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By J. B. Wagstaff, R. A. Buchanan, J. F. Elliott

High speed photography through blast-furnace tuyeres showed coke particles moving rapidly. Model studies showed a raceway was formed and gave quantitative results which were correlated with actual blast furnaces. Another study showed the similarity between hanging and the flooding of a packed column. This was explored by models. THE combustion zone before the tuyere in an iron blast furnace is a vital region because here are generated: 1—most of the gases on which the furnace depends to carry out its basic operation of reducing iron ore to the metallic state, and 2—the major fraction of the heat required in the nearby regions of the furnace for the various reduction reactions, the fusion of the slag, and the melting of the iron. Since the greater part of the coke is consumed in this region, the descent of the burden must be greatly affected by the characteristics of the tuyere zone. This region then would seem to be a profitable field for study. Fortunately, a view into this important zone is available to the operator through the tuyere peep sight. Here he sees relatively dark pieces of coke "dancing" in the blast. What he sees is of considerable help in interpreting the behavior of the furnace at a given time but the very rapidly moving particles and the intense radiation obscures what is happening very deep in the zone. This investigation was initiated in the hope that a better understanding of the combustion region could be obtained by using a high speed camera with a maximum speed of 3000 frames per sec. It seemed the best practical method of "slowing down" this characteristically violent action within the highly luminous field. Model studies and tuyere probing also have been used to aid in explaining the observed phenomena. Above the combustion zone, but below the fusion zone, there is probably a region in which the coke is comparatively stationary. Here are zones in which the gases must flow up through the granular bed counter to descending liquid slag and metal. There is no easy way to observe this zone in a blast furnace, but model studies have been of some help in explaining the nature of the zone and the laws governing the flow of the fluids involved. The whole problem is difficult and involved and any approach to a complete solution may require long investigation. This preliminary report has been written, therefore, because it is believed that appreciable progress has already been made that would be of interest to others. Tuyere Studies, Chemistry and Kinetics It is well known from the early work of Kinney and coworkers1,2 that combustion of carbon before the tuyeres appears to occur in two zones: Zone A: C + O, = CO2; AH77°F. = — 14,108 Btu per lb of carbon [I] Zone B: CO2 + C = 2CO; H77°F = + 6,183 Btu per lb of carbon [2] Zone A (Fig. 1) is close to the tip of the tuyere and zone B is somewhat farther back; there being a transition region in which both reactions occur. It is interesting to estimate the rate at which coke is burned before a tuyere with a wind rate of 90,000 cfm in a modern furnace having 18 tuyeres. Approximately 0.55 lb of carbon is consumed by eq 1 per tuyere per sec. A like amount disappears by eq 2 for a total consumption of 1.11 Ib per sec per tuyere. Assuming the coke is 85 pct C and has a bulk density of 30 lb per cu ft, this figure can be converted to a total of 1.30 lb of coke with a bulk volume of 0.043 cu ft disappearing per sec per tuyere. At the temperatures prevailing in the combustion zone (according to Kozlovich,³ he maximum is about 3400°F), the rate at which carbon is con-

Jan 1, 1953

By Garth M. Crosby, F. McIntosh Galbraith, Bronson Stringham

THE Hercules mine is located in the northeastern section of the Coeur d'Alene district, approximately 1 1/2 miles north of the town of Burke, Idaho. Surface indications of the ore deposit were first discovered in 1886, but regular mine production was not started until 1902 and was continuous until April 1925, when the known ore had been extracted. Incomplete records show that from 1912 until operations were suspended the mine produced 2 1/2 million tons of ore containing 9.4 pct lead and 7.7 oz of silver per ton, together with an estimated 2 pct zinc, 0.3 pct copper, and 20 pct iron. This operation was the first in a series of mining enterprises culminating in October 1947 with the consolidation of Day Mines, Inc. In the same year it was decided to unwater the levels below the collar of the Hercules shaft in the hope of finding some indication of a recurrence of ore. The unwatering operation has been described in a previous paper.1 The initial exploration, following recapture of the workings, showed sufficient promise to warrant a detailed study of the mineralogy with modern techniques.

Jan 12, 1953

By Heinrich Siemes, Christa Hennig-Michaeli

The effect of temperature and orientation on the plastic behaviour of an impure titaniferous magnetite from Palabora (South Africa) has been investigated. Prismatic specimens were axially compressed along [001], [110] and [111]. The strain rate was about 3.10-6 s-1. Trace analyses of glide lines revealed a plastic anisotropy due to glide on several non-equivalent crystallographic planes. At 200 °C {111}<112> twinning, {111}<110> slip and {100}<011> slip have been operative. At 400 °C {111}<110> slip and {100}<011> slip are primary glide modes. {110}<110> slip seems to be a secondary glide mode in the [001] specimens at 400 °C. {III}<112> twin glide generates isolated sharp lamellae. {111}<110> slip produces smooth surface striae. {100}<011> slip is characterized by coarse and partially wavy slip bands. {I10}<110> slip displays faint remarkably equidistant glide lines. The critical resolved shear stresses (CRSS) decrease with rise of temperature. The CRSS ratio of slip on [100) to slip on {lll} increases from 1.1 at 200 °C to 1.4 at 400 °C giving rise to a distinct flow anisotropy of the magnetite at 400 °C.

