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By C. R. Dale

The need for instruments to measure the movement of fluids and gas in wells has been recognized by engineers for many years. Information regarding flow in the producing interval has a direct bearing on completion practices in new wells and also provides information on the production characteristics of the well. Many hours of engineering time are spent in planning and completing wells but knowledge as to whether or not the original planning has produced the desired results has not always been complete. Many questions such as the following often arise: Why is it that two wells are completed under supposedly identical conditions, yet one well is a good one and the other is a poor one? Are the sands that look the best on the electric log contributing to the production? These and many other conditions in the producing well need to be under- stood in order to develop more efficient production practices and to improve on methods of completing new wells. It is the purpose of this paper to briefly describe one type of instrument, outline the methods of running the equipment and show the results of surveys made under various conditions. With an understanding of the use of this type of survey its importance can be evaluated in relation to the problems encountered by the operator. DESCRIPTION OF INSTRUMENT The instrument is a velocity recorder employing a clock-controlled 16mm film for recording the rpm of an extremely sensitive rotor which is rotated by the flow of fluids or gas in a well. The helical-vaned rotor and shaft, weighing one-half of one ounce are an integral unit exposed to the well fluids and are the only moving parts not enclosed in the fluid-tight housing. No packing or fluid seal of these parts is necessary and the shaft is mounted top and bottom on special jeweled bearings. Fig. A is the lower part of the instrument showing rotor and shaft with the protecting housing sleeve removed. The rpm of the rotor is recorded on the moving film by a combination electrical and optical system. The record is a series of dashes on the film, each dash and space representing twenty (20) revolutions of the rotor. (Film record of survey made in California well showing station recordings at various depths.) As the movement of the film is controlled by the clock the number of dashes and spaces in one minute of film travel represents the rpm of the rotor. The range of the instrument is from 0 to 2,500 rprn. The barrel or housing is 1-11/16 in. OD and seven feet long. Various types of expanding fluid traps are attached to the lower end of the instrument to direct the flow through the 1 in. orifice containing the rotor. The fluid trap for upward flow is shown in Figs. B and C. This assembly consists of eight arms with light spring

Jan 1, 1949

By J. S. Billheimer, B. H. Sage, W. N. Lacey, C. G. Yundt

As a part of a general investigation of the separation of bitumen from hydrocarbon mixtures a study was made of a restricted quaternary system composed of methane, decane, tetralin, and bitumen. The work was limited to a pressure of 8000 psi, a temperature of 220 °F, and to a fixed relative proportion of decane, tetralin, and bitumen. The measurements permitted the determination of the distribution of these components in each of the fluid phases. It was not possible to distinguish a second liquid phase in the course of these measurements. Gas-liquid equilibrium "constants" of each of the components were found to vary markedly with the composition of the system while temperature and pressure remained fixed. INTRODUCTION The separation of bitumen frorn naturally occurring hydrocarbon mixtures has been of importance for a number of years in the production of petroleum, especially in the California area. The deposition of this material from crude oils was noted in earlier studies of the solubility of natural gas in crude oil.¹,²,3 Studies of the separation of bitumen from crude oils from the Greeley and Santa Fe Springs fields were carried out."." The behavior of these systems appeared complex and studies of two restricted ternary systems involving mixtures of n-pentane, tetralin, and bitumen,' and of decane, tetralin; and hitumen, confirmed this belief. Reviews of the literature pertaining to the separation of bitumen from naturally occuring and refined hydrocarbons are available." The important effect of methane in the separation of bitu- men from naturally occurring hydrocarbon mixtures was apparent from the earlier studies and for that reason it appeared desirable to investigate a restricted quarternary system involving mixtures of methane. decane, tetralin, and bitumen; data concerning the behavior of mixtures of decane. tetralin. and bitumen having already been obtained.V his study was restricted to a pressure of 8000 psi," a temperatue of 220° F, and fixed relative proportions of bitumen, decane. and tetralin. This composite constituent, hereinafter designated as the less volatile constituent, was made up of 0.0455 weight fraction bitumen. 0.0909 weight fraction decane, and 0.8636 weight fraction tetralin. The experimental method involved bringing together mixtures of methane and the less volatile constituent in varying proportions in a constant volume container at the pressure and temperature indicated above. The composition of each of the phases was determined and from this the extent of the separation of bitumen was established. MATERIALS The bitumen used in this investigation was obtained from the same stocks employed in earlier studies. The crude material from the North Coles Levee field was stored in the laboratory] in a closed drum for a period of five years. Several samples from this stock were subjected to refining operations which were described earlier,' and every effort was made to follow the same procedure in all cases. It was necessary to prepare supplies of bitumen for this investigation at two rather widely different times. These materials have been identified as samples 1 and 2. The composition of the crude bitumen after it was washed with n-pentane at room temperature

