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By Charles Dorrance

Culm is a general term used in the anthracite regions for many years to denote a mixture of coal, bony coal and impurities which is sent to the refuse-banks. Thus, 35 years ago culm contained the pea and buckwheat sizes of anthracite; but to-day, and as mentioned in this paper, culm is used specifically to denote the material which passes through the smallest screen in the anthracite-breaker. The smallest size of commercial anthracite is known as No. 3 buckwheat, barley, or bird's-eye coal, and is ordinarily made through a round-punched plate having openings & in. in diameter, and over a round-punched plate with openings 3/32 in. or 1/16 in. in diameter. Thus culm will consist of coal, bony coal, slate, gravel, iron pyrite, etc., ranging in size from 3/32 in. down to dust. Other local terms for culm are " slush," " silt," and " dirt." The first experiments towards the utilization of anthracite culm by briquetting, and the first briquetting-work done in this country, were in 1872 at Port Richmond Piers, Philadelphia, Pa., by E. F. Loiseau.1 Clay was used as a binder and the finished briquette was water-proofed with shellac, etc. Excessive cost was given as the reason for discontinuing work at this plant.

Jan 1, 1912

By Marcus Nadler

WAGES in the United States, in spite of the wage freeze, have increased materially. Overtime payments have become standard practice in almost all industries. Now efforts are being made to place wages on an annual basis, and if this is adopted, it will result in an increase in the cost of production. Organized labor today is more powerful than ever before; union membership is large and steadily increasing, and in many instances membership in the union is a prerequisite to employment. The treasuries of many unions are strong as a result of the large membership and full employment. The unions, therefore, today are in a much better position than ever before to carry on long strikes. Politically, too, the unions are more powerful today than they ever were. On the basis of their strength, one may expect that some of the demands that the labor unions will make in the not distant future will be granted. It is, therefore, quite evident that before long, particularly when the curtailment in war production reaches about 40 per cent, this country will be confronted with a serious labor problem.

Jan 1, 1945

By Robert F. Mehl

EXTENSION of physical and chemical methods of research in the study of metallic behavior continues rapidly, particularly in the correlation of behavior with crystal structure, and in the analysis of elastic and plastic properties. The growth of the science of metals during 1933 calls for special comment; the need for special reviews and for textbooks and monographs is now acute, as might he supposed from the number of references appended to this article, a list which is much abbreviated.

Jan 1, 1934

By D. W. White

The kinetics of isothermal transformation of ß-to-u uranium have been studied over a broad temperature range in alloys containing from 0.3 to 4.0 atomic pct Cr. Two modes of transformation are indicated by the existence of two C-curves in the TTT diagram. The upper temperature mode is regarded as a nucleation and growth mechanism, whose rate is controlled by diffusion of chromium in the ß phase matrix. The lower temperature mode is martensitic in nature. The M, temperature increases with decreasing chromium content, suggesting that the two transformation processes become synonymous in unalloyed uranium. URANIUM metal undergoes two allotropic transformations in the solid state. The a phase, orthorhombic