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By E. P. Klier

The work of Klier and Lyman1 on the bainite reaction has led to the full description of this reaction for medium-carbon low-alloy steels. Certain experimental data reported by Klier and Lyman appear, however, to be improbable of obtaining in very high-carbon steels. The study herein reported consists of an analysis of the transformation characteristics of a 3 per cent chromium, I per cent carbon steel by means of X-ray and metallographic methods. From the results obtained it is concluded that the bainite reaction in this steel is more complicated than that reported by Klier and Lyman for the low-carbon low-alloy steels. Henever, the mechanism of bainite formation in this steel appears to be essentially the same as proposed for the low-carbon low-alloy steels with the modification that the first volumes to transform are carbon-rich rather than carbon-poor. Experimental Procedure The analysis of the steel studied was: Cr, 2.89; C, 1.02; Mn, 0.33; Si, o.35; S, 0.012; P, 0.020. The stock was received from the Carpenter Steel Co. in rolled bars. Specimen Preparation Specimens were austenitized at 1200°C. (2192°F.) for 25 min. in purified nitrogen. The resultant A.S.T.M. austenite grain size was 0-1. Isothermal transformation was allowed by quenching the specimens into liquid metal baths controlled to 5°C. at 540°C. (1004°F.) and above, and to 2°C. at 490°C. (914°f.) and below. Following the desired degree of transformation all specimens were water quenched. Metallographic Examination Specimens 1/4 in. round by 1/4 in. were used for nietallographic examination. Etch-ants used were Vilella's reagent (I gram picric acid, 10 ml. hydrochloric acid to make 100 ml. ethyl alcohol solution) and alkalinc sodium picratc (electrolytic). Vilella's reagent was effective in revealing all microconstitucnts, while the alkaline sodium picrate developed the carbon-rich structures or carbides only. X-ray Examination Two X-ray techniques were used—the Debye-Scherrer method and a back-reflection method. 'The small specimens necessary for the Debye-Scherrer method were austenitized and then allowed to transform, or were cut from the larger metallographic specimens. The metallographic specimens were used for the back-reflection X-ray analysis. When it was desirable to determine the structure of the carbide present, sliver specimens were electrolytically etched to develop a carbide coating, then were exposed in the cameras. This technique was frequently necessary to allow positive identification of the carbide.

Jan 1, 1945

By C. W. Phillips, R. S. Busk

With most cast metals the grain size may vary within wide limits, depending upon the conditions at the moment of freezing. These conditions are subject to control in magnesium-base alloys, by proper melting and superheating techniques, enabling production of quite uniform and fine-grained castings, almost independent of section thickness. However, such variations of grain size as do exist, in common with all metals, are reflected in corresponding changes in mechanical properties. It is the intent of this paper to present data giving the relationship between grain size and mechanical properties. Data are also included on the combined effects of grain size and micro-porosity. In addition, a short discussion of factors influencing the grain size of sand castings is included. Measurement OF Grain Size By grain size is meant the statistical distribution of volumes occupied by the individual crystallites in a metal section. Since this is almost always impossible of direct measurement, several methods of estimating and expressing the size have been evolved. Most exact methods make use of the microscope. This involves study of a single plane cut at random through the metal. What is seen in the microscopc are polygons, each the cross section of a grain. The diameters or areas of these polygons are then measured and the grain size is expressed as an average diameter, number of grains per unit area, average area per grain, or, rarely, average volume per grain. Rutherford, Abom, and Bain3 have discussed extensively the errors involved when using a plane section to estimate volume. They clearly point out that the tendency is to underestimate the true grain size because of the nature of the measurcment. The A.S.T.M. recommends that measurement be made by comparison with a standard chart, by means of Jeffries' planimetric method4 or Heyn's intercept method. The Society recommends that the notation be in terms of the number of grains per unit area (as is the grain-size number used for steel) or as an average diameter, expressed in inches or millimeters (as for copper and brass). The method of measurement used for this study was comparison with a standard chart, which has been described by P. F. George.5 The chart was constructed by photographing at Ioo diameters a uniform specimen with an average grain diameter of 0.003 in. The average diameter of this specimen was determined by numerous measurements, using both the Jeffries and Heyn methods. The other grain sizes were then obtained by appropriate enlargemcnt of the master sample. Careful comparison of the chart method with other methods on identical samples indicates that though the differences be-

