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By A. Mitchell, T. Bagshaw

A recent paper by Thomas1 has presented new data on the solubility of hydrogen in solid silver at 1 atm pressure in the temperature range 600° to 963°C. However, no data is reported in the literature on hydrogen solubility in liquid silver. The Sieverts technique which has been described previously2,3 was used in the present work. Charges of approximately 160 g were melted in Morgan "purox" recrystallized alumina crucibles and purified helium was used for the determination of the "hot volume" during each experiment. A chemical analysis of the silver indicates that the impurity content (Cu + Al) is less than 0.02 wt pct. Hydrogen solubility in the temperature range 963° to 1200°C was investigated. The results of three experiments are shown in Table I. Fig. 1 shows an Arrhenius plot of the present work together with the solid-state data of Thomas, Steacie, and johnson,4 Eichenauer et al.,5 and Siegelin et al.6 The following expression has been derived from the Arrhenius plot of the present data: log (solubility of hydrogen, cm3 per 100 g) = 2.154-3512.0/ToK The heat of solution derived from Fig. 1 is 31,150 cal per g mole H2 compared with the value of 33,020 cal per g mole H2 obtained by Thomas and 12,000 cal per g mole H2 obtained from the data of Steacie. It was observed that hydrogen evolution took place when the silver melts were solidified under 1 atm of hydrogen, which would not be expected from an extrapolation of the results of Steacie. Schenck and Lange7 have observed that, for several transition metals at their melting points, the ratio of the hydrogen solubility in the liquid to that in the solid lies in the range 2.1 to 3.1. The present results and those of Thomas are in accord in this respect having a ratio of 2.8. 'C. L. Thomas: Trans. TMS-AIME, 1967 vol. 239, pp. 485-96. 2T. Bagshaw and A. Mitchell: I. Iron Steel Inst., 1966, vol. 204, p. 87. 'M. Weinstein and J. F. Elliott: Trans. TWS-AIME, 1963, vol. 227, p. 382. 'E. W. R. Steacie and F. M. G. Johnson: Proc. Roy. Soc. (London), Ser. A, 1928, vol. 117, pp. 662-79. 'W. Eichenauer et al.: Z. Metallk., 1958, vol. 49, pp. 220-25. 6W. Siegelin et al.: Z. Elektrochem., 1957, vol. 61, pp. 359-66. 'H. Schenck and K. W. Lange: Arch Eisenhuettenw., 1966, vol. 37, no. 9, pp. 739-48.

Jan 1, 1969

By J. P. Dovel

HAVING been requested to prepare a paper referring especially to my patents as applied to blast furnaces, I shall confine my discussion to those improvements and inventions pertaining directly to the blast furnace itself, omitting a number of patents pertaining to blast furnace operations. I spent the early part of my life in the construction of blast furnaces, from rivet-heating to drafting and designing, much of the work relating to repairs and rebuilding. Later, as I became more interested in maintenance and operation of a group of blast furnaces, one fact especially made a lasting impression on me, namely that a very expensive piece of equipment was very short lived, and the expense of replacement, relining, etc., in many instances consumed most of the profits made while in actual operation. As far back as 1910, I began to lay plans to build with a view to permanency and not merely for a blast, the common expression at that time, which really meant only one or two years in southern practice. Since we did not then blow so hard most failures occurred in the bosh and hearth. The failure of either generally meant a complete new lining, as the inwall did not look good enough to last another blast. At that time we were using two types of hearth, one of heavy steel plate protected by well and sprays on the outside, and .one of heavy. cast iron, made in sections and bound together with wrought-iron bands. The former type proved dangerous, for if the iron should come through, as it frequently did, it would cut away the steel plate, quickly turning large quantities of molten iron into the water, causing a severe explosion and costly repairs. The cast-iron type gave trouble also by the iron finding its way through the joints between the sections, which was' not so serious; since the iron would not cut away the heavy cast-iron sections very quickly, and generally caused only small damage, and repairs-were easily made. Both types have been improved; the former by the introduction of cast-iron -water-cooled plates, placed on the, inside of the steel, jacket. This has proved to be very good construction, but has no real claim to permanency: As the cast-iron plates cannot be replaced from the outside, therefore the operator must assume that some time, at no late date, he must replace them from the inside, which will mean a blowing out of the furnace. The heavy cast-iron hearth has been improved by making the

Jan 1, 1928

By William Clark

A bean placed at the bottom of tubing in flowing wells is not a new idea. In fact, a device which in effect was a bottom bean was patented prior to 1890 by John D. Rockefeller. Because of the limited use of the bottom bean, prior to 1922, when it was installed in a few wells in the Santa Fe Springs field, California, the knowledge of the results of its operation is very meager. Since then various oil operators have experimented with bottom beans, but most of the records of the results obtained by their use are unavailable. For the past year or two, more attention has been directed to this method of producing wells; the theory and best means of application have been studied, and accurate records maintained. In theory, the use of bottom beans in flowing or gas-lift wells should secure certain advantageous results. With the exception of flow friction of the tubing and flow lines, there is no back-pressure held on the rising column of fluid. Thus severe beaning is possible with no danger of killing the well by too heavy a fluid column, a condition that often exists when a surface bean is used. The whole energy of the gas expanding to atmospheric pressure is utilized to lift the fluid in the well. The same effect is obtained when flowing a well through open tubing or casing. In using a surface bean this energy of expanding gas is wasted into the flow lines beyond the bean, because the fluid has reached the surface by the time the restriction is reached and the work of the gas performed. The bottom bean affords an efficient use of the expanding force of gas, utilizing less gas to raise the same amount of oil, hence allowing for lower gas-oil ratios. The flow restriction being at the entrance to the flow string, a more uniform mixture of gas and oil enters the tubing and a steadier backpressure is held on the well. The uniform mixture and high velocity attained while flowing through the bean, which is above the critical velocity required to suspend a spray condition of gas and oil, prevent slippage of gas, surging and heading with its resultant strain on the casing. The advantageous conditions allow positive control of production in gas-lift wells within limits set by the bean size and amount of input gas; and probably help to prevent sanding up of a well and the coning