Jan 1, 1982

By Maurice C. Fetzer, Charles R. Austin

It has long been known that plain high-carbon steels may be susceptible to graphiti-zation below the A1 critical, but no data have been available to indicate what factors cause and tend to inhibit graphite formation. Two recent publicationsl,2 have shown that the factors controlling graphitization below the A1 are different from those operating above the A1 inversion where commercial graphitization of malleable iron begins. Furthermore, for plain high-carbon steels graphitization below the critical point does not appear to be related to ordinary chemical analyses. Many years ago it was recorded3 that the rate of graphitization at subeutectoid temperature is not a maximum just below the A1 critical, but at some lower temperature, which Austin and Norris have shown to be about 670°C. Indeed, work done in our laboratory has demonstrated that it is impossible to spheroidize certain steels in the temperature range of 650° to 710°C. without the formation of considerable amounts of graphite. However, if the temperature is maintained just below the A1 (720°C.) these same steels may be completely sphe-roidized at constant temperature. In previous studiesl,2,4 on I per cent plain carbon steels graphitization was encountered during prolonged tempering. The limited number of steels studied did not provide sufficiellt data to permit adequate study of the factors controlling this graphitization. Accordingly, a limited statistical investigation was undertaken, utilizing 18 steels of similar chemical analyses, furnished by four steel companies, who also supplied information regarding the history of manufacture. An extensive program of research is being carried out on these steels, including the effect of pretreatment and atmosphere on the nature and extent of graphitization, and the possible correlation of graphitization with such characteristic properties as hardenability, grain size and mechanical behavior. In the present paper discussion is restricted to a study of the correlation between graphitizing tendency at 670°C. after quenching from several temperatures above the critical, and (I) the minor variations in the chemistry of these steels of "similar" chemical composition, and (2) the deoxida-tion practice employed. The state of the lead bath, oxidized or protected from oxidation by charcoal, used in the tempering treatments is also considered. Materials Eighteen plain carbon steels of about I per cent carbon, and containing similar amounts of each of the other common elements usually found as impurities, were obtained in the form of rods % in, in diameter from four steel manufacturers. The analyses for ordinary and special elements of all the steels were made on the rod stock as received in the laboratory, and the re-

Jan 1, 1941

By Maurice C. Fetzer, Charles R. Austin

It has long been known that plain high-carbon steels may be susceptible to graphiti-zation below the A1 critical, but no data have been available to indicate what factors cause and tend to inhibit graphite formation. Two recent publicationsl,2 have shown that the factors controlling graphitization below the A1 are different from those operating above the A1 inversion where commercial graphitization of malleable iron begins. Furthermore, for plain high-carbon steels graphitization below the critical point does not appear to be related to ordinary chemical analyses. Many years ago it was recorded3 that the rate of graphitization at subeutectoid temperature is not a maximum just below the A1 critical, but at some lower temperature, which Austin and Norris have shown to be about 670°C. Indeed, work done in our laboratory has demonstrated that it is impossible to spheroidize certain steels in the temperature range of 650° to 710°C. without the formation of considerable amounts of graphite. However, if the temperature is maintained just below the A1 (720°C.) these same steels may be completely sphe-roidized at constant temperature. In previous studiesl,2,4 on I per cent plain carbon steels graphitization was encountered during prolonged tempering. The limited number of steels studied did not provide sufficiellt data to permit adequate study of the factors controlling this graphitization. Accordingly, a limited statistical investigation was undertaken, utilizing 18 steels of similar chemical analyses, furnished by four steel companies, who also supplied information regarding the history of manufacture. An extensive program of research is being carried out on these steels, including the effect of pretreatment and atmosphere on the nature and extent of graphitization, and the possible correlation of graphitization with such characteristic properties as hardenability, grain size and mechanical behavior. In the present paper discussion is restricted to a study of the correlation between graphitizing tendency at 670°C. after quenching from several temperatures above the critical, and (I) the minor variations in the chemistry of these steels of "similar" chemical composition, and (2) the deoxida-tion practice employed. The state of the lead bath, oxidized or protected from oxidation by charcoal, used in the tempering treatments is also considered. Materials Eighteen plain carbon steels of about I per cent carbon, and containing similar amounts of each of the other common elements usually found as impurities, were obtained in the form of rods % in, in diameter from four steel manufacturers. The analyses for ordinary and special elements of all the steels were made on the rod stock as received in the laboratory, and the re-

Jan 1, 1941

By R. E. Hoffman, R. A. Ward

The self-diffusion coefficient in high purity nickel has been measured over the temperature range 870&apos; to 1248°C. The results are described by the relation D = 1.27 exp[—-66,800/RT 1cm2ec-1. The measured activation energy correlates satisfactorily with absolute melting point, heat of fusion, and heat of sublimation. KNOWING the rates of self-diffusion is important in the understanding of many metallurgical reactions. However, in spite of the rather widespread interest in nickel, both commercially and in fundamental investigations, no measurement of the self-diffusion in solid nickel has previously been re- ported." In connection with a program of measuring rates of diffusion in some nickel alloys, self-diffusion in pure nickel has been investigated over a rather wide temperature range by combining a sectioning technique and a surface counting technique.

Jan 1, 1957

By A. L. Field

A. W. FAHRENWALD, Socorro, &apos;N. M. (communication to the Secretary*).-When asked to discuss Mr. Feild&apos;s paper, I felt most highly complimented to have the privilege of commenting on such a worthy and needed piece of apparatus. In consideration of the importance of the viscosity of blast-furnace slags and the relation existing between the&apos; melting point of a slag and its viscosity, the introduction of this apparatus should be a welcome means or assistant in the study of the physical properties of a slag. Up to the present time, it is A fact that this side of the practical working of the blast furnace has been sadly neglected by those investigating slags. It is easily seen that the fluidity of a slag is of as great importance as its melting point. It is not necessarily true that a slag having a low melting point will have a correspondingly low viscosity or be highly fluid. For example, a slag having a melting point of 1,100° C. may have to be superheated to, say,1,300° C., in order to have as high a fluidity as another slag whose melting point is, say, 1,250° C. The latter in this case would be the more economical. This point has been brought out very nicely by Mr. Feild. Before discussing this paper further, I think it will be well to outline some of the points, a discussion of which may be in order:

