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By K. A. Johnson, F. H. Ellinger, C. C. Land

The Pu-La alloy systenz has been studied by thertnal, tnzcrographic, and X-ray diffraction methods. It is churacterized by a liquid miscibility gap, a maximum solubility of about 20 ut. pct PM in y lanthunum and 19 at. pct PI* in 0 lanthanum, very little soluibility of lanthanum in the plulonium allotropes, and the absence of intermediate phases. THE existence of immiscible liquids in the Pu-La system has been reported by Schonfeld.1 A tentative phase diagram based on the results of thermal-analysis experiments has been constructed by Poole et a1 2 This diagram shows a liquid immiscibility loop with a monotectic at 77 at. pct La and 846°C. 7 lanthanum is shown to dissolve 20 at. pct Pu and to decompose by an inverse peritectic reaction (y La = L , + p La) at about 82 at, pct La and 833°C. The ß lanthanum solvus was not determined, but the thermal work indicated a maximum solubility of 16 at. pct Pu in ß lanthanum. The present investigation has defined the solubility limits of plutonium in y lanthanum and 0 lanthanum, and, with the exception of minor discrepancies, has verified the results of Poole et al. 1) EXPERIMENTAL The electrolytic plutonium melting stocks were better than 99.9 wt pct pure, the main impurities being 90 ppm Fe and 50 ppm W. The lanthanum melting stocks, supplied by Research Chemicals and the Cerium Metals Corp., were about 99 wt pct pure, the main impurity detected by our spectrochemical analysis being 2000 ppm Fe. The components for each alloy button (-5 g) were weighed on an analytical balance and were melted together in a conventional arc furnace. If no significant weight loss occurred during melting, the as-weighed

Jan 1, 1968

By E. E. Donath, W. L. Crentz, D. Doherty

Maurice Rey—The influence of cyclone diameter upon the fineness of separation is an important point which, however, cannot be discussed adequately if the injection pressure or the rate of flow are not specified. Perhaps some light can be thrown on the matter by using the formulas derived by Dahlstrom. Let us consider several geometrically similar cyclones where the apertures e and b are equal and proportional to the diameter D and which are operated with the same pressure drop. Eq 8 of Dahlstrom's paper can be written: Q Q = K D'. " or. if F is constant: Q = K D18 K is a constant of proportionality. Introducing this value of Q in eq 13 gives elimination efficiency = K D0' " Elimination efficiency, in the terminology of Dahlstrom, means the diameter of particles, in microns, which divide equally between the underflow and the overflow. This denomination is regrettable and it would be preferable to call it diameter of separation or characteristic size or any other name connoting a size rather than an efficiency. Whatever the name used, the above equation shows a slow increase in the fineness of separation when the diameter of the cyclone decreases. For example, if a 14-in. cyclone gives a 400-mesh separation (37 microns), geometrically similar cyclones, having the same pressure drop will give separations at the sizes shown below.

Jan 1, 1951

By D. S. Eppelsheimer, D. N. Williams

The cold rolled textures of iodide titanium and of three samples of commercial titanium were examined using the Schulz-Decker Geiger counter technique. The iodide titanium and two of the three samples of commercial titanium showed a (0001) [1010] texture rotated 30' toward the transverse direction about an axis in the rolling direction. The third sample of commercial titanium showed a double texture. THE metals of the hexagonal system tend to deform similarly if the c/a ratios are similar. Thus titanium, zirconium, and beryllium, with c/a ratios of 1.601, 1.590, and 1.570, respectively,l should have similar cold rolled textures. The cold rolled texture of high purity iodide titanium has been described as (0001) [1010] rotated 30" toward the transverse direction about an axis in the rolling direction.' The texture of zirconium has also been reported as (0001) [1010] with a transverse rotation from the ideal position of approximately 30" about an axis in the rolling direction." This texture differs from that reported for titanium however since a continuous spread of (0001) poles toward the transverse direction was reported rather than distinct (0001) maxima 30" from the rolling plane normal. Beryllium has a texture similar to that of zirconium although the angle of transverse rotation of the (0001) poles is much less.' These three metals thus show a common type of cold rolled texture, as yet unexplained, which can be described as (0001) [1010] with various degrees of rotation toward the transverse direction about an axis in the rolling direction. Since titanium showed the greatest degree of rotation from the (0001) [1010] position, the cold rolled texture of titanium was re-examined using a semiquantitative Geiger counter X-ray technique to obtain more accurate experimental data from which a theoretical interpretation of this new type of hex- agonal rolling texture could be developed. The cold rolled textures of iodide titanium and of three samples of commercial titanium were determined. Table 1 gives the analyses of the titanium samples. Experimental Procedure Preparation of Samples: Prior to the final rolling operation each of the samples was given an initial reduction of approximately 50 pct and annealed to remove the gross effects of any previous treatments. Samples were annealed in vacuum, high purity helium, and air to determine whether annealing atmosphere had any effect on the cold rolled textures developed. All samples were annealed 1 hr at 800°C. Grain size determinations were made using the formula, 1.075 in which n is the number of grains counted in an area A (in sq mm) and M is the magnification of the area counted.' This formula gives the diameter between opposite flats assuming hexagonal grains. At least three areas containing more than sixty grains each were counted in each grain size determination. Rockwell B hardness readings were made on the annealed samples. The results of the measurements of