Jan 1, 1945

By C. W. Phillips, R. S. Busk

WITH most cast metals the grain size may vary within wide limits, depending upon the conditions at the moment of freezing. These conditions are subject to control in magnesium-base alloys, by proper melting and superheating techniques, enabling production of quite uniform and fine-grained castings, almost independent of section thickness. However, such variations of grain size as do exist, in common with all metals, are reflected in corresponding changes in mechanical properties. It is the intent of this paper to present data giving the relationship between grain size and mechanical properties. Data are also included on the combined effects of grain size and microporosity. In addition, a short discussion of factors influencing the grain size of sand castings is included. MEASUREMENT OF GRAIN SIZE By grain size is meant the statistical distribution of volumes occupied by the individual crystallites in a metal section. Since this is almost always impossible of direct measurement, several methods of estimating and expressing the size have been evolved. Most exact methods make use of the microscope. This involves study of a single plane cut at random through the metal. What is seen in the microscope are polygons, each the cross section of a grain. The diameters or areas of these polygons are then measured and the grain size is expressed as an average diameter, number of grains per unit area, average area per grain, or, rarely, average volume per grain. Rutherford, Aborn, and Bain3 have discussed extensively the errors involved when using a plane section to estimate volume. They clearly point out that the tendency is to underestimate the true grain size because of the nature of the measurement. The A.S.T.M.. recommends that measurement be made by comparison with a standard chart, by means of Jeffries' planimetric method' or Heyn's intercept method. The Society recommends that the notation be in terms of the number of grains per unit area (as is the grain-size number used for steel) or as an average diameter, expressed in inches or millimeters (as for copper and brass). The method of measurement used for this study was comparison with a standard chart, which has been described by P. F. George.', The chart was constructed by photographing at i00 diameters a uniform specimen with an average grain diameter of 0.003 in. The average diameter of this specimen was determined by numerous measurements, using both the Jeffries and Heyn methods. The other grain sizes were then obtained by appropriate enlargement of the master sample. Careful comparison of the chart method with other methods on identical samples indicates that though the differences be-

Jan 1, 1945

By D. Turnbull, J. H. Hollomon, J. C. Fisher

UNDERSTANDING of the diffusion problem has recently been furthered by the analysis of Birchenall and Mehl.1 They pursued the problem of the variation of the diffusion coefficient with composition for non-ideal solid solutions. Their analysis follows the tradition of Wagner,2 Jost,3 Dehlinger,4 and Darken,' who assumed the net flux of dif¬fusing material to be proportional to the gradient of a quantity related to free energy. The basic assumption in Birchenall and Mehl's formulation of the problem is that the net flux of diffusing material is proportional to a thermodynamic activity gradient. To estimate the applicability of the derived relations, they corrected the diffusion coefficients of carbon in austenite by utilizing Smith's' activity data for carbon, and the diffusion coefficients for zinc in copper with activity data computed from the vapor pressure measurements of Hargreaves.7 The corrected coefficients for carbon were virtually independent of carbon concentration. For the diffusion of zinc in copper a moderate variation of diffusion coefficient with concentration remained after the correction. The problem of diffusion can be formulated in another way than that used by Birchenall and Mehl. The method is that of chemical rate theory and has been used by Eyring and his coworkers8,9 as well as by Eyring and Zwolinski10 in a discussion to Birchenall and Mehl's paper. As yet the method has not been applied to substitutional solid solutions. On the basis of their assumptions, Eyring and Zwolinski derived a relation between the diffusion coefficient and activity that is identical with that of Dehlinger and Darken but which does not correct for the variation of the diffusion coefficient with concentration as well as does the relation derived by Birchenall and Mehl. It was thought that the theory of diffusion would be more complete if the inconsistency between the two analyses could be rationalized and if diffusion in substitutional alloys were analyzed on the basis of the concepts of the chemical rate theory. CHEMICAL RATE THEORY According to the theory of absolute reaction rates8 the reaction [A,+A2+ ... +.A;->X,+X2 +...+X; EqI] is viewed as taking place in two steps. First the reactants A1, A2, . . . A[i] combine to form an activated complex M with which they are in equilibrium; [A, + A2 + .. . + Ai = M. Eq 2] Second the activated complex decomposes to give the products X1, X2. . .. X[j]; [M->X1+X2+ ... +.X;. Eq3] It has been shown8 that the number of activated complexes decomposing per unit volume per unit time is given by the expression† [kT]

Jan 1, 1948

By Arthur L. Christenson, Clarence E. Jackson

In the establishment of the relationship between weldability and hardenability, two methods have been employed in correcting for the grain growth produced in the heat-affected zone: first, the hardenability calculated from chemical composition* may be corrected to the grain size observed in an actual weld? or, second, a hardenability test may be made on the steel quenched from a temperature high enough to produce a grain size comparable to that found in the heat-affected zone.8 In order to obtain grain sizes in the end-quench hardenability bar comparable to those resulting in the base metal from the welding cycle, a quenching temperature of 2Ioo°F. has been used. In studies of the end-quench hardenability specimen quenched from 2Ioo°F. instead of from a lower temperature of I7OO°F., it is impor-TaiiT to ascertain The relative cooling rates for various distances along the bar. It is a question as to whether the cooling occurs at the same rate or whether there is any significant difference from the standard cooling-rate curve published by Jominy and confirmed by others.4,5 This paper reports experimental evidence concerning the effect of quenching temperature on the cooling rates in the end-quench hardenability test. The effect of quenching temperatures on cooling rates has been studied by a number of investigators.6'7 French has considered this effect from both theoretical and experimental aspects. In French's studies on complete quenching of spheres and rounds, an increase in the quenching temperature caused an increase in the cooling rate at 720°C. at the center of the specimen. The center cooling velocity also has been shown to be dependent upon the surface per unit volume for the type of specimens studied; the velocity of cooling increases with an increase in the surface per unit volume. Three methods of indicating the rapidity of cooling of a body of metal during a quenching operation have been propped: I. The time it takes for the metal to cool from the quenching temperature to a temperature halfway between the quenching temperature and the temperature of the quenching medium (half-temperature time): Grossmann, Asimow and Urban7 justify the use of this criterion by the fact that the half-temperature time includes the temperature and time of incubation as well as the zone of formation of pearlite and, further, the data so derived accord very closely with experimental values. 2. The time interval the metal remains in a given temperature range; for example,

