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GWILLIAM H. CLAMER* (Philadelphia, Pa.).-Sulphur is not so detrimental in its effect if oxygen is also present, so that in sulphur-carrying bronzes and brasses, it is advantageous to maintain a certain percentage of oxygen. As a matter of fact, it would be possible sometimes to correct difficulties by actually adding oxygen. If the cathodes were charged directly into an electric furnace in a neutral or reducing atmosphere, a very high grade of copper would result by a simple melting operation. This would very largely eliminate the loss occasioned by melting in a reverberatory furnace. In such a furnace a large amount of slag is produced during the oxidizing stage of refining. Notwithstanding the fact that melting in an electric furnace might be somewhat more expensive than melting in a fuel furnace, the ultimate result would be a saving and the production of a very high grade of copper.

Jan 1, 1919

By W. W. Mason

The US began exporting coal in the late 1800s, at first in very small quantities to Canada and, beginning in 1897 and 1898, to the east coast of South America. Shipments to European countries began on a very limited basis in 1902 and these shipments increased gradually until World War I when shipments overseas increased from 7.3 Mt/a to 20 Mt/a. After the war exports dropped as fast as they had increased and, with the exception of exports to Canada, remained at very low levels until just after World War II when the US again emerged as a major coal exporter. World War II left the coal industries of Europe in ruin. As the US was the only country able to supply large quantities of coal at reasonable prices needed for reconstruction of the European economy, the US coal exports overseas expanded rapidly to 38.6 Mt in 1947. Additionally, we shipped 23.8 Mt of coal to Canada in that year for a total export of 62.3 Mt. Unfortunately, that level was not reached again until 1957 when exports reached an all-time high of 69.3 Mt - a high that has not been reached since. Over the years the level of US coal exports has fluctuated fairly widely. Approximately 80-90% of all US coal exports are high quality metallurgical grade coal so our exports level depends directly on world-wide economic conditions and world steel production levels.

Jan 1, 1982

By Robert H. Chapman

During the past two years the writer has been traveling in the Lewis and Clarke timber reserve, locating the boundaries and reference-monuments for the Geological Survey. The Lewis and Clarke reserve lies in northwestern Montana. The region is very mouutainous, the main range of the Rocky mountains passing through it, dividing the waters of the Columbia and Missouri rivers. The mountains do not rise in one important and well-defined backbone, but in a series of parallel ridges, striking nearly northwest and southeast. Between these ridges, and, in general, parallel to them, are the drainage-systems. Beginning at the west, the rivers are the Swan, emptying into the Flathead lake, the South fork and the Middle fork of Flathead river, both emptying into the main Flathead river, which, in turn, empties into the lake of that name. The continental divide passes through the reserve from the southeast corner to the middle of the northern boundary, and the stream of most importance east of it is the Sun river, which heads well toward the north, and flows southeasterly and then eastward, and, emerging from the mountains, flows across the great plain of' the Missouri river. The southern boundary is drained by the Big Blackfoot river, flowing westward; the northern boundary, by the several branches of the Flathead river. The accompanying map (which is only a sketch, and does not represent the final work of the Geological Survey in this forest-reserve) shows clearly the parallel systems of drainage and ridges. The westernmost mountain range, the Mission, divides the great valley of the Flathead from the Swan river valley. The

Jan 1, 1900

By S. Mellgren, W. Opie

AN equilibrium state of importance in the process of electrolytically depositing titanium from fused chloride electrolytes is that which exists between titanium metal, titanium dichloride, and titanium trichloride. This can be expressed by the reaction titanium concentration of the solution, temperature, and the proportion of strontium chloride and sodium chloride in the solution. Procedure The general procedure used consisted of the following steps: 1) Development of an analytical method for determining Ti+2 and total titanium. 2) Preparation of batches of fused salt solutions containing various amounts of total titanium, Ti+2 and Ti+3 3) Blending of the prepared batches and excess titanium metal in Vycor tubes and allowing the solutions to come to equilibrium. By blending, solutions with different total titanium content could be prepared and equilibrium could be approached from the high Ti+2 and low Ti+2 sides. 4) Studying the effect of titanium concentration, temperature, and the mole ratio of the solvent chlorides, SrC1, and NaC1, upon the equilibrium.

Jan 1, 1958

By Gary E. McIntosh

This paper will discuss a US Bureau of Mines project designed to assess and predict the impacts which surface coal mining will have on the regional shallow groundwater systems in the Powder River Basin. The primary objective will be met through the accomplishment of the following: (1) The design and establishment of a regional network for monitoring shallow groundwater systems in the basin; (2) monitoring the direction and rate of flow, water quality, and aquifer characteristics of the shallow groundwater systems; and (3) development of a regional groundwater simulation model, with appurtenant subroutines to determine local effects.

