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By J. K. Stanley

Iron-cobalt alloys in the range of 35-50 pct cobalt are of interest in the electrical industry because they possess the highest magnetic saturation of any magnetic material known. l1,2The magnetic saturation induction of the 35 pct alloy is 24,200 gausses, compared to 21,600 for pure iron (Fig I). This difference is significant in electrical apparatus, whcre weight or space is at a premium. Saturation values higher than that for iron can be attained up to about 70 pct CO hut economics restrict the use to as low a cobalt content as possible without sacrifice of saturation. Fig 2 shows the iron-cobalt equilibrium diagram. Up to the present time, two factors have retarded the use of iron-cobalt alloys in the electrical industry for magnetic purposes.? One is the high cost of cobalt ($I.50 per pound) and the other ig the inherent brittleness of the binary iron-cobalt alloys. Straight iron-cobalt alloys up to 25 pct cobalt are ductile and easy to process to thin sheet or strip by conventional methods of hot and cold rolling, but the alloys containing higher percentages of cobalt, including those for which the saturation magnetization is a maximum (35 to 40 pct), are increasingly brittle with increasing cobalt, at least up to 50 pct, and are consequently difficult to process, either hot or cold. Work by White and Rah13 indicated that iron-cobalt alloys could be made ductile by alloying with vanadium, and after quenching the alloys (vanadium up to about 4 pct) were found to he colt1 rollable to very thin gauges. With this as a background, we resumed our work on these alloys with the objective of developing methods for economical commercial production of wide strip. For this purpose we have concentrated on the 35 pct alloy in order to obtain the highest possible saturation value. Experiments were carried out on many alloy additions to the iron-cobalt alloys and on the response of these compositions to heat treatments. This work finally culminated in a commercially producible iron-cobalt alloy which has been named Hiperco.* Materials StudIEd and Procedur' Binary alloys of iron and cobalt in the range of 35 pct cobalt are difficult to hot work (by forging or rolling) without such additions as C, Mn, Si, V, Cr, Mo, W Or perhaps others. Another beneficial effect of such additions is that they increase to a greater or less extent the strangely low electrical resistivity of these alloys about 10 microohms per cm3

Jan 1, 1948

By James K. Stanley

IRON-COBALT alloys in the range of 35-50 pct cobalt are of interest in the electrical industry because they possess the highest magnetic saturation of any magnetic material known.1,2 The magnetic saturation induction of the 35 pct alloy is 24,200 gausses, compared to 21,600 for pure iron (Fig I). This difference is significant in electrical apparatus, where weight or space is at a premium. Saturation values higher than that for iron can be attained up to about 70 pct Co but economics restrict the use to as low a cobalt content as possible without sacrifice of saturation. Fig 2 shows the iron-cobalt equilibrium diagram. Up to the present time, two factors have retarded the use of iron-cobalt alloys in the electrical industry for magnetic purposes.† One is the high cost of cobalt ($1.50 per pound) and the other is the inherent brittleness of the binary iron-cobalt alloys. Straight iron-cobalt alloys up to 25 pct cobalt are ductile and easy to process to thin sheet or strip by conventional methods of hot and cold rolling, but the alloys containing higher percentages of cobalt, including those for which the saturation magnetization is a maximum (35 to 40 pct), are increasingly brittle with increasing cobalt, at least up to 50 pct, and are consequently difficult to process, either hot or cold. Work by White and Wah13 indicated that iron-cobalt alloys could be made ductile by alloying with vanadium, and after quenching the alloys (vanadium up to about 4 pct) were found to be cold rollable to very thin gauges. With this as a background, we resumed our work on these alloys with the objective of developing methods for economical commercial production of wide strip. For this purpose we have concentrated on the 35 pct alloy in order to obtain the highest possible saturation value. Experiments were carried out on many alloy additions to the iron-cobalt alloys and on the response of these compositions to heat treatments. This work finally culminated in a commercially producible iron-cobalt alloy which has been named Hiperco. * MATERIALS STUDIED AND PROCEDURE Binary alloys of iron and cobalt in the range of 35 pct cobalt are difficult to hot work (by forging or rolling) without such additions as C, Mn, Si, V, Cr, Mo, W or perhaps others. Another beneficial effect of such additions is that they in-crease to a greater or less extent the strangely low electrical resistivity of these alloys (about 10 microohms per cm3

