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By R. A. Wagstaff

SINCE the time of the early Egyptians, the use of copper has been a boon to the life of most of the civilized world. Its use has been varied; in many connections, the art by which it attained its greatest usefulness has been lost. In this paper an endeavor will be made to take into consideration some of the many changes that have occurred during the last 40 years of copper-smelting operations. During that period the copper blast furnace has been almost forced out of existence by new methods of ore concentration-first, gravity concentration, and then flotation. These new methods of concentration introduced many new factors into the metallurgy of copper. The product was wet, it was fine and it was high grade. To overcome all these factors many changes have been necessary throughout the smelting agenda. New equipment has been necessary for transportation, unloading, sampling, bedding and moisturing in all smelting plants, especially the custom smelter. During the early days of "flotation," little was known about filtering or the use of an alkaline circuit; often the concentrate going to the smelter contained 20 to 25 per cent moisture. It is easy to imagine the difficulty arising with a product of this nature when it had to be shoveled by hand labor. To meet these conditions, mechanical unloading and sampling devices were soon developed. In many instances such good progress was made that actual costs for handling this unfavorable product were lower than those formerly incurred on the old product. Today most sampling of copper ores and concentrates is being done by mechanical sampling, pipe or augur sampling, or shovel sampling. Where concentrates are uniform in metal content, a great many of the plants now use pipe or augur sampling. For spotty ores, the old shovel sample with cone and quartering during the final stages is still in use. Where big tonnages are handled, mechanical sampling of concentrates is being done, with satisfactory results. To curtail slow and tedious cutting and mixing procedure, mechanical mixing boxes, splitters and cutters are used to cut down labor costs. MILLING As crude ores become scarcer, the use of milling operations increases. The few crude ores that are still smelted are used as fluxing types. To use these ores finer grinding has been found advantageous. This has made for better bedding and fluxing conditions, which in turn makes for faster smelting, lower fuel consumption and better metal recovery. The degree of fineness is more or less determined by the nature of the product. Most plants have set a standard of through ¾ -in. mesh screen for roaster- reverberatory smelting and through ¾ in. mesh screen for converter fluxes. For some refractory ores; even finer grinding has been found to be advantageous for good reverberatory smelting.

Jan 1, 1944

By Henry E. Wood

In my opinion, the concentration of minerals by flotation is the most interesting problem in ore-dressing, and will command eventually far more consideration than it has at present. For many ores it furnishes a complete method of concentration absolutely independent of specific gravity, and thus simplifies the milling of many difficult combinations. Not having to recognize the influence of specific gravity, we are also able to dispense with some of the complications resulting from classifying-conditions. Where flotation cannot be used for a complete separation of the minerals from the gangue, it will be found, in nearly all cases, to save those portions which are generally lost by reason of their fine state of division. For this reason, it should be looked upon mainly as an aid to general concentration, although there are many ores so well adapted to flotation that more than 90 per cent. of the valuable metals can be recovered from them in one operation by this process. In presenting the results of my investigations in flotation, I have endeavored to theorize as little as possible. That side of the subject has been extensively discussed by others. My earliest work with flotation was done in 1895, when I used various oils, grease, soap, etc., with results that were remarkable. I did not realize then that with water alone equally good separations could be made. Up to 1906, my endeavors were confined to attempts to keep the concentrates on the tables well wetted and away from exposure to the air. In common with others, I observed that when there mas any obstruction in the wash-water on the table of sufficient size to divert the water to either side, the concentrates collected, and, on exposure to the air, would promptly float away. This convinced me that the sulphides were all good "swimmers," and that if,

