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The Development of Research and Quality Control in the Modern Steel Plant. By Leo F. Rein-artz. (Metals Technology, April 1943) Blast Furnace and Raw Materials Essential Considerations in the Design of Blast Furnaces. By A. L. Foell. (,Metals Technology, December 1942) Results Obtained from Surveys of Gas at Furnace Tops. By James M. Stapleton. (Metals Technology, January 1943) Physical Aspects of the Dust Catcher, Gas Washer and Precipitator on No. 3 Furnace at Carrie. By C. P. Clingerman and C. J. FleiscH. (Metals Technology, January 1943) Slag Control by Introduction of Flux through Blast-furnace Tuyeres. By Carl G. Hogberg (Metals Technology, January 1943) The Electrical Conductivity of Molten Blast-furnace Slags. By A. E. MaRtin and GerRard Derge. (Metals Technology, August 1943) Some Physical Characteristics of By-product Coke for Blast Furnaces. By CEarles C. Russell and MichaeL Perch. (Metals Technology, December 19+2) Pyrometry at the Coke Oven. By Robert B. Sosman. (Metals Technology, December 1942) Calcination Rates and Sizing of Blast-furnace Flux. By T. L. Joseph, H. M. Beatty and Gust Ritsianes. (Metals Technology, December 1942) The Low-temperature Gaseous Reduction of a Magnetite. By M. C. Udy and C. H. Lorig. (Metals Technology, October 1942) Steelmaking Problems of Total Operation in Steelmaking. By William C. Marshall and Frank G. Norris. (Metals Technology, April 1943) Silicon-oxygen Equilibria in Liquid Iron, By C. A. ZapFFe and C. E. Sims. (Metals Technology, September 1942) Equilibria of Liquid Iron and Simple Basic and Acid Slags in a Rolating Induction Furnace. By C. R. Taylor and John Chipman. (Metals Technology, September 1942) Rapid Analysis of Oxygen in Molten Iron and Steel. By Gerhard DeRGe. (Metals Technology, January 1943) Silver Chloride as a Medium for Study of Ingot Structures. By Karl L. Fetters and Margaret Dienes. (Metals Technology, August 1943)

Jan 1, 1943

By D. W. Fuerstenau

THE object of this article is to point out the experimental relationship which exists among contact angle, adsorption density, zeta potential, and flotation rate data. In each of the experiments discussed in this article, the surface properties of quartz, as a function of pH, were measured in solutions to which constant quantities of dodecylammonium acetate were added. Morrow1 and deBruyn2 worked with solutions containing 4.08x10-5 moles per liter, whereas Fuerstenau3 and Seele worked with solutions containing exactly 4x10 moles per liter, but this difference is not significant. The pH of the solutions was regulated with HCI or NaOH in all cases. In each case, the addition of collector was constant, but the concentration of dodecylammonium ions decreased because of the formation of dodecylamine at higher pH values2 Contact Angles: Gaudin and Morrow1 presented data for the contact angle of quartz in solutions containing 4.08x10-5 moles of dodecylammonium acetate per liter between pH 2 and pH 10.15. Using the same captive bubble techniques, the writer measured contact angles on quartz in solutions containing 4x10-5 moles of dodecylammonium acetate per liter at pH values ranging from 9.9 to 13.2. Both sets of data are presented in Fig. 1, in which the contact angle in degrees is plotted as a function of the pH of the solution. From pH 2 to about 8, the contact angle increases slightly with increased pH, but further increase in pH causes a sharp rise in the contact angle to a maximum of about 80º. At pH values above 11.6, the contact angle drops sharply, reaching zero by pH 12.6.