Jan 1, 1980

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Jan 1, 1942

By E. T. Turkdogan, Klaus Schwerdtfeger, P. Grieveson

The rate of growth of "Fe4N" on a iron was measured by nitriding purified iron strips in flowing am -monia -hydrogen gas mixtures at 504" and 554°C. It is shown that a dense nitride layer is formed when a zone -refined iron is used in the experiments. With less pure iron, the nitride layer is found to be porous. Through theoretical treatment, the self-diffusivity of nitrogen is evaluated porn the parabolic rate constant, and found to be essentially independent of nitrogen actirlity, e.g., D* = 3.2 x l0-12 and 7.9x l0-12 sq cm per sec at 504" and 554?C. Some consideration is given to the mechanism of diffusion in the nitride phase. THERE is a great deal of background knowledge on the solubility and diffusivity of nitrogen in iron, and on the thermodynamics and crystallography of several phases in the Fe-N system. Although case-nitrided steels have many applications in practice, no work seems to have been done on the diffusivity of nitrogen in the iron nitride, ?', phase. The only work reported on the related subject of which the authors are aware is an investigation by Prenosil,1 who measured the growth rate of the e phase on iron by nitriding in ammonia-hydrogen gas mixtures. EXPERIMENTS Purified iron plates of approximate dimensions 1 by 0.5 by 0.03 cm were nitrided in flowing mixtures of ammonia and hydrogen, in a vertical furnace fitted with a gas-tight recrystallized alumina tube. After a specified time of reaction, the sample was cooled to room temperature by withdrawal to the water cooled top of the reaction tube. The furnace temperature was controlled electronically in the usual manner within *l°C; the temperature was measured using a calibrated Pt/Pt-10 pct Rh thermocouple. For each experiment the iron strip sample was cleaned with fine emery cloth and degreased with tri-chloroethylene prior to the experiment. The ammonia-hydrogen gas mixtures were prepared from anhydrous ammonia and purified hydrogen using constant pressure-head capillary flowmeters. The gas mixture flowed upward in the furnace with flow rate of 400 cc per min at stp. The composition of the gas mixture was checked by chemical analysis at regular intervals. In most cases, the compositions of the exit gas and metered input gas agreed within about 0.3 pct, indicating that cracking of ammonia did not pose a problem at the temperatures employed. Two series of experiments were carried out using two different types of purified iron samples. In the first series of experiments at 550°C, vacuum carbon deoxidized "Plastiron" was used. The main impurities present in this iron were, in ppm: 4043, 50-Cr, 20-Zr, 40-Mn, 20-P, 20-S, 20-C, 50-0, and 10-N. In these experiments the rate data were obtained by measuring the change in weight of the iron specimen suspended in the hot zone of the furnace by a platinum wire from a silica spring balance. The nitride layer formed in these experiments was found to be porous, particularly near the outer surface. In other experiments, high purity zone-refined iron (prepared in this laboratory) was used. The total impurity content of this iron was 30 ppm of which 20 ppm was Co + Ni, 4 ppm 0, other metallic impurities were less than 1 ppm. The zone-refined iron bar, -2.5 cm diam, was cold rolled to a thickness of about 0.03 cm and the specimens were prepared for the experiment as described earlier. After the nitriding experiment, the sample was copper plated electro-lytically and mounted in plastic for metallographic polishing. After polishing, the thickness of the ?' layer was measured using a metallographic microscope. The nitride layer formed on the zone-refined iron was essentially free of pores. RESULTS The different morphology of the nitride layers grown on "Plastiron" and zone-refined iron is shown in Fig. 1. Both samples were nitrided side by side for 55 hr. The holes in the less pure iron, Fig. l(a), are confined to a region about one half thickness from the outer surface. The dense layer grown on zone-refined iron, Fig. l(b), is thinner than the porous layer on the "Plastiron". The impurities in the iron are believed to be responsible for the formation of a porous nitride layer. The pore formation may be due to the high nitrogen pressures existing within the nitride layer, e.g., the equilibrium nitrogen pressure is 1.2 x l05 atm in the 38.6 pct NH3-61.4 pct H2 and 6.6 x l03 atm at the Fe-Fe4N interface at 554°C and 0.96 atm. It is possible that the oxide inclusions present in the electrolytic iron may facilitate the nuclea-tion of nitrogen gas bubbles within the nitride layer. Support for this reasoning is the fact that pores are only encountered in the outer range of the layer where nitrogen pressures are largest. The photomicrographs in Fig. 2 show the effect of reaction time on the thickness of the dense nitride layer formed on zone-refined iron. These sections are from samples nitrided in a stream of 29 pct NH3-71 pct H2 mixture at 554°C for 22, 70, and 255 hr. In all the sections examined the nitride-iron interface was noted to be rugged. These irregularities are be-