Jan 1, 1954

By A. L. Mular. Discussion by G. A. Parks

G. A. Parks (Associate Professor, Dept. of Mineral Engineering, Stanford Univ., Stanford, Calif.) - Professor A. L. Mular in his paper Effect of Impurities on the Flotation Behavior of Zinc Oxide (T.P. 65B206) has made a most interesting and thought provoking contribution. In view of his recognized lack of measurements of the ZPC's of the doped samples and lack of direct evidence for participation of semi-conducting electrons in collector adsorption an alternate explanation should be considered. The alternate also

Jan 1, 1967

By Allen H. Rogers

It has always seemed to me that there is a certain similarity between the work of the mining engineer and that of the doctor of medicine — each has very often to be governed in his actions by conditions which he cannot see. It is not necessary to detail the unseen conditions with which the mining engineer or geologist has to deal—the further extension of ore-bodies, the existence of new ones, the throw of a fault, the probable change in grade' or character of the ore with advance of the workings, are a few of the conditions which the mining engineer has to determine as well as he can from the deductions he is able to make from what he can observe. Just so the physician is often confronted with conditions that he can not observe. Probably less than half of human ills make a manifestation at the surface of the body from which definite and certain conclusions can be drawn. The diagnostician must observe various things and, from these observations in combination, conclude what his course should he to bring about the cure of the trouble. Both professions would be assisted immensely by any agency that would permit them to look below the surface, something that would make more certain the diagnosis which each is called upon to make. The physician has had such an agency since 1895, when Röntgen discovered the X-ray; which, by making possible shadowgraphs of the osseous portion of the human body, advanced immensely the diagnosis of bone lesions Later, with improvement in the technique and more understanding in the interpretation of what the photographic plate shows, other portions of the human anatomy could be examined and at the present time there is hardly an instance of internal disorder to which the aid of the X-ray is not called. Some organs are made opaque by administering mineral substances; in other cases, conclusions are drawn from barely perceptible shadows on the photographic plate. Generally the surgeon's knife is directcd with exactitude to the seat of the trouble and so not only is the difficulty revealed but the necessity for an exploratory operation is averted. What the X-ray is to medicine and surgery, geophysical prospecting methods are to the mineral industry. They give the mining engineer and geologist information regarding subsurface conditions which otherwise

Jan 1, 1929

The authors have done a very thorough job in analyzing the factors affecting turndown sulfur performance at Inland's No. 4 B.O.F. While many of the results are not unexpected, it is helpful I am sure to have quantified many of the relationships that the operators rely upon daily. On the other hand, however, the results shown for ladle skimming are very surprising. I do not doubt the statistical relationship shown but I feel, based on our experience at Youngstown, that some other parameter has been ignored in the data on ladle skimming. It was our experience that by skimming our hot metal transfer ladle we could reduce our lime consumption by eleven percent while obtaining sulfur removal comparable to that shown by the authors. I would like the authors comment of similar adjustments on the lime charge that were made on skimmed heats at Inland. If not, it would seem that one could gain more desulfurization in the B.O.F. by raising the hot metal manganese than by installing a skimmer. The author's state that no comparisons are valid between the data sets for the two time periods involved because of the difference in the consumption of No. 2 Bundles. I feel this in fact is one of the important conclusions to be drawn from the paper, as there seems to be approximately a 10-20 percent difference in percent of heats that are under 0.020 percent sulfur for similar conditions, which is an extremely important difference with today's demands for low sulfur. I would like the author's comments on the difference in the amount of 82 bundles consumed. Along this same line I was quite surprised by the relatively low number of heats that had a first turn down of 0.020 percent sulfur or less. Also rather disconcerting are the conditions necessary to achieve a first turn of 0.020 percent sulfur, 50 - 60 percent of the time, as required by today's specifications. It is a problem which we are well aware of, but the numbers are still shocking.