Jan 12, 1957

Jan 1, 1925

By Carl J. McHargue

Mechanical twins were produced in electron-beam melted columbium by high-speed impact at room temperature and by slow or fast compression at -196°C. The composition plane of the twins was { 112} and the shear direction was <111>. Notches in the twin bands often corresponded to traces of {110) of the matrix and appeared to be untwinned regions. Markings within the twin bands were interpreted as resulting from {110} slip in the twins. THERE has been much work in recent years concerning plastic deformation by glide, and the dislocation theory relating to glide has reached a relatively high degree of development. On the other hand, there have been fewer studies of deformation by mechanical twinning, and understanding of this process is far from satisfactory. This method of deformation is of interest for at least two reasons. First, it provides a mechanism in addition to glide for the relief of stresses, and, in the bcc and hexagonal close-packed metals may result in significant amounts of plastic flow. Secondly, there is the possibility that twins may act as barriers for dislocation movement, resulting in pile-ups which could nucleate cracks. As might be expected, the bulk of the literature on mechanical twinning in the bcc metals is concerned with iron. A good summary of the work done prior to 1954 is contained in the book by all.&apos; Recently the refractory bcc metals have become increasingly important. Limited studies have shown that tantalum,2,3 molybdenum,4,5 vanadium,6,7 tungsten,&apos; and columbium9-11 deform by mechanical twinning under some conditions. Alloys of molybdenum with rhenium and tungsten with rhenium show extensive deformation by twinning at room temperature.I2-l4 Most of these studies have dealt primarily with mechanical properties at low temperatures or have shown the existence of twins, and there is only a small amount of information concerning the conditions under which they form. The subject of the present paper is the formation of twins under stress in columbium with a consideration of their morphology. EXPERIMENTAL PROCEDURE The material used for these studies was taken from an ingot of columbium which had been melted twice by the electron-be am-method. The analysis of the ingot was (in ppm): B < 1, C = 10, Fe < 100, The cast ingot contained very large grains, and it was possible to obtain single-crystal prisms which measured from ¼ to 3/4 in. on a side. A few experiments were conducted on polycrystalline plate which was prepared by rolling material from the same ingot at room temperature and annealing at 1000 in a dynamic vacuum of 10-6 mm Hg. This gave a plate in which the grains had an average diameter of 3 mm. After the specimens were cut from the ingot, the six faces were metallographically polished and elec-tropolished to remove all traces of cold work. Most of the observations were made on the surfaces of the deformed specirllens without further treatment. Occasionally, etching after deformation was desirable. In these cases, an etchant of the composition 50 parts H2O, 5 parts HNO3 25 parts HF, and 10 parts H2SO4 was found to delineate the twins very well. Unless considerable care was taken to ensure the removal of all disturbed metal left by the mechanical polishing, etching failed to reveal many of the features discussed in this; paper. The specimen&apos;s were deformed either by impact or slow compression at 77°K (liquid-nitrogen coolant), 198°K (dry ice and acetone coolant), and 298°K. The impact load was delivered by a hammer except in one case where the load was delivered by a bullet. Slow compression was carried out on a hydraulic testing machine equipped with a chamber to hold the coolant. EXPERIMENTAL RESULTS It has been generally believed that the conditions favoring the formation of deformation twins are large grains, low temperature, and impact loading. In fact, Barrett and Bakish2 found twins in tantalum only after impact deformation at 77°K, and Adams, Roberts, and Smallman10 observed twins in columbium only at 20 For these reasons, the initial experiments of this study used impact loading. Hammer blows caused many bands resembling twins in single crystals a.t 77" but not at 198°K. Only a few slip lines were observed on any of the single-crystal specimens of this study—essentially all the deformation occurred by twinning. The appearance of the twins on the as-deformed surface is shown in Fig. 1. Although both Figs. 1(a) and l(b) are photomicrographs of twins taken at the same magnification and from the same crystal, they are startlingly different in appearance. Fig. 1(a) was taken from the crystal face approximately perpendicular to the shear direction, whereas Fig. 1(b) was taken from

Jan 1, 1962

By M. L. Leonardi

THE Searles Lake orebody is located in the north- west corner of San Bernardlno County. It is a dry lake bed with an exposed salt surface covering an area of 12 square miles. Recoverable mineral values are contained in the mother liquor below the surface of the lake. Stratification in the lake bed has separated the brine into two bodies which dlffer in composition. Although liquor is processed from both bodies, this paper will discuss only the upper structure brine. Fig. 1 illustrates a typical cross-section of the two commercial orebodies. The orebody is composed of a porous salt deposit 70 to 90 ft deep. The upper structure is separated from the lower orebody by a 12 to 16-ft thick impervious mud seam, as shown in Fig. 1. These salt structures are composed of 55 pct solid-phase salts and 45 pct voids which are filled with the original mother liquor. The brine wells are drilled to the separating mud seam and cased to wlthin 10 ft of the bottom. This is done to draw the brine horizontally from the bottom of the structure. It is pumped with multistage centrifugal pumps Into the plant at the rate of 3 milllon gal per day. The first process that was successful was developed by Charles P. Grimwood for the recovery of potash. The first evaporator unit was built in 1916. In the early twenties, Dr. Morse worked out a process for the recovery of borax. This made the cycle more efficient, as the end liquor could be sent back to the evaporators rather than being sewered. In 1926 the American Potash & Chemical Corp. was formed as a new company, and the entire plant was remodeled. The plant at that time produced only potash, borax, and boric acid. Since then the American Potash & Chemical Corp. has added processes for the production of USP boric acid, refined potash, sulphate of potash, soda ash, salt cake, lithium concentrates, Pyrobor (Na2B4O7) bromine, phosphoric acid, and lithium carbonate. The main plant cycle may be depicted as a closed cycle, see Fig. 2. The raw material, brine, enters the cycle to be mixed with the end liquor, known as ML2, from the pentahydrate borax crystallizers. The mixture of these two forms evaporator feed. Evaporator feed is pumped to the evaporators where it is concentrated, with respect to potash and borax. In the same operation water vapor, sodium chloride, salt trap salt, and clarifier salt are removed from the cycle, see Fig. 3 for potash plant product. The evaporators produce a concentrated liquor which contains approximately 19.5 pct KCI. This liquor is diluted as it enters the potash plant to keep all salts, except potash (KCI, 97.0 pct) in solution. Here the moist potash leaves the cycle at 100°F. The end liquor, known as ML1, is pumped to the borax pentahydrate crystallizers, where crude borax pentahydrate is crystallized and removed as solid phase. The ML2 is sent back to pan feed to be reconcen-trated, see page 207. Note that the only water to leave the cycle is in the form of vapor and moisture in the solid phase products crystallized. Thus there is a constantly cycling volume of liquor to which brine is added. Since the volume of liquor cycled does not increase, the brine is, in effect, evaporated to dryness. This would be true if there were no liquor losses. But, as in all processes, there are always unavoidable and accidental losses which reduce the volume of cycling liquors. The losses must be made up with brine. The concentration process is the beginning and the end of the cycling liquors. In this process there are three evaporator units of the triple effect counter-current type, that is, there are three pans in each unit and the heat flows in one direction while the liquor flows the other way through the evaporator pans, see Fig. 4. During the evaporation process a great deal of sodium chloride, burkeite, some sodium carbonate monohydrate, and a little lithium-sodium phosphate are crystallized. The volume of these salts is so great that they must be removed as they are formed or the process would come to a standstill. Brine and recycled mother liquor No. 2 enter the third effect evaporator pan from the evaporator feed storage tanks, see Fig. 5. A steady flow of liquor is removed from the bottom of the No. 3 pan and is pumped through the No. 3 cone of the salt trap, a clear liquor being returned to the NO. 3 pan. A portion of this clear liquor is pumped to the second effect pan. This process is repeated in each pan. The liquor from the No. 2 pan is pumped through the No. 2 salt trap cone and returned to the No. 2 pan.