Jan 1, 1913

Jan 1, 1953

By E. S. Machlin, Morris Cohen

GRENINGER and Troiano' were the first to establish the fact that the habit planes of mar-tensitic products are usually planes of high indices. In steels containing 0.55 to 1.4 pct C, the habit plane indices are {225}A.* In steels with more than 1.5 pct C and in Fe-Ni alloys, the indices are {259In. The presence of both habits in certain alloy steels has been reported recently." Several investigators"-" have subsequently attempted to provide an understanding of these complex habit relations. Bowles'6 work is the most recent and the most successful. Like Greninger and Troiano, Bowles concluded that the transformation occurs in two steps, the first, a strain (or displacement) that is homogeneous throughout the volume of the martensitic plate, while the second is a strain that is homogeneous only within relatively small portions of the martensitic plate. The first strain yields the measured tilt of the specimen surface, but does not produce the final martensitic structure. This and the correct lattice orientations are achieved by the second strain. Bowles also reasoned that each strain could be described by the motion of a plane of no rotation and no distortion (hereinafter called the invariant plane) in a direction not necessarily contained in the plane.** In applying these considerations to steels with {225}a habits, Bowles found that the habit plane coincided with the invariant plane of the first strain, a result which signified that the atoms move along certain paths during the transformation. Whether this correlation results from the existence of some sort of a plate nucleus6 lying along the invariant plane of the first strain, or whether the invariant plane primarily defines the preferred directions of propagation of the first strain, will be discussed in a later section. There are two obstacles to the general acceptance of Bowles' treatment: 1—it has not been shown that elements of his double-strain analysis are unique, and 2—it is not known whether his treatment applies to transformations yielding the {2591A habit. Unless these two questions are resolved, the correlation between the habit and invariant planes in the {225}A systems might be regarded as coincidental. Experimental Procedure Using a 70 pct Fe-30 pct Ni alloy as an example of a {2591A habit system, preliminary attempts were made to obtain a double-strain solution based on a Nishiyamax** set of orientation relations and on a Greninger-Troianot set, adopting the stereographic technique described by Bowles" who used the Kurd-jumow-Sachstt set in connection with the {225}A habit. These attempts were unsuccessful because the method is essentially one of trial and error and requires either exceedingly good luck or a prior knowledge of the results being sought. Consequently it was decided to measure independently the strain associated with the formation of a martensitic plate as well as the habit-plane indices of the particular plate. By means of matrix algebra, the measured strain was applied to the austenite lattice, whose orientation with respect to the strain was determined, in order to ascertain whether the resultant structure would have the lattice of martensite. This was not found to be the case, and hence it was assumed that the measured strain was the first of two Bowles-type strains, characterized by the motion of an invariant plane. A solution of this displacement was obtained in terms of the invariant-plane indices and the direction of motion of the atoms. Then the second strain

Jan 1, 1952

By Frederick Apgar

(Butte Meeting, August, 1913.) THE valuable results that have followed the application in recent years of microscopic methods of research to problems of ore genesis have been significant, but possibly the recognition of their practical importance is not as general as might be, and while, as a scientific method of investigating ores and rocks, the advantage derived through the use of the microscope is unquestioned, its utility as an aid in solving shining problems arising during actual every-day mine examination and operation may not be fully appreciated. Perhaps the roost logical method of showing some of these practical applications of the microscope will be to consider first the prospect stage of a mining venture, then the uses to which the instrument may be put during the operation of a working and developed mine, and, finally, to discuss some of the problems of a metallurgical nature that ii-my arise during milling and smelting the ore. The valuation of mining property as a preliminary to acquiring ownership or determining the advisability of investing time and money in an enterprise is one of the most important and delicate problems that come before the mining engineer. The many and variable factors that have to be taken into account, as, for example, the geology of the district, availability of supplies, probable mining costs, transportation facilities, and the quality of ore, require a careful balancing of costs against recoverable values.