Jan 1, 1972

ASIDE from the John Fritz Medal, in which the Institute partici¬pates through its representation on the John Fritz Medal Board, the Institute itself has three major awards to make annually and one special prize for excellence in technical papers, as follows The Robert W. Hunt Medal and Prize, The J. E. Johnson, Jr , Award, the James Douglas Medal, and The Lewisohn Platinum Prize to senior members. ROBERT W. HUNT MEDAL AND PRIZE The partners of Robert W. Hunt established a fund which was presented to the Institute at a fitting ceremony on May 27, 1920, to establish an annual medal and a sum of money to be awarded under the following rules¬ 1 The award shall consist of two prizes, first of a gold medal, second of a sum of money, a certificate to accompany each prize. The money prize shall not be awarded to -a member over 40 years of age, but under unusual circumstances, both prizes may be allotted to one person provided that he is not over 40 years of age. In general it will be understood that the Committee shall award the money prize to the younger men, rather than the medal 2 The awards shall be made not oftener than once a year to that person or persons contributing to the Institute the best original paper or papers on iron and steel The scope of the term "iron and steel" shall be determined by the sub-committee considering the awards In general, papers dealing with the practical side of the subject have preference over those dealing with the theoretical side m recognition of the fact that Captain Hunt's main contributions to the industry have been in the improvement of production and quality of material. 3 A sub-committee of three to five, including the Chairman of the Iron and Steel Committee, shall be appointed by the Iron and Steel Committee annually to adjudge the award subject to approval.. , 4 The awarding committee shall submit its report to the Iron and Steel Committee at its October Meeting, and the award be certified to the Secretary of the Institute in time to permit the presentation to be made at the Annual Meeting of the Institute. 5 The recipient of the award shall be designated "The Hunt Medallist " This prize is administered by the Iron and Steel Committee.