Jan 1, 1955

By HAROLD E. WHITE

LONG before the Stone Age, when man first sought shelter where there-were no natural shelters, such as caves and clefts in the rock, he uprooted trees and planted them upside down so that the roots formed the roof. By selecting trees whose roots grew out in a horizontal direction and; by planting these trees close enough - together, a crude shelter was formed. He then took mud, formed a plaster and covered over the&apos; roots. Later the walls were made by using sticks and twigs and plastering between them. It is natural then, that he wiped his muddy hands on- his own hairy body and soon found that the mud was difficult to remove when, dry. It is due, to this discovery that we mix animal hair in &apos;our modern plaster to increase its strength. The use of fibrous asbestos in some refractory cements has followed this same principle.

Jan 1, 1929

ARTHUR PHILLIPS,* Bridgeport, Conn. (written discussion?).-It is to, be regretted that the very valuable paper by Messrs. Bassett and Davis did not appear in the early war period. The data presented would have been of inestimable service to inspectors, of cartridge brass who, admittedly, had little or no knowledge regarding the relation of grain size to temperature of anneal, and no real appreciation of, the significance of the Brinell hardness test. The paper is of considerable interest to, metallurgists also. WALTER R. HIBBARD, ? Bridgeport. Conn. (written discussion§).-The writer has carefully studied Messrs. Bassett and Davis&apos;s paper with considerable interest, inasmuch as our laboratory has tested cartridge brass by means of a Brinell machine. In March, 1917, at the suggestion of the Technical Department of the American Brass Co., we started a comparison of grain-size measurements and Brinell hardness of-cartridge brass with a gage of 0.1 in. or greater. This was continued until March, 1918, when we adopted the Brinell hardness test as standard for brass 0.1 in. gage or greater, and discontinued grain-size measurements upon this metal. The data collected during the test showed that the Brinell hardness indicated more accurately how the metal acted in actual working operations. It was also more reliable because two manipulators check themselves closer by the Brinell test than by the grain-size measurements. It also consumed less time in making the tests. Alfred V. de Forest, formerly assistant research engineer of our laboratories, has described the apparatus and some of the checking results in a paper read June, 1918, before the American Society for Testing Materials.1 The writer hopes that a more satisfactory. method for testing cartridge brass and gilding in gages thinner than 0.1 in. may be devised than the present method of grain-size measurements.

Jan 3, 1919

By E. Mcl. Tittmann

Deep-seated human instincts urge us to positively mark the passage of time. We celebrate the passage of each year. Years give way to decades, and decades to half centuries and centuries. At all these mileposts we are inclined to pause, take a look around and catch our breaths before embarking on the next leg. We are at such a point now and this meeting I am sure will give direction to the road ahead into the decade of the seventies. In looking around at this point, 1973, it is obvious to all of us that the environment in which we must mine, mill, smelt and refine lead and zinc has radically changed. These changes have, of course, occurred over a long period of time. They have, however, all been in the same general direction. They have all had the same motivation. The period of greatest contrast is probably the fifteen years just before World War II and the fifteen years following the end of that war. I thought that I might review briefly with you what seems to me to be four of the more important changes that have developed since World War II that profoundly affect our activities in the lead and zinc industry. I mentioned before that all these changes have been in the same direction; that is, they have all tended to restrict our freedom of action in pursuing our objective of producing lead and zinc on a competitive basis at a profit. Consequently, in discus- sing them you may think that I am merely viewing with alarm. This is not the intent. This is merely supposed to be an objective analysis. I think it appropriate before discussing these trends in de- tail to examine the position of lead and zinc today.

