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By N. Mungan, F. W. Smith, J. L. Thompson

Adsorption of polymers and transport, rheology and oil recovery efficiency of their solutions were studied in the laboratory to evaluate the use of polymers in waterflood-ing. While a tenfold mobility reduction was obtained with polymer concentrations as low as 0.05 per cent by weight, the mobility reduction depended on the type of polymer, molecular weight, salinity and pH of water, crude oil and capillary properties of the porous media. Choice of a suitable polymer and a workable concentration will have to be tailored for each application. Little reduction in the residual oil saturation can be expected from polymer flooding. Improvement in the volumetric sweep efficiency is possible hut the extent of the improvement can best be evaluated by properly designed field testing. Some aspects of the field use of polymer floods are discussed. INTRODUCTION Waterflooding is a simple, inexpensive secondary recovery method and is being used widely. Innumerable laboratory studies have been made to unravel the fundamentals of the displacement of oil by water and to find the ways of most efficient oil recovery. These studies and a great many field case histories have revealed that the prime cause of poor oil recovery is the inefficient and incomplete sweep of reservoir volume by the injected water. Sweep efficiency is affected by many factors of which the mobility ratio is an important one. Mobility ratio M is defined here as the ratio of water to oil mobilities: M = (k»/y,r)/(k,JJJJ........(1) In Eq. I, the permeabilities are the effective permeabilities and depend on fluid saturations and, hence, change during the different depletion stages in a flood. A wide practice is to use the effective water permeability at residual oil saturation and the effective oil permeability at interstitial water saturation in Eq. 1. If the mobility ratio is greater than one, the mobility ratio is unfavorable and water, being more mobile than oil, would finger through the oil zone resulting in poor oil recovery efficiency. If the mobility ratio is favorable (one or less) the displacement of oil by water occurs more or less in a pistonlike fashion. In some waterfloods. the mobility ratio is unfavorable and any additives by which the mobility of water can be decreased would favor more efficient oil recovery. The thing to bear in mind, however, is whether or not the improvement in oil recovery is sufficient to more than pay out the cost of the additives needed. For example, materials like sugars, alcohols and glycerine reduce water mobility by thickening the water, but the cost of material requirement precludes any field application. For an additive to be useful in water-flooding, it must bring about a large reduction in water mobility at low concentrations; it must be adsorbed only negligibly; and it must not completely plug up the formation. Some synthetic organic polymers have shown promise of meeting these requirements and have been used in the field.'-W owever, no in-depth studies of the rheological, adsorption and oil displacement characteristics of polymer solutions have been reported. The present work is a study of these properties. EXPERIMENTAL In this work, concentrations are given on a weight per volume basis; 0.5 per cent concentration means 0.5 gm of polymer is dissolved in enough water (or NaCl solution) to make 100 ml. A bactericide, usually 0.1 to 0.2 per cent by volume of 38 per cent formaldehyde solution, was used in the polymer solutions. The NaCl solution was 30,000 ppm. Some properties of the polymers studied are given in Table I. Physical properties of all cores used are in Table 2. Flow behavior of polymer solutions was studied by three consecutive flow tests in cores. First, water (or brine) was injected at constant rate of about 1 ft/D to obtain the water mobility. Then, filtered polymer solution (prepared in water or brine) was flowed through the core. Since the rate was constant, increase in the pressure drop across the core reflects decrease in the mobility. Finally, the core was flooded with water (or brine) to study recovery of mobility. The Alundum cores which were used in

Jan 1, 1967

By Jesus P. Manzano

The report of which this paper is a summary was made in 1890 for the Compania Investigadora Mexicana y Americana. Since the region examined covers 900 sq. kilom., chiefly of wooded arid rocky hills, almost without roads, and for the most part uninhabited, While the examination had to be made in two months, of which period more than 15 days were continuously rainy, I need not say that this account is not complete and thorough. I. Geography and Topography. The center of this zone, 19 kilom. SW. of San Luis Potosi, is situated in lat. 21° 24' N., and long. 2° 3' W. of Mexico City. The altitude ranges from 1866 m. (that of San Luis) to . 2816 m. (that of the Realito mountain), in the Sierra de Sail Luis. The topography is hilly—partly wooded, partly bare. The principal more level areas are the Bledos valley on the south, and portions of the haciendas of Tepetates, San Fran cisco and Santiago, on the west. The water-supply is scanty. The two streams that cross the Zone, the Santiago and Bledos rivers, carry water nearly the year through, though much reduced in the dry season. Other streams are torrents of less importance. All the waters of the valley and Sierra of Sail Luis arc absorbed or sink, not passing beyond Soledad de los Ranchos. The Continental di vide is within the Zone, some waters going west to the Pacific, others east to the Gulf of Mexico. II. Geology. Concerning the geology of this district I condense the fol lowing from the memoir, Las Minas de Guanajuato, prepared for the Minister of Fomento by Senor Pedro Lopez Monroy, mining engineer, with which I am entirely in accord. He says, ill substance:

