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CONTENTS PAGE SOUTHWARD, GLENN B.-Coal Mining by the V System. Discussed by Glenn B. Southward, Howard N. Eavenson, Edward B. Raiguel, Thomas de Venny, J.. J. Rutledge, Graham Bright 1 ARMS, RAY W.-Dry Cleaning of Coal. Discussed by Ray W. Arms, S. A. Taylor, Howard N. Eavenson, W. R. Crane, F. F. Jorgenson, G. R. Delamater. 6 EAVENSON, HOWARD N.-Data About Labor Employed in Various Bituminous Coal Mines. Discussed by Howard N. Eavenson, George H. Ashley, E. A. Holbrook, S. A. Taylor, R. V. Norris 14 Coal Mining by the V System Discussion of the paper of GLENN B. SOUTHWARD presented at the New York Meeting, February, 1924, and issued as Paper No. 1300-C, with MINING AND METALLURGY, February, 1924. MEMBER.-How do you pay your men for loading? GLENN B. SOUTHWARD.-Everything is on time basis. MEMBER.-How many men do you have loading across one of the diagonal faces? GLENN B. SOUTHWARD.-From four to five, depending on the length of the face. Our loaders are so arranged that each will give about twenty-five tons per loader a day. MEMBER.-How much timber do you use? GLENN B. SOUTHWARD.-A little more than will be used in room-and-pillar work, but not a great deal more. We have not attempted to recover much of our timber. MEMBER.-IS the mine union or non-union? GLENN B. SOUTHWARD.-Non-union. HOWARD N. EAVENSON, Pittsburgh, Pa.-I went .through that mine some weeks ago, and think that the author has been very conservative in his statements about the amount of loadings, etc. EDWARD B. RAIGUEL, Huntington, W. Va. (written discussion).¬Page 7 shows 60 men employed in day and night shifts, inside the mine, producing 750 tons per day. Let us reduce these figures to a man-hour basis, for comparison with Mr. Eavenson's figures on West Virginia mines, as follows:

Jan 6, 1924

By W. E. Hale, G. J. S. Govett

An orientation survey was conducted over a known disseminated copper deposit and a Au-Cu vein deposit and employed geological, geophysical, and geochemical methods. Geochemical techniques proved the most effective and economical means of locating and defining areas underlain by these types of mineralization. Six additional, widely separated occurrences were also investigated and mineralization was confirmed by determination of cold-extractable copper in stream sediments. The length of anomalous drainage varies from several to 16 km and depends on the type and tenor of mineralization. Despite generally marked relief and extreme physical and chemical weathering, cold-extractable copper anomalies in soils appear to reflect closely variations in the ore mineral content of immediately underlying rocks. Threshold values vary with local geological conditions and type and grade of mineralization. Significant thresholds in stream sediments are about 65 ppm and 10 ppm for cold-extractable copper in disseminated and vein copper occurrences respectively. Similar differences are encountered in soils. This necessitates the use of a scale of threshold values at progressive stages in each exploration program. Dis-seminated copper occurrences are presently the major source of mineral production m the Philippines. Much potentially productive ground remains to be investigated and applied geochemistry appears to offer the best available approach. The Institute of Applied Geology (I.A.G.), a joint project sponsored by the University of the Philippines, the Philippine Bureau of Mines and the United Nations Development Program (Special Fund) undertook during 1965-66 a number of field projects in Northern Luzon Island (Fig. 1). These field operations were of a two-fold nature and involved both orientation and exploration. During approximately six weeks, an orientation survey, involving geological mapping, geophysical surveying and geochemical prospecting, was conducted over a partly developed, disseminated copper deposit at Santo Nino (Fig. 1). This study demonstrated the economic and technical feasibility of geochemical ptospecting, relative to the other methods tested, for the location and delineation of a typical disseminated copper occurrence characteristic of those that represent the major source of metal in the Philippines.' Geochemical techniques, similar to those tested at Santo Nino, were then applied in a second orientation study of a vein occurrence at Suyoc (Fig. 1). The results of these two orientation studies suggest that, in reconnaissance work in this region, stream sediment analyses, combined with the determination of pH in the same streams, can be used to indicate areas underlain by rock containing anomalous concentrations of copper, whether it occurs in the large tonnage, low grade, disseminated deposits or in the comparatively small tonnage, higher grade, gold vein occurrences. Furthermore, the orientation surveys demonstrate that soil sampling and analysis serve effectively to outline more closely the mineralized zones within the generally anomalous areas identified from the stream reconnaissance. To further test the methods selected from the two earlier trials, six additional, widely separated prospects were investigated. The geological and geochem-