Jan 1, 1970

By D. K. Das, P. A. Beck, S. P. Rideout

IN a previous publication1 1200°C isothermal phase diagram sections were given for the Cr-CO-Ni, Cr-Co-Fe, Cr-Co-Mo, and Cr-Ni-Mo ternary systems, in which the a phase formed narrow, elongated solid solution fields. The present investigation is concerned with the 1200°C isothermal sections of the Co-Ni-Mo, Co-Fe-Mo, and Ni-Fe-Mo ternary systems. A prominent feature of these systems is the presence of narrow, elongated µ phase fields. The crystal structure of the phase designated as µ both here and in the previous publication1 was determined by Arnfelt and Westgren.2 For the (CO, W)µ phase, named by them Co,W, (and also frequently designated as a), these authors found that the crystal system is hexagonal-rhombohedra1 and the space group is D53d — R3,. Westgren and Mag-neli3 later found that isomorphous phases exist in the Fe-W and the Fe-Mo systems (these phases are often referred to as < and E, respectively). Henglein and Kohsok4 stated that the phase described by them as Co7Mo,; (otherwise frequently designated as c) is also isomorphous with the above three. The Co-Fe-Mo system was investigated at 1300°C by Koester and Tonn,5 who found a continuous series of solid solutions between (Co, MO)µ and (Fe, MO)µ Koester6 also indicated similar uninterrupted solid solutions in the Ni-Fe-Mo system. However, since the Ni-Mo binary system does not have a phase isomorphous with F, Koester&apos;s diagram is expected to be erroneous. No data appear to be available in the literature concerning the Co-Ni-Mo system. The face-centered cubic (austenitic) solid solut,ions of iron, nickel, and cobalt, which are quite extensive in all three systems at 1200°C, are here designated as the a phase. The body-centered cubic (ferritic) solid solutions, based on iron, are designated in this report as the ? phase, in conformity with the nomenclature used previously.&apos; Experimental Procedure The alloys were prepared by vacuum induction melting in zirconia and alumina crucibles. The lot analyses for the metals used have been given.&apos; The number of alloys prepared was 46 for the Co-Ni-Mo system, 65 for the Co-Fe-Mo system, and 113 for the Ni-Fe-Mo system. The compositions of these alloys were selected with due regard to maximum usefulness in locating phase boundaries. The alloy specimens were annealed at 1200°C in an atmosphere of purified 92 pct helium and 8 pct hydrogen mixture. Alloys consisting almost entirely of the face-centered cubic austenitic a phase, or of the body-centered cubic ferritic c phase were double-forged with intermediate annealing. The double-forged specimens were then final annealed for 90 hr at 1200 °C and quenched in cold water. Alloys containing considerable amounts of any of the other phases could not be forged. Such specimens were annealed for 150 hr at 1200°C and quenched. Microscopic specimens of all alloys were prepared by mechanical polishing, in many cases followed by electrolytic polishing. Description of the polishing and etching procedures used and tabulation of the intended compositions of the alloys prepared are being published in two N.A.C.A. Technical Notes.7,8 , Many of the alloys were analyzed chemically and, in general, the results are in excellent agreement with the intended compositions. X-ray diffraction samples were prepared by filing or crushing homogenized alloy specimens and by reannealing the obtained powders in evacuated and sealed quartz tubes. After annealing for 30 min at 1200°C the tubes were quenched into cold water. X-ray diffraction patterns were made with unfiltered chromium radiation at 30 kv, using an asymmetrical focusing camera of high dispersion. X-ray diffraction and microscopic methods were used jointly to identify the phases present in each specimen. The amounts of the phases in each alloy were estimated microscopically. The phase boundaries were located by the disappearing phase method. The results were used to construct 1200°C isothermal sections for the three ternary phase diagrams. The accuracy of the location of the phase boundaries determined in this manner is estimated to approximately ±1 pct of each component. The portion of the three phase diagrams lying between the µ, P, and 6 phases on the one hand, and the molybdenum corner on the other, has not been investigated. Recently Metcalfe reported0 a high temperature allotropic form of cobalt on the basis of dilatometric results and of cooling curves. In the present work no attempt was made to search for the new phase in the cobalt corner of the Co-Fe-Mo and Co-Ni-Mo systems. No alloy was prepared with more than 80 pct Co; the alloys used were intended to locate the boundary of the a phase saturated with cL. The microstructures of the quenched a alloys near the cobalt COrner gave no suggestion of an in-suppressible transformation On quenching. The location of the boundaries of the a + ? two-phase fields in the Fe-Ni-Mo and Fe-CO-MO systems was determined entirely by the microscopic method. The face-centered cubic a alloys near the ? field transform partially or wholly into the body-centered cubic ? phase on quenching from 1200°C to room temperature. The ? formed in this manner has an

