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By T. M. Berry

In the past few years changes have taken place in shaft sinking. Progress has been made with types of machinery designed, developed, and made available to shaft sinking contractors. This is particularly true of drilling and mucking equipment. Compared with conventional clamshell loading, mucking or loading with a crawler-mounted overshot loader is a new technique for shaft work. There are several methods of clamshell loading. Dravo Construction Co. mounts an air tugger on the clamshell to operate the closing line. The load, or holding line, is attached to the hoist of a crane or whirler at the shaft collar. The clamshell is raised or lowered by the hoist when a signal is given by a bell or light system operated by men at the bottom of the shaft. Two men control the drift of the clamshell with tag lines, pulling it to any position in the shaft for loading, or over the shaft muck bucket for emptying. One man operates the air tugger to open and close the clamshell by means of two lines attached to the operating air valve, just as reins are used to drive a horse. One man operates the signal telling the hoist operator when to raise or lower the clamshell. This method requires two hoisting lines in the shaft-the line from the mine hoist that lifts

Dec 1, 1956

Page Foreword. By Edmund M. Wise..................... 3 A.I.M.E. Officers and Dircctors...................... 4 Institute of Metals Division Officers and Committees............ 7 Institute of Metals Division Annual Award Certificate............ 8 Institute of Metals Division Lectures and Lecturers............. 9 Photograph of E. H. Dix, Jr., Institute of Metals Division Lecturer...... 10 PAPERS Acceleration of the Rate of Corrosion by High Constant Stresses. By E. H. Dm, JR. (Institute of Metals Division Lecture, T. P. 1204).......... 11 Variation of Internal Friction with Grain Size. By Clarence Zener and R. H. Randall. (T.P. 1146, with discussion) .............41 Changes in Damping Capacity during Annealing of Alpha Brass. By John T. NoRton. (T.P. 1168, with discussion)................49 An Electron Diffraction Study of Anodic Films. By R. A. HarrinQton and H. R. Nelson. (T.P. 1158).....................62 Determination of Orientations by Etch Pits. By Charles S. Barrett .and L. H. Levenson. (T.P. 1171, with discussion).............76 Process of Precipitation from Solid Solution, I—A Crystallographic Mechanism for the Aluminum-copper Alloys. By Carl H. Samans. (T.P. 1186). . . 85 Age-hardening of Aluminum Alloys, IV — Discussion of the Theory. By WilTJam L. Fink and Dana W. Smith. (T.P. 1083, with discussion). . . 95 Structure of Aluminum after Compression. By Charles S. BaRREtt and L. H. evensonON. (T.P. 1104, with discussion)................112 Recrystallization Texture of Aluminum after Compression. By ChaRlEs S. BarRett. (T.P. 1141, with discussion)................128 Plastic Deformation and Recrystallization of Aluminum Single Crystals. By J. A. Collins and C. H. Mathewson. (T.P. 1145, with discussion) . . . 150 Recovery and Recrystailization in Long-time Annealing of 70-30 Brass. By S. E. Maddigan and A. I. Blank. . (T.P, 1166, with disonssion).....170 Correlation of Deformation and Recrystallization Textures of Rolled 70-30 Brass. By R. M. Brick. (T.P. 1144, with discussion).........193 Tensile Deformation of Critically Oriented Brass Crystals. By H. L. Burghoff. (T.P. 1149).............................214 Recrystallization of Lead. By Paul A. Beck. (T.P. 1101, with discussion). . 222 Simple Method of Thermal Analysis Permitting Quantitative Measurements of Specific and Latent Heats. By Cyril Stanley Smith. (T.P. 1100, with discussion).............................236 Metallographic Study of Internal Oxidation in the Alpha Solid Solutions of Copper. By Frederick N. Rhines. (T.P. 1162, with discussion). . . . 246

