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By G. L. Oldright, F. W. Schroeder

Very great changes were made in the dimensions of the smelting hearths of the furnaces in the period from about 1800 to 1906, the length increasing from about 11 to 116 ft., and the width from 8 to 19 ft. During this time the tonnage smelted increased from about 9 to 250 tons per 24 hr., and the tons of charge smelted per ton of coal increased from 0.77 to 4.3. Dr. Mathewson3 noted no great difference in the "fuel ratio" (i. e., the amount of charge smelted per ton of coal) as the furnace at Anaconda was increased in length by stages from 85 to 116 ft. (The percentage of copper in the slag, however, was lowered from 0.42 to 0.36 per cent. The other components of the slag were not given.) Lump coal fired on grates was the fuel used during this period. The practice in operating the furnaces over such a length of time naturally varied considerably, and there were differences in composition and nature of the charge, yet it may he considered that the improvements made were due largely to increases in the size of the furnace used. Doubtless some credit should be given to improvements in operating technique, like changes in the methods of firing the lump coal. However, the greater part of the advance was probably due to factors influencing the

Jan 1, 1928

By Jack A. Simon, M. E. Hopkins

GENERAL GEOLOGY Coal is defined as a combustible rock that had its origin in the accumulation and physical and chemical alteration of vegetation. Coal can be ignited and burned like the wood that was man's earliest fuel, but coal gives more heat than the same amount of wood and has many industrial uses. Unlike wood, coal is not generally found on the surface of the ground but is mined from the solid rock of the earth. Before taking up the occurrence, formation, and the somewhat unique character of coal in the rock sequence, let us briefly consider the general character of all rocks in the crust of the earth. Relatively little is known about the very earliest history of the earth, although a number of logical theories have been developed. Manned exploration of the moon and the rocks being returned to earth will, we hope, provide some answers to questions concerning the earth's origin and history. The period of earth history with which we concern ourselves here begins after great areas of water had evolved on earth and substantial land areas of once molten (igneous) rock existed. Weathering and other processes that attacked the surface of the rocks reduced them to small particles. Water provided by rainfall transported this material, ultimately, to large bodies of water where it was deposited. Thus was initiated the geologic sequence of sedimentary rocks that lie above the once molten igneous rocks. The crust of the earth is not completely stable, and throughout the geologic past portions of the crust have moved laterally and vertically. Even today, many coastal areas are slowly rising or sinking. More sudden earth movements are recognized by the earthquakes they cause. Throughout geologic history, rises in sea level or the sinking of the land areas have many times permitted the oceans to cover much of what are now the areas of the continents. Only relatively small parts of the present continents appear to have been above sea level throughout geologic time. Great

Jan 1, 1973

By Cyrus Garnsey

NECESSITY FOR PRICE FIXING DURING the latter part of 1916 and the early months of 1917, clue to war activities, there was a threatened shortage of coal which resulted in panic among consumers and a rush to obtain coal at once at any price. As a result of this insistent demand for immediate delivery, prices were bid up by the consumers to unprecedented heights; spot coal which had previously been selling at from $1.50 to 82 per ton was bid up to $5, $6, and, in exceptional cases, as high as $7.50 or more per ton. Then when the April, 1917, contract period arrived, contracts could be made only at prices ranging from $3 up to $5 and $6 per ton for the year's delivery. This condition caused such a demoralization of the business, and so much complaint, that some action to regulate prices was considered essential by the National Administration. LANE-PEABODY AGREEMENT In May, 1917, a committee under the chairmanship of F. S. Peabody, of Chicago, was appointed by the Council of National Defense, through Mr. Lane, to consider the whole question of bituminous coal. This committee, with the Secretary of the Interior, Mr. Lane, after numerous meetings and long negotiations with the operators throughout the country, announced on June 29 an agreement between the Committee and the producers, fixing a tentative maximum price for bituminous coal throughout the country at $3 per net ton f.o.b. mines, to which was added 25 c. for selling commission to wholesalers. This plan was based on the idea of fixing a maximum price, high enough to greatly-stimulate production, with the expectation that the laws of supply and demand would, with ample production, operate to maintain fair and just prices for coal throughout the country.