Jan 1, 1953

By LeRoy Scharon

EACH year it becomes apparent that geophysical activities in the fields of mining and engineering are increasing in the number and variety of applications. Many mining companies are including, as part of their exploration programs, geophysical surveys. The value of geophysics in highway and structural foundation investigations has been realized and is now an important part of subsurface investigations in conjunction with soil and rock borings. United States of America One of the major orebody discoveries of the year is that of the Grace mine near Morgantown in Berks County, Pa. This orebody, now under development by the Bethlehem Steel Co., was discovered by an airborne magnetometer survey carried out by the Aero Service Corp. of Philadelphia. The orebody, the geological occurrence of which is similar to those existing at Cornwall, Pa., was found at a depth of 1500 ft under a cover of Triassic sediments and is reported to have a reserve of well over 100 million tons. Shaft sinking and other construction work has started at the site. Resistivity work was carried out at proposed dam sites in New York and in connection with the search for fluorspar veins in Kentucky. Spontaneous polarization investigations were pursued in the Appalachian region at various localities from North Caro¬lina up into Virginia. This work was done in connection with the search for sulphide-bearing structures. Several indications were proven by subsequent drilling to correspond to unknown sulphide deposits, a few of these occurring in the vicinity of properties long under exploitation. Refraction seismic methods applied to bedrock depth determinations as related to water problems on the Marquette Range and the extension of the. regional gravity survey on the Menominee Range to learn the major structural features of the area have been reported by, Lloyal O. Bacon. A gravity survey has been completed in the vicinity of Tioga, Bradford County, Pa. with a gravity profile being observed from Tioga east to the Delaware basin. The Indiana Geological Survey is concerned with a state-wide gravity survey. Judson Mead, University of Indiana, reports that the bulk of the State Survey&apos;s geophysical work, however, has been "seismic refraction work in connection with drift thickness problems. The survey has made almost 1000 determinations in areas of moderately thick drift. The results of this work are of interest to both the coal mining industry and to the stone industry." In the southeastern Missouri lead belt, magnetic electrical resistivity, and electromagnetic applications for the discovery of new lead deposits have been used with success. A gravity survey of the residual-barite deposits in Washington County, Mo., was made during the summer season with preliminary computations of tonnages checking with tonnages mined. Robert M. Dryer, of the University of Kansas has had considerable success in mapping structural features in southwestern Kansas with the gravity meter and is now engaged in tracing shoestring sands in eastern Kansas by resistivity surveys. Several, foundation sites were investigated in greater St. Louis using electrical resistivity and seismic refraction methods with success. A minimum amount of drilling data was available for checking and interpreting the geophysical results (Fig. 1). It is to be noted that geophysical methods are finding a place in subsurface investigations for highway and foundation problems. Interest has been so keen in this field that the American Society for Testing Materials, at its annual meeting in June of this year, devoted one session of its symposium on surface and subsurface reconnaissance to geophysical papers involving the application of the electrical resistivity and seismic refraction methods to subsurface studies. At least three major mining companies in the United States have entered the field recently in geochemistry. The program of research and development of geochemical techniques by the U. S. Geological Survey continues. Experimental field projects were conducted over lead-silver, cobalt, copper and zinc deposits in Idaho, Oregon, California, Wisconsin and Montana. Similar experiments were carried on by M. P. Nackowski in the Illinois-Kentucky fluorspar district and in the Tri-State Zinc district by R. Maurice Tripp with favorable results. Geophysical activities of the U. S. Geological Survey for 1951 were extensive and varied. About 21,000 miles of airborne magnetic and 10,000 miles of airborne radioactivity traverse were flown in 1951 by the U. S. Geological Survey. A total of 35,000 miles of aeromagnetic traverse were compiled, 57 aeromagnetic maps were published and 14 preliminary maps were placed on open file. Airborne surveys were made in Aroostook County, in the Katahdin and Dead River areas in Maine; in northwest Washington; over the Mother Lode district in California; in northeastern and northwestern Minnesota; and in the New York-New Jersey highlands. Of special interest were the surveys in Washington, where highly magnetic Eocene lavas gave information on structures in the overlying Miocene sedimentary rocks and in northeastern Minnesota over the Duluth gabbro. The latter survey was made following the discovery of nickel-copper mineralization in the gabbro near its contact with the Virginia slate. The principal ground geophysical surveys for metalliferous deposits and related purposes were made in the Colorado Plateau region, where electrical surveys assisted in prospecting; in Aroostook County, Maine, where ground magnetic surveys, following aeromagnetic surveys, have permitted tracing

Jan 1, 1952

By R. L. Boyer, F. Morgan, M. Muskat

In the last several years a type of application of the fundamental permeability-saturation relationships has been developed which offers great promise in the interpretation of general reservoir performance.l-&apos; In these developments no attempt is made to solve the detailed flow dynamics in actual oil and gas-producing systems. That problem still remains unsolved. But the permeability-saturation phenomena are incorporated in the analysis of oil-producing reservoirs in a manner such as to reflect the true role they play in controlling the gross reservoir behavior. In particular, they are introduced in such a manner as to determine the gas-oil ratio of the production at any stage of depletion, and, when combined explicitly with the so-called material-balance principles in differential form, one can obtain a differential equation describing completely the average pressure and gas-oil-ratio history of oil-producing reservoirs. While thus far they have been applied directly only to gas-drive reservoirs, they are susceptible of extension to partial water-drive systems, and qualitatively the same principles are of value in the study Of complete water-drive reservoirs. Moreover, in addition to giving a means for computing the variation of the reservoir pressure and gas-oil ratios vs. the cumulative production, they automatically lead to predictions of the gross ultimate recovery under natural depletion—and when properly extended they provide means for predicting the ultimate recovery under gas or water injection. The data required for such applications are the initial fluid distribution in the producing section, the pressure-volume-temperature data on the gas and liquid phases, and the permeability-saturation relationship for the oil-satuiated zone. The former can be obtained with reasonable accuracy by methods that are well established and available throughout the industry. The permeability-saturation data, however, involve techniques that are not at all standardized. In fact, only

