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By C. R. St. John, R. W. Lindsay, Charles R. Austin

MANY of the factors influencing the creep behavior of ferrous alloys have been investigated and reported upon in the literature, including such variables as grain size, steelmaking practice, nature and stability of the microstructure, and the effect of alloying elements in steels. However, with respect to the latter, the microstructures involved are usually heterogeneous and as a result the effect of the addition is related to its effects on the various phases present in the microstructure. In the instances where this structure consists of ferrite and carbide, the behavior of the alloy addition will be related to its action in strengthening ferrite and in opposing temperature softening of ferrite as well as coalescence of carbide. The present paper is the third in a series comprising a comprehensive review of investigations on the properties of iron binary alloys. 1.2 Its purpose is to describe the results of isolating one microstructural phase, namely ferrite, and studying its creep characteristics in both the unalloyed and alloyed conditions. This should aid in establishing to a large degree the importance of ferrite in the creep behavior of steels consisting of the previously mentioned ferrite-carbide aggregate. REVIEW OF PREVIOUS WORK In view of the fact that the present investigation deals only with the effects of silicon, manganese, chromium, molybdenum, nickel, and cobalt, and to a certain extent with the effects of carbon, the review of previous literature will be confined to these elements. Practically no references were encountered dealing with the influence of these elements on the creep characteristics of the isolated phase. However, various contributions have dealt with the creep behavior of low-carbon steels alloyed with the elements under consideration. A particularly concise review in this respect is given by Bullens (Battelle)3 and much of this material has been drawn upon. The definite improvement in creep resistance and high-temperature strength conferred by molybdenum is well known. Published suggestions by the A.S.M.E.4 permit of an increase of some 2000 to 5000 lb. per sq. in. in permissible design loads over a temperature range from 650° to 1000°F. as a consequence of additions of 0.40 to o.60 per cent of this element in carbon steels of the order of o.25 to o.35 per cent carbon content. Babcock and Wilcox Tube Co.5 has published data showing the pronounced increase in stress necessary to cause one per cent creep per 10,000 hr. when additions of 0.5 or 1 per cent molybdenum are made to a plain carbon steel. These data apply to temperatures over a range from 800° to 1000°F.

Jan 1, 1945

By A. A. Venghiattis

This paper is discussed not because of its intrinsic value but because it has been related by its authors to the oilwell gun perforators. It is well known that conditions almost ever present in oilwell perforations are the overburden and the presence of the casing. Because of the lack of information in the paper on the dimensions or confinement of the target rocks, one is led to guess that they were not confined at all and, particularly, that no steel front plates were used on the impact face of the rocks to materialize the presence of the cemented casing. This situation, plus the fact that small steel balls have been used as projectiles instead of actual bullets, makes the whole thing unapplicable to oilwell perforation. When shooting is performed against target rocks confined (as shown on Fig. 1) in such a way as to give a fair image of the overburden applied to the formation to be perforated, as well as of the cemented casing, the following are found. 1. There is no cratering worthy of mention, even with bullets having 10 times higher impact energy per unit projected area than the steel balls mentioned in the article. This has been confirmed with sandstone as well as with other rocks (granite, limestone and chalk). See Figs. 2 and 3. 2. Penetrations vary closely as the logarithm of the impact velocity. On this matter I have established the relation

By E. J. Roberts, E. B. Fitch

THE mechanism of classification by settling pools is most simply shown in the case of batch sedimentation such as was analyzed by Oden.1 The batch model will be considered, therefore, and it will be shown that the same mechanism applies to continuous operation. Classification in Batch Settling Pools: Consider a beaker or tank of slurry containing particles so dispersed that they can settle independently of one another under the influence of gravity. Originally all particle sizes are uniformly distributed throughout the suspension. All particles start immediately to settle towards the bottom at rates determined by their size, shape, and density—among other factors. Particles reaching the bottom settle out of suspension. After some given time the slurry above the deposited solids is siphoned off or otherwise removed, leaving the deposited solids behind. The deposited solids, together with entrained and any unremoved supernatant slurry, represent the underflow of a classifier. The slurry removed represents the overflow. There is a certain separation, size of particle which during the sedimentation has just time to settle from the top surface of the slurry to the level at which underflow and overflow are parted. All particles with a faster settling rate will have dropped to below this level, no matter where in the beaker they started from originally, and therefore will be absent from the overflow. Particles with a slower settling rate will not reach this level if they started from the top of the slurry, but a portion of them,