Jan 1, 1949

By R. G. Patterson

The usual procedure in determining the magnetic susceptibilities of rocks and formations has been to take samples in the field and measure their volume susceptibilities in the laboratory, using one of numerous methods available. In none of these methods is the measuring instrument suited for field use. Usually the sample is pulverized; sometimes it is machined to a desired sue and shape, and in one method1 a cast of the sample is made and the susceptibility of the rock compared with that of a material of known susceptibility of the same size and shape, made from the cast of the original sample. Some writers assert that the difference in susceptibility of a rock sample in powdered and solid forms is negligible, and while doubtless this is true in many cases there are others in which the difference becomes appreciable. Further, the susceptibility of a small specimen may differ from that of the rock from which it is taken, owing to the stresses produced by the hammering or other forces used to obtain the sample and shape it for testing. Wilson2 found that an individual specimen of granite had about the same susceptibility in the solid as in the powdered form, but that pieces from different parts of the rock varied as much as 750 per cent because of unequal distribution of magnetite. The most accurate value of susceptibility would, obviously, be obtained from averag- ing a number of tests on the undisturbed rock instead of from one or two samples. No such procedures have been published, to the writer's knowledge. It is the purpose of this paper to describe a method by which susceptibilities of rocks may be determined in place by means of a portable instrument. Method The principle involved in this new method is that there is a change in inductance of a coil due to the presence in its magnetic field of a paramagnetic or dia-magnetic medium. In this case, however, the windings of the coil do not enclose any part of the rock under test. Instead, the coil is circular, being small in cross section as compared to its radius, and consists of several hundred turns of fine wire. It is placed flat on the rock of which the susceptibility is to be measured. Thus only part of the magnetic field from the coil penetrates the rock under test. The relation between the change in field strength or inductance of the coil and the susceptibility of the medium will be developed later. To measure the change in the inductance of the coil due to the presence of a magnetic material an alternating-current inductance bridge was chosen. Description of Apparatus Of many alternating-current bridge methods applicable,3 the one shown in Fig. 1 (Owen's bridge') was adopted for its simplicity and sensitivity. In Fig. I, the test coil is indicated by PlL1. It is connected to the bridge by about

Jan 1, 1946

By A. A. Jr. Smith, J. S. Smart

The controlled amounts of phosphorus, arsenic, sulphur or selenium found in commercial coppers perform a variety of highly useful functions. Indeed, a large segment of modern copper technology is essentially dependent upon the presence of one or more of these elements. Consequently, the literature contains many references to their effects but the scope is broad and has been only partly covered. New data are presented herewith directed toward a better understanding of the basic behavior of these elements in copper, with particular emphasis on the composition range o to 0.05 per cent. These data are a part of a general program of research on the effects of impurities on the properties of oxygen-bearing and oxygen-free copper, other portions of which have been reported previously. Schematically, the behavior of individual elements is determined from measurements of conductivity and softening temperature,'v2 and the binary alloys employed are synthesized from high-purity copper in order to eliminate interference from the effects of extraneous impurities. Alloys of selected composition were first prepared in the oxygen-free form by continuously casting the melts in the form of %-in. diameter rod. Oxygen was added subsequently to portions of the alloys, either by remelting or by diffusion at 8jo°C. from a surface scale. Test wires wcre drawn one B. and S. number per pass, using four 30-min. 600°C. anneals at 0.3125, 0.257, 0.204 and 0.162 in., and a final cold reduction of 75 per cent to 0.081 in. Oxygen-bearing slugs made by remelting nere hot-rolled to 4ia in.. drawn to 0.162 in., annealed for 30 min. at 6o0°C. and cold-drawn 75 per cent to 0.081 inch. The alloys containing phosphorus, having been compounded very early in the program, were prepared in the form of 3i6-in. rod, and processed to wire with only the last three intermediate anneals listed above, all of these having been conducted in commercial nitrogen. In addition, the conductivity anneals on these alloys were also performed in the same atmosphere, and the small amount of oxygen present as an impurity in the gas resulted in some loss of accuracy at temperatures of 700' to 8o0°C., as will be shown later. Subsequently, the anneals for all oxygen-free alloys were conducted in hydrogen to prevent oxidation, and purified nitrogen was employed only for oxygen-bearing samples. All conductivity anneals wcre of one hour duration followed by a rapid quench in 10 per cent HZSO*. Effect of Phosphorus The widespread use of phosphorus as a deoxidant has resulted in universal appreci-

Jan 1, 1946

By E. A. Nesbitt

The important permanent-magnet alloys 15 years ago contained carbon and depended upon it for their permanent-magnet properties. In recent years great advances have been made in a number of new alloys substantially free of carbon. These include Remalloy,' an alloy of iron, cobalt, and molybdenum, the various iron-nickel-aluminum alloys of the Mishima2 type, and the more recent Alnico V3 in which the best properties are developed by heat-treating in a magnetic field. The Mishima and the Alnico types of alloys are very brittle and after casting must be ground to size. This article describes a permanent-magnet material4 that can be machined as cast, and when handled with some care can be rolled to thin sheet and drawn to fine wire. Optimum magnetic properties are developed by a simple heat-treatment, and at this time the ductility of the alloy disappears. If the cast alloy is heat-treated without cold-working the mag netic energy product is about 1.0 X 106. This material is called Vicalloy I (pronounced vicalloy, V for vanadium, I for iron, and C for cobalt). When the alloy is first hot-worked and then considerably reduced in area by cold-swaging, drawing or grooved rolling, it is found that after heat-treatment the magnetic energy product measured in the direction of previous extension can be increased to 2.0 to 3.5 X 106. These higher values have been obtained only after reductions in area of 75 to 95 per cent, and since the material hardens considerably during working, the reduction ordinarily can be accomplished only in fine wires, although larger sizes can be reduced by the use of powerful machinery. When the material has been cold-worked in such a manner as to improve its energy product substantially, it is called Vicalloy 11. Commercial use of Vicalloy has been made in the recording of speech. Tape 0.002 by 0.050 in. has been found superior in quality to all others tried, and is now used in the Western Electric Mirrorphone 5 In a variety of forms Vicalloy I or I1 is useful in many laboratory instruments, and in experiments in which the sizes and shapes required cannot be obtained with the other more brittle permanent-magnet materials. In 1936, during a study of other age-hardening magnetic systems, it occurred to the author that some of the iron-cobalt-vanadium alloys might be suitable for permanent magnets. The proportions of iron, cobalt, and vanadium were varied and a range of alloys of particular interest was found, as shown by the indicated area in Fig. I. The limits of this range of composition are 30 to 52 per cent iron, 36 to 62 per cent cobalt, and 4 to 16 per cent vanadium. The compositions indicated by points outside this area were also tested. Preparation and Properties OF Vicalloy I The alloys were usually cast in graphite molds into bars 3/4 in. in diameter and