Jan 3, 1917

By Edwin H. Olson, Morton Smutz, Charles J. Baroch

IN 1949 an orebody containing some 10 billion lb of recoverable rare earth metals was discovered in the Mountain Pass district of San Bernardino County, California.1 The following year Molybdenum Corp. of America purchased a number of claims at the deposit and a mill on the property which had been constructed to process the district&apos;s gold ores. Average composition of ore from the San Bernardino deposit is less than 0.1 pct ThO2, 25 to 35 pet calcite, 10 pet rare earth oxides, 15 to 20 pet silica, and 30 to 40 pet barite.2 Rare earth content of the ore analyzes 50.7 pet CeO2, 4.2 pet Pr6O11, 11.7 pet Nd2O3, 1.3 pet Sm2O3, and 34.3 pet La2O3, and others.2

Jan 3, 1959

By B. C. Allen

Grain boundary grooving has been studied in chromium, molybdenum, and tungsten under a variety of conditions using high vacuum techniques and tantalum -gettered argon. The average surface free energy of solid chromium, and the chromium-liquid silver interface free energy were respectively found to be 2200 ± 250 and 500 i 130 ergs per sq cm from groove formation kinetics and estimates of pertinent volume difffusion coefficients. The results for chromium were unffected by variations in interstitial content ranging from 0.003 to 0.09 pct C, or 0.003 to 0.03 pct O. Surface diffusion is the primary mechanism of groove formation in chromium under 1 atm argon at 1200" to 140O°C, and is essentially unaffected by 0.003 to 0.09 pct C, 0.003 to 0.03 pct O , metastable nitrogen contents up to -0.01 pct, and up to 2 torr Ag vapor. At higher temperatures, the major mechanism is volume diffusion in argon or evaporation-condensation in stutic vacuum. Surface diffusion occurs in molybdenum at 0.5 to 0.96 and in tungsten at 0.5 to 0.9 of the absolute melting tempera -ture by a single mechanism, possibly by the migration of single adatoms or vacancies. Results were slightly affected by up to 23 tory Sn vapor, and in molybdenum were essentially unaffected by 0.5 Ti or carbon in the range 0.002 to 0.02 pct. Volume difffusion through the liquid is the mechanism of groove formation in chromium-liquid silver at 1200" to 1400°C and in molybdenum-, Mo-0.5Ti-, and tungsten-liquid tin at 1200" to 2000°C. The solid-liquid interface free energies involved were estimated from grooving kanetics. WHEN a grain boundary intersects a solid surface, a groove tends to form along the line of intersection at temperatures above about half the absolute melting point (0.5 TM). The groove progressively grows by preferential atomic migration either by diffusion or evaporation. Establishment of a groove angle occurs in accordance with the grain boundary and surface free energies involved. The motivation for groove formation is a reduction in the total surface free energy of the system. This study is a continuation of previous work on thermal grooving of chromium, molybdenum, and tungsten.&apos; The temperature ranges were extended, and the effect of metallic and interstitial impurities was evaluated. The results were such that certain interface free energies and surface self-diffusion coefficients were deduced from the grooving kinetics. EXPERIMENTAL WORK Materials and Preparation. As indicated in Table I, the 0.05-0.08-cm-thick chromium, molybdenum, and tungsten sheet used was nominally 99.99 pct after recrystallization. Two lots of molybdenum with about the same analysis, Mo-0.5Ti,* and tungsten were ob- *Alloy compsitions are expressed in weight percent . tained commercially. Extruded chromium rod,&apos; prepared from iodide process crystals, was warm rolled to sheet at 700°C. Sheet of three Cr-0 impurity alloys containing up to 0.03 pct 0 was prepared by warm rolling arc melted, extruded, and swaged rod. Two Cr-C impurity alloys containing up to 0.09 pct C were made by equilibrating unalloyed chromium with a known amount of CH4 for 24 hr at 1150°C in previously evacuated quartz capsules. Chromium containing nominally 0.015 and 0.06 pct N was similarly prepared by equilibration with NH3. The sheet was recrystallized to give a stable grain size about equal to the sheet thickness. Molybdenum and Mo-O.5Ti were recrystallized in a tantalum resistance furnace 1 hr at 1 x lo-5 torr at 2300" and 220O°C, respectively. Tungsten was similarly annealed for 1 hr at 2500°C. Chromium and its impurity alloys were outgassed at 1100°C and recrystallized 1 hr at 1700°C under 1 atm Ar. Except for nitrogen, the impurity content stayed roughly constant. Nitrogen in both alloys was reduced to <0.001 pct. In fact, over 80 pct of the added nitrogen was lost after outgassing at llOO°C and annealing sheet 1 hr at 1300°C in argon in the presence of tantalum. Such a rapid loss can be rationalized since -2 torr N are required for equilibrium with 0.04 pct N in solution,3 while the equilibrium pressure is ~10-5 torr over tantalum at 1300°C.4 The recrystallized sheet was cut into small coupons which were metallographically ground and polished on one side with a minimum of grain boundary relief. The surface roughness was on the order of 0.01 µ. The tin and silver used were nominally 99.999 spec-trographically pure. After being outgassed at 1100°C and equilibrated in a molybdenum crucible for 0.5 hr at 1800°C in argon, the tin contained 3 ppm 0, <0.3 ppm N, and 0.1 ppm H. Following outgassing at 900°C and equilibration in a chromium crucible 1 hr at 1400°C in argon, the gas content of the silver was 1 ppm O, <0.5 ppm N, and 0.3 ppm H. Grooving Under Argon or Vacuum. All specimens were placed in unsealed containers made from rod or sheet of the same alloy, thereby enabling the polished surface to achieve gas-solid equilibrium. The annealing fixtures are shown in Fig. 1. The specimen was placed in a resistance furnace with a tantalum or Ta-10W heating element plus tantalum fixtures or radiation shields. Chromium was outgassed at 1100°C, and molybdenum and tungsten were outgassed at 1900°C to 1 x l0-5 torr or at the grooving temperature, whichever was lower. In vacuum anneals, the specimen was then heated directly to the intended grooving temperature. In argon anneals, 99.996 Ar was admitted