Jan 1, 1970

By C. A. Zapffe

BOTH the foundryman and the theoretical metallurgist are now generally agreed that the anomalous "rising" or "bleeding" of certain ferrous castings of killed metal is primarily attributable to hydrogen. How and why the phenomenon occurs, however, have not been made clear. The following discussion is intended to harmonize foundry experience with metallurgical theory so that the foundryman may possibly improve his ability to prognosticate whether a certain casting may bleed or not. BLEEDING, RISING, AND PIPING The "rising" to be discussed here is not to be confused with the action in rimming ingots as a result of the carbon-oxygen reaction, although a conclusion will be drawn that may apply to the art of controlling the rimming action. Only killed metal is considered, which includes both steels and irons. In Fig. I, three killed, chill-cast ingots are shown: a porous ingot whose evolution of gas during late stages of solidification has ejected metal through the top; an ingot in which moderate gas evolution during solidification has lifted the mushy central metal, i.e., it has "risen"; and, third, a sound ingot with good piping characteristics. The first type is referred to as "bleeding," and generally infers that a solid skin had first formed through which the liquid metal later erupted. There is no fundamental distinction between bleeding and rising in reference to killed metal.* POROSITY Hydrogen appears as a cause of bleeding because the gas evolution simultaneously leaves a porosity of a type traceable to hydrogen. Twenty years ago, Melmoth1 noted that killed steel that rose unexpectedly in the mold, if returned while liquid to the furnace and heated further under a reducing lime slag, would again rise in the mold; but that if the ingot were allowed to solidify and was then remelted no rising occurred. A critical quantity of the responsible gas is therefore removed by the rising action. Melmoth associated rising with high silicon (0.7 to 0.9 per cent) and concluded that silicon increased gas absorption. Because silicon is a strong deoxidizer, oxygen must, therefore, be eliminated from consideration of the three common gases in steel-oxygen, nitrogen, and hydrogen. Butterworth2 later decided that pinhole porosity was caused by gases dissolved in the metal and that hydrogen was obtained from steam in the mold. Allen's classical work on copper castings,3 soon followed by

Jan 1, 1942

By N. A. Stockett

SOUTHEAST Missouri is the largest and oldest lead-producing district in the United States. For the year 1941, the statistical picture of pig-lead production, stated in short tons (partly estimated by the Engineering and Mining Journal) is as follows. [Tons World production 2,000,000 United States production 460.000 Southeast Missouri production 242,000] The consumption of primary lead in the United States in 1941 was approximately 900,000 tons, or almost double the country's production. The largest previous year's consumption in the United States was 718,000 tons, in 1926. The largest quantities of lead are used for cable sheathing, storage batteries and white lead. During 1941 tetraethyl lead for auto and aviation gasoline consumed 50,000 tons of lead. The entire lead production of Southeast Missouri is now mined by the St. Joseph Lead Co., whose dominant position as the largest producer in the United States of lead directly from ores is best shown by the fact that in 1941 it produced approximately 31 per cent of the lead production of the United States from its mines in southeast Missouri, where 22,000 tons of ore, averag¬ing over 3.00 per cent lead, is mined per working day. It is known that lead was mined at Mine La Motte, Madison County, Missouri, by Renault in 1723. Other white men and Indians probably did some mining prior to that time. Since 1865, the recorded production to Jan. 1, 1942, shows that the St. Joseph Lead Co. and the various other companies that have operated in St. Francois County mined lead ore, which, after milling and smelting losses produced 5,00,000 short tons of pig lead. About 95 per cent of the present lead production of Southeast Missouri is mined in St. Francois County. The northern part of this area is 60 miles south of St. Louis. The remainder of the lead is obtained at Mine La Motte, about 25 miles southeast from the center of the producing area in St. Francois County. PROSPECTING In this district, most of the ore is discovered by surface and underground diamond drills and by prospect drilling underground with rock drills. Each 2-ft. length of the cuttings from these Jackhamer prospect holes is assayed for lead. These holes are marked and the records are entered on maps. It has been found that close drilling--100-ft. centers of holes, and sometimes less-is necessary in order to locate most of the smaller commercial ore bodies, many of which previously had been missed by drilling the areas with holes spaced 200-ft. centers or more.