Jan 1, 1944

By Arthur L. Christenson, Clarence E. Jackson

In the establishment of the relationship between weldability and hardenability, two methods have been employed in correcting for the grain growth produced in the heat-affected zone: first, the hardenability calculated from chemical composition* may be corrected to the grain size observed in an actual weld? or, second, a hardenability test may be made on the steel quenched from a temperature high enough to produce a grain size comparable to that found in the heat-affected zone.8 In order to obtain grain sizes in the end-quench hardenability bar comparable to those resulting in the base metal from the welding cycle, a quenching temperature of 2Ioo°F. has been used. In studies of the end-quench hardenability specimen quenched from 2Ioo°F. instead of from a lower temperature of I7OO°F., it is impor-TaiiT to ascertain The relative cooling rates for various distances along the bar. It is a question as to whether the cooling occurs at the same rate or whether there is any significant difference from the standard cooling-rate curve published by Jominy and confirmed by others.4,5 This paper reports experimental evidence concerning the effect of quenching temperature on the cooling rates in the end-quench hardenability test. The effect of quenching temperatures on cooling rates has been studied by a number of investigators.6'7 French has considered this effect from both theoretical and experimental aspects. In French's studies on complete quenching of spheres and rounds, an increase in the quenching temperature caused an increase in the cooling rate at 720°C. at the center of the specimen. The center cooling velocity also has been shown to be dependent upon the surface per unit volume for the type of specimens studied; the velocity of cooling increases with an increase in the surface per unit volume. Three methods of indicating the rapidity of cooling of a body of metal during a quenching operation have been propped: I. The time it takes for the metal to cool from the quenching temperature to a temperature halfway between the quenching temperature and the temperature of the quenching medium (half-temperature time): Grossmann, Asimow and Urban7 justify the use of this criterion by the fact that the half-temperature time includes the temperature and time of incubation as well as the zone of formation of pearlite and, further, the data so derived accord very closely with experimental values. 2. The time interval the metal remains in a given temperature range; for example,

Jan 1, 1944

By I. L. Dillamore

A purely geomentrical analysis based on oriented-growth relationships is presented to derive annealing-texture orientations in bcc metals from their- known deformation textures. The analysis takes as its starting point a description of- the bcc deformation texture and follows previous work on fcc metals in considering pvobable nurleation sites for recrystallization and the textural limitations on grains growing into a deformed matrix. The analy-sis accounts for the prominent and the minor coinponents of the annealing textures formed from two the deformation textures and can account for the ob-sem:ed temperature dependence of the annealing texture of bcc metals. THERE have been a number of investigations of annealing textures in bcc metals but few attempts to relate these textures to the deformation textures. This has been largely due to the lack of definition of both annealing and deformation textures, neither of which shows sharply defined orientations. It is, however, necessary to get a better understanding of primary recrystallization textures in bcc metals in view of increasingly exacting demands upon the quality of steel sheet for drawing purposes and as a necessary step towards the control of textures through processing. An analysis is presented here which relates annealing textures to deformation texture, by a purely geometrical method. This takes as its basis the oriented-growth theory of recrystallization and makes some reasonable assumptions regarding the make-up of bcc deformation textures and the limitations on growth relationships in bcc metals. Detailed information on this latter point is not available at the present time, and the present analysis may need to be streamlined or extended when such information is at hand. It is felt, however, that despite these limitations the analysis provides useful results and a valuable aid towards understanding the effect of processing variables. 1) BCC ROLLING TEXTURES Different workers have used a variety of descriptions for the texture developed in bcc metals by rolling. For the present purpose it will be assumed that two different deformation textures can be obtained: 1) a texture containing a major (112)[li0] component and a minor (001)[1i0] component for which increasing deformation causes the (001)[li0] component to increase at the expense of the (112)[li0] component, as suggested by Dillamore and ~oberts' (this is the texture predicted to arise starting from randomly oriented material); 2) a t~xture containing the above components and (111)[110] and (ii1)[112] components. This texture could arise from a material with an initial (110)[001] or (iil)[112] texture. It is well-known that the (ll0)[001] orientation rotates to (ii1)[112]that on roll-

Jan 1, 1965

By W. B. Humes

The use of high vacuum on a large industrial scale in the ferrosilicon process for the production of magnesium marks the coming of age of an important new metallurgical technique. The economical production of reactive metals, such as magnesium, which combine with all the well-known furnace atmospheres, has until recently been successfully carried out only by electrolytic methods. It is now apparent that, through the use of high vacuum, the distillation or sublimation of many metals can be done industrially at much lower temperatures, and hence in much simpler equipment, than heretofore has been thought possible. At the beginning of the present emergency, when the ferrosilicon process of producing magnesium was brought to the fore, little was generally known about vacuum engineering, practices, and techniques. In a comparatively short time, the available equipment has been adapted, new equipment designed and built, and a fund of know-how evolved to make possible the production of thousands of pounds of magnesium per day at pressures less than 1/ r0,000 of an atmosphere. Pilot-plant operations have been consistently maintained at pressures even as low 2s one micron (0.001 mm.). These low pressures, which previously were regarded as prohibitively costly or impossible to attain, have been demonstrated as economically feasible on an industrial scale. Necessity for Vacuum The main function of vacuum in the ferrosilicon process, and hence in most vacuum smelting processes, is to lower the temperature at which the metal may be distilled or sublimed from the reduction mixture. A secondary function is to protect the distilled metal from attack by the furnace atmosphere and to permit the formation of a dense condensate. In the ferrosilicon process, magnesium is formed by the reaction between dolomite and ferrosilicon: 2(Mg0-Ca0) -\- HFeSU / t=> aMg + MFe + (CaO)2-SiO2 The metal is distilled from the pelleted charge at a free air pressure of about 0.100 mm. of mercury (100 microns). This low pressure is not needed for the reaction, but rather serves to protect the metal vapor from the oxygen or nitrogen of the atmosphere and permits the formation of a condensate free of pyrophoric material. The reaction proceeds at air pressures as high as several millimeters of mercury, and evidence has been offered to show that the actual equilibrium pressure of magnesium at operating temperatures of 2I50°F. is somewhat higher. Experimentation indicates that the yield begins to decrease at pressures above 500 microns. While no real operating data are yet available on the relationship between