Jan 9, 1918

By W. L. Saunders

IMPORTANCE OF ROCK DRILLING. IT has been estimated that the value of the mineral products of the United States is about $2,000,000,000 a year; that about $25,000,000 is expended. annually for explosives and that about double this sum is paid in wages where blasting is done. The value of the mineral products does not adequately express the importance of the industry involved in the excavation of rock and ore because of the enormous sums of money expended in tunnel driving, in quarries, and in open-cut excavation generally. We know that the Catskill Aqueduct in the neighborhood of New York, which is now nearing completion, has cost some $165,000,000 and that about one-third of this may be rated as rock excavation. These illustrations are given in order to call attention to the great importance of an industry the extension and development of which in our industrial life depend so much upon the economics of rock drilling. Reference has been made to the new Catskill Aqueduct. There are three aqueducts leading into New York, each built at periods separated by some 20 years of time. 'The first one, known as the Old Aqueduct, conveys the waters of the Croton river to New York City in a manner which reminds one of the old Roman aqueducts, the ruins of which are still in evidence. The engineers who laid out these old conduits sought to direct their lines around the hills and into the valleys, at all times avoiding the rock. When it was necessary to cross a river or a deep ravine, a bridge or causeway was constructed. High Bridge, over the Harlem river, is an arched masonry viaduct differing in no essential features from the aqueducts of the Romans. When the second Croton Aqueduct was built, about the year 1890, the art of drilling rock had been so far perfected, and the use of explosives, through the invention of dynamite, had become ,so general, that this waterway was planned and executed on straight lines, following rather than avoiding the rock. The second Croton Aqueduct is a tunnel through rock, about 32 miles in length; material gneiss, almost as hard as granite. Its construction was made practicable by sinking

Jan 9, 1913

By Arthur Forsyth

A SEARCH through the available literature shows that the cobalt-nickel-silicon system has not been systematically studied. This seems rather odd because all three elements are fairly abundant and have better than average corrosion resistance; however, they have high melting points, which makes experimental work difficult. Cobalt and nickel form a continuous series of solid solutions and each metal dissolves about 7.5 per cent silicon. Many ternary alloys have been studied and the results have been published in a great many different ways, but to present such data in a short but clear and understandable manner is still a problem. The following pages describe the results of the study of 76 alloys from which the partial ternary diagram (Fig. 1) of the cobalt-nickel-silicon system has been drawn. The alloys were chosen according to the plan in Fig. la by taking definite ratios of cobalt and nickel, such as 70 Ni, 30 Co or 40 Ni, 60 Co, and adding silicon in various percentages. Each section was studied in detail by means of thermal analysis and microscopic examination, but only two of these detailed sections were thought necessary in the point perspective drawing to give a comprehensive picture of the liquidus, solidus and solid transformations that take place over the temperature ranges studied. Complete thermal analyses and microscopic data are given in Table 1.

Jan 1, 1940

By David Sinclair

THE dimensions and shapes of mine structures may at present be determined by (1) field experience, (2) structural calculations, and (3) barodynamic tests.§ None of these, however, provide information as to the stresses, their direction and distribution in a mine structure. For the design of pillars, the placing of openings relative to working places such as gangways, haulage levels, etc., this information is desirable. Photoelastic methods provide this and, while relatively new, their appli-cation in all engineering fields is assuming increasing importance. This paper, therefore, will present the method with a few applications to mining, and with sufficient reference for further study by the reader. PART I THE PHOTOELASTIC METHOD The photoelastic method of stress measurement determines the stress distribution in a two-dimensional model by optical means. It makes use of the fact that when a piece of isotropic transparent material, such as glass, celluloid, or Bakelite, is stressed and viewed in polarized** light a picture is seen which indicates by its color bands of light, or fringes, the magnitude of the stresses, their direction and their distribution.