Jan 1, 1947

By M. Muskat, R. L. Boyer, F. Morgan

In the last several years a type of application of the fundamental permeability-saturation relationships has been developed which offers great promise in the interpretation of general reservoir performance.l-&apos; In these developments no attempt is made to solve the detailed flow dynamics in actual oil and gas-producing systems. That problem still remains unsolved. But the permeability-saturation phenomena are incorporated in the analysis of oil-producing reservoirs in a manner such as to reflect the true role they play in controlling the gross reservoir behavior. In particular, they are introduced in such a manner as to determine the gas-oil ratio of the production at any stage of depletion, and, when combined explicitly with the so-called material-balance principles in differential form, one can obtain a differential equation describing completely the average pressure and gas-oil-ratio history of oil-producing reservoirs. While thus far they have been applied directly only to gas-drive reservoirs, they are susceptible of extension to partial water-drive systems, and qualitatively the same principles are of value in the study Of complete water-drive reservoirs. Moreover, in addition to giving a means for computing the variation of the reservoir pressure and gas-oil ratios vs. the cumulative production, they automatically lead to predictions of the gross ultimate recovery under natural depletion—and when properly extended they provide means for predicting the ultimate recovery under gas or water injection. The data required for such applications are the initial fluid distribution in the producing section, the pressure-volume-temperature data on the gas and liquid phases, and the permeability-saturation relationship for the oil-satuiated zone. The former can be obtained with reasonable accuracy by methods that are well established and available throughout the industry. The permeability-saturation data, however, involve techniques that are not at all standardized. In fact, only

Jan 1, 1947

By J. W. Halley, G. L. Plimpton

Because of the two distinct stages in the solidification of rimmed steel, segregation in the rimmed ingot is more complex than that in the killed or semikilled ingot. In the earlier stage, chemical reactions, resulting in evolution of gas and vigorous stirring of the metal, effect a degree of negative segregation unique to rimmed steel. The composition of this zone constitutes the principal quality advantage of this type of steel. In the later stage of solidification, after the evolution of gas has ceased, the segregation follows the general pattern of a more completely deoxidized steel. However, the composition of the liquid remaining after the first solidification stage varies markedly from that of the original melt, some constituents having been partially removed as reaction products while the concentration of others has been intensified by rejection from the metal solidifying in the first zone. The aim, from the standpoint of segregation, in rimmed steel of high quality is to effect a maximum negative segregation in the rim zone without excessive concentration of undesirable elements at the center of the ingot. To achieve this aim, the composition of the melt may be varied and the furnace and pouring practice may be adjusted within certain limits. It is the purpose of this study to discuss segregation in rimmed steel from the standpoint of the mechanisms that produce it and to survey the phases of open-hearth practice that influence those mechanisms. Mechanisms Producing Segregation The mechanisms that determine the degree of segregation in the rimmed ingot are closely interrelated, making it difficult to select the primary factors and to determine a satisfactory order for presenting them. For instance, the question of sulphur segregation is relatively simple, since sulphur is not directly involved in chemical reactions in the ingot; but its concentration in the rim zone is dependent not only on its original analysis in the melt, its segregation coefficient, and the freezing rate, but also on the rate of its removal from the impure film on the solidifying surface. This washing action involves all the factors (such as freezing rate, the carbon-oxygen product, pressure, etc.) that determine the rate of gas evolution and hence the efficiency of film removal. Sulphur distribution between the rim and core is affected by the volumetric ratio between the two zones, and its segregation in the core is a function not only of the freezing rate of the core but also of all the foregoing factors that determine its concentration in the metal when solidification of the core starts. To simplify the presentation, it is proposed to treat the mechanisms affecting segregation independently in this section, reserving a discussion of their over-all effects for the section in which actual segregation data are given. The factors affecting segregation will be treated in the following order: (I) differential solidification, (2) removal of constituents as

Jan 1, 1945

By Sylvan Cromer

The need for a clear understanding of the physical nature of the flow of gas-liquid mixtures in vertical pipes is ever becoming more apparent. This type of flow is encountered when gas and oil are produced from a well; when water is removed from gas wells with siphon lines and when liquids are elevated by means of air or gas lift. Although a number of investigator1-7 have published data on the flow of gas-liquid mixtures, in only a few cases has the experimental setup been devised to permit visual study. In the fields of heat transmission, such as the boiling of liquids and the study of the critical phenomena of the hydrocarbons, researchers have been able to throw additional light on heretofore unexplainable happenings through actual observation in glass apparatus. This investigation was therefore undertaken in order to obtain qualitative as well as quantitative results for air-water flow. Experimental Apparatus and Procedure The flow column used in these tests was made of standard 2-in. pipe and was approximately 98 ft. in height. Pyrex observation sections 2 ft. long having the same internal diameter as the wrought-iron pipe were placed at 14-ft. intervals in the column. The bottom of the tube was cut off square and terminated in the mixing chamber. No perforated nipple or footpiece of any kind was used. To the top of the column was fastened a semicircular return bend having a 4-ft. radius. The flow column was supported by a standard cable-tool drilling derrick (Fig. 1) into which were built observation platforms at each Pyrex section.