Jan 1, 1946

By Donald W. Scott

Generally speaking, there is nothing very difficult about taking good microgrztphs of photogenic thin sections or grains with a petrographic microscope-camera setup. However, sometimes it is desired to show some detail that cannot be illustrated satisfactorily by the usual micrographs taken with parallel polarized light, with crossed nicols, or even with two micrographs. A simple procedure giving good results has been used at Battelle Memorial Institute for subjects falling into this classification, and it is believed to be of interest, especially to research people who must sell a point to executives through the medium of well-illustrated reports. The following problem illustrates a typical application: It is desired to photograph a thin section of an iron ore to illustrate the character and association of the iron oxides and the individual quartz crystals. A magnification of 75 dia. is acceptable. A micrograph of the field in question (Fig. Ia) was taken with parallel polarized light. Due precaution was taken to provide critical illumination, correct exposure, a sharp focus, a good darkroom technique, and other essential conditions. It illustrates correctly the iron oxides, but it fails to show the individual quartz crystals. A micrograph of the identical field (Fig. Ib) was taken under the same precise conditions, but with crossed nicols. It gives a better idea of the character of the individual quartz crystals but is likely to be misinterpreted unless accompanied by a lengthy descriptive note. This micrograph suggests that the centrally located, large black area is composed entirely of iron oxides. That this' is an incorrect interpretation is evident by reexamining the micrograph of Fig. Ia. The correct interpretation is that the dark area contains quartz crystals oriented with their optical directions parallel to, or nearly parallel to, the vibration directions of the polarizer and analyzer of the microscope. Thus, the executive, or anyone who had not done the work personally, would get no more than a fair interpretation, even if two micrographs were included; and in the interests of both brevity and clarity, one micrograph usually is more desirable. Exactly how many quartz crystals occur in this region cannot be told from the two micrographs, and a printing of the two negatives in register would likewise not show the detail desired. Thus, it is evident that some subjects cannot be satisfactorily illustrated by the usual procedures. In photographing Fig. Ic the light was subdued and, during the entire exposure of 75 sec., the analyzer nicol was rotated uniformly in its mounting from a crossed position to 45° uncrossed position to introduce the desired amount of contrast in the various individual quartz crystals. The true reproduction of the character and association of the iron oxides, and the additional structure and detail in the quartz areas, is apparent. It might be

Jan 1, 1949

By Edward Sampson, Allan B. Griggs

Surveying of many holes drilled by the U. S. Bureau of Mines in the Metaline district has shown surprising deviations. The holes start in the Ledbetter slate (Ordovician) and pass into the underlying gently dipping Metaline limestone (Cambrian) at varying depths, locally in excess of 1000 it. All holes start vertical, but one had deflected as much as 35° at a depth of only 300 it. One hole was found to be deflected 70' at a depth of 1000 ft. These deviations were not indicated to the drillers by any action of the rods or machines. Analysis of the survey data in the light of the observed geology indicates that the holes deviate most in the Ledbetter slate and scarcely at all in the Metaline limestone. The upper part of the "limestone'" in most holes is a massive rock strongly altered by hydrothermal action and essentially homogeneous. The slate is only obscurely bedded but has a cleavage, varying from slight to strong, which is unrelated to bedding. Drill holes have deflected to become nearly perpendicular to the cleavage. Several plans and cross sections are submitted showing the behavior of various holes. Introduction The Metaline district of northeastern Washington has received much attention recently and has promise of becoming even more important as a source of zinc than at present. Exploration has been conducted largely by deep diamond drilling, and in the course of this work it was found that holes became seriously deflected. This paper deals with the nature and causes of these deflections. The district lies along the Pend Oreille River in the northeastern corner of Washington, about loo miles north of Spokane, 9 miles from British Columbia, and 15 miles from Idaho. Three mines are now in operation and for a number of years have furnished a considerable production of zinc and lead. The ore contains zinc and lead in a ratio of about 31/2 to I, and occurs in the upper part of the Metaline limestone of Cambrian age, the upper member of which, where unaltered, is a rather pure limestone. This is overlain by Ledbetter slate of Ordovician age. Ore has formed by replacement of limestone, commonly 100 to 200 ft. below the slate, in areas of gentle dip, resulting in extensive tabular ore bodies. In and near ore, limestone has been intensely altered to granular dolomite and fine-grained quartz, which, where it predominates, forms "jasperoid." As part of their war program, the Geological survey and Bureau of Mines of the U. S. Department of Interior have been cooperating in an investigation of the district. The exploration by the Bureau of Mines in 1943 and 1944 was conducted largely by deep diamond drilling in which as much as 1000 ft. or more of Ledbetter slate was penetrated before the ore-bearing Metalin-2 limestone was reached. During the course of this drilling it was found that holes were seriously deflected while traversing the Ledbetter slate.