Jan 1, 1947

By J. K. Stanley

Iron-cobalt alloys in the range of 35-50 pct cobalt are of interest in the electrical industry because they possess the highest magnetic saturation of any magnetic material known. l1,2The magnetic saturation induction of the 35 pct alloy is 24,200 gausses, compared to 21,600 for pure iron (Fig I). This difference is significant in electrical apparatus, whcre weight or space is at a premium. Saturation values higher than that for iron can be attained up to about 70 pct CO hut economics restrict the use to as low a cobalt content as possible without sacrifice of saturation. Fig 2 shows the iron-cobalt equilibrium diagram. Up to the present time, two factors have retarded the use of iron-cobalt alloys in the electrical industry for magnetic purposes.? One is the high cost of cobalt ($I.50 per pound) and the other ig the inherent brittleness of the binary iron-cobalt alloys. Straight iron-cobalt alloys up to 25 pct cobalt are ductile and easy to process to thin sheet or strip by conventional methods of hot and cold rolling, but the alloys containing higher percentages of cobalt, including those for which the saturation magnetization is a maximum (35 to 40 pct), are increasingly brittle with increasing cobalt, at least up to 50 pct, and are consequently difficult to process, either hot or cold. Work by White and Rah13 indicated that iron-cobalt alloys could be made ductile by alloying with vanadium, and after quenching the alloys (vanadium up to about 4 pct) were found to he colt1 rollable to very thin gauges. With this as a background, we resumed our work on these alloys with the objective of developing methods for economical commercial production of wide strip. For this purpose we have concentrated on the 35 pct alloy in order to obtain the highest possible saturation value. Experiments were carried out on many alloy additions to the iron-cobalt alloys and on the response of these compositions to heat treatments. This work finally culminated in a commercially producible iron-cobalt alloy which has been named Hiperco.* Materials StudIEd and Procedur' Binary alloys of iron and cobalt in the range of 35 pct cobalt are difficult to hot work (by forging or rolling) without such additions as C, Mn, Si, V, Cr, Mo, W Or perhaps others. Another beneficial effect of such additions is that they increase to a greater or less extent the strangely low electrical resistivity of these alloys about 10 microohms per cm3

Jan 1, 1948

By C. W. Gibbs, E. K. Parks

In 1929 the Standard Oil Company of California commenced the development of a device for obtaining temperatures and pressures in flowing and shut-in wells and of suitable running equipment for such a recorder. Although simple in principle, the recorder has required much experimental work in its development. The various problems have now been solved to such an extent that it is believed that the apparatus affords a sturdy and reliable means for obtaining information regarding depth pressures,—apparatus that may be turned over to a well gang for routine operation. As an example of the rough usage the device will withstand a recent incident may be cited. Owing to failure of the lowering line at the conclusion of a run a recorder was dropped some 6300 ft. through 2 1/2-in. tubing filled with gassy oil. The device was fished out undamaged and with the pressure record intact, although the instrument had been subjected to a pressure greater than 2300 lb. per sq. in. for some 24 hr. after impact at bottom. Description of Recorder The instrument is of the continuous recording loaded spring type (Fig. I). Temperature is not recorded continuously but is obtained by maximum recording thermometers in an auxiliary thermometer well. The entire instrument assembly, from bottom of the recorder to top of the socket, is 6 1/2 ft. long and weighs less than 25 lb. The maximum outside diameter of the recorder shell is 1 1/4in., and all attachments need be no larger. This permits lowering the device inside 2-in. tubing. The operating principle is simple. The well pressure acts upon a piston A resisted by the extension of spring B. The spring deflection is recorded by a stylus C upon paper within the recording drum D. Springs.—To improve accuracy at lower maximum well pressures five interchangeable spring assemblies are used. These have maximum pressure ranges of from 250 to 5000 lb. per sq. in. Piston diameter is the same in all cases, and each spring is designed for a deflection of about 5 in. for maximum pressure loading. A complete spring assembly there-