Jan 6, 1913

By A. G. Worthing

Black: Bodies.-In the ordinary conception, a black object is an opaque object that reflects but little of the light that is incident on it. This means naturally that such an object is a good absorber of luminous radiation. The black body; which is so closely connected with high-temperature measurements, represents the limit in blackness of all black objects. It is a body that not only absorbs all visible radiations but also all other radiations in the infra-red and the ultra-violet regions of the spectrum which are incident on it. No substance is known that is completely black; platinum black, one of the nearest if not the nearest representative of the ideal, reflects 1 per cent. or so of ordinary visible radiation. The closest approach to the ideal is a small opening in the wall of a relatively large opaque cavity. Any radiation incident on this black body will be almost completely absorbed if the relative dimensions are properly chosen no matter what the material may be. The great difference between the blackness of such a cavity and of lampblack, for instance, will be apparent to one who makes the simple test. Non-black Bodies.-The field of non-black bodies covers all real bodies. Their characteristics are extremely varied. So far as absorption of radiation-is concerned, these bodies range practically from the almost completely black, platinum-black, and lampblack, which absorb all but a fractional part of 1 per cent. or so of the incident radiation, by an infinite variety of steps to freshly polished silver, which ordinarily absorbs only a few per cent. The exact percentage absorbed depends not only on the nature of the incident radiation, but also on the temperature of the body, the condition of its surface, the angle of incidence, the nature of the surrounding medium, and on certain other less important conditions. As consequences of these varied characteristics, we have not only the differences of color of ordinary objects, but also the changes of color that any one object undergoes on heating or when lighted front various directions. This complexity of the phenomena, in a way, is responsible for the meagerness of knowledge, regarding materials at elevated temperatures. Measurement of High Temperatures.-Excepting in cases where the thermocouple or the gas thermometer are applicable, in which case the temperatures obtained are true temperatures regardless of-the material" studied, high, temperatures are almost always, if not always, determined from measurements of radiation. In fact, determinations of temperature from this latter point of view are often so much more convenient than the thermocouple and especially the gas-thermometer determinations that, in the region where all of these types of measurements may be made, the radiation measurements are often preferred. This is true even though the temperatures usually thus directly determined are not the actual temperatures, a consequence of the sources of the radiation being non-black bodies; in other words, a consequence of being concerned with iron, or glass, or tungsten instead of small openings leading to relatively large-cavities uniformly heated. Coordination of Experimental Results.-In order that data on iron, glass, tungsten, or other non-black bodies obtained in one laboratory, may be, correlated with similar data obtained elsewhere, temperatures must be expressed on a common scale. The true temperature scale is the natural scale for this purpose it is ordinarily the scale to which all other temperatures can be most directly reduced. When the measurements depend on the radiation, a knowledge of emissive powers repre-

Jan 9, 1919

By Robert L. Greyer, John I. Myung

The Birdwell 3-D Velocity Log displays photographically the amplitude of elastic waves as a function of time and of the depth of the logging tool in a borehole. The elastic waves are generated by a magneto-strictive source transducer and detected by a receiving transducer, which is at a fixed distance from the source. The output of the receiver, which is proportional to the amplitude of the received elastic waves, modulates the light that exposes the film record. The duration of the receiving time can be selected to record the entire wavetrain of late events or to record only early events at a finer time scale. When a full complement of elastic waves (i.e., the refracted compressional wave, composite shear wave, direct fluid wave, and boundary wave) is recorded, their velocities and the density of the borehole fluid provide the information necessary to compute the elastic moduli and density of the rock surrounding the bore-hole. The differences between the values of the moduli determined from measurements of 3-D Velocity Logs and by other better known techniques are small, well within the limits of experimental error, when the velocity log is interpreted by an experienced seismic analyst. INTRODUCTION Quantitative descriptions of the mechanical properties of the rock environment have long been basic requirements of planning, design, and quality control of engineering projects. Because of this need, many techniques for determining the elastic moduli from static and