Jan 1, 1940

By G. F. Comstock

In the literature of metallography there is a large amount of material describing the various non-metallic inclusions found in iron and steel, and the appearance of sulfides, silicates, oxides, or alumina in steel under the microscope is fairly well known. The inclusions found in non-ferrous metals are, however, not so well known, at least judging from published writings, and the author has been interested in examining small castings of copper, brass, or bronze with certain inclusions purposely mixed with the metal, to see what was the characteristic appearance of each kind of inclusion, and if they could be readily distinguished from one another. The method employed in most cases consisted in overheating and oxidizing a small charge of copper, then cooling it somewhat, and adding a suitable amount of the element whose oxide it was desired to observe. This element was stirred in well and given time to react with the oxygen in the copper, then the melt was poured in a sand mold in the form of a cylinder about 21/2 in. (63 mm.) in each dimension, with a sprue about 11/2 in. (38 mm.) in diameter and 3 in. (76 mm.) high on top of the cylinder, the sprue forming the only riser. Samples for examination were cut sometimes from the center of the casting, and sometimes from the sprue or riser. A few of these samples were cast in chill molds. The appearance of sulfides was studied in an alloy containing 10 per cent, each of tin and lead, with which a flux of plaster of Paris was used. The appearance of foundry sand was studied in several alloys, one of them having sand stirred into the metal intentionally, and others having cut into the molds badly when poured, so that the castings were spoiled by included sand. As all this work was done on alloys having copper as the chief ingredient, the natural starting point was copper oxide, the appearance of which in a micro-section is well known. Cuprous oxide is soluble in molten copper, but separates out in freezing and forms a eutectic containing 3.5 per cent. Cu20, or 0.39 per cent. oxygen. If there is less

Jan 1, 1919

By E. S. Machlin, Morris Cohen

The isothermal formation of martensite in a 71 pct Fe, 29 pct Ni alloy is found to take place mainly by the nucleation of new plates rather than by the growth of existing ones, and is dependent on the temperature and time of the isothermal hold, the amount of atherrnal martensite present, the state of internal strain, and the application of tensile stress. The conclusion is reached that the isothermal nucleation is activated by thermal fluctuations superimposed on localized regions of very high strain. The reaction-path concept, involving martensite nucleation at strain embryos by athermal activation on cooling, or by thermal fluctuations on holding, reconciles the athermal and isothermal modes of transformation, and offers a unified picture of the kinetics of martensite formation. THE phenomenon of isothermal martensite formation has been the subject of considerable study lately,'-' and its reality has been thoroughly established. The existence of such isothermal transformation has been claimed to confirm the nucleation and growth hypothesis as applied to the martensitic reaction.1 " However, the isothermal formation of a martensitic phase is also compatible with the reaction-pathw escription of the transformation. The purpose of this investigation is to examine the isothermal mode of the martensitic reaction, both theoretically and experimentally, in order to test the likelihood of the above two mechanisms. Material and Methods The alloy used in this study contained about 71 pct Fe and 29 pct Ni. The complete analysis was 29.5 ± 0.2 pct Ni, 0.036 pct C, 0.02 pct N, 0.19 pct Mn, 0.09 pct Si, 0.008 pct P, and 0.006 pct S. The amount of isothermal transformation was determined by electrical resistance measurements using a Kelvin double bridge. The specimens were in the form of rods 1/16 in. diam x 4 in. long. Aus-tenitizing was performed at 1095°C for % hr either in a pre-purified nitrogen atmosphere or in an evacuated Vycor tube, followed by oil quenching to room temperature. After this treatment, the samples were completely austenitic, and the transformation studies were conducted at subatmospheric tempera- tures. Lineal analysis and X-ray determinations of retained austenite were used to calibrate the electrical resistance changes in terms of the percentage of martensite. The martensite range curve for this alloy is given in Fig. 9 of ref. 6. The M, temperature occurs at about -18°C (255°K). Reaction-Path Theory The nucleation and growth description of the martensitic transformation that occurs isothermally has already been given by Kurdjumow.','2 However, no comparable treatment exists using the reaction-path concept." Consequently this section presents the reaction-path description of the isothermal mode of the martensitic transformation. According to the latter theory, there is a reaction path (a strain) which describes the relative motion of the atoms during their transference from the austenitic to the martensitic state. The possibility exists, therefore, that the nucleation of a martensitic plate is accomplished by an embryo that comprises a state intermediate between that of austenite and martensite. This state may be attained within a finite volume by means of a homogeneous strain of the austenitic matrix. There is a free-energy barrier (F.) along the reaction path, corresponding to a critical strain in a critical volume. When activation is achieved, a spontaneous increase in strain and volume of the embryo takes place to generate the full-size martensitic plate. This mode of nucleation is to be distinguished from the more conventional mode involving embryos of the martensitic phase that merely grow in size by an interface motion. There are two ways whereby embryos in the austenitic phase can achieve the critical state of strain for isothermal nucleation: 1—through the formation of internal strains by plastic deformation or by stress; and 2—through thermal fluctuations, preferably superimposed upon existing internal strains. The activation free energy F,, must be supplied either mechanically by internal strains or thermally by energy fluctuations, or by a combination of both.