Jan 1, 1934

By John M. Bostwick, James C. Bradbury

Bitumen is a general term for a group of materials composed of mixtures of hydrocarbons that are fusible and soluble in carbon disulfide. Included in the group are petroleum, asphalts, asphaltites, and mineral waxes. Asphalt is a dark-colored, cementitious solid or semisolid, which generally softens on heating and resumes a more viscous or solid state when cooled. It is found in native form in fissures and pore spaces in rocks and as lakes. It is also obtained from the residues produced in petroleum refining. Asphaltites are black, naturally occurring solid bitumens. They are generally shiny and break with a conchoidal fracture. Common asphaltites are gilsonite (uintahite), grahamite, and glance pitch. Mineral waxes are solid or semisolid, relatively nonvolatile bitumens of various colors, having an unctuous feel and waxy luster, Of the native waxes, ozokerite is the best known. Montan wax is also classed as a natural wax, although it never occurs in the pure state and must be extracted from lignite or cannel coal (Ladoo, 1920). Mineral waxes may also be obtained by pyroprocessing of petroleum, lignite, and peat. Pyrobitumens are dark-colored, solid hydrocarbons that are infusible and relatively insoluble in carbon disulfide. They are so-called because they will yield liquid and gaseous hydrocarbons only when heated. Asphaltic pyrobitumens are defined as "substantially free of oxygenated bodies" and include wurtzilite (elaterite), albertite, and impsonite (Thrush, 1968). Nonasphaltic pyrobitumens contain oxygenated bodies; examples are coal and peat. The nonasphaltic type will not be discussed further. Petroleum Asphalts Asphalts refined from crude petroleum have almost completely replaced the native types. Refineries can produce asphalts in every desirable grade more economically and in greater quantity than the native types and with a variety of properties that meet the requirements of the various manufacturers using them. For all practical purposes, it is estimated that more than 95% of the asphalts consumed in the United States are refined from crude petroleum (private communication). Native Asphalts Native asphalts are dark brown or black, semisolid or solid substances that, in theory, formed by slow, natural fractionation of crude petroleum at or near the surface of the earth (Goulston, 1938). They are colloidal systems of high molecular weight components dispersed in a medium consisting of low molecular weight components (Pracy, 1954). Native asphalts may occur as lakes, as impregnations of rock (rock asphalt) or as deposits consisting of mixtures of natural asphalt and mineral matter in various proportions (Stern, 1960). Practical use of native asphalt dates to about 3000 B.C. It was mined from surface pits or lakes and used, then as now, for masonry mortar, waterproofing aqueducts and tunnels, binders for road construction, and as an article of commerce (Miller, 1938). Generally the native asphalts find little commercial use today except where they are geographically abundant, easily mined and transported, or have specific or special application. Petroleum-refined asphalt is produced by unusually economical techniques and is much less costly to use. The largest and best known of the lake deposits is that on the Island of Trinidad, where the lake covers an area of 114 acres and is 285 ft deep at its center (Stem, 1960). The lake asphalt is refined by heating to evaporate in-

Jan 1, 1983

By Robert L. Slobod

In much of the work reported in the literature on long cores. true connate water value, probably have not been obtained because of insufficient flow of 011 to attain equilibrium. A -.satisfactory method for establishing connate water in long cores has been developed in which oil flow is maintained until no additiona1 water is displaced. INTRODUCTION Long cores have been used by sev-erals investigators in an effort to evaluate the efficiency of oil recovery for various producing schemes. The effects of many variables such as rate of displacement. pressure drop, volume of displacing medium, gas-oil ratio, inter-facial tension, and others have been investigated, and the merits of gas drive have been compared with water drive. In the older experiments no connate water was used. but in the more recent stndies the philosophy of the experiment calls for a core containing oil and connate water (irreducible water) as the starting point of the experiment. The method generally used to establish this condition in long cores involves dynamic' displacement wherein one or more phases are forced through the core. flow being maintained at a constant rate or at a constant pressure until a steady state is reached wherein there is no change of saturation with time. It is one purpose of this paper to point out that in much of the work reported in the literature true connate water values probably have not been obtained. The reason for this failure is pointed out. and a method for obtaining more reliable connate water values on long cores is presented. It is impossible at this time to completely evaluate the effect on the conclusions in the earlier papers resulting from the failure to obtain true connate water in the long cores, but some data are presented which indicate that serious errors may he present in many cases. MATERIALS AND APPARATUS Cores cut front outcrop sandstones (Strawn. Torpedo, and Elgin sandstones) with permeabilities of the order of 300 md were used. The major experiments were made with a core 18-in. long and 2-in. in diameter. Cores of the same diameter but only 12-in. long were used in a few tests? and in some work a core I-in. in diameter and 11-in. long was used. These materials were all somewhat bentonitic. 'To reduce the effect of such constituents, one of the cores (Torpedo No. 10) on which the most work was performed was acid extracted at the start of the experiment. Brine containing 50,000 ppm chloride and naphtha (Stoddard's Solvent) were used as the water and oil phases, respectively. The core was mounted in a rubber sleeve which forms the inner lining of a brass cylinder. In this arrangement2 the rubber sleeve is forced against the core by applying pressure to water in the annular space between the rubber sleeve and the brass cylinder wall. The core is therefore sealed in rubber so that all fluids introduced at the input end of the core flow through the core. With this equipment the core may be easily removed for inspection and analysis. Also, other cores may be introduced for study with no extra time for preparation such as is required when plastic mounting is used. When pressure or conductivity measurements are desired at intermediate points along tile length of the core, the brass cylinder comprising the outer jacket of the core holder is cut into section, of the desired length. Each section is then made up as an individual unit with its own rubber sleeve (see Fig. 1). The individual units are then butted up against a ring of plastic or other insulating material which carries an electrical contact for resistivity measurements and an opening which can be used for the measurements of fluid pressures. The individual units are forced tightly against the plastic ring separators and held in place with several tie rods. Inlet and outlet end butts of the same diameter as the core and several inches in length are provided to control the introduction and withdrawal of fluids and to complete the arrangement for sealing the core within the rubber sleeve. Fluid flow is maintained either by applying pressure to the liquid confined in a reservoir or by the use of a gear pump. The latter is preferable where continuous flow at a moderate rate over a long time interval is desired since a small volume of liquid can be readily recirculated using filters to prevent plugging of the core. EXPERIMENTAL The oven-dried core is weighed and is then completely saturated with brine