Jan 1, 1944

By R. S. McFarland

OKLAHOMA, in 1924, recorded the largest single increase of any state; the total oil production for the year being 176,206,397 bbl. (Oil & Gas Jnl.), which gives an increase over 1923 of about 9 per cent. Oklahoma ranked second in total amount, California being first, and produced almost 25 per cent. of the total production of the United States. This gain in production is accounted for entirely by the rapid development, deeper drilling, and efficient management of productive areas known at the beginning of the year, for, due to the small number of wells drilled, few new pools were discovered and developed up to any important stage during the year. Three major pools, Burbank, Tonkawa and Cromwell, furnished 37 per cent. of the total production. Burbank led by a wide margin, having the largest production of any single pool; there was a steady increase in production until September. The close. development of the pools in Okfuskee, Seminole, and Hughes Counties, together with the new deep-sand production at Tonkawa and increased drilling operations in Osage County, accounted for the big increase shown during the year. In January, 1924, the shutdown movement and curtailment of production in Hewitt and Tonkawa, which had been effective during the year of 1923, were stopped. The shutdown movement and curtailment of operations in 1923 does not give a fair comparison with 1924, as undoubtedly a great deal more oil would have been produced in 1923 had it not been for these measures. The sensational developments during the year, which were certainly beyond the prediction of the oil industry, were the Cromwell field, which started the year with 10,478 bbl. for January and increased rapidly to 1,267,032 bbl. for. December, and the discovery of the Wilcox productions below 4000 ft. in the Tonkawa field in May, which by the end of the year had produced 11,650,000 bbl. In this connection, it can be safely said that 1924 was a banner year for the Wilcox sand series; it has been estimated that between 40,000,000 and 50,000,000 bbl. of the production for the year came from this sand. Although numerous Wilcox pools were opened throughout the state, the big Wilcox production came from. the Tonkawa and Stroud pools. Oklahoma's deepest well, the Kingwood Oil Co. No. 1 Barnett in the northwest corner of the northeast quarter of the southeast quarter of Sec. 7 T. 7 N. R. 10 E., Hughes County, was abandoned in January, at 5281 ft. with numerous good shows recorded, which have stimulated-further drilling in the locality.

Jan 3, 1925

By Paul A. Schafer

BALATOC mine, the principal gold-producing mine in the Philippines, is 10 miles southeast of Baguio, in the Cordillera Central of northern Luzon.1 The region is a deeply dissected plateau, ranging in altitude from 3000 t0 5000 ft. above sea level. The rocks consist chiefly of granodiorite, diorite, and remnants of metamorphosed sediments, cut by dikes of andesite porphyry and quartz-diorite porphyry. All are intruded by a volcanic breccia plug, oval in horizontal section, about 3200 ft. long and 2300 ft. wide, which is the north central part of the mineralized area. Three main vein systems have been developed (Fig. 1): q6, 231 and 364, which strike about N.70°E. and dip 5o to 90°S. Each system is a braided zone consisting of many individual components. They are disturbed by a series of premineral faults or shear zones striking about N.45°E. Twelve of these produce important effects on the persistence, character, and quality of veins. From west to east the faults are named (after claims): Hog, Big Gun, Bull, Pine, Lolita, Bar No. I, Bar No. 2, Curt, Sun, Helen, Itoe, and Frog. They are early breaks formed prior to the N.70°E. vein fractures. Mineralization occurs on them but, with several prominent exceptions, they are too low grade to mine. A number of northwesterly striking faults complete the structural pattern. Although they are relatively abundant, the effect on the veins is so small that they do not present any problems in mining or development. All of these faults that have been observed are later than the N.70°E. veins and offset them to the left. NORTHEAST FAULTS The early northeast faults* are notably continuous in spite of their small displacements, 20 to 100 ft. Frequently they appear so weak that their importance is masked and their identity clouded. The gouge along any of these faults may vary from exceedingly weak at one point to very strong at another point only a short distance away. In other words, the amount of gouge depends on the changes of attitude of the fault plane, and is no indication of the extent of the movement. Places where walls are spread apart are filled with gouge squeezed from tight places. Also, mineralization sometimes obscures fault gouges by replacement. The mineralization of northeast faults has produced several important ore bodies; namely, 231 west on Pine fault and q6 vein on the same fault. To a smaller extent, Lolita, Curt, Bull, Bar No. I, and Sun