Jan 1, 1943

By W. A. Sweet

The furnace I am now about to describe was designed to obtain and maintain very high temperature. Knowing the cost of the gas furnace that was in successful operation here and abroad, I approached the subject with some misgivings as to my ability to attain anything like success, or even to reach a point of advancement. There seemed to be a field for a furnace of moderate cost for small mills, or where a particular heat was wanted, but the work was not enough to warrant the outlay necessary to build any gas furnace yet brought before the public. The section, Plate V, represents the furnace as I now build it for

By W. A. Sweet

THE furnace I am now about to describe was designed to obtain and maintain very high temperature. Knowing the cost of the gas furnace that was in successful operation here and abroad, I approached the subject with some misgivings as to my ability to attain anything like success, or even to reach a point of advancement. There seemed to be a field for a furnace of moderate cost for small mills, or where a particular heat was wanted, but the work was not enough to warrant the outlay necessary to build any gas furnace yet brought before the public. The section, Plate V, represents the furnace as I now build it for

Jan 1, 1875

By Gen-Hua Shi

The deformation of a discontinuous rock is a sum of individual translations, rotations, and strains of the component blocks. These produce opening and slip between blocks along the discontinuities. Rather than attempting to analyze such deformations with a mathematical model representing the geometric and stress/strain properties of all points, for the back-calculation of observed displacements we have produced a novel approach to solve the inverse problem. Using a field of displacement measurements and a map of the system of discontinuities, the method, determines the intrablock and interblock motions by a least squares formulation. In this brief paper we address only two- dimensional formulations. However, computer codes have also been developed for three dimensional problems.

Jan 1, 1984

By W. Wanjokow, H. O. Hofman

In the metallurgical treatment of most metallic sulphides it is usually necessary to carry on a roasting-operation. In some cases the raw ore will have to be roasted; in others the intermediary product, matte, produced in smelting the ore; again, both ore and matte may have to be subjected to oxidation at elevated temperatures. Most metallic sulphides, when given an oxidizing-roast, pass through the state of sulphate before they are converted into oxides. All metallic sulphates are completely decomposed by heat, with the exception of those of lead and bismuth, but the temperatures at which decompositions take place vary with the metals. Some metallic sulphates are converted directly into oxides, others first form basic salts. Alkali-earth sulphates show a behavior similar to that of metallic sulphates, while alkali sulphates do not part with their sulphur trioxide even at elevated roasting-temperatures. The older data on the decomposition of metallic sulphates by heat are only approximations. Thus Kerl' gives the order in which metallic sulphates are decomposed with increasing temperatures as (Ag2, Fe, Cu, Zn, Ni, Co, Mn, Pb) SO,. More recent statenlents give definite temperatures and modify the formerly accepted order of decomposition. But the temperatures given by various observers do not agree. The reasons for this are to be found mainly in the method and manner of carrying out experiments. Four methods have been used: 1. Heating in an evacuated tube; 2, heating in a tube closed at one end, without air-cur-