Jan 1, 1950

By K. E. Starling

Phase equilibria data were used to develop an equation-of-state correlation for complex hydrocarbon mixtures, thereby circumventing difficulties associated with use of pressure-volume-temperature data. Equilibrium phase data for two condensate reservoir fluids were used to determine equation-of-state parameters for hydrocarbons as heavy as C22H46 in a modified form of the Benedict-Webb-Rubin equation of state. Comparative tests of K-values from the resultant correlation were made with data for condensate reservoir, separator and gas plant absorber mixtures. Generally, for temperatures above OF and computed liquid densities below 0.55 Ib-mole/cu ft, the modified BIVR equation predicted K-values in close agreement with the experimental data. INTRODUCTION Accurate predictions of thermodynamic behavior for complex hydrocarbon mixtures are necessary for many calculations in the petroleum industry. Because of the relatively high cost of extensive experimental data, many correlations for prediction of phase behavior have been developed. Some of these, such as the correlation of K-values presented in the NGAA Equilibrium Ratio Data Book, are totally empirical.l Others, such as the Benedict-Webb-Rubin (BWR) equation-of-state method, are semitheoretical.2-4 Unfortunately, published correlation methods often do not accurately predict the phase behavior of complex hydrocarbon mixtures, principally because of inadequate representation of the effects of components heavier than decane. This paper presents a new approach to this problem in which basic equation-of-state relations including heavy hydrocarbon effects are applied. Equilibrium phase data for two condensate reservoir fluids containing hydrocarbons as heavy as C22H46 are used to correlate component K-values. The BWR equation was chosen as the prototype equation of state for this study because of its proven capability for accurately predicting phase behavior and thermodynamic properties of light - hydrocarbon mixtures? Research was directed toward development of BWR parameters for the heavy hydrocarbons and modifications of the mathematical form of the BWR equation for application to complex hydrocarbon mixtures. The new equation-of-state approach presented differs considerably from previous methods in that phase equilibria rather than PVT data are used for determination of equation-of-state parameters. It is an explicit approach since the parameters are determined directly from mixture data. As such, it does not encounter problems inherent in the implicit method used by Benedict, Webb and Rubin 2-4 and numerous other investigators—one in which mixture parameters were postulated to be functions of the pure component parameters. The pure component BWR parameters, in turn, were determined from experimental PVT data. This method has been limited to mixtures containing components lighter than decane because of lack of vapor phase PVT data. Studies have been reported in which BWR parameters have been determined explicitly from PVT data for binary mixtures.6-8 However, since small concentrations of heavier components have only a minor effect on PVT behavior, it is doubtful that these explicit methods would yield useful results for condensate systems. Ellington and Eakin9 have shown that the accuracy of K-values predicted by an equation of state developed from mixture PVT data probably would be more than an order of magnitude lower than the accuracy of the PVT data. On the other hand, an equation of state utilizing parameters developed from phase equilibria data should predict K-values with accuracy comparable to the accuracy of the experimental phase compositions. This work applies this explicit approach with the objective of improving hydrocarbon mixture phase behavior predictions. Results are evaluated by comparing predicted and experimental K-values at reservoir, separator and gas plant