Jan 1, 1942

By R. P. Rothwell

AT this our first meeting I beg to call the attention of the members of our Institute to what is certainly a question of the greatest possible importance to the industries we represent; and more particularly to the welfare of the coal and iron trades: I refer to the enormous waste of coal in mining and in its preparation for market, as now practised in our anthracite coal-fields. I t is a fact which many of you can certify to, that we are wasting fully me-half of all the coal in the veins we are now working, and there are cases, which might be mentioned where this proportion, immense as it is, has been greatly exceeded. The popular belief that our deposits of anthracite coal are "practically inexhaustible," is very far from being founded on facts. On the contrary, supposing the present rate of increase in the production to be maintained, it is probable that a maximum yield for our coal-fields would be attained in about fifteen years ; there are in fact some of our smaller basins where the principal veins are nearly exhausted and the production has already attained its maximum. There are others, again, where the depth attained-and it must be borne in mind that we commenced working at the surface outcrop moderate though it is (scarcely ever reaching eight hundred feet), has so increased the cost of mining as to imperil the capital invested, and though it requires but little foresight to predict the time when the difficulties of mining will be very considerably increased by reason of the greater depth, greater quantity of water, fire-damp, and other fruitful sources of cost, yet, ignoring these recognized facts, we continue to waste more than one-half of the coal where it is obtained with the least danger, expense, and trouble, that is, near the surface-either above water-level or at a moderate depth . below it. The inspection of almost any accurate mine map will satisfy you that, on an average, we leave fully one-third. of the coal in the ground as pillars to support the roof; in some places more than one-third thus remains, while it is very rare that less than one quarter is left. In almost every case this coal is absolutely lost, for it will very rarely pay to reopen gangways and lay roads to it after that portion of the mine has been abandoned. Is it necessary in all cases to support the roof, and where it is, may not some artificial

By Max Roseler

THE CHAIRMAN (WILLIAM KELLY, Vulcan, Mich.).-Some 8 or 9 years ago I was at Daiquiri, only a. few miles east of Firmeza, where there are deposits of iron ore of the same general character. There is a great conical hill, perhaps 800 or 1,000 ft. in height and the ore deposit appears to be somewhat in a canoe shape on one side of the hill. The mining has been done by quarrying the ore in benches. These are called levels and to go to the 10th level it was necessary to take mules and ride to the top of the hill, which was to me an upside down arrangement of numbering levels and a novel method of entering and viewing a mine. A little copper ore can be seen in places, and not being a geologist I thought the deposit might possibly be a gossan, but none of the geologists who have written on the subject approve of this hypothesis and the great question seems to be what part, if any, the limestones have played in the origin of ore; whether these deposits are replacements of limestone and whether they are contact ,deposits between the limestone and the other rocks. Examinations have been made by many eminent geologists and the problem has been discussed vigorously on both sides. The deposits are exceedingly interesting from a commercial standpoint and although they have been studied for a number off years the origin of the ore is still a difficult and somewhat controversial question. J. T. SINGEWALD, JR., Baltimore, Md.-I have had the privilege of visiting these deposits and have been very much interested in this paper, of Dr. Roesler's; having been on the ground, I can easily appreciate the difficulties under which he labored in attempting to work out the geology of that region, and he certainly deserves considerable credit for the way in which he has deciphered the geological relations of the Firmeza district. There are several points in his paper 1 ,would like to discuss; first, in regard to the geological interpretations. His differs from previous interpretations in the relative age of the diorite and the granite, but you will note that Prof. Lindgren suggests the probability. that those two rocks are very closely of the same age, and Prof. Kemp actually suggests, although he does not-accept the idea, that the granite is probably later than the diorite, so that there seems to be no particular reason

Jan 4, 1917

By T. E. Ockershauser

The Southwest Antioch Oil Field located in T2&3N - R2&3W, Garvin County, Okla., was discovered in February, 1946, by The Globe Oil & Refining Co. and The Vickers Petroleum Co. at their Melinda Gibson No. 1. Oil production was encountered at a depth of 6,525 ft in 14 ft of lower Pennsyl-vanian sandstone. The producing sand, locally called the ."Gibson" or "Third Deese," is a sand bar deposit strung along the west flank of the Pauls Valley uplift in a northwest-southeast direction. The oil reservoir is defined to the east by the edge of sand deposition along the uplift and to the west by the gradation of sand into shale. Within the Antioch Unit, the sand dips from 150 to 400 ft per mile southwesterly and has a pay thickness varying from 10 to 55 ft and averaging 28 ft. Several areas of Gibson production have been developed, including the Katie pool on the south, the Elmore Area of the Southwest Antioch Gibson Sand pool. the Southwest Antioch Gibson Sand pool proper, the Southwest Maysville pool and the New Hope pool on the north. Production extends over a belt 22 miles long by about two miles wide and is continuous except into the Katie and New Hope pools. It appears that drilling will soon prove these intervening areas productive. To March 1, 1950, approximately 18,000 acres have been developed with 450 Gibson wells. It is likely this count will ultimately reach 32.000 acres with 800 wells. RESERVOIR The natural production of oil from the Gibson reservoir is primarily due to solution gas expansion though gravity also plays a part. There is no indication of water drive or evidence that an initial gas cap existed. Gibson oil has a stock tank gravity of 43" API and was saturated at the original reservoir pressure of 2.925 psi. It contained 1,3440 cu ft of gas per bbl in solution and had a high shrinkage of 70 per cent. Connate water amounts to 15 per cent. Reservoir temperature is 130°F. Porosity averages 15.5 per cent and permeability ranges from less than one md to over 1.000. Based on meacurement of 400 core plugs from 15 wells, 78 per cent of the permeabilities fell within the 10 to 1,000 md bracket and averaged l67. Primary oil recovery is estimated at 140 bbl per acre-ft or 22 million bbl for the present 137-tract unit. Due to unitization