Jan 1, 1940

Page Foreword. By Edmund M. Wise..................... 3 A.I.M.E. Officers and Dircctors...................... 4 Institute of Metals Division Officers and Committees............ 7 Institute of Metals Division Annual Award Certificate............ 8 Institute of Metals Division Lectures and Lecturers............. 9 Photograph of E. H. Dix, Jr., Institute of Metals Division Lecturer...... 10 PAPERS Acceleration of the Rate of Corrosion by High Constant Stresses. By E. H. Dm, JR. (Institute of Metals Division Lecture, T. P. 1204).......... 11 Variation of Internal Friction with Grain Size. By Clarence Zener and R. H. Randall. (T.P. 1146, with discussion) .............41 Changes in Damping Capacity during Annealing of Alpha Brass. By John T. NoRton. (T.P. 1168, with discussion)................49 An Electron Diffraction Study of Anodic Films. By R. A. HarrinQton and H. R. Nelson. (T.P. 1158).....................62 Determination of Orientations by Etch Pits. By Charles S. Barrett .and L. H. Levenson. (T.P. 1171, with discussion).............76 Process of Precipitation from Solid Solution, I—A Crystallographic Mechanism for the Aluminum-copper Alloys. By Carl H. Samans. (T.P. 1186). . . 85 Age-hardening of Aluminum Alloys, IV — Discussion of the Theory. By WilTJam L. Fink and Dana W. Smith. (T.P. 1083, with discussion). . . 95 Structure of Aluminum after Compression. By Charles S. BaRREtt and L. H. evensonON. (T.P. 1104, with discussion)................112 Recrystallization Texture of Aluminum after Compression. By ChaRlEs S. BarRett. (T.P. 1141, with discussion)................128 Plastic Deformation and Recrystallization of Aluminum Single Crystals. By J. A. Collins and C. H. Mathewson. (T.P. 1145, with discussion) . . . 150 Recovery and Recrystailization in Long-time Annealing of 70-30 Brass. By S. E. Maddigan and A. I. Blank. . (T.P, 1166, with disonssion).....170 Correlation of Deformation and Recrystallization Textures of Rolled 70-30 Brass. By R. M. Brick. (T.P. 1144, with discussion).........193 Tensile Deformation of Critically Oriented Brass Crystals. By H. L. Burghoff. (T.P. 1149).............................214 Recrystallization of Lead. By Paul A. Beck. (T.P. 1101, with discussion). . 222 Simple Method of Thermal Analysis Permitting Quantitative Measurements of Specific and Latent Heats. By Cyril Stanley Smith. (T.P. 1100, with discussion).............................236 Metallographic Study of Internal Oxidation in the Alpha Solid Solutions of Copper. By Frederick N. Rhines. (T.P. 1162, with discussion). . . . 246

Jan 1, 1940

AN intermetallic compound, Ni3A1, has an ordered fcc structure of type Ll2, and shows peculiar dependence of the yield stress upon temperature; i.e., the yield stress increases by a factor of six upon raising the temperature from 77" to 900K1, 2 This compound is technologically important, since many nickel-base superalloys owe their high-temperature strength to the peculiar yield stress behavior of Ni3Al. The only study of the elastic behavior of this compound was made by Davies and Stoloff,1 who determined Young's modulus of poly crystalline Ni3A1 between 300" and 730°K. The determination of single-crystal elastic constants of Ni3A1 is therefore of interest in connection with dislocation dynamics and is reported in this paper. A single-crystal specimen, 1 by 1 by 3 cm, was cut from an ingot generously supplied by Dr. B. H. Kear of Pratt & Whitney Aircraft. Following initial machining with a Servomet and a surface grinder, the specimen was etched and annealed at 1100°C for 5 hr in vacuum followed by furnace cooling. Two parallel faces were oriented normal to within ±l deg of a [I101 crystallographic axis by the back-reflection Laue technique. The parallel faces were hand-lapped, etched, and polished by the usual metallographic procedures. Final thickness along the [I101 axis was (0.9325 * 0.0005) cm. Chemical analysis gave an average composition of 87.35 pct Ni. Total impurity content is esimated to be no more than 0.1 pct. The elastic constants were calculated from measurements of ultrasonic waves which were propagated along the [110] axis. A longitudinal wave and two shear waves whose displacements are aligned along the [ 110], [li~], and [001] directions, respectively, are necessary in order to completely specify the three elastic constants. Two 3/6-in. quartz transducers were bonded to the parallel faces of the sample with ~ac-seal.3 Although this bond was sensitive to thermal shock, it performed satisfactorily over the entire temperature range for both longitudinal and shear wave propagation. A frequency of 5 mHz was employed in the method of Williams and Lamb4 in order to measure the absolute value of the ultrasonic velocity. The pulse-overlap technique of Mcskimin5 was also used at this frequency in order to determine the shift in the ultrasonic velocity