Jan 1, 1923

By J. Chipman, H. R. Larson

The data previously reported for the quantity as a function of oxygen pressure at 1550°C have been used to compute the activities of Fe, FeO, Fe2O3, and COO in slags of the ternary system. Activities of the first three have been obtained also for two quasi-ternaries involving fixed CaO:SiO2 ratios. IN a previous paper1' the authors reported the results of an investigation into the effects of oxygen pressure on the composition of various simple slags analogous to some of those which are found in steel-making practice. The ratio of ferric iron to total iron was studied at 1550°C in iron oxide melts to which lime, magnesia, lime-plus-silica, and other oxides were added. The oxygen pressures involved those of air, carbon dioxide, and carbon dioxide plus carbon monoxide in several proportions. Although very low oxygen pressures could not be used, the slag-metal equilibrium studies of Fetters and Chip-man' permitted extending the results to slags in equilibrium with iron. For the ternary system CaO-FeO-Fe,O, the oxygen pressure-composition relationship has been determined from zero percent lime to lime saturation over an oxygen pressure range from air to that represented by equilibrium with liquid iron. Lime and silica were added to iron oxide in the ratios 0.54, 1.306, and 2.235 to form three quasi-ternary systems which were also studied over the entire region of liquid melts at 1550°C. Ternary Gibbs-Duhem Equation Wagner" has developed a method by which the activities of two components of a ternary system can be calculated if' the activity of the third component is known throughout the composition range being considered. The fundamental form of the Gibbs-Duhem equation for ternary systems is N, d In a, + N2 d In a, + N3 d In a3 — 0. Wagner has developed a usable form of this equation by introducing the term y = N3/(N3 + N1) and rearranging the equation to give (? In a1/?N2)x = -y/(1-N2)2 (? In a2/?y) x2 N2/1-N2 (? In a2/?N2) y To apply this equation to the slag system CaO-FeO-Fe,O,, the activity of one of these components must be known. However, the only activity which is known from the experimental data is the activity or pressure of oxygen in the gas phase with which the slag is in equilibrium. The activity of oxygen in the slag can be defined as the square root of the oxygen pressure. In order to use oxygen as one component, the composition of the slags must be converted to the basis Fe-O-CaO. Oxygen, exclu-sive of that contained in CaO, then becomes com-ponent 2 in Eq. 1, Fe is selected as 1 and CaO as 3. Then y = Ncao/(Ncao + NFe). Eq. 1 then becomes (? In a fe/? Nx) y = -y/(1-No)2 (? In ao/?y) xp - No/ 1- No (? In ao/ O No) y. In order to evaluate Eq. 2, the boundary conditions must be known. The obvious choice of a standard state for iron is to assign slags in equilibrium with iron an activity of one. Then In a,., or log aFe, which is substituted for convenience, is determined by integrating along a line of constant y from the slag in equilibrium with iron to the composition at which log a,, is to be determined. Mathematically this can be expressed as log aFe (Nlog y) = log a'Fe + (? log a Fe/? No) dNo where the primes indicate equilibrium with liquid iron and a'Fe = 1. When Eq. 3 is integrated along a line of constant y, the following is obtained: log a Fe (No, y) = - y No ?/ No ? y ( log ao/(1- No)2) No d No - No/1-No d log ao. Lime-Iron Oxide Slags Iron Activity: The oxygen pressure of lime-iron oxide slags is shown in Fig. 1 as a function of j, de-fined as j = Fe+++/(Fe++ + Fe +++) for various constant mol percentages of lime. The j values at 0 to 60 pct lime were then determined for oxygen pressures of 1, 10-1, etc. to 10-" atm. For purposes of calculation, the line for zero percent lime was extrapolated to

Jan 1, 1955

By I. Cornet

With the greatly expanding use of magnesium during the war, it appeared necessary to the War Metallurgy Committee that the notch sensitivity of magnesium alloy extrusions be further investigated and the influence of various factors upon notch sensitivity be noted. Accordingly, the National Defense Research Committee of the Office of Scientific Research and Development placed a research contract with the University of California, supervised by the War Metallurgy Committee. The work discussed herein was done under "Restricted" Project NRC-21, reported in Dec. 1943~; it has been released for publica-tion by the O.S.R.D. Scope of the Investigation The notch sensitivity of various magnesium alloy extrusions was determined under axial tension, and also under several conditions of nonaxial tension. Hardness, grain size and other metallographic features were observed; stress-strain data were obtained, and the chemical compositions of the alloys were determined, in order to correlate these quantities with thc notch sensitivity. Notch sensitivity under axial tensile load was determined for a few specimens which had been cold worked to various degrees by tensile prestraining. Magnesium alloy extrusions studied included Dowmetal 0, X, J, and A(. For comparison, extrusions of aluminum alloy 24s-T, cast bars of aluminum alloy 122-T2, and cast bars of magnesium alloy C were also tested. The specified chemical composition of these alloys is given in Table I. All bars tested were within specification limits of composition. Investigation of thc tensile notch sensitivity of various magnesium alloy extrusions, under conditions of axial and eccentric load, showed little or no correlation with stress-strain or other conventional data. Since the many uncontrolled variables present might mask significant relationships, one alloy was selected for intensive study. Magnesium 0 alloy extrusions were subjected to experimental heat treatments, and the ,Changing hardness, tensile strength, microstructure, and notch sensitivity observed. Experimental Techniques and Procedures Tensile Testing Bars used for axial loading were machined with % in.- and with 34-in. minimum diam1 and included specimens with 60" V notches (Fig I and 2). Each V-notched specimen was roughed out carefully and then finished with a honed tool. These Y-notched bars were sampled frequently, sectioned, polished, and examined at 500 X magnification to control

Jan 1, 1949

By I. W. Farmer

Case histories are introduced to illustrate how an understanding of the mechanics of deformation of mine structures associated with longwall layouts can be used to improve stability. Particular examples include: (a) deformations associated with longwall caving, (b) the effect of support pressure on roof deformation above a longwall face, (c) the effect of pack design on longwall access road closure, (d) the effect of rock deformation characteristics on floor heave.

