample at a selected rate of speed. Large specimens were solidified with the mechanism tilted at ap-

Jan 1, 1967

By Robert Pike

THE first authentic description of an iron bath for the deposition of iron is probably that of Bottger in 1846, who used a bath containing ferrous sulfate and ammonium chloride. In 1861, Kramer deposited iron from ferrous chloride solution. Electrolytic iron was produced in 1.869 by Bietz, who used it for making some magnetic tests. In the same year, Klein is said to have worked out his process. Jacobi1 in 1869 described the results obtained in electroplating with iron on copper for making dies and plates for bank notes, by Klein's process. A letter from Klein to Jacobi describes the bath more fully. It consisted of FeSO4 + (NH4)2S04. Lenz2 described ?some properties of electrolytically precipitated iron. He used Klein's bath, FeSO4 + MgSO4 + MgCO3, to neutralize and obtained fine-grained and hard iron. His conclusions were as follows: 1. Electrolytic iron and copper contain gases, notably hydrogen. 2. The volume of gas absorbed by iron varies within wide limits, but it is easy for iron to take up very considerable quantities of gas. 3. The absorption of gas is principally in the first formed layers of iron. 4. When iron is heated, gas begins to come off below 100°, principally hydrogen. 5. Heated to redness, reduced iron oxidizes in water, in part at least at the expense of the oxygen of the water, decomposing it and setting free hydrogen, which is partly or wholly absorbed. Siemens,3 in 1889, was the first to propose a general process embodying a step for leaching a sulfide mineral with ferric chloride or sulfate and a step for regenerating the leach and depositing iron on a cathode in a diaphragm cell. So far as is known, Siemens did not carry out his patent

Jan 1, 1930

By W. H. Emmons

INTRODUCTION MINERAL deposits that have formed by the various geologic processes, when exposed to air and water at or near the surface of the earth, break down and form new compounds that are stable under surface conditions. Mechanical disintegration of the ores proceeds along with chemical alteration which generally is attended by oxidation, carbonation and hydration. Essentially all minerals are affected-silicates, carbonates, native metals, sulphides, etc. Where iron sulphides are present, oxidation yields sulphuric acid, and in the presence of oxygen and iron, ferric sulphate, a powerful solvent, is formed. Above the water level, in the vadose or shallow zone, both air and water are present. Below the water level air is excluded and that which is carried down with water is removed from the solution by reactions with reducing materials. Above the water level, solution is the pre-dominating process; below the water level, precipitation generally is equally important. In some deposits, particularly above the hater level, valueless materials are removed from the ore, leaving certain metals in a more highly concentrated state. This type of alteration, which has been termed negative enrichment, is common in ores of iron, aluminum, manganese and certain other metals. Some gold deposits, particularly those in which the environment is unfavorable for solution of gold, have been enriched near the surface by removal of material other than gold. Certain metals are readily dissolved in an oxidizing acid environment. These include copper, silver and, under certain conditions, gold. In the presence of iron sulphides, deposits of these metals are likely to be leached above the water level. The metals are carried downward to depths where air is excluded, and where they may be redeposited, generally below the water level. Such enrichment by addition of metals has been termed positive enrichment.