Jan 1, 1970

By D. Harrington

EFFICIENT ventilation of metal mines consists in having such complete control of air currents that. there is always supplied at places where men work sufficient moving air to allow working at maximum capacity without injury to health; and in case of underground fire or of surface fire in the vicinity of mine openings, underground air currents may be quickly reversed if desired, or air may be sent into or excluded from any region and fire fumes confined to only part of the mine workings, instead of penetrating practically the entire mine. Health and safety of workers in mines as well as proper safeguarding and operating efficiency of mining properties are so intimately associated with proper ventilation of mines (both coal and metal) that they are inseparable, yet mine ventilation is only too frequently neglected, especially in metal mines. The metalliferous operator, generally not confronted with inflammable gas or explosive dust which so frequently force ventilation of coal mines, usually disregards air supply altogether except such as may be obtained from compressed air; and generally, even when attention is given to metal-mine ventilation, the air currents rarely are found where they are needed, namely, the working places, especially the working faces. After several years' study of miners' consumption, the writer is. convinced that long continued breathing of air impregnated with large quantities of any kind of finely divided dust, such as is found in a large number of the working places of our mines, will ultimately produce some respiratory disease, whether it be asthma, bronchitis, or phthisis; and the progress of these diseases is hastened. if there are also present high temperatures, high humidities, or harmful gases or if there is present (and allowed to remain to be breathed) large quantities of the finely divided dust when air temperatures are low, hence favorable to maximum performance of work with accompanied maximum breathing into the respiratory passages of the harmful material. It is generally accepted

Jan 2, 1922

By D. Harrington

Efficient ventilation of metal mines consists in having such complete control of air currents that there is always supplied at placcs where men work sufficient moving air to allow working at maximum capacity without injury to health; and in case of underground fire or of surface fire in the vicinity of mine openings, underground air currents may be quickly reversed if desired, or air may be sent into or excluded from any region and fire fumes confined to only part of the mine workings, instead of penetrating practically the entire mine. Health and safety of workers in mines as well as proper safeguarding and operating efficiency of mining properties are so intimately associated with proper ventilation of mines (both coal and metal) that they are inseparable, yet ventilation is only too frequently neglected, especial1y in metal mines. The metalliferous operator, generally not confronted with inflammable gas or explosive dust which so frequently force ventilation of coal mines, usually disregards air supply altogether except such as may be obtained from compressed air; and generally, even when attention is given to metal-mine ventilation, the air currents rarely are found where they are needed, namely, the working places, especially the working faces. After several years' study of miners' consumption, the writer is convinced that long continued breathing of air impregnated with large quantities of any kind of finely divided dust, such as is found in a large number of the working places of our mines, will ultimately produce some respiratory disease, whether it be asthma, bronchitis, or phthisis; and the progress of these diseases is hastened if there are also present high temperatures, high humidities, or harmful gases or if there is present (and allowed to remain to be breathed) large quantities of the finely divided dust when air temperatures are low, hence favorable to maximum performance of work with accompanied maximum breathing into the respiratory passages of the harmful material. It is generally accepted

