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By Donald Ofte

LIQUIDUS temperatures of molten alloys were measured in an oscillating-cup viscosimeter by observing the abrupt increase in the alloy viscosity when the apparatus was cooled below the alloy liquidus temperature. The liquidus transformation can be an elusive thermal effect in an alloy system where a small amount of material is involved in a low-enthalpy liquidus reaction, or where other unfavorable physical conditions interfere. Using the viscosity technique, liquidus temperatures were measured in binary alloys of plutonium with cerium, gallium, and iron, as well as ternary Pu-Ce-Co alloys. The previously described oscillating-cup viscosimeter1 is a torsion pendulum consisting of a right circular, cylindrical tantalum cup fitted to a rigid shaft which, in turn, is suspended by a torsion fiber in a highvacuum system. When the torsion pendulum is placed in oscillation the viscosity of the liquid contained in the cup is a function of both the decay of the oscillation caused by the viscous drag of the liquid contained in the sealed tantalum cup, and the period of the oscillation. The period is measured by a photo-electrically operated timer to the nearest thousandth of a second. Prior to each measurement, the apparatus is held at temperature between 5 and 18 hr to assure thermal equilibrium throughout the 8 to 10-cc alloy sample. When the cup, filled with a liquid metal, is oscillating. only a very thin outer layer of the fluid is in motion. This moving annulus represents the liquid's contribution to the moment of inertia of the torsion pendulum. When the viscosity increases, more liquid is placed in motion, and the slight increase in the moment of inertia causes a corresponding increase in the period of oscillation.

Jan 1, 1967

By John Van N. Dorr

Introduction.................... 212 The DoRR Classifier.........212 History................ 212 Description................... 215 Regulation of Products............. 216 Cost of Operation.............216 Power...........216 Capacity..............216 Uses.................217 The Dorr Thickener.............219 History...........292 Description.............. 221 Speed............ 222 Power......,....223 Repairs.............,... 223 Labor................. 224 Capacity................ 224 Density of Underflow............... 224 Uses.........,.......226 Continuous Counter-Current Decantation....... 227 Concentration..............227 Industrial Uses................228 Acid-Proof Thickeners.......... 228 The Dorr Tray Thickener........... 229 Description.................. 229 Capacity................. 231 The Dorr Agitator................. 232 History................... 232 Description................... 233 Speed.................... 234 Power.................... 234 Renewals................... 235 Efficiency................... 236 Selective Agitation................ 236 Conclusion................... 237

Jan 1, 1915

By P. M. Budge, William L. Fink, Kent R. Van Horn

The investigation of the phase relations of high-purity aluminum-base alloys is a part of the fundamental research program of the laboratories of the Aluminum Company of America. The results of a number of binary and ternary systems have previously been published in the Transactions of this society. The aluminum end of the binary aluminum-titanium system has been studied. This system has received relatively little attention. To the authors' knowledge, there are two previous papers on this subject. E. van Erckelensl determined the constitutional diagram reproduced in Fig. 1. According to this diagram, the liquidus represents the separation of TiA14, (Ti = 30.7 per cent.). He concluded that this is the composition of the compound, because in his work the eutectic horizontal terminated at 30.7 per cent. titanium and the metallographic examinalion of a sample of this composition revealed only one phase. According to the constitutional diagram developed by W. Manchot and A. Leber,² reproduced in Fig. 2 from data given in their article, the liquidus represents the separation of the compound TiA13 (Ti = 37.2 per cent. ). The composition of the compound was derived in a manner similar to that utilized by van Erckelens. Moreover, Manchot and Leber confirmed the composition of the compound by analysis of the constituent left as a residue after dissolving the alloys in weak sodium hydroxide solution. Although these are the only publications describing the constitution of the system, other investigators have studied the composition of the titanium compound. L. WÖhler3 says that there is a compound TiA13 which was later confirmed by W. Manchot and P. Richter4 and by