in crystal structure,' is stable from room temperature up to about 665°C. The ß phase, characterized by a complex tetragonal structure,' prevails from 665" to about 770°C. The y phase is body-centered-cubic3 and is the stable modification from 770°C up to the melting point (about 1130"). In uranium of reasonable purity, neither of the two high temperature phases can be retained by quenching. However, the addition of certain alloying elements to uranium makes it possible to retain either the y-uranium phase or the ß-uranium phase at room temperature. Chromium alloyed in small amounts with uranium will permit retention of the ß-uranium phase in a metastable state at room temperature upon quenching from a ß-phase temperature.' From available information' on the equilibrium phase diagram for the U-Cr alloy system (Fig. I), it is to be expected that, however sluggish in its rate, the ß phase in such alloys should decompose eutectoidally to a phase and elemental chromium. It was the aim of this investigation to measure the rate and study the nature of this decomposition as a function of temperature and of chromium content. The investigation was reported in classified literature about five years ago and has recently been declassified for publication. In the meantime, there have appeared the papers of Holden,5 Mott and Haines,".' and Butcher and Rowe8 ealing with the metallography and the crystallography of the ß-to-a transformation in U-Cr alloys. These investigators have confirmed several of the phenomenological observations that will be described in the present paper and have examined in considerable detail certain aspects of the transformation and its mechanism. Although all of these investigations have concerned themselves experimentally with U-Cr alloys for the most part, an important consequence has been a clearer understanding of the nature of the ß-to-a transformation in uranium metal itself. Experimental Procedure This investigation dealt with a series of uranium alloys varying in chromium content from 0.3 to 4.0 atomic pct (0.066 to 0.90 weight pct). On five of the alloys, rates of isothermal transformation from the ß to the a phase were measured over a wide temperature range, leading to the development of TTT (time-temperature-transformation) diagrams. Transformation rates were measured over certain narrow temperature ranges on additional alloys. The alloys were prepared by vacuum melting and casting, using zircon or magnesia crucibles and graphite molds. Electrolytic chromium was used as the alloying addition, and the uranium was Mallin-ckrodt biscuit metal that had been vacuum remelted and cropped to remove many of the nonmetallic impurities that had floated to the top of the ingot. The ingots, 3/4 or 1 in. diam, were reduced in size by swaging. Alloys containing less than about 2 atomic pct Cr were swaged at 250° to 275°C, with initial and intermediate anneals at 550°C after every 75 pct reduction in area. Alloys with higher amounts of chromium were swaged at 550" to 600°C, although at the smaller sizes some of them were reduced by the procedure used on the more dilute alloys. Before use as test specimens, the swaged rods were annealed at 700" to 720°C for several hours, followed by slow furnace-cooling. The purpose of the anneal was to achieve the maximum amount of solution of the available chromium into the ß phase, as well as to remove extensive preferred orientation. The isothermal transformation rates were measured dilatometrically, using a quenching dilatometer and an experimental technique similar to those employed by Davenport and Bain in their original work on the transformation kinetics of austenite in

