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By John M. Dealy, Robert D. Pehlke

Values for interaction parameters in nonferrous systems, as calculated from published data, are tabulated and discussed. The influence of temperature on the parameter is derived and compared with the results of the literature study. Wagner's relationship between the interaction parameter and the self interaction coefficients is compared with the tabulated data. A problem which has been of considerable interest in the field of metallurgy is the prediction of the effect of one alloying element present in dilute concentration on the thermodynamic properties of another dilute alloying element. Ultimately, the prediction may be accomplished entirely from statistical mechanical considerations. At the present, however, the problem remains unsolved since liquid solution models which are simple enough for analytical treatment are inadequate for such purposes. Thus, we desire some means of organizing the information on dilute systems which will serve as a guide for further study on interactions in dilute alloys, and also provide a basis for the utilization of thermodynamic data in the engineering design of alloys.

Jan 1, 1963

By Robert Glass Cleland

THOUGH the rapid revival of the copper market in the early twenties solved the most serious of the company's immediate postwar difficulties, a much more fundamental, long-range problem still remained. Mining is not like farming: the earth does not bring forth a new crop of gold, silver, lead, zinc, oil, or copper at every harvest time. Metal taken from the ground does not spring up again from the old roots like perennial flowers in a garden, or find renewal in freshly sown seed. No ore body, whatever its size or richness, is too big or too rich to escape ultimate exhaustion. When the war closed in 1918, Phelps Dodge had been mining copper from Bisbee, Morenci, and Nacozari over periods varying in length from ten to nearly forty years. During much of that time, the company's production had run from fifty million to as high as two hundred million pounds a year. Even the greatest of mines had to respond in time to such a drain. High grade ore was already at a premium in Bisbee and Morenci. The Burro Mountain properties of New Mexico were a disappointment. Failing the acquisition of

Jan 1, 1952

By Paul Torrey

THE Northwestern Pennsylvania Oil Producers Association and the United States Geological Survey have cooperated in conducting a pre-liminary study of the character of the flood waters, the relationship of changes in concentration of the salts dissolved in these waters to ultimate flood-oil production, and the original association of oil and water in the Bradford field. Bradford has long been recognized as a dry-sand field. As a matter of fact, there had been little information available on the oil-field waters of northern Pennsylvania until this investigation was undertaken. THE BRADFORD SAND Practically all of the oil produced in the Bradford field comes from one horizon, generally known as the Third, or Bradford, sand. Originally, it was believed that the Bradford sand was equivalent to the Third sand of Venango County, Pennsylvania and the name "Third" unfortunately still persists, although shortly after the discovery of the Bradford pool Carll1 determined that there was a stratigraphic interval of approximately ;000 ft. between the two horizons. The Bradford sand, although varying considerably in thickness and lithology within local areas, is persistent throughout the field. It is of marine origin and, upon both paleontologi-cal and stratigraphic evidence, is regarded as a basal member of the Chemung formation.

Jan 1, 1927

By T. W. Guy

The increased moisture due to water-spraying for coal dust control is of interest even for mines from which the coal is to be wet-washed before screening, because in many cases wet coal dust materially de- 20-mesh X 0 sizes as pct ROM average ............................... 6.3 pct Range 2.3 to 9.5 pct 20-mesh X 0 sizes as pct 3/8 X 0 sizes average........'...................... 18.9 pct Range 12.7. to 23.9 pct creases the loading efficiency of men and equipment at the faces. It also causes a serious increase in the normal wear and deterioration of all equipment with which it comes in contact. It is important to the consumer if it increases his as-received moisture. No attempt will be made in this paper to cover the entire subject of water-spraying of coal for dust control. It will be confined to discussion and data on (I) percentages of dust in bituminous coals, (2) moisture increases due to spraying for dust control in mines or plants by methods which have proved satisfactory for periods of one to five or more years, and (3) a few suggestions for research. Size and Percentage or Coal Dust The U. S. Bureau of Mines1 classifies as coal dust all bituminous coal passing a 20-mesh sieve (0.0328 in. square opening). The percentage of such dust to be found in ROM coal, of course, varies widely with the characteristics of the seam, and with the methods used in the mining and in the preparation of the coal. ROM screen analyses of 12 U. S. coals selected at random from personal files given in Table I show: A few other screen analyses examined indicating 40 pct or more of 20-mesh X 0 dust in 3/8 in. X 0 sizes were not included because of uncertainty that they were representative. The number of results in Table I is not sufficient to give a reliable estimate of the average, or of the range to be expected, but it indicates that in every case the coal dust is a relatively large percentage of the total ROM coal, and, of course, a progressively larger percentage of resultants as the larger sizes are separated for marketing.