Jan 1, 1933

By B. A. Wilcox, A. H. Clauer

The tensile and creep deformation characteristics of fiber reinforced composites have been studied, primarily at room temperature. The matrix was an alloy of Mg-14 wt pct Li-1 wt pct Al (LA141A alloy) and the reinforcing fiber consisted of continuous wires of a high strength precipitation hardening stainless steel (AFC-77 alloy). The ultimate tensile strength and strength-to-density ratio of composites were much improved over that of the mmix, both at room ternperatwe and up to 200°C. Creep studies at room temperature revealed logarithmic weep behavior for wires and composites and steady state creep for the nonreinforced matrix. It was concluded that creep of the fibers controlled composite creep. The instantaneous logarithmic weep rate of the composite, 6, was related to the average tensile stress on the fibers, where n = 3.4. Mg-Li alloys are the lightest structural metals commercially available, e.g., the alloy LA141A (Mg-14 wt pct Li-1 wt pct Al) is 27 pct less dense than beryllium Although Mg-Li alloys have moderate tensile strengths at normal strain rates and ambient temperature, their creep strength is relatively poor, even at room temperature. Reinforcement by fibers offers a means of increasing the tensile strength as well as overcoming the limitations of low creep strength. With a proper choice of reinforcing filament, composites could be designed with higher strength-to-density and modulus-to-density ratios than the matrix alloy. This communication reports a study on the tensile and creep characteristics of alloy LA141A reinforced with continuous wires of a high-strength precipitation hardening stainless steel (AFC-77 alloy). The matrix has a bcc structure, with possible precipitates of AlLi and MgLi2A1,3 and is ductile at room temperature Stainless steel wire was chosen as the -reinforcing filament since previous work at Battelle4 showed that a good bond between wire and matrix could be produced in this system. For all volume fractions of reinforcing wire, the theoretical composite strength-to-density ratio is greater than that of the matrix and the modulus-to-density ratio is somewhat lower than that of the matrix. EXPERIMENTAL PROCEDURES The 0.004-in. diam AFC-77 wire was obtained from two suppliers: National-Standard Co.* and Crucible 0.13 Si, 0.18 V, 0.011 P, 0.012 S, balance Fe. In the as-received condition, wires from both sources had room-temperature ultimate tensile strengths of 585,000 to 590,000 psi with approximately 2 pct total elongation and 40 pct reduction in area. Composite preparation was accomplished by the vacuum infiltration technique. This involved placing the continuous wires in a mild steel tube (1/8-in. ID), capping one end of the tube with a sheet of the matrix alloy, and evacuating the other end of the tube. When the capped end was placed in a crucible of the molten matrix alloy and held for 31/2 min at 70O°C, the liquid metal was drawn up the tube approximately 7 to 8 in. A cross-sectional view of a typical composite is shown in Fig. 1. This preparation technique promoted excellent bonding between the matrix and wires, and porosity was rarely observed. Test specimens for both creep and tension studies were prepared by machining off the steel tube. Tensile tests on the wires and composite specimens were made in an Instron using a cross-head speed of 0.01 in. per min. The composite specimens had no reduced section and were held in self-tightening grooved serrated grips. Most of the specimens broke in the effective 1-in. gage section. Even though several tests fractured in the grip section, their ultimate strengths were essentially the same as those of specimens which fractured in the gage section. Creep specimens of the composite were gripped in a similar manner, and

Jan 1, 1970

By J. J. Luchessa

HAULAGE was one of the many problems to be solved in the successful handling of the Miami Copper Company's low-grade orebody. The ore extracted had to be increased from 1000 to 18,000 tons per 24 hours over the existing track-age and haulage way. This called for increased speed, longer trains, in¬creased car capacity, and a block signal system so as to maintain a fixed schedule and headway. The motive power in service at the time of this transition consisted of Baldwin-Westinghouse 6-ton trolley locomotives. (See Fig. 3.) These locomotives were purchased to handle twenty inverted-V-bottom side-dump cars of 60 cu. ft. capacity. Dimensions were limited as to height on account of ore chutes, width on account of short radius curves, and length of 12 ft. from bumper to bumper- so that the locomotives could be handled on the man and material hoist which has a cage length of 121/ ft. The limited length made it possible to bring the locomotives to the surface for periodic overhauling and major repairs such as changing wheel tires, gears, and