Jan 1, 1956

By J. A. Barr, R. B. Burt, I. S. Tillotson

DISCUSSION Howard Howie (Knoxville, Term.)—The authors are to be congratulated on the presentation of a paper containing so much valuable information on the pipeline transportation of phosphate, as there is very little literature on the subject. The writer is especially interested in the paper, as he conceived the arrangement of the Akin and Godwin plants and was in charge of the design work and the engineering incident to their construction. The Akin and other phosphate deposits in the Tennessee phosphate area lie on beds of limestone that are very irregular. The limestone beds, after the phosphate matrix has been removed, are similar in appearance to land severely eroded by the action of water and denuded of top soil. Depressions in the limestone, called cutters, are irregular in depth with vertical or overhanging walls, having the general appearance of cracks in dried clay. They change abruptly in direction, width, and depth, and vary on the Akin tract from 1 to 25 ft in depth and from 1 to 50 ft in width. Pinnacles of limestone commonly occur in the cutters which appear, when exposed, like small clifflike islands in a river. Limestone floats also occur. The phosphate matrix fills the cutters and covers the uncuttered areas, the thickness of the cover varying continually and sometimes rather abruptly. It occurs generally as stratifications of phosphate rock and clay of varying thickness. The phosphate rock in the matrix varies in hardness and in percents of silica, lime, iron oxides, and fluorine, and the clay varies in toughness. In some places the deposit consists of narrow strata of rock almost devoid of clay streaks. In other nearby locations the clay will predominate. When it is excavated, the phosphate rock breaks into thin irregular lumps, locally known as plate rock. Limestone lumps are also excavated with the matrix. Akin plate rock is generally much softer than that occurring in other deposits in the area. Because of the above described physical and chemical variations of the excavated material, the resultant slurry varies in size distribution, specific gravity, and percent of slimes. When the rock is soft or when there is an increase of clay, the slime fraction is greatly increased as it passes through pumps and pipelines, resulting in reduced pipe friction. It is obvious that the longer the pipeline the greater the reduction of coarse fractions into fines, causing a decrease in pipe friction that cannot be accurately evaluated. The matrix is mined with a dragline that drops it into a hopper with a grid composed of 9-in. parallel bar spacings located above the hammer mill. The matrix on, and passing through the grid, is subject to the action of powerful sprays which wash it down to the hammer mill, together with any limestone lumps that are not removed before passing through the grid. The hammer mill reduces the feed to lumps of plate rock and clay, most of which will pass through the 8-in. pump suction. The mixture discharges into a pool containing the pump suction pipe. Water from a hydraulic nozzle moves the mixture to the pump suction intake. The pump, driven by a variable speed motor, is the same size as the pumps mentioned on p. 279. Provision is made to remove any lumps that lodge in a bend in the suction pipe in a manner similar to that used in the Florida phosphate fields. The hammer mill and pump units are mounted on wide steel skids so that they can be moved as the mining operation progresses. The discharge from the pump flows through an abrasion-resistant spiral welded steel pipe 81/4 in. actual inside diam, 8 in. nominal diam, for a maximum distance of 2200 ft, which is the limiting pumping distance for one pump. This pipeline, referred to hereafter as pipeline A, discharges into a ball mill without balls, which in turn discharges into a rotary screen attached to it that separates the slurried matrix into 11/4-in. oversize and undersize fractions. The oversize is returned to the mill for further reduction; the undersize is pumped to a Dorrco washer and then flows into a hydroseparator 160 ft in diam. In spite of the size reduction in the hammer mill and the blunging and washing of the slurry in its passage through the pump, pipeline, mill, and washer, the discharge to the hydroseparator frequently contains mud balls almost perfectly spherical. Sometimes the discharge from the 16,000-ft pipeline at Godwin contains mud balls the size of bird shot and smaller. This pipeline will be referred to subsequently as line B. Liquid caustic is added to the slurry at the Akin plant before its passage through the hydro-separator, which decreases the size of particles in the overflow by dispersion. In passing through pumps 1, 2, and 3 and pipeline B, the slime fraction in the underflow is increased by abrasion and blunging and also by continuing dispersive action of the caustic. The matrix for use in the experimental tests referred to on p. 279 was obtained from three small surface openings on the Akin tract that were made previous to the purchase of the tract by the Authority. Matrix used in the 2 and 4-in. experimental pipeline tests was taken from the three openings and proportioned to obtain a sufficient quantity that would be fairly representative of the average in the Akin deposits. Prospecting samples of matrix had been obtained from drill holes which showed no small variation in physical and chemical properties. Some of the physical variation is evident from the size distribution of solids in samples taken during the tests covering line B flows so thoroughly made by the Authority und'er the direction of Mr. Burt, see Table V, p. 280. Hydraulic gradients for a pipe of 8-in. diam were derived from the 2 and 4-in. pipeline tests using the so-called representative matrix as above described, and plotted on the profile of pipeline B. Gradients of other materials in slurry form passing through pipelines that bore some similiarity to the Akin matrix slurry were also plotted. After a study had been made of the hydraulic gradients plotted on the profile and the varying slurry flow that would probably occur during actual operation, three pumps were ordered, referred to as No. 1, 2, and 3 on p. 279. No. 1 and 2 pumps were installed and the third kept in reserve should the operation of 1 and 2 pumps prove satisfactory, since installation of the third pump would require an attendant, as well as the laying of 5400 ft of pipe to supply it with seal-water from the Akin plant. Subsequently, it was found desirable to install the third pump to maintain capacity when the slime fraction was low and the coarse fractions were large. Reference to Fig. 6 will show that the flow in B line goes upgrade in three locations. At the outlet at Godwin, the slurry flows between two 45" bends for an approximate distance of 18 ft to rise above the ground a sufficient height to discharge into a launder feeding the first classifier. This condition requires extra energy, which is taken care of by keeping the hydraulic gradient a sufficient distance above the high points. Although there are rather heavy upgrades in the line, the choking condition that might occur at the