Jan 1, 1923

By D. Harrington

Efficient ventilation of metal mines consists in having such complete control of air currents that there is always supplied at placcs where men work sufficient moving air to allow working at maximum capacity without injury to health; and in case of underground fire or of surface fire in the vicinity of mine openings, underground air currents may be quickly reversed if desired, or air may be sent into or excluded from any region and fire fumes confined to only part of the mine workings, instead of penetrating practically the entire mine. Health and safety of workers in mines as well as proper safeguarding and operating efficiency of mining properties are so intimately associated with proper ventilation of mines (both coal and metal) that they are inseparable, yet ventilation is only too frequently neglected, especial1y in metal mines. The metalliferous operator, generally not confronted with inflammable gas or explosive dust which so frequently force ventilation of coal mines, usually disregards air supply altogether except such as may be obtained from compressed air; and generally, even when attention is given to metal-mine ventilation, the air currents rarely are found where they are needed, namely, the working places, especially the working faces. After several years' study of miners' consumption, the writer is convinced that long continued breathing of air impregnated with large quantities of any kind of finely divided dust, such as is found in a large number of the working places of our mines, will ultimately produce some respiratory disease, whether it be asthma, bronchitis, or phthisis; and the progress of these diseases is hastened if there are also present high temperatures, high humidities, or harmful gases or if there is present (and allowed to remain to be breathed) large quantities of the finely divided dust when air temperatures are low, hence favorable to maximum performance of work with accompanied maximum breathing into the respiratory passages of the harmful material. It is generally accepted

Jan 1, 1923

By H. C. Rogers, B. W. Roberts

Vanadium foils and wires, either cold-worked or recrystallized, show a ductile-brittle-ductile fracture sequence with temperature. At about 150°C the hydrogenated vanadium wires are found to be ductile. At room temperature the wires show brittle fracture, and at liquid nitrogen temperature the wires are again ductile, although to a lesser extent than found at 150°C. Hydrogenated cold-rolled vanadium foils have been found to fracture in unusually straight lines along the [100] texture directions. The hydrogen content required to show this [loo] texture fracture is limited to a few atomic percent in range. Hydrogen content above this range causes fracture to occur in random directions. PRELIMINARY experiments with hydrogenated vanadium foils indicated that the embrittling effect of the hydrogen on the vanadium, which was severe at room temperature, was reduced at both lower and higher temperatures. In order to investigate more quantitatively the ductility changes with temperature, vanadium wires were tested in tension at three temperatures. The reduction of area was measured and the fractures examined. Specimen Preparation—The material used was kindly supplied by A. U. Seyboltl in the form of M-in. rod. The nominal analysis was: 99.2 pct V assay, 0.2 pct C, 0.01 pct Si, 0.01 pct Fe, 0.015 pct Ca, 0.02 pct O,, 0.01 pct N2, and 0.003 pct H,. The specimens were 0.035-in. diam wires. These were prepared by cold-swaging the supplied rod to the final diameter without intermediate anneal. They were finished with long-bearing dies. The surface was then given a light polishing with 0 emery paper and degreased in trichlorethylene. An X-ray check indicated that the cold-swaged wire had a fairly strong [110] fiber texture. The wires were then recrystallized in vacuum in continuously pumped quartz tubes at two temperatures to give two different grain sizes. One group of wires was given 45 min at 800°C; another, 60 min at 1000°C. The microstructures in Fig. 1 show the wires after they have been electropolished and elec-troetched in 10 pct HCI. After the 800°C anneal, the vanadium grains had a diameter of 1 to 2p and there appeared to be a tendency to elongation in the longitudinal direction. However, the latter may be an etching effect. After the 1000°C anneal, the grains appeared to be equi-axed, but there was a very large spread in grain size, probably due to some impurity segregation in the wire, Fig. 1, right. The grain diameters varied between the limits of 1 to 150p. The small particles shown particularly clearly in Fig. 1, left, are also visible on the polished surface of all samples before etching and are undoubtedly carbides and nitrides of vanadium. An X-ray check indicated these annealed wires had a strong [110} recrystallization fiber texture. The hydrogenation was carried out in an iron retort with dry hydrogen flowing through it, the retort and contents being heated in a tube furnace with a hydrogen atmosphere. The hydrogenation temperature was approximately 500°C. The hydro-genation times chosen were approximately those which would be just enough to cause the vanadium to be brittle at room temperature and thus allow the greatest chance for ductility to occur at the other two temperatures. Part of the fine grained specimens were hydrogenated for 21/2 min at 490°C. Part of the coarse grained specimens were hydro-genated for 11/2 min at 515°C.

