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By W. C. Ellis

NONFERROUS alloys upon which desirable properties can be conferred by heat treatment are becoming of increasing industrial importance. The alloys of copper with a constituent which has a solubility varying with temperature are materials of this character. Some of the constituents which are effective in producing a change in the mechanical properties of these alloys upon heat treatment are, according to Corson,1 nickel and silicon, iron and silicon, cobalt and silicon, and chromium and silicon. In addition to these elements, Gregg2 states that the combination of beryllium and silicon is effective in producing age-hardening characteristics in copper. The effect of these elements, however, as dispersion-hardening constituents in the copper alpha solid solutions does not seem to have been studied in any considerable detail. This paper deals with the heat treatment and properties of three alpha brasses containing 3 per cent. of nickel plus silicon in the proportion necessary to form the compound nickel silicide, Ni2Si. Some information of a preliminary nature in regard to the hardening by heat treatment of phosphor bronze containing the same percentages of nickel and silicon is included. The method of hardening the alloys, which is effective in increasing the tensile strength and proportional limit, is similar to that used in, the case of duralumin type aluminum alloys. It consists of a quench from a temperature at which the hardening constituent is in solid solution, followed by an aging at a lower temperature to precipitate the dissolved constituent in a dispersed condition. This results in an increased resistance of the alloy to deformation with an attendant improvement in the tensile properties.

Jan 1, 1929

Executive SIDNEY .J. JENNINGS, Chairman GEORGE D. BAR HON .I. E. JOHNSON, JR. EDWIN LUDLOW ROBERT M. RAYMOND Membership KARL EILERS, chairman LEWIS W. FRANCIS .1. E. JOHNSON, JR. LOUIS D. HUNTOON ARTHUR. L. WALKER Finance GEORGE D. BARRON. Chairman. CHARLES F. RAND BENJAMIN B. THAYER Library E. GYBBON SPILSBURY1 Chairman ALEX C. HUMIPHREYS3 GEORGE C. STONE .J. H. JANEWAY4 BRADLEY STOUGHTON Papers and Publications BRADLEY STOUGHTON, Chairman

Jan 10, 1918

By Reginald E. Hore

Since the discovery of silver at Cobalt, Ontario, in August, 1903, more than 100,000,000 oz. of silver have been produced by the mines in the Nipissing district, and there is reason to believe that at least as much more will be produced in the nex five years. The estimated value of the aggregate output o ore to the end of 1910 is $48,327,280. The ore yielded 93,977,833, oz. of silver and was mined at a net profit of abou $16,000,000. For 1910 the production was 30,558,825 oz., valued at $15,436,894, and yielding a profit of about $9,000.000. The details of the production of the Cobalt district for the years 1904 to 1909, inclusive, as reported by the Ontario Bureau of Mines, are given in Table I. The shipments from Cobalt are in the form of smelting-ore, concentrates from milling-ore, and bullion. The smelting-ore is largely high grade, averaging about 3,000 oz. per ton A smaller return is from what is called low-grade ore and which

Jan 1, 1912

By Henry F. Hebley

This paper brings within the compass of one comparatively brief article a general description of the situation concerning the nation's water resources. It touches upon the phenomenal growth in the demand for water supply and emphasizes the problems facing the coal industry both with regard to acid mine water drainage discharged from active and abandoned mines and the suspended solids discharged to the stream system from wet coal preparation plants.