Jan 1, 1940

By Sylvan Cromer

The need for a clear understanding of the physical nature of the flow of gas-liquid mixtures in vertical pipes is ever becoming more apparent. This type of flow is encountered when gas and oil are produced from a well; when water is removed from gas wells with siphon lines and when liquids are elevated by means of air or gas lift. Although a number of investigator1-7 have published data on the flow of gas-liquid mixtures, in only a few cases has the experimental setup been devised to permit visual study. In the fields of heat transmission, such as the boiling of liquids and the study of the critical phenomena of the hydrocarbons, researchers have been able to throw additional light on heretofore unexplainable happenings through actual observation in glass apparatus. This investigation was therefore undertaken in order to obtain qualitative as well as quantitative results for air-water flow. Experimental Apparatus and Procedure The flow column used in these tests was made of standard 2-in. pipe and was approximately 98 ft. in height. Pyrex observation sections 2 ft. long having the same internal diameter as the wrought-iron pipe were placed at 14-ft. intervals in the column. The bottom of the tube was cut off square and terminated in the mixing chamber. No perforated nipple or footpiece of any kind was used. To the top of the column was fastened a semicircular return bend having a 4-ft. radius. The flow column was supported by a standard cable-tool drilling derrick (Fig. 1) into which were built observation platforms at each Pyrex section.

Jan 1, 1940

By G. W. Binkley, R. E. Collins, G. K. Dumbauld

A mathematical analysis has shown that the primary factors affecting the deposition of cement in unfractured perforations during squeeze-cementing operations are: the properties of the cement slurry, the geometry of the perforations, and the filtration time. The validity of the analysis has been substantiated by laboratory investigations. The information presented in this paper makes possible the prediction of the rate of deposition of cement in and about unfractured perforations under given squeeze-cementing conditions, the proper filtration time to control the amount of deposition to any desired value, and the deposition properties needed in cement slurries to restrict to any desired degree the formation of nodes of cement .Solids inside the casing. INTRODUCTION The deposition of solids against a permeable medium by the process of filtration is an important property of a cement slurry. General recognition of the role of filtration in the use of cement in wells is evident in view of the fact that several patents on low-water-loss cements have been issued during the past few years. In the conventional, high-pressure squeeze-cementing technique, a large volume of cement slurry is usually displaced into the area surrounding the perforated interval after the formation has been fractured hydraulically.&apos; Near the end of the job, the pumping rate is slowed or stopped intermittently in an effort to obtain a high pressure in the wellbore. The way in which a high pressure is obtained is not understood thoroughly. but it is be- lieved to be caused by the deposition of a rigid mass of compacted cement particles either in the fractures of the formations or inside the casing opposite the perforated interval. In a method of squeeze-cementing introduced several years ago, a small amount of cement slurry is squeezed into the perforations at a low pressure to avoid fracturing the formation. The filling of the unfractured perforations with cement particles by the process of filtration is important to the success of this technique. Early in the development of this low-pressure squeeze-cementing technique, laboratory and field-size experiments showed that conventional, neat cement slurries were unsatisfactory if the tubing was extended into or through the perforated section of the casing. The extremely high filtration rate of neat cement slurries caused the deposition of a compacted mass of cement inside the casing and made it impossible to remove excess cement by reverse circulation and difficult to withdraw the tubing. Because the need for cements with a reduced filtration rate was obvioils and urgent, modified cements containing 12 per cent bentonite were used until research was completed on modified cements containing 25 per cent bentonite.< These modified cements were useful in the solution of the immediate problem, but the following questions remained unanswered: (I) what is the optimum filtration rate of cement slurries for this application, (2) how long should the squeeze pressure be applied. and (3) how great are the effects of squeeze pressure and well temperature on the rate of deposition? Furthermore, the relationship of the filtration properties of cement slurries to the dimensions of the perforations and the wellbore was unknown. In order to obtain information relative to these basic considerations, a systematic evaluation of all the factors involved in the deposition of Cement during low-pressure squeeze-cementing operations was initiated. Although the work was directed toward an evaluation of the factors influencing the deposition of Cement in the low-pressure squeeze-