Jan 1, 1949

By Enrique Touceda

For a number of years prior to the world war, the firm of Geo. H. Thacher & Co., of Albany, N. Y., was engaged in the manufacture of marine and other gray-iron castings. At the outbreak of the war the firm decided to specialize in the manufacture of propeller wheels. It attacked the problem, therefore, from a foundry point of view, seeking to produce a casting that would be so accurate that no subsequent machining would be required on the blades, also from the point of view of the ship builder. There were two general methods of manufacture, the shortcomings of which have been freely acknowledged. In the sweep method, the nowel, or bottom half-mold, for each blade is swept up by a spindle beam and pitch race, while the top half-mold for each blade is built up individually. In the pattern method one individual blade, with the hub or hub portion, is mounted on a spindle and the individual blade mold formed, the pattern is then rotated on the spindle to the position for the next blade, etc. In rare cases wheels were made from a solid pattern. Owing to the cost of the pattern, its failure in many instances to be correctly made, and (when made of wood) its early and sure distortion the disadvantage of this pratctice is obvious, while metal patterns in most instances were prohibitive in cost. In these methods both green-sand and loam molding was practiced. The casting produced by either method can be considered only as a blank from which the propeller must be machined. The back surface of each blade must be chipped to the templet and through this procedure chipped to such accuracy as will be required for a static balance. Inasmuch as the work done by the machine tool is confined to the driving face of the blades, not only is perfection most difficult, but corrosion will be greater because of the removal of the dense skin of the casting and the local strains set up by the pneumatic tool in chipping. To produce a finished 9-ft. propeller for a Navy destroyer required from 8 to 21 days of foundry work and about the same length of time for the machining. Through the use of the Thacher process, only as many hours are required, besides it is possible to produce a finished casting in perfect conformity with any particular propeller-wheel design.

Jan 1, 1922

By Enrique Touceda

For a number of years prior to the world war, the firm of Geo. H. Thacher & Co., of Albany, N. Y., was engaged in the manufacture of marine and other gray-iron castings. At the outbreak of the war the firm decided to specialize in the manufacture of propeller wheels. It attacked the problem, therefore, from a foundry point of view, seeking to produce a casting that would be so accurate that no subsequent machining would be required on the blades, also from the point of view of the ship builder. There were two general methods of manufacture, the shortcomings of which have been freely acknowledged. In the sweep method, the nowel, or bottom half-mold, for each blade is swept up by a spindle beam and pitch race, while the top half-mold for each blade is built up individually. In the pattern method one individual blade, with the hub or hub portion, is mounted on a spindle and the individual blade mold formed, the pattern is then rotated on the spindle to the position for the next blade, etc. In rare cases wheels were made from a solid pattern. Owing to the cost of the pattern, its failure in many instances to be correctly made, and (when made of wood) its early and sure distortion the disadvantage of this pratctice is obvious, while metal patterns in most instances were prohibitive in cost. In these methods both green-sand and loam molding was practiced. The casting produced by either method can be considered only as a blank from which the propeller must be machined. The back surface of each blade must be chipped to the templet and through this procedure chipped to such accuracy as will be required for a static balance. Inasmuch as the work done by the machine tool is confined to the driving face of the blades, not only is perfection most difficult, but corrosion will be greater because of the removal of the dense skin of the casting and the local strains set up by the pneumatic tool in chipping. To produce a finished 9-ft. propeller for a Navy destroyer required from 8 to 21 days of foundry work and about the same length of time for the machining. Through the use of the Thacher process, only as many hours are required, besides it is possible to produce a finished casting in perfect conformity with any particular propeller-wheel design.