Jan 1, 1957

By William M. Shepard

The Tintic mining districts of central Utah com- prise one of the major silver-lead producing areas in the United States. Ore valued at nearly $450 million has been produced from these districts since the initial discoveries, in 1869, of veins cutting the Silver City monzonite stock. Subsequent production from the famous manto-type "ore runs", which characterize the Main Tintic district, was followed during the past 40 years by discovery of the blind orebodies of the East Tintic district, including the famous Tintic Standard mine and the most recent discovery, the Burgin mine, currently being brought to full production by Kennecott Copper. The occurrence of blind orebodies of exceptional size and grade in both the Main and East Tintic districts has made this area a field laboratory of major importance for the study of geochemical dispersion halos and alteration features associated with known ore, and has led to the discovery of additional concealed orebodies. The larger share of the basic data-gathering and interpretation has been done by members of the U.S. Geological Survey who have been studying the Tintic mining areas since before the turn of the century. These studies have been supplemented and expanded by the geological staffs of the local operating mining companies, by exploration geologists and by students.

Jan 4, 1966

By J. S. Blakemore, E. O. Hall

SERRATED yielding, commonly called the Portevin-Le Chatelier effect, is known to occur in a wide range of alloys where the moving dislocations are considered to be locked by the diffusion of solute atoms to them. From the work of Cottrell,1 an approximate relationship between strain rate, E, dislocation density, p , and solute diffusion coefficient, D, giving rise to serrated yielding is: e =Dp

Jan 1, 1969

By Arnulf Muan, W. C. Hahn

Activities of "FeO" in "FeO"-MgO solid solutions have been determined in the temperature interval 1100" to 1300"C by equilibrating oxide samples with pure metallic iron in atmospheres of known oxygen partial pressures. The end members "FeO" and MgO form a complete solid solution series. The system shoztls a considerable positive deviation from Raoult's law. A large amount of data has been accumulated during the past 50 years on stability relations existing among various crystalline and liquid phases in oxide systems of importance in metallurgical processes. By comparison, very little is known about the thermodynamic properties within the various homogeneous phases present in the systems, particularly the crystalline phases. The present paper deals with determination of activities as a function of composition in solid solutions of wüstite ("FeO") and periclase (MgO). Such solid solutions ("Magnesiowustites") have simple sodium chloride structure and are known to be continuous between the end members at elevated temperatures (> 1000°C) and strongly reducing conditions such as prevail in contact with metallic iron. Wiistite has a defect structure in which the ratio of oxygen to iron varies and never has as low a value as 1:1 corresponding to the simplified formula FeO. Within the range of stability of this phase, the composition changes between a maximum oxygen content of approximately 25.6 wt pct (corresponding to the formula FeO.83O) and a minimum oxygen content of approximately 23.2 wt pct (corresponding to the formula Fe0-96O). The activity data to be reported in the present paper are based on using as standard state the wüstite which is in equilibrium with metallic iron at a particular temperature, i.e., "FeO" of minimum oxygen content at each temperature. For sake of simplicity, the formula FeO will be used to represent the wustite phase in the remainder of this paper. Consider the reaction 2 FeO solid solution = 2 Femeta1 + Ozgas in which FeO dissolved in another oxide dissociates to metal and gas. The activity of FeO in the solid solution, relative to "pure FeO" in equilibrium with metallic iron as a standard state, is then expressed as Here Po, and po2 * are the partial pressures of oxygen of the gas phase in equilibrium with metallic iron and the oxide solid solution or "pure FeO", respectively. The equation holds only if the metal phase is essentially pure Fe. The oxide combinations used in the present investigation fulfill this requirement. Magnesia is so much more stable than FeO that for all practical purposes aFe = 1 in the metal phase present in all mixtures used in this investigation. I. EXPERIMENTAL METHOD 1. General Procedure. The experimental method used was analogous to that developed by Foster and Welch1 and used recently by Hahn and Muan.2 It consisted of four steps: a) Determination of the equilibrium between FeO and Fe. b) Determination of d-spacing change with composition in oxide solid solutions (FeO-WO). c) Equilibration of various members of the solid solution series with a metal phase and a gas phase of known oxygen partial pressure. d) Determination of compositions of solid solutions resulting from step (c) by means of data obtained in step (b). 2. Starting Materials. General Aniline and Film Corp. carbonyl iron powder, type HP, was used as the source of metallic iron. A representative analysis was as follows: Fe, 99.6 pct; C, 0.01 to 0.04 pct; 0, 0.1 to 0.3 pct; N, 0.00 to 0.05 pct. Other elements were present as traces only. Wiistite was prepared from "Baker Analyzed" Reagent grade Fe2O3 of reported analysis as follows: Assay (Fe2O3), 98.8 pct; insoluble in HC1, 0.02 pct; not precipitated by NH,OH, 0.02 pct; Zn, 0.003 pct. Production of wüstite was achieved by a two-step