Jan 1, 1934

By J. P. Newell, R. W Storey

This paper describes the development of a continuous float-and-sink process to produce coal low enough in ash content to be suitable for production of electrodes. The cleaned coal had a combined iron and silicon content of 0.239 pct. The efficiency of recovery was 84 pct. AUGER mining is a form of continuous mining in that it completely replaces with a one-cycle operation the older conventional cut, drill, shoot, and load method of mining. Relatively new, having been utilized only within the last few years, it is even more continuous in its production of coal than some other forms of continuous mining being practiced in this country today. There are at present coal recovery augers in operation working along strip-mined highwalls from the outside. This paper will deal with underground mining, specifically with an experiment which was carried out with a machine developed for this purpose. The location of this experiment was in Pike County in eastern Kentucky in the upper split of the No. 3 Elkhorn seam. Coal height was 32 in. and roof conditions were very bad, with 10 in. of soft draw slate coming down with every cut in conventional mining. The coal is high-grade bituminous, excellent for metallurgical coking. Underground auger mining fills a need for a method of recovering coal in thin seams, under bad roof conditions or in split seams. In many cases it might save money by eliminating the handling of excessive quantities of rock. In fact, if the coal can be recovered, as in the case of this experiment, without mixing with any impurities outside the seam, it may be possible to load or ship a satisfactory product with little or no preparation or cleaning expense. The need for some economical method for recovering coal from thin seams is becoming more pressing as the more profitably mined seams are exhausted. Basic Principles of Auger Mining The principles of the auger, or screw conveyor, have long been used in drilling small diameter holes for blasting and other purposes. These same fundamentals apply to large diameter drilling. However, considerably more attention was given to designing a cutting head that would not pulverize the coal and consequently would require a minimum of power to drive it. The head, as designed for this job, consists of a cylinder 25 in. in diam with steel bits set in 3 positions spaced around the forward rim. A conventional coal drill bit, at the head of a bursting cone in the center of the cylinder, trails the forward rim slightly, see Fig. 1. The bursting cone and auger connections are anchored to the cutter barrel by 3 arms spaced at 120". This head design proved to be very satis-

Jan 1, 1953

By J. P. Newell, R. W. Storey

This paper describes the development of a continuous float-and-sink process to produce coal low enough in ash content to be suitable for production of electrodes. The cleaned coal had a combined iron and silicon content of 0.239 pct. The efficiency of recovery was 84 pct. AUGER mining is a form of continuous mining in that it completely replaces with a one-cycle operation the older conventional cut, drill, shoot, and load method of mining. Relatively new, having been utilized only within the last few years, it is even more continuous in its production of coal than some other forms of continuous mining being practiced in this country today. There are at present coal recovery augers in operation working along strip-mined highwalls from the outside. This paper will deal with underground mining, specifically with an experiment which was carried out with a machine developed for this purpose. The location of this experiment was in Pike County in eastern Kentucky in the upper split of the No. 3 Elkhorn seam. Coal height was 32 in. and roof conditions were very bad, with 10 in. of soft draw slate coming down with every cut in conventional mining. The coal is high-grade bituminous, excellent for metallurgical coking. Underground auger mining fills a need for a method of recovering coal in thin seams, under bad roof conditions or in split seams. In many cases it might save money by eliminating the handling of excessive quantities of rock. In fact, if the coal can be recovered, as in the case of this experiment, without mixing with any impurities outside the seam, it may be possible to load or ship a satisfactory product with little or no preparation or cleaning expense. The need for some economical method for recovering coal from thin seams is becoming more pressing as the more profitably mined seams are exhausted. Basic Principles of Auger Mining The principles of the auger, or screw conveyor, have long been used in drilling small diameter holes for blasting and other purposes. These same fundamentals apply to large diameter drilling. However, considerably more attention was given to designing a cutting head that would not pulverize the coal and consequently would require a minimum of power to drive it. The head, as designed for this job, consists of a cylinder 25 in. in diam with steel bits set in 3 positions spaced around the forward rim. A conventional coal drill bit, at the head of a bursting cone in the center of the cylinder, trails the forward rim slightly, see Fig. 1. The bursting cone and auger connections are anchored to the cutter barrel by 3 arms spaced at 120". This head design proved to be very satis-