Jan 1, 1967

By J. F. Poland

B. C. Burgess-—Prior to hearing this paper presented at the San Francisco meeting, I travelled by car from Yuma, Ariz., across south-central California and up through the San Joaquin Valley. After hearing the paper I returned by the coast route to San Diego then along the Mexican border to Yuma. The striking feature of these trips, related to this paper, was the dry river and creek beds at a time of year not the dry season. Contrasted with this was the wasteful use of water in irrigation canals and laterals. Poland says "at least 90 pct of the ground water pumped is used for irrigation." That being the case, it would appear that first consideration should be given to conservation of this use. Probably a small part of this is actually reaching the plants. Some measure of this loss between pump and crops would be revealing. Methods that might be employed to reduce this loss are pipe lines and spraying of some crops such as the banana planters are using in Central America. Another idea which might be investigated is to line canals and ditches with some water-repelling mineral like pyro-phyllite. Perhaps a comparatively thin sprayed-on

Jan 1, 1951

By J. F. Poland

B. C. Burgess-—Prior to hearing this paper presented at the San Francisco meeting, I travelled by car from Yuma, Ariz., across south-central California and up through the San Joaquin Valley. After hearing the paper I returned by the coast route to San Diego then along the Mexican border to Yuma. The striking feature of these trips, related to this paper, was the dry river and creek beds at a time of year not the dry season. Contrasted with this was the wasteful use of water in irrigation canals and laterals. Poland says "at least 90 pct of the ground water pumped is used for irrigation." That being the case, it would appear that first consideration should be given to conservation of this use. Probably a small part of this is actually reaching the plants. Some measure of this loss between pump and crops would be revealing. Methods that might be employed to reduce this loss are pipe lines and spraying of some crops such as the banana planters are using in Central America. Another idea which might be investigated is to line canals and ditches with some water-repelling mineral like pyro-phyllite. Perhaps a comparatively thin sprayed-on

Jan 1, 1951

By W. D. Robertson, E. G. Grenier, V. F. Nole

The electrical, mechanical, and corrosion cracking properties of an age-hardenable Cu-Ni-Si alloy have been studied over a range of time, temperature, and deformation states for the purpose of determining the relationship between the properties and the structural state. The precifitate has been identi3ed as and the sites of preferred precipitation have been located by electron microscope studies of the structures developed by various combinations of heat treatment and plastic deformation. An extreme form of deformation banding has been observed in the aged alloy that results in high strain concentration in bands lying parallel to {111} planes. These bands are the structural paths along which transcrys-talline cracks propagate in the deformed alloy. The observations provide a basis for a general mechanism of transgranu-lar corrosion cracking of face-centered cubic alloys in terms of stacking fault probability. AMONG the age-hardening copper alloys the copper-nickel-silicon (Silnic Bronze) type is outstanding in exhibiting a high strength combined with a considerable capacity for cold working, a relatively high conductivity, and a low to negligible susceptibility to stress corrosion cracking. It is not a new alloy and it has been the subject of a number of investigations,1-5 which were made primarily to establish practical composition and heat treatment limits. The structural characteristics of the aging processes in this alloy have not previously been studied in detail. This particular investigation was undertaken to explore, in detail, and over a wide range of conditions, the properties obtainable by various combinations of working and heat treatment and to correlate structural changes with the observed mechanical, electrical and corrosion properties. MATERIAL AND PROCESSING Eight different commercial heats of the alloy were made and used in the investigation. The range of composition among the eight heats is shown in Table I. Billets, 8 by 24 in., were cast into water-cooled molds, extruded to 1.687-in. rod, and quenched in water after extrusion. Extruded material was rod rolled to 0.750 in., annealed at 1450° F for 2.5 hr, and quenched in water. Subsequent working operations were performed by tandem rolling to various sizes depending on the degree of reduction required. Final cold-working operations were performed by drawing to a uniform size of 0.187 in. diam and straightening by a roller straightening machine (Lewis). The combinations of heat treatment, working and aging that were investigated are summarized in Table 11; the various treatments were performed in the order given in each row of the table, and they will be subsequently identified by the symbols shown in the first column. SOLUTION TREATMENT All material investigated in the cold-worked condition, or cold worked prior to aging, was solution