Jan 1, 1913

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

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

Jan 1, 1944

By T. Johnston, B. Cox

The results of oxidation and corrosion experiments on niobium in oxygen and steam at temperatures of 350° to 650°C, and in dilute sulphate solutions at 300°C are presented. The oxidation of niobium in oxygen can be explained in terms of a pre-transition period, which obeys an approximately parabolic rate law, and a post-transition period in which a more rapid linear rate is partially stifled by restriction of the gas flow due to the gvowth of the porous outer film. Due to changes in the porosity of the outer layers the restriction presented by the porous outel. film attains a limiting value. Subsequent oxidation obeys a linear rate law and shows an almost linear dependence of the rate on gas pressure. liltimately a second failure of the protective film may take place leading to a further acceleration in the oxidation rate. In water vapor the oxidation of niobium follows a parabolic rate law and does not show a transition to linear kinetics. The higher oxide, Nba05, was usually absent from the NbO/NbO2 film which was formed. The addition of a small partial pressure of oxygen to the water vapo3, resulted in accelerated oxidation according to the normal kinetics for oxidation in oxygen. The oxygen reacted preferentially with the niobium, and the protective oxide film was reformed when all the oxygen had been consumed. This behavior supports the theory that nucleation of Nb205 on the surface of the protective NbO/NbO2 film is the cause of the accelerated oxidation. After oxidation in steam at high-pressure Nb2Os was found in the protective film. The mode of formation of Nb2O5 under these conditions did not produce a change in kinetics, but was thought to explain the comparatively large dependence on pressure of the oxidation rate. The kinetics of oxidation in oxygenated aqueous solutions at 300°C were similar to those for oxidation in oxygen. A penetrating attack on niobium sheet may be related to the second breakaway observed by some investigators of oxidation in oxygen.

Jan 1, 1963

By H. F. Yancy

PooR results in coal washing and in ore concentration are sometimes attributed to the shape of the particles in the feed. It is well known that the shape of a particle influences its rate of fall in water. This is evidenced by the value of the constant C in the Rittinger equation for the velocity V of settling in water, V = C-D(d- z ), where C has the following values: 2.73 for roundish grains, 2.37 for long grains and 1.92 for flat grains. This report, which is based upon data obtained during the course of coal-washing investigations conducted by the U. S. Bureau of Mines in cooperation with the College of Mines of the University of Washington, gives the results of a method or procedure of screening in which the particles are separated into three shapes and shows the deportment of these shapes when coal is treated on a coal-washing table. The method consisted in first screening the coal with Tyler standard square-hole sieves, followed by screening tests of each of these products with screens of rectangular opening. For this purpose Tyler "Ton-Cap" screens were used; each square-hole product was subsequently sized with two Ton-Cap sieves so selected that their shortest dimensions were approximately 75 and 50 per cent., respectively, of the opening of the square-mesh sieves. For example: A product which is through 8 mesh (0.093 in.) and on 10 mesh (0.065 in.) is screened on slotted sieves which have openings 75 and 50 per cent. of the 0.065-in. opening in one direction and an opening of not less than 0.065 in. in the other direction. For convenience in discussion, the particles retained on the first slotted screen are termed "cubical"; those retained on the second slotted screen are termed "prismatic" and those passing the second screen are called "flat." (See Fig. 1.) The square-mesh screens separate particles according to two dimensions, length and breadth; the slotted screens divide them further according to the third dimension, or thickness. Prismatic particles have a mass of about two-thirds, and flat particles of about one-half, that of cubical particles of the same square-mesh size. The screen-

Jan 1, 1931

By Norman Carmichael, John Kiddie

The problem of transportation in the Clifton-Morenci district of Arizona has been one of peculiar difficulty and consequently has been an important factor in the cost of mining and treating the ores produced. From the crude beginning made over 50 years ago, many changes have been necessary to keep pace with the increased output of copper. A heavy-duty haulage system has developed on the original 20-in. track gage to meet the existent metal-mine conditions. Topography The transportation difficulties of this district may be readily appreciated from the relief map shown in Fig. 1. The northern half of the district is high mountainous country and there is a general but irregular drop toward the southern part, where the country, although still rugged, is in reality a great sloping plain. This is cut by numerous ravines from which the waters, in the rainy season, discharge into the channel of the San Francisco River. A chasm, 1000 ft. deep, has been eroded through the center of the district by Chase Creek, which is flanked by high irregular mountain masses, notably Copper Mountain, American Mountain, Coronado Mountain, and Markeen Mountain. The latter rises 2300 ft. above the bed of the creek, The San Francisco River has also cut a deep channel, though it is somewhat broader than Chase Creek. Eagle Creek traverses the extreme southwest portion of the area, where it has carved picturesquely through vast volcanic flows. Faulting has left its mark upon the topography of the district by adding to the irregularities caused by erosion. Strong faults occur at the Coro-