Jan 1, 1953

Abadilla, Quirico A. Catanawan, Tayabas, P I '20 Abbey, Robert Graham, District Mgr., The W. W. Sly Mfg. Co, 50 Church St, New York, N. Y. '21 Abbott,-A. N., Mines Supt, Mazapil Copper Co., Ltd .. Concepcion del Oro, Zac., Mexico. '23 Abbott, Clarence E., Mgr, Mines & Quarries, Tenn. Coal, Iron & R R Co. 1242 Brown Marx Bldg, Birmingham, Ala. '04 Abbott, Louis Benjamin, Chief Engr, Consolidation Coal Co, Elkhorn Div . Jenkins, Ky. '15 Abeel, George H., Jr., Cons Min Engr... . Box 427, Santa Monica, Cal. '18 Abel, Albert E., Asst. to Pres., Valley Mould & Iron Corp Hubbard, Ohio. '19 Abel, Raymond L., Asst. Prof., Dept. of Pet. Refin , Univ. of Pittsburgh Pittsburgh, Pa. '28 Abernathy, George Elmer, Prof. of Geol. & Min., Kansas State Teachers College. Pittsburg, Kans '20 ||Abernethy, D. Carl, Jr. Min. Engr., Hudson Coal Co . Scranton, Pa '27 Abey, Hiroshi, Min. & Met. Engr., Min. & Met. Dept, The Higher Technical School, Osaka, Japan. '17 Aborn, Robert H., Instructor in Met, Harvard University Cambridge, Mass. '19 Abozeid, Mahmood, Pet. Production Engr., Marland Oil Co Ponca City, Okla. '20 Abraham, Arthur W., Geol, Richfield Oil Co. Box 788, Bakeisfield, Cal. '20 Abraham, W. E. V., Member, Geol Staff of Burmah Oil Co, Ltd Nyaunghla. Upper Burma, India. '23

Jan 1, 1923

By R. H. Harrington

THE definition of precipitation-hardening is well understood and its principles have been subjected to study for some time. However, the variation of properties with double aging, combined with strain-hardening, gives promise of new and useful phenomena. Properly to understand these distinctions, definitions of these terms are necessary. Precipitation-hardening. This reaction usually depends upon an alloy having such a composition that it consists only, or in major part, of but one phase, a solid solution, at a high temperature, so that, upon slow cooling, this solution breaks down into two phases, the solid solution and a compound. By heating the alloy to the temperature for maximum solution of the compound, quenching, and reheating to a suitable lower temperature for critical dispersion precipitation of the compound, useful properties of the alloy may be developed to a maximum. Double Aging.-Dougle aging in part is similar to the process for precipitation-hardening, consisting of heating a precipitation-hardening alloy to the solution temperature, quenching, reheating to the suitable dispersion precipitation temperature, strain-hardening, and again reheat-ing to a suitable temperature to develop certain useful properties to a maximum. The strain-hardening may be induced by two methods: (1) a rate of cooling from the first reheat may suffice to strain the solid solution lattice of the alloy; or (2) the alloy may be cold-worked to a suitable degree between the two reheats.