Jan 1, 1949

By Richard H. Willey

Efficient handling of large tonnages in open-pit mining demands, primarily, an abundance of well fragmented rock. To accomplish this, a drilling and blasting department composed of a well-knit, versatile group of workers and supervisors must be established. Some costs will remain relatively on the same level over a period of years, while others can be greatly lowered as will be shown. 'The Utah Copper Division, Kennecott Copper Corp., Bingham Canyon, Utah, has been ever alert for improvements in operating methods and equipment to gain increased efficiency and lower costs. Bingham Canyon MIne The greatest dimension of the mine is 8000 ft northeast-southwest with a width of 5000 ft southeast-northwest. From the lowest level, at an elevation of 6040 ft above sea-level, the mountain rises in 27 benches on the west side to W level (elevation 7800 ft) and 21 benches on the east side to Q level (elevation 7460 ft). At the inception of open-pit mining in 1906, the overcapping of leached porphyry had to be removed to reach a commercial grade of sulphide ore. The overcapping or waste now remaining is quartzite with intercalated limestone beds. The limestones are usually soft in nature except in the south-middle portion of the mine where they have been meta-morphized along the contact zone. This area usually gives drilling and blasting operations a great deal of trouble. Here occurs the greatest amount of secondary blasting, as the well-established fracture planes cause the altered beds to break into large boulders. Several massive quartzite "ribs" occur in the overburden, and as a result, the uniform breakage is difficult to obtain. The major quartzite areas have been subjected to complex folding, fracturing and faulting because of the intrusion of the underlying stock. The monzonite porphyry, which carries the commercial values, presents no serious drilling problem because of its softness and extensive minute fracturing throughout the mass. A series of major slips or faults pass through the ore body which, although of considerable advantage to the drilling and blasting department, sometimes works to the disadvantage of the track department. Drilling an11 blasting of the porphyry apparently becomes easier as depth is attained. but highly siliceous streaks throughout the pit still present difficulties. At no place is the rock of such character as to allow excavation without preparations. On certain higher elevations or levels, old fill material can be dug by the shovels, but only at some risk to equipment because of bank slippage. Past Methods At the outset of shovel operations in 1906, drilling was done with the Ingersoll-Rand F-24 piston drill mounted on an un-

Jan 1, 1949

By J. C. McDonald

A DDITIONAL experimental data are presented in this note on a phenomenon which has been touched on but lightly in the literature. The common magnesium base rolling alloy (AZ31B) contains about 3 pet A1 and 1 pet Zn. When cold rolled, it hardens until it starts to break up in the rolls at 30 to 50 pet reduction. When it is heated after rolling to full hardness, it softens. However, other magnesium alloys have shown themselves capable of being cold rolled indefinitely, provided the ratio of roll diameter to starting gage is sufficiently high. As measured by the tensile test, these alloys actually soften when the reduction becomes large (60 to 90 pct). A subsequent heating at 300' to 500°F can produce hardening of this metal. Heating at higher temperatures (600' to 800°F) causes recrystalliza-tion and softening. Menzen' has shown that a magnesium base alloy can be cold rolled without intermediate anneals as much as 90 pet. The alloy studied, Mg-1.5 pet Mn, softened considerably between 20 and 90 pet reduction, as measured by tensile properties; a decrease in yield strength of 30 pet, and an increase in elongation from 3.2 to 16.7 pet (longitudinal direction of the sheet). However, Menzen gives no data on the reaction of this metal. to heating. Ansel and Betterton2 and Hurst and Hatch3 report a similar effect in Mg-1.5 pet Mn-0.1 pet Ca. Their data show an initial hardening, followed by softening. The former authors also show that the alloy softened by cold rolling will harden when heated at low temperatures, and that these effects are absent in Mg-3 pet Al-1 pet Zn. In the course of work4, 5 some years ago, the author observed similar effects with alloys containing cerium, thorium, or zirconium; but not with elements like aluminum, silver, or zinc. Table IA contains the results of an experiment which shows these effects rather well. A binary alloy with 0.3 pet total rare earths (Mischmetal* added) was rolled hot to 1/16 in. and then annealed to full softness by heating 30 min at 800°F. Rolling was continued at 1.5 pet per pass to 80 pet total reduction on 8 in. diam rolls. The metal was harder after 20 pet work than initially but, at 80 pet reduction, properties were back to their original values. Heating for 1 hr at 450°F produced about the same hardness whether the reduction was 20 or 80 pet. At intermediate reductions, the metal hardened, but not to as high values. Extensive cold rolling may also be carried out on metal hot rolled at temperatures sufficiently low to produce a semihard temper. Mg-0.6 pet Zr was rolled to 0.1 in. at 700° to 800°F, 30 pet per pass. As shown in Table IB, a further cold reduction of 85 pet, at 1.5 pet per pass, definitely softened the metal.

Jan 1, 1959

By H. M. Day, C. H. Mathewson

The constitution of the system silver-mercury has attracted the attention of many investigators during the last two decades, but since their results are for the most part in poor agreement, there is little need for a review of their individual contributions. It remained for the very careful thermal and microscopic investigation of Murphy1 in 1931 to give the constitutional diagram in its present and unquestioned form, which is shown in Fig. 1. He devised methods for taking cooling curves on alloys under high pressures and for the microscopic observation of alloys which contained liquid mercury as a structural constituent at ordinary temperatures. The compositions of the intermediate phases were confirmed and supplemented through X-ray analyses by Preston2 and Stenbeck.3 According to Murphy, at 2760 C. silver is able to dissolve 44 to 45 weight per cent of mercury, which may increase at lower temperatures to about 50 per cent. Preston concluded that the saturation boundary occurred at 46 ± 2 per cent at 100° C. From the values reported in the literature, these are the only ones that may be accepted as lying even in the right region. Preparation of Alloys The silver used in the present investigation was supplied by the United States Metals Refining Co. through the courtesy of the Committee on Industrial Uses of Silver and, since a complete spectrographic and chemical analysis was furnished, no attempt was made to purify it or to further establish the impurities present. The analyses reported by the company are shown in Table 1. Milligan4 has found that the magnesium content is probably less than 0.0005 per cent.