Jan 1, 1951

By T. E. Ockershauser

The Southwest Antioch Oil Field located in T2&3N - R2&3W, Garvin County, Okla., was discovered in February, 1946, by The Globe Oil & Refining Co. and The Vickers Petroleum Co. at their Melinda Gibson No. 1. Oil production was encountered at a depth of 6,525 ft in 14 ft of lower Pennsyl-vanian sandstone. The producing sand, locally called the ."Gibson" or "Third Deese," is a sand bar deposit strung along the west flank of the Pauls Valley uplift in a northwest-southeast direction. The oil reservoir is defined to the east by the edge of sand deposition along the uplift and to the west by the gradation of sand into shale. Within the Antioch Unit, the sand dips from 150 to 400 ft per mile southwesterly and has a pay thickness varying from 10 to 55 ft and averaging 28 ft. Several areas of Gibson production have been developed, including the Katie pool on the south, the Elmore Area of the Southwest Antioch Gibson Sand pool. the Southwest Antioch Gibson Sand pool proper, the Southwest Maysville pool and the New Hope pool on the north. Production extends over a belt 22 miles long by about two miles wide and is continuous except into the Katie and New Hope pools. It appears that drilling will soon prove these intervening areas productive. To March 1, 1950, approximately 18,000 acres have been developed with 450 Gibson wells. It is likely this count will ultimately reach 32.000 acres with 800 wells. RESERVOIR The natural production of oil from the Gibson reservoir is primarily due to solution gas expansion though gravity also plays a part. There is no indication of water drive or evidence that an initial gas cap existed. Gibson oil has a stock tank gravity of 43" API and was saturated at the original reservoir pressure of 2.925 psi. It contained 1,3440 cu ft of gas per bbl in solution and had a high shrinkage of 70 per cent. Connate water amounts to 15 per cent. Reservoir temperature is 130°F. Porosity averages 15.5 per cent and permeability ranges from less than one md to over 1.000. Based on meacurement of 400 core plugs from 15 wells, 78 per cent of the permeabilities fell within the 10 to 1,000 md bracket and averaged l67. Primary oil recovery is estimated at 140 bbl per acre-ft or 22 million bbl for the present 137-tract unit. Due to unitization

Jan 1, 1951

By P More

US 4,132,621-In the electrowinning of aluminum, the cells are aligned in a lengthwise direction so as to lessen the harmful influence of the induced magnetic fields Each cell is supplied with current from the preceding cell both via the head arid at least one side riser The output of the cathode bars is divided into two separate groups, the upstream group supplying the head of the subsequent cell arid the downstream group supplying the side risers of the subsequent cell This produces a substantial improvement in cell efficiency arid a greater regularity P Morel, J P Dugois, arid B Langon, assigned to Aluminium Pechiney. Jan 2, 1979 12 pp. (204¬243M) Filed 1-12-78 (868,861) Priority: France, 1-19-77 (77/2,213) US 4,134,806-Cells, anodes, arid methods for use in the electrowinning of nickel, cobalt, copper, zinc, or other metals from an acid ore leach solution or the like The cell is provided with vertically immersed stationary cathodes and stationary rod anodes which are noncorrodible by the electrolyte arid are electrocatalytic to the anode reaction. The spaced parallel anode rods are connected to electric current supply bars The anode rods have an electroconductive core made of a metal alloy arid a surface coating of an oxide of platinum or a platinum group metal The ratio of active cathode surface area to active anode surface area is preferably at least 3 0. De Nora arid C Traini, assigned to Diamond Shamrock Tech¬nologies, SA Jan 16, 1979 13 pp. (204-105R) Filed 9-15-77 (833,661) Priority Italy, 1-29-73 (19738 A/73). Same British 1,434,334-5, dated May 5, 1976 US 4,135,994-In the electrowinning of aluminum at a high current efficiency, the electrolytic bath is a mixed molten salt consisting of 2-15% by weight of aluminum trichloride, 15-83% of sodium chloride, 15-70% of combined calcium chloride arid magnesium chloride but riot more than 40% of calcium chloride, arid optionally up to 10% of barium chloride Preferably, plate-shaped graphite electrodes used for both cathodes and anodes are arranged in parallel inclined relation so that the axis in the lengthwise direction makes an angle of from 10° to 45° to the horizontal. T Ishikawa arid H Ichikawa, assigned to Nippon Light Metal Co Ltd Jan 23, 1979 4 pp (204-67) Filed 11-15-77(851,632) Same British 1,550,502, dated Aug 15, 1979