Jan 1, 1902

By J. P. Hirth, A. H. Clauer

A simple graphical method is presented for the determination of climb forces on dislocations exerted by uniaxial stresses. In conjunction with standard stereographic projections, the technique is applicable for any crystal system. Climb forces on glide dislocations in bcc crystals are determined as an application. In connection with a study1 of elevated temperature creep of molybdenum single crystals, a detailed analysis of the climb force on a dislocation was necessary. In general, such forces can be calculated for an arbitrary dislocation segment from the Peach-Koehler equation2 (or one of its variants3"6) where Fk are the components of the force per unit length of dislocation line, ?i of the unit sense vector tangent to the line, ojl of the stress tensor, bl of the dislocation Burgers vector, and is the Einstein permutation operator with components ?123 = ?231 = ?321 = —?132 = — ?321 = —?—213 = unity, and all other components zero. It is understood in the suffix notation of Eq. [I.] that repeated indices are to be summed over 1, 2, and 3. For the most general coordinate system, the matrix manipulations required to solve Eq. [I] are fairly complex. However, a simplification can be achieved by specifying a coordinate system based on the dislocation in question. The pertinent system involves cartesian coordinates xi, x;, xi, with attendant unit vectors e'i; ei being parallel to the Burgers vector b, and e'3; being parallel to the climb directions (b x ?), i.e., normal to the slip plane. In this coordnate system b = (bi, 0, 0) and ? = (?'1,?'2, 0). Hence, Eq. [I] yields for the climb force per unit length F3 = ?'2s'11b'1—?'1s'12b'1 [2] The first term on the right side of Eq. [2] is the climb force on the edge component of the dislocation, while the second is the (cross-slip) force normal to the glide plane acting on the screw component. Thus, the problem of determining the climb force reduces to that of resolving the stress components —il and s'12 in the xi coordinate system. Several authors7- l0 have shown, for the glide case, that such stress resolution can be performed most readily by graphical methods. Therefore, we present a similar method for the climb case. Of the suggested methods, we follow that of Hartley and Hirth,9 which can be performed directly with a standard stereographic projection for the crystal system in question. We treat the case of simple tension, or compression, this being the most common creep test in which climb is important. A set of cartesian coordinates (x1, x2, x3) is fixed with x3 parallel to the specimen axis. This set is connected to the x'i set by the factors defined in Table I. A perspective view of the coordinate systems relating them to the glide ellipse, is given in Fig. 1, while a stereographic projection of the coordinate systems is presented in Fig. 2. The transformation matrix connecting the xi and xi coordinates is x'i =aijXj [3] where an a11 a13 aij = a21 a22 a23 a31 a23 [4] s The corresponding transformation for the stresses is i [5] The only nonzero component of okl for the simple tension case is s33,. Hence, using Eqs. [4] and 151, we find that Eq. [2] becomes F3 = b'1s33 sin2 cos ?[cos ? sin a - sin ? cos a] [6] = m1b'1s033 sin a- rn2b's33 cos a where sin a = 5: and cos a = ?i, with a the angle measured from b to ?, i.e., a polar angle in the x1, x2 plane. The same equation with a sign change applies for compression. A graphical plot of the "Schmid" factor m1, relating to the climb force on the edge component, is presented in the stereographic projection of Fig. 3. In this projection the glide plane normal points toward the top of the page and the glide direction points normal to the plane of the page. To use the graph, one

Jan 1, 1970

By William Copp

THE SEAL BEACH oil field is between the Long Beach and Huntington Beach oil fields, south of Los Angeles, and about half the productive area is with-in the city limits of Long Beach. The proved area lies in portions of Sections 2, 3 and 11, T. 5 S., R. 12 W., S. B. B. & M. Seal Beach is 'an additional link in that remarkable chain, of oil fields extending from Newport to Beverly . Hills, filling in one of the few remaining gaps. It differs from other fields along this line of folding in that it is an oil field in an area of tide lands. Ocean-connected sloughs have access to this area, which ac-counts for its extensive mud flats. The surface eleva-tion of the low ground varies from 2 to 5 ft. above sea-level. This condition called for much preliminary work in building roads prior to field development. Roads are constructed with dredges and drag-line scrapers, which excavate mud from alongside the proposed road and pile it up to a grade high enough to be above high tide. The road bed is then surfaced with gravel, or decom-posed granite, which makes it serviceable in all kinds of weather. An immense amount of road material has already been hauled into this field. Well locations are staked in the mud flats, sometimes ahead of road build-ing, and material is dragged to its place on the ground by tractor. It is necessary to drive piling to support derrick foundations. The present practice is to drive 5 piles for each derrick leg, 4 under the rotary table, 2 under the draw-works, 2 under the Samson post and 4 under the pipe rack, a total of 32 piles. This pro-cedure is, of course, varied to suit special conditions, using either more or less piling.

Jan 6, 1927

By E. S. Wheeler

The rapid increase in the use of monel metal and malleable nickel in the form of sheet, rod and tube has resulted in a similar increase in the demand for these metals in the form of castings. These castings range in size from small valves and pipe fittings weighing a few ounces to large centrifugal pumps, gate valves and marine propellers, some of the last weighing as much as 24,000 lb. A group of such castings is shown in Fig. 1. A large nickel agitator is shown in Fig. 2. Monel metal castings are widely used in accessories for steam power plants and in a variety of chemical plant equipment where the corrosion resistance, high strength and toughness characteristic of this metal render it particularly valuable. Nickel castings find extensive use in the construction of corrosion-resistant apparatus, and are often used in conjunction with wrought nickel sheet and tube in the fabrication of equipment for handling a variety of chemical and food products, particularly dairy products. In response to this demand for castings, numerous foundries have undertaken the production of castings of these metals and have met with varying degrees of success. The successful production of castings of monel metal and nickel requires careful attention to molding practice, proper melting equipment