By L. D. Fetterolf, G. T. Mahler, W. M. Peirce, R. K. Waring

Until recently, the only commercial method of producing magnesium has been fused salt electrolysis, despite a considerable amount of experimental work on the direct reduction of magnesium oxide. In this early work, a number of investigators demonstrated that magnesium oxide would react with any one of several reducing agents to produce magnesium vapor, but that the mixture of magnesium oxide and reducing agent must be heated to a high temperature even in a vacuum. In particular, it was demonstrated that silicon and aluminum are effective reducing agents and that when either of these is used the magnesium vapor can be condensed to massive metal. In spite of this knowledge, no successful commercial reduction process was developed, at least in this country, because of the operational difficulties imposed by the requirement of high temperature and vacuum and because of the high cost of the reducing agent. The outstanding experimental work done by Pidgeon, who carefully reviewed all of the known methods of making magnesium and then selected ferrosilicon reduction, overcame some of the operational difficulties. The process developed by Pidgeon comprises briquetting a mixture of calcined dolomite and reducing agent, preheating the briquets to about 600°C. in an externally heated alloy retort, reducing the MgO with silicon in an evacuated horizontal alloy retort heated externally to about II50 C., and condensing the magnesium vapor to a solid in a cold extension of the retort projecting beyond the front of the furnace. A major advantage of Pidgeon&apos;s process is that the retort is not cooled down between charges. Earlier investigators had used apparatus that necessitated cooling and reheating of the retort between charges. Early in January 1942, when the War Production Board was considering the Pidgeon process for quickly increasing the production of magnesium, The New Jersey Zinc Co. offered to have a research investigation of the process carried on, with the hope of assisting in its further development. This offer was accepted, and a two-retort pilot plant was built at Palmerton and put in operation on Jan. 29,1942. An intensive investigation of certain phases of the process was carried out in the ensuing four months. This investigation was completed in the last part of May 1942) and the pilot plant was then shut down. Subsequently, The New Jersey Zinc Co. was requested to have further development work done on the process, and a more extensive investigation was undertaken in August 1942 under contract with the War Production Board and under the supervision of the War Metallurgy Committee. This paper describes the ,phases of the investigation that are thought to be of sufficient general interest to merit publication.

Jan 1, 1944

By John Wulff, David A. Stevenson

The solubility of iron and cobalt in liquid lead, the solubility of chromium in liquid tin, and nickel in liquid silver were determined up to 1300°C in an atmosphere of hydrogen. Liquid samples were taken at different temperatures and analyzed. The data obtained were plotted to show the relationship between log mole fraction of solute and the inverse of the absolute temperature. Resulting values for the differential heat of solution (AH) and the excesspartial molar entropy (S)are: for the iron-lead system = _24,200 cal per mole and AT = 5.0 e.u. for the a phase, and AH = 18,300 and S = -0.1 e.u. for the y phase; for the cobalt-lead system AH = 16,500 cal per mole and AS =0.7 e.u.; for the chromium-tin system AH = 15,600 cal per mole and AS = 8.5 e.u.; for the nickel-silver system AH =18,000 cal per mole and AS = 4.0 e.u. RECENT developments in coating, brazing, and heat transfer have focused attention on specific cases of solid-liquid interaction in metal systems, particularly those involving dilute liquid solutions. One fundamental quantity of interest in such systems is the equilibrium phase distribution between solid and liquid phases. In any effort to fully understand such interactions, one must be able to describe the equilibrium state precisely. Furthermore, in order to develop genera! relations for such systems, one must know the equilibrium state in a number of different cases. This investigation was devoted to a study of the equilibrium phase distribution in four binary systems: solid iron-liquid lead; solid cobalt-liquid lead; solid chromium-liquid tin; solid nickel-liquid silver. The iron-lead system was previously studied by Shepard and parkman&apos; and later by Fleischer and Elliott2 with differing results. Both investigations were carried out by sampling the saturated liquid, and analyzing it chemically. The cobalt-lead system was previously reported by Pelzel,3 who noticed no discontinuity near the transformation. A limited investigation of the chromium-tin system was made by Wlodek and wulff4 using a weight loss method. This work was done in conjunction with the development of a process for coating molybdenum with chromium from tin solutions. To more fully under- stand the kinetics of the process, a more accurate determination of a solubility was desirable. No significant data were found in the literature on the nickel-silver system. Data on the latter system were, however, relevant to the investigation of the corrosion kinetics of copper-nickel alloys in liquid silver as carried out by Harrison and wagner,5 EXPERIMENTAL APPARATUS AND PROCEDURE Of the techniques available for the study of such systems the most effective appears to be that of liquid sampling,2,6,7 which is the method used in the present investigation. A schematic diagram of the sampling furnace is given in Fig. 1. Large pieces of solute metal, in excess of saturation solubility, were added to 200 g of the solvent metal, and the entire charge placed in an alundum crucible. Analytical reagent or materials of chemically pure grade were used in all investigations. The crucible was contained in a zircon muffle tube positioned vertically in the uniform hot zone of a Globar resistance furnace. The tube was provided with a number of ports which permitted sampling at temperature and in controlled atmospheres or vacuum; the ports were also useful for evacuation and introduction of gases as well as for thermocouple measurements. A chromel-alumel thermocouple Sheated in a porcelain tube was used for temperature measurements. A purified hydrogen atmosphere was employed in all experiments reported in this paper. The hydrogen was purified by passing it first over hot copper gauze to remove oxygen and then through a molecular sieve immersed in