Jan 1, 1922

By Lewis Carroll

AS he contemplates the numerous good things the hard-working committees have evolved for the 140th Meeting of the Institute, the Editor knows just how the walrus felt when he uttered his memorable, if somewhat lugubrious lines. For there are the Annual Reception and Dinner at the Commodore, 'the Gold Supply Symposium, the luncheons, general and special, and the Annual Institute of Metals Lecture, a Round Table on Iron Ore and a wonderful Informal Dance at the Grand Central Art, Gallery, substantial general sessions, a Smoker-and many other things. -Old, friends and new, reminiscences and confidential chats, horizons pushed back by new information and adjusted perspectives, courage revived and ambitions stimulated-one with a flair for the modernistic might make something-or nothing-of the kaleidoscopic preview 'of the coming Annual Meeting.

Jan 1, 1931

By George Macready

TRINIDAD, British West Indies, is an island near the north coast of South America, situated between latitudes 10° and 11° N:, and. opposite the numerous outlets of the Orinoco River Delta. It is separated from Venezuela by the Gulf of Paria (salt, water) and straits over 5 mi. (8 km.) wide. The area of the island is approximately 1750 sq. mi. (453,- . 250 hectares) and the population is approximately 400,000. The climate is tropical with an annual rainfall of from 45 to 60 in. (114 to 152 cm.). The oil fields consist of several units, or fields, located in the southern half of the island. Approximately 90 per cent. of the total production has been yielded by fields situated within 7 mi: (11.3 km.) of the famous asphalt lake and on the southwest peninsula. The most important producing fields, or units, are the following, which are shown on the accompanying map: Brighton, or Pitch Lake Field, operated by the Trinidad Lake Petroleum Co., Ltd., is situated beside the famous Pitch Lake; it, even encroaches on the lake. Vessigny Field, operated by the Trinidad Lake Petroleum Co., Ltd., is situated 2 mi. (3.2 km.) south of Pitch Lake. Lot One Field, operated by the Petroleum Development Co., Ltd., the United British Oilfields of Trinidad, Ltd., and Stollmeyer, Ltd., is situated 3 mi. south of Pitch Lake upon Lot One of Morne 1'Enfer Forest Reserve and adjoining properties. Parry Lands Field, operated by the United British Oilfields of Trinidad, Ltd., and the Petroleum Development Co., Ltd., is situated 3;2 mi. south of Pitch Lake on Lot Three of Morne l'Enfer Forest Reserve and adjoining properties. Point Fortin Field, operated by the United British Oilfields of Trinidad, Ltd., is situated at Point Fortin, 6 mi. southwest of Pitch Lake. Fyzabad Field, operated by Trinidad Leaseholds, Ltd., is situated several miles southwest of Fyzabad Village and 6 mi. south-southeast of Pitch Lake. Barracpore Field, operated by Trinidad Leaseholds, Ltd., is situated several miles south of. San Fernando and 15 mi. (24.14 km.) east of Pitch Lake.

Jan 9, 1920

By Howard L. Hartman

There is reason to believe that ventilation systems so far devised for use with continuous mining machines fall far short of success. This is vividly demonstrated to anyone who has observed in a continuous miner section the localized ignitions of pockets of gas and the generation of dense clouds of dust by the cutting head of the machine. The alarming frequency with which major ignitions and disasters continue to occur in modern mechanical mining and the rise in incidence of pneumoconiosis serve as reminders that our ventilation systems are far from achieving the ultimate in providing protection from either short-term explosions or long- term dust diseases, both of which take lives. Human safety is the main concern in ventilation. But in this day of high-priced labor, let us not forget human comfort, either, for this is a major factor in motivation toward high productivity. The failure or inadequacy of most mine ventilation systems in providing the kind of working conditions at the face that are conducive to productive as well as safe operation is an indictment of our environ- mental control program in mining generally.