Jan 1, 1982

By Robert B. Sosman

The relative temperature distribution within a coke oven and among the ovens in a battery can be obtained automatically for the operator's guidance by sighting a total-radiation pyrometer on the face of the coke as it is pushed out, and recording the surface temperature. Keeping the instrument clean and keeping its view of the coke unobstructed by smoke and dust are the principal problems. Typical records from three plants are presented in this paper, showing that the temperature patterns are reproducible. Development OF Method The method of coke pyrometry described in this paper was introduced in 1936 by E. A. Lee, then Assistant Superintendent, now Superintendent, of the Coke Plant at Lorain Works, National Tube Co., Lorain, Ohio. At the request of the Coke Committee of the United States Steel Corporation, the Research Laboratory of the Corporation undertook to adapt the method to the somewhat different conditions met with at the Gary Works of the Carnegie-Illinois Steel Corporation, Gary, Ind., and at the Clairton Works of the same Corporation at Clairton, Pa. This work was done in cooperation with the Leeds and Northrup Co. of Philadelphia and later with the Brown Instrument Co. Division of Minneapolis-Honeywell Regulator Co., Philadelphia. We of the Research Laboratory wish to express our appreci- ation of the courtesies extended by Mr. Lee, by A. N. Cole, Superintendent of the Gary coke plant, and by D. P. Finney, Assistant General Superintendent in charge of coke-plant operations at Clairton. We are also indebted to the instrument companies for the loan of a part of the equipment. At Gary and Clairton the instruments were installed and various experiments were made by J. W. Bain, of the Research Laboratory of the United States Steel Corporation. Pyrometry of Coke The coke inside a by-product oven is almost completely inaccessible to pyro-metric instruments. The temperature in the walls can conceivably be measured with thermocouples, but the atmosphere is usually strongly reducing, a condition well known to be destructive to the accuracy of the customary high-temperature couples. In some plants, periodic readings are taken with an optical pyrometer sighted into the top of the combustion flues. This is a useful measure for safety and general control, as it tends to prevent the damage that would result from overheating of the ovens. It does not, however, tell much about the temperature of the coke itself, because of the continually changing gradient in the wall between the coke and the combustion chamber. The best indication of the temperature of the coke itself must therefore be obtained by observation of the product as it is pushed out of the oven. The human eye is very sensitive to variations in brightness of a surface, and particularly to differences in brightness over a continuous hot surface.