Jan 1, 1970

By W. Denham Verschoyle

In designing a pocket instrumeut whereby any giver1 horizontal or vertical angle may be closely approximated, the following points should be kept in view, if general utility is aimed at : 1. The instrnment should be light and compact, so that it can be carried in the pocket, or in a sling. 2. It should be capable of observing any angle whatever, horizontal or vertical. 3. Since time is often an important consideration in making a preliminary survey, it should be capable of giving the horizontal and vertical angle at one observation. I do not know of any instrunlent that will fulfill these requirements, except the one here described. Where the depression- or elevation-angle of the distant object, whose bearing is required, exceeds 50 or 60 degrees, it becomes difficult or impossible with a prismatic compass, for instance, to obtain accurate results; and since it frequently happens, particularly in mining, that much work requires to be done beyond that limit, it is obvious that an instrument which can be used to observe a high angle just as easily as a low one, if not absolutely a necessity, will at least be a great convenience. How this a pocket transit" attains to the required degree of universality will be understood from the diagram, Fig. 1, in which B is a beveled, graduated circle, attached to and freely revolving about the center of the magnet A. Light falling on B is reflected through a window in F (the compass-box), along the line AC, and is again reflected back to the eye at D by the prism C. By a simple arrangement, the tight-line BCE call be completely revolved in the vertical plane DE, which is normal to AC. It is clear, then, that no matter through what vertical

Jan 1, 1908

By J. Th. Erb

Oil is found in commercial quantities in the islands of Sumatra, Java, Borneo, Tarakan and Ceram. The oil deposits of the Dutch East Indies and Sarawak are with one exception of Tertiary origin and as a rule are bound to anticlinal structures. The number of layers varies in most fields and in some of them asmuch as 14 oil-producing levels have been established. The crude oil varies rather much in composition. Some of it, particularly from North and South Sumatra, has a gasoline content up to 50 Per cent. Borneo produces mainly wax oil, while the Tarakan oil can be used directly as liquid fuel. In Java both wax and wax-free oil are produced. &apos; In all important fields installations have been erected to treat the wet gas. The lean gas is used for gas-lift purposes, Marietta process, and as fuel for boilers and motors, either in the fields or in the refineries. Formerly only percussion systems (Canadian, Californian and a drilling system devised especially for the purposes of the Royal Dutch Petroleum Concern) were applied in the Dutch East Indies, but in recent years the rotary system has been predominant and good results have been obtained with it. The deepest producer has recently been struck in South Sumatra at a depth of 1624 m. (5328 ft.), with a daily production of about 350 cu. m. crude oil. The crude is brought by an extensive system of trunk lines to the refineries, of which one is in North Sumatra (Pangkalan Brandan), two arc in South Sumatra near the town of Palembang, two in East ,Java (Tjepoe and Wonokromo), one in East Borneo (Balik Papan) and one in Sarawak (Miri). Production The principal producing concerns in the &apos;East Indies are: De Bataafsche Petroleum Maatschappij, the producing subsidiary of the Royal Dutch Petroleum Concern; Sarawak Oilfields Ltd., one of the

Jan 1, 1929

Henry Louis, Newcastle-upon-Tyne, England (communica, tion to the Secretary): I have been much interested in Mr. Schmitz&apos;s description of the copper-ore bed in the Permian formation of Texas. He compares it with the Mansfeld Kupferschiefer; but it seems to me to present closer analogies with a small deposit on the same side of the Atlantic, in Nova Scotia, which I examined in 1877. I quote entirely from my fieldnotes, made then, and from specimens still in my possession. These copper-deposits are known in several places; but I examined them at the village of New Annan, on the banks of the French river. This district has been determined by Sir J. W. Dawson as being of Permian age, and this determination seems to have been confirmed as recently as 1891 by the operations of the Canadian Geological Survey. The following is the section, very imperfectly exposed in a few shallow levels, described in ascending order: Red sandstone, moderately fissile and markedly false-bedded. Lower nodule-bed, 1 inch to 6 inches thick, of fissile mica, ceous sandstone, containing obscure plant-remains converted into anthracite, chalcopyrite, chalcocite and iron pyrites. Very coarse grit or, in places, red sandstone; thickness and character variable. Upper nodule-bed, 6 inches to 2 feet thick exceptionally, generally about 10 inches. Soft, gray, friable shaly sandstone, with nodules of copper-ore. Red sandstone. All these strata lie flat, in places quite horizontal, in places dipping towards the river at 5° to 10°.