Jan 1, 1953

By R. B. Burt, J. A. Barr, I. S. Tillotson

DISCUSSION Howard Howie (Knoxville, Term.)—The authors are to be congratulated on the presentation of a paper containing so much valuable information on the pipeline transportation of phosphate, as there is very little literature on the subject. The writer is especially interested in the paper, as he conceived the arrangement of the Akin and Godwin plants and was in charge of the design work and the engineering incident to their construction. The Akin and other phosphate deposits in the Tennessee phosphate area lie on beds of limestone that are very irregular. The limestone beds, after the phosphate matrix has been removed, are similar in appearance to land severely eroded by the action of water and denuded of top soil. Depressions in the limestone, called cutters, are irregular in depth with vertical or overhanging walls, having the general appearance of cracks in dried clay. They change abruptly in direction, width, and depth, and vary on the Akin tract from 1 to 25 ft in depth and from 1 to 50 ft in width. Pinnacles of limestone commonly occur in the cutters which appear, when exposed, like small clifflike islands in a river. Limestone floats also occur. The phosphate matrix fills the cutters and covers the uncuttered areas, the thickness of the cover varying continually and sometimes rather abruptly. It occurs generally as stratifications of phosphate rock and clay of varying thickness. The phosphate rock in the matrix varies in hardness and in percents of silica, lime, iron oxides, and fluorine, and the clay varies in toughness. In some places the deposit consists of narrow strata of rock almost devoid of clay streaks. In other nearby locations the clay will predominate. When it is excavated, the phosphate rock breaks into thin irregular lumps, locally known as plate rock. Limestone lumps are also excavated with the matrix. Akin plate rock is generally much softer than that occurring in other deposits in the area. Because of the above described physical and chemical variations of the excavated material, the resultant slurry varies in size distribution, specific gravity, and percent of slimes. When the rock is soft or when there is an increase of clay, the slime fraction is greatly increased as it passes through pumps and pipelines, resulting in reduced pipe friction. It is obvious that the longer the pipeline the greater the reduction of coarse fractions into fines, causing a decrease in pipe friction that cannot be accurately evaluated. The matrix is mined with a dragline that drops it into a hopper with a grid composed of 9-in. parallel bar spacings located above the hammer mill. The matrix on, and passing through the grid, is subject to the action of powerful sprays which wash it down to the hammer mill, together with any limestone lumps that are not removed before passing through the grid. The hammer mill reduces the feed to lumps of plate rock and clay, most of which will pass through the 8-in. pump suction. The mixture discharges into a pool containing the pump suction pipe. Water from a hydraulic nozzle moves the mixture to the pump suction intake. The pump, driven by a variable speed motor, is the same size as the pumps mentioned on p. 279. Provision is made to remove any lumps that lodge in a bend in the suction pipe in a manner similar to that used in the Florida phosphate fields. The hammer mill and pump units are mounted on wide steel skids so that they can be moved as the mining operation progresses. The discharge from the pump flows through an abrasion-resistant spiral welded steel pipe 81/4 in. actual inside diam, 8 in. nominal diam, for a maximum distance of 2200 ft, which is the limiting pumping distance for one pump. This pipeline, referred to hereafter as pipeline A, discharges into a ball mill without balls, which in turn discharges into a rotary screen attached to it that separates the slurried matrix into 11/4-in. oversize and undersize fractions. The oversize is returned to the mill for further reduction; the undersize is pumped to a Dorrco washer and then flows into a hydroseparator 160 ft in diam. In spite of the size reduction in the hammer mill and the blunging and washing of the slurry in its passage through the pump, pipeline, mill, and washer, the discharge to the hydroseparator frequently contains mud balls almost perfectly spherical. Sometimes the discharge from the 16,000-ft pipeline at Godwin contains mud balls the size of bird shot and smaller. This pipeline will be referred to subsequently as line B. Liquid caustic is added to the slurry at the Akin plant before its passage through the hydro-separator, which decreases the size of particles in the overflow by dispersion. In passing through pumps 1, 2, and 3 and pipeline B, the slime fraction in the underflow is increased by abrasion and blunging and also by continuing dispersive action of the caustic. The matrix for use in the experimental tests referred to on p. 279 was obtained from three small surface openings on the Akin tract that were made previous to the purchase of the tract by the Authority. Matrix used in the 2 and 4-in. experimental pipeline tests was taken from the three openings and proportioned to obtain a sufficient quantity that would be fairly representative of the average in the Akin deposits. Prospecting samples of matrix had been obtained from drill holes which showed no small variation in physical and chemical properties. Some of the physical variation is evident from the size distribution of solids in samples taken during the tests covering line B flows so thoroughly made by the Authority und'er the direction of Mr. Burt, see Table V, p. 280. Hydraulic gradients for a pipe of 8-in. diam were derived from the 2 and 4-in. pipeline tests using the so-called representative matrix as above described, and plotted on the profile of pipeline B. Gradients of other materials in slurry form passing through pipelines that bore some similiarity to the Akin matrix slurry were also plotted. After a study had been made of the hydraulic gradients plotted on the profile and the varying slurry flow that would probably occur during actual operation, three pumps were ordered, referred to as No. 1, 2, and 3 on p. 279. No. 1 and 2 pumps were installed and the third kept in reserve should the operation of 1 and 2 pumps prove satisfactory, since installation of the third pump would require an attendant, as well as the laying of 5400 ft of pipe to supply it with seal-water from the Akin plant. Subsequently, it was found desirable to install the third pump to maintain capacity when the slime fraction was low and the coarse fractions were large. Reference to Fig. 6 will show that the flow in B line goes upgrade in three locations. At the outlet at Godwin, the slurry flows between two 45" bends for an approximate distance of 18 ft to rise above the ground a sufficient height to discharge into a launder feeding the first classifier. This condition requires extra energy, which is taken care of by keeping the hydraulic gradient a sufficient distance above the high points. Although there are rather heavy upgrades in the line, the choking condition that might occur at the