Jan 1, 1931

By John C. Cook

Long-wave short-pulse radar has been shown capable of exploring to distances of several hundred feet through massive, dry rock salt. Exploration distances of 30 to 60 ft through bituminous coal and massive limestone, respectively, have also been demonstrated with low-power experimental radar equipment in underground mines. Working ranges up to 250 ft in limestone and coal are considered feasible. Radar reflections should be produced by all large electrically contrasting objects such as fault gouge masses, wet shattered ground, metallic mineralization, adjacent mine workings (dry or flooded), and abandoned drill holes. It is believed that radar can locate such obstacles in advance of underground mining through all massive rocks of low free-water content, including many igneous and metamorphic rocks. Three years of studies and experiments in radar exploration through rocks are reported.

Jan 1, 1974

By J. B. Austin, R. H. H. Pierce

IN developing a consistent picture of the thermal expansion of the commercial chromium steels, which cover a range of, carbon contents, it is desirable to know the expansion in the limiting case of the binary, carbon-free, iron-chromium alloys. We have, therefore, determined the thermal expansion of a series of five special alloys, ranging in chromium content from 3 to 10.5 per cent, with not more than 0.03 per cent carbon, over a temperature range extending beyond the transformation region; this low carbon content enables us to draw reasonably reliable conclusions as to the behavior of the carbon-free system. Moreover, the measurements serve to determine the beginning and the end of the alpha-gamma transformation; and they emphasize once more the fact that a transformation temperature determined by any method in which the specimen is .cooled at an appreciable rate is apt to be seriously in error, particularly if the metal contains a transformation-retarding element such as chromium or managanese. The lag, or undercooling, observed at the ?-a transformation is explained in terms of the influence of temperature on transformation velocity; the rather unusual shape of the ? loop is attributed to a change with temperature and with composition of the distribution of chromium between the alpha-iron and gamma-iron solid solutions. The exact composition of the alloys which were obtained through the courtesy of Dr. W. Rohn, of the Heraeus Vakuumschmelze A-G., is given in Table 1. Determinations of the linear thermal expansion and of transformation temperature were carried out in the vacuum dilatometer previously described,1 using a rate of heating and of cooling of 3.0° to 3.5° per minute unless otherwise stated. Magnetic susceptibility, which was measured in studying the rate of transformation, was determined with a magnetic balance, which also has. been described.2

Jan 1, 1935

By C Gunther

Secondary minerals are the result of a process of concentration and enrichment and are commonly richer than the primary minerals of the same deposit. Secondary ores that contain abundant sulphides are commonly dibtinguishable in the field from primary ores; this distinction is more difficult with ores that carry a small quantity only of sulphide minerals, and microscopical examination of the ore in thin section is advisable in all doubtful cases. It is frequently difficult, and in some cases impossible, to determine the primary or secondary character of quartzose gold ores. The safest guide is the presence or absence of gaseous or fluid inclusions in association with the ore minerals; such primary association coupled with a lack of traces of oxidation is indicative of primary origin. Any ore that carries traces of oxidation, such as iron stains, dendritic oxides of manganese, kaolin and so forth must be considered to have been acted upon by surface agencies, and secondary enrichment must be suspected. Further examination, however, may indicate that the contained value is primary, and, therefore, persistent in its vertical distribution. The manner of occurrence of secondary minerals is frequently characteristic; secondary minerals, being due to the action of surface waters, are commonly found in cracks through earlier minerals, or as crusts lining vugs or surrounding nucleal masses, or in general, in some distribution later than and not conforming to the arrangement of the primary minerals. Secondary sulphides are often found as soft black pulverulent masses or coatings, although they frequently occur well crystallized or as