Jan 1, 1971

By P. L. Hendricks, J. W. Spretnak

The interstitial atom principally responsible for the yield point and strain aging in electron-beam-melted tantalum is identified by analysis of the kinetics of the return of the yield point after an increment of plastic deformation. Two sets of specimens contained two levels of oxygen with very low hydrogen contents and the third set had comparable oxygen and hydrogen contents. The activation energy for the return of the yield point agrees well with that for diffusion of oxygen for the first two sets of specimens. For the third set of specimens, the activation-energy value lies between those for diffusion of hydrogen and for diffusion of oxygen. The advent of the dislocation model of plastic deformation in metals has revitalized interest in the yield point and strain aging in bcc metals containing a certain minimum content of interstitial solute elements. Much theoretical and experimental work has been performed in recent years to elucidate the detailed mechanism of these phenomena. The purpose of this investigation is to attempt to identify the principal interstitial element responsible for the yield-point phenomenon in electron-beam-melted tantalum by analysis of the kinetics of the return of the yield point after an increment of plastic deformation. Some of the earlier theories of the yield-point phenomenon proposed a grain boundary film of iron carbide. Such models could not satisfactorily explain all features of strain aging and the yield-point phenomena. The most widely accepted explanation is that of Cottrell,1 later extended by Cottrell and Bilby.2 Strain aging is ascribed to "locking" of dislocations by interstitial solute "atmospheres". The yield-point phenomenon results when the dislocations are torn away from their atmospheres. The strain-aged condition is re-established after sufficient time to allow the interstitial atoms to diffuse to the dislocation lines and re-establish the locking atmospheres. Clearly, the Cottrell-Bilby model is concerned with the bulk of the grain and does not specifically involve the grain boundary. The recent modification of the Cottrell-Bilby model is a redirection of attention to the role of the grain boundary and the possibility of multiplication of a limited number of free dislocations rather than unlocking all of the dislocations. Theories have been advanced by Hahn3 and conrad4 which are modifications of the Cottrell-Bilby theory. The model proposed by Hahn indicates that, although the possibility of un- locking anchored dislocations is not excluded, it implies that unlocking is not necessarily required to explain yield drop. Locking of dislocations during the aging treatment is a necessary part of the theory; however, it assumes that dislocations once locked remain locked. It is suggested that the yield drop observed is a result of the following factors: 1) the presence of a small number of mobile dislocations initially, 2) rapid dislocation multiplication, 3) the stress dependence of dislocation velocity. In the case of bcc metals, locking is considered to be the means by which dislocations are immobilized. Cold working of the metal results in the generation of larger numbers of new dislocations and the stress dependence of the dislocation velocity accounts for yield drop observed. Conrad' has proposed a model similar to the one just described which applies to strain aging of iron and steel and which logically could be extended to other bcc metals. This model also does not require large-scale unlocking of dislocations. It is proposed that, during initial loading of a specimen below the upper yield stress, a few dislocations are torn free of their Cottrell atmospheres at regions of stress concentrations. With an increasing stress, some multiplication of dislocations occurs by a double cross slip mechanism, thus giving a preyield microstrain. At some critical stress represented by the upper yield stress, sudden profuse multiplication of dislocations occurs, enabling plastic flow to proceed at a lower stress. In this model, microstrain, preyielding, and flow represent the movement of free dislocations. It should be noted that this model also requires the locking of dislocations by interstitial solute atoms for the occurrence of a yield point; however, unlocking of large numbers of dislocations is not required. If it is assumed that the yield point will return when some fraction of free dislocations produced during pre-straining are pinned, the number of solute atoms required to pin unit length of a dislocation line can be calculated when prestrain and reloading are done at the same temperature and strain rate. Since the migration of solute atoms back to the stress fields of dislocation lines is controlled by the diffusion rate of interstitial solute atoms, it is to be expected that the activation energy for strain aging would be identical to the activation energy for diffusion. It would also be expected that the strain aging observed will be controlled by the fastest diffusing species capable of producing locking over the temperature range investigated. The rate of yield-point return has been found to be adequately expressed by an empirical rate equation of the form: rate=Ae-Q/RT [1] where A = constant, Q = activation energy, R = gas constant, and T = absolute temperature. Cottrell and Bilby2 have expressed the number of atoms per unit length of dislocation line which arrive