Jan 1, 1953

By L. E. Young

The progress of mineral industry education will be limited to the period prior to World War II and will be considered as primarily a division of engineering education. Its relation to progress in the mineral industry and to the activities of the American Institute of Mining and Metallurgical Engineers will be emphasized. The history of mineral industry education has been recorded most completely and authoritatively by Dr. T. T. Read in his recent volume in the Seeley W. Mudd Series of American Institute of Mining and Metallurgical Engineers publications, entitled, The Development of Mineral Industry Education in the United States. Therefore, most of the historical details will be omitted from the discussion and an effort will be made to point out significant developments and to analyze trends. Introductory Statement and Significant Points in Progress Among the significant points in the development of mineral industry education in the United States since 1871, the following deserve particular mention: 1. The number of institutions offering undergraduate instruction has increased, particularly during the years 1890 to 1925; the number of students enrolled in undergraduate study has increased greatly, largely on account of the development of courses in petroleum engineering and increasing interest in metallurgy. 2. The selection of students to be admitted to undergraduate courses has been improved through the advisement, counseling, and guidance programs sponsored by the Engineers' Council for Professional Development. 3. Improved instruction methods all the training of the teaching staff have been promoted by the educational institutions themselves, but with the most effective stimulus and guidance of the American Society for Engineering Education and the Engineers' Council for Professional Development. 4. The accrediting of undergraduate curricula through the Engineers' Council for Professional Development, consitlering both qualitative and quantitative criteria, has done much to improve standards of instruction in engineering education for thc mineral industry. 5. Undergraduate curricula and courses are revised currently to meet the needs of the American mineral industry. New curricula are developed currently to permit specialization in technical fields, particularly in the fourth year of undergraduate work. 6. There has been a strengthening of the fundamental courses in mathematics, physics, mechanics, and chemistry, and at the same time these courses are being adapted to the most recent developments in the industry, including metallurgy, geophysics. petroleum engineering, petroleum technology, ceramics and SO forth. 7' There has been continuing improvement in plant and laboratory facilities of the educational institutions.

Jan 1, 1949

By John B. Miles

The present period of depression in the iron industry, with the resultant close approximation of the cost of production to the selling-price of pig-iron, should make the discussion of this subject at this time not only interesting but profitable. It is possible that it may result in the collection of data, which when added to those set forth in this paper will clearly indicate the influence of the rate of driving a blast-furnace upon its fuel-economy. The question is not whether an excessive rate of driving (meaning a rate definitely in excess of the average rate in the United States) results in an increase in the fuel-consumption, but rather whether a rate considerably less than the average does not result in a marked decrease in the fuel-consumption. The commercial and metallurgical sides of this problem must be kept separate. With a large margin between the cost of production and the selling-price of pig-iron, and a plant already in operation, it is frequently profitable to sacrifice a couple of hundred pounds of fuel per ton of pig-iron in order to secure the greater gross profits resulting from a larger tonnage. When this margin decreases with a plant in operation, or when the determination of the size of a new furnace intended for a certain production confronts the management, a clear understanding of the effect of the rate of driving upon fuel-economy becomes necessary. If it be granted that slow driving leads to low fuel-consumption, it should be borne in mind in the design of a new plant for the production of a certain tonnage that the adoption of an economical rate of driving increases only the size of the furnace proper, whereas, due to the decrease in quantity of blast required on account of the decrease in fuel burned, the stoves, the blowing-engines, the boilers and the piping may be de-

Jan 1, 1909

By C. H. Keplinger

WARTIME factors have strengthened the production engineering consciousness of the petroleum industry. The basic principles of sound oil-production technology have been accepted as the standard by the industry and the governmental co-ordinating agencies. Every effort is being made to furnish larger quantities of petroleum with a minimum expenditure of materials and under strict conservation practices. The sphere of influence of production engineering extends from fundamental reservoir control of withdrawal rates and reservoir pressures to bolstering production from stripper wells. Serious transportation difficulties in moving oil to the East Coast have stimulated secondary recovery operations in the Appalachian and East Central oil-producing states. Diminishing discovery of new oil reserves by exploration activities increases the importance of promoting efficient oil-producing methods and practices throughout all productive areas in the United Nations.