Jan 1, 1936

By Charles W. Goodale, William A. Akers

The treatment of silver-ores of too low a grade to justify either smelting or preliminary roasting, and yet not " free" enough to permit of raw amalgamation, has ever been a serious problem. As bearing upon it, the operations of the Combination Mining and Milling Company of Black Pine, Deer Lodge county, Montana, during the past year may not be without interest. It is not claimed that the process to be described is not susceptible of great improvement, nor is any claim of originality made for it; but its use is, as yet, not very general, and it seems to offer a means of profitably working the large class of partially-decomposed argentiferous ores which, by reason

Jan 1, 1890

By Arthur Phillips

THE normal method of preparing metallic alloys for commercial use involves the preparation of a melt containing the given components in the chosen proportions and allowing the homogeneous liquid mass to solidify in a mold of the desired form. The solidification is frequently accompanied by a segregation of the alloying elements in different parts of the casting. When the segregation is occasioned primarily by marked differences in density of the solid and liquid phases, it is termed "gravity" segregation. When the segregation conforms to a. selective freezing in harmony with the teachings of the equilibrium diagram of the alloy system-i.e., the lower melting phases are concentrated in the regions of the casting last to freeze-it is often referred to as " normal" segrega-tion. However, in many cases the lower-melting part of the system is concentrated in the parts of the casting first to freeze and the result in this case is termed "inverse" segregation. To complete the. terminology of the subject, normal segregation in a single phase is usually called "coring" and the word will be used in that sense in this paper. Inverse segregation, particularly when the liquid phase is exuded or sweated out on the surface of the casting, is sometimes called "location." Unfortunately, some ambiguity has arisen from the use of this term and it is perhaps advisable to confine its use to the dictionary definition; namely, "The separation of two phases by heat sufficient to melt one but not the other." The gravity and normal types of segregation are both well understood and to some extent are controllable by taking advantage of the most favorable cooling rate for a given casting condition. Inverse segregation has received considerable attention from several investigators- but none of the theories offered seem to account in a convincing way for the many examples of this type. The observations made in the present work on segregation in single crystals, and in some other castings, tend to support one theory of the mechanism of inverse segregation and definitely to

Jan 1, 1937

By G. B. Craig, B. Ramaswami

The temperature and strain rate dependence of the flow stress ratio and the stvain rate dependence qi the flow stress of annealed polycrystalline a zirconiur were determined over the temperature range 30 0" to 1000°K. Some evidence was found for strain aging and discontinuous flow in the temperature ranges 520" to 650°Kand650" to 760°K, respectively. The Cottvell-Stokes relationship was obtained when deformation occurred by twinning as well as slip. The flow stress ratio showed a strong dependence on temperature and strain rate above 800°K. The expevirnental evidence indicated that the rate-controllitzg mechanism for the deformation of a zirconium above 800°K was dislocation climb, and that the deformation was not thermally activated in the range 520" to 800°K. The stacking-fault energy of a zirconium was estimated to be about 250 ergs per sq cm. A knowledge of the temperature and strain rate dependence of the applied stress necessary to deform a crystalline solid is essential for understanding the thermally activated processes occurring during deformation.' Several experimental techniques have been developed for studying these processes.273 One of the techniques is the deter mi nation of the strain rate dependence of the flow stress at constant temperature. In close-packed crystals, it has often been observed that the change in stress due to a change in the strain rate varies linearly with the flow stress, (~1,' This relationship, known as the Cottre ll-Stokes law, is obeyed when deformation occurs by glide alone. However, when deformation occurs by twinning as well as glide, there is disagreement among different investigators on whether the Cottrell-Stokes law is observed. Whereas Thornton et ~1.~find departures from Cottrell-Stokes law when twinning occurs in copper, ~avis~ and sasinski? find that Cottrell-Stokes law is obeyed when deformation occurs by twinning as well as slip in cadmium and magnesium, respectively. One of the main objectives of this study is to determine whether the Cottrell-Stokes law is obeyed when deformation occurs by twinning as well as slip. The second technique that has been used extensively to study the thermally activated deformation of crystals is the determination of the ratio of the flow stresses, at identical dislocation structures and con-