Jan 1, 1930

By J. Weertman

The paper of Gifkins and Snowden considers the interesting but difficult problem of determining the stress dependence of secondary (steady-state) creep at low stresses. These authors have concluded that at stresses below 250 psi (2 x 107 dynes per sq cm) the secondary creep rate of lead is proportional to the stress (viscous creep) and is not proportional to the stress raised to about a fifth power. The experimental data considered by them were obtained on tests conducted at room temperature and at 50°C. The lowest stress employed was 50 psi (3.5 X 106 dynes per sq cm). The authors pointed out the main difficulty in determining the stress dependence of creep at low stresses. The creep tests must be run for very long lengths of time. However they made no estimates of when an experimental creep rate determination must be rejected because it does not represent a true steady-state or minimum creep rate. In order to be certain that a creep curve is within the steady-state region, the total creep strain should be of the order of 0.1 to 0.2. For a creep test of a year's duration this requirement implies that a secondary creep rate smaller than about 10-3 per hr cannot be measured reliably. The corresponding creep rate for a 10-year test is 10-6 per hr. The creep rates of the tests that were considered by the authors to prove the existence of viscous creep were of the order of or less than 10-6 per hr. One can conclude reasonably that this data does not prove unambiguously that large strain steady-state creep rate of lead is proportional to the stress in the stress range of 50 to 250 psi (3.5 x 106 to 2 X 107 dynes per sq cm). Another technique can be used to obtain the stress dependence at low stress levels. The creep rate is a very sensitive function of temperature. The creep rate can be increased by very large amounts merely by increasing the temperature. We carried out steady-state creep tests on lead single crystals25 at temperatures up to 320°C. We were able to obtain creep rate data down to stresses as low as 35 psi (2.5 x 10' dynes per sq cm). Our smallest creep rate was 8 x 10-5 per hr. Thus we obtained large strain, steady-state creep rates to even lower stresses than were considered by Gifkins and Snowden. No evidence was seen for viscous creep. The creep rate was proportional to the stress raised to about a 4.5 power down to the lowest stresses. Since there is no reason to believe that changing the temperature should change the stress dependence of steady-state creep, we feel that large strain viscous creep does not occur in the stress range quoted by the authors for lead single crystals or large-grain polycrystalline samples of lead. This conclusion does not imply that viscous creep may nat occur in a lower stress range or in the same stress range for fine grain material or at creep strains very much smaller than 0.1. Support by the U.S. Office of Naval Research is acknowledged. Authors' Reply R. C. Gifkins and K. U. Snowden We thank Dr. Weertman for his discussion and although, as we hope to show, we do not agree with his reservations, we do concur in stressing the importance of ensuring that creep rates are reliably obtained. Dr. Weertman appears to be content to accept n = 1 for low stresses with fine-grained material but not for single crystals. We believe our results show that the former result cannot be accepted without also accepting the latter. We will also show that the probable errors in our minimum creep rates are insufficient to alter our conclusions, that the criterion proposed by Dr. Weertman is arbitrarily restrictive and his alternative experimental approach possibly invalid. 1) A principal result of our Fig. 1(a) is that n = 1 for polycrystalline specimens at room temperature and 50°C for stresses below -250 psi. There was evidence that crystal slip and grain boundary sliding contributed approximately equaily to the overall strain in this low-stress regime. This implies that either a) grain boundary sliding controls slip within the grains or b) both grain boundary sliding and crystal slip independently occur according to mechanisms which give n = 1. Alternative a does not seem acceptable, so we were forced to consider b. This led us to reexamine work on bicrystals by Strutt and Gifkins and plot curves Fig. l(b). Previously Strutt et al. (loc. cit.), had merged these points with others using the Zener-Holloman parameter and thus, we now believe, had been led to overlook the behavior where n = 1. Curves C and D in Fig. l(b) did appear to confirm the hypotheses that n = 1 for crystal slip at these low stresses and the sliding curve F was similarly of the expected form. It was comparatively easy to find a quantitative theory to account for n = 1 for sliding and the similarity of curves C and D to curve F (all obtained from the same set of specimens) led us to feel that the single-crystal curves were valid. 2) We believe the secondary creep rates for both the polycrystalline and single-crystal specimens to be in error by factors c2. In Fig. 6 creep curves for polycrystalline specimens of lead(1) and lead(II) are reproduced as curves a and b, respectively, and curve c is for a single crystal at 100 psi. It is clear that, although the attainment of secondary creep rate takes 2 years for a and 150 days for b, thereafter the curve is linear for periods of 7 and -1 year, respectively. The single crystal has a linear portion commencing after 20 and extending to 90 days. Creep extension was measured directly using a traveling microscope reading to 0.01 mm on gage lengths marked on the specimens; the gage lengths

Jan 1, 1968

By C. Dinis da Gama

Because of the growing importance of back analysis for the interpretation of rock slope failures, particularly in open pit mines, it is suggested a methodologic sequence of activities for dealing with those problems. The principal mathematical tools for the interpretation of the most common mechanisms of slope failures are reviewed, including methods of stress and strain analysis, which seem to be more powerful for parametrization studies, and for developing more realistic explanations of slope behaviour, such as the measurement of displacements. An application of those methods is described, using slope failures detected in a Brazilian uranium mine (Cercado), thus providing reliable shearing strength parameters for the rock mass discontinuites, which were used in the final pit design. The concept of using backanalysis results to supply input data for pit design was implemented by means of the excavation of an experimental trench within mine limits, where specific instruments were installed, and several slope failures were monitored and backanalysed, in order to yield information about sliding mechanisms in the future open pit.