Jan 1, 1924

J. S. Unger,* Pittsburgh, Pa. (written discussion?).-I heartily agree with the author's suggestion, near the close of the paper, that greater uniformity in the making and use of brick is desirable. The effect of the manner of laying the brick, the mortar or cement used, the necessity of standardizing the shapes, the elimination of irregular or poorly designed brick, and the necessity for uniform operating conditions were pointed out by me some years ago. Many factors influence the quality of firebricks. The following figures obtained from bricks during their making or after completion show the need for greater uniformity in their quality. These results were obtained from regular commercial bricks, shipped to the consumer. In many cases the samples were from the same car load.

Jan 11, 1919

By R. W. Raymond

THE important question of the metallurgical value of the coals of the Rocky Mountains and the Pacific Coast is to be settled, of course, by practical experiment. Meanwhile; as I have had occasion to point out, the proximate analyses of these coals throws little light upon it, and is, indeed, likely to mislead the metallurgist, if he compares it with the results of similar analyses upon bituminous and semi-bituminous coals. With the view of showing how large a proportion of the material usually classed as." volatile matters " consists of combined water, or oxygen and hydrogen presumably in chemical combination, I have collected a number of ultimate analyses from various sources, in the following tables. The numbered analyses in the first table are as follows

Jan 1, 1874

NEW MEMBERS The following list comprises the names of those persons who became members during the period of Mar. 10, 1917, to Apr. 10, 1917. ADKINS, HARVEY S Adkins & Denham, Engineers, Box 291,. Hazard, Ky. ANDERSON, ARTHUR P .... Leaser, Gibson Copper Co., Box 1978, Miami, Ariz. ARNOLD, EDWARD C... Min. Engr., Chief Engr., Federal Lead Co., Flat River, Mo. ASKIN, THOMAS B. H., Ball Mill Expert, Inspiration Cons. Copper Co., Miami, Ariz. BAIN, C. KREMER Butte & Superior Mining Co., Butte, Mont. BAKER, WILLIAM A.,.JR., Vice Pres. & Sales Mgr., The Georges Creek-Parker Coal Co., 306 North Gay St., Baltimore, Md. BOOTH, GEORGE H Mech. Engr., Inspiration Cons. Copper Co., Miami, Ariz. BRIDGMAN, G. TEMPLE, Asst. Consulting Mining Engr., Guggenheim Bros., 120 Broadway, New York, N. Y. BROOKS, CHARLES A Mine Surveyor, Homestake Min. Co., Lead, So. Dak. BUTCHER, FREDERIC E., Secretary, Missouri Metals Corpn., 1945 Railway Exchange Bldg., St. Louis, Mo.

Jan 5, 1917

By T. R. Scott

The acid pressure leaching of zinc-lead flotation concentrates from the McArthur River deposit, Northern Territory, Australia, has been studied in a three-stage, continuous, co-current system, using titanium reactors of 6 gal capacity. The starting pulp contained 2.7 lb solids per gal of synthetic spent electrolyte and the final liquors contained 120-125 gpl Zn. Parameters investigated included temperature (95-120°C), oxygen pressure (30-100 psi), acid addition (80-130% of theoretical), and leaching time (35-65 min per stage). Technical factors studied included mixing and pumping of feed, agitation, settling and washing and control mechanisms. The chemistry of liquor impurities, of scale formation in autoclaves and of lead jarosites in residues was studied in some detail. Results indicated that 90-93% zinc recovery could be obtained with a "low- acid" process, using 113°C and 70 psig with oxygen as the favored operating conditions. Residues contained 16-18% elemental sulphur and 15% lead, together with unreacted pyrite and gangue minerals. Pelletizing of residues was impracticable, and alternative suggestions for the recovery of lead, sulphur and silver are discussed. Preliminary estimates for plant and operating costs are given and enable some comparison to be made with conventional procedures.