Jan 4, 1953

Discussion of the paper of FRANCIS S. PEABODY, presented at the St. Louis meeting, October, 1917, and printed in Bulletin No. 125, May, 1917, pp. 775 to 781. THE CHAIRMAN (CARL SCHOLZ, Chicago, I11.).-Coal wastage is undoubtedly one of the most prominent topics before the coal operators of the United States today. Even those who have been in the business only 25 years, like myself, know that the exhaustion of coal is something that should and must, be curbed. If it is not, before long we shall discover that the great coal resources of the country are not what we-thought they were; we have been so accustomed to work at the best and thickest coal alone, that it will be difficult for us to realize one of these clays-and that (lay is not far distant-that we are no longer the rich nation in coal that we thought we. were. In this connection I feel obliged to attach a little blame to the Geological Survey for misleading the people. There are several members ,here who assisted in that work, and I am going to ask them to defend themselves. The Geological Survey deals with coal seams of much less thickness than we could now expect to, mine, particularly with the present high wages, excepting at a prohibitive cost. The Geological Survey, in its estimates, does not discriminate between thick and thin seams, but simply estimates our resources at so many hundred thousand billion tons of coal. I believe they include seams from 15 to 18 in thick, but you all know that a vein below 3.5 or 4 ft. is not considered economical to mine at this time. R. V. NORRIS, Wilkes-Barre, Pa.-Mr. Peabody has evidently been thinking almost entirely of Illinois conditions, with which I regret to say I am absolutely unfamiliar. In some West Virginia mines the total recovery at present is considerably over 90 per cent. and extraction-, as high as 97 or 98 per cent. are claimed.

Jan 1, 1918

By S. W. Zehr, G. S. Murty, W. A. Backofen

AN observation by Squires, Weiner, and phillipsl has stimulated interest in a mechanism of deformation at high temperature (above -0.5 of the absolute melting point) that is not usually thought to be involved in the creep of metals. They found precipitate-free or "denuded" zones along grain boundaries normal to the stress axis in tensile specimens of a hydrided Mg-1/2 wt pct Zr alloy after slow straining at 450° and 500°C. Their suggestion that the zones were a result of directional diffusion of magnesium atoms was supported with calculations from Harris and Jones2 which also tended to identify the process as Nabarro-Herring (N-H) creep3,4—a process that is characterized by Newtonian viscosity, with stress (o) directly proportional to strain rate (C), and one that proceeds by lattice diffusion. Material transport by diffusion along grain boundaries is an alternative basis for Newtonian viscosity, as demonstrated by Coble,5 and is favored over N-H creep for fine grain size and lower temperature.6 In either case, the strain rate sensitivity of flow stress, defined as m = d log o/d log E (which commonly appears in the empirical a = KEW), is unity. The experiments to be described here gave metallo-graphic indications of diffusional creep which were no less clear than those just cited, but the associated m (as measured by the method of Ref. 7) was much more like that of a Bingham material. For true Bingham behavior, (a — ao) E, where oo is an initial yield stress. Therefore, even if flow after yielding should occur by diffusional transport, m must increase from 0 as < is raised to reach unity only in the limit as One result is that the resistance to tensile necking conferred by Newtonian viscosity is lost, which would become increasingly apparent through the formation of more sharply defined necks as 6 is lowered. That trend appeared in these experiments. Most of the work was done on an extremely finegrained alloy of magnesium with -6 wt pct Zn and ½ wt pct Zr (Mg ZK60); the initial mean-intercept grain diameter, L, was 0.55 µ. Shown in Fig. l(a) is a germanium-shadowed carbon replica of the surface of a specimen that was coated with silicone oil,* heated to 270°C under a helium atmosphere, and then stretched locally -200 pct at an initial E = 3.3 x 10-5 sec-1. Under