Jan 1, 1897

By A. A. Burr, D. Caplan

IN carrying out experiments in metal-gas systems, it is often difficult to estimate how long a reaction period must be allowed for equilibration. This is especially true in systems for which the diffusion coefficient is not known. In an investigation of the Cr-O system, the necessary information was obtained in the way described subsequently. Two pieces of chromium sheet of different thicknesses were packed in mixed powders of chromium and Cr2O3 and sealed into an evacuated metal capsule by welding. Austenitic stainless steel proved suitable as a capsule material up to 1350°C and molybdenum at higher temperatures. The capsule then was heated at a specific temperature for a time sufficient to saturate with oxygen the thinner but not the thicker specimen. The time is readily estimated from a preliminary experiment if a sufficient thickness differential is chosen. Under these experimental conditions, the metal sheet is exposed to a partial pressure of oxygen equal to that of the dissociation pressure of the oxide and hence can become saturated with oxygen without developing any second phase. After cooling, both samples were analyzed for oxygen by the vacuum fusion technique. Assuming that the surface of the specimens is kept saturated with oxygen throughout the experiment, the diffusivity can be calculated by application of the appropriate solution to Fick&apos;s second law. This is most conveniently accomplished by use of a plot of mean fractional saturation (Cm-Co) / (Cs-Co) vs (Dt) ½/L as given by Darken,&apos; where t is time, L the half-thickness of the sheet, and D the diffusion coefficient. Cm, the mean concentration at time t, is given by the oxygen percentage in the thicker specimen; Cs, the constant surface concentration, is the oxygen percentage in the thinner specimen; Co is the oxygen content of the original chromium sheet. (Cm-Co) / (Cs-Co) is calculated and the corresponding (Dt) ½/L is read from the graph and D thereby calculated. By performing the experiment at two temperatures and plotting log D vs 1/T, the D for any temperature is established. (The activation energy for diffusion may be obtained from the slope of the line.) Once D is known as a function of temperature, it is a simple matter to estimate the correct reaction time for experiments with single specimens at other temperatures by equating (Dt) ½/L to its value for effective saturation. Darken&apos; points out that this is approximately unity. The solubility of oxygen in chromium, as determined from the thin samples at each temperature, proved to be approximately 0.03 pct at 1350°C and less at lower temperatures. Due to low solubility and to the known difficulties of the vacuum fusion method in this low range, the values obtained for D (5x10-0 sq cm per sec at 1350°C) are estimated to be correct only within an order of magnitude. Nevertheless, the method has proved useful in estimating reaction times. Its usefulness will be greater in metal-gas systems where the solubility is appreciable. A second function of the method is to permit the determination of diffusion coefficients in systems for which the conventional techniques are experimentally difficult or impossible.

Jan 1, 1956

By George Smith

IN discussing present-day business and industrial troubles we easily drop into the habit of clinical diagnosis. Talk of this kind, with its emphasis on suspicious symptoms and abnormal tendencies, makes us all morbid. As an English essayist has put it, we may thus induce a melancholy, temper that simply in-vites the ministrations of social and political quacks. It is far better-because nearer the truth-for us to recognize that our condition is in no sense diseased, that our body politic, social and economic, is suffering merely from growing pains; that America is not de-cadent-indeed, that any lapses from staid normality are traceable to the, excesses of youth. Our chief .trouble, then, is only that our industrial state is still young; it may be that we have been growing too fast. The growth in the industrial development of our country from pioneer days to the present time has been marvelous. Too many of us, however, take all this as a matter of course-we credit this record of American progress to our American genius alone. Too often we overlook the fundamental relationship between resources and progress-that man is aided and even guided by Nature. The fact is, social advance, indus-trial progress, national prosperity all have their ma-terial basis in natural resources. In furnishing the needed mineral raw materials to the great manufac-turing industries of the United States there has been no halt, but rather a general acceleration. No other phase of American activity can show-equal advance. As the decades have passed, the winning of mineral wealth has progressed from the role of a stimulus for western exploration to that of the foundation for nation-wide business. In 1890 the Sherman law was passed; since then the population of the United States has about doubled. Since then, too, thevalue of the annual product of the mines of this country has increased better than eight-fold-from 650 millions to 51/ billions of dollars. Since then the four largest branches of the mineral industry, which supply the iron and copper, the bituminous coal and petroleum-the bone and sinew and the energy of all other American industries-have increased their annual output nearly ten-fold as to value and six-fold as to quantity. Such a growth in the volume of mineral output must be taken as a true measure of the ex-ceptional service rendered by the mines of the United States. Not only is this a much larger country than it was 38 years ago, but its growing mineral industry has met demands that have been out of all proportion to the growth of the population.

Jan 8, 1928

By AIME AIME

SCANDINAVIAN countries seem somehow to furnish an amount of talent and leadership far be- yond their population and among them Sweden is possibly at the top. The United States has many eminent citizens born in the latter, country or who are of Swedish descent and the engineers may claim their full share. In fact, the number is so large that a flourishing Swedish-American Engineering Society has been formed, including a number of A. I. M. E. members. Dr. Waldemar Lindgren is more scientist than engineer, though his work in economic geology has contributed directly to the development of many mines, and he is the valued- adviser of a number of our larger companies. Probably he, himself, values most highly the contributions he has been able to make to scientific theories of the occurrence and genesis of ore deposits. His fellow scientists have placed upon these the high mark of approval by electing him to the National Academy of Sciences, and Princeton University in 1916 recognized his position by conferring on him the degree of Doctor of Science.