Jan 1, 1962

New Device Eliminates Blasting in Coal A non-explosive device developed by duPont utilizes the high pressure of a gas generated inside a steel tube which is inserted in a hole drilled in a coal seam to break down the face of coal. Chemical reaction is started by an electric current which produces heat to initiate the action. The same heat destroys the starter wire as soon as electric current is no longer needed. The tube containing the chemical is closed at the outer end by a plug with electrical connections, and at the other with a disk that is ruptured by the compressed gases formed. When the gas has been liberated in sufficient quantities to create a desired pressure the disk breaks and the released gas breaks down the coal face. The new device is called a Chemechol.

Jan 10, 1951

By C. R. Hayward

CARLE R. HAYWARD.-I do not want it understood that I think that the conclusion that the time of tempering temperature is immaterial has been definitely proven, but since these are the first definite figures put out, I thought before continuing on more work ourselves, it would be well to present them as progress and for information. J. A. MATHEWS, Syracuse, N. Y.-I think that if Prof. Hayward would consult the paper of Profs. Barus and Strouhal,1 1885, he would find about 250 pages, mostly figures, on this subject, in which they investigated the tempering effect by electrical and magnetic methods. There are so many figures in the paper that it is very difficult reading. One point particularly brought out was that even at a low temperature, such as the boiling point of alcohol, about 60° C., there is a tempering effect, increasing up to 4 hr. One reason they obtained those results, with which the present authors are at variance, was that they started with a high-carbon steel which hardens thoroughly, whereas the steel Prof. Hayward and his collaborator used was a comparatively mild steel which does not take a great deal of hardening. About 3 years ago Mr. Stagg and I published 2 a few figures bearing on the same subject, but we used .a low-carbon alloy steel of high tempering qualities and found a great deal of improvement, particularly in ductility, by continuing the drawing up to 4 hr. We used a chrome-vanadium steel showing after heat treatment 250,000 tensile strength. On short drawing, we got almost no ductility, but by continuing to 4 hr., we raised it to 12 per cent. I believe Prof. Hayward's results are due to using comparatively mild steel, whereas Prof. Barus used drill rod and carried out a, wonderfully exhaustive