Jan 1, 1970

By V. R. Garfias, R. V. Whetsel, J. W. Ristori

Preliminary estimates indicate that world consumption of petroleum and related fuels in 1938 will be close to 1,908,000,000 bbl., or approximately 7,000,000 bbl. less than in 1937. This total does not include military consumption in foreign countries, which for obvious reasons is not made public. Foreign military consumption in any one year, however, is approximately represented by the difference between the total production of petroleum and related fuels and the "partial total" consumption above noted, after adding any decrease, or subtracting any increase in stocks in the United States. Fig. 1 illustrates this "difference" and shows that in 1937 and 1938, owing to the wars in China and Spain and the possibility of armed conflict in Central Europe, foreign military consumption—and possibly additions to foreign stocks—increased nearly 70,000,000 bbl. in 1937 over 1936 and remained at this high rate throughout 1938. No official information on foreign oil stocks is available to the writers. Table 1, recently published, purports to give the oil in storage in some of the European countries, but it is not known whether the figures include oil stocks for military purposes. It should be noted that with the annexation by Germany of Austria and part of Czechoslovakia the consumption of the country has increased to 53,000,000 bbl., which is about 36,000,000 short of the German produc-

Jan 1, 1939

By J. W. Ristori, R. V. Whetsel, V. R. Garfias

Preliminary estimates indicate that world consumption of petroleum and related fuels in 1938 will be close to 1,908,000,000 bbl., or approximately 7,000,000 bbl. less than in 1937. This total does not include military consumption in foreign countries, which for obvious reasons is not made public. Foreign military consumption in any one year, however, is approximately represented by the difference between the total production of petroleum and related fuels and the "partial total" consumption above noted, after adding any decrease, or subtracting any increase in stocks in the United States. Fig. 1 illustrates this "difference" and shows that in 1937 and 1938, owing to the wars in China and Spain and the possibility of armed conflict in Central Europe, foreign military consumption—and possibly additions to foreign stocks—increased nearly 70,000,000 bbl. in 1937 over 1936 and remained at this high rate throughout 1938. No official information on foreign oil stocks is available to the writers. Table 1, recently published, purports to give the oil in storage in some of the European countries, but it is not known whether the figures include oil stocks for military purposes. It should be noted that with the annexation by Germany of Austria and part of Czechoslovakia the consumption of the country has increased to 53,000,000 bbl., which is about 36,000,000 short of the German produc-

Jan 1, 1939

By R. W. Smith, M. E. Brookes

The temperature at which th: quenched 0&apos; (ordered bcc) phase transfo.rms to the ( (complex hexagonal) phase on heating has been examined for certain Ag-Zn and Ag-Au-Zn alloys using an electrical resistivity method. The transition temperature decreases by approxinzately 7°C as the zinc content is reduced by 1 at. pct. The critical temperature, Tc, for long-range order has also been measured for a number of Ag-Au-Zn alloys. Extrapolation to zero gold content suggests that Tc decreases by approximately 5°C per 1 at. pct reduction in zinc content. The 0 phase of the Ag-Zn system exists over a narrow range near the composition Ag zn,&apos; Fig. 1, and has a bcc structure which is disordered above 272°C. Slow cooling to temperatures below the range 274"/258"C allows the complex hexagonal phase, r° to form.2 This is the stable structure at room temperature.3 Upon quenching 0 -phase alloys from high temperatures, it is found that the 0 — (&apos; transformation is suppressed; but ordering takes place (i.e., 0 -0&apos;). This ordered structure can also be obtained by the room-temperature aging of cold-worked (0.4 Deformation of the 0&apos; phase gives rise to a fur- ther hexagonal phase ( (of nearly ideal axial ratio) which reverts to b&apos; within a few hours.= In view of this, it has been suggested that the equilibrium struc-

Jan 1, 1969

By C. S. Yust, J. W. Smith, J. R. Walsh, R. E. Simpson

This paper presents the results of a complete reservoir studv designed to determine a sound economic program for the conservation of oil and gas in the Pickton field, Hopkins County, Texas. The Pickton field produces from the Bacon Lime with all indications of the study being that production is predominately by dissolved-gas drive. Calculations of the total ultimate recovery to be expected under primary operations indicated only 16.7 per cent of the oil originally in place would be recovered. This unusually low recovery is due to the type of drive operating and the extremely high dissolved gas-oil ratio and shrinkage. Results are presented for six plans of returning gas to the reservoir, evaluated to determine (1) comparative recoveries and economics of (a) returning gas at a constant rate by supplementing Pickton gas with extraneous gas during the early portion of the operation, and (b) conventional gas-return operations without using extraneous gas, and (2) the optimum size of compressor plant for each type of pressure maintenance. The over-all economic program considers, for either type pressure maintenance operation. a gasoline plant to process the unusually rich casinghead gas. Since pressure maintenance will disturb equities, pooling of royalties is in the case of Pickton a prerequisite to conservation of oil by this type of operation, both from an economic and legal standpoint. In the event pooling of royalties cannot be achieved, the study considers a gasoline plant to operate under a modified primary production operation which will make the conservation of gas possible. INTRODUCTION The Pickton field, located in Hopkins County, Texas. was discovered in November, 1944. by the completion of Humble&apos;s C. D. Nichols 1, in the Bacon lime of the Lower Glen Rose formation, through perforations from 7,888 to 7.896 feet. The well initially produced 50.2 API gravity oil with a gas-oil ratio of 1,350 cubic feet per barrel. Subsurface samples of the reservoir fluid obtained soon after completion of the discovery well showed that the Pickton crude is unique in that it has an extremely high dissolved gas-oil ratio and is subject to very severe shrinkage. Calculations of the future behavior of the Pickton reservoir indicated that ultimate oil recovery by primary operations would be 3,269,000 barrels, representing only 16.7 per cent of the oil in place (19,577,000 stock-tank barrels), and that recovery could be substantially increased by returning the produced gas. The cumulative production of 1,382,694 barrels on November 1: 1947, amounted to 42.3 per cent of the estimated ultimate oil recovery from primary operations. The purpose of this study is to determine and evaluate the optimum program for conservation of oil and gas in the Pick-ton field, including the desirability of conducting gas-return operations and of installing a gasoline plant. LOCATION AND DESCRIPTION Pickton Field, The Pickton field, as shown in Fig. 1, is located in southwest Hopkins County, Texas, 12.5 miles southwest of the New Hope field, 2.7 miles northeast of the Coke field, 16 miles southwest of Sulphur Springs, and 8 miles northwest of Winnsboro, Texas.