Jan 1, 1931

By P. A. Witherspoon, R. W. Donovan, T. D. Mueller

The use of petroleum-barren aquifers for underground storage has become extremely important to the natural-gas industry. A critical problem in assessing the feasibility of a specific aquifer for such use is the permeability determination of the caprock over the proposed storage project. The approach used here is to conduct both static and dynamic field tests on the aquifer being analyzed. Valuable information on the possibility of communication between the storage aquifer and any other aquifers above can be obtained by measuring hydrostatic water levels and water analyses. Significant differences in such data give evidence of the lack of communication between the intended storage reservoir and other horizons. The dynamic approach requires that one well be pumped in the storage aquifer, and changes in fluid levels recorded in both the aquifer and its caprock. The interpretation of the data from such pumping tests involves the solution of nonsteady radial flow in an infinite aquifer and the influence on such flow of a leaky caprock. A finite-difference model has been used to investigate this problem, and the transient behavior has been solved numerically with a digital computer. It has been found that the pressure transients in the storage aquifer are not affected significantly by moderate caprock leakage. The pressure behavior of the caprock is a much better indicator of the degree of leakage, and generalized solutions for this behavior are included. Field data are presented to demonstrate both the static and dynamic approach. If is concluded that appropriate investigation of the groundwater hydrology in an aquifer-type gas-storage project can provide much valuable information for determining the effectiveness of the caprock to hold gas. INTRODUCTION Underground storage of natural gas in the United States has been developing at a rapid rate over the past few years. In 1955, the total gas-storage capacity was about 1.6 trillion cu ft; by 1961, this figure was almost 3.2 trillion cu ft, an increase of 100 per cent in six years.&apos; This trend un- doubtedly will continue because the economics favor the development of gas storage, as opposed to the construction of new pipelines, to meet the inherent cyclic demand for fuel in the metropolitan areas of this country.&apos; About 15 per cent of the current underground gas storage has been developed in petroleum-barren aquifers, i.e., geological domes or anticlines in which no commercial quantities of oil or gas had been produced prior to the storage operations. The necessity for using barren aquifers outside many metropolitan areas of this country has been due to the lack of depleted oil or gas fields that were near enough and large enough to meet the demands of such consuming areas. Pipeline companies have developed aquifer storage along their transmission lines to meet the fluctuating needs of their complex systems. Considerable thought has also been given to the problem of storing gas in a structureless aquifer, both in this country&apos; and in the Soviet Union outside the city of Leningrad.&apos;," Conditions such as these have led to the development of aquifer gas-storage projects in many parts of the U. S. Most of these developments have centered in the Mid-Continent area, and the greatest amount of activity has been concentrated in Illinois.6 Thus, the use of petroleum-barren aquifers for gas-storage purposes has become extremely important to the natural-gas industry. There are three basic problems in developing aquifer-type storage: (1) finding an adequate geologic structure, (2) finding a suitable storage reservoir within the structure and (3) determining the tightness of the caprock over the intended storage zone. The first two problems can be solved by applying conventional methods of exploration geology, but once these problems are solved, the question arises as to why no oil or gas is present in an otherwise favorable setting. Two situations are possible: (1) an adequate source bed was never present, or (2) a source bed was present but the petroleum seeped away because of a leaky caprock. Determining the tightness of the caprock is one of the most critical problems in assessing the feasibility of a specific aquifer for storage purposes. In attacking this problem, one usually takes cores of the caprock and subjects them to a rigorous investigation. Such core data are desirable, but they only detail the matrix properties and cannot be expected to reveal the gross characteristics of the caprock. Several gas-storage projects in the U. S. have had considerable leakage where