Jan 1, 1980

By Jasper L. Stuckey

HISTORY IT is not known when kaolin mining was first begun in North Carolina. Evidence, in the form of excavations and primitive tools, indicates that some of the deposits were worked in prehistoric times. It has been suggested that the prehistoric mining was for mica, but the workings were all in altered or partly altered pegmatite material and the dumps do not represent the amount of material removed. Some of the early openings may have been made in search of kaolin or semi-kaolinized feldspar which was sold to English1 traders along the coast and used in some of the early English porcelains. In 1944,2 an application was made for an English patent to produce porcelain from an earthy mixture obtained from the Cherokee Nation in North America. It is well established, however, that the occurrence of kaolin in western North Carolina was known in England by 1767. In that year, Josiah Wedgewood sent T. Griffiths3,4 to what is now Macon County, North Carolina, to secure a supply of kaolin for use in England. Griffiths diary, now in Etruria Museum, Stokes-on-Trent, contains a most interesting account of his experience. Kaolin was discovered at St. Austell, England, shortly after the voyage of Griffiths, which probably accounts for the lack of further interest in American kaolin. Between 1767 and 1888, there are no records of kaolin mining in North Carolina. In the latter year, however, mining was begun near Webster, Jackson County, and, in the intervening period, has become an important industry. For some 20 years, kaolin mining was carried on chiefly in Jackson, Macon, and Swain Counties. About 1904, it was begun in the Spruce Pine district and for the past 20 years most of the kaolin mined in the State has come from Avery, Mitchell, and Yancey Counties. DISTRIBUTION The kaolins of North Carolina are limited in occurrence to the Piedmont Plateau and Appalachian Mountain area of the State. While kaolins are widespread in the Piedmont Plateau, having been prospected for in Rutherford, Cleveland, Gaston, Granville, Lincoln, Catawba, Iredell, Richmond, Moore, Randolph, and Montgomery Counties, the production from that area has never been important. The known deposits of commercial importance are limited entirely to the mountain area of the State. While kaolins occur widely distributed throughout the mountain area and have been prospected for in many counties of that area, commercial production has come chiefly from two districts. One of these includes Jackson, Macon, Swain, and Haywood Counties. The other includes Avery, Mitchell, and Yancey Counties. GEOLOGY With few exceptions, all the known kaolin deposits in North Carolina contain

Jan 1, 1947

By Harry M. Mikami, Harold A. Heiligman

The term chromite is often used to cover all chrome ores and concentrates which are the designations actually employed by most industrial users and producers. Chromite is, of course, the predominant mineral in chrome ores which are aggregates of chromite and gangue minerals, most commonly magnesian silicates. Most chrome ores now used are petrographically chromitites which is a rock, rather than an individual mineral term. The title of this chapter, following past usage, is meant in the broad sense. Chromite is the only primary commercial source of chromium. This book is intended to deal only with nonmetallic minerals and rocks. Chromite uses are both metallic (ferroalloys) and nonmetallic (refractories and chemicals), but any discussion of mineralogy, geology, and mining is common for all types. A number of the major commercial ores are interchangeable, and their uses are determined by economic considerations. Mineralogy COMPOSITION [Chromite is a term embracing a wide range of chromium-bearing spinel*-group minerals the compositions of which can be expressed as (Mg,Fe2+)0.(Cr,AI,Fe3+ )203.t This can be further generalized to R2+O.R23+03 and the molecular RO: R,03 ratio is generally close to one. The exact composition may be arbitrarily expressed as a solid solution of six end-members, MgAI2O4, MgCr2O4, MgFe2O4 FeCr2O4, FeA12O4, and Fe2+.Fe23+04 with the proportions of each stated or plotted in the six-cornered prism of Johnston and Stevens61 or this scheme may be simplified to comprise only three endmembers making up a composition triangle, Fig 1. [ ] FIG 1-Triaxial composition diagram showing molecular compositions of chromites listed in Table 1. The RO.Fe2O3 corner includes Ti02 norms listed in the table. Note that the high-alumina chromites (1, 2, 3, 9), form a cluster well apart from the high-Cr2O3 chromites. There is a tendency for high-iron chromites to be higher in Fe2O3 + TiO2 but it is not a consistent or systematic relationship. The MgO/RO ratio must also be known to characterize the chromite chemically. Simplest and most convenient method is Thayer's' in which a chromite such as (Mg.65Fe.352+)O.(Cr.40Al.50Fe.103+)203 would be written as (Mge,) Cr eAlo. The molecular pro- portions of ferrous and ferric oxides can be seen at a glance as the divalent and trivalent oxides]

Jan 1, 1960

By J. D. Lindner, Gene E. Roark

Waterflooding operations in the Langston-Kleiner field. Young County, Tex., are described. Widespread application of formation fracturing has been practiced in both producing and injection wells. Field performance data arc cited which indicate than no detrimental effect on sweep efficiencies and that probable benefits in imectivily have resulted from the fracture treatments. I N T R O D U C I O N This paper is a report on a waterflood operation which is being carried out in the Lanpston-Kleiner field located in Young County, Tex. The oil reservoir aflected by this flood operation occurs in a Strawn sand member at an approximate depth of 3.550 ft subsurl'ace. The operators of' the project are Kleiner Estate. Turncr. Fiske. and West who are hereinafter collectively referred to as the Operators. Although the operation is unusual in several respects, the distinctive feature of this flood has been the widespread application of hydraulic formation fracturing treatments as a means to improve productivity and injectivity of the wells. It shall he the purpose of this paper to present basic information regarding the reservoir characteristics. op- craling practices, and waterflood behavior so that conclusions may be drawn concerning the effects which the fracture treatments have had on the performance of this water flood to datc. DEVELOP MENT Development of the 3,550 ft Strawn sand reservoir occurred during 1951 and 1952. The early development occurred on the Langston and Davis leases which arc in the northern region of the Operators' holdings and the wells were drilled on 20-acre proration units according to the field rules. However, studies of the economics of this program. coupled with the decision to proceed with pressure maintenance by water injection. resulted in the adoption of wider spacing in the later stages of development. This variation in spacing is apparent upon inspection of Fig. I upon which only the 3,550-ft Strawn sand producing and injection wells have been located on the Operators' properties. The development to the north of the operators leases is Ihe Garvey Strawn field and that to the south is the Taylor Strawn field. It wits determined that unitization of the leases to he involved in the waterflood program was not feasihle. Consequently. a system of offset injection wells, or lease line injection wells, was adopted from place to place as required to protect correlative rights in the program. This resulted in a dispersed array of injection and producing wells with relatively close proximity of wells along lease line areas and wider spacing toward