Jan 1, 1932

By Aaron J. Miles, Eugene A. Stepenson

The pressure distribution in a producing oil or gas reservoir has been obtained mathematically in a limited number of special cases where the boundary of the reservoirs are simple geometric figures with the wells conveniently located within them. Using some of the previous work as a basis, it can be proved that a number of additional problems of pressure distribution can be solved by use of soap film. This method is particularly applicable to a reservoir drained by a number of wells, or to a reservoir of irregular shape, or to both. Since this method obtains the pressure distribution, it also establishes the drainage boundaries of the wells. This paper derives the analogy between the equation representing the pressure distribution in a reservoir and the equation of the deflected membrane. It also describes the apparatus and the method of operation. The experimental method is employed to solve a problem whose mathematical solution is known and the results compared. These are found to be in good agreement. The method is applicable to any homogeneous liquid, compressible or incompressible, or to a gas, flowing in a reservoir of uniform thickness, permeability and porosity. The flow state may be either the steady state or the transient state wherein the density or pressure of the fluid in the reservoir declines at a constant rate. PRESSURE-DISTEIBUTION PBOBLEM Fluids encountered in the oil reservoir are compressible and expand and move toward the drilled hole where the Dressure is lowest. The loss of fluid from the reservoir lowers the pressure in the more distant parts of the reservoir, permitting the fluids in these parts to expand and move toward the well. The area around the well affected by drainage is increasing continuously, and the density, pressure, and velocity of flow

Jan 1, 1938

By Thomas D. West

The fact that iron expands when heated, until fusion takes place, and that molten iron is consequently less dense than solid iron of the same grade, is now universally admitted. It was proved by the extensive experiments of Mr. Thomas Wrightson, reported in the Jownal of the Iron and Steel Institute (1890, No. 1, p. 72, and 1891, No. 1, pp. 75, log), and, in a manner, is illustrated in heavy founding by the shrinkage 'of the molten metal, which must be " fed " in order to obtain solid castings. This decrease in volume requiring " feeding" while the metal is still liquid I call " shrinkage," applying the term " contraction" to the decrease in volume which takes place after solidification, while the iron is cooling to atmospheric temperature. The light-work founder, not having the opportunity to make heavy castings, in which shrinkage can be observed, is apt to confound the two; but they are in fact distinct, and are separated by an act of expanion, which takes place at the moment of solidification. The fact of this expansion was first practically demonstrated by Mr. John R. Whitney, of Philadelphia, Pa., whose experiments are recorded in the National Car and Locomotive Builder of May, 1889. Experiments recently made by the writer indicate that there is a constant relation between this expansion and the preceding shrinkage and forcibly demonstrate the necessity of " feeding " a casting to make its interior solid. This is a matter with which all makers and users of castings have experienced difficulty. The founder being heretofore unable to define correctly the principles involving the urgent necessity of " feeding " has failed to impress the moulder with its importance in making sound castings.

Jan 1, 1897

By Joseph G. Debanné

Foreword The three case histories and the liquid fuels planning scenario presented in this paper span a twenty year period, from the pioneering days of computers in the petroleum producing industry during the mid-fifties, to the energy crisis era of the seventies. Inasmuch as two of the main actors, Ian McKinnon and I, are featured in all three case histories, while I am currently involved in the fossil fuels scenario, this paper provides four related and personal spot readings along an evolutionary path: from the one dimensional technical domain to the multi-dimensional techno-socio-economic domain of computer applications in the petroleum industry. Coincident with this evolution in the direction of increasingly comprehensive and powerful computer applications, the evolution in hardware/software capability and in analytical power are also kept in perspective. The three case histories are: 1. The Bonnie Glen-Wizard Lake Case (Calgary, Alberta, 1955-1957); 2. The TransCanada-Great Lakes Gas Transmission Case (Ottawa-Washington, 1966); 3. The Westcoast Transmission - El Paso Pipelines Gas Export/ Import Case (Ottawa-Vancouver-Washington, 1966-1967). The liquid fuels planning scenario is a demonstration exercise rather than a case history; however, it represents an important point on the evolutionary curve and, provides a concrete example of tech-

Jan 1, 1977

ALABAMA America.-Foreman, J. T. Ashland.-Sturdevant, J, C. Altalla; Henderson, R. M. Bessemer.-Ball, E. M. Maschmeyer, W. L. McKenzie, W. C., Jr. Birmingham.-Abbott, C, E. Aldrich, T. H. Aldrich, T. H., Jr. Aufderhaar, H. C. Berg, H. A. Blair, C. S. Bush, M. W. Clark. G. H.