Jan 1, 1969

By H. F. Johnson, C. S. Harloff

The Nichols series system of electrolytic copper refining has successfully maintained its strong competitive position in the copper-refining industry of today; therefore the improvements made in accomplishing this result are of interest. While additional interest would lie in specific comparisons of results obtained in series operation with those in multiple, we have refrained from such a comparison because it can be fair to both only when they are operating under similar conditions on the same grade of materials. Historical The Nichols Copper Co. started a small refinery at Laurel Hill, using its present system, about 1892. The details of the process in its early stage of development were kept strictly secret, so that no information was published or interchange of ideas permitted with the staffs of other copper refineries, where the multiple system was being developed at the same time. However, the fundamentals of the process and type of cell used today differ very little from their earliest form. All operations including loading and unloading of tanks, and all transportation as well, were carried on by hand. The plant remained in this condition with a gradual expansion taking place until the World War forced such a rapid development that little time or thought could be devoted to modernization or mechanical improvement requiring careful design or detailed planning. Considerable progress was made, however. (1) Large refining furnaces were developed. (2) The old expensive air-lift type of circulation was abandoned in favor of the present system. (3) Operating technique was gradually developed to a high point of efficiency. (4) Tank construction and lining were greatly improved, the first concrete tank being installed in 1915. (This tank is still in operating condition.) (5) A new power plant was constructed. (6) Fuel oil was substituted for lump coal on the refining furnaces. (7) Mechanical casting of the finished product was accomplished. During this entire period the plant was particularly fortunate in receiving only high-grade, clean copper bullion coming principally from the Phelps Dodge mines in Arizona. This, together with the lack of

Jan 1, 1934

By L.W. Eastwood, Arthur E. Bousu, C. T. Eddy

The recrystallization and grain-growth phenomena of cold-worked metals have considerable industrial importance because of their role in the fabrication of metals. For this reason, and because of the general academic interest in the subject, these processes have received considerable attention since the time of J. E. Stead&apos;s paper1 on The Crystalline Structure of Iron and Steel. There are considerable differences of opinion regarding the theory of recrystallization and grain growth and also differences in the observation of the modus operandi of the processes themselves. The value of many of the existing quantitative data on grain growth is decreased by the failure to distinguish between the grain sizes just after complete recrystallization and those resulting from coalescence. For this reason also, the value of the diagrams of stable grain sizes, like those produced by Bass and Glocker2 and Czochralski3, is lessened in so far as an interpretation of the facts of recrystallization is concerned. It is hoped that the data presentcd in this paper will help to clarify and to simplify the facts relating to recrystallization, and at the same time will show that some of the present-day conceptions are untenable. A paper on the theory of recrystallization, with additional data, will be completed in the near future by the writers. Since the literature on the subject has been adequately and frequently reviewed, the only referenccs to it in this paper will be those necessary in the discussion of the data presented.

Jan 1, 1935

By W. C. Maurer

Although millions of feet of rock are drilled annually, the basic drilling mechanisms involved are not well understood. The primary reason for this lack of knowledge is because the basic principles of rock failure are not well understood and rock failure is the primary mechanism in drilling. A better understanding of the drilling mechanisms would enable a more scientific approach to the design and use of drills and bits. The paper reviews several models which have been proposed to explain various aspects of the different drilling methods. These models are described and their limitations and areas of application are discussed. Drilling rate relationships are developed and related to the basic rock failure mechanisms. TYPES OF MECHANICAL DRILLS There are three basic methods of mechanically attacking rock: 1) percussive action, 2) rotary action, and 3) combined rotary-percussive action. A percussion drill applies a force perpendicular to the rock surface and the bit moves into the rock perpendicular to the surface, forming a crater beneath it (Fig. 1). A rotary drill applies a constant thrust to the bit while a torsional force moves the bit parallel to the rock surface, breaking the rock ahead of it. A rotary-percussive drill applies both a rotary force and a percussive force to the bit which moves into the rock at an angle to the surface. The commonly used drills can be classified as: rotary-drag, diamond; percussive-hammer, piston, churn; and combination-rotary-percussive, roller.