Jan 1, 1957

As already announced, the Arizona Meeting of the Institute is to be held from the 18th to the 25th of September. There will be a special train from New York City to Arizona and return, to take members and guests of the Institute to the meeting. The Committee in charge consists of Walter Douglas, Chairman, Cleveland E. Dodge, John C. Greenway, Arthur S. Dwight and Julius Kruttschnitt, Jr., and while the plans of this Committee are not complete, it may be announced that the train will be run with the requisite number of Pullman, dining and baggage cars to accommodate those who desire to go, which will accompany the party during the entire week of the Arizona Meeting as per the following program, including, of course, the visit to the Grand Canyon. As soon as details have been worked out, a circular will be issued giv¬ing full information concerning the trip.

Jan 7, 1916

By Harold F. Yde

Hydraulic tailing fill in the Butte deep-level mines resulted from studies made in 1958 by The Anaconda Co. Mining Research Department. At the time of the study, dry mine tailing was hauled via rail cars from the Anaconda tailing ponds, 25 miles distant, to the tailing fill plants of the underground mines at the Leonard, Anselmo and Mt. Con mines. Presently, tailing from the Weed concentrator in Butte is delivered to the Kelley shaft via pipeline and stope filling has become automated. Tailing at 30% solids is pumped 8000 ft horizontally and upward from the concentrator to the Kelley fill plant, where it is dewatered and deslimed by three Krebs cyclones. These discharge the material into the cased and grouted mine delivery boreholes at desired densities of up to 70% solids. The vertical boreholes and 4-in. rubber-lined Victaulic pipe carry the material downward to horizontal distribution lines, which in turn tap into the 3-in. stope-filling, unlined Victaulic pipelines.

Jan 1, 1970

The members of the Institute living in the lower Mississippi Valley, I extend a hearty and cordial invitation to their fellow-members to meet with them nest October, in St. Louis. They believe that it will be a meeting of singular interest, inasmuch as the district in question can show in active production almost all of the more useful metals and non-metals. Perhaps too few know that the Southeast Missouri District, about 80 miles south of St,. Louis, and to which a special trip is planned, is the largest lead district in the world. It was that before-the European war, and, now that the production of lead has greatly increased abroad, and has correspondingly increased in the United States, this is one of the most interesting of all lend districts. In 1913, the production of the world was 1,270,000 tons, the last world figures obtainable. In that same year the production of the United States

Jan 5, 1917

By B. E. Hoffacker, R. E. Lund, J. Ferrighetto, G. E. Welch

Since October 1965 the Josephtown Smelter of St. Joseph Lead Co. has commercially applied the Heavy Media Separation process to reclaim zinc and reject gangue from electrothermic zinc furnace residues. In addition, heavy medium is produced from the ferrosilicon which is present in the furnace residues. By way of background, the Josephtown Smelter produces zinc metal and zinc oxide by the electro- thermic process. The principal feed to the vertical shaft electric furnaces is sized sinter and coke. Temperature of the charge in the furnaces varies from roughly 900°C near the wall to 1300-1400°C in the central regions. Zinc smelting is rapid and nearly complete in the main body of the charge, but little zinc is smelted near the wall. In addition to fusing high gangue content particles, the high temperatures promote side reactions, the most important of which is reduction of iron oxide and silica to form a low grade ferrosilicon containing about 82 % Fe and 13% Si.

Jan 12, 1968

By Ali M. Heidarieh Zadeh, Raghu N. Singh

The paper presents a stability investigation of shaft intersections and pit bottom roadways in the vicinity of upcast and downcast shafts at a colliery in the U.K. Aschemeof instrumentation was aimed at monitoring the strata displacement surrounding the pit bottom roadways and shaft intersections with a view to ascertaining the origin of the strata movement and effectiveness of the control measures. The bore- hole instrumentation results together with a theoretical analysis suggested that the cause of instability could be attributed to the drivage of a roadway within the shaft pillar. A semi-empirical technique was used to calculate the amount of support resistance required to reinforce the pillar to take additional abutment load. A rock bolting system was designed to provide a required increase in thrust capacity of the roadway support. The results indicated that roadway closure was effectively controlled after installation of bolts indicating efficacy of the control measures adopted.