Jan 1, 1931

By John Guillermo Bartram

The oil industry continued relatively quiet in Wyoming in 1935, although production increased about 8 per cent over the previous year; 55 oil wells were completed in 1935, compared to 34 in 1934, and at the end of the year 44 wells were drilling, 33 in proven fields and 11 in wildcat locations. The total drilling a year ago was only 30. In the year 1935 Wyoming produced a total of 13,451,000 bbl. of oil, a gain of 912,000 bbl. over the 1934 figure of 12,539,000 bbl. Approxi-mately two-thirds of the increase, or 630,000 bbl., was from black oil fields and one-third, or 285,000 bbl., from light oil pools. Salt Creek, with production of 6,357,000 bbl., is still many times the largest field in Wyoming but in 1935 it made less than 50 per cent of the state's total, after producing more than all other fields in the state for 24 years; however, its decline was only 3.8 per cent from the previous year. Oregon Basin, a black oil field, held second place again with production of 1,163,-000 bbl., a good increase over 1934. Grass Creek, with increases in both its light and black oil, jumped into third place; and Lance Creek, with its new Sundance light oil production, was in fourth place in the amount of production. Frannie, which was in third place in 1934, dropped far back on the list because of lack of market. Byron and Garland, two other black oil fields in the Big Horn Basin, increased considerably. Big Muddy, a prominent light-oil field, was down with a natural decline; and Elk Basin, also light oil, produced less because of market conditions. During 1934 only three gas wells were drilled in Wyoming and 29 dry holes, 13 in proven fields and 16 at wildcat locations. Of the latter, 5 were on wildcat structures of considerable interest. Of the 55 wells completed during the year, 53 were in proven fields and of these 17 were small ones in the shallow Osage field and 10 were light-oil wells good for 1500 to 3000 bbl. each in the Lance Creek field. Discoveries Two of the oil wells were discoveries at Medicine Bow and Sheep Creek. Medicine Bow is a very large anticline with more than 3500 ft. of closure and is located in Carbon County in the south-central part of the state. In 1923 it showed some oil in the Upper Cretaceous Frontier

Jan 1, 1936

By John Guillermo Bartram

The oil industry continued relatively quiet in Wyoming in 1935, although production increased about 8 per cent over the previous year; 55 oil wells were completed in 1935, compared to 34 in 1934, and at the end of the year 44 wells were drilling, 33 in proven fields and 11 in wildcat locations. The total drilling a year ago was only 30. In the year 1935 Wyoming produced a total of 13,451,000 bbl. of oil, a gain of 912,000 bbl. over the 1934 figure of 12,539,000 bbl. Approxi-mately two-thirds of the increase, or 630,000 bbl., was from black oil fields and one-third, or 285,000 bbl., from light oil pools. Salt Creek, with production of 6,357,000 bbl., is still many times the largest field in Wyoming but in 1935 it made less than 50 per cent of the state's total, after producing more than all other fields in the state for 24 years; however, its decline was only 3.8 per cent from the previous year. Oregon Basin, a black oil field, held second place again with production of 1,163,-000 bbl., a good increase over 1934. Grass Creek, with increases in both its light and black oil, jumped into third place; and Lance Creek, with its new Sundance light oil production, was in fourth place in the amount of production. Frannie, which was in third place in 1934, dropped far back on the list because of lack of market. Byron and Garland, two other black oil fields in the Big Horn Basin, increased considerably. Big Muddy, a prominent light-oil field, was down with a natural decline; and Elk Basin, also light oil, produced less because of market conditions. During 1934 only three gas wells were drilled in Wyoming and 29 dry holes, 13 in proven fields and 16 at wildcat locations. Of the latter, 5 were on wildcat structures of considerable interest. Of the 55 wells completed during the year, 53 were in proven fields and of these 17 were small ones in the shallow Osage field and 10 were light-oil wells good for 1500 to 3000 bbl. each in the Lance Creek field. Discoveries Two of the oil wells were discoveries at Medicine Bow and Sheep Creek. Medicine Bow is a very large anticline with more than 3500 ft. of closure and is located in Carbon County in the south-central part of the state. In 1923 it showed some oil in the Upper Cretaceous Frontier