Jan 1, 1973

By W. R. Hibbard

The increased strength of a polycrystal-line metallic aggregate compared with that of its individual crystals generally has been associated with complex stress distributions at the grain boundaries resulting from atomic irregularity between grains. This disregistry, together with the necessity for adjacent crystals to deform compatibly regardless of the single crystal crystallo-graphic strain mechanism, complicates this mechanism so as to increase the metal's resistance to deformation. Although Taylor1 has shown from purely mechanical considerations the requirement for at least five active slip systems to absorb the complexities during the homogeneous deformation of polycrystalline face-centered cubic metals, experimental studies by Barrett and Levenson2 indicate that this is feasible only in a qualitative sense because of deviations from homogeneous deformation. Seitz and Read in their review3 state: " Unfortunately . . . present knowledge of the grain boundary influence is not sufficient to complement the work in single crystals and provide us with a good foundation for treating polycrystals." The purpose of this investigation was to attempt to clarify the gap between single crystals and crystalline aggregates by an analysis of the effects of dcformational stresses. Some of the results were described by C. H. Mathewson in his 1943 Campbell Memorial Lecture.zl Previous Investigations Since the performance of single crystals deformed under pure stresses has been relatively thoroughly investigated, the most significant researches are concerned primarily with deviations from single crystal behavior of large grained specimens. Qualitative grain boundary effects involving the observed amount of slip werc reported by Carpenter and Elam5 in 1921. Individual crystals in a two or three grained aluminum specimen deformed by tension acted in the normal manner described by Taylor and Elarn4 except for marked modifications at the grain boundaries. There the power to withstand deformation was considerably increased, leaving a ridge on the specimen where decreased slip occurred, often noticeable yi in. from the boundary. Adcock,6 Yamaguchi,' Seumel, Hirstg and others have also reported this phenomenon as a qualitative trend. Yet attempts by O'Neill'o and Ljunggrenll to measure a difference in hardness at grain boundaries in undeformed specimens were unsuccessful. Miller12 measured quantitatively the reduction in slip near the boundary between the single crystal and polycrystalline areas of zinc specimens. These effects consisted of two parts: I. Next to the polycrystalline interface thc distribution of stresses was so altered

Jan 1, 1949

By Elbert Rowland

THE widespread interest in the alloys of beryllium with copper is due principally to the fact that certain compositions show very favorable precipitation-hardening characteristics and are, in fact, the strongest nonferrous alloys known at the present time. Investigations have been conducted by Masing and Dahl and others on the physical characteristics of ternary beryllium alloys, in an attempt to produce precipitation-hardening effects with a smaller amount of beryllium than that required in the binary copper-beryllium alloys (2.0 to 2.5 per cent Be). The results of these investigations show that ternary alloys of beryllium with Cu-Sn, Cu-Al and Cu-Zn, among others, exhibit promising improvements in physical properties after precipitation-hardening treatment and, while the increases in properties obtained are not as high as those realized from the binary copper-beryllium alloys, excellent properties are obtained with beryllium contents averaging about one-half the amount required in the binary alloys. This paper presents the results of an investigation of the equilibrium relations of certain alloys containing copper, tin and beryllium. The alpha-phase boundary of the ternary system is given for alloys containing from 0 to 1 per cent beryllium. The equilibrium conditions beyond the alpha-phase boundary are presented for alloys containing up to 32 per cent tin and 1 per cent beryllium. The data were collected by means of

Jan 1, 1935

By William H. Morris

At the Glen Summit meeting, the question of controlling the silicon in pig-iron WAS raised; and as this has been deemed by most furnace-men for years past a matter of special difficulty, an account of our experience in the matter may be of interest. When running on mill-iron, some years ago, we aimed to keep

Jan 1, 1893

By Prakash C. Kapur

Many balling and gradation system6 generate self- similar size distributions of the agglomerates. Inspection of the experimental data shows that this is also true of the steady state distributions resulting from the granulation of coarse, partially wet powders, for example, the fertilizer feeds. This result is exploited in the derivations of a number of simple and useful relationships that are pertinent to the analysis of these agglomeration systems. The bonding liquid demand of the granulating charge is a third order polynomial function of the dimensionless ratio of feed particle size to median granule diameter in the weight-fraction distribution. The median size, in turn, is the scale factor or characteristic size parameter in the similarity distribution. The granule size distribution, therefore, is completely specified by the liquid content and the similarity function, and so are the process efficiency and the ungranulated component In the product at steady state.

Jan 1, 1977