Jan 1, 1968

By G. W. Gross

A commercial deposit of white kaolinite clay contained in the sandy overburden of the Cambrian Gatesburg formation in Central Pennsylvania was successfully mapped by combined SP and resistivity methods and results were checked by drilling. Resistivity minima in the range between roughly 2000 and 3500 ohm-meters coupled with second-order SP maxima of 50-60 mV contrast were found to characterize commercial white kaolinite clay beneath not more than 30-40 ft. of sandy overburden in the area stdied. This investigation supports the hypothesis, established previously, that certain SP phenomena may reasonably be ascribed to diffusion and membrane potentials produced by interaction of clay lenses, sandy matrix, and ground waters. The success of this test proves that this prospecting technique can assist in locating clay deposits in sandy overburden derived from the weathering of sandstones and carbonate rocks such as the Cambrian formations of Central Pennsylvania. In a recent paper, Gross and Moore (1959) described broad self-potential minima above the outcrops of the Cambrian Gatesburg formation. These "first-order" SP anomalies, of 220-350 mV contrast (Figure 7), are related to the peculiar sandy residual soil covering the Gatesburg formation. Small positive ("second-order") peaks of 50-60 mV contrast are superposed on the bottom or flanks of the first-order troughs. They appear to be related to lenses and layers of kaolinite clays within the sandy Gatesburg overburden. Both first-order and second-order anomalies show a characteristic inverse relationship with apparent resistivity profiles in most cases. An explanation in terns of liquid-junction and shale potentials was advanced. According to this working hypothesis, shale potentials are generated: 1) at the contact of the sandy Gatesburg overburden with the more argillaceous soils of surrounding formations; 2) at the boundary of clay lenses contained in the sandy matrix of that overburden. Concentration gradients between interstitial infiltration waters and perched water tables within the Gatesburg overburden are believed to give rise to the liquid-junction potentials. In order to test this hypothesis further, a detailed study was carried out of a second-order positive anomaly on the property of the Woodbury Clay Co. at Mines (Blair County, Pa., Hollidaysburg folio of the U.S. Geological Survey). A second aim was to establish if combined SP and resistivity surveys are suitable as a practical method for delimiting favorable areas in which commercial kaolinite clay de~osits may be found by drilling. Drilling control was provided by the Woodbury Clay Co. PROCEDURES Instrumentation used for SP measurements was the same as described in the paper mentioned. For resistivity surveys, a direct-current voltmeter-ammeter device built by Georator Gorp. of Manassas (Va.) was used in combination with non-polarizing electrodes from the same manufacturer. Power was supplied by one to six 45-volt, heavy-duty B-batteries

Jan 1, 1961

By Herbert Hoover

THE time has arrived in our national development when we must have- a definite national- program in the development of our great engineering problems. Our rail and water transport, our water supplies for irrigation, our reclamation, the provision of future' fuel resources, the development and distribution of electrical power, all 'cry out for some broad-visioned national guidance. We must create a national engineering sense of provision for the nation as a whole. If we are to develop this national sense of engineering wand its relations to our great human problems, it must receive the advocacy of such institutions as this. We, together with our sister engineering societies, represent the engineers of the United States. It is our duty as citizens to give voice to those critical matters of national policy which our daily contact with this, the fundamentally constructive profession, illuminates to us. Just as our medical associations voice the necessity of -safeguards to national health; as the bar associations of safeguards to our judiciary, so the engineers should exert themselves in our national engineering policies. We have none; but we need some, or the next generation will face a lower instead of a higher standard of living than ours.