Jan 1, 1967

The Hurghada field is still the major producing field in Egypt. There was almost no activity in the Abu Durba field during 1936 and no new evidence is available. The following table summarizes the information on the Hurghada field for the year 1936. Hurghada Field Age of field to end of 1936, years.................... 23 Producing area for gas and oil, acres................. 1,050 Barbels Total oil production to end of 1936.................. 29,046,572 Total oil production during 1935.................... 1,212,182 Total oil production during 1936.................... 1,218,708 Daily average during November, 1936............... 3,249 MillionB CU. Ft. Total gas production (Aug. 1925 to end of 1936)...... 3,966 Total gas production during 1935................... 278 Total gas production during 1936................... 280 Maximum daily in 1936............................ 0.9 Number of producing wells completed to end of 1936... 94 Number of producing wells completed during 1936. ... 3 Number of wells abandoned during 1936............. 3 Producing wells at end of 1936...................... 768 Average depth of bottom of producing wells, ft....... 1,720 Average depth of top of producing horizon, ft......... 1,598 Character of oil, approx. average during 1936: Gravity at 60' F., 0.900; base mixed. Character of gas, approx. average during 1936: gallons gasoline per 1,000 CU. ft., 6.2. Producing rock (main): Nubian sands, Cretaceous; character, sand rock and sandy shales. 1 The figures given by the author were in tons. A conversion factor of 6.98. based on 0.900 sp. gr., was used to obtain the number of barrels.—Ed. 2 All pumping.

Jan 1, 1937

[NOTE.-The following discussions of papers contained in this volume are printed without regard to order of succession. It has been impracticable to secure from the various parties, corrected reports of their contributions in time to effect any particular desired arrangement in this respect. The papers of Messrs. Pourcel, Osmond and Sauveur, were considered at Chicago together with others of cognate character ; and the whole discussion will be found in vol. xxiii., under the head, " Physics of Steel."]

Jan 1, 1894

By H. H. Hausner, H. S. Kalish

IN recent years zirconium and beryllium have become of great interest because of their special properties. Zirconium is known for its remarkable ability to absorb the gases oxygen, nitrogen and hydrogen, has extensive use as a getter in electron tubes and has indeed become the primary metal in the manufacture of photoflash bulbs. Beryllium is of interest because it is light metal and as such could supplement aluminum and magnesium in light metal applications. The late development of zirconium ductile at room temperature produced by both the iodide and calcium reduction methods has stimulated frequent articles on this metal in the recent literature. Beryllium is so closely akin to zirconium crystall-ographically that some investigators are of the opinion that beryllium should be ductile at room temperature if it were pure enough. The crystallographic relationship of beryllium and zirconium, the interest created in Be-Zr alloys where the zirconium is believed to function as a remover of solid solution gas in beryllium and thus increase the ductility of the beryllium rich alloy, and the amenability of these metals to powder metallurgy methods stimulated this approach to an investigation of the system Be-Zr. Preliminary work showed that a zirconium compact melted when pressed in contact with a beryllium compact and sintered at 1250°C, without any apparent final bond between the two. A search of the literature revealed nothing pertinent about the Zr-Be system or about any zirconium - beryllium alloys. In 1936 Misch³ vaguely identified the compound ZrBe2 and reported that it has a deformed cubic structure. Two patents," , were issued to Mach-lett Laboratories in 1943 and in 1946 regarding the addition of small amounts of zirconium to beryllium in order to improve the ductility of beryllium so that it may better be used for X ray windows. In considering the alloy formation of beryllium with other metals Raynor thought it unlikely that zirconium would have any solid solubility in beryllium. From this indefinite information nothing could be ascertained about the possible use of Zr-Be alloys or the use of these metals intimately. A brief preliminary study of the system Zr-Be by powder metallurgy methods was undertaken to provide regions for more intense studies of Zr-Be alloys and as a guide to a formal phase diagram determination. The investigation described in the following pages was completed in less than three weeks. The usefulness of this rapid method to facilitate phase diagram studies and new alloy investigations will be shown. Materials and Procedure Zirconium powder was produced from crystal bar stock of high purity supplied by Foote Mineral Co. The crystal bar was converted to hydride at 730°C, crushed, and the hydride decomposed in purified argon at 850°C. 60 pct of the powder passed through a 325 mesh screen, 40 pct of the powder was —140 mesh, +325 mesh and the average particle size of the total was 8 to 12 microns. The beryllium powder was used as re-