Jan 1, 1967

By Arthur E. Bousu, C. T. Eddy, L. W. Eastwood

The recrystallization and grain-growth phenomena of cold-worked metals have considerable industrial importance because of their role in the fabrication of metals. For this reason, and because of the general academic interest in the subject, these processes have received considerable attention since the time of J. E. Stead&apos;s paper1 on The Crystalline Structure of Iron and Steel. There are considerable differences of opinion regarding the theory of recrystallization and grain growth and also differences in the observation of the modus operandi of the processes themselves. The value of many of the existing quantitative data on grain growth is decreased by the failure to distinguish between the grain sizes just after complete recrystallization and those resulting from coalescence. For this reason also, the value of the diagrams of stable grain sizes, like those produced by Bass and Glocker2 and Czochralski3, is lessened in so far as an interpretation of the facts of recrystallization is concerned. It is hoped that the data presentcd in this paper will help to clarify and to simplify the facts relating to recrystallization, and at the same time will show that some of the present-day conceptions are untenable. A paper on the theory of recrystallization, with additional data, will be completed in the near future by the writers. Since the literature on the subject has been adequately and frequently reviewed, the only referenccs to it in this paper will be those necessary in the discussion of the data presented.

Jan 1, 1935

By E. H. Rennhack

Phase equilibria of the zinc-rich portion of the Zn-Fe-A1 system containing up to 20.0 wt pct Fe and Al have been investigated at 600°C (1112°F), 450°C (842°F), and room temperature by metallographic and X-ray diffraction techniques. The phase relationships were found to involve only those phases present in the three binary systems. THE presence of small quantities of aluminum (approx. 0.2 wt pct*) in zinc galvanizing baths is known to suppress the formation of Zn-Fe alloy layers within the coating.&apos; As part of an extended investigation of this suppression effect and the alloy reactions involved, the zinc-rich corner of the Zn-Fe-A1 equilibrium system containing up to 20.0 pct Fe and Al was determined at 600°C (1112°F), 450° F (842° F), and room temperature. The present paper reports the findings of this study. The constitution of the Zn-Fe system has been reported by Raynor2 based mainly on the work of Schramm3-3 and Truesdale et a1.6 The solid solubility of iron in zinc is extremely small and lies between 0.0009 and 0.0028 pct in the range 150° to 400°C (302°to752°F). Within the temperature and composition range of interest, a eutectic reaction involving nearly pure zinc, liquid = Zn+FeZn13, is observed at about 419°C (786° F) and 0.018 pct Fe along with a peritectic reaction, FeZn7+ liquid e FeZn13, at 530°C (986° F) and 6.2 pct Fe. The latter reaction is sluggish due to the large proportipn of solid phase involved in the transformation. Halla et al.,7 identified the compound FeZn13 as monoclinic with a = 13.68, b = 7.63, c = 5.07, and B = 128°44&apos;. The structure of FeZn7 was reported by Bablik, et al.,8 to be of hexagonal symmetry, belonging to either the C6v = C6/m mc or D46h = C6/mc space group. Divensions of the unit cell are a = 12.81A and c = 57.6a. The Zn-A1 diagram as composed by Raynor9 and later Gebhardt10 is characterized by a eutectic decomposition, liquid 382°C (720°F) and 95.0 pct Zn and a eutectoid decomposition, at 275° (527°F) and 78.0 pct Zn. The eutectoid reaction cannot be suppressed permanently by quenching. Above 275° (527° F), a and a&apos; co-exist in a closed miscibility gap between 31.6 and 78.0 pct Zn. Both phases are fcc and have nearly the same lattice parameter. The maximum solubility of aluminum in zinc (B) is approximately 1.0 pct at the eutectic temperature. PROCEDURE Materials. The experimental alloys were prepared from both massive and powdered material. Cast alloys were composed from three zinc-base master alloys containing 8.0 pct Fe, 16.0 pct Fe, and 50.0 pct Al which were made from C.P. zinc, Armco iron, and