Jan 1, 1929

By S. M. Parmley

Experience has shown that there are some factors connected with the drying of fine washed coal that are not present in drying of slack coal as normally practiced at cement kilns or pulverized coal plants. It is the purpose of this paper to show some of these variations as they have been encountered under actual operation. The Champion No. 1 cleaning plant of the Pittsburgh Coal Co. uses the wet system of cleaning coal. The plant is equipped to produce commercial sizes or mixtures, the primary sizes being plus 6 in. and 4 by 6 in., which are hand-picked. Minus 4-in. sizes are all cleaned by the wet process. To produce a commercial product as free of moisture as possible, the washed coal is first passed over sizing and dewatering screens, then each size except the — ?-in. coal is conveyed to loading booms by slow-moving draining conveyors. As the +?-in. sizes are not heat-dried, no data will be given, as it is the purpose of this paper to describe the heat drying of — ?-in. coal as practiced at the Champion No. 1 plant of the Pittsburgh Coal Company. To fully appreciate the conditions, it must be remembered that the — ?-in. product is now shipped at a lower moisture content than when received from the mine. The incoming coal in the — ?-in. size will average 5 per cent. moisture and the shipped product 3 per cent. moisture. This is a case where a wet process gives a reduction of both ash and moisture in the fine sizes. The shipped product, therefore, is more uniform in all characteristics, and uniformity of product is the most important single factor in coal preparation. The 0 by ?-in. coal is first dewatered on slow-moving continuous bucket dewatering elevators, running at the rate of 40 ft. per minute, with 48-in. perforated buckets with ¼ by 1½-in. slots, spaced ? by 2?-in. centers staggered. The moisture in the coal discharged from the elevators runs 20 to 28 per cent., depending on the fineness of the product. The discharge from the dewatering elevator is further drained on a drag-type conveyor equipped with ½-mm. wedge wire screen. The conveyor discharges coal with an 18 to 25 per cent. moisture to three centrifugal dryers of the Carpenter type. The Carpenter dryers

Jan 1, 1931

By W. F. Cloud

The data and information compiled under Part I of this report are the results of experiments performed in the petroleum engineering laboratory under the supervision of W. F. Cloud, Associate Professor of Petroleum Engineering and William Schriever, Professor of Physics, University of Oklahoma. Problems Being Studied Most of the time has been spent in trying to determine the rate of flow and pressure gradient in a 4-in. flow tube 10 ft. long, which was packed with sand of various grain sizes. To date, only two kinds of sand have been packed in this tube: 60 to 80-mesh Canadian river sand, 60 to 80-mesh and 80 to 100-mesh Simpson sand. The original intention was to follow the same procedure and use the same types of crude under identical saturation pressures of both air and gas, as well as unsaturated (dead) oil, flowing the various crudes through several different sizes of both Canadian river and Simpson (Wilcox) sands, but lack of time has prevented such an intensive study of the problem. Some additional time has been spent flowing saturated and unsaturated crudes, similar to those used in the 4-in. tube, through 1-in. tubes, one of which was 2 ft. long and one 5 ft. long. The results obtained have been checked against those obtained by using the 4-in. tube, to obtain the relation of diameter and length of tube to rate of flow in similar sands. Laboratory Equipment Saturation Tank.—A heavy steel cylindrical saturation tank, capacity about 42 gal. was mounted on a platform of bricks, then a galvanized tin temperature bath was built around the saturation tank. This contained

Jan 1, 1930

By E. S. Grumell

THE correct sampling of coal and coke is becoming important to an ever increasing number of producers and consumers. This, therefore, may be an opportune moment to examine where we stand with regard to existing and proposed methods. In this paper an attempt will be made to review, as briefly as possible, some of the considerable amount of painstaking research which has been done in the last 10 years, and which has unquestionably led to a much better understanding of the subject. In so doing we shall try, on the one hand, to make clear where substantial progress has been made, and on the other hand, to draw attention to points that require further investigation. The paper is divided into sections in order to emphasize the major divisions of the subject; further, in order to retain this emphasis, detailed consideration of some of the points has been relegated to appendixes. No attempt has been made to give a complete survey of the literature, as this has already been done by L. A. Bushell.2 The following abbrevia-tions will be used: A.E., average error; P.E., probable error; S.W.R., size-weight ratio; B.S.I., British Standards Institution.