Jan 1, 1943

By R. Silverman, H. Blumenthal

It was found that despite the similarity of chemical analyses of different titanium carbides used as base materials for cermets, the physical properties, especially transverse-rupture strengths, of test bars were different. Hence this metallographic study attempts to link physical properties to micro-structures. It is shown that microstructure, grain shape, and grain growth are functions of three interrelated factors: 1—powder production procedure, 2—surface conditioning of the particles, and 3—impurities either contained in the original powder or acquired during ball milling. An explanation is offered for the "coring effect," long observed, but heretofore of unknown origin. The explanation is based on assumption of an oxide film and on chemical analyses which substantiate these findings. TITANIUM carbide has become in recent years a material of great interest in the high temperature field. Consequently, many manufacturers in the United States and Europe are producing titanium carbide for cermet applications as well as for additions to the well known tungsten carbide tools. All present commercial processes of titanium carbide production utilize the chemical reaction of titanium dioxide and carbon to form as nearly as possible stoichiometric Tic. This reaction is carried out in three ways: 1—in a menstruum of molten metal,' 2—in the solid state, either in a protective atmosphere2 or in vacuum;" or 3—in an are-melting operation. In spite of the fact that the pure carbides obtained in these operations are almost identical chemically, the physical properties vary considerably when they are combined with a binder (Ni, Co) to form cermets. This fact led the authors to examine metal-lographically nickel-bonded titanium carbide in order to find the possible reasons for this behavior. Materials and Methods Five different titanium carbides were used in this investigation. They are identified in Table I. The first four materials were used in the as-received condition. Material E, received in lumps, was crushed to —100 mesh and carried through a flotation process in order to bring its graphite content in line with the other products. A Galagher flotation cell was used with pine oil as frothing agent. The chemical analyses of the investigated materials are given in Table 11. The binder used was carbonyl nickel of 9 to 14 microns particle size, supplied by A. D. Mackay. The materials were ball milled at a ball to charge ratio of 6:1 using procedures described under "Experiments and Results." All particle sizes mentioned are averages determined with a Fisher Sub-sieve Sizer. Test bars (lx0.40x0.16 in.) were prepared by 1—hot pressing to 85 to 95 pct of theoretical density at pressures between 1 and 1½ tsi and temperatures from 1600" to 1800°C, 2-—-cold presssing after 3 pct camphor had been added, or 3—wet pressing, both 2 and 3 at pressures between 5 and 10 tsi. All pressed bars were sintered in a vacuum of 105 to 10-6 mm Hg for 2 hr at 1350 °C. Transverse-rupture strengths were determined by breaking on a Baldwin Universal Testing Machine over a 9/16 in. span. Densities were measured by water displacement. The preparation of the specimens for micrographs was done according to Silverman and Doshna Luscz." All magnifications are at X1000. A sodium picrate electrolytic etch was used. Experiments and Results The influence of ball-milling procedure, ball-milling medium, pressing procedure, and sintering procedure on the microstructure of 80/20 — TiC/Ni were investigated. Ball Milling of Materials A, B, and C in a Steel Mill: Figs. 1 and 2 show microstructures of hot-pressed and vacuum-sintered test bars of materials A and B after the respective materials had been ball milled to 2.1 microns particle size in a steel mill and mixed with 20 pct Ni binder. Material A (Fig. 1) shows considerable grain growth. Also evident is a tendency of the carbide grains to coalesce. The density is 98 pct and the low transverse-rupture strength of 111,000 psi is probably caused by many large grains and an unfavorable packing factor. Almost all grains show a slight indication of "coring." Material B (Fig. 2), although showing grain growth, still has many small particles and a better distribution of binder and carbide due to the relative absence of the coalescing tendency. "Coring" can be observed in almost all grains. The high transverse-rupture strength of 179,000 psi and the density of 100 pct are believed to be due to the many small grains completely surrounded by the binder phase. There is also a preference to form spherical grains with material A, while most grains of material B preserve their angular shapes. Material C, of which no picture is given, stays between A and B in every respect. Rounding of some grains can be observed as well as coring, but the latter to a lesser degree than with material B. Its densification is good and the transverse-rupture strength obtained is 142,000 psi. Ball Milling of Materials A, B, C, and E in a WC Mill: When the Tic powders were ball milled to 2 microns particle size in a we mill, then ball-mill mixed with 20 pct Ni binder, hot pressed, and vacuum

Jan 1, 1956

By Bruce A. Kennedy

Lufthansa flight 497 roared down the runway and climbed rapidly through the early morning mist hanging over Pudahuel airport and the city of Santiago, Chile, into the brilliant sunlight above the clouds. As the plane banked onto course for Lima, Peru, we got what was possibly our last look at the beautiful snowclad mountains that ring Santiago. To the northeast was the massive hump of Aconcagua, the highest mountain in the Southern Hemisphere, wreathed in clouds and virtually looming over Rio Blanco, the new mine put into production by Cerro de Pasco just one short year before. Almost a thousand miles to the north lay the massive open pits of Chuquicamata and Exotica, and a little closer to Santiago the El Salvador mine. Behind to the southeast, clinging to the steep slopes of the Andes, was the large and awe-inspiring El Teniente mine at Braden. These mines, once the bastions of such companies as Anaconda and Kennecott, had a new owner-the Government of Chile. On the plane were a number of people who had spent a large part of their lives in Chile operating these mines and plants, and who now were suddenly faced with the necessity of starting new lives somewhere else. To them, this was their last look at the country which not too long ago was their home, a bittersweet moment of reminiscence and a time for questioning what the future held.