Jan 3, 1962

By E. H. Crabtree

This paper traces the experimental and pilot plant work completed by the authors since 1939 including the various methods which have been developed in applying coarse activated carbon to cyanidation. The methods and results developed by the authors in desorbing gold and silver from carbons are given and the possibilities for the re-use of the desorbed carbons are discussed

Jan 1, 1950

By AIME AIME

LOCAL COMMITTEES. GENERAL RECEPTION COMMITTEE.-Mr. and Mrs. H. S. Chamberlain, Mr. and Mrs. J. T. Lupton, Mr. and Mrs. T. H Lasley, Mr. and Mrs. R. S. Faxon, Mr. and Mrs. H. Clay Evans, Mr. and Mrs. C. E. James, Mr. and Mrs. B. F. Thomas, Air. and Mrs. H. S. Probasco, Mr. and Mrs. W. M. Lasley, Mr. and Mrs. L. W. Llewellyn, Mr. and Airs. T. G. Montague, Mr. and Mrs. E. B. Thomasson, Mr. and Mrs. C. F. Milburn, Mr. and Mrs. C. A. Raht, Mr. and Mrs. C. C. Notting¬ham, Mr. and Airs. Z. C. Patten, Mr. and Mrs. Willard Warner, Mr. and Mrs. S. R. Read, Mr. and Mrs. Carl White, Mr. and Mrs. M. M. Allison, Air. and Mrs. C. E. Buck, Mr. and Airs. H. F. Temple, Air. and Mrs. M. M. Hedges, Mr. and Airs. X. Wheeler, Mr. and Airs. John A. Patten, Air. and Airs. N. T. Montague, Mr. and Mrs. R. H. Williams, Mr. and Mrs. T. R. Preston, Mr. and Airs. Morrow Chamberlain, Mr. and Airs. T. C. Thompson, Mr. and Airs. T. L. Montague, Mr. and Mrs. O. L. Hurlbut, Air. and Mrs. C. A. Lyerly, Mr. and Mrs. Garnett Andrews, Air. and Mrs. M. B. Ochs, Mr. and Airs. Webster James, Mr. and Mrs. D. P. Montague, Mr. and Mrs. Z. C. Patten, Jr., Mr. and Mrs. W. A. Sadd, Mr. and Mrs. J. B. Pound, Air. and Mrs. George D. Lancaster, Air. and Airs. J. F. Johnston, Mr. and Mrs. R. W. Barr, Air. acrd Mrs. W. B. Davis, Mr. and Airs. Douglas Baxter, Air. and Mrs. W. R. Crabtree, Mr. and Mrs. Lewis M. Coleman, Mr. and Mrs. Newell Sanders, Mr. and Mrs. E. Y. Chapin, Mr. and Mrs. W: B. Riddell,. Mr. and Mrs. J. B. Frazier, Mr. and Mrs. John A. Moon, Mr. and Mrs. C. D. Mitchell, Dr. and Airs. J. H. Race, Mr. and Airs. A. W. Chambliss, Mr. and Mrs. J. P. Smartt, Mr. and Mrs. J. F. Tarwater, Mr. and Mrs. L. D. Drewry, Capt. and Mrs. A. B. Putnam, Mrs. Minnie C. Ewing, Mr. G. F. Meehan, Mr. Sam S. Gerstle, Mr. P. A. Brawner, Mr. C. M. Preston, Air. George M. Guild, Mr. L. M. Mansfield, Dr. J. W. Johnson, Dr. J. AI. Hogshead. EXECUTIVE COMMITTEE.-H. S. Chamberlain, Chairman; H. S. Probasco, C. M. Preston, H. Clay Evans, J. T. Lupton, M. B. Ochs, C. C. Nottingham, Al. Al. Alli¬son, R. S. Faxon, C. E. James, C. A. Raht. EXCURSION TO CHICKAMAUGA PARK.-T. C. Thompson, Chairman; B. F. Thomas, G. F. Meehan, Morrow Chamberlain, W. J. Bass, J. K. McGoodwin. EXCURSION TO HALES BAR LOCK AND DAM.-R. H. Williams, Chairman; John A. Patten, Newell Sanders, George M. Guild, Capt. A. B. Putnam. EXCURSION TO ROCK-WOOD.-F. H. Clymer, Chairman; T. L. Brown, T. A. Wright, J. P. Tarwater, T. L. Peterman. INSTITUTE HEADQUARTERS.-The Hotel Patten. THE first session, held Thursday evening, Oct. 1, in the Banquet Hall of the Hotel Patten, was called to order by Capt. H. S. Chamberlain, Chairman of the Local Committee, who, in behalf of the city of Chattanooga, extended a hearty welcome to the members and guests of the Institute.