Jan 1, 1953

By J. F. Wolff

J. G. WOLFF, Duluth, Minn. (communication to the Secretary*).-In raising the question (" Newly Discovered Fossil Remains in the Cretaceous Shale," p. 1784) as to the possibility of the so-called Cretaceous remnants found on top of Mesabi Range orebodies really being Jurassic, the writer was acting under a wrong impression. In speaking of the matter with different geologists of note who have visited Northern Minnesota during the past year, lie understood one of them to refer to Jurassic shales existing quite extensively in Northwestern Minnesota. This apparently was entirely a misunderstanding. In answer to an inquiry in regard to this matter, Prof. W. H. Twenhofel, paleontologist at the University of Wisconsin, said that the known Jurassic nearest to Northern Minnesota is in Western Dakota. From the reproductions of fossils shown on p. 1785, Prof. Twenhofel tentatively correlated them as "middle-upper Cretaceous."

Jan 2, 1917

By W. F. Flanagan, K. R. Evans

The strong temperature dependence of the flow stress of bcc metals has prompted considerable interest and controversy concerning the rate-controlling influence of the Peierls' mechanism upon deformation in metals.18"21 Dorn and Rajnak" recently offered a criterion for Peierls' deformation utilizing a line-energy model of a dislocation to estimate the saddle-point activation energy, for the nucleation of a pair of kinks as a function of applied stress and the height and shape of the peierls9- barrier. It was found that Un/2Uk, where 2Uk is the excess energy of a kink pair, was a unique function of where is the effective stress and 7p is the Peierls' stress as defined in Fig. 20. The relationship found by Dorn and Rajnak between is given by the solid line of Fig. 21. may be expressed in terms of the temperature of test, T, and the athermal temperature, T,, defined in Fig. 20. Considering the strain-rate, 9, of deformation for a thermally activated process to be given by where fo is nearly a constant, it is seen that and the theoretical relationship of Fig. 21 may be examined with readily obtainable experimental parameters. Dorn and Coworkers analyzed a large amount of experimental data in this manner for materials sus-

Jan 1, 1967

By J. T. Norton, J. G. McMullin

E. R. JETTE*—The way this ternary was developed there are two directly determined points on each of the iso-thermals except the 700° isothermal, where I believe there is only one. How were the end points determined, and what was the basis for it? Whose work formed the basis for the silver copper line ? M. B. BEVER †—At most temperatures the authors determined three points of the isothermal line. For example it can be seen from Fig 3 and 4 how three points for the 600°C contour line were obtained. The authors took two additional points for each temperature from the copper-silver binary diagram contained in Hansen's volume on constitution diagrams. It is correct that the 700°C contour line is based only on one point in the ternary field which was found by a slight extrapolation of Fig 4. R. I. JAFFEE*—Are the tie lines representing phases in equilibrium parallel to the silver-copper boundary ? M. B. BEVER—Are you asking that as a matter of principle ? R. I. JAFFEE—I assumed that would follow from principle. I wonder if that is in accordance with the authors' ideas too. M. B. BEVER—I do not believe the authors obtained any information on the tie lines in the two-phase field. Of course, in the limiting case of very low gold contents the tie-lines approach to the silver-copper boundary, but generally in the two-phase field I do not think that the tie-lines have to be parallel to the boundary. E. R. JETTE—I am quite sure they do not have to be parallel. You cannot tell from this work in which direction they go. E. A. GULBRANSEN*—Were any pycnometric measurements made to check the lattice parameters of the alloys ? M. B. BEVER—I did not hear any-

Jan 1, 1950

By Henry Wurtz

HERACLITUS, a sage of antiquity, called the dark philosopher, who refused a throne, preferring a hermit's cell, propounded, twenty-four centuries since, the maxim : [ ] War (or strife) engenders all things. This, though probably intended by Heraclitus to apply especially to the internal forces of nature, is often said, with equal reason, of the affairs of men. Controversial strife, whether fortunately or unfortunately, is a crucible through which all new discoveries in science, and all technical applications of science must pass-a test which they must all endure before they can become so vitalized as to germinate, so to speak, take root in the human mind, grow tip, and overspread the earth. The greater the number and the power of the elements arrayed against such a growth, and of the influences hostile thereto, the greater should be the inherent vitality of the germ, the more strenuous, skilful, and persistent its cultivators and upholders. During the decade last past we have had, in spite of the severe stringency of the times, an active growth of this kind in progress, whose prospective importance it would now be difficult to overrate. This is the movement which has for its motive the idea that, generally speaking, fuel should be gaseous in form, and which has for its goal the introduction into general public use of gaseous products, made by cheap and rapid processes and on a gigantic scale, distributed throughout our cities and towns in distribution-systems which shall be proportionately gigantic, and sold at prices which will bring such fuel within the means of the poorest householders. Personally, for ten years past, the writer has never failed, on occasions public or private, to urge his belief that the realization of this idea, deemed by him a certainty of the future, will bring about