Jan 1, 1982

By J. H. Canterford

The adsorption of uranium onto Wyoming bentonite was measured in carbonate media over the pH range 8 to 11. Uranium was removed from solution onto the solids by a rapid reaction, proposed to be adsorption of the anionic uranyl tricarbonato complex onto edges of the clay platelets, and a slow reaction that may be precipitation of a hydroxide. The changes in uranium content of the aqueous and solid phases of a uranium ore carbonate leach slurry were also measured as the slurry was progressively diluted. There was an increase in the uranium content of the solids as the pH of the suspension was lowered, as observed with the Wyoming bentonite. Results indicate the conditions that should be met with respect to pH control to prevent the problem of excessive uranium adsorption in the counter-current decantation washing circuit of a conventional leaching process, as well as in the leaching and restoration phases of carbonate solution mining.

Jan 1, 1985

By C. Edward Capes

Fine particles in liquid suspension can be agglomerated by a number of mechanisms. Well-known methods include the addition of electrolyte to reduce the zeta potential and allow mutual adhesion arid the use of polymeric flocculants to bridge between the particles. A more recent technique, "spherical Agglomeration", is the subject of this paper. The process involves the addition of a second liquid which is immiscible with the suspending liquid and preferentially wets the particles to cause particle adhesion by capillary liquid bridges. Progress in the application of spherical agglomeration to a number of distinct technological fields is reviewed in this paper. The areas of interest include the formation of dense, highly spherical agglomerates, the separation of solids from suspension and the fractionation of complex, multi-component solids mixtures, such as ores. Some of the more interesting recent applications in the energy and environmental fields, such as the beneficiation of' coal and tar sands, are highlighted.

Jan 1, 1977

By G. R. Wilms

In a recent investigation1 on the properties of chromium, and of Cr-10 wt pct W and Cr-5 wt pct Mo alloys at elevated temperatures, it was found that intercrystalline cavities developed in all of these materials during tensile creep at 950°C, and that the cavities led to intercrystalline fracture. There were some interesting differences, however, between the cavities produced in the pure metal and those in the alloys; these differences, moreover, were associated with a difference in ductility. The relevant conditions of creep testing are specified in the captions to Figs. 1 and 3. Chromium showed the presence of quite large intercrystalline cavities, Fig. 1, and these were more or less randomly distributed around the boundaries. The chromium alloys, on the other hand, showed the presence of both small cavities and cracks at the grain boundaries, Fig. 3; it is apparent that the cracks are formed by the linking together of the small cavities. Moreover, the cavities and

Jan 1, 1960

By William C. Alden

A great landslide occurred on June 23, 1925, in the valley of Gros Ventre River, about 35 miles south of Yellowstone National Park (Fig. 1). The relations of the north-easterly dipping rock formations of the slide scarp and of the dam formed by the slide are shown in the diagrammatic cross-section of the valley (Fig. 2). This generalized section is based on unpublished maps and notes by Eliot Rlackwelder, in the files of the IT. S. Geological Survey. Heavy rains and melting snow in the Gros Ventre Mountains had saturated clay layers in the Carboniferous strata, which dip toward the valley at angles of 18" to 21°, consequently an enormous mass of rock at the end of the north spur of Sheep Mountain became loosened and, on the afternoon of June 23, slid suddenly down into the valley. Within a few minutes this mass of debris—estimated as 50,000,000 cu. yd.—carrying

Jan 1, 1928

By C. C. Furnas

IT is well known that particles of different sizes are not distributed evenly throughout the average charge in an iron blast furnace. Just how great the disparity in particle size in different parts of a single plane in a furnace may be is indicated by the results of some recent investigations1 conducted by the Bureau of Mines on a furnace operating on Lake ores. The wide variations found in gas velocity, gas composition, and temperature from the periphery to the center of the upper charge column were caused by the great variation in particle size of the raw materials used and were also greatly influenced by the methods of charging. This paper summarizes the results of an investigation of the influence of different methods of charging and of the treatment of raw materials upon the size distribution of the solid particles in the blast furnace. A more complete report will appear later as a Bureau of Mines technical paper.