Jan 1, 1983

By Rex O. McLellan

The formation of a monovacancy in a metal is simulated in an elastic model by the displacement of the surface of a small spherical cavity in a large elastic continuum. The application of linear elasticity to this distortion results in a well- known formula for the energy and an expression for the concomitant entropy change due both to the shear strain in the continuum and also to the dilation of the solid resulting from the boundary conditions at the surface of the solid. Elastic data (the sliear modulus and its temperature coelficient) are used to calculate the entropy and energy of formation for many metals. Despite the simplicity of the assumptions involved, the agreement between the calculated entropies and energies and experimental values is remarkably good. In recent years there has been a large increase in measurements of the absolute concentration of mono-vacancies in metals as a function of temperature. Hence new data for both the energy and the noncon-figurational entropy of formation of monovacancies has become available. Recent measurements&apos; of the anomalous (non-Arrhenius) self-diffusion in many bcc metals has also focused interest on the prediction of the thermodynamic parameters of mono- and multi-vacancies in those metals for which no data are available. Damask and Dienes&apos; have discussed the various theoretical calculations of the energy of formation EL, of a monovacancy. These include simple models involving the breaking of atomic bonds on moving atoms from the interior of a crystal to the surface, models combining elastic calculations with surface-energy terms and detailed quantum mechanical calculations. The simler models give the correct order of magnitude of &, but tend to overestimate it by a factor of about two. The quantum mechanical calculations4"7 have been carried out for the noble and alkali metals with generally reasonably good agreement with the available Ef data. The calculation of entropy of formation Sfv14 lnvolves a fundamental calculation of the perturbation of the phonon spectrum caused by the creation of a vacancy. Huntington, Shirn. and wajda8 have given an approximate evaluation of sJV by considering an Einstein model for the localized vibrations in the immediate neighborhood of the defect and then using elastic theory to calculate the entropy associated with the shear stress field in the distorted crystal (as originally proposed by Zenerg). They also included a term due to the dilation of the crystal. They obtained a value of 1.47k for copper, in good agreement with the experimental value (1.50k). However, Nardelli and Tetta- manzi1° have recently shown that neglecting the coupling between atoms (Einstein Model) may lead to a serious error so the agreement may be somewhat fortuitous. In this work simple linear elastic theory is used to calculate the entropy and energy of formation of mono-vacancies. Despite the simplicity of some of the assumptions involved, the agreement with the available experimental data is remarkable. However. the reasonable degree of success in the application of linear elastic calculations to the excess entropy of a solute atom in a dilute solid solution1&apos; indicates that the application of elastic theory to vacancies. where the interaction of different atomic species is not involved, may not be inappropriate. THE ELASTIC MODEL The metal is assumed to be a spherical elastic continuum. A small spherical cavity of volume V = 4i;v:&apos;/3 is cut from the center. removed. and dissolved rever-sibly in the bulk of the material. TO a good approximation no net atomic bonds are broken and the material does not undergo a volume change although the externally measured volume of the body would increase by V. The radius of the sphere of metal is much larger than r Next a negative pressure is applied to the cavity causing its surface to be displaced inward by an amount simulating the relaxation of the lattice around a monovacancy. In this model the energy and entropy accompanying the distortion are taken as 4, and <. As a first approximation the equation of state for the solid is taken as: r = ro(i + *~D LiJ where K is the bulk modulus. P the hydrostatic pressure. Vo the volume of the material at 0°K and zero pressure. and d+/dT = 30. where 0 is the linear thermal expansion coefficient. The variation of entropy with hydrostatic pressure is given by the Maxwell equation: These equations give the entropy change resulting from increasing the hydrostatic pressure from 0 to P as: and since • we have: This is the entropy arising from the dilation resulting

Jan 1, 1970

By I. Cadoff, E. Miller, K. Komarek

Jan 1, 1960

By R. G. Aspden

The cold rolling and annealing textures were studied for 3 pct Si-Fe grains initially (001) [hkl]. A concentration of (001) [loo] primaries were observed only in the annealing textures of crystals initially having [loo] within 8 deg of the rolling direction. Eke annealing textures of the (001) [I101 cold rolling textures were sensitive to the initial orientation of the grains. Single crystal data were used to explain the formation of (001) [loo] in poly-crystalline malerial. CUBE texture formation in 3 pet Si-Fe sheet occurs during the final high temperature anneal. Its formation is dependent on the proper distribution of (001) plane primaries with reference to the rolling direction&apos; and on the growth of these primaries by secondary recrystallization. The selective driving force for these primaries with (001) within 7 deg of rolling plane is derived from the difference in surface energy between the annealing atmosphere and the crystallographic planes exposed at the surface of the sheet.&apos;-= The alignment of [loo] directions of (001) secondaries with the rolling direction is required for optimum magnetic characteristics7 and is dependent on processing.&apos; A high degree of alignment has been observed when the final cold rolled texture has a strong (111) [ll2] type component3 and the normal grain growth texture prior to secondary recrystallization has components with a [loo] parallel to the rolling direction and planes from (001) to (110) parallel to the rolling plane.1,3,8,9 Generally, this (001) component is much weaker than the (110) component. The growth rate of (001) plane primaries to secondaries has been found to be independent of the orientation of the primaries with reference to the rolling direction, i.e., the secondaries have the same degree of alignment of [loo] directions with the rolling direction as the (001) primaries.&apos; Hence, the rolling and annealing textures of individual grains or single crystals are of interest in understanding the development of the (001) [loo] secondary recrystallization texture. (001) components have been observed in the annealing textures of cold rolled grains initially having a [loo] parallel to the rolling direction and an (001) rotated up to 30 deg from the rolling plane. Crystals initially near the (001) [loo] orientation when rolled under the influence of constraints imposed by neighboring grains form deformation bands and ro- tate in both directions toward (001) <110>.10,11 Deformation bands have been reported also for crystals initially with an (001) within 1 deg of the rolling plane and a [loo] within 1 deg of the rolling direction when rolled as a free single crystal.12 These crystals have weak recrystallization textures and contain near an (001) [loo] component.10-12 When near (001) [loo] crystals are rolled as free single crystals no deformation bands form and the crystals rotate by a single rotation toward (001) [110]. Recrystallization after a 70 pct cold reduction yielded near an (001) [loo] component13 and after a 90 pct cold reduction an (001) [I201 component." Crystals initially near (210) [001] had a texture after a reduction of 70 and 84 pct which was similar to the (111) [li2] but rotated 10 to 15 deg in the transverse direction. These crystals recrystallize to (210) [OOl] or (410) [001] and contain an (001) [loo] component.10,13 An (001) component has not been detected in the normal grain growth textures of other single crystals. Crystals initially having orientations between (110) [001] and (111) [ll2] have a cold rolled texture of principally (111) [ll2] .10>16 Other crystals with a [I101 parallel to the cross direction rotate to (111) [112] and/or (001) [110] stable end orientations. Crystals initially having from (001) [110] to (111) [lie] retain this orientation after cold rolling.15 The cold rolled textures having [I101 directions parallel to the rolling direction had components in the annealing textures related to the deformation textures by 25 to 30 deg rotations about common (1 10) poles. Cold rolled textures of the (111) (112) type recrys-tallized to (120) [001] or (110) [00l]. The purpose of the present work was to further the understanding of the alignment of [loo] directions of (001) secondaries with the rolling direction. The cold rolling and annealing textures of grains initially (001) [hkl] were studied. These data were applied to the formation of (001) [loo] by secondary recrystallization. PROCEDURES AND EXPERIMENTAL TECHNIQUES The (001) poles near the sheet normal and rolling direction are given in Fig. 1 for the 10 grains studied. Each of these grains was located in the center of a polycrystalline specimen approximately 25 mm wide and 50 mm long. The lower case lettered grains, a through dl were about 1.2 mm in diam and near the (001) [loo] orientation. Specimens containing these grains were from a commercial 3 pct Si-Fe alloy with the principle orientation of (110) [001] as obtained by impurity inhibition of growth with manganese sulfide inclusions.17,18 Upper case lettered grains, A through F, were about 6 mm in diam and had (001) planes near the rolling plane and [hkl] di-