Jan 1, 1880

By Irwin H. Cornell

BRIEFLY stated, the history of the St. Joseph Lead Co. is the story of how a group of men, working for ten years as officers without salaries and stockholders without dividends, developed a small mine in Missouri into what became a large and prosperous corporation. Their courage and faith in the scattered surface deposits of lead coupled with the management's engineering vision and sound financial judgment should prove an inspiration to present-day mining operators and investors. In 1717, John Law's company, known as "The Company of the West," was formed in France and letters patent were granted, for a period of 25 years by Louis XV, for exploration in the Mississippi River Valley. One of the underlying purposes of the expedition, headed by Mr. Renault and Mr. La Motte, a French metallurgist, was development of the lead mines in the area now known as Southeast Missouri.

Jan 1, 1947

By A. B. Kinzel

SILICON and its metallurgical uses have been the subject of speculation since the earliest days of modern civilization. The early philosophers, Theophrastus and Pliny, believed that silica was a special form of ice, an opinion that was not seriously challenged until the seventeenth century. The first comprehensive view of the nature of silica was advanced by Lavoisier in 1787. He assumed silica to be an oxide of an unknown metal. In 1808 Berzelius produced ferrosilicon by heating silica, iron and charcoal. Probably the first produc¬tion of crystallized silicon was in 1854 when H. St. C. Deville accidentally produced the material while electrolyzing a double chloride of aluminum and sodium containing siliceous impurities. It is not strange that the early investigators should have given so much attention to silica and silicon, because of the great natural abundance of the former. Although silicon does not exist in the elemental state in nature, it has been estimated that the lithosphere contains approximately 60 per cent silica; quartz and rock crystal are found in practically every part of the world.

Jan 1, 1933

By John M. Lovejoy

FEDERAL regulation of the petroleum resources of the nation has long been an interesting topic for discussion. A plan to accomplish Federal control has now taken definite form. At the request of the President of the United States, a bill to be known as the Petroleum Conservation Act of 1939 has been presented to Congress-H. R. 7372, offered by Representative Wm. P. Cole, Jr., and more usually known as the Cole bill. It is an act ostensibly designed to conserve our petroleum resources, through regulation of production practices. Hearings are being held currently by a subcommittee of the Interstate and Foreign Commerce Committee, in compliance with the request of the President to report the bill early in the next session of Congress.

Jan 1, 1939

By ANDREW McVILLIAM, WILLIAM H. HATFIELD

AT the 1902 May meeting of the Iron and Steel Institute, the, authors presented a paper on " The Elimination of Silicon in The Acid Open-Hearth," wherein they recorded a few typical examples of certain Siemens charges out of a very large number specially watched for the purposes of that research. The main deductions drawn from those experiments have been accepted in all the intelligent criticism during or after the discussion on the paper. One opinion, however, was rigidly held by all who mentioned the matter, with the single exception, perhaps, of Mr. Lange, and that was the necessity for the attainment and the maintenance of an abnormally high temperature in order that the percentage of silicon in the metallic bath might increase, or that an unusually large proportion of silicon might be retained in the metal. The original decision was ar-rived at on the results of scores of trials, and has since been the subject of frequent experiment. The authors still retain their opinion that although, naturally, a higher temperature will accelerate the (probable) action between the carbon of the steel and the excess silica of the slag, they then fairly proved, and have now abundantly confirmed the fact, that around the temperatures occurring in Siemens steel-making practice the chemical composition of the slag, particularly with regard to its acidity, is the factor which determines whether the percentage of silicon in the molten steel shall increase or decrease. In the discussion in 1902 Mr. Saniter called attention to Mr. H. H. Campbell's work, and in the reply the authors also mentioned that of Messrs. Winder and Brunton of 1892, the two