Jan 4, 1917

By E. H. Jr. Dix

THE success of the Charpy impact test in the steel industry has led those interested in aluminum alloys to investigate the possible applica¬tion of this test to aluminum and its alloys. In this paper are set forth the results of a few preliminary tests made at the Lynite Laboratories of the Aluminum Manufactures, Inc. In order to study more thor-oughly the significance of the Charpy test, slow-bending tests have been made duplicating the arrangement of the impact machine. Tests have been made on both notched and unnotched specimens of a series of copper-aluminum alloys. APPARATUS The standard American-made Charpy impact machine delivering a blow of over 200 ft.-lb. was- much too large to test aluminum-alloy specimens of the same type used for steel, so that it was necessary either to adopt a larger specimen or to have a special light-weight hammer made. Since there is no known relation between specimens of different sizes, even though geometrically similar, it was decided to adhere to the 10 by 10 mm. specimen. Accordingly, Sauveur and Boylston, the American makers of the machine, were asked to construct a special light-weight pendulum adapted to their standard machine, this pendulum to have one-tenth the capacity of the standard. The writer wishes here to acknowledge his indebtedness to Mr. H. M. Boylston for the personal interest and care exercised in constructing this pendulum. The machine with, the light-weight hammer in place is shown in Fig. 1. It is mounted on a concrete foundation with the concrete covering the flange on the base of the machine. Vibration is further prevented by four 5/8 -in. (15.8 mm.) foundation bolts. The large standard hammer shown against the wall was also used for some of the unnotched bars that requited more than 20 ft.-lb. to rupture.

Jan 4, 1920

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 David Donoghue

Efforts made in the year 1930 and in previous years restricted production in most of the fields of Texas to a point that was satisfactory, at the beginning of 1931, to the majority of producers and buyers. In the Panhandle, North Texas and West Central Texas districts, a few operators with refinery affiliations or contracts either ignored, or by virtue of injunction suits, did not comply with the Railroad Commission's orders, and there was some oil sold at less than posted prices, which, with the Oklahoma City difficulties, caused the first general price reduction. More could have been done perhaps to help the situation on the Gulf Coast and in the Laredo district, but natural advantages are not readily surrendered. East Texas Proration troubles in 1930 were insignificant when compared with those of 1931. In January, 1931, efforts were begun to convince the producers and citizens of East Texas of the necessity of curtailment. Opposition quickly developed and meetings were held in the towns of the region and proration denounced vigorously. Notwithstanding a strenuous campaign for additional legislation waged by many producers, the regular session of the State Legislature refused to strengthen the conservation laws and passed only the Marginal Well Bill, designed to prevent the Commission from prorating small wells. The Railroad Commission held a heated hearing on East Texas in the latter part of March. During April the Commission issued three orders based on the Yates plan for the proration of the East Texas field. Each succeeding order raised the allowable for the field. In June the opposition held more mass meetings at which a plan based on acreage was endorsed. Apparently on the theory that any plan was better than none, the Commission issued an order on July 2 embodying some of the features of the proposed plan, limiting production to 250,000 bbl. per day, and dividing the producing area into 20-acre units participating equally in the outlet. Owing to the bringing in of many wells and the many violators of the Commission's orders, production increased to such an extent that prices went as low as 5c per barrel.

Jan 1, 1932

By Rufus J. Foster

During the discussion on the Preparation and Utilization of Sniall Sizes of Anthracite (page 613 of present volume), several inquiries were made concerning the use of the McClave grate, which was mentioned by Mr. Coxe as having proved satisfactory in the generation of steam at his collieries, and also at a large number of industrial estal)lishments in Scranton and elsewhere. For a more satisfactory repIy to such inquiries than could be furnished in the oral discussion, I have prepared the following paper to be included in the published proceedings. And, as the use of the fuel under consideration necessarily requires the employment of a blower to change the fire, from a condition giving an incandescent radiant heat only to one giving a hot gaseoua flame as well, I shall add a description of the McClave Argand blower and its method of action. The grate and blower combined form a complete and effective system fcr burning small fuels, such as anthracite culm, birdseye, buckwheat, bituminous slack, etc., in boiler and other furnaces; while the grate alone is now extensively used with the larger sizes of hard and soft coal in furnaces where blast is riot required. Fig. 1 is a view of the RlcClave grate as built in two sections. It is constructed on the principle best approved by practice to prevent warping and burning out; that is, it presents no long lines of

Jan 1, 1892

By H. M. Faust

THERE are a number of different types of power plants. Some use coal to generate steam, others use oil or gas either in the form of steam or internal combustion equipment, while still others avail themselves of water power as a source of energy. A general comparison of the relative power production with different sources of energy in the United States, for several different years is set up in Table 1. This table shows that coal was used to generate 85.6 per cent of the total heat power requirements of 1909, and only 59.2 per cent of the 1930 requirements. The increasing proportion of modern heat energy generated by the use of fuel other than coal is apparent. If coal is to maintain its importance as a source of heat energy, the necessity for its improved perform-ance, in which preparation plays an -important part, cannot be stressed too strongly.