Jan 1, 1971

By H. W. McCue

In 1944, in the Texas Panhandle, 245 oil wells were drilled with a total daily initial production of 32,886 bbl., representing an average initial production of 134 bbl, per well. This was an increase over 1943 of 121 wells drilled, and an increased initial production of 13,861 barrels. On Dec. 31, 1944, the field was operating on an allowable of 113,567 bbl. per day, but actually was producing 85,539 bbl. per day from the 5901 oil wells. The tota1 production for the year was 33,439,436 bbl., bringing the cumulative total to 5.04,537,048 barrels. Gas Sixty-three gas wells with a combined open flow of 992 million cu. ft., were drilled during 1944. This was an increase of seven wells over 1943, but a drop of 216 million cu. ft. in initial open flow. The

Jan 1, 1945

By H. F. Yancey

AT the annual meeting of this Institute held two years ago a new method, of estimating the grindability of coal was described, based on experimental work carried on by the Bureau of Mines at its Northwest Experiment Station. Since that time, several organizations concerned with the testing or utilization of coal as pulverized fuel have adopted and used the method in determining the grindability of several hundred samples of coal. In addition, a series of comparative tests of this method and three others has been carried out in five laboratories under the auspices of Committee D-5 of the American Society for Testing Materials. As a result the Committee has recommended that the Bureau of Mines method, designated as the "ball-mill method," and the Hardgrove method2, previously advanced, be accepted as tentative standards3. Since the ball-mill method was originally developed and published, an opportunity has been presented to apply it to a larger number of coals and to study intensively some of the principles upon which the method is based. This paper presents a resume of these further studies and includes a comparison with the Hardgrove-machine method. Trial runs were also made with another procedure recently proposed-the C.I.T. roll-test method4.

Jan 1, 1936

By Stirling Huntley, R. H. Johnson

Pennsylvania will be remembered, as long as oil is produced, as the cradle of the industry of petroleum in North America. It was on Oil Creek, near Titusville, Venango Co., that Col. Edwin L. Drake, superintendent for the Seneca Oil Co., brought in the first commercial oil well on Aug. 28, 1859. Great difficulty was experienced in getting the well down to the producing depth of 69 ft. (21 m.) with the spring-pole system then in vogue for punching shallow water wells, so the novel expedient of driving an iron tube through the surface clays and quicksand was finally resorted to. The well had an initial yield of 25 bbl. a day on the pump, but soon went off, though 2000 bbl. were produced by the end of the year. With the Drake well a success, a young industry sprang into being, the rapid growth of which has been second to none in the country and the value of whose product is only surpassed by that of coal. For years the only producing territory, the Pennsylvania-New York field attained its greatest production in 1891, when the bringing in of the McDonald pool, between Pittsburgh and the West Virginia line, gave a total of over 33,000,000 bbl. At present the field, combined with West Virginia and southeast Ohio, gives 25,000,000 barrels. Geology and Stratigraphy In general, the Appalachian field is a huge geosyncline, the axis of which runs roughly northeast-seuthwest, from north of the New York state line south through Brookeville, Kittanning, Pittsburgh, Washington, through the southwest corner of the state of Pennsylvania into West Virginia. Minor folding has accompanied or followed the dominant fold of the field, and it is from these structures near the Pennsylvania-West Virginia line and their influence on the accumulation of oil and gas that I. C. White, state geologist of West Virginia, obtained his evidence for anticlinal guidance of prospecting. Many horizons in the geologic column of the field serve as reservoirs, and there arc several pools that have wells producing side by side from different and widely vertically separated strata. The strata show a promising succession of porous sand and conglomerate horizons alternating with numerous gray and dark brown 01. black shales, admittedly