Jan 1, 1963

By H. H. Waller, D. L. Monroe, D. P. R. Smyth

ORIGINALLY slusher drift development was conventional, advancing the drift full 10x13-ft size at 6 ft per round. This proved dangerous and costly because the weak fractured rock of the orebody cannot be left raw for any length of time without its reacting with air to cause spalling. With this method of drift development ground conditions were worsened by many blasts and the length of time it was necessary for the drift to remain open. The problem was practically solved by driving 5x7-ft pilot drifts, then enlarging to 10x13-ft raw size by slashing with 50 to 60-ft diamond drill holes. Calculated explosive charges are used to avoid wall and roof shattering. Still more recently jacklegs and sectional steel replaced the diamond drills, resulting in the same work for less than half the cost, see Figs. 1 and 2. Crosscuts at right angles to the main haulage drifts, which cross through the center of the ore-body, divide the ore into 200-ft blocks. Eight slusher drifts on 50-ft centers draw from one block. The slusher floor is 11 ft above the rail, inclined at 1 pct grade, and the top is 18 ft below the undercut. The finished slusher drift is 102.5 or 120 ft long, depending on whether it is north or south of the crosscut. Drawpoints are staggered on each side at 17.5-ft centers. The completed drift is concreted and has an inclined ramp and a vent at the back. When crosscuts and gangways have been excavated and concreted and slusher stations installed, slusher drift development is carried out in 10 clear-cut stages: 1—Pilot drift is driven full length, 5x7 ft. 2—Station is excavated at half-way point in pilot drift. 3—Pilot drift is enlarged to slusher drift size by drilling. 4—Lower part of slash is blasted and mucked for floor concrete. 5—Floor is poured. 6—Inside upper half of slusher drift is blasted, mucked, and concreted. 7—Outside upper half of slusher drift is blasted, mucked, and concreted. 8—Drawpoints are excavated. 9—Drawpoints are concreted. 10—Concrete ramp and sheave protection recess are constructed at back end of slusher drift. A 5x7-ft pilot drift is driven full length on the center line of the proposed slusher drift using a jackleg and detachable bits on 7/8-in. hexagon steel. A 10-hp air-driven slusher and 36-in. scraper pull muck directly into cars in the main haulage crosscut, see Fig. 2. Operations are on a three-shift basis. One man mucks the previous round, drills, and blasts his round in a shift. Average advance is 5 ft per shift. When the pilot drift is completed, 7 ft of drift in the center section is enlarged to full raw slusher drift size of 10x13 ft, for the set-up to drill long slash holes. The pilot drift is slashed to full raw size from this station with jacklegs and tungsten carbide chisel bits on 7/8-in. sectional steel. Crews line the holes without trouble, working from controls established by the engineers, and the pattern of holes for the slash is arranged to give the least shattering effect

Jan 1, 1955

By William H. Spice

Exploratory drilling in South Central Texas for the year 1944 showed a marked increase over that of 1943 and resulted in a similar increase in new fields discovered. In this area, which comprises the 30 counties included in district No. I, Oil and Gas Division, Railroad Commission of Texas,? 61 exploratory wells were drilled during 1944 as compared with 29 exploratory wells drilled during 1943, or an increase of over 100 per cent. Three new oil fields, two new gas fields and one gas-distillate field were discovered during the year, as compared with one new oil field and one new gas field discovered during 1943. These new fields were the result of exploratory drilling throughout the district along the Wilcox trend and the deeper Edwards lime trend, which was started during the previous year. The Wilcox trend yielded the new Loma iilta-Wilcox oil field and the San Caja gas-* tlistillate field, both in McMullen County. The Charlotte field, in Atascosa County, was discovered along the deeper Edwards lime trend. These three discoveries were of considerable importance and subsequent development should indicate the desirability of continued exploration along these trends. The other three discoveries, United oil field in Guadalupe County, Pederson gas field in Milam County and Van Cleve gas field in Zavalla County, were of minor importance. Charlotte Field, Atascosa County, was discovered by the Humble Oil and Refining Company&apos;s No. 3 Pruitt, completcd on Aug. 9, 1944, flowing 176 bbl. per day, 3/16-in. choke, 710 lb. tubing, 475 lb. casing pressures, 37.7º A.P.I. gravity, from the top of the Edwards lime from 6917 to 6923 ft. Two oil wells were completed during the year in this field. This discovery is 14 miles southwest of the same company&apos;s Imogene field, also producing from the Edwards lime but with considerable difference in reservoir characteristics. The discovery of this field is the result of surface geology and subsequent seismograph survey of the area. Loma Alta-Wilcox Field, McMullen County, was discovered by the Atlantic Refining Company&apos;s No. I Atkinson, completed on June I, 1944, flowing 102 bbl. per day, 9/64-in. choke, 1900 lb. tubing pressure, 37º A.P.I. gravity, from Wilcox sand from 6866 to 6869 ft. after being drilled to a total depth of 7185 ft. This discovery is the result of subsurface geology and an extensive seismograph survey of the entire area. Sun Caja Field, McMullen County, was discovered by Edwin M. Jones No. 2-C Ezzell, completed on June 2, 1944 as a dual completion in the Wilcox sands, flowing 1,740,000 cu. ft. gas with 53 bbl. distillate, 1/4-in. choke, 2035 lb. tubing pressure, 53.2º A.P.I. gravity, from sand 6416 to 6453 ft. and flowing 2,000,000 cu. ft. of gas with 127 bbl. distillate, 1/4-in. choke, 2500 lb. tubing pressure, 50º A.P.I. gravity, from sand 6889 to 6916 ft., after being drilled to a total depth of 7264 ft. Three gas-distillate wells were completed during