Jan 1, 1949

By C. S. Yust, J. W. Smith, J. R. Walsh, R. E. Simpson

This paper presents the results of a complete reservoir studv designed to determine a sound economic program for the conservation of oil and gas in the Pickton field, Hopkins County, Texas. The Pickton field produces from the Bacon Lime with all indications of the study being that production is predominately by dissolved-gas drive. Calculations of the total ultimate recovery to be expected under primary operations indicated only 16.7 per cent of the oil originally in place would be recovered. This unusually low recovery is due to the type of drive operating and the extremely high dissolved gas-oil ratio and shrinkage. Results are presented for six plans of returning gas to the reservoir, evaluated to determine (1) comparative recoveries and economics of (a) returning gas at a constant rate by supplementing Pickton gas with extraneous gas during the early portion of the operation, and (b) conventional gas-return operations without using extraneous gas, and (2) the optimum size of compressor plant for each type of pressure maintenance. The over-all economic program considers, for either type pressure maintenance operation. a gasoline plant to process the unusually rich casinghead gas. Since pressure maintenance will disturb equities, pooling of royalties is in the case of Pickton a prerequisite to conservation of oil by this type of operation, both from an economic and legal standpoint. In the event pooling of royalties cannot be achieved, the study considers a gasoline plant to operate under a modified primary production operation which will make the conservation of gas possible. INTRODUCTION The Pickton field, located in Hopkins County, Texas. was discovered in November, 1944. by the completion of Humble&apos;s C. D. Nichols 1, in the Bacon lime of the Lower Glen Rose formation, through perforations from 7,888 to 7.896 feet. The well initially produced 50.2 API gravity oil with a gas-oil ratio of 1,350 cubic feet per barrel. Subsurface samples of the reservoir fluid obtained soon after completion of the discovery well showed that the Pickton crude is unique in that it has an extremely high dissolved gas-oil ratio and is subject to very severe shrinkage. Calculations of the future behavior of the Pickton reservoir indicated that ultimate oil recovery by primary operations would be 3,269,000 barrels, representing only 16.7 per cent of the oil in place (19,577,000 stock-tank barrels), and that recovery could be substantially increased by returning the produced gas. The cumulative production of 1,382,694 barrels on November 1: 1947, amounted to 42.3 per cent of the estimated ultimate oil recovery from primary operations. The purpose of this study is to determine and evaluate the optimum program for conservation of oil and gas in the Pick-ton field, including the desirability of conducting gas-return operations and of installing a gasoline plant. LOCATION AND DESCRIPTION Pickton Field, The Pickton field, as shown in Fig. 1, is located in southwest Hopkins County, Texas, 12.5 miles southwest of the New Hope field, 2.7 miles northeast of the Coke field, 16 miles southwest of Sulphur Springs, and 8 miles northwest of Winnsboro, Texas.

Jan 1, 1949

By A. H. Heim

A method and apparatus for measuring gas porosities of rocks are described. The apparatus can be assembled from commercially available components. In principle, measurements are made by volume substitution at constant pressure. The maximum error is not more than 0.3 porosity per cent. Typical results are given. INTRODUCTION Determining the porosity of rock samples is one of the most important and yet most varied types of measurement in core analysis. Among the many techniques devised are the so-called "gas porosity" methods. An old and well known example is the Washburn-Bunting method.&apos; The U. S. Bureau of Mines2-&apos; described and later improved the apparatus for a now widely used method generally known as the "Boyle&apos;s law" method. In the present form of the Washburn-Bunting method,&apos; the volume of air in the pores of a rock sample at atmospheric pressure is extracted and then collected in a graduated burette at atmospheric pressure. The volume of air is read directly as the pore volume of the sample. The absolute error in reading the collected volume of gas is independent of the total volume; thus, the relative error is larger when the volume is small, as it is for rocks of low porosity. In addition, the sample after measurement contains mercury, which limits its use for other analyses. The Bureau of Mines (or Boyle&apos;s law) method measures directly the solids volume of a sample from which the pore volume and porosity are derived, using a separate measurement of the bulk volume. Gas at a few atmospheres pressure is introduced into a sample chamber of known volume containing the rock sample. The pressure is accurately measured. Following, the gas is expanded into a burette at 1 atm, and the gas volume is read directly. From the initial pressure p, and the final pressure p2 and volume v,, the initial gas volume v1 is calculated using Boyle&apos;s law; that is, p1v1 = p2v2. Volume v, minus the volume of the empty sample chamber is the solids volume of the sample. The accuracy of the method is limited, unless corrections are made, by deviations of the gas from the "ideal" gas-law behavior assumed in the simple form of Boyle&apos;s law. The purpose of the present paper is to describe a method for measuring the gas porosity of a rock which avoids many of these difficulties. Gas volumes are measured directly with the same accuracy as the bulk volumes. Pressures of at least an order of magnitude larger than those of previous methods are employed to insure rapid penetration of the gas into the sample. While special equipment may be built to apply the method, the porosimeter may be constructed as well from commercially available components. For simplicity, the apparatus described will be referred to as the "Constant-Pressure gas porosimeter". THE CONSTANT-PRESSURE METHOD Fig. 1 shows schematically the arrangement of components comprising the present Constant-Pressure porosimeter. Briefly, the method is one of volume substitution and may be considered a null measurement. Omitting (for the present) some of the operational details, the method of measurement consists of the following three steps. 1. After evacuation, the volume of the measuring system (a ballast chamber, a manifold, two gauges and their connections) up to the sample chamber is filled with gas to a high pressure (- 1,000 psi). A sample of the gas at this pressure is trapped in one side of a sensitive differential pressure gauge to serve as the reference pressure for subsequent steps. 2. The evacuated sample chamber containing the rock sample is opened to the measuring system. As the gas expands into the chamber, the resulting decrease in pressure unbalances the differential pressure gauge. 3. The pressure is restored by means of a mercury volumetric pump. The volume of mercury injected exactly equals the free or void volume of the sample chamber (volume of empty chamber minus the solids volume of the rock within). From the injected volume and the known empty chamber volume, the solids volume is obtained and the porosity calculated. The pressure and the volume occupied by the gas are the same before and after opening the sample chamber. Expansion and compression of the gas are incidental operations and do not enter into the calculation of porosity. By the pressure balancing or nulling, the free volume of the sample chamber is merely substituted by an equal and measured volume of mercury. Since the measurements are at constant pressure, there are no compressibility corrections necessary for the sample chamber.