Jan 1, 1920

By R. E. Wade

THE Butte, Anaconda & Pacific electrification is of peculiar interest, in an incidental way, to the entire mining fraternity, and especially the engineering branch, not only in this great Northwest country but throughout the entire Western mining country, which is rich in minerals and water power. It is probably fair to say that the prime object of mining and smelting engineering is to reduce the cost of production, and in the case in hand the relative location of mines and smelter brings the cost of transportation of ore to the front. While some might assign this item to the railway people, it is inseparably a part and parcel of the general scheme of the production of metal from the ore. In considering the electrification of the B., A. &. P. railway the mining and smelting engineer, above all, wants to know what saving will be effected by the change in motive power. Unfortunately the new power has been in use during a very limited period and on the Smelter Hill section of the road only, and no reliable data, from actual service conditions, can be obtained until the entire electrified section has been in service for a reasonable length of time. Any remarks on this subject at the present time, therefore, must of necessity be general in nature and more or less descriptive. The railway, electrical and mining worlds and the country in general are indebted to the B., A. & P. railway for the pioneer work it is now doing, as it undoubtedly marks the beginning of the electrification, within the comparatively near future, of all transcontinental roads between the Missouri river and the Pacific coast. Together with this goes the development of an untold wealth in water power and all natural resources within the same territory. For the first time in the history of electric railway work, in this country, direct current at a potential of 2,400 volts is being used. With this potential there is a great saving in transmission of energy to the locomotives and there are only two substations, one at. either end and 26 miles apart, for supplying the power for the movement of trains of heavy tonnage over the main line and for switching movements at terminal and intermediate yards, and comparatively little feeder copper is required.

Jan 11, 1913

By Henry Mulryan

THE largest and purest known deposit of diatomite is being actively mined and processed 3 ½ miles south of Lompoc, Santa Barbara County, Calif., by the Johns-Manville Products Corporation. The workings FIG. 1-LOCATION OF DIATOMITE DEPOSIT AT LOMPOC. cover 4000 acres, the depth of economically recoverable diatomite being 1000 ft. (Fig. 1). Lompoc, a community of 2500 population, is situated in the Santa Ynez River Valley 10 miles inland from the Pacific Ocean. It is 44 miles

Jan 1, 1936

By Henry D. Hibbard

FoR the purpose of this paper all steels will be divided into two divisions: effervescing and non-effervescing. This classification must be borne in mind as many statements true of one class are not true of the other. Effervescing steels are those that effervesce in the molds, evolving large volumes of gases, which, in escaping, throw up a spray of molten particles of steel and give the molten metal in the mold a rapid stirring or churning motion until it freezes, or, at least, becomes pasty. This effervescing is intended and proper. The non-effervescing steels, which are more or less completely killed, should not evolve any gas in the molds. Many years ago the writer proposed to call the two classes of steels evolution and solution steels, depending on whether the gases in the molds are evolved or kept in solution, but the present designations seem to be better. In America, at least, effervescing steels are in a class by themselves and include steels made for boiler, tank, and ship plates, steel pipe, soft steel wire, wire nails, soft machincry, and structural steels. These are all low-carbon steels with less than 0.40 per cent. carbon. Low-carbon steels that do not effervesce but are killed are also made; these are put into ingots and castings but they are outside the limits of this paper. Effervescing steel is cast into square or slab molds, either top or bottom poured. Most of the effervescing steel is made in the basic open-hearth furnace, though much is made by the acid Bessemer process and a little is made in the acid open-hearth. It is not made by the crucible or electric-furnace process, in which the volume of gas required cannot be produced in the steel and evolved from it in the mold to give the effervescence desired. Any steel ingot, when teeming is finished, is of a certain size or volume. Leaving out of consideration for the moment the lessening of the over-all dimensions of the ingot through contraction due to loss of heat, the ingot may be placed in one of three classes: It may settle, losing in volume; it may stand, that is, remain constant in volume; it may rise, that is, increase in volume. Into which class an ingot will fall depends on the gases of the steel,