Jan 1, 1945

Abbey, Robert Graham, District Mgr. The W W. Sly Mfg. Co,. 50 Church St, New York, N. Y. &apos;21 Abbott, A. N., Mines Supt., Mazapil Copper Co., Ltd ..Concepcion del Oro, Zac., Mexico. &apos;23 Abbott, Argyle Campbell, Dev. Dept, E I du Pont de Nemours & Co, Wilmington, Del. &apos;29 Abbott, Clarence E., V.P, Charge of Raw Materials, Tenn. Coal, Iron & R. R. Co, 1242 Brown-Marx Bldg, Birmingham, Ala. &apos;04 Abbott, Louis Benjamin, Chief Engr., Elkhorn Div., Consolidation Coal Co, Jenkins, Ky. &apos;15 Abeel, George H., Jr., Cons. Min. Engr Box 427, Santa Monica, Cal. &apos;18 Abel, Albert E., Asst. to Pres, Valley Mould & Iron Corp Hubbard, Ohio. &apos;19 Abel, Raymond L., Asst. Prof., Dept. of Pet Refin., Univ. of Pittsburgh Pittsburgh, Pa. &apos;28 Abell, Leo M., Research Engr, Sullivan Concentrator Chapman Camp, B. C., Canada. &apos;31 Abernathy, George Elmer, Prof. of Geol. & Min . Kansas State Teachers College, Pittsburg, Kans. &apos;20 Aborn, Robert H., Research Lab, U. S. Steel Corp. Lincoln Highway, Kearny, N. J. &apos;19 Abozeid, Mahmood, Dept. of Mines & Quarries Cairo, Egypt. &apos;26 Abraham, Arthur W. Box 1466, Bakersfield, Cal. &apos;20

Jan 1, 1923

By William C. Harrigan, William D. Nix

Dynamic measurements of Young&apos;s modulus have been made for poly crystalline Ni-W alloys from room temperature to 800°C. The alloys studied range in composition from pure nickel to Ni-10 at. pct W. The results indicate that Young&apos;s modulus decreases linearly with temperature above the Curie temperature. The rate of change of Young&apos;s Modulus with temperature mas found to range from 104 psi per "C for pure nickel to 0.82 x 104 psi per °C for Mi-10 pct W. At all temperatures the elastic modulus decreases with increcrsing tungsten content up to 1 at. pct W, and increases as the tungsten content is increased above that level. Young&apos;s modulus decreases slightly as the carbon content is increased from 0.002 to 0.09 wt pct C THE knowledge of the elastic modulus of metals and alloys is important for a number of reasons. The first and most obvious reason comes from the need to predict elastic deflections under given loading conditions. A second and somewhat more subtle reason comes from the fact that the elastic properties of an alloy must be known before a proper account of the mechanisms of plastic deformation can be made. This is especially true for high-temperature creep of crystalline solids. Sherby and his coworkers have shown that the high-temperature steady-state creep rates of crystalline solids are inversely related to the elastic modulus1,2 and that the temperature dependence of the elastic modulus must be taken into account if reliable determinations of the activation energy for creep are to be made. In addition, measurements of the elastic constants of solid solutions are needed to allow one to assess the modulus interaction contribution to solid-solution Strengthening.3-5 Pelloux and Grant6 have demonstrated that substantial solid-solution strengthening at room temperature and elevated temperatures occurs when refractory metal solute atoms are added to nickel. While the high-temperature elastic properties of pure nickel have been measured by a number of authors,7-10 the elastic properties of nickel-based refractory metal alloys have not been determined. The purpose of this paper is to report on measurements of Young&apos;s modulus of polycrystalline Ni-W alloys at elevated temperatures. It is expected that these measurements will be valuable to studies of the mechanical properties of nickel-based refractory metal solid solutions. I) EXPERIMENTAL Young&apos;s moduli of polycrystalline samples were determined by a dynamic method in order to reduce high- temperature anelastic and plastic relaxations. The samples were forced in transverse free-free vibration; that is, both ends of the sample were unrestrained and the vibration was transverse to the long axis. The fundamental resonant frequency was determined by the Forster method.11 The analysis of this type of vibration which was formulated by Rayleigh,12 Timo-chenko,13 and pickett,14 and reviewed by Fine," leads where fn is the resonant frequency of the nth mode, r is the radius of the circular cross section. L is the specimen length, ßn is 1.5056 for free-free vibration in the fundamental mode of vibration, 6 is the mass density, and E is Young&apos;s modulus in the axial direction. This equation can be transformed into: E = 9.17605 x 10-6(L/D)E/Lf2 [2] where E is Young&apos;s modulus in psi, L is the length in inches, d is the diameter in inches, W is the weight in grams, and f is the resonance frequency in cps. Eq. [2] was further modified in order to take account of the thermal expansion of the samples. The resulting correct term is: where the thermal expansion coefficients for nickel and tungsten, respectively. Xw is the atom fraction of tungsten in the sample and T is the temperature in "C. The treatment of the thermal expansion coefficient as a linear function of composition seems sufficiently accurate since an error of 25 pct in the expansion coefficient will result in only a 0.3 pct error in the modulus at 1000°C. A) Apparatus. The equipment for this investigation has been described by Lytton et al.16 Several modifications of the equipment have been made. The most significant change involved replacing the detector crystal transducer with a magnetic transducer. A phonographic magnetic transducer was employed as a sensing device since the contact pressure necessary to produce a stable signal is much less than that for a crystal transducer. This magnetic transducer is also not affected by conditions of high temperature and vacuum which are present in these experiments. The vacuum was 10-5 torr at room temperature and about 5 x 10-4 torr at 900°C. This was sufficient to prevent surface contamination of the samples during the tests. The samples were heated in an elliptical furnace with a quartz lamp at one focal line and the sample at the other, as described by Lytton et a1.16 The temperature of the sample was measured by monitoring the