Jan 1, 1962

By H. S. McKnight

One phase of Canada's rapid development in mining and metallurgy during the past few years has been the creation of Canadian Copper Refiners Ltd., and the establishment of its modern electrolytic copper refinery at Montreal East, Quebec. Canadian Copper Refiners Ltd. is made up of three well-known metal firms whose combined activities cover the entire industry from the mine to the market. They are Noranda Mines Ltd., Toronto, Nichols Copper Co., New York, and British Metal Corporation, Ltd., London. Noranda Mines is the principal owner and provides the greater part of the raw material received by the refinery for treatment. Nichols Copper Co. designed and built the plant and is operating it under contract. British Metal Corporation acts as sales agent and markets the refinery's products. Montreal East was chosen as the site of the new refinery only after a careful survey had been made of the entire eastern part of Canada. The location chosen offers many advantages, chief of which arc the relatively low costs of power, labor, fuel and bupplies, and the fact that it is situated on Montreal harbor, the nearest seaport to the points of origin of the ram materials. All incoming material is received by rail. A majority of the plant's product is exported through the port of Montreal to European markets, being handled to the docks in railroad cars. A large proportion of the product is delivered by means of an industrial railway to the adjacent rolling mill of the Canada Wire & Cable Co., Limited. The refinery was designed to treat primarily the copper produced by Noranda Mines, Ltd. and Hudson Bay Mining &. Smelting Co., Ltd., and its rated capacity is 75,000 short tons per year. A general layout of the plant is shown in Fig. 1. Its capacity can be readily doubled, as shown by the dotted lines. Figs. 2 and 3 are sections taken through the furnace department and the tank house respectively. Except for the main office and laboratory and an auxiliary building containing the stores, warehouse, change rooms, compressor room and machine shop, the entire plant is under one roof. The type of building construction consists of reinforced concrete foundations supported on concrete piles, a steel structure covered with Robertson Protected Metal siding and a 3-in.

Jan 1, 1934

By William N. Poundstone

To forecast the future of coal intelligently, one must first consider the market outlook. Coal can be used for many purposes, but currently about 25% of it goes into metallurgical coke, while 75% serves as fuel. Coal for metallurgical coke should show a modest growth for at least the next decade, primarily because of increased exports, but the important factor in the coal outlook is energy. Today, this country faces a serious shortage of energy, and its requirements are growing at an almost unbelievable rate. Last year the United States consumed 68 quadrillion Btu, or double the energy it consumed in 1950, and, if projections are correct, this figure will grow to 150 quadrillion Btu by 1990. Thus, in one working lifetime, the nation's energy consumption is expected to increase by roughly five times. The future of coal hinges on its degree of participation in meeting this energy need. The Federal Power Commission predicts that coal consumed by electric utilities will increase about 4-576 per yr, reaching 472 million tons by 1980 and 615 million tons by 1990. If this projection proves correct, 1980 consumption will be double that of last year and, even more startling, the utility industry alone will use more coal in 1990 than the entire coal industry produced in 1970. This is a tremendous increase, but in view of the projected energy growth, it is difficult to see how this country's needs can be satisfied with- out a coal contribution of this magnitude. Unless some new source such as solar energy is discovered, it must be assumed that the projected energy will come principally from the present-day sources-oil, gas, nuclear materials and coal.

Jan 1, 1971

By E. S. Machlin, A. J. McEvily

HE results of an experimental investigation by McEvily and Machlin have indicated that a strong relationship exists between the processes of cross slip and fatigue. Whenever dislocations can cross onto an intersecting plane and expand thereon, as in AgCl crystals, the usual type of S-N behavior is obtained, but when such a process is difficult, as in NaCl crystals, fatigue does not occur in its usual manner, if at all. MgO, because of its crystal structure (NaCl type) and slip systems ({110}<110>) would not be expected to fail in fatigue. However, Cornet and Gorum2 have found something akin to the usual type of fatigue behavior for MgO crystals. The purpose of this note is to attempt to resolve this apparent discrepancy. In Cornet and Gorum&apos;s work as-cleaved crystals were tested under cyclic axial loading, whereas in McEvily and Machlin&apos;s work chemically-polished crystals were tested in reversed bending. Because of the difference in specimen preparation, the major effort of the present work was directed toward comparing the behavior of as-cleaved as opposed to chemically-polished specimens. The effect of type of loading seemed less important, but a check was made on this also. Eighteen bend tests and one axial load test were made. The specimens were cleaved from Norton magnorite blocks, and measured 1 by 3/16 by 1/8 in. To avoid failures in the grips, the thickness of the bend specimens was reduced from 1/8 in. near the ends to 0.04 in. in the central portion. This reduction was from one side of the crystal only. Twelve specimens were polished in orthophosphoric acid to remove the damage due to cleavage. The other six specimens were not chemically polished so as to maintain the as-cleaved condition of the crystal faces which had not been reduced. The axial-load specimen was reduced from both faces to a thickness of