Mar 1, 1905

By B. C. Allen, R. I. Jaffee, D. J. Maykuth

Wrought unalloyed iodide chromium, containing 39 to 95 ppm total interstitials, has a tensile transition temperature of —15°C. Re crystallizing at 1100°C causes the transition to rise to 90° to 390°C, depending on the purity, grain size, and cooling rate after annealing. At about the 100 ppm level, individual additions of carbon or nitrogen raise the transition of both wrought and recrystallized chromium by as much as 210°C, while oxygen has a lesser effect, and sulfur essentially no effect. High transitzon temperatures are exhibited by recrystallized and quenched chromium, and appear to be associated with the amount and distribution of inter-stitials. The latter cm be either in solid solution or in the form of precipitates within the grains or at the grain boundaries. Quench hardening in chromium is primarily caused by nitrogen. The hardness, re crystallization, and grain growth behavior of chromium with and without impurity additions were also investigated. BECAUSE of low density and good oxidation resistance, chromium-base alloys are potentially useful for elevated-temperature applications. The main deterrent to the use of chromium in structural applications is its lack of low-temperature ductility, especially in the recrystallized condition. Accumulated evidence has shown that the ductility of chromium is sensitive to purity. The objective of the current study was to determine the effect of common nonmetallic impurities on the tensile properties of high purity chromium. The separate effects of carbon, oxygen, nitrogen, and sulfur additions on the ductile-to-brittle transition were evaluated for wrought and recrystallized material after various cooling rates. EXPERIMENTAL WORK Unalloyed iodide chromium and seven impurity alloys containing individual carbon, oxygen, nitrogen, or sulfur additions were prepared in rod form. Nominal additions were 100 ppm C, N, and S, and 100 to 500 ppm O. The additions were about a factor of ten greater than the residual amounts in the unalloyed material. The seven alloys and two unalloyed compositions were consolidated into four-pound ingots by conventional consumable arc melting of pressed and welded electrodes under 0.5 atm of helium. Impurity additions were made to the electrode in the form of crushed master alloys. The impurity alloys were double melted to improve homogeneity. The ingots were broken down by extrusion at 1200°C in evacuated steel cans at a reduction ratio of 18 :1, using a molten borosilicate glass lubricant and a ram speed of 80 in. per min. The cans were removed by acid pickling, and the chromium core ground free of surface undulations. Cut lengths were sheathed in mild steel and swaged at 900°C until the core was about 1/4 in. in diam. Two additional 15-lb ingots of unalloyed chromium (ICr-3, ICr-4) were prepared by arc melting and broken down by 26:1 extrusion at 1250°C without a steel can. The billet was lubricated and protected from contamination by a coating of molten glass. The resulting extrusion was then sheath swaged as described previously. Representative chemical analyses of each of the materials, after removal of a 10-mil surface layer

Jan 1, 1963

By Henry Wurtz

Jan 1, 1880

By Wilbert G. McBride

Two Also 3 1/2-ton motor trucks were used by Young Bros. while operating at the Mammoth Collins mine at Shultz, Ariz. One was equipped with an oil tank holding 1,075 gal. and was used for the transportation of "tops." The other was fitted with a stake body and used to carry machinery, wood, rails, pipe and all classes of miscellaneous supplies. The bodies were made of oak with maple flooring and were attached to the frame of the chassis by U-bolts, to avoid drilling the main members of the frame. Most of the hauling was done from Tucson, a distance of 47 1/2 miles. During the first 3 months, part of the road was in very bad condition and the tire cost was excessive. After this part was repaired the road was in fair condition, but never good. There were no excessive grades or bad sand, but wagon ruts, too narrow for the truck wheels and of a different gage, caused heavy tire loss; while chuck holes, sharp curves and stones, both imbedded and loose, were objectionable features. During wet weather the trucks could not get sufficient traction to climb some of the hills and were likely to stick in the mud in certain places, so that no attempt was made to run them unless they were on the' road when the rain started. This lost time amounted to about 5 per cent. of the total, but, whenever possible, it was utilized in making minor repairs. The price of gasoline was from 17 to 21 c. per gal. Rubber tires were used throughout. Drivers were said $4.50 to $5 per shift, and a return trip to Tucson was counted as two shifts even when made in one day. Drivers were provided with a room in Tucson and were paid for a11 time lost due to causes beyond their control. Trucks were loaded one way only. Speedometers were placed on both trucks but the excessive vibration soon caused them to fail. For this reason, and because no account was taken of the distance covered in picking up a miscellaneous load or in other minor ways, the mileage given is under the actual distance traveled. Some of the weights had to be estimated, but care was taken to have the number of ton-miles low rather than high, to avoid underestimating the costs. The cost of hauling from Tucson to the mines was $12 per ton