Jan 1, 1938

By A. J. Miles, A. D. Topping

in this paper, the theory of elasticity has been applied to the rock about a deep well, It is assumed that the rock has a modulus of . elasticity and a Poisson's ratio and that the theory of elasticity applies. It is necessary to know or assume the state of stress existing in the rock before it is penetrated by the well drill. The application of this theory indicates that stress concentration of shear, tensions, and compressions about the bore hole are of a high order. This is particularly true when a horizontal compressive stress exists in one direction only in the formation before drilling. If such an initial state of stress exists before drilling, then the rock will have stress concentrations of both tension and compression at the same elevation and of such magnitude that failure of the rock is likely. Accompanying these is a shearing stress of large proportion which is likely to produce spalling of the well walls. Internal pressure applied to the well bore will relieve the extreme compression but not the tension and has little effect upon the shear. Plastic deformation of the rock through a geological time tends to mitigate the stress concentrations. IntroductioN It has long been known that the stresses about holes and re-entrant corners of elastic solids under the influence of loads are different and generally more intense than those imposed upon the body else- where. Stress concentration at a re-entrant corner can be reduced by increasing the radius of the fillet at the corner. Stress concentration at the end of a crack in a plate undergoing either tension or compression Can be relieved appreciably by drilling a hole at the very end of the crack. Also, stresses can be increased in an elastic body in tension or compression by making a hole in it. The stress concentration is greatest at the edge of the hole. Considerable knowledge of the stresses which exist about the bore hole of a deep well may be had by applying our knowledge of engineering mechanics; or more particularly the theory of elasticity. It is, of course, necessary to make the assumption that the rock is elastic and behaves as an elastic solid, that is, that it obeys Hooke's law, has a modulus of elasticity, and a Poisson's ratio. It is also necessary to know, Or assume, the state of stress which exists in the rock prior to the penetration of the drill. With this knowledge it is possible to compute the stresses about the bore hole. The problem can be simplified by considering several simple cases separately and then by applying the principle of superposition to solve the more complex cases which are made up of the simpler ones. Case i—Rock Strata in Compression Penetrated by a Hole This case was first worked out by G. Kirsch* for structural material, but applies equally well to a horizontal rock strata in a state of in in one direction

Jan 1, 1949

By N. F. Fiore, M. C. Mangalick

DISLOCATION damping in single crystals is orientation dependent.&apos; If dislocations are distributed uniformly over all the slip systems in a crystal, and if each dislocation contributes identically to the damping process, then a damping loss or decrement 6 arises. In fact, however, for a crystal of axial direction (hkl), dislocations on certain slip systems are oriented to make a larger contribution to the damping loss than are dislocations on other slip systems. Thus the measuring damping, 6 (hkl) is proportional to an orientation factor (hkl), which weights the ability of each slip system in the crystal to contribute to the total damping. If it is assumed that dislocations are distributed uniformly on all slip systems, then for a given orientation of an fcc crystal this factor is determined2,3 by the three nonzero elastic constants Cll, C12, and C44 and the density p. In this communication measured values of elastic constants for two Fe-18Cr-Ni alloys are reported, and the dislocation damping results on two different orientations of each alloy are analyzed for orientation dependence. Elastic constants were determined by measuring the ultrasonic velocities of one longitudinal and two shear waves in (110) direction of the fcc crystals.4 Variation of velocities with the change in orientation is very small for (110) orientation,3 and so this direction is ideal for orientation factor and comparative damping measurements. Experimental Procedures. The nominal compositions of the alloys studied are given in Table I. These alloys were vacuum-melted and vacuum-cast from high-purity materials at U.S. Steel Applied Research Laboratories. The single crystals were grown by the modified Bridgeman technique. The specimens were homogenized at 1350°C for 20 hr, cut to shape and size with a spark cutter, and then annealed at 1100°C for 20 hr prior to use. In the KHz frequency range, the Marx composite piezoelectric oscillator was used to obtain the damping. The ultrasonic pulse technique was used to measure the ultrasonic velocities and the attenuation in the MHz frequency range. M.c.mANGALICK,-- StudentMemberAIME,formerly Research Assistant, University of Notre Dame, is now with Casting Laboratory, Chase Brass and Copper Co., Cleveland, Ohio. N. F. FIORE, Associate Member AIME, is Assistant Professor, Department of Metallurgical Engineering and Materials Science. University of Notre Dame, Notre Dame, Ind. This communication is part of a Ph.D. thesis presented by M. C. MANGALICK to the Graduate School of the University of Notre Dame. Manuscript submitted May 20. 1968. IMD Elastic Constants. Table I gives the values of the ultrasonic velocities. Values of C11, C12, and C44 calculated from these velocities are also given in Table I, and it is evident that there is very little variation in C11, C12, and C44 with nickel content. This slight variation may be attributed to inaccuracies in velocity measurements and practical differences in the orientations of the specimens. For example, in B the time interval for vl was 2.4 ± 0.05 sec giving an error in v1 of 0.235 x or 0.005 in. per sec. The elastic constants obtained by pulse technique were tested by calculating E<110>, Young&apos;s modulus for the (110) direction, from the equation: This value was compared with the value computed from the resonance bar measurements in which where fr is the resonance frequency and I, is the length of the specimen. In all cases, the values calculated from the ultrasonic velocity measurements