Jan 1, 1951

By E. S. Machlin

RECENTLY, there has been much activity in the field of nucleation of martensitic transformations.'- One of the problems in this field is the calculation of the rate of nucleation (number of plates nucleated per unit untransformed volume per unit time) in terms of observable parameters. Two such observable parameters are the fraction of the length of a straight line which corresponds to the portion of the total length of the line that lies in the martensitic phase and the number of plates intersected by this straight line per unit length of line. Because of the necessity of a valid answer to this problem, the following investigation was undertaken. Although this problem has been treated in the past, a derivation of the relation between the volume and linear fractions of martensite will be described to illustrate the method used in the succeeding analyses. It is assumed that the martensitic plates are in the form of a right circular cylinder having a small height relative to the radius of the base. The volume fraction of martensite is then: fr = lXNl,hjAl [1] where f, is the volume fraction of martensite, and Nij is the number of plates per unit total volume having the area Ai and the height hi. The linear fraction of martensite is obtained as follows. For the plates having the particular area A, and height h,, the fraction sin 0 dB* will have their cylinder axes between the angles 0 and 0 + d0 to the straight line along which the linear fraction of mar-

Jan 1, 1953

By R. Hogg

INTRODUCTION As mineral particles are made smaller and smaller, it follows that their surfaces assume a greater and greater importance. In the extreme, the colloidal systems are characterized by the complete dominance of surface over bulk properties. Surface characteristics and properties will clearly influence any fine-particle processing operation. Comminution, for example, is a process of creating new surface. Agglomeration, on the other hand, may involve the reduction of surface area and the forces involved are generally surface forces. All mineral separations, solid-solid as well as solid-fluid, involve the treatment of two or more phases (solid plus liquid and/or gas). As the interfacial area increases, so will its effects on processing. Both physical and chemical separations are influenced by interfacial phenomena. Gravity separations are usually performed in a liquid phase and may be affected, for example, by the wetting characteristics of the solids. Flotation processes, of course, are based on the exploitation of differences in surface properties. Hydrometallurgical processing usually involves interfacial chemical reactions, e.g. leaching. The rates of such reactions depend on surface area and may be influenced by electrochemical effects in the electrical double layer at the solid-liquid interface, or by adsorption of reactant and/or product species from solution. In characterizing a mineral surface, it is important to consider first the surface area, since this determines the relative importance of the interfacial effects. The structure and chemical composition of the surface, which may depend on segregation of impurities within the solid and on adsorption from the external environment as well as on the bulk composition of the solid, will generally determine such

Jan 1, 1980

By Arthur West

It is the purpose of this paper to describe briefly some recent large power stations for blast furnaces, where the blast is exclusively supplied by gas engines using furnace gas. The stations are given in the chronological order in which they were designed, in order to indicate the various improvements suggested by experience. Fig. 1 shows the blowing-engine station of the Bethlehem Steel Co. at Bethlehem. Although the picture shows only five blowing engines, the house now contains 11 engines. In the diagrammatic plan the arrow shows the position and direction of camera. This station handles five modern blast furnaces of 450 to 500 ions capacity each. In this, as in all the other stations described in this paper, each furnace is blown by two single tandem gas engines. Ten engines are thus required for five furnaces, leaving one single tandem spare engine. This spare capacity has been shown by several years' experience at Bethlehem to be adequate to insure continuous operation. The engines in the Bethlehem station are right hand and left hand, arranged in pairs. The outboard bearings of each pair are close together so that there is not room for passageway between them. On the right of the picture are shown the inclined drums communicating with the cold-blast lines outside of building, so that any engine may be operated on any furnace. The illustration shows four cold-blast gate valves with pipes passing through wall, but since the photograph was taken the drums have been extended to take care of a fifth valve for a fifth furnace. At the extreme back of the picture can be seen the tubs of three twin vertical-horizontal Southwark steam blowing engines, which, although of modern design and as good as new, are not operated because of the greatly reduced blowing cost shown by the gas blowing engines. The next station built is shown in Fig. 2. This is the plant of the Minnesota Steel Co. at Duluth, Minn., and is at present constructed for five engines, to handle two furnaces, with one spare engine. The engines are of practically the same size as those at Bethlehem. Instead of being arranged in right-hand and left-hand pairs, as at Bethlehem, all the engines are of the same hand; this arrangement has some ad-