Jan 1, 1962

By C. R. Swarts

The use of compressed air or gas in oil wells for raising crude oil to the surface has, within the last year, become a dominant factor In production engineering. Previous application of this principle was largely confined to oil wells that had been pumping for a considerable length of time. In the Seminole area, the gas-air lift has been applied to wells imniediately after natural flow has ceased and in some cases while the wells were still flowing. This early application of the gas-air lift has been watchcd with intense interest by the petroleum industry, both with respect to methods of application and mechanical installations and to the effects on immediate and ultimate production. Methods of Application The Seminole pool at its inception contained sufficient gas associated with the oil to cause natural flow. As no frce gas was found in the main productive horizon, the Wilcox sand, all the gas present was dissolved in the oil, hence the natural flowing life was short, rarely lasting over 45 days. When natural flow ceased, high fluid levels were common, and as depth and crookedness of holes were obstacles to efficient pumping, the gas-air lift was used almost exclusively in raising the oil to the surface. Because of the high gravity of the oil, 41" A. P. I., and its high gasoline content, and also because of the desire to obtain production before offset wells became productive, quantity of production was the aim of the operators and a method of flow was used whereby this aim could be fulfilled. One of the outstanding features of this method consisted in flowing the wells through the annular space between the tubing and rasing. By this means a greater quantity of fluid could be handled than by flowing through the tubing of the size in ordinary use. Wells that would produce only a few hundred barrels on the pump were by this rnethod made to produce as high as 7000 bbl. on the lift. A few days or wreks of production at that rate meant a large recovery of oil. Casing of 636 in. diameter was commonly used as a production string with a 5 3/16-in. liner set on top of the oil sand. Upset tubing for irtro-

Jan 1, 1928

By Bruce T. Stanley

The concepts of ore reserve estimation at the Henderson mine are reviewed presenting a geostatistical approach and procedure as applied. Specific problems encountered are recapped and explained as to the nature and resolution thereof. The methodology and results are shown, along with an approximation of computer usage and capacities needed. The scope of the paper is to set forth an example of actual application, usage, and benefits realized from such a procedure. Local Conditions The Henderson molybdenite deposit is located in central Colorado about 69 kilometers west of Denver. The geology consists of a classic subvolcanic ryolite porphyry sequence with quartz-molybdenite mineralization occurring in an extensively fractured granite stock complex. Being assymetric and bilobate in section, the orebody measures approximately 300 meters thick and 600 meters by 1200 meters in plan. The orebody is sampled by means of underground drill holes which create an east-west fan pattern spaced roughly 60 meters apart in the north-south direction. Approximately 27,000 meters of drill hole assayed on 3.04-meter intervals were available for analysis. Recovery on the core is about 95 to 100 percent, thereby affording us with reliable data all prepared to the same standards.

Jan 1, 1977

APPROXIMATELY 90 per cent of the steel that is melted and refined in the United States and poured into ingots is made in basic open-hearth furnaces, as shown in Table 1-1. The annual ingot capacity of the steel industry reported January 1,1950, by the American Iron and Steel Institute8* was 99,040,160 tons, of which the basic open-hearth process accounted for 85,896,580 tons, 86.7 per cent of the total. The capacity of the individual furnaces varies over a wide range, a large majority falling within limits of 50 to 200 tons (Fig 1-1). Most of the units constructed [ ] since 1942 are in the larger size groups, between 175 and 225 tons capacity.

Jan 1, 1951

By ROBERT E. CROCKETT

MAGNETITE mining and milling in New York, New Jersey and Pennsylvania continued to remain comparatively inactive during 1933, owing to the low rate of output of the steel industry and also to unrestricted importation of foreign ores. However, some improvement over conditions existing in 1932 was noticeable, particularly in New Jersey, where one plant, that of the Washington mine of the Alan Wood Mining Co., at Oxford, went on full production in August. At Lyon Mountain, N. Y., the Chateaugay Ore and Iron Co. resumed mining and milling operations in October, on a reduced scale, principally to provide employment during the winter months. The Chateaugay company produces a special low-phosphorus pig iron. During the year they obtained a contract to supply their product for use in the manufacture of the suspension cables of the New. Golden Gate Bridge.