Jan 1, 1969

By Robert E. Allen

The organized curtailment of California oil production is not yet one year old but during its first year it has accomplished so much that it is now firmly established as an agency of economic efficiency. The principle of cooperative curtailment has been adopted by other states and it is safe to say that the principle will continue as long as the demand for petroleum is notably less than the potential production. It&apos; is interesting to note that this same principle of regulating supply to meet demand is now being urged for other industries, such as agriculture and mining. Since Oct. 31, 1929, when curtailment was instituted by the oil producers of Santa Fe Springs and Long Beach in an effort to avert the disaster of ruinously low prices which confronted them, there has been a constant and increasingly effective curtailment program in California. Prior to that time a notable effort toward the restriction of oil production was made under the direction of F. C. Van Deinse during the early summer months of 1929. A considerable reduction of oil output was recorded as the result of this effort, but because of incomplete cooperation and the discovery of still deeper zones at Santa Fe Springs the effort was abandoned; flush field production became unrestrained and prices soon fell to low levels. This initial curtailment movement was educational and experimental. It showed all operators a way out of their overproduction difficulties and developed the principles followed in later curtailment efforts. Thus it was that only a few days after their oil had been reduced to 60 c. per barrel, the operators of Santa Fe Springs got together and agreed to restrict their current production of more than 270,000 bbl. daily to not more than 150,000 bbl. daily. The operators at Long Beach followed the same course a few clays later and agreed to limit their production to not more than 110,000 bbl. daily. The Santa Fe Springs operators chose H. P. Grimm as umpire and director of their proration program. Neal H. Anderson was chosen umpire for Long Beach. Since that time, as the need for curtailment has increased, practically every field of the state has come under the curtailment of these two umpires. Curtailment of the Elwood and

Jan 1, 1931

By R. C. Mahon

THE Homer iron-ore mine is at Iron River, Mich. Because it covers a large area, 400 acres, and because there was a considerable depth of water in the glacial drift above most of the ore bodies, this mine has presented a number of unusual and often difficult operational problems. The purpose of this paper is to discuss a few of the most important problems encountered. SURFACE WATER Mining on this property was started on one 40-acre tract. The ledge in this area was the highest on the property and, although it was a real problem, water could be handled by underground pumping. During the first period of mining, drifts were driven just under the ledge and holes were drilled through to the surface material. In later years these drifts have been extended wherever possible. Although these drifts assisted in the drainage problem, it was evident they would not be sufficient alone. Before mining on a large scale could be started on this property, the water problem had to be solved. A number of test holes were put down to the ledge, and showed that there was an average 150 ft. of water-saturated glacial drift above the ledge over the rest of the mine. The upper 70 ft. was gravel and sand and the lower 80 ft. clay and hard pan, with some narrow seams of sand and gravel. It was evident that the water above the clay seam could not be drained off through openings in the ledge and for that reason it was decided to install surface drainage wells. This method of drainage was entirely new at that time and was pioneered at the Homer mine. The sinking of the first well was started in June 1929. Immediately following the first well a number of wells were sunk, but only to the top of the clay seam. This was done with the idea that a greater capacity could be obtained in a shorter time from gravel seams where the water flowed more freely and that the cost of pumping the water above the clay seam would be considerably less than if the wells had all been sunk to the ledge at once. Before the drainage of surface water was started, 1200 gal. per min. against a head of 800 ft. was being pumped from the mine. By March of 1932, with five surface wells in operation, the mine pumping had been reduced to 150 gal. per min. At this time we were pumping 5000 gal. per min., under an average head of 110 ft. from the surface wells. The total pumping costs were 30 per cent less than in 1929 because the greater capacity was being pumped at a much lower head. From 1932 to 1936 the mine was idle and all surface pumping was stopped. Since 1936, 10 new wells have been added with a total pumping capacity of 8000 gal. per min. at the present time. The water level has been lowered 70 ft. since surface pumping was started in 1929, and it is now approximately at the top of the clay. To remove the water below the clay seam, 11 of the 15 wells were sunk to the ledge.