Jan 1, 1915

By R. S. Dean

MANY studies have been made of the properties of steel produced by adding varying amounts of sponge iron to the charges used in steel-making furnaces.1-3 The results of these previous studies, however, have failed to disclose a reason for the belief of steelmakers that steel made in this way is definitely different from steel made entirely from scrap or iron melting stock. This paper deals chiefly with the structure of the sponge iron, of the wrought iron made by welding the sponge iron into blooms, and of the steel made by melting the forged and rolled blooms. It is believed that the structure of the final steel is inherited from the ore and that this inherited structure produces marked differences in the properties of the steel and explains the feeling of steelmakers which is based on their experience. Three kinds of sponge iron were used in this investigation: One made from a limonite ore reduced with natural gas, one made from a hematite ore reduced with natural gas, and one made from a magnetite ore reduced with charcoal. The sponge iron made by reduction with natural gas

Jan 1, 1935

By Paul T. Allsman, E. W. Newman

TRENCHING, sampling, and core drilling in Stillwater and Sweetgrass Counties, Mont., by the Bureau of Mines have delimited over 5,000,000 tons of chromite ore containing more than 20 per cent chromic oxide. The Benbow and Mouat-Sampson mines have been developed and are fully equipped for mining and milling 500 tons and 2000 tons a day, respectively.

Jan 1, 1944

By David W. Brunton

Mine-drainage and the ever-increasing demand for water on the plains have within the past few years necessitated the driving of a great number of adits and tunnels, including many of considerable size and great length. In most instances, existing conditions have called for extreme rapidity of execution; and this necessity, coupled with the high altitudes at which most of the work has been carried on, excessive freight-rates, and difficulty of access, has involved many complex and interesting problems. One of the most rapidly executed undertakings of this class is the Laramie tunnel, recently completed for the Laramie-Poudre Reservoirs & Irrigation Co. This tunnel is driven through Green ridge, a spur of the Continental Divide, which separates the Laramie river from the Cache-la-Poudre in Laramie county, Colo. Green ridge is extremely persistent, and further northward in Wyoming is known as Sherman hill, the highest point on the Union Pacific railway. At the point where the tunnel is driven, two opposing bends bring these streams within 2.5 miles of each other, with a difference in elevation of 500 ft. The rock exposed on the banks of the two rivers does not differ materially in hardness; and, without a geological study of the conditions involved, it would appear that the difference in the depth of erosion of the two streams is due principally to the greater volume of water at this point in the Cache-la-Poudre, which has a drainage-area above the tunnel-portal of 110 sq. miles, as against 30 sq. miles of natural drainage for the Laramie. To increase the water-supply at the tunnel, however, this latter amount has been augmented by two side collection-canals, which bring the available drainage-area up to 84 square miles. The nearest railroad shipping-point to the eastern portal is

Jan 1, 1913

By James K. Stanley

Preferred orientation, particularly in irons and low-carbon steel, is a phenomenon that is both of considerable importance and theoretical interest. At times it is a liability and at other times an asset. In deep-drawing operations, preferred orientation is extremely undesirable because it necessitates trimming operations and increases scrap loss. Furthermore, oriented metals are likely to crack more easily than randomly oriented material because the forming of symmetrical and unsymmetrical shapes out of preferentially oriented metals and alloys increases the probability of rupture in regions of high stress, owing to differential ductility.' In the electrical industry, on the other hand, preferentially oriented silicon irons are in demand for transformer application because of the improved magnetic permeabilities in the rolling direction.2 This phenomenon of preferred orientation in soft magnetic materials has been responsible for the tremendous improvement in transformer design and construction in recent years. Directional properties in metals have received a great deal of attention in the metallurnical -literature,3-9 in which much of the information reported about orientation has been obtained by conventional methods, mechanicai properties and X-rays. A wealth of data has been obtained and often at a great expenditure of time. The recent introduction of the magnetic torque measurements on ferromagnetic materials provides a very simple and rapid method of evaluating orientation. The judicious use of the method can supply important information, but it should be borne in mind that such studies must be supplemented by X-rays, optical methods,10 and etch and pressure figures" to get a rational understanding of the orientation phenomena. No claims are made that the magnetic torque of evaluating orientation will reveal the behavior of the metal in deep drawing. For this purpose the accepted tests for deep-drawing quality must be used. For a good drawing stock, which must have low impurities, desirable grain size, ductility, strength, hardness, good surface, random orientation, and good recrystallization behavior, it cannot be expected that any simple test will be satisfactory for appraising all the factors. The only factor on which the magnetic method can be used is orientation, which is, of course, of considerable importance. When directionality can cause a 10 to 15 per cent change in tensile strength and a IOO to 300 per cent change in tear length,12 it goes without saying that a reliable as well as rapid method for detecting these changes would be desirable. There are certain inherent advantages in testing orientation by the torque method: The method is rapid with the proper type of equipment; no elaborate preparation of specimens is required—it is only necessary to punch or machine a I-in. disk of the sheet material and insert it into the testing device.