Jan 1, 1933

By George Frederick Kunz

The manifold inconveniences resulting from the absence of a uniform standard of mass for determining the weight of precious stones have long been obvious. This lack has been keenly felt in commercial transactions, and those who have devoted time and research to the study of historic diamonds and precious stones have had frequent occasion to deplore the absence of such a standard in the past. In a paper read in Chicago in 1893, before the International Congress of Weights and Measures, held in connection with the World's Columbian Exposition, the writer suggested dividing the carat into 100 parts, and constituting a standard international carat of 200 mg.; that is, 5 diamond carats or 20 pearl grains to a French gram, making 5,000 carats or 20,000 pearl grains to a ki1ogram. He also called attention to the fact that while this would depreciate the present diamoiid carat or pearl grain only about 2.5 per cent., it would abolish the troublesome discrepancies between the various carat-weights now in use, and could be easily explained and understood everywhere.' The subject of the various diamond carats, their incongruity, and the resulting confusion as to the correct weights of historic gems when definite records of them are searched for, has been fully treated by me in an extensive study of this subject in The Book of the Pearl2 To the earnest and unremitting efforts of C. E. Guillaume, Director of the Bureau Internationale des Poids et Mesures at Sévres, is largely due the eventual success of this eminently desirable reform, which he has constantly urged both by articles on the subject and by addresses delivered in Paris before the International Committee for Weights and Measures.3 The general adoption of a uniform standard for dealings in pre-

Jan 1, 1914

By C. S. Allen

WITH increased coal production and mechanization of coal mines many transportation problems arise. The main objective is to bring the coal to the tipple or dump it as quickly as possible. Larger and faster haulage locomotives or two locomotives connected in tandem have been adopted to solve the problem. Motor equipment, gears and control systems of locomotives to be placed on these hauls are carefully studied to meet these requirements, by an analysis of motor characteristic curves with the corresponding tractive effort curves, in order to determine the correct load for maximum efficiency and to determine the approximate schedule. Control equipment is usually considered to be the controller and resistance. Sometimes accelerating curves are calculated in order to obtain smooth starting in the least possible time without slipping the wheels. Train control is very important, but why limit this to acceleration? Deceleration or retardation of the locomotive is a part of the train control and should be given as much consideration as the control for acceleration. TYPES OF BRAKING Common braking systems for mine locomotives utilize screw-type mechanical brakes, dynamic braking and the air brake. For gathering and haulage locomotives, the screw-type mechanical brake is regarded as standard. A brake of this kind cannot be applied without much effort and lapse of time. Motormen, like other people, follow the path of least resistance, and therefore have their brakes ready for instant application-which means that the shoes are virtually dragging. Even then, a motorman bucks and plugs the motors to gain time and avoid as much physical effort as possible. "Bucking of motors" consists in turning the reverse cylinder of the controller to parallel position corresponding to the opposite direction of travel while the locomotive is in motion, without applying power from an external source. When this occurs, both motors tend to act as series generators, because the armatures are revolving and there is residual magnetism in the field circuit. Owing to slight differences in motor manufacture, one of these will generate a slightly higher potential and will overcome the generated voltage of the second and tend to drive it as a motor in the reverse direction. This action retards the locomotive but is very severe on the segments of the reverse cylinder and on the motor commutators. "Plugging motors" is the application of power to the motors corresponding to the opposite direction of travel. In order to "plug" the motors it is necessary first to "buck" them (which reverses the connections to the motors) and then to apply

Jan 1, 1941