Jan 1, 1939

By Herbert D. Drechsler

Mining Finance-is the interrelated aspects of "determining the total amount of funds to employ in a mining firm; allocating these funds efficiently to various assets; and, obtaining the best mix of financing in relation to the overall valuation of the firm". The first section is an overview of the financing problem through examination and discussion of the Balance Sheet and Income Statement. The next section is a discussion of the nature of the criteria developed in feasibility study. The third section describes type of capital funds, and the final section describes case studies of mining finance.

Jan 1, 1978

By Robert Glass Cleland

THE MEMBERS of the Phelps-Dodge, Phelps-James co- partnership differed widely from one another in certain aspects of temperament and personality; but in one thing Anson Phelps, William Dodge, and Daniel James were fundamentally alike. They were all bred in the English Puritan tradition. Their creed, moreover, was the stern, militant, uncompromising creed of John Calvin and John Knox. The present generation, harshly intolerant of such a creed, has little understanding of the authority it exercised on the thinking and conduct of its adherents or of the contributions that those same adherents made to human welfare and social progress. The men who accepted its authority "were characterized by a blend of strong individualism and an equally strong sense of social duty, and they submitted their own souls to the same searching scrutiny that they applied to their business ledgers." To all three of the immediate founders of Phelps Dodge, their religion was the most real and important thing in life. It was with them day and night, in joy and sorrow, in loss and prosperity, in their most trivial personal affairs, in business transactions of the greatest moment. It was with

Jan 1, 1952

By J. G. Thompson

OXYGEN, nitrogen and hydrogen are present in' practically all metals in one or more of the following forms: (1) molecular gas in blowholes or blisters, (2) combined in nonmetallic inclusions such as nitrides, oxides or silicates, and (3) in solid solution in the metal. Gaseous elements, in some of these forms, are encountered in practically all metals and alloys but possibly have received most publicity in connection with iron and steel. In fact, the entire steel industry depends upon the control of the oxygen content during the refining process, as well as in the finished material, and it was only after the adoption of the use of efficient deoxi-dizers such as manganese that the production of good steel with a low carbon content became possible. In normally clean, sound steel the amount of hydrogen is negligible and the amounts of oxygen and nitrogen vary from a few thousandths to a few hundredths per cent. However, many of the effects attributed(27,31,40,41,53,54,55.56,62) ? to the presence of these elements are important and at first glance appear to be out of proportion to the amounts of impurities involved. The presence of oxygen is believed to affect the solubility of carbon in austenite and ferrite and thereby to affect the structure of the iron or steel. Such properties as strength, hardness, ductility, elastic .limit, impact resistance, magnetic permeability, tendency toward caustic embrittlement, irregularity in carburization, the cutting life of, tools, certain corrosion phenomena, the presence of flakes, seams, bands, ghost lines and hair cracks, and the tendency to age-harden, all have been attributed to the presence of oxygen.

Jan 1, 1932

By Arthur V. Abbott

In a few places attempts have been made to introdnce some means of delivering heat from a central station. Probably Pittsburgh, through the advantages derived from its almost inexhaustible supply of natural gas, has made a more wide-spread success in this direction than any other city. From the gas-wells in the vicinity of that town an enormous supply of natural gas can readily be obtained at a pressure sufficient to force it many miles from its source and to distribute it to all consumers. Obviously, very few places have such natural advantages, and some other means must be devised, if it is desired to furnish heat in a location not supplied with gas-wells. Several plants have been introduced to deliver heat by