Jan 1, 1944

By James K. Stanley

Preferred orientation, particularly in irons and low-carbon steel, is a phenomenon that is both of considerable importance and theoretical interest. At times it is a liability and at other times an asset. In deep-drawing operations, preferred orientation is extremely undesirable because it necessitates trimming operations and increases scrap loss. Furthermore, oriented metals are likely to crack more easily than randomly oriented material because the forming of symmetrical and unsymmetrical shapes out of preferentially oriented metals and alloys increases the probability of rupture in regions of high stress, owing to differential ductility.' In the electrical industry, on the other hand, preferentially oriented silicon irons are in demand for transformer application because of the improved magnetic permeabilities in the rolling direction.2 This phenomenon of preferred orientation in soft magnetic materials has been responsible for the tremendous improvement in transformer design and construction in recent years. Directional properties in metals have received a great deal of attention in the metallurnical -literature,3-9 in which much of the information reported about orientation has been obtained by conventional methods, mechanicai properties and X-rays. A wealth of data has been obtained and often at a great expenditure of time. The recent introduction of the magnetic torque measurements on ferromagnetic materials provides a very simple and rapid method of evaluating orientation. The judicious use of the method can supply important information, but it should be borne in mind that such studies must be supplemented by X-rays, optical methods,10 and etch and pressure figures" to get a rational understanding of the orientation phenomena. No claims are made that the magnetic torque of evaluating orientation will reveal the behavior of the metal in deep drawing. For this purpose the accepted tests for deep-drawing quality must be used. For a good drawing stock, which must have low impurities, desirable grain size, ductility, strength, hardness, good surface, random orientation, and good recrystallization behavior, it cannot be expected that any simple test will be satisfactory for appraising all the factors. The only factor on which the magnetic method can be used is orientation, which is, of course, of considerable importance. When directionality can cause a 10 to 15 per cent change in tensile strength and a IOO to 300 per cent change in tear length,12 it goes without saying that a reliable as well as rapid method for detecting these changes would be desirable. There are certain inherent advantages in testing orientation by the torque method: The method is rapid with the proper type of equipment; no elaborate preparation of specimens is required—it is only necessary to punch or machine a I-in. disk of the sheet material and insert it into the testing device.

Jan 1, 1944

By Anthony Folger, Charles E. Straub

Kansas produced 38,150,878 bbl. of oil in 1928 and 40,658,170 bbl. in 1929, thereby retaining its rank as fourth among the oil-producing states of this country. Production for 1928 was less than that for 1927 (Fig. 1) because of a decrease in the number of completions, but the average initial production per well (Table 1) shows an increase due to the completion of wells of comparatively large capacity in the new Valley Center pool of Sedgwick County. This increase in average initial production per well was further augmented during 1929 by completion of additional wells of comparatively large capacity in the Valley Center pool and the new Greenwich pool of Sedgwick County. Production for 1929 exceeded that for 1928 and threatened to exceed all records except that of 1918, however, production was prorated in

Jan 1, 1930