Jan 1, 1936

By J. W. King

URANIUM ore was first discovered in the Edge-mont district of the southern Black Hills in the summer of 1951. The discovery was not made known for some time, but after the news leaked out prospecting became intense, and several hundred claims were staked in the spring of 1952. The Hot Springs Sub Office of the Atomic Energy Commission was established at that time and airborne radiometric surveys were commenced by the Government and by private companies. During the succeeding summer another important discovery was made by private airborne surveys in the northern Black Hills, and the area favorable for uranium ore was expanded many times. Between that summer of 1952 and the present, many individuals and groups have explored, developed, and exploited their claims until now uranium ore is produced in significant quantities and substantial reserves have been developed. The Black Hills portion of the geologic map of the U. S. issued by the U. S. Geological Survey is shown in Fig. 1. Sedimentary formations are exposed as a series of cuestas and hogbacks in a roughly annular pattern with the older sediments resting on the pre-Cambrian core, which is exposed in the eastern and southern portions of the dome. The South Dakota-Wyoming state line bisects the area from north to south. The Cheyenne River crosses the southern tip of the Black Hills and the Little Missouri bounds them roughly on the north. Headquarters of the AEC in the Black Hills is the Sub Office at Hot Springs, S. D. An ore buying station is located in Edgemont, 28 miles to the southwest, where a mill is presently under construction. The area of original uranium ore discovery and of principal activity in the southern Hills is a few miles north of Edgemont. Several areas of anomalous radioactivity have been noted between Dewey, S. D., and Newcastle, Wyo. A limited amount of ore has come from the Dewey area and private exploration is active there. The Carlile deposit, largest producing mine in the northern Black Hills to date, lies northwest of the Belle Fourche River near the western extremity of the Hills. Two of the larger known orebodies of the area are located near the Little Missouri River where a small window exposes the favorable strati-graphic horizon of the Fall River sandstone. Small production has recently come from Barlow Canyon, near Devils Tower, Wyo., Fig. 2, and numerous areas of anomalous radioactivity are known in the vicinity. Three producing deposits and scattered radioactivity are found along the state line east of Aladdin, Wyo. Several areas of weakly anomalous radio-

Jan 1, 1957

Book Review Mexico, TODAY AND Tomorrow. By E. D. Trowbridge, Detroit. The McMillan Co., New York, 1919, 353 pp., 7;2 X 5 in. $2.00. The first eight chapters are devoted to an historical narrative of the Mexican peoples from the earliest times to the close of the war with the United States in 1345. "In dealing with events antedating what may be termed modern Mexico" the author has "made no attempt at original research, and so far as concerns anything prior to 1900, the work here presented is a repetition, a reflection, of the findings of opinions of Fiske, Prescott, Bancroft, Luis Perez Verdia and other authorities." The remainder of the hook deals with Mexico during and since the Diaz regime. It is interesting throughout but is not always convincing or consistent. Social conditions are described in a way illuminating and possible only to one who is familiar with the peon and his hitherto seemingly hopeless position in reference to the wage system and church oppression. In fact, the author makes the hold accusation that the "primitive rather than immoral" condition of the peons in the matter of their marital relations is due to the disregard of the church for their welfare and capabilities. The true accounts of the Madero revolution and the Huerta regime read like fascinating medieval fiction. The reason given for men remaining in the Madero army is still the controlling one regarding any of the armies there. "They had horses, arms, all the food they wanted, money to spend and no work." The discussion of Mexican financial schemes is wholly from the Carranza viewpoint. To meet a monthly deficit of ten million pesos the author says "the government forced loans from the National Bank, and Bank of London and Mexico, and repeated the operation several times, finally practically exhausting their bullion and cash reserves. Hostile foreigners refer to this operation as the looting of the hanks! Drastic as this action was, there was good ground on which to justify it." However, that necessity knows no law is never an acceptable tenet except to him who applies the screws. The discussion of the economic problems and their solution is rather chimerical and presupposes a civil and national virtue in the present government not discernible except to one ultra friendly. The book is an interesting exposition of the very much involved situation from the viewpoint of approval of both the Carranza government and the attitude of the United States in its dealings with him. The editing of the book leaves something to he desired. P. E. B.

Jan 9, 1919

By C. P. Mangelsdorf

The roof truss as a means of secondary or supplemental mine roof support has enjoyed increasing acceptance in recent years, particularly in bituminous coal mines. In those entries where long life is required or doubtful performance from other forms of support seems likely, trusses in many cases have provided the necessary protection for continuing operations. Although relatively expensive and time-consuming in their installation, trusses, particularly with the new resin point anchor system, appear to be justifying their higher premium. It seems inevitable that techniques and equipment for installing them within the cycle will soon be developed. The actual mechanism by which trusses contribute to the stability of a roof is, as yet, poorly understood, and it may be that more than a single mechanism is involved. There are, however, a number of useful observations which can be made concerning the structural behavior of the truss itself, based solely on the mechanics of rigid and deformable bodies. The purpose of this article is to present some of these observations, particularly relating to friction in the system. A few speculations concerning the roof must, of course, be made. From a knowledge of the structural behavior, some insight into the truss-roof interaction may be gained. The concept of the truss is quite simple. As shown in [Fig. 1], it consists of two inclined chords (usually at 45') anchored in holes drilled in the roof over the ribs. A horizontal chord is formed connecting the exposed ends of the inclined chords, either with a third piece or by bending extensions of the inclined chords until they meet in the middle. A distinction can be made between active and passive chords of a truss depending upon the manner of installation. If the inclined chords are fully grouted and the horizontal chord is merely attached to them, it may reasonably be assumed that no significant forces exist in the truss until the roof begins to work. Such would be a completely passive system. On the other hand, if the inclined chords are anchored only at their upper extremities and the horizontal chord is formed in such a way that all three chords can be pretensioned to a significant portion of their tensile strengths then the truss may be regarded as fully active. Combinations of active and passive chords are also possible. * The discussion here is confined to the fully active truss such as the Birmingham steel rod system or the Galis wire rope truss. In both cases, pretensioning is accomplished by tightening of the horizontal chord, some of which tension is transferred to the in-