Jan 1, 1969

By S. J. Matas, R. F. Hehemann, R. H. Goodenow

The hot-stage metallographic method has been employed to determine radial growth rates of upper and lower bainite. Lower bainite appears to grow as individual plates that increase in both length and thickness while upper bainite grows as sheaves of closely spaced plates or needles. A discontinuity in the temperature dependence of the growth rate appears to be associated with the transition from upper to lower bainite and stepped quenching experiments suggest that lower bainite will not continue to grow when the temperature is raised to the upper range. Thus, a single process does not appear to control the growth of both upper and lower bainite. A tentative model based on the forces acting on a dislocation interface is proposed to account for the slow growth of bainite. It has been recognized since the early studies of Davenport and Bain that a close relationship exists between the martensite and bainite transformations in steels. However, diffusion of carbon during the transformation has lead to considerable controversy concerning the reaction mechanism.1-7 Many studies4,5,7-9 have emphasized the structura and kinetic aspects of the bainite reaction and, in particular, the difference observed between the two forms of bainite—frequently termed upper and lower bainite. A kinetic difference between the two types of bainite has been revealed in the activation energy determined from the overall reaction;4,5 however, many difficulties arise in an interpretation of these activation energies since a number of temperature dependent factors contribute to the kinetics of the overall reaction. The displacive surface relief10 accompanying the bainite reaction permits a separation of the nuclea-tion and growth contributions to the reaction and allows the kinetics of the growth process to be examined. Several investigations of this type have been conducted; however, they have been restricted to the low temperature range.3&apos;6&apos;11 Here, bainite plates are observed to grow slowly in both length and width. The present investigation extends such studies to include the upper bainite range. MATERIALS AND PROCEDURE Materials. The composition of the steels studied in this investigation are presented in Table I. The range of composition permitted a study of the effect of carbon content on the growth rate of upper bainite in the 9 pct Ni steels and consideration of both upper and lower bainite in the higher carbon steels. These steels were received as hot-rolled rounds and were forged to approximately 1/2 in. thick plates for preparation of metallographic specimens. In order to produce an essentially zero carbon steel, Steel A was decarburized in wet hydrogen at 1550°F for 15 days with the result tabulated as Steel AD. Experimental Procedure. In order to study the slow growth of the displacive transformation product, a commercially available Leitz hot stage was modified to permit heating of the specimen by its own resistance in a manner similar to that employed by other investigators.6 The furnace chamber was maintained at a pressure of 2 to 3 X 10-5 mm Hg prior to austenitizing at 2000° ± 12° F for 5 min. Samples could be cooled from the austenitizing to the transformation temperature in approximately 15 sec and the progress of transformation was recorded with a 9 cm by 12 cm single frame camera or a 16 mm movie camera. RESULTS AND DISCUSSION Growth Characteristics. The general growth characteristics observed in this investigation were analogous to those reported previously.3,6,11 Typical growth sequences for the high temperature and low temperature forms are illustrated in Figs. 1 to 5. In both temperature ranges, bainite plates increase in length at slow, temperature dependent rates until interrupted by a grain boundary, another plate, or

Jan 1, 1963

By R. Laird Auchmuty

FOREWORD THE A. I. M. E. Subcommittee on Bituminous Mining has been trying for several years to secure the information that was collected by the Marquette Cement Manufacturing Co. on the subsidence of its property caused by mining coal beneath it. The Marquette company was willing to have these data used, but it was impossible to obtain them because the records had been filed away. About two years ago these records became available and the engineering data presented herewith were compiled from them by R. L. Auchmuty, assisted by L. E. Young, who was connected with the collection of the information. On account of the cost, it is impossible to reproduce all of the data here, although the original information is on file with the records of the Committee on Ground Movement and Subsidence. The accompanying charts show representative and average data and give only the engineering information with enough description to tell how it was obtained. It is hoped that all of those connected with the original case will participate in the discussion that this will bring forth. HOWARD N. EAVENSON, Chairman, Subcommittee on Bituminous Coal Mining.

Jan 1, 1931

By Finn Ouchterlony

A simple bilinear R-curve description of crack extension resistance is applied to the testing of sub-size rock core specimens. The K-curve consists of a linear sub-critical part and a flat post-critical part. Formulas for the apparent energy rate resistance quantities Gm, Jm, and [R] are developed. Experiments on notched cores of Ekeberg marble, Bohus granite, and Stripa granite are compared with these predictions. The R-curve model gives reasonable results for Gm -data but fails essentially to describe the Jm and [R]-data. Another model with a sharply increasing linear post-critical part could possibly account for the [R]-data, but direct R-curve measurements seem a better approach.