Nov 1, 1908

By O. W. Walvoord

ONE particular plant has been chosen to illustrate the various factors in mill design. The problems are general in nature and with various modifications are met in the design of most milling plants. Literature on modern mill design is not extensive and certainly has not kept pace with the rapid advancement in the art of ore beneficiation. Much remains to be investigated, and continued vigilance is required to give the operator and the metallurgist the best layout to meet the industry's changing requirements. The Humboldt project, a joint venture of the Cleveland-Cliffs Iron Co. and the Ford Motor Co., involves an iron ore flotation plant near the town of Humboldt, on the Marquette range of the Michigan Upper Peninsula. A crushing plant, designed for an ultimate capacity of 720 long tons per hr, is followed by a first mill unit of 70 long tons per hr. Future mill units are planned to bring the total mill capacity to 5000 long tons per 24 hr.

Jan 1, 1954

By Francis Lucas

ANY metal which contains even a small percentage of aluminum possesses certain peculiarities of appearance and properties which are exhibited both when the metal is melted and after it solidifies. Pure aluminum, or an alloy containing a small proportion of aluminum, can be melted without flux-except for a layer of charcoal-because a film of aluminum oxide and metal forms at the surface of melted aluminum. Although very thin, this film is air-proof, and it prevents the metal underneath from oxidizing. This oxidized film does not move easily on account of its toughness and high surface tension. One very important point in connection with this process of still casting has not been strongly enough stressed, namely, that the same kind of surface film with the same peculiarities forms over the surface of all melted alloys that contain even a small proportion of aluminum. Experienced foundrymen know how desirable it is to cast aluminum under its "skin" or-under the surface of the film which tends to remain still. In the case of red copper, when in fusion, the surface shows pure copper only. This is due to the fact that liquid copper constantly absorbs the copper oxide which forms on the surface. By closely examining melting copper the oxide can be seen dissolving in the bath, and going into solution just as pulverized sugar dissolves in water. When copper is cast in the open, either in wire bars or cakes, the surface of metal exposed to the air is covered by a film of black, oxide that cannot be absorbed by the metal.

Jan 1, 1927

By J. Kinkead, R. M. Sherman, E. M. Frizzel

A recent research study performed under US Bureau of Mines Contract No. J0199088 "Modular Irrigation Equipment for Reclaimed Strip Mined Lands" investigated the feasibility of irrigation as a reclamation tool in the arid and semi-arid regions of the Western United States. Review of mined land characteristics, evaluation of irrigation systems, and assistance from the mining industry resulted in the design of two strategies for the implementation of reclamation irrigation using solid set systems. It is not the intent of this paper to suggest the generalizations made on the basis of a six state area can extend to the design of an irrigation system for a specific mine site. The purpose is to present two irrigation strategies that may be implemented with solid set irrigation in this six state area. The reader should note that the following is the result of research and, therefore, original concepts were presented. The ultimate validity of these concepts will be determined by future field tests.

Jan 1, 1983

By W. E. Pugh

The object of the following is to discuss a few of the problems encountered in the practical field application of reflection seismology. Very little has been published on this phase of the work and it is to be hoped that discussions will be presented by many seismologists who have met with these problems in the field. No attempt will be made to discuss the general principles of reflection prospecting, nor to outline the general field procedure. These phases have been presented more or less in detail in previous publications1 while economy of space and time prevents their being repeated or amended here. If, in the following pages, some criticism is offered of those who have already given their time and efforts to present valuable papers on reflection shooting, we trust that it will be accepted in the constructive light under which it is offered. We do not wish to give the impression that the following paragraphs represent ultimate achievement in field procedure; they are presented more to illustrate methods we have found satisfactory thus far. We believe that the following three subjects are inexorably linked with the continued future successes and more widespread use of the reflection method which, at the present time, is the most