Jan 1, 1943

By K. E. Brown, F. W. Jessen

It is deemed feasible to store atomic reactor fuel wastes in salt dome cavities when the differential pressure acting on the cavity does not exceed 3,000 psi and the temperature is less than 400°F. Tests at pressure increments of 1,000 psi were conducted on a 2-in, cylindrical cavity contained in a 6-in. long X 6-in. diameter salt core. The cavity exhibited stability under pressures up to 3,000 psi and temperatures to 300°F. At temperature ranges of 100 to 400°F and with pressures of 5,000 psi and above continuous deformation of the cavity resulted. Initial movement of the salt was observed at all pressares. This was evidenced by vertical deformation and cavity size reduction. INTRODUCTION The development of storage techniques for safe disposal of atomic reactor fuel wastes is a goal of the Atomic Energy Commission. Salt domes have been used successfully for storage of liquefied petroleum gases and hence should prove to be suitable for liquid waste products of atomic reactors. The purpose of the following work is to evaluate the practicability of utilizing salt dome cavities for such wastes and to de-termine particularly the effect of pressure and temperature on a salt cavity. This work represents a part of a comprehensive study covering the over-all problem of storing re- actor fuel wastes in salt domes and/ or salt beds. The problem of accurately determining the stresses which exist in rocks in the earth's crust is indeed a complex one. Theoretical studies have differed widely in many of the basic assumptions about the physical properties of the rock itself. Some solutions of problems in underground stress analysis assume that rock is elastic, homogeneous and isotropic in character; others assume that rock possesses plastic, viscous, elasticovis-cous properties, or a combination thereof. Experimental evidence has shown that salt possesses plastic, viscous and elasticoviscous properties.' Recent work has shown that salt becomes more plastic with temperature.' APPARATUS AND PROCEDURE For experimental study a cylindrical cavity was chosen for analysis since it provided maximum volume per unit of depth with constant diameter. This particular cavity shape, allowing for irregularities, can be easily leached out of salt domes in field operations. For the purpose of approaching underground storage conditions as nearly as possible, the following factors were considered: (1) control of pressure and temperatures, (2) measurements of temperature gradients throughout salt mass, and (3) measurement of structural stability of salt cavities. In order to obtain triaxial pressure on the salt cavity without resorting to the application of fluid pressure directly on the salt mass, a system was designed whereby the same effect could be produced through axial loading only. By cutting a core to close dimensions to fit a steel test cylinder and applying axial pressure, a lateral pressure was obtained. This equipment is shown in Figs 1 and 2. A steel cylinder was made from

By B. C. Craft

Development and exploratory work in Mississippi during 1934 was rather active, resulting in the expansion of the proven area and the drilling of a number of important wildcat wells. Mississippi showed a decrease in drilling operations during 1934. There were 36 completions from 18 counties during this period compared with 58 completions from 22 counties during 1933. There was a considerable decrease in activity in the Jackson gas field in Hinds and Rankin counties with only 9 completions, resulting in 8 gas wells and 1 dry hole compared with 17 gas wells, 2 oil wells and 7 dry holes during 1933. Leasing and geophysical work was reported from several sections of Mississippi last year. Extensive exploration and drilling were carried on in Lamar, Hancock, Pearl River, Greene and Stone counties and on the flanks of the Jackson anticline. Exploration will be continued in these areas during 1935. Four important wildcats were completed during 1934, all of which were reported as being structurally high, but without having important shows of oil or gas. These tests were: Hix and Germany's, J. J. Newman Lumber Co. No. 1, sec. 21-4N.-15W., Lamar County, abandoned at 3520 it. in the Wilcox; United Gas Public Service Company's Davis No. 1, sec. 30-1N.-5W., Greene County, abandoned at 7439 ft.; Gulf Refining Company's May L. Williams No. 1, sec. 33-5S.-17W., Pearl River County, abandoned at 4800 ft.; and Clarke County Oil Company's S. B. Kirkland No. 1, sec. 10-2 N.-16E., abandoned at 4002 ft. in the Eutaw. Another interesting wildcat was Gulf Refining Company's Dantzler Lumber Co. No. 6, sec. 22-4S.-llW., Stone County, abandoned at 7700 ft. (according to reports below the Selma chalk). A total of 114 of the 132 gas wells completed in the Jackson gas field are still producing and have a combined open-flow capacity of 4,145,-696,000 cu. ft. Four of the abandoned gas producers were never connected to the lines. The open-flow capacity of three wells in the Amory field is approximately 1,000,000 cu. ft. Producing against a line pressure of 50 lb., the demand during December greatly exceeded the capacity.