By E. J. Roberts

The theory is developed that the tons ground through a given mesh per day in a wet ball mill is proportional to the percent plus that mesh in contact with the balls and the net power applied to the balls at this point. A grindability test is described. DURING the course of a study of the fundamentals of classification in 1937, the need for a more basic understanding of the action of a ball mill became acute. Unless one knows how classification affects grinding, one cannot hope to effectively improve on classification. The methods of evaluating grinding efficiency that depend on surface developed were studied but soon discarded for two reasons: 1. There was no apparent method which could be generally used to give a reliable figure for the actual new surface developed as a result of grinding. Subsequent papers have not changed this conclusion. 2. The practical evaluation of grinding in the main ore dressing applications was in terms of the percentage retained on a screen which passes 90 to 99 pct of the material and not in terms of surface area. The Probability Theory With the background of our experience in the field of closed-circuit grinding, together with the papers of Lennox,1 Gow,2 Gaudin,8 Fahrenwald,4 Coghill, and others, the approach of the theoretical physicist was then tried. The thought was somewhat as follows: When one grinds in a ball mill, a given expenditure of power leads either to a certain number of point to point blows per hp-hr or to a certain distance of line contact per hp-hr, depending on whether the action of the balls is considered to be cascading or rolling. It is also assumed that the balls actually come together on each blow or during the roll. Then a volume of slurry will be covered per minute which is some function of the size of the particle being considered (see fig. 1). All particles coarser than this size will be reduced through this size. This volume of slurry contains a certain weight of ore, depending on the percent solids and the density of the solids. If we fix the percent solids and the density of the solids and let w be this certain weight of ore in the volume covered, then, in mathematical terms, what we have just postulated is, w —— 8 hp (a) dt If W is the total weight of ore present in the mill, then we can write. W w/8 hp (b) W dt and if C is the cumulative percent plus the size chosen at the start of the time interval dt, w w c/dt W 8 hp x c (c) wc But wc/100 is the weight plus the size chosen which at 100 wc the close of time dt is finer than that size, and W is the decrease in the percent plus of the whole mass of ore or —dC. Then, —W dC/dt 8 hp x C. (d) In other words, the mesh tons ground through a given size per unit of time is proportional to the hp and the percent plus the mesh. A crude analogy would be to picture a 1-ft-wide steam roller going down the road at 1 ft per sec. If we place one egg on the road per square foot, one egg will be smashed per second. If we place a dozen eggs per square foot, a dozen eggs will be crushed per second. Similarly, if all the particles in w are plus the mesh, i.e., C=100, we should have a maximum rate of reduction. If only 10 pct of them are plus the mesh (C=10), we would have only one tenth the maximum rate; if only 1 pct are plus the mesh, the balls have a hard time finding anything to work on. This is where the term "probability theory" comes from. The chances of the balls crushing a particle through a given mesh depends directly on the concentration of particles coarser than this mesh in the general pulp in the mill. Giving W the units of tons and dividing equation (d) through by W, we obtain -dC hp ----- = k---— C [1] dt ton where k is a constant for any one size of particle, density of solid and moisture content of pulp. Eq 1 is the rate equation for a first order reaction and says that the rate of decrease of the percent plus a given mesh with time is directly proportional to the hp per ton applied to the body of ore and to the percent plus the mesh in the ore mass as a whole. Since it is a differential equation, it only