Jan 1, 1981

By F. J. Radd, R. L. McGlasson

The mechanisms of corrosion and corrosion fatigue damages to sucker rods are examined from a fundamental electrochemical viewpoint, and the relationships of sucker rod microstructures to these damaging effects are defined. The common corrosive agents in crude oil production and storage are discussed as to types of attacks that they cause. The variations of fatigue strength with alloy content, surface preparation, and stress ranges are analyzed. Finally, conclusions are drawn as to how microstructures largely influence and control sucker rod performance. INTRODUCTION Greater than 90 per cent of the crude oil produced by artificial lift methods is produced through sucker rod pumping systems. In the USA each year more than $14 million is spent for sucker rods in new and old pumping installations. It is important to make this investment a wise one. Essentially, the sucker rod system is a long series of steel rods, operating under alternating stress loadings and under mechanical vibrations, which connect the surface power source with the subsurface pump. These rods often operate in a variety of corrosive media, including water, brines, carbon dioxide, hydrogen sul-fide, and air. Basically, this paper is concerned with the problem of the behavior of certain steels in various corrosive media under high and dynamic stress patterns. The main objective of this paper is to show how, once the stress effects and the corrosive environments are defined, one can still realize structural control and beneficial influence upon corrosion and corrosion fatigue. FUNDAMENTAL DEFINITIONS AND ANALYSIS In the corrosion and stress behavior of this solid state mixture of iron and iron carbide called steel, one must analyze upon what major factors does its service life depend and of what, exactly, is steel composed. The former question can be referred to two external factors and two internal factors. The two major external factors are: 1. the nature of the stress patterns — size and range of stresses present 2. the nature of the corrosion — erosion environment — the corrodent and/or wear involved The two fundamental internal factors that govern the strength and useful life of a steel both in normal duty and in heavy-duty corrosion service are: 1. the nature of the steel volume properties 2. the nature of the steel surface properties For the latter question normal steel is defined as a solid mixture of iron and iron carbide particles, generally with certain accidental and intentional elements present. (The amount of iron carbide present is determined by the carbon content of the steel.) These additional elements generally dissolve into either the iron (ferrite) or the iron carbide (cementite) components.

Jan 1, 1955

By R. E. Hurst, D. E. Ramsey, J. M. Moore

The "frac" method of well stimulation has been applied successfully to all producing formations in the Permian Basin area. During the five years since its development, many changes and improvements have been made in treating materials. procedures, and equipie11t. A number of fluid carrying agents, having different physica1 and chemical properties, have been developed to meet variorus well requirements. The current trend is toward larger gallonage treatments, employing higher injection rates. The use of "down-the-casing" techniques has greatly reduced high surface working pressures, attributable to friction losses resulting from injection throrugh tubing. Petrographic studies of various Permian Basin formations, coordinated with laboratory and well log data, have been found a valuable guide in planning frac treat111o1t.s. A knowledge of the extent (and orientation of naturally occurring fractures and planes of weakness in the formation, aid in predicting the ultimate drainage pattern resulting from the frac treatment. INTRODUCTION The South Permian Basin covers an area in Wcst Texas and New Mexico about onc-half the size of the state of Texas, This vast region has been called the "Permian Basin" for so long that the term will he used here. It includes an area south of the Matador Arch. approximately 250 miles wide and 300 miles long. Structural features of importance within the basin are the Northwest Shelf, Eastern Platform, Midland Basin, Central Basin Platform, and Delaware Basin. The principal producing formations include sand, limestone and dolo-mite, with lesser amounts of shale, anhydrite. chert. and various silicates. All of the producing formations in the Permian Basin have responded to some type of frac treatment. Essentially, a frac treatment may be defined as the injection, into a formation. of a fluid carrying agent containing a particulated solid (usually sand), for the purpose of increasing production. The application of this method of well stimulation to many differing Permian Basin reservoirs has necessitated numerous changes and improvements in carrying agents, solids, service equipment. well equipment. and treating techniques. CARRYING AGENTS A number of different types of fluid carrying agents have been developed since the introduction of the frac method of well stimulation. These agents have different physical and chemical properties, and in many cases the extent of production increase derived from the frac treatment depends on the choice of fluid carrier. Unfortunately, due to many different systems of nomenclature used in the oil field, these differences are not always recognized by the oil Operator. In general, carving agents may he divided into the following broad classi-