Jan 1, 1934

By J. B. Scott, J. S. Nelson, G. H. Kruse, W. S. Johnson, K. L. Zerneke

The economics of pressure tunnel design emphasize the utmost utilization of the least expensive pressure-resisting material available, namely, the rock surrounding the tunnel. A major difficulty in the design is the problem of transferring internal hydraulic pressure to the rock through a tunnel lining or membrane provided to maintain watertight conditions. The lining is necessary not only to prevent water loss, but to prevent the diffusion of water at high pressure through joints and fractures beyond the confines of the tunnel, an occurrence which could ultimately affect the stability of the rock mass through which the tunnel passes. Because of its toughness and ability to bridge localized areas of weakness, steel is used for a lining material whenever high internal pressures are involved. The steel lining is coupled to the surrounding rock mass through an annular ring of concrete backfill. It is paradoxical that the steel lining, needed primarily to assure water tightness, must of necessity be incorporated into the structure as a major pressure-resisting component, not to augment the bearing capacity of the concrete and rock, but to limit the strain for the safety and preservation of the steel lining itself. With the deformation modulus of the steel so much greater than that of the rock, the liner approaches its yield strength before the load capacity of the rock can be fully mobilized. An economical determination of plate thickness for steel liners is therefore dependent upon measurement of the properties of the surround-

Jan 1, 1970

By J. E. Johnson

At the Cleveland meeting of the Institute in October, 1912, I had the honor to present a paper outlining the conditions surrounding the charcoal iron industry…

Jan 1, 1915

By Frederick K. Allgaier

As part of an ongoing research program, the Bureau of Mines, U.S. Department of the Interior, is monitoring surface subsidence over six longwall panels at three Utah coal mines. These sites are characterized by mining depths of 244 to 610 meters (800 to 2,000 ft .), thick and massive sandstone layers in the overburden strata, multiple seam mining, extraction heights of approximately 1.8 to 3 meters (6 to 10 ft.), and rugged surface topography. Maximum subsidence, angle of draw, timing relative to mining, horizontal strain, and rate of subsidence development are being determined and correlated with mining and geologic variables. Results to date indicate the maximum vertical subsidence over the monitored panels ranges from 0.6 to 0.9 meters (2 to 3 ft.). The major factors controlling the amount of subsidence are the panel dimensions and the status of adjacent panel mining. Only minor surface cracking at the panel ends was evident at any of the sites. In all cases, there was a time lag of several months between the start of mining and subsidence at the surface. As subsequent panels are monitored and additional data become available, better estimates of the effect of various site characteristics on the subsidence will be possible. Ultimately, improved prediction capabilities will allow mine operators in the West to evaluate the potential for subsidence-related damage which could affect the current or future land use above the mine.

Jan 1, 1982

By J. M. Bugbee

THE engineer and the conservationist agree that effective water drive is the desirable reservoir production mechanism. Water drive may result either from the expansion of edge water, the reservoir water bordering an oil pool, or from the artesian flow of edge water from the outcrop. Thus, the extent of the reservoir has an important bearing upon both the rate and the ultimate quantity of water influx to an oil pool. Lens-type reservoirs are generally recognizable, but the complete structure of the more important domal types, having possible limitations from crestal and synclinal faulting, is not well understood. The delineation from cores, electrical logs and exploitation phenomena of the crestal portions of reservoirs is increasingly exact. This paper suggests that inference from these factual pictures, combined with the scattered well and geophysical data of the synclines and with consideration of the dynamics of structural formation, may be applied to solving the complete geologic structure. Since faulting on the domes and in the synclines may effectively seal and thus limit the size of a reservoir and bar additional water influx, consideration of geologic structure and its possible effects is essential to complete analysis and prediction of reservoir performance.

Jan 1, 1942

By R. W. Waterfill

MANY existing ore deposits of valuable metals have been worked out in their upper surface levels and the continued productivity of these mines is dependent on their extension to greater depths in the earth. The maximum depths at present reached are about 6000 to 8000 ft. below the surface, with no evidence of an impoverished ore vein. These mines are widely distributed; some of the best known are in South Africa, Brazil, India and in the western sections of the United States. Among the factors which increase the difficulty of working these mines at increasing depths are hoisting, rock pressure and temperature. The manner and effectiveness with which these problems are met will, no doubt, determine in a large measure the ultimate depths to which any mine can be profitably worked. The most critical of these three factors at present is the increase in temperature with depth. The high temperature and humidity in many of these mines at present is severely detrimental to the health of the workers and greatly hampers their efficiency. Some have almost reached a condition in which the human system cannot survive. The problems involved in the cooling and ventilation of mines have all been ably analyzed and presented in previous articles. For this reason, only a resume of conditions affecting the cooling and conditioning of deep and hot mines will be given in this paper before attention is directed to possible methods of improving atmospheric conditions in the working levels.

Jan 1, 1929