Jan 1, 1951

By E. J. Roberts

The theory is developed that the tons ground through a given mesh per day in a wet ball mill is proportional to the percent plus that mesh in contact with the balls and the net power applied to the balls at this point. A grindability test is described. DURING the course of a study of the fundamentals of classification in 1937, the need for a more basic understanding of the action of a ball mill became acute. Unless one knows how classification affects grinding, one cannot hope to effectively improve on classification. The methods of evaluating grinding efficiency that depend on surface developed were studied but soon discarded for two reasons: 1. There was no apparent method which could be generally used to give a reliable figure for the actual new surface developed as a result of grinding. Subsequent papers have not changed this conclusion. 2. The practical evaluation of grinding in the main ore dressing applications was in terms of the percentage retained on a screen which passes 90 to 99 pct of the material and not in terms of surface area. The Probability Theory With the background of our experience in the field of closed-circuit grinding, together with the papers of Lennox,1 Gow,2 Gaudin,8 Fahrenwald,4 Coghill, and others, the approach of the theoretical physicist was then tried. The thought was somewhat as follows: When one grinds in a ball mill, a given expenditure of power leads either to a certain number of point to point blows per hp-hr or to a certain distance of line contact per hp-hr, depending on whether the action of the balls is considered to be cascading or rolling. It is also assumed that the balls actually come together on each blow or during the roll. Then a volume of slurry will be covered per minute which is some function of the size of the particle being considered (see fig. 1). All particles coarser than this size will be reduced through this size. This volume of slurry contains a certain weight of ore, depending on the percent solids and the density of the solids. If we fix the percent solids and the density of the solids and let w be this certain weight of ore in the volume covered, then, in mathematical terms, what we have just postulated is, w —— 8 hp (a) dt If W is the total weight of ore present in the mill, then we can write. W w/8 hp (b) W dt and if C is the cumulative percent plus the size chosen at the start of the time interval dt, w w c/dt W 8 hp x c (c) wc But wc/100 is the weight plus the size chosen which at 100 wc the close of time dt is finer than that size, and W is the decrease in the percent plus of the whole mass of ore or —dC. Then, —W dC/dt 8 hp x C. (d) In other words, the mesh tons ground through a given size per unit of time is proportional to the hp and the percent plus the mesh. A crude analogy would be to picture a 1-ft-wide steam roller going down the road at 1 ft per sec. If we place one egg on the road per square foot, one egg will be smashed per second. If we place a dozen eggs per square foot, a dozen eggs will be crushed per second. Similarly, if all the particles in w are plus the mesh, i.e., C=100, we should have a maximum rate of reduction. If only 10 pct of them are plus the mesh (C=10), we would have only one tenth the maximum rate; if only 1 pct are plus the mesh, the balls have a hard time finding anything to work on. This is where the term "probability theory" comes from. The chances of the balls crushing a particle through a given mesh depends directly on the concentration of particles coarser than this mesh in the general pulp in the mill. Giving W the units of tons and dividing equation (d) through by W, we obtain -dC hp ----- = k---— C [1] dt ton where k is a constant for any one size of particle, density of solid and moisture content of pulp. Eq 1 is the rate equation for a first order reaction and says that the rate of decrease of the percent plus a given mesh with time is directly proportional to the hp per ton applied to the body of ore and to the percent plus the mesh in the ore mass as a whole. Since it is a differential equation, it only

Jan 1, 1951

By T. J. Koppenaal

The surface slip line structure has been investigated by optical microscopy during the easy glide deformation of Cu-A1 single crystals as a function of composition, testing temperature and prior thermal treatment. The slip line structure in alloys of 2.5 or less at. pct Al is similar to pure copper, while alloys of 5 or more at. pct Al show slip tracings typical of a brass. Cross slip is observed in the "a-brass type" crystals and the amount of this type of slip increases rapidly with aluminum content. The cross slip tendency in 14 at. pct Al crystals is signicantly higher when tested at 150°C as compared to 4.2" and 77°K. In addition, cross slip is more pronounced in this alloy in the furnace cooled condition than when quenched from 450°C. The cross slip behavior is analyzed in terms of existing models for this type of deformation. In two previous investigations, reports of yield points1 and solid solution strengthening2 in Cu-A1 single crystals have been given. This paper enlarges upon the brief description of the slip line structure discussed in these reports. Since the easy glide slip line pattern of copper changes markedly with the addition of -30 pct Zn (-brass),3 a study of slip lines as a function of solute additions in Cu solid solutions should help to explain some of these differences. In addition to composition variables, slip lines have also been studied as a function of testing temperature and prior thermal treatment. PROCEDURE The slip line observations were made on single crystals of 0.5 to 14 at. pct Al using a light microscope. Details concerning the preparation and basic testing procedure are given elsewhere.&apos; Prior to testing, each crystal was homogenized at 900°C for 24 hrs, furnace cooled, and electrolytically polished in a 60 pct phosphoric acid solution. The strain rate was-5 X 10 sec-I in each case. Unless otherwise stated, all observations reported upon here were made during the early stages of easy glide. RESULTS AND DISCUSSION The maximum magnification generally used was 1000X, and slip lines could be resolved down to about 105 cm (1000A). This resolution is appreciably less than obtainable with electron microscopy replica techniques where the replication can resolve slip lines down to about 40 A. Thus, while many qualitative features could be studied, the type of quantitative data obtainable with an electron microscopy replica study could not be made. Crystals containing 0.5 and 2.5 at. pct Al deform much like pure copper exhibiting a high density of fine slip lines that cover the entire gage length of the specimens. Fig. 1 shows the surface slip line pattern in a 2.5 at. pct A1 extended 0.01 shear strain at room temperature. Crystals having 5 to 14 at. pct A1 showed appreciably coarser slip lines that were generally concentrated at one end of the gage length. During easy glide these coarse slip lines propagate along the gage length in a manner similar to that observed in a-brass single crystals by Piercy, Cahn, and cottrel14 and refered to by them as a Lüders band propagation. Fig. 2 shows a typical area of these coarse slips in a 14 at. pct A1 crystal after a room temperature shear strain of 0.01. Two slip systems were apparently active. Using a method described by Cullity, the angles, between the specimen axis and the normals of the primary and secondary slip planes were determined to be 50 and 84 deg, respectively. &apos;From the Laue photograph, was 52, 81, 66, and 30 deg for the primary, cross, conjugate, and fourth slip planes, respectively. The secondary active plane in Fig. 2 is thus established as the cross slip plane, and the operative slip system is evidently the cross slip system, e.g., slip