Jan 1, 1956

By L. Frank, Nason

THE complete statistics of zinc-ore production in the United States for 1916 are not yet available. The following figures are, therefore, only approximate. The total production of concentrates for this year, including New Jersey and Tennessee, amounts to 1,280,000 tons. Of this tonnage, five mines produced approximately 536,000 tons, or about 42 per cent. The remaining concentrates came mainly from the "Valley States," Missouri, Wisconsin, Kansas, Oklahoma, and Arkansas. The 1,280,000 tons of concentrates represent about 25,000,000 tons of crude or run-of-mine ore. Of the five mines producing the 42 per cent., the dimensions of three are approximately 25 by 1,500 by 2,000 ft. (7.6 by 457 by 610, m.) or more. Tour of the five mines are undoubtedly veins in the common acceptance of the term. They are located in great vein systems. The mines of "Valley States" have not, so far, been classed as veins; simply as "secondary deposits." The origin of these secondary deposits has been a warmly debated subject. Many geologists contend that they are the results of leaching from overlying and from adjacent rocks carrying but traces of zinc, these traces leached out and deposited in favorable loci. If this theory is correct, deposition is strictly limited to shallow depths. No volume of ore comparable to that of "true fissure veins" is to be expected. Just what this means to the future of zinc mining in these States is here indicated. The total zinc areas of these States amounts to about 9,124- sq. miles (23,631 sq. km.).- Assuming that 10 per cent. of this total will be more or less productive, there are 912 sq. miles (2,362 sq, km.) of "mineral? ground. The average depth of the operated mines is something like 100 ft. or less. In Bulletin 606, U. S. Geological Survey (1915), p. 202, Siebenthal makes the following statement: "The writer is informed by William Waugh, one of the drillers of the Stone City well, that cuttings from other wells which he drilled in the vicinity of Pittsburgh, Kan., have shown galena and sphalerite taken from a depth of 591 ft. (180.14 m.) and that the showing of ore at some places would be considered good enough to justify the sinking of a shaft had it been found in the Joplin district and at shallower depths." Leaving out of the question the prohibitive cost of such a shaft, there is

Jan 5, 1917

By A. S. Appleton, M. B. Bever, G. E. Dieter

A gold-silver alloy was deformed by explosive loading at shock pressures up to 510 kbars. The stored energy and hardness increased over the whole range of pressures; the largest rates of increase were observed between 120 and 150 kbars. In this range, markings rkavacteristic of defornation twins first appeared; higher pressures produced markings in all grains. These effects are compared with those of conventional deformation processes and are discussed in relation to probable structural changes. In recent years, increasing efforts have been devoted to the investigation of the effects produced in metals by the passage of high-intensity shock waves of explosive origin. By properly utilizing the energy released by the detonation of a high explosive, it is possible to generate pressure pulses of the order of 500 kbars and higher. (One kbar equals l0 9 dynes per sq cm or approximately 1000 atm.) The passage of a shock wave through a metal occurs at pressures which are very much greater than the yield strength. As the shock front passes a point in the metal, the pressure rises almost instantaneously, and continues to act at the point for a few microseconds. Thus, metals subjected to explosive shock loading experience a nearly instantaneous increase in pressure, and a subsequent release of pressure, which is almost as rapid. Under these conditions mechanical twinning and shear transformations occur readily. smith1 has investigated the metallurgical changes in copper and iron resulting from exposure to explosive shock waves. He found an appreciable increase in hardness in both metals. In copper, a hardness greater than that resulting from 95 pct reduction in thickness by rolling was obtained, yet in the explosive deformation, the thickness of the specimen decreased only a few percent. After explosive loading, the micro-structure of copper showed markings characteristic of mechanical twins. The amount of stored energy resulting from explosive loading is of interest. Measurements of the stored energy of cold work as a function of strain, temperature, strain rate, and composition have been made with gold-silyer alloys deforyed by rolling, orthogonal cutting,3 drilling,4 filing, wire drawing, and torsion. The investigation reported here was also carried out with a gold-silver alloy and its results can be compared with those for the deformation of this alloy by more conventional methods. EXPERIMENTAL PROCEDURES An alloy containing 82.6 wt pct Au and 17.4 pct Ag was purchased in several batches from Handy and Harman Co., New York, as annealed rod 1/4 in. dim. The rod was cold-rolled to a sheet approximately

Jan 1, 1962

By Frank L. Nason

The complete statistics of zinc-ore production in the United States for 1916 are not yet available. The following figures are, therefore, only approximate. The total production of concentrates for this year, including New Jersey and Tennessee, amounts to 1,280,000 tons. Of this tonnage, five mines produced approximately 536,000 tons, or about 42 per cent. The remaining concentrates came mainly from the "Valley States," Missouri, Wisconsin, Kansas, Oklahoma, and Arkansas. The 1,280,000 tons of concentrates represent about 25,000,000 tons of crude or run-of-mine ore. Of the five mines producing the 42 per cent., the dimensions of three are approximately 25 by 1500 by 2000 ft. (7.6 by 457 by 610 m.) or more: Four of the five mines are undoubtedly veins in the common acceptance of the term. They are located in great vein systems. The mines of "Valley States" have not, so far, been classed as veins; simply as "secondary deposits." The origin of these secondary deposits has been a warmly debated subject. Many geologists contend that they are the results of leaching from overlying and adjacent rocks carrying but traces of zinc, these traces leached out and deposited in favorable places. If this theory is correct, deposition is strictly limited to shallow depths. No volume of ore comparable to that of "true fissure veins" is to be expeeted. Just what this means to the future of zinc mining in these States is here indicated. The total zinc-bearing areas of these States amount to about 9124 sq. miles (23,631 sq. km.). Assuming that 10 per cent. of this total will be more or less productive, there are 912 sq. miles (2,362 sq. km.) of "mineral" ground. The average depth of the operated mines is something like 100 ft. or less. In Bulletin 606, U. S. Geological Survey (1915), p. 202, Siebenthal makes the following statement: "The writer is informed by William Waugh, one of the drillers of the Stone City well, that cuttings from other wells which he drilled in the vicinity of Pittsburgh, Kan., have shown galena and sphalerite taken from a depth of 591 ft. (180.14 m.) and that the showing of ore at some places would be considered good enough to justify the sinking of a shaft had it been found in the Joplin district and at shallower depths." Leaving out of the question the prohibitive cost of such a shaft, there is