Jan 1, 1962

By W. P. Heineken, A. T. Child

This paper presents the results of a series of experiments made in the metallurgical laboratory of Columbia University, New Pork City. The object of the investigation was to determine, as far as possible, the changes in micro-structure and physical properties caused by short periods of heat-treatment and the longer malleable cast-iron process. It was proposed to do this by means of micro-photographs, heating- and cooling-curves, and tensile tests after the various heat-treatments. I. Micro-Constituents of Iron and Steel. The list of the micro-constituents of iron and steel has grown till now it includes seven different substances, called ferrite, cementite, pearlite,* martensite, austenite, sorbite and troosite. Only the first five of these are mentioned in this paper, to facilitate the understanding of which, the following brief definitions are given: 1. Ferrite (named by Prof. Howe) is, chemically, iron free from carbon. It is the softest of the constituents, and is not colored by etching, except when long-continued. Under the microscope it is easily determined by its regular polygonal etructure; or, if structureless, as in malleable cast-iron, by the ease with which it is scratched. Ferrite appears in mild steel in small amount, in grey cast-iron, and in malleable cast-iron. 2. Cementite (also named by Prof. Howe) is now generally conceded to have the formula Fe3C. It is the hardest of the micro-constituents, having the hardness indicated by 7 of the mineralogical scale; and hence it is always left in relief after

Jan 1, 1901

By R. S. Busk, R. F. Marande

The magnesium-aluminum-zinc &apos;system contains most of the magnesium-base alloys used commercially, although in practice the ternary alloys are usually modified by the addition of a small amount of manganese. Table I contains the magnesium-base commercial sand-casting alloys most widely used throughout the world, together with their typical tensile properties. These alloys may be regarded as a single family of varying aluminum and zinc content, disregarding manganese. A concise means of presenting data for them is by means of iso-property lines plotted on triangular coordinate paper. Constitutional, casting, and mechanical properties are presented in this manner. The data are given with the obiect of providing reference material, and to aid in the choice of a commercial alloy to serve a particular purpose. Detailed, critical analysis of the commercial alloys has been covered in a previous paper.&apos; All alloys reported were made in rj-lb. melts, superheated to r700°F. for 15 min., cooled to r400°F. and poured in sand molds. The test bars produced had a 1/2-in. reduced section and were about 6 in. long. Except for the data represented in Figs. I and 3 the alloys used were of commercial purity and contained 0.1 to 0.2 per cent Mn in addition to the aluminum and zinc. Constitutional Data Under the heading of Constitutional Data are included all known data on con-

Jan 1, 1946

By R. F. Marande, R. S. Busk

The magnesium-aluminum-zinc &apos;system contains most of the magnesium-base alloys used commercially, although in practice the ternary alloys are usually modified by the addition of a small amount of manganese. Table I contains the magnesium-base commercial sand-casting alloys most widely used throughout the world, together with their typical tensile properties. These alloys may be regarded as a single family of varying aluminum and zinc content, disregarding manganese. A concise means of presenting data for them is by means of iso-property lines plotted on triangular coordinate paper. Constitutional, casting, and mechanical properties are presented in this manner. The data are given with the obiect of providing reference material, and to aid in the choice of a commercial alloy to serve a particular purpose. Detailed, critical analysis of the commercial alloys has been covered in a previous paper.&apos; All alloys reported were made in rj-lb. melts, superheated to r700°F. for 15 min., cooled to r400°F. and poured in sand molds. The test bars produced had a 1/2-in. reduced section and were about 6 in. long. Except for the data represented in Figs. I and 3 the alloys used were of commercial purity and contained 0.1 to 0.2 per cent Mn in addition to the aluminum and zinc. Constitutional Data Under the heading of Constitutional Data are included all known data on con-

Jan 1, 1946

By T. R. Lippard

PURE gypsum may be broken down into its constituents as follows: [ ] Standard specifications (ASTM Designation C22-25) state that a material shall not be considered gypsum if it contains less than 64.5 pct by weight of CaS042H2O. Anhydrite, the second calcium sulphate mineral found in nature, may be broken into its constituents as follows: [ ] PROPERTIES OF GYPSUM AND ANHYDRITE Pure gypsum is colorless to white but various impurities change its color to shades of gray, brown, red, or pink. It has a hardness of 2 in the Mohs scale and can be scratched with the fingernail. The specific gravity of pure gypsum is 2.3 to 2.4, so that rock gypsum, free from moisture, weighs about 145 lb per cu ft. Gypsum crystallizes in the monoclinic system in tabular crystals that exhibit good cleavage