Jan 1, 1956

By R. S. Wagner, C. E. Miller, H. Brown

A dc field was applied to liquid BI-Sx or Au-Ge alloys of eutectic composition. The liquid alloys were kept at a temperature slightly above the eutectic. The concentration changes due to electrodijfusion are large enough to cause nuclcation and growth of the primary phases at the respective electrodes. Nearly complete separation of Bi-Sn eutectic was obtained as well as substantial separation of Au-Ge eutectic. The effect of an electric field on the solute distrihn-tion was itluestignted itt tlirectiortally solidified rods of a dilute Bi-Sn (0.5 al. pc,t Bi) alloy. Field-freezing was carried out in small-diameter cupillay tubes to avoid cotuectice mixing -of the liquid. The relative sollcte corzcentratioi, Cs/Co , was rneusred by n radioac1il.e tracer netlod. Cs/Co can be made both largev than unity or srialler than the equilibiuwz distvibrrlion c.oejyicienl, k, , oiler a substattiul portion of the soliclifi&apos;erl rocls. A direct current, passed through a liquid-metal solution, can cause substantial concentration changes by electrodiffusion. The magnitude of the change depends on the difference in ionic mobilities of the atomic species in solution. Electrodiffusion has been studied in many binary and ternary liquid alloys.&apos;y2 It was found that the rate of material transport decreases with time for a constant applied field, as a concentration gradient is established in the solution. A steady-state concentration profile is achieved when electro-diffusion is compensated by chemical diffusion. This may seem to limit the use of electrodif fusion for metallurgical application. However, a way of utilizing the effect of electrodiffusion is to combine it with crystallization or controlled freezing. rakin was first to propose this as a new method of separating metal alloys of eutectic composition at temperatures slightly above the eutectic temperature. It was possible by this method to separate Bi-Sn and Bi-Cd eutectics into their component phases. Angus et al discussed the possibility that the effective distribution coefficient, keff, could be varied by proper application of an electric field during solidification. The combination of electrodiffusion and solidification, called field-freezing, was discussed in detail by Pfann and aner. It was shown that field-freezing can be used as a crystal-growth process, an efficient method for eutectic separation, and a new means of changing the effective distribution coefficient. k,ff, beyond the usual range of ko < k,ff < 1. The liquid layer adjacent to the solid-liquid interface can be either increased or depleted in solute due to

Jan 1, 1967

By John Philip Zannaras

John Philip Zannaras (Registered Professional Engineer, Congress, Ariz.)- The authors show in their [Fig. 4] the cumulative results of grinding with two sizes of bails, one 30 mm and the other 20 mm. The Gaudin-Meloy probability for breakage for a single fall used by the authors in their paper is given by their [Eq. 6]. Another form of [Eq. 6] is given by Gaudin-Meloy in their paper as follows: [ ] From the definition of A given by Gaudin-Meloy it is obvious that A30 is greater than A., it therefore follows from the foregoing equation that according to the Gaudin-Meloy formula the probability of breakage for a single fall of all the balls in the 20-mm experiment was more than 2.25 times the probability of breakage in a single fall of all the 30-mm balls which is contradicted by the authors&apos; experimental evidence in [Fig. 4] in which is shown that much more grinding took place with the 30-mm balls. In fact the authors present convincing evidence that the Gaudin-Meloy work is erroneous because their work is based only on a geometric configuration and on ambiguous and uncertain definition of A and disregards the fact that the distribution of fracture depends on other important and indispensable factors including the intensity of stress caused on the feed grain by the balls. That there is an immense and chaotic variation of stresses caused on the feed grains by the balls is shown by a formula, derived by this writer and published in 1955. The derivation of this formula is given in the Appendix of this discussion; it contains the variables in the operation of ball mills and is based on the science of mechanics-not on probabilities. [ ] where T is the unit stress in pounds per square inch produced by the moving load, h is the height in feet through which P has fallen, E is the modulus of elasticity of the rock, P is weight of one ball, and L is the size of the grain (assumed to be a cube of side L). It will be shown by this writer&apos;s formula that when a 30-mm ball strikes any size of feed grain it will cause 1.837 times higher stress than the 20-mm ball when striking the same size grain. It will be shown that when the 30-mm ball or the 20-mm ball strikes a feed grain of 0.1 mm it will cause 90 times more stress on the grain than when it strikes a 2-mm grain.

Jan 1, 1974