Jan 1, 1918

By G. W. Thompson

G. W. THOMPSON,* Brooklyn, N. Y.-This subject has two aspects, neither of-which can be ignored: these are the economic aspect and the technical aspect. Under ordinary conditions, economic law will take care of the conservation of tin. Under present conditions it seems desirable that economic law should still be permitted to operate as far as is practicable. It is true that this law operates rather slowly, and that under war conditions it cannot be depended upon to give our Government the supply it immediately needs. There should, therefore, be a designation of the essential industries by the Government, and tin should be supplied for those needs, letting the non-essential industries take what is left. At the same time, information ought to be forthcoming as to how tin can be conserved; with tin selling at 80 c. per pound, more or less, it is to the interest of every consumer to get the best information he can as to how he can save tin. Economic law would properly punish those who do not study their own interests in this way. I deprecate, therefore, any centralized socialistic effort toward avoiding penalties through failure to observe and obey economic law. In saying this, however, I am not unmindful that it is desirable for our Government to take such control of the tin situation as may be necessary to the prosecution of the war, practically regardless of the effect of such action upon individual industry, which should studiously seek to adjust itself to the new condition. The Government should promulgate such technical information as it can collect, showing how tin can be conserved, and should urge upon every consumer the exercise of his common sense in self-protection. There is very little danger of any one attempting to hoard or corner tin, in the present state of the market. Most consumers will be glad to live from hand to mouth, covering their sales by purchases, or vice versa. As to the technical aspects: Tin and tin alloys are used to give certain practical and also certain artistic results. The practical factors are those involved in proper adhesion, continuity of surface, protection, the right degree of hardness, proper working qualities, etc. The artistic results are those that appeal purely to the eye or to our cultivated sense of what is desirable. There is no doubt that a great deal of tin could be saved if there were not a demand for certain pleasing effects. How can this saving be brought about? The users of tin hearing alloys are not the only ones involved in this question. The manufacturers of solder and babbitt have for a long time sought to give certain appearances to their fabricated bars and ingots in order to make them more salable. The user of a solder is very apt to judge of its working qualities by the appearance of the bar; the same thing is true with regard to babbitts. Under ordinary conditions, manufacturers are justified in trying to

Jan 12, 1918

By H. Furman Byars

INTRODUCTION of bottom dump hauling units into the Ray, Ariz., stripping operation of the Isbell Construction Co., was motivated by several reasons, with what appears to be debatable results. The accepted theory of truck design for use in open-pit holds that end dump vehicles are the most adaptable for the work. But, because operations of the bottom dump, under certain construction and haulage conditions, proved economically feasible, the unit was put to work in the Ray copper pit. The decision to try bottom dump was reached after considerable observation of the unit in action on construction of earth filled dams, levees, airport construction and several other similar tasks. Basic tire design also motivated the choice. All things being equal, a vehicle running on low pressure single tires will outperform another operating on dual high pressure tires, providing load carrying capacities are the same. The investment required to equip a vehicle with four single tires to handle the same load as one with dual tires mounted on two axles and single front axles is about 60 pct greater. Thus, in order to reach the break even point on tire costs, single tires must operate 60 pct longer. Comparison is made with a truck outfitted with 10 16:00x25 tires. Two other factors were considered in selecting bottom dump trucks. It was felt the bottom dump principle would work well in dumping ore into a hopper where gate design fits this particular method. Also, with the absence of hydraulic dumping, ore pollution with oil is reduced. The mechanical simplicity of the unit also lent weight to its choice. Ordinary reasoning indicated maintenance costs would be low compared with other units carrying similar loads. The bottom dumping principle is not new. It dates back to the days when horses were used to haul the same kind of rig. The unit employed at Ray holds 25 cu yd struck measure, or approximately 42 short tons. Dumping is accomplished by releasing an air cylinder opening a dog holding the doors. Doors are closed by a cable system operating off a wheel wind deriving power by friction with the trailer tire. The unit is mounted on four 27.00x33 and two 14.00x24 tires on the front axle. The power unit is a 300 hp Cummins engine. Hydraulic power boosts the steering. A straight mechanical drive and friction clutch with 10 speeds is used. Conditions Not Ideal Top performance of the truck can be expected only under the conditions for which it was designed, in particular grades under 5 pct, handling fine material, and dumping where one thin layer can be placed on top of another. The machine will handle 42 tons per haul, operating at high speed, with only seconds used for dumping. On a 2 or 3 pct grade over a one mile haul,