Jan 1, 1949

By E. R. Parker, D. L. Martin

In a previous paper one of the authors observed that the rate of cooling from the anneal prior to testing greatly influenced the life of copper under sustained load at 200°C. Furnace-cooled bars of oxygen-free copper (with and without silver) had a life four to twenty-five times that of the water-quenched specimens. The addition of 0.054 per cent silver to the oxygen-free copper increased the life at a stress of 20,000 lb. per sq. in. from about 2 hr. to 50 hr. Fractures in these bars were intercrystalline. An explanation was advanced to account for the profound influence of cooling rate on the rupture properties at 200°C. The suggestion offered was that at the high annealing temperature the minor constituents are distributed at random. By water quenching, this condition is maintained at room temperature, whereas furnace cooling permits some segregation at the grain boundaries. The higher concentration of the minor constituents in the grain boundaries results in a. strengthening, so that a longer life at a given stress and .temperature results. Small amounts of cadmium or manganese have also been found to increase the life of copper at 200°C., and to a much greater extent than silver.2 The increase in the long-time strength of copper resulting from small additions of cadmium or silver appears to be related, indirectly at least, to the higher softening temperatures of such alloys. The elements, such as silver or cadmium, which greatly increase the rupture life of copper also cause large increases in the softening temperature. As little as 0.05 per cent of cadmium or silver is sufficient to raise the softening temperature more than 100°.3,4 The effects of cooling rate and of minor constituents on the rupture properties are of considerable fundamental as well as practical interest; therefore a more detailed study of their nature was conducted and is reported in this paper. Experimental Procedure Materials The materials studied in this investigation may conveniently be classified in two groups: one consisting of a wide variety of commercial coppers, and the other composed of special high-purity, laboratory-prepared coppers. The commercial materials were tested to determine whether or not the effect of cooling rate occurred with all coppers, whereas the high-purity coppers were investigated in order to establish a basis for evaluating the effect of minor constituents on the rupture properties. In Table I are given the analyses of the coppers tested. The samples I to 6 are commercial materials and were obtained for the most part from stock supplies.*

Jan 1, 1944

By D. L. Martin, E. R. Parker

In a previous paper one of the authors observed that the rate of cooling from the anneal prior to testing greatly influenced the life of copper under sustained load at 200°C. Furnace-cooled bars of oxygen-free copper (with and without silver) had a life four to twenty-five times that of the water-quenched specimens. The addition of 0.054 per cent silver to the oxygen-free copper increased the life at a stress of 20,000 lb. per sq. in. from about 2 hr. to 50 hr. Fractures in these bars were intercrystalline. An explanation was advanced to account for the profound influence of cooling rate on the rupture properties at 200°C. The suggestion offered was that at the high annealing temperature the minor constituents are distributed at random. By water quenching, this condition is maintained at room temperature, whereas furnace cooling permits some segregation at the grain boundaries. The higher concentration of the minor constituents in the grain boundaries results in a. strengthening, so that a longer life at a given stress and .temperature results. Small amounts of cadmium or manganese have also been found to increase the life of copper at 200°C., and to a much greater extent than silver.2 The increase in the long-time strength of copper resulting from small additions of cadmium or silver appears to be related, indirectly at least, to the higher softening temperatures of such alloys. The elements, such as silver or cadmium, which greatly increase the rupture life of copper also cause large increases in the softening temperature. As little as 0.05 per cent of cadmium or silver is sufficient to raise the softening temperature more than 100°.3,4 The effects of cooling rate and of minor constituents on the rupture properties are of considerable fundamental as well as practical interest; therefore a more detailed study of their nature was conducted and is reported in this paper. Experimental Procedure Materials The materials studied in this investigation may conveniently be classified in two groups: one consisting of a wide variety of commercial coppers, and the other composed of special high-purity, laboratory-prepared coppers. The commercial materials were tested to determine whether or not the effect of cooling rate occurred with all coppers, whereas the high-purity coppers were investigated in order to establish a basis for evaluating the effect of minor constituents on the rupture properties. In Table I are given the analyses of the coppers tested. The samples I to 6 are commercial materials and were obtained for the most part from stock supplies.*