Jan 1, 1929

By A. J. Brown

I HEREWITH send to the Institute a sample of Pancake coal. It is rather early yet to make any estimate of the future value of the discovery; but it is certainly the most promising vein of coal yet discovered in the State of Nevada, and, I believe, the first true coal found west of the Rocky Mountains, or perhaps west of the Missouri River, unless some of the Utah coals belong to the coal measures of the Carboniferous age. The Pancake vein certainly belongs

Jan 1, 1875

By Charles A. Kliche

INTRODUCTION The Northern Great Plains Coal Province which occupies approximately 36.6 ha contains about one-half of the nation's total coal resources. About one million ha are underlain by coal that is considered to be mineable from the surface. The topography of the province is predominately plains, rolling hills, and some badland areas characterized by breaks or sharply eroded hills. Elevations range from about 1500 m above sea level on the west to about 600 m above sea level on the eastern boundary. The average slope of the ground is approximately 2 m per km. Streams in the province drain generally easterly and southeasterly (1). In the United States, the Northern Great Plains Province lies within the states of North Dakota, South Dakota, Montana, Wyoming, Nebraska, and Colorado. The coal within the province is located almost entirely in the states of North Dakota, Montana, and Wyoming. Although it is relatively low rank, the coal within the province encompasses a large portion of the total remaining U. S. reserves. The U. S. Geological Survey estimates the total remaining coal resources of the United States to be 2.6 trillion mt within 1000 m of the surface, and 2.9 trillion tons within 1830 m of the surface. Of this total, only about 177 billion mt are classified as reserves meaning that they are (1) known in location, quantity and quality from geologic evidence supported by engineering measurements, and (2) economically recoverable based on currently available technologies and current market value (2).

Jan 1, 1983

By A. R. Denison

This field in 1933 continued as in 1932, although to a much less extent, to dominate the drilling and production situation throughout the oil business. The 2466 producers completed in this field during the year are 28 per cent of such wells completed in the United States. The 2556 completions reported in the five counties within which the East Texas field lies are 21 per cent of all such wells reported in the United States. It follows that with such a command of the development situation, every other factor with regard to this field has an important bearing on the entire oil business. As a consequence, the important developments in the East Texas field are the important developments of the year. Very little new productive territory was added to the already known limits of this enormous field. On the other hand, drilling has shown that with a few very minor exceptions this field is a continuous productive area, with a regular outline and no "dry spots" other than that of a single well surrounded by producing wells. Drilling was confined to the already proven limits of the field. This consisted essentially of more adequate coverage of leases by wells, the meeting of required offsets and the drilling of a large number of small tracts which developed from subdivision of larger leases due to court action and other causes. The allowable throughout the year was, with minor variable factors, on a per-well basis. With the steady decline in per-well allowable after May, every operator was faced with declining

Jan 1, 1934

By W. J. Reagan

A survey of the literature on bottom-cast practice gives but Scant information as to some of the real facts concerning this most int'eresting method of steel manufacture, and some of the information available is very misleading. An exceptionally good description of this met,hod of pouring or teeming is to be found in an English publication2 on the heterogeneity of steel ingots. Quoting from this paper: (a) With bottom teeming, the metal rises steadily and progressively in the mold with the minimum possible agitation, the main force of the stream coming from the ladle being broken down or retarded by the down gate or runner. Further, the stream of metal from the ladle, under these conditions of casting, is invariably maintained at a much more continuous rate and is steadier than with top teeming. (b) In view of the facts referred to in (a) it follows that with bottom teeming the metal is not exposed to atmospheric oxidation to anything like the same degree as with top teeming. In this paper it is intended to detail briefly some of the advantages of bottom-cast practice and to discuss the possibilities of iron-oxide control in the basic open-hearth furnace. A description of the type of charge, ingot rnold set-up, etc., is found in detail in an earlier paper.3 Design of Ingot Molds In any kind of steel manufacture, ingot-mold design is important. L. H. Nelson4 lists in the order of their probable importance the following factors as influencing most the solidification of the ingot:

Jan 1, 1934

By Carl Floe

THE possibility of separating the various constituents of mixed ores or metalliferous products by differentially producing their soluble sulfates has not received the consideration that it deserves. The production of the soluble sulfate may be accomplished by baking the ore with sulfuric acid or by treating it with gases containing oxides of sulfur. This paper is primarily concerned with the first method. The procedure used was to mix the material with a solution containing a definite weight of sulfuric acid, baking the mixture at various tempera-tures and then leaching out the soluble sulfate with water. The amount of acid used was calculated to produce certain desired soluble sulfates. The temperature of baking depended on the decomposition points of the sulfates involved. The object was to prevent the formation of or to decompose certain sulfates while leaving a maximum quantity of another sulfate in a water-soluble form. This procedure has two possible advantages over the ordinary method of leaching with an aqueous solution of sulfuric acid. First, a more selective leach may be obtained, and second, the higher temperatures and stronger acid concentrations involved will permit a better recovery of materials that are difficultly soluble in relatively dilute aqueous sulfuric acid solutions. The method of sulfuric acid baking followed by water leaching is not new, as it has been applied in the treatment of various metalliferous materials such as the recovery of cadmium from flue dust1, the re-treat-ment of zinc leach residues2 and the working up of electrolytic slimes3.

Jan 1, 1936

By W. H. Emmons

MANY mineral veins occupy faults, and movements on certain warped fault planes have resulted in openings. On normal faults the [ ] steeper parts have the widest openings, and on reverse faults the flatter parts have the widest openings. Theoretically the width of the opening is the sine of the angle of deflection times the amount of movement on the fault plane, but actually the widths of some of the openings are probably less because of readjustments of walls along joints or of other readjustments. The first treatment of the subject seems to have been in a book on mineral veins by John Leithart, published in Newcastle, England, in 1838. Later the subject was treated in various texts published in Germany, in England, and elsewhere. The subject was not given much prominence in the earlier American literature on economic geology, but has interested several workers in that field in the past decade. In this paper examples of districts showing ore shoots on warped faults, with relations noted, are described. Fault veins of the three depth classes of veins are noted. Many epithermal veins are in normal faults, and commonly the larger ore shoots are in their steeper portions. Many mesothermal veins are in reverse faults and many others are in normal faults. The flatter parts of veins in reverse faults are commonly wider than the steeper parts, although they are not always as rich as the steeper segments of the veins. There are not many hypothermal veins in faults of measured displacement.

Jan 1, 1943

C. W. GOODALE, * Butte, Mont.-In regard to the employment manager, the North Butte Mining Co. has undertaken that line of work and the rest of the companies are watching the experiment. If it is proved to be the proper thing, the system will be introduced into other mines. We have to combat the opposition to the use of the "rustling card. It is nothing more nor less than asking the nationality, where the plan formerly worked, and whether he is married or single. ROBERT RHEA GOODRICH, Anaconda, Mont. (written discussion?).¬Since the efficiency of the different phases of personnel work employed by industrial concerns, which are bringing about greater efficiency and lessening the labor turnover, the latter being intimately connected with "contentment of mind," depends on the individual workman, it is highly desirable, as far as industry is concerned, to keep the workman's mind and body in trim in order to lessen accidents and produce a higher grade of work. Prevention being better than cure, health supervision of the workmen during employment should be maintained by the employers in order that mental alertness and physical well-being may be obtained. I have long believed, from observation in many plants, that when any problem is dependent on the individual workman, what he believes and what he does is vitally dependent on his health. I will follow with much interest what is to be clone in the future in relation to the subject of health supervision during employment (as well as medical examinations at the time of employment), and I hope this idea will be generally instituted in personnel work. A workman with good health and a contented mind should be an ideal component of a progressive industrial concern. The contentment of the workman is fostered by a number of admirable phases of welfare work which are being still further developed. The mental and physical well-being of labor should be the issue in Labor vs. Capital in the new period of the industrial promotion of the United States into which we are now entering.

Jan 4, 1919