Jan 1, 1952

By Harry Udin

IN 1948, the writer and his associates determined the surface tension of solid copper by balancing the force of surface tension in a very fine wire against an external load.' At that time we, in common with other early workers, assumed that grain boundary energy in a pure metal is very small in comparison to the energy of an external surface. Accordingly, we neglected the internal surface energy of the coarse-grained specimens. Since that time, experimental evidence has accumulated showing that grain boundary energy, far from being small, is generally about one-third of the energy of an external surface.2-4 This is sufficient to introduce a significant error into our determination. The differential equation governing equilibrium is: wdl - yds, + y*ds2 [I] rather than wdl = yds as originally written. w is the balancing force in dynes, 1 the length of the specimen, sl the external and s2, the internal surface area, y the copper/ copper vapor surface tension, and y* the grain boundary tension. Fortunately, we had made for another purpose a careful study of the size and shape of the grains, and found that the boundaries, with rare exceptions, traversed the specimens and were perpendicular to the wire axis. For this case, eq 1 leads to w = rry -(n) r2y* [2] where r is the wire radius and (n is the number of grains per unit length. A count of some twenty 5-mil wires indicated that - n became 80 & 10 after a short anneal near the melting point, and remained nearly constant for as long as 96 hr at temperature. An assumption of y* = 1/3y leads to a defining eauation for r: [31 The term in the brackets may be considered a correction factor applied to eq 11 of ref. 1. Upon applying this factor, the surface tension of solid copper at its melting point is found to be 1650 & 100 dynes per cm, rather than 1370 as previously reported.' The new temperature coefficient is —0.55 dynes per cm per "C. Grain boundary energy is more significant than surface energy to the physical metallurgist. It is evident from eq 2 that a series of experiments with wires of different grain size can lead to an evaluation of y*. The details of such an experiment are being worked out now. References 1 H. Udin, A. J. Shaler, and J. Wulff: The Surface Tension of Solid Copper. Trans. AIME, 185, 186-190; Journal of Metals (Feb. 1949) TP 25303. 2 G. L. C. Bailey and H. C. Watkins: Surface Energies in the System Solid Copper-Molten Lead. Proceedings Physical Society. (London) (1950) 36B, 350. 3 L. H. VanVlack: Inter granular Energy of Iron and Some Iron Alloys. Ph.D. Dissertation, Univ. of Chicago, Sept. 1950. 4 . P. Greenough: Grain Boundary Energies in Silver. R.A.E. Report, No. Met. 52. (May 1950) Fan-borough, Hants, England.

Jan 1, 1952

The Pinto Valley, Arizona, plant of Cities Service Company is one of the newest copper producers in the United States, having started production in 1975. It is located a few miles west of Miami, Arizona, on the site of the Castle Dome Mine, a World War II operation which was shut down and its mill later moved and renamed the Copper Cities plant. The Pinto Valley concentrator uses six 18 ft (5. 5 m) diameter by 21 ft (6.4 m) long, 4000 hp, single-stage ball mills, taking crushed ore from four 7 ft (2. 13 m) standard and eight 7 ft shorthead crushers. It has a design capacity of 40,000 stpd but has higher tonnage capability for an expanded concentrator. The copper porphyry-ore is mined by two 15 yd and one 20 yd shovels (11.5 and 15.3 cu m) and is transported to the primary crusher by 150-ton trucks. The dump pocket is relatively shallow (14 ft or 4. 27 m deep); and because of the width necessary for the 150-ton trucks, it was designed to use the ore itself instead of manganese steel as an abrasion- resistant lining, although a heavy steel cap protects the dump pocket top edge. The pocket has a capacity of 300 tons of ore. Water sprays under the dumping positions direct a fog toward the truck being dumped for excellent dust control. Breaking of oversize is done by a hydraulic impact breaker mounted on a hydraulically operated articulated arm situated at the side of the dump pocket. Again because of the shallow pocket, no splitter is used to protect the spider of the 60 in. by 89 in. Traylor gyratory crusher, which is equipped with a hydroset mechanism. Crushed ore at 8 in. (203 mm) drops into the 360 st surge chamber lined with AR plate and then is fed directly to the 60 in. (1.52 m) stock- pile conveyor by an 84 in. by 20 ft (2. 13 m by 6.1 m) four-speed apron feeder at a rate of up to 4000 stph. Early in 1977, Cities Service will replace the four -speed electric drive with a hydraulic pump and motor with infinitely variable speed. They are also studying the replacement of the apron feeder with an 8 ft wide (2.44 m) belt feeder similar to those at Similkameen and Palabora. Peak crushing capacity would then be increased to 5000 stph. The AR plate in the crushed ore pocket was installed in large, rectangular sheets which required much less embedded metal to hold it in place than would the more conventional, smaller arid square pieces of cast manganese steel. For duty in the crushed ore pocket, where wear is not severe, the AR plate is a satisfactory material. The new Palabora Figure-8 crusher also uses this design.

Jan 1, 1978

By Babbitts and Solder

G. w. Thompson,* Brooklyn, N. Y.—This subject has two aspects, neither of which can be ignored: these are the economic aspect and the technical aspect. Under ordinary conditions, economic law will take care of the conservation of tin. Under present conditions it seems desirable that economic law should still be permitted to operate as far as is practicable. It is true that this law operates rather slowly, and that under war conditions it cannot be depended upon to give our Government the supply it immediately needs. There should, therefore, be a designation of the essential industries by the Government, and tin should be supplied for those needs, letting the non-essential industries take what is left. At the same time, information ought to be forthcoming as to how tin can be conserved; with tin selling at 80 c. per pound, more or less, it is to the interest of every consumer to get the best information he can as to how he can save tin. Economic law would properly punish those who do not study their own interests in this way. I deprecate, therefore, any centralized socialistic effort toward avoiding penalties through failure to observe and obey economic law. In saying this, however, I am not unmindful that it is desirable for our Government to take such control of the tin situation as may be necessary to the prosecution of the war, practically regardless of the effect of such action upon individual industry, which should studiously seek to adjust itself to the new condition. The Government should promulgate such technical information as it can collect, showing how .tin can be conserved, and should urge upon every consumer the exercise of his common sense in self-protection. There is very little danger of any one attempting to hoard or corner tin, in the present state of the market. Most consumers will be glad to live from hand to mouth, covering their sales by purchases, or vice versa. As to the technical aspects: Tin and tin alloys are used to give certain practical and also certain artistic results. The practical factors are those involved in proper adhesion, continuity of surface, protection, the right degree of hardness, proper working qualities, etc. The artistic results are those that appeal purely to the eye or to our cultivated sense of what is desirable. There is no doubt that a great deal of tin could be saved if there were not a demand for certain pleasing effects. Row can this saving be brought about? The users of tin bearing alloys are not the only ones involved in this question. The manufacturers of solder and babbitt have for a long time sought to give certain appearances to their fabricated bars and ingots in order to make them more salable. The user of a solder is very apt to judge of its working qualities by the appearance of the bar; the same thing is true with regard to babbitts. Under ordinary conditions, manufacturers are justified in trying to