Jan 1, 1902

By R. I. Jaffee, F. C. Holden, H. R. Ogden

ECENT papers dealing with the properties of unalloyed iodide titanium have been directed primarily at the determination of base-line properties for alloy investigations. Early work was limited to a few tests because of the limited availability of iodide titanium at the time. In the results of papers by Campbell et al.,1 Gonser and Litton,2 Jaffee and Campbell,3 inlay and Snyder,4 and Jaffee, Ogden, and Maykuth, data on mechanical properties are presented for unalloyed iodide titanium in the annealed and cold-worked conditions. Data are presented in this paper which show the effects of heat treatment on the structure and mechanical properties of commercially produced iodide titanium. Correlation is made between microstruc-tural variables and the mechanical properties. Experimental Procedures Melting Stock: The melting stock used was as-deposited iodide titanium, produced by New Jersey Zinc Co. The furnished analysis showed the following range of impurities: N, 0.004 to 0.008 pct; Mn, 0.005 to 0.013; Fe, 0.0035 to 0.025; Al, 0.013 to 0.015; Mo, 0.0015; Pb, 0.0045 to 0.0065; Cu, 0.0015 to 0.002; Sn, 0.001 to 0.01; Mg, 0.0015 to 0.002; and Ni, 0.003. Hydrogen content as determined by vacuum-fusion analysis was 0.0091 wt pct (0.44 atomic pct) after arc melting and fabrication. Nitrogen analysis on the arc-melted and fabricated titanium showed a content of less than 0.002 pct N. The average hardness of the furnished stock was Rf 70, or approximately 85 VHN. Melting Procedure: The as-deposited rods were rolled, sheared, and degreased in preparation for arc melting. The charge was arc-melted with a tungsten electrode in a water-cooled copper crucible under a positive pressure of high purity (99.96 pct) argon. The final ingot was approximately 2 in. in diameter and showed no increase in hardness over that of the initial stock. Fabrication: Heating for fabrication was done in air. It was begun by forging the ingot into a 3/4 in. diam rod, at an initial temperature of 1600°F. Scale was removed by sandblasting. The rod was then swaged to 1/4 in. diam at room temperature through a series of 20 dies, with approximately 10 pct reduction in area between each die. An anneal of 1 hr at 850 °C in air was given after the 1/2 in. die, such that the final cold reduction was 75 pct. Sections cut from this rod were used for test and microstructure specimens. Heat Treatment: Heat treatments were carried out in resistance tube furnaces with stainless-steel linings, under an atmosphere of gettered argon. As further protection against contamination, the specimens were packed in titanium turnings in a titanium sleeve. Control experiments have shown negligible hardness increases with this method, indicating that contamination from oxygen and nitrogen is slight. Three cooling rates were employed in this work; these have been designated as water quenching, argon cooling (to simulate air cooling under a controlled atmosphere), and furnace cooling. The cooling rate for an argon cool is 100°C per min for the first minute, with an average cooling rate of 35°C per min over a 15-min period. A furnace cool requires about 10 hr, with an average cooling rate of 3.6oC per min during the first hour, and an average cooling rate of 1.2°C per min over the 10-hr period. Microimpact Test: The specimen adopted was based on the cylindrical Izod Type Y specimen (ASTM, E23-41T). All dimensions were reduced to half scale, including the notch radius. Specifications are shown in Fig. 1. The specimen is held vertically in an adapter and broken as a cantilever beam. Impact tests were run on a constant-velocity (11.34 ft per sec) Tinius Olsen impact testing machine with a total available energy of 100 in.-lb. Tests were made to determine the correlation between this microimpact and the standard V-notch Charpy impact test. Curves showing impact energy as a function of temperature for both impact tests are plotted in Fig. 2. Transition temperatures, when they occur, are about the same for both impact tests. All three titanium-rich materials have the same conversion factor, 10. Tensile Testing: Tensile tests were conducted on Baldwin-Southwark testing machines using the 600, 2400, or 3000 1b range. Specifications for the test specimen were taken from the 1948 edition of the ASM Metals Handbook, and are shown in Fig. 1. Strain measurements were made using an SR-4 resistance gage (Type A-7) cemented to the reduced section in conjunction with a lever-type extenso-meter. Readings on the SR-4 strain indicator were

Jan 1, 1954

By Walter L. Rice

It is a pleasure to report that the light metals industries are running well ahead of the growth schedule projected by the President&apos;s Materials Policy Commission. In the compilation of this survey on the five-year growth of our light metals industries, some gratifying facts come to light. By 1956, for instance, light metals consumption had increased more than 20 pct beyond Paley report expectations-a growth not anticipated by the study until the year 1960.

Jan 9, 1959

By Shiou-Chuan Sun, R. F. Wesner, J. D. Morgan

0. C. Ralston and F. Fraas—Dr. Sun and associates have presented an interesting paper not all of which is comprehended by us. The data assembled measure the deflections of particles in an electrostatic field as a function of a number of independent variables and some dependent variables that are not sharply differentiated. These data are all based on a Johnson type machine of definite, well-described geometry, something not often done in electrostatic separation literature. One new fact brought out by this technique is the effect of coal dust on admixed pyrite and quartz. The effects are opposite in character, as should be expected and we do not agree with the authors that these effects are negligible. Fraas&apos; also used a multiple cell "distribution analyzer" and gives in fig. 5 of his paper a straight line plot with no humps or curves. This is not necessarily at variance with Sun&apos;s results because Fraas used a larger gap between electrodes and had no evidence of particles adhering to or dropping off the charged electrode. The section of Sun&apos;s paper on effect of surface conductivity contains a speculation that the dielectric constant "represents more or less the electrical conductance of the bulk body instead of the surface of the mineral particles." A simple picture of the meaning of the dielectric constant is that it is the specific inductive capacity of a dielectric when used as the dielectric between the plates of a condenser. It is at once evident that the above speculation confuses capacity with conductance—two definitely independent variables. We ask the authors to state in what group or subdivision their garnet belongs; what method and units were used in calculating the data of col. A, table I and their meaning; what was the temperature of the carrier roll and, finally, has any effort been made to investigate the effects of particle shape on distribution in the electrostatic field? S. B. Hudson—I have read this article with great interest. We have been engaged in research work on the principles of electrostatic separation in this laboratory for some time now, and our findings agree with those of the authors in many respects. The article shows evidence of careful and valuable research in the field of electrostatic separation. A "distribution analyser," very similar to that described in an earlier article by one of the authors," was incorporated in an inclined plate-type electrostatic separator designed and built in the Melbourne University laboratory in 1948 for investigation purposes.22 The actual splitting edges were machined from y! in. per-spex, and the paper hoppers were supported on linen thread immediately below the perspex dividers. These dividers fitted into machined slots in a framework to give accurate Yz-in. spacings. The hoppers (staggered) fed directly into a rack of test tubes, which is supported on a vertical pantograph arrangement. The rack was positioned with guides on the horizontal pantograph stand, and this ensured positive alignment when replacing the rack after making weighings. In later work, when much heavier feed rates were used, of the order of 30 to 40 Ib per in. per hr a rack fitted with rectangular metal containers and similarly aligned was used. Some work was done here on comparing the distributions of minerals when passed separately and when passed as a mixture, and it was found that there was quite an appreciable difference in the two results.= However, in our separator the particles do not pass down the plate in a single layer, and this difference is probably caused by collisions of one mineral particles with the other mineral particles. In most of the investigational work here, the change of the center point of the distribution is measured to establish the effect of a variable, such as voltage. Two minerals (zircon and rutile) have been studied rather exhaustively, and it was found that their distributions are very nearly normal. Owing to the sharpness of the distribution curves, the usual method of obtaining the mean or median was inaccurate, and was not used; instead the mean (also the median), calculated on the assumption of a normal distribution, was used to locate the center point of each distribution and proved satisfactory. The effect of polarity becomes very apparent in the plate-type separator where frictional charges play a very important part when using highly resistive minerals such as zircon. With rutile, a comparatively conductive mineral, polarity of the electrode has little effect. On the other hand, the magnitude of the voltage has a far greater effect on conductive than on resistive minerals. Shiou-Chuan Sun (authors&apos; reply)—Thanks are extended to Drs. Ralston and Fraas for their keen interest in this paper. Their questions concerning coal dust,