Jan 1, 1934

By Lewis A. Riley

I desire to submit, for the consideration and information of the members of the Institute, the following data, drawings, and tables, showing what I believe will be interesting information with regard to the diamond drill, and its uses in developing mineral lands. I would first say that the results given have been obtained during the past two years by means of two drilling machines belonging to the Lehigh Valley Coal Company, operating on their coal lands in the Mahanoy, Lehigh, and Wyoming regions. 1st. A tabulated statement, giving location of borings, date, progress, total cost, itemized cost per foot, etc. 2d. Section showing strata bored in Nos. 5 and 10 holes at Mt. Carmel, see Plate VI. 3d. Section showing strata bored in No. 19 hole at Hazleton, see Plate VI. 4th. Photograph and description of drill No. 2. From the first it will be seen that the total number of test-holes bored up to May 1st of this year is 24; 9 of these are in the Mahanoy region, 6 in the Lehigh region, and 10 in the Wyoming region, in all of which cores have been taken for the whole distance. The total distance bored is 9902 feet. The majority of the holes have been put down for the purpose of proving the lower veins of the coal series, and have had to encounter the harder rocks of the coal formation. Much of the distance has been through the lower conglomerates, going in some cases through the coarse egg conglomerate, the foundation of the coal deposit, and to the green sandstone and red shale which underlie it. These lower sandrocks and conglomerates are among the hardest known to geologists, and present a formidable resistance to the exploring drill. This fact must be taken into consideratiotl in comparisons of cost of drilling, and when considered will still further improve the very favorable results I am able to show in my statement of costs. In illustration, I will cite the work of one bit when boring in the upper or softer rocks of the Wyoming region, where 280 feet were obtained without resetting, while in the Lehigh and Mahanoy regions, in the lower and harder rocks, bits set with the same quality of diamonds would only bore from 3 to 20 feet before being worn out. In this connection it may

By I. N. Knapp

I Herewith present some notes on the use of Portland cement to cement in the casing, and for plugging, to exclude water from oil and gas wells, and the methods employed. I have used my best efforts to. make each step of the operation of cementing wells perfectly clear. The information is the result of actual experience and observation. The illustrations are from original drawings made especially for this paper. Portland Cement It is not necessary to discuss here the manufacture of cement. Any established brand of the slower setting Portland cements may be purchased with the confidence that it will harden, if properly used, and exclude water from and plug wells efficiently. Setting.—By the setting of cement is meant its initial change from a soft or plastic mortar to a friable solid. After the cement has become thoroughly set it is still very weak and can be readily pulverized in the fingers. Setting is thought to be effected by the crystallizing out of the silicate and the aluminate of lime, which are soluble in water in their anhydrous form. After dissolving in the water they pass to the hydrated state, in which they are insoluble, and hence are precipitated in a crystalline form. Ordinarily neat Portland cement mortar remains perfectly plastic for from 1 to 1 1/2 hr. after mixing with water at about 70" F. A higher temperature accelerates and a lower retards setting.. Hardening.—This is due to a continual crystallization of salts from solution, and to further chemical and physical changes which develop slowly, but which continue for long periods of time. Testing.—It is no more necessary for an operator to go into the scientific testing of cement to be used in a well than to so test the pipe used. He must depend for the quality of each on the tests and reliability of the manufacturer. Cement or pipe may be damaged in shipment so

Jan 1, 1915

By H. LIVINGSTONE LMAN

A GOOD DEAL of information concerning flotation has come out during the patent litigation of recent years, and the legal situation has cleared considerably, to the satisfaction of Minerals Separation, Limited. Hence, Mr. H. Livingstone Sulman, one of the originators of the successful process of that company, felt at liberty to explain, on Thursday, Nov. 20, his experience and his views in a "Contribution to the Study of Flotation," before the Institution of Mining and Metallurgy. He did not give technical details. He dealt with the physical problems, so simple, as he remarked, that he had wanted 96 pages to express his views. He presented much data, partly new and based on observations of his own, bearing upon the very complex flotation phenomena in an instructive wav and made frequent references to the valuable researches especially of Prof. Edwin Edser and Mr. Emil Hatschek.

Jan 1, 1920