Jan 1, 1919

By Charles W. Goodale

In the course of the preparation of my paper on " The Occurrence and Treatment of the Argentiferous Manganese Ores of Tombstone District, Arizona" (Dam., xvii., 767), my attention was called to two patents which have been issued for the use of a diaphragm at the upper end of a Howell furnace, whose importance merits more than a passing reference. Mr. J. K. Pardee invented and first put into use in the Algon quin mill, at Philipsburg, Mon., in 1880, a ('new' and useful im provement in rotary ore-roasting furnaces," which was intended "to increase the capacity, effectiveness and working economies of such furnaces." The following description and accompanying figures are taken from the patent papers, dated December 21st, 1880: Fig. 1 is a side elevation of the feed-end of the Howell rotary furnace, with parts broken away, the better to exhibit my invention. Fig. 2 is an end elevation of the same. Fig. 3 is an end elevation of the same, showing a modification of my invention. In operating a furnace of this kind, of the capacity of one ton of ore an hour, it was found that for the best work the two fire-places (one at each end of the revolv ing cylinder) consumed about ten cords of wood every twenty-four hours, and that about twenty-fonr tons of silver-ore were introduced through the feed-pipe. It was also found that of the amount of ore, fully one-third did not go through the revolv ing cylinder, but went into the dust-chanibers about the feed-end of the furnace or cylinder, and this ore going into the dust-chambers was found not to be sufficiently chloridized for amalgamation, but had to be re-roasted. I then caused to be made, out of boiler-plate iron, a segment of a circle, the height of which was about one third of the diameter of. the cylinder or furnace, the circumference of the circle being smaller than the circumference of the furnace, so that about a half-inch space would be left between the plate and the furnace, when said plate or segment was in position. This segment or plate of iron was then fastened to the bottom of the feed pipe, as shown in the drawings, wherein A represents the revolving cylinder or furnace; B, the fire-place and dust-chambers at the feed-end of said furnace; C, the inclined feed-pipe, and D, the diaphragm, partition, or plate fixed within said furnace, A. With the diaphragm or plate, D, in the position shown, the furnace was run for about a month, and it was found that with the furnace in best working condition only four cords of wood every twenty-four hours were consumed, that no fire was required at the feed-end of the furnace, that not one-twelfth of the ore

Jan 1, 1890

The Enquirer of October 13, 1835 carried a letter signed "G," calling attention to the great number of Virginians who were leaving the state and to the lack of enterprise shown in not developing the ample natural resources available. He mentioned coal in particular and in closing said: "Besides the coal mines owned by individuals, the Black Heath company of colliers are carrying on extensive operations. Owing to the derangement of the currency, and the immense expenses incurred in boring and sinking new shafts, I understand that their dividends have not yet been so large, as they may be confidently expected in future.-Another company, under the title of the Midlothian Coal Mining Company, is now about being organized by the Messrs. Wooldridges of Chesterfield, for the purpose of establishing an extensive coal business. Having examined the lands embraced in the charter and the principles upon which the company is designed to be organized, I am persuaded that more productive stock can no where be found. The charter embraces a space nearly equal to a mile square, adjoining the mines of the Black Heath company, those of Mr. N. Mills, and those of Stone Henge, which space must contain coal of great thickness of excellent quality, as the strata of coal of those other mines pass through it; exhibiting a field so extensive, that centuries may elapse before it is exhausted. A shaft has been sunk on these lands, from which a very large quantity of the best coal is being raised. The terms of the charter require the Proprietors to sell one-half of these lands and mines, from the sale of which they will appropriate $100,000 as permanent capital, to purchase hands and engines, and to sink other shafts to work the property and thus going into operation with such decided advantages, as to produce a profit as great as a reasonable man should desire. Here is an opportunity for investing capital, which I think should satisfy the wishes of many Virginians who speak of emigrating. Will they not embrace it?-I have confined my remarks to the coal mines, because they are in the heart of our State, and their operations are familiar to many who can verify the statements. I might extend them to the other mineral treasures of our State; but if I do so, they must be reserved for another number, this being longer than I intended, and perhaps longer than you can conveniently find room for in your crowded columns. G." In January 1828 the Tuckahoe Canal Company was authorized to construct a canal along Tuckahoe Creek, from the James River up the stream about five miles; later this was amended to allow the use of the stream with a depth of water of two feet, no tow path was required, or provided: A toll of one cent per bushel was collected and the canal company made large profits. The service was so poor that in December 18, 1835, John G.,

Jan 1, 1942