Jan 1, 1951

By Shiou-Chuan Sun, R. F. Wesner, J. D. Morgan

0. C. Ralston and F. Fraas—Dr. Sun and associates have presented an interesting paper not all of which is comprehended by us. The data assembled measure the deflections of particles in an electrostatic field as a function of a number of independent variables and some dependent variables that are not sharply differentiated. These data are all based on a Johnson type machine of definite, well-described geometry, something not often done in electrostatic separation literature. One new fact brought out by this technique is the effect of coal dust on admixed pyrite and quartz. The effects are opposite in character, as should be expected and we do not agree with the authors that these effects are negligible. Fraas&apos; also used a multiple cell "distribution analyzer" and gives in fig. 5 of his paper a straight line plot with no humps or curves. This is not necessarily at variance with Sun&apos;s results because Fraas used a larger gap between electrodes and had no evidence of particles adhering to or dropping off the charged electrode. The section of Sun&apos;s paper on effect of surface conductivity contains a speculation that the dielectric constant "represents more or less the electrical conductance of the bulk body instead of the surface of the mineral particles." A simple picture of the meaning of the dielectric constant is that it is the specific inductive capacity of a dielectric when used as the dielectric between the plates of a condenser. It is at once evident that the above speculation confuses capacity with conductance—two definitely independent variables. We ask the authors to state in what group or subdivision their garnet belongs; what method and units were used in calculating the data of col. A, table I and their meaning; what was the temperature of the carrier roll and, finally, has any effort been made to investigate the effects of particle shape on distribution in the electrostatic field? S. B. Hudson—I have read this article with great interest. We have been engaged in research work on the principles of electrostatic separation in this laboratory for some time now, and our findings agree with those of the authors in many respects. The article shows evidence of careful and valuable research in the field of electrostatic separation. A "distribution analyser," very similar to that described in an earlier article by one of the authors," was incorporated in an inclined plate-type electrostatic separator designed and built in the Melbourne University laboratory in 1948 for investigation purposes.22 The actual splitting edges were machined from y! in. per-spex, and the paper hoppers were supported on linen thread immediately below the perspex dividers. These dividers fitted into machined slots in a framework to give accurate Yz-in. spacings. The hoppers (staggered) fed directly into a rack of test tubes, which is supported on a vertical pantograph arrangement. The rack was positioned with guides on the horizontal pantograph stand, and this ensured positive alignment when replacing the rack after making weighings. In later work, when much heavier feed rates were used, of the order of 30 to 40 Ib per in. per hr a rack fitted with rectangular metal containers and similarly aligned was used. Some work was done here on comparing the distributions of minerals when passed separately and when passed as a mixture, and it was found that there was quite an appreciable difference in the two results.= However, in our separator the particles do not pass down the plate in a single layer, and this difference is probably caused by collisions of one mineral particles with the other mineral particles. In most of the investigational work here, the change of the center point of the distribution is measured to establish the effect of a variable, such as voltage. Two minerals (zircon and rutile) have been studied rather exhaustively, and it was found that their distributions are very nearly normal. Owing to the sharpness of the distribution curves, the usual method of obtaining the mean or median was inaccurate, and was not used; instead the mean (also the median), calculated on the assumption of a normal distribution, was used to locate the center point of each distribution and proved satisfactory. The effect of polarity becomes very apparent in the plate-type separator where frictional charges play a very important part when using highly resistive minerals such as zircon. With rutile, a comparatively conductive mineral, polarity of the electrode has little effect. On the other hand, the magnitude of the voltage has a far greater effect on conductive than on resistive minerals. Shiou-Chuan Sun (authors&apos; reply)—Thanks are extended to Drs. Ralston and Fraas for their keen interest in this paper. Their questions concerning coal dust,

Jan 1, 1951