Jan 1, 1920

By J. K. Kerver, J. S. Osoba, J. G. Richardson, J. A. Hafford

A detailed study of a number of methods of relative permea-abilitv measurement has been made in a search for the tech-niqrle most suited to routine analysis of cores taken from reservoir rock. It has been found from tests run on the same samples of core material by a number of techniques that the Penn State, Hassler, Hafford, and dispersed feed techniques all yield results which are felt to be reliable. Conditions under which the faster single core dynamic technique may be used are described. Further work on the calculation of relative permeabilities to oil from data obtained by the gas drive method is needed before this latter rapid method can be utilized. Correlations between theoretical studies and experimental results have been obtained in studies of the boundary effect. pressure distribution in two-phase flow, and gas expansion effects. Previous conclusions that the effects of the outflow boundary could be made negligibly small have been substantiated. Results of experimentally determined oil and gas pressure distributions along a core sample during flow are presented. Further studies of the effects of rate of flow in the measurement of relative permeability-saturation relations have shown that results are independent of the rate of flow as long as the flow rate is below the point where inertial effects commence. An analysis of the effects of a severalfold expansion of gas along the flow path indicates that while saturation gradients are induced in the test sample, the errors caused by this phenomenon in relative permeability measurements are small. INTRODUCTION Many pages of literature have been devoted to pointing out the need for relative permeability-saturation relations in reservoir engineering. One of the most attractive ways of obtaining this information is by the analysis of samples of core material taken from the formation in question, and again literature has described man); methods for obtaining these data. It is the purpose of this paper to present the work that has been done in the study of some of these published methods together with some other methods that have been recently developed in this laboratory. Also, a study of some of the factors that influence the laburatory determination of relative permeability-saturation relations is presented. FACTORS WHICH AFFECT LABORATORY STUDY OF FLUID FLOW THROUGH RESERVOIR ROCK To determine relative permeability-saturation relations of samples of reservoir rock in the laboratory, it is important to know what factors affect these measurements in order that the magnitude of these effects can be ascertained and steps then can be taken to eliminate or, in some cases, to minimize them. The factors that have been investigated are the boundary effect, the effect of gas expansion. and the rate effect. Boundary Effect In laboratory experiments in which two immiscible fluids are flowed through a porous medium, there exists a discontinuity of capillary properties at the outflow face. This discontinuity exists became the fluids pass from a region of finite capillary pressure in the sample to a region of zero capillary pressure in an open receiving vessel. The capillary forces existing in the core caupe the rock to tend to retain

Jan 1, 1952

By E. S. Machlin, S. Weing

GRAIN boundary stress relaxation has been the subject of several investigations in recent years, but as yet the phenomenon is not well understood. One of the major difficulties has been the lack of a sufficient amount of data with which to evaluate any proposed mechanism. Little information is available on the effect of small amounts of substitutional solutes on grain boundary stress relaxation. It is with this important phase of the problem that this investigation is concerned. The influence of substitutional solutes on grain boundary stress relaxation has been recently investigated in copper by Pearson: and in aluminum by Dorn et al.' Pearson studied the effect of zinc, gallium, germanium, and arsenic on the relaxation peak of OFHC copper.* The pure OFHC copper decreased the peak intensity and a second peak appeared at a higher temperature. This latter peak was termed the alloy grain boundary peak. At the lowest binary concentration studied, approximately 1 atomic pct, the primary peak was almost completely obliterated. Pearson found that the activation energy calculated from the alloy grain boundary peak for all solutes, irrespective of the concentration, was 44,000 cal per mol. Pearson concluded that the increase in activation energy from 33 to 44 kcal per mol is not continuous but abruptly changes from the lower to the higher value. As no attempt was made to investigate the intermediate range of concentration and hence calculate the possible variation of the activation energy for the initial grain boundary peak, this conclusion is hardly valid. In contrast to these results, Dorn et al. studied the effect of zinc, silver, copper, germanium, and magnesium on the grain boundary stress relaxation of aluminum. No change in the energy of activation was observed for binary alloys of the flrst four solutes, but a linear increase was found for increasing concentration of magnesium. Saturation was not found up to the maximum of 1.6 atomic pct. The energies of activation were obtained by plotting the horizontal displacement of the dynamic modulus curve vs temperature for two vibrational frequencies. As the modulus is proportional to the square of the frequency, this requires the measurement of the torsional frequency over a range of temperature. However, the technique does not lead to an unambiguous interpretation of the grain boundary

Jan 1, 1958