Jan 1, 1935

By Samuel G. Lasky

FAULTING at Kennecott, with its attendant fracturing, is unusual, complex, and important. As study and knowledge of the various fault systems have progressed, appreciation of that importance has helped in the selection of proper horizons for exploration and in the avoidance of useless crosscutting and drifting. During the study of this faulting and fracturing, a suggestion concerning the formation of the ore-bearing fissures occurred to me. Further study in the available portions of the approximately 45 miles of workings in the Kennecott mines for the purpose of checking up the the suggestion led to the hypothesis which this paper will attempt to present. Briefly, the hypothesis may be stated as follows: The formation of transverse faults that stop against a main system is connected with changes in the strike or dip of the main fault, and such cross faults or fractures lie in the moving block of the main fault system and indicate a change in strike or dip of the main fault. It has been found that each kind of change tends to produce definite effects and that careful study of the evidence can often suggest the exact type of change. Outline of Kennecott Mines Geology The mines at Kennecott are on the northeast flank of a broad anticlinell where erosion has exposed the Upper Triassic Chitistone limestone resting conformably on the Permian or Triassic Nikolai greenstone.2 These two are the only formations exposed in the immediate vicinity of the mines that bear relation to the ore deposits. The Nikolai greenstone is a series of altered basaltic lava flows, the actual thickness of which is unknown. The Chitistone limestone is the ore-bearing formation. At its base is a bed of about 5 ft. of red, green, or black shale which shows strong evidence of movement wherever it is exposed underground—one of the

Jan 1, 1929

By F. C. Clapp

Although many oil fields have been, and still are being, discovered in Oklahoma, the geology and structure of most of them have not become familiar to the general public because of the delay in securing government geological surveys and the reluctance of oil companies and other intercsted parties to give out their "inside information " Therefore, until official surveys are available, it behooves us to publish geological results as soon as possible. Fortunately the writer has been authorized by the Cement Field Oil Co. to publish his data on the Cement field, Caddo County, at this time. Locality and Description The Cement field is situated in the part of Oklahoma known generally until recently, as "Healdton fields," and lies 60 mi. (96 km.) northwest of the Healdton field proper. Like the Healdton field, it forms an approximate ellipse, trending northwest and southeast through the village of Cement on the St. LouisSan Francisco Railroad, on which it is reached in 21/2 hours from Oklahoma City. In its geological structure, the field constitutes an anticline over 13 mi. (21 km.) long and from 1 to 3 mi. wide; the point of greatest width being not far from its intersection by the above-named railroad. The major axis trends north 75' west from the village of Cement; but eastward appears deflected (if field interpretations are correct) to about south 45" east. About 5 mi. south lies an approximately parall el syncline, which may be conveniently called the Cyril syncline, the south and west boundaries of which may be distant many miles, but forming a closed basin south of the Cement anticfine. The positjon of the offsetting synclinal axis, which is believed to lie north and east of-Cement, has not been discovered. TOPOGKAFHY In the southwest part of the state, nearly all maps of Oklahoma show two mountain areas—Arbuckle and Wichita—which are conspicuous geological and topographic landmarks. In addition, some maps show a third, and smaller, range, named the Keechi Hills, in the vicinity of Cement. These hills also form a conspicuous feature in the landscape; but for some reason they have been neglected by geologists, and the

Jan 1, 1921

By Edward Keller

In order to conduct intelligently the sampling of copper of various forms and grades, solid or in molten furnace-charges, a knowledge of this subject is essential. Yet figures and tests have been persistently withheld from publication, and the books at our command give us little or no information in this regard. This gap in our copper-literature has led to a series of experiments, the results of which are given below. Nearly all gold- and silver-bearing copper, destined for shipment, is cast into the form of bars or pigs. For the sampler, the question arises, Does copper, so cast, remain homogeneous ? If it does, sampling should present no difficulties; but, from experience, we know that this is not the case, and we are thus led to study the behavior of the precious metals arid impurities in copper when the latter changes from the molten to the solid state. For the purpose of the experiments here described, all available grades of copper were selected, and all of them mere subjected to the same conditions, an important requisite for proper comparison. The molten copper obtained directly from reverberatory- and blast-furnaces was cast in a cast-iron mould, the sides and bottom of which were 1 inch thick, and would, therefore, give the copper a fair length of time to chill. The inside dimensions of the mould, and, consequently, of the block of copper obtained, were: length, 10 inches; width, 9 inches; and depth, 5 inches. Fig. 1 illustrates the method employed to obtain samples from these blocks. A was cut away, and the face so produced BALTIMORE COPPER WORKS,

Jan 1, 1898