Jan 1, 1945

By Loyd R. Kern

A procedure for determining the behavior of a reservoir under a gas or water injection program was reported by Buckley and Levertt in 1942.1 This method, which allowed the calculation of the phase saturation distribution behind the front of a displacing fluid, has been extended to apply to a more general situation. The reservoir may initially contain flowing quantities of the displacing fluid, or the fluid in the reservoir may be above saturation pressure SO that solution effects are present. Production may occur behind the front as in the case of a well which is produced after breakthrough of the displacing fluid. The calculating procedure is simplified in that the graphical integration necessary to determine breakthrough saturation is eliminated by performing a direct integration and the graphical differentiation necessary to determine saturation distribution is eliminated by representing the displacing phase fraction of the flowing stream by an empirical equation. This representation results in simple expressions for the producing gas or water/oil ratio and cumulative production. INTRODUCTION A method for the calculation of the saturation distribution behind the front (interface between the displaced and displacing phases in a gas injection or water flooding operation) was reported by Buckley and Leverett in 1942. The method leads to a curve for the saturation distribution which is double-valued; consequently, part of&apos; the curve was interpreted to be physically meaningless. That part of the curve which has physical significance was determined by a graphical integra-tion (material balance). In this paper it is shown that the integration may be performed analytically with a resulting equation for the saturation of the displacing phase at the front. The case in which the displacing fluid is initially flowing and the case in which the reservoir is initially above the saturation pressure so that some injected gas goes into solution are included in the integration. The calculations are considerably simplified by representing the fraction of the flowing stream which is oil by an exponential function of saturation. The methods is extended to apply approximately to reservoirs in which wells located between the injection well and the front are produced. An illustrative example utilizing the methods presented is included. RESERVOIR BELOW SATURATION PRESSURE In the case of a water flooding operation or in the case of a gas injection operation in which no gas goes into solution in the displaced oil, the equation for saturation in a linear flow system as a function of time and position as given by Buckley and Leverett is where* q = total reservoir volume flow rate, rvb/day A = cross sectional area of system, sq ft / = porosity of formation x = distance from injection point, ft t = time, days Pj = saturation of the displacing phase /dx velocity of planes of constant saturation, ft/day *The nomenclature used here is not the same as that used by Buckley and Leverett A complete nomenclature is given in Appendix A.

Jan 1, 1952

By R. W. Gurry

WHEN a steel in the austenitic state, with all its carbon in solution, is maintained, at constant temperature, in contact with a gas that removes the carbon from the surface, yet without otherwise altering the composition of the steel, the change in weight of the specimen, after any period of exposure, is a direct measure of the amount of carbon it has then lost. The purpose of the present paper is to show how, by application of established mathematical reasoning based on the fundamental diffusion law and on certain postulates, this loss of weight yields a complete picture of the distribution of carbon throughout a specimen of regular shape after any period of exposure, with all the accuracy required in any practical occurrence of decarburization. Precisely the same is true for the gain in weight during the reverse process of carburization, or for the gradual gain or loss of any element, so long as the steel comprises only a single phase at temperature, provided always that the experimental conditions conform to the postulates. The change in carbon content from surface to center of the specimen is always continuous, when everything is in solution, even though under the microscope the decarburized zone (or carburized rim) may appear to be sharply defined. The experimental procedure is described and some typical results are presented, which are then interpreted by application of the diffusion law. EXPERIMENTAL PROCEDURE Initially an endeavor was made to follow the gain of weight during the process of carburization in a hydrogen-toluene atmosphere, but it was soon found that the specimen became coated with graphite, which could not be removed without some loss of metal; therefore it was decided to continue carburization until the steel was saturated throughout, to remove all graphite from the surface of the specimen, and then to follow the loss of weight during decarburization in a moist hydrogen atmosphere at the same temperature as that used for carburizing. The carburizing procedure has been described in an earlier paper;1 it suffices to state here that the carburization lasted about 140 hr. at 760°C. (1760°F.) and 44 hr. at 1110°C. (2030°F.), these periods being long enough-on the basis of the calculations presented later-to ensure that the specimen was about 99.9 per cent saturated at each temperature. The specimen was a cylinder about 3.8 cm. long and 0.475 cm. in diameter; the materials were carbonyl iron, a commercial low-metalloid iron, and a steel with 3.6 per cent nickel and the usual proportion of other elements. The fully carburized specimen, after cooling at the top of the furnace tube, was placed in a lathe and sandpapered to remove all graphite; then the diameter was measured with a micrometer caliper, and the initial weighing (corresponding to complete saturation) was made. By means of a

Jan 1, 1942

By J. B. Austin, R. L. Rickett

MEASUREMENTS Of the rate of decomposition of austenite at constant temperature are commonly represented by plotting the percentage transformed on linear coordinates against time on either a linear or a logarithmic scale, a method that yields a curve that in shape resembles an integral sign (Fig. 1). A graph of this kind is not always convenient because extrapolation to the beginning or end of the transformation, or even interpolation, may be uncertain unless there are a large number of observations, which seldom happens; furthermore, the degree of consistency of a set of measurements is difficult to judge from such a curve. It is desirable therefore to find some mode of plotting, or even better to find a standard variety of graph paper, that gives a straight line instead of the integral shape. The straight line has many advantages; the number of readings required to fix the position of the curve is greatly reduced, interpolation is easy and rapid, extrapolation can be carried out with greater confidence and, finally, the consistency of the measurements is readily estimated from the scatter of the points. The last advantage is particularly valuable when the data are obtained by direct microscopic examination alone, because they are influenced by the skill of the observer in estimating the relative size of areas, possibly also by undetected inhomogeneity of the specimen. A search for ways of representing the observations as a straight line yielded two methods which are described in this paper. The paper also includes an account of some interesting relations brought to light in applying these methods to the available experimental data. Usually the best way to derive such a method of plotting is to base it on established principles of chemistry and physics, as has been done, for example, for the temperature variation of the equilibrium constant of a chemical reaction. But so little is known of the mechanism of the decomposition of austenite, and so little is available in the way of well established background for changes of this kind, that it is simpler to rely upon purely empirical means. The general plan therefore is to study existing data with a view to finding some function of the direct observations that will