Jan 1, 1888

By J. B. Warriner

Introduction STRIPPING is the name given to the process of removing clay, rock, or other cover from deposits of coal or ore. In this paper it is intended to cover the methods used in carrying on this operation in the anthracite coal regions of Pennsylvania. In doing this, attention will be chiefly devoted to those methods wherein practice in different sections of the region differs, or is susceptible to change or improvement, though it is intended to give as complete data as possible concerning all stages of the operation. The data from which this paper has been prepared have been collected and submitted by a committee representing the larger users of stripping methods, of which committee the writer has acted as chairman. Data and assistance have also been obtained from various mining men, engineers, contractors and manufacturers of stripping equipment, to all of whom our appreciation is clue.

Jan 1, 1917

By Morris Cohen

Within the past two years, a number of publications have called attention to the double peaks, or stages, that appear in the hardness and strength curves of certain aging alloys. The author has shown the existence of double hardness peaks during the aging of a high-purity silver-copper alloy;' and on the basis of electrical resistance, microscopic, dilation and lattice-parameter measurements, hc concluded that the initial hardness peak occurs prior to precipitation while the secondary hardening is due to precipitation. It was suggested that the general mechanism of age-hardening involves two consecutive processes, the first consisting of nucleus or knot2 formation, and the second consisting of actual precipitation and particle growth. It was further held that the two stages are interdependent, but because of nonuniform precipitation they may overlap each other to an extent that increases as the aging temperature is raised. At high aging temperatures, the effect of the first stage cannot be detected because of the rapid occurrernce of precipitation. The general theory of age-hardening recently presented by Dr. M. L. V. Gayler3 is in close agreement with the picture outlined above. With reference to work done on duralumin, copper-beryllium and copper-silver alloys, Dr. Gayler also concluded that age-hardening takes place in two consecutive steps: first, diffusion (in which the solute atoms migrate to certain crystallographic planes), and then precipitation. However, W. L. Fink and D. W. Smith4 have shown that the double aging peaks that appear in the strength curves of high-purity aluminum-copper alloys may be explained without recourse to pre-precipitation phenomena. By means of very careful metallographic technique, Fink and Smith demonstrated that during aging the precipitation takes place at an accelerated rate along the grain boundaries and slip planes as a result of the plastic deformation caused by the drastic quench from the solution heat-treatment temperature. The general precipitation occurs at a

Jan 1, 1939

By G. C. Gould

The nature of freckle segregation is determined by chemical analyses, microradiograplzy, and electron microprobe. In addition, the influence of chemistry variation on freckle formation is studied in laboratory experiments. It is demonstrated that controlled laboratory solidification can produce freckle segregation. "FRECKLE" segregation is a discontinuous, rod-like segregation observed in vacuum consumable -electrode ingots. Figs. 1 and 2 show this segregation as pencil-like, dark etching areas of segregation found in longitudinally and transversely sectioned consumable-electrode ingots. In most cases the segregation is perpendicular with respect to gravity and parallel to the longitudinal axis of the ingot. The segregation is most often encountered at or around midradius in large vacuum consumable-electrode ingots. The austenitic alloys, A-286* and 718, † have shown particular susceptibility to this mode of segregation. The origin of these rodlike pockets of segregation is not well-understood. It has been suggested that the segregation is a result of a portion of the electrode dropping off and passing through the arc un-melted. On the other hand, smeltzer1 has demonstrated the freckle segregation in A-286 to be comprised of low-melting constituents relative to the matrix melting point. The discontinuous nature of the segregation is the most perplexing facet of the freckle-segregation problem. It was to gain some insight into this part of the problem that this work was undertaken. I) PROCEDURE At the outset of the work identification of the phases present and the elements concentrated in the freckle areas was undertaken. The electron micro-probe was used to determine general enrichment as well as -specific phase chemistry. Microradiography using cobalt and chromium radiation was also used on the freckle areas again to determine the elements involved in the segregation. X-ray diffraction patterns were made from portions of these same foil specimens. Optical microscopy and Knoop hardness measurements were also used

Jan 1, 1965