Jan 1, 1921

By A. B. Dyes

In the operation of a water-driven reservoir, a free gas saturation can he established by maintaining production rates fast enough to cause the reservoir pressure to decline below the bubble point. The benefit of such a procedure on the displacement efficiency of the oil by water is illustrated for two types of sandstone samples from one reservoir. Those rock samples showing the poorest recovery to water drive in the absence of a free gas saturation give the most improvement in the presence of a free gas saturation. Employing one type of reservoir fluid (low .shrinkage) the benefit of evolved gas on oil displacement is calculated at several reservoir pressures below the bubble point. This demonstrates the presence of air optimum pressure for water displace,rnent which is .several hundred pounds per .square inch below the bubble point. Displacement of oil at the optimum pressures results in the removal of 7 to I? per cent more oil than would be obtained by displacement at the bubble point pressure. In some instance. this magnitude of increase may be worthy of consideration in establishing the maximum efficient rate of production from many water-driven fields. INTRODUCTION For many years the belief that the use of gas could be combined with that of water to result in a better recovery operation than the use of either of these phases alone has been prevalent in the oil industry. This is evidenced by the several field trials which have employed the injection of gas and water in combination.1.2.v In most cases the small amount of any additional recovery, in combination with the limited knowledge available on the older reservoirs, has left uncertain the influence of gas on recovery in these earlier attempts to combine the use of gas with water. Research studies in recent years have demonstrated through laboratory. floods the magnitude of the benefit of the presence of gas on the displacement of oil from sandstones by water.5,6,7,8,9,10,11 In addition, studies of the distributions of the phases which are present during the displacement process have developed concepts concerning the mechanism by which this benefit is obtained."." It now remains for the engineer to incorporate these findings into the general technology of reservoir operations. It is the purpose of this paper to illustrate that the production of a water-driven reservoir at pressures below the bubble point is one such operation whereby improved oil displacement efficiency can be obtained as a result of gas evolution. The establishment of a gas saturation by evolution of dissolved gas was one of the techniques used by several investigators in the laboratory studies. The possibility of obtaining the benefit of gas evolution in water-driven reservoirs by producing at pressures less than the bubble point has 3150 been pointed out previously." The desirability of this operation has undoubtedly

Jan 1, 1955

V. R. GARFIAS,* Palo Alto, Cal. (written discussion?).-Regarding the statement of Mr. Ordoñez, on page 1007, concerning the synclinal curving of sedimentary beds caused by the extrusion of volcanic necks, that "this phenomenon might occur, but it is not fully proved in our fields," I beg to reply that the funnel and anticlinal-ring structure is actually associated with igneous intrusions in the Mexican oil fields, as we were able to ascertain by plotting an underground contour map and making a structural model of the oil-bearing beds of the Ebano field. E. DE GOLFER, New York, N. Y. (written discussion?).-The paper under discussion is not only of interest in connection with its subject but it is a contribution of considerable importance to our knowledge of the possible effect of igneous rocks upon the accumulation of petroleum in the Mexican fields.

Jan 10, 1918

By Donald Barton

THE theory of gravitation is based on Newton's law that any two bodies exert a mutual attraction which is proportional to the product of their masses and inversely proportional to the square of the distance between them; i. e., A = K MM/R2 (1) where K is a constant, M and m are the respective masses of the two bodies, and R the distance between them. In the earth's gravitational system, the earth is one of the bodies; the other may be any body within or without the earth. In theoretical discussions and calculations in regard to gravity, that other body usually is taken as a unit of mass: in the C. G. S. system, a body of one gram in mass. GRAVITY AND LEVEL SURFACES Gravity is defined in geophysics as the force of attraction exerted by the earth, towards itself, on a body of unit mass. The intensity of gravity is usually expressed in dynes of force or in centimeters of acceleration. In geophysical work in America; most commonly it is expressed in dynes (per gram) with the "per gram" understood and not directly expressed. In geophysical work in Europe, most commonly it is expressed in centimeters per second per second (cm./sec.2) and less commonly merely as centimeter-gram-second units (C. G. S.). At sea level, the intensity of gravity amounts very nearly to 980 dynes. The vertical is the direction along which the attraction of gravity is exerted at any point. In most cases, it is very nearly, but not quite, perpendicular to the earth's surface. The path that would be taken by a body falling freely through space toward the earth is vertical at each point and may be spoken of also as "the vertical," or as the line of the vertical, or as a line of force of gravity. At the earth's surface it commonly is very nearly, but not quite, a straight line.

Jan 1, 1928

By R. Neilson Clark

THE coal-beds of Canyon City are situated six miles below the town, upon the Arkansas River. At this point the Rocky Mountains have thrown out from their main ridge two spurs. The one to the north, containing Pike's Peak and Cheyenne Mountain, is known as part of the "Rim Range;" the one to the west and south is known as the "Greenhorn Range." Against these syenitic mountains, the later rocks are piled and uplifted ; at right angles to the direction of this main uplift is the axis of a lesser plication. On the north, west, and south, the pitch is steep, gradually flattening as it approaches the centre of the basin and rising again to the east at a pitch of about 5", thus forming a perfect basin, the centre of which is only three miles east of the base of the Greenhorn Range.