Jan 1, 1944

By David B. Burrows, Rlkl Kobayashi, Norman L. Carr

The viscosity of hydrocarbon mixtures, whether in the gas or liquid phase, is a function of pressure, temperature, and phase composition. This paper presents methods for the prediction of the viscosity of the gas or less dense fluid phase over the practical range of pressure, temperature, and phase compositions encountered in surface and subsurface petroleum production operations. The correlation necessary to predict the effect of pressure on viscosities is presented in Part I. Serious discrepancies in high pressure gas viscosity data in the literature are discussed. The application of the correlation to predict absolute viscosities is discussed in Part 11. Auxiliary correlations are presented to enable calculations of viscosities from a knowledge of the pressure, temperature, and gravity of the gas phase. INTRODUCTION A knowledge of the viscosity of hydrocarbon fluids is needed to study the dynamical or flow behavior of these mixtures through pipes, porous media, or more generally wherever transport of momentum occurs in fluid motion. Since flow is predominantly in the laminar region in petroleum reservoirs, the influence of fluid viscosity on this flow is especially important. As early as 1894, Onnes1 and Onnes and de Haas&apos; noted that the viscosities of homologs under corresponding states could be correlated. The theorem of corresponding states has been further developed and applied to the viscosity of pure, nonpolar gases under pressure by Comings, Mayland, and Egly.3 It was demonstrated that the viscosity ratio could be expressed rather closely as a function of reduced pressures and temperatures, 1.e.: µ/µ1 = f( TR2 PR) ........(1) temperature, absolute units where: TR =------------------------------ ------ critical temperature. absolute units _pressure, absolute units critical pressure, absolute units µ = viscosity of gas at reduced temperature TR and reduced pressure PR µ1 =. viscosity of gas at atmospheric pressure and at temperature TR Serious discrepancies in the viscosity of pure hydrocarbon gases at high pressures have been called to Our attention by Comings, and and Egly. They made a careful analysis of the following methods commonly used to measure gas viscosities: 1. Oscillating disc viscometer4,5 2. Rolling ball viscometer6,7 3. Capillary tube viscometer12 On the basis of their analysis of the problem and their experimental data on the viscosities of methane, ethylene, carbon dioxide, and propane, they preferentially selected data obtained by the capillary tube viscometer to develop their viscosity correlation. Since then a need has existed to verify the experimental technique of Comings, Mayland, and Egly for the determination of viscosities at high pressure; to extend the data to mixtures of hydrocarbons; and to extend the range of their correlation to include higher pressures. Using the correlation procedure of Comings, May-land, and Egly, the prediction of gas viscosities is resolved into the correlation of the effect of pressure, temperature, and composition on the viscosity of hydrocarbons and their mixtures and the prediction of viscosities of mixtures of hydrocarbons and other natural gas components at one atmosphere pressure.

Jan 1, 1955

[NORTH AMERICA UNITED STATES ALABAMA Birmingham CORD, Richard H DISMUKES, Edward B Citronelle PERRIN, Huey P Fairfield PAGEL, Herbert Ervin Huntsville ENG, Harvard KELLEY, Dean W WAGGONER, J B Mobile HORNER, William L PETROUTSON, Peter C Montgomery GAMBLE, Halbert R Redstone RAWLINGS, William E Tuscaloosa MASON, William L University CUDWORTH, James R JONES, Walter B]

Jan 1, 1961

By J. A. Herbst, R. Mackelprang, J. D. Miller

Droplet size distributions were determined by stabilizing in gelatin and measurement of the distributions by means of computerized image analysis Several variables that affect droplet sizes were studied and the resulting size distributions were modeled via a population balance equation Key parameters in the model were related to the physical properties and operating conditions of the systems examined using a multiple linear approach

Jan 1, 1981