Jan 1, 1917

By C. S. Barrett

W. Hofmann, J. Ziegler, and H. Hanemann—Having dealt with the same alloys in the winter 1941 to 1942, we want to give a short report on the generating of the hexagonal kappa phase by deforming the supersaturated alpha phase, which we then observed. This work was delivered as a Doctor of Engineering dissertation to the Technical University of Berlin by J. Ziegler in 1942. It still exists in two copies, somewhat damaged, a brief publication of it having been issued in Fiat-Review. Our work was started from the alloy Tombasil with 4.5 to 5 pct Si, 14.5 to 14 pct Zn, the rest Cu. Torpedo propellers were die cast from this alloy in Germany during the war. In order to improve this alloy, annealing was tried. By this treatment the alloy became at the same time harder and more brittle. A further research of this process was made in the Got-tingen University30 and the "Institut fÜr Metallkunde" of the Technical University of Berlin. It soon was apparent that the Cu-Si diagram at our disposal15,31,32 would not fit the observations. For this reason the pith of the matter became from then on the Cu-Si system. At that time we did not know of Smith's* and Andersen'sm latest diagrams. We first knew of them from Dr. Barrett's publication. Twenty-two alloys containing 2 to 11 pct Si were melted in a nitrogen atmosphere and generally homogenized for 2 to 4 hr at 800 °C. Part of the samples were then annealed at 700°, 600° and 500°. Annealing was followed by quenching in water. The phases corresponding to the various temperatures were identified by X-ray and microscopy. The Debye-Scherrer photographs generally were made of filings. The latter were produced after the last anneal of the samples, then equally annealed another 30 min in evacuated glass tubes and quenched in water. In the region of concentrations examined, the Cu-Si phases already known to us were observed: alpha, kappa (then called beta by us), gamma. By hot exposing an alloy of 7.69 pct Si at 800" and 750°,

Jan 1, 1951

By L. G. Jones, A. S. Odeh

A theoretical developtment is presented which provides a straightforward method of handling the drawdown analysis for both oil and gas wells flowing at variable rates. In the past our inability to analyze variable-rate drawdowns has been a major obstacle in using them for formation evaluation. This method should permit wider use of these tests in the future. INTRODUCTION Pressure build-up analyses are widely used to obtain reservoir data such as the effective flow capacity of the formation. On the other hand. although pressure drawdowns have been run for a long time, they have not been used extensively to evaluate reservoirs because they are difficult to analyze. One of the difficulties in analyzing pressure drawdowns has been that the theory developed until now has required the test to be run at a constant rate. For both oil and gas wells this is a difficult requirement to satisfy. especially during the early period of a well's life when drawdown tests are usually run. In spite of this limitation, drawdown tests are often run with build-ups as a check. In this paper a theory, which handles the drawdown analysis for variable rates, is presented for both oil and gas wells. Thus, one of the biggest deterrents to running drawdowns is removed, and they should become a much more useful engineering tool in the future. THEORETICAL CONSIDERATIONS 011, RESERVOIRS The general equation used for describing the unsteady-state radial flow of slightly compressible fluids in homogeneous porous media can be written in cylindrical coordinates as where r is the radial distance in cm, t is the time in seconds, p is the pressure at r and t in atmospheres, + is the fractional porosity, p is the viscosity in cp, c is the compressibility in vol/vol/atm, and k is the permeability in darcies. There are a number of solutions of Eq. 1 for various boundary conditions. One of these is the so-called "point-source" solution, which approximates the case of an infinite oil reservoir with a well located at r = 0 and produced at a constant rate. The point-source solution of Eq. 1 is

Jan 1, 1966

By R. F. Miller

DUE to wartime secrecy restrictions a large part of the technical information developed by government and industrial laboratories was withheld from distribution. Much of this information has now been released or "declassified" and reports of technical work carried out during the war in allied and enemy countries are also becoming available. Information on the latter subject has been augmented by the work of the Technical Industrial Intelligence Corps of the U. S. Army. Through the Joint Chiefs of Staff, rep¬resentatives of this Corps co-operated with the British Combined Intelligence Observations Subcommittee, and some of the observations were made by combined personnel of both groups. The U. S. Government has undertaken the indexing and abstracting of all of this information in the Bibliography of Scientific and Industrial Reports, a weekly bulletin which appeared first early in 1946. Other publications, such as the Bulletin of the British Iron and Steel Institute and The Metals Review of the American Society for Metals, provide abstracts of domestic and foreign magazine articles and papers presented to technical societies. However, they do not cover the industrial and government reports recently released by the Government nor the reports of the Army investigators hence the new bibliography is a welcome addition to our metallurgical library.

Jan 1, 1947