Jan 1, 1963

By S. R. Maloof, W. R. Mitchell, J. A. Mullendore

Preliminary experimental evidence is presented to show that the metallic impurities aluminum, iron, and silicon, and beryllium oxide as found in commercially pure hot-pressed beryllium powder can be reduced to lower Concentrations by Zone -Purification techniques. The reduction in the concentration of aluminum to extremely low levels (10 PPm) is noteworthy, since earlier work demonstrated that aluminum is a major factor contributing to the hot-tearing of beryllium during fusion welding. On the basis of present findings, a method is suggested for producing beryllium metal of improved weldability. EXPERIMENTAL research now being conducted on the purification of beryllium indicates that several of the metallic impurities and beryllium oxide can be reduced to lower concentrations by employing standard horizontal zone-refining techniques. For the preliminary work, commercially-pure hot-pressed beryllium having a purity of 97.84 pct was used. The chemical composition is given in Table I. The hot-pressed beryllium was machined into bars 5/8 by 5/8 by 4 to 6 in. in length. Beryllium-oxide boats which had been conditioned by prior heating in a vacuum of 10"5 mm of Hg at 1100°C for 3 hr were used to hold the beryllium while it was zone melted. The boat with its charge, along with a smaller beryllium-oxide boat containing scrap beryllium to be used for gettering purposes, was loaded into a quartz tube and evacuated to 10-6 mm of Hg. Alter alternately evacuating and flushing three times with purified argon, the furnace tube was backfilled to a pressure of 1/6 atm of A and sealed off by means of a vacuum-tight stopcock. It was then removed from the pumping equipment and mounted on the traveling carriage of the zone-refining apparatus. Heating was accomplished with a 10 kw 450 kc induc- tion heating unit using an induction coil consisting of two turns of 3/16-in. diam copper tubing. Before starting to zone melt, the atmosphere in the furnace tube was gettered by heating the scrap beryllium in the smaller boat to above its melting point and holding at temperature for several minutes. The carriage was then shifted so as to locate one end of the beryllium ingot in the large boat within the induction coil. A molten zone approximately 3/4 to 1 in. was established by loading directly into the ingot. The molten zone was moved very slowly along the length of the ingot. Before each pass was made the procedure for evacuating, flushing, and backfilling, and so forth was repeatedI&apos; Speeds of 1 1/2 and 3 in- per hr were used with up to twelve zone passes. The appearance of a typical zone-refined ingot is shown in Fig. 1. After zone refining, the grains in the ingot appear to be elongated in the direction of zone travel, whilst before, they are essentially equi-axed. A microexamination revealed the presence of a network in the beryllium grains as seen in Fig. 2. Laue spots in back reflection pictures taken of the sample were not sharp, indicating the presence of subgrains in the structure. As can be seen, however, many of the network boundaries cross beryllium grain boundaries. It has been shown by Martin and Moore1 that beryllium solidifies as a bcc structure which then transforms to the hexagonal structure at about 1250oC.It is believed that the observed network is merely the outline of the bcc structure which formed from the melt and are not subgrain boundaries. In order to eliminate surface contaminants, approximately 1/16 of an inch of material was removed from the outer skin of each ingot after zone refining.

Jan 1, 1962

By E. R. Buchanan, R. E. Reed-Hill

Cylindrical magnesium single crystals were deformed in torsion. The axis of torsion was the basal pole. Five crystals were deformed to different strains between 0.08 and 1.03 and then sectioned in order to determine their dislocation densities using the transmission electron microscope. The work hardening rate of all specimens was at least an order of magnitude higher than that normally associated with easy glide in a tension test and comparable to that obserzed in stage B of a tension test. The correspondence between stage B in a tension test and the initial stages of a torsion test is believed to result from the fact that in both cases deformation occurs in a structure containing roughly equivalent densities of the dislocations associated with the three basal slip vectors. THERE are three basic ways of changing the shape of a crystal using slip dislocations. The crystal can be sheared along a slip direction in a slip plane; it can be bent about an axis in the slip plane normal to the slip direction; and, if the slip plane contains multiple slip directions, it can be twisted or rotated about the slip plane normal. Of the three processes, generally known as translational, flexural, and rotational slip, only rotational slip has not been extensively investigated. The object of the present research was to obtain basic information about this phase of crystalline plasticity. This paper is concerned with some aspects of the stress-strain curves obtained by twisting magnesium crystals about their basal poles. Magnesium was selected for four reasons. One, its recovery rate at room temperature is relatively low. Two, single crystals may be easily grown. Three, at room temperature the critical resolved shear stress for basal slip is about two orders of magnitude lower than that for nonbasal slip, so that rotational slip might be expected to occur primarily by basal slip. Finally, relationships between flow stress, shear strain, and dislocation density have been determined for tensile deformation of magnesium crystals,&apos; thereby providing a basis of comparison for the torsional results. EXPERIMENTAL PROCEDURES Crystals were grown from 0.5 in. diam extruded sublimed magnesium rod furnished by the Dow Chemical Co. who reported that it contained in weight percent less than 0.0003 Al, 0.01 Ca, 0.01 Cu, 0.0012 Fe, 0.001 Mn, 0.0005 Ni, 0.003 Pb, 0.001 Si, 0.01 Sn, and 0.02 Zn, with the balance magnesium. All crystals were grown in a dried argon atmosphere using Jill-son&apos;s2 modified Bridgman technique. Two different methods were used to obtain crystals with the basal plane normal to the specimen axis. These included direct growth from seeds of the proper orientation, and spark machining (trepanning) of 0.5 in. diam cylinders from larger (1.5 in. diam) randomly grown crystals. The crystals thus produced were polished in a 20 pct HC1 water solution and then etched in a 1 pct HC1 water solution to develop etch pits lying in rows parallel to the basal plane trace. The crystals were then revolved about their axes on the stage of a low-powered microscope. Torsion specimens were prepared only from those crystals whose axes were normal to the rows of etch pits. It is estimated that this simple orientation method was accurate to about 51 deg. 1.625 in. long cylinders were next cut from these selected crystals and then acid machined in a 20 pct HC1 water solution into torsion specimens with a 1 in. long by 0.30 in. diam reduced gage section. Following this, they were annealed in air at 400°C and furnace cooled to room temperature. The specimens were given a final polish in a 10 pct HC1 water solution, rinsed in ethanol, dried, and cemented into brass grips with an epoxy resin. In addition to the torsion specimens, several tensile specimens with their basal planes at 45 deg to the stress axis were also prepared with similar dimensions except that the gage sections were increased to 4 in. in length. The torsion specimens were tested in the apparatus

Jan 1, 1970