Jan 1, 1982

By N. S. Stoloff, K. R. Jordan

The temperatwe and grain size dependence of the mechanical avoperties of ordered and disordered Fe-49 pct Co-2 Pct V were investigated. The yield and flow stresses obeyed the Hall-Petch relationship u = ai + kd-&apos;I2. Ohdering reduced the intercept stress cjj and raised the Petch slope, k, at all temperatures. Ordering also increased the temperatwe dependence of k. The ductile to brittle transition temperature increased with order and grair~ size. Cleavage fracture was nucleation limited and the fracture stress did not zlary linearly with d-&apos;". A quantitative test of the Cottrell-Petch fracture theory (and recent modifications which consider the influence of slip mode), demonstvated that this theory is not applicable to FeCo-V. COTTRELL&apos; and etch&apos; independently suggested that a criterion for cleavage failure at the yield point, a,, based on dislocation pileups at a grain boundary or other obstacle to dislocat.ion motion, is: aYYkd&apos;I2 1 opy [ll or, equivalently, aikz,d112 +k:)bpy [2] where a, and ky are the Hall-Petch intercept and slope, respectively, 2d is the grain diameter, P is a geometric factor dependent on the macroscopic ratio between shear and tensile stress, p is the shear modulus, and y is the true elastic surface energy. When the product of quantities on the left side of the equation is equal to or exceeds that on the right, cracks should be able to nucleate and propagate at the yield stress, as shown schematically in Fig. 1. Therefore a high intercept stress, high Petch slope, or coarse grain size favors brittleness. petch3 associated the existence of a ductile to brittle transition in ferrous alloys with the temperature dependence of ai. One of the earliest modifications of the Cottrell-Petch theory was presented by ~rmstrong,~ who derived an expression for transition temperature in terms of several measurable flow and fracture parameters. The latter paper was able to rationalize situations in which the transition temperature increases with decl-easing grain size, as in the case of molybdenum,&apos; and also suggested that Ppy should be a function of grain size as well as temperature. More recently Johnston et a1.6 and Smith and worthington7 have suggested that the temperature or composition dependence ol&apos; ky must also be taken into account if there is any cha.nge in deformation mode, as from wavy to planar slip, or wavy slip to twinning, with change in temperature or solute content. Armstrong %as suggested that for hcp metals changes in o;k,dw> o;k,d1/2< / is / ^^^^ / / y_______________________________________ d-"2 Fig. l—Schematic representation of grain size dependence of yield stress, cry, and fracture stress, CTF. Intersection defined by Cottrell-Petch equation. slip mode should be incorporated in the theory through changes in the critical resolved shear stress for the slip system which controls ky. The purpose of the present investigation was to critically test the modified677 Cottrell-Petch theory of fracture in the superlattice alloy Fe-49 pct Co-2 pct V, by studying the grain size dependence of the yield and fracture stresses over a range of temperatures, in conjunction with an investigation of slip mode and fracture behavior. Previous work has shown that long range order results in a sharp decrease in flow stress, a small increase in work hardening rate and a drastic upward shift in the ductile-brittle transition temperature of F~CO-V.~&apos;~ The only comprehensive study of slip character in this alloy has been reported in a preliminary account of the present investigation.10 EXPERIMENTAL PROCEDURE The experimental work was carried out on material produced from a 10 lb vacuum melted ingot, of composition 49.32 wt pct Co, 2.09 wt pct V, balance Fe. 30-mil thick sheet samples with a 1; in. gage section were machined from cold rolled stock. The degree of cold work ranged from 85 pct for the finest grained samples to 5 pct for the coarsest grain size. Details of ingot fabrication are reported elsewhere." Equi-axed grain sizes in the range 12.7 to 75.4 p were obtained by annealing for varying times at 850°C. (Re-crystallization annealing time, rather than temperature , was varied to control grain size to insure that samples of all grain sizes contained equivalent quenched-in vacancy and interstitial concentrations.) Grain sizes were measured by the line intercept method on several specimens of each grain size. Following recrystallization, all samples were disordered by quenching into iced brine.

Jan 1, 1970

By W. T. Bell, M. P. Lebourg

The perforating of multiple tubingless completions, in which two or more strings of 27/8-in. OD casing are installed in the same borehole, presents two basic problems. First, good completion practices require an eficient perforator that leaves no debris to interfere with subsequent completion operations. Second, and of more complicated nature, a system is needed for controlling the direction of fire so that adjacent strings are not damaged. Development of of a 2-in. OD, steel retrievable, shnped-charge gun has solved the first problem. The second was resolved through development of three different devices to provide directional perforating for the two types of completion methods being employed today. These include a mechanical orienting device and two self-orienting radiation devices. Conceivably, the latter methods could be adapted to the directional perforating (of .upper zones) of conventional dual and triple completions without removing production tubing and packers. INTRODUCTION The recent trend to multiple tubingless completions,&apos; wherein two or more strings of 27/8-in. OD casing are installed in the same borehole, has presented two basic perforating problems. The first problem to be overcome was the design of a gun that would result in efficient perforations without causing debris to bridge in these small-diameter casings. The second problem was, of course, to devise a system for controlling the direction of fire such that adjacent strings would not be damaged. The problem of gun debris in slim-casing completions has been well defined in the numerous 27/8-in. single tubingless completions which have been effected during recent years with the expendable-type perforators. Failure of expendable-gun debris to settle out properly, even with good gun break-up, has resulted in bridging inside these small-diameter casings. This, in turn, has interfered with completion and re-conditioning operations. The past two years have clearly shown, in fact, that debris problems are not confined to this small range of casing with most designs of expendable-type guns. A high incidence of bridging has even been reported in 4%-in. OD casing. The perforating of multiple tubingless completions has entailed, therefore, the development of a completely debris-free gun of adequate performance, as well as the necessary devices to provide positive directional perforating in the two completion methods presently being employed. THE GUN —DESIGN CONSIDERATIONS The design of a shaped-charge gun for slim-casing perforating has presented a maze of interrelated prob-lems. Since the primary specification has been leveled at efficient charge performance with complete elimination of gun debris, it has been necessary to develop a retrievable steel-carrier gun of tubular construction to house the charges. The carrier must be retrievable through 2.29-in. API pump-seating nipples which are usually installed in 2 7/8-in. strings. To provide for recovery of the gun from the well, swelling of the carrier on firing must be carefully controlled. Control of swelling automatically means control of explosive weight in the shaped charge which, in turn, influences charge performance. Carrier swelling also depends upon the confinement pressure at the level being perforated, which imposes a hydrostatic pressure-depth limitation. Burr interference on the wall of the carrier, resulting from passage of the jet through the carrier wall, must be eliminated by suitable design. Clearly then, a satisfactory shaped-charge gun design for slim-casing operations represents a fine balance between carrier swelling, hydrostatic pressure, explosive weight and charge performance. Additionally, to lend itself to directional perforating, the gun design must provide a positive locking mechanism for individual charges within the gun carrier. This fixes charge orientation within the carrier and prevents

By T. Turner, C. L. Zimmerman, U. Kappus

The purpose of the project is to divert flood flows of North Potato Creek. The project is located in the southeast corner of Tennessee near Copperhill, approximately 160 km north of Atlanta, GA. The project consists of: a 28-m high dam, a 0.9-m diam outlet conduit, an emergency spillway, and a 4.0-m diam hard rock transbasin diversion tunnel. This flood-water management system was part of Cities Service Co. mine safety program for the Cherokee ore body, which is partially located within the creek channel. The following paper describes the entire project development from feasibility studies to design and construction management.

Jan 1, 1981