Jan 1, 1938

By J. C. Cordell, C. F. Weinaug

A study of the behavior of retrograde condensation from gas mixtures was made in the presence and absence of sand in order to determine if the condensed liquid would re-vaporize in the Presence of sand. Methane-butane and methane-pentane mixtures that would form liquids by retrograde condensation when produced from a constant volume cell were used. The methane-butane mixtures of similar composition were produced by three different methods. The first two were charged into an empty cell and were produced in one case within a period of 9 hr and in the other within a period of 3 days. The third mixture was charged to a sand-packed cell and produced within a period of 9 hr. The curves relating composition of the produced gas to pressure obtained from these experiments show that equilibrium was maintained as long as liquid was condensing. However, during the portion of the pressure decline where the condensed liquid should be revaporizing, equilibrium was maintained only when the mixture was produced from the sand-packed cell. The methane-pentane mixture is produced only in the presence of sand. The data obtained for this system also show that equilibrium is maintained at all times during the pressure decline. These results indicate that revaporization is aided rather than prevented by the fact that the condensate "wets the sand." The significance to the petroleum industry of the behavior of hydrocarbons in the retrograde region is becoming increasingly important because a large percentage of reservoirs being discovered today arc of the gas-condensate type. The important characteristic of a gas-condensate reservoir is the retrograde condensation of a liquid phase throughout the reservoir if the pressure is allowed to decline. In order to prevent the loss of this retrograde liquid in some of these reservoirs, they are "cycled"; that is, the material produced from the reservoir is processed to remove the heavier hydrocarbons and the light fractions are returned to the reservoir to maintain the reservoir pressure. Another method of producing these reservoirs is Pressure depletion. There are other methods but they are not in general use. Although a large number of factors are involved in determining the optimum method of producing a reservoir, only the problem of whether the retrograde condensate resulting from pressure depletion will revaporize from sand at equilibrium conditions is considered in this paper. Also the data are limited to the methane-n-butane and the methane-n-pentane systerns at loo°F and one type of sand. Three types of tests were run in order to compare the revaporization of retrograde liquid formed in a cell with that formed in a sand-packed cell, and to establish the effect of time. The results of tests presented in this paper indicate that both time and the presence of sand promote the revaporization of

Jan 1, 1949

By C. Edwin Nighman

THE following is a description of the methods used in rescuing men and extinguishing the underground fire at the Pennsylvania mine, Butte, Mont. This fire, which cost the lives of 21 men, began about 9 p.m., Feb. 14, 1916, at or near a ventilating fan on the 1,200 air-shaft station. This shaft at that time was downcast, while the main hoisting shaft was upcast. Owing to the proximity of the fire to the air shaft, the air in the latter soon became heated, and as the fan on the level was not running¬the power having been cut off shortly after the outbreak&apos; of the fire-the aim&apos; shaft became upcast to the 300 level. At this point a blanket of cold air from the surface caused the smoke and gases to he drawn in on that level and carried down again through the workings to the 1,200. A short time after the discovery of the fire, water was turned down the air shaft through a series of pipes around the collar of the shaft, which caused the smoke to recede, below the 300, so that within 2 hr. it was possible to search that level for the missing men. From the above it will be apparent why the air shaft was upcast instead of downcast as under normal conditions, and why men were suffocated at considerable distances from the seat of the fire. The smoke and gases that came up the main hoisting shaft did not diffuse through the workings to any extent. There are doors on all levels in the connections to the main hoisting and air shafts, but-in the confusion and running around many of these doors were left open, and this undoubtedly caused the smoke and gases to spread more rapidly than they would otherwise have done. It was necessary for most of the men on the various levels to pass close to the air shaft in going to the hoisting shaft, and when they encountered the smoke and gases in that vicinity a number turned hack and climbed down with the direction of the air currents and were then suffocated, while all those who passed through the relatively short pall of smoke to the main shaft were saved.

Jan 2, 1917

By W. A. West

One who attempts to collect and classify equilibrium data from various iron-alloy systems is soon struck with the absence of any quantitative theory that can serve as a general background against which to compare and contrast results from different systems, at different temperatures, and with different concentrations. It is not necessary to wait for a perfect theory; investigation of divergences of theory from observation may prove of great value in acquiring understanding of the subject. For example, one has only to think of Raoult&apos;s law as applied to aqueous solutions. The equations developed by Zener1 represent an effort to provide such a quantitative theoretical background, and it is therefore desirable to subject this theory to such tests as can be applied. The present article is intended to be an application of available tests, and may thus be considered as a supplement to Zener&apos;s paper. It is assumed that this paper is available to the reader. The equations make it possible to calculate the effect on the equilibrium concentration of one alloying element due to the presence of one or more other elements. In particular. they are intended to give, for alloy steels, the carbon concentrations in alpha and gamma phases in equilibrium with each other, and in gamma in equilibrium with cementite. They may, however, be modified for use for carbon-free alloys. A summary is given later of the equations used in analyzing the data in this paper, and the symbols are there defined. About 125 papers have been examined for experimental data suitable for this investigation. An effort was made to look up all available reports of ternary systems including iron and carbon, as well as similar systems of higher order. Supplementary material was also obtained from a number of binary systems. A few noncarbon ternary systems were also found to which these methods could be applied. A comparatively small proportion oi the papers read provided usable material. In many systems the number of quantitative observations made in the iron-rich region is extremely small, and the smoothed curves to be found in most published phase diagrams are entirely useless for quantitative treatment. This opinion is confirmed by the authors of the series on Alloys of Iron Research, whose remarks show clearly that they have no illusions as to the accuracy of many diagrams that they present. A further difficulty arises from the fact that these equations apply only to rather low percentages of alloying elements. The result is that at the lowest concentrations, where the best agreement might be hoped for, the errors of observation become relatively very large. The experimental difficulties in measurements of this kind of equilibrium are, of course, an old story.

Jan 1, 1947