Jan 1, 1962

By J. W. Mitchell

Season cracking of 70-30 cartridge brass cases of small arms and artillery ammunition has been under investigation at the Frankford Arsenal for many years. The nature of this stress-corrosion failure has been found to be intergranular. Much of this work, however, has been directed toward improvements in method of manufacturing the cases so as to reduce the tendency to season crack and little progress had been made toward finding the source of the chemical agent producing the inter- granular corrosion. Ammonia has been shown to produce season cracking in brass and is known to be present in certain atmospheres, particularly industrial, in sufficient concentration to cause cracking. However, in the case of small arms ammunition, the hypothesis that atmospheric ammonia is the cause will not hold, since small arms ammunition is hermetically sealed during storage and yet occasional lots are found to have cracked after 3 to 5 yr. storage. Much of the early study of season cracking in small arms ammunition was done by Nicholas H. Murdza of the Frank- ford Arsenal. In 1936, he suggested that the corrosive agent might be one of the decomposition products of smokeless powder and mentioned nitrogen oxides specifically. Then in 1937, Murdza suggested that the breakdown of smokeless powder in storage resulted in the formation not only of nitrogen oxides but also ammonia

Jan 1, 1945

By D. Gupta, S. Weinig

This investigation comprises the study of dislocation-oxygen interactions in a! titanium and its effect on the ductile to brittle transition in titanium. Internal friction techniques using a low-frequency lorsion pendulum were used to study the oxygen atom interactions with dislocations in "superpurity" titanium. A calculation of the interaction energy between an oxygen atom and a dislocation, based on the "breakaway" strain resulted in a value of 0.015 ev as compared to theoretical values of 0.022 and 0.035 ev for edge and screw dislocations, respectively. Both the saturation of the room temperature decrement and the transition from ductile to brittle behavior occurred at 1.5 at. pct 0. It was proposed that the embrittlement was due to oxygen atoms immobilizing the dislocations. It was possible to increase the ductility of the Ti-0 binary alloys by decreasing the oxygen pinning. The increase in uniform elongation was 30 pct for an increase in the preanneal temperature of 300°C. ThE room-temperature ductility of a titanium is significantly affected by interstitial solutes. Although oxygen has a solid solubility of 15.5 pct by weight, the room-temperature ductility extends only to 0.6 pct.&apos; The ductility precipitously falls at this concentration and the fracture characteristics change from ductile to brittle.2 The small effective bulk composition of solute required to destroy the room-temperature ductility of the titanium must be indicative of an in-homogeneous distribution of solute atoms. Internal friction techniques were used in this investigation to

Jan 1, 1960

By Brison Robertson, W. P. Fishel

The carbide-forming tendencies of the various steel-alloying elements, or their affinities for carbon, is a subject that has received considerable attention, but little more than a probable arrangement of the elements as to their carbide-forming tendencies has been proposed. The physical properties of alloy steels depend upon the relative proportions of the elements present and their combinations. one important phase of this subject is the distribution of carbon between the various elements present. The distribution of car. bon between iron and other elements evidently sill depend upon: (I) the affinity of each for carbon; (2) the relative atomic masses of the elements present; and (3) the possible formation of compounds between the alloying and iron and between the elements themselves, In ternary steels the case is simplified, especially in systems in which the element and iron form no compounds, In such systems iron and the alloying element are competing for the carbon present. In this work the distribution of carbon between titanium and iron has been studied by measuring the relative amounts of iron carbide and titanium carbide present ill a series of annealed steels in which the ratio of titanium to carbon extended from 0.527 to 4.61. Ten Fe-Ti-C alloys, weighing about 250 grams each, were prepared by melting under a Vacuum, in an Induction furnace, Armco iron, carbon-free ferrotitanium (25 per cent Ti), and pure carbon. Vacuum melting prevented the formation of titanium oxides and nitrides, which would the the problem. The melts were made in graphite crucibles lined with sintered magnesium oxide. The ingots were the in the furnace under a vacuum and "&apos;ere then completely annealed at 950°C. The determination of the amount of titanium carbide present was based upon the established insolubility of titanium carbide in boiling dilute (1:4) sulphuric acid, and the complete solubility Of free titanium and titanium-iron compounds in this acid. High-carbon ferrotitanium, which had been treated to remove free Ti and Fe. was found to be completely insoluble in the acid; and the carbon-free ferrotitanium used in making the alloys was found to be completely soluble. Others have reported the insolubility of titanium carbide in sulphuric and hydrochloric acids. Turnings from the ingots were digested with boiling sulphuric acid (1:4) until all action had ceased. The carbide residue was filtered off and analyzed for titanium, and in some cases for carbon. This represerifs the titanium that was united with carbon The filtrate from the carbide residue contains the portion Of the titanium that was in solid solution in the ferrite. Titanium

Jan 1, 1945