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By Harry M. Mikami

Refractories are heat-resistant, generally nonmetallic materials used as the linings of furnaces or high temperature vessels in the steel, iron, nonferrous metals, glass, cement, lime, ceramic, chemical, petroleum, paper, and power and heat generation industries. Refractories must have structural strength at high temperatures but also, in many applications, must simultaneously resist chemical-physical corrosion-erosion from stags, metals, granular solids, or gases. Among the major uses are the pyrometallurgical processes for producing iron, steel, copper, aluminum, nickel, lead, zinc, etc. Rotary cement kilns, glass tanks, refineries, utility boilers, chemical and ceramic (including refractories) plants, and a myriad of other smaller scale users employ refractories in the high temperature parts of their operations. Thermal, chemical, and structural conditions under which refractories are used differ widely so there is a great variety of refractories to fill the various needs. Two major classifications are the "basic" and "acid" types. Basic refractories include magnesia and chromite, singly and in combinations, dolomite, and forsterite (olivine). The acid category includes aluminosilicates, alumina, and silica. There are a number of other specialized types such as carbon, graphite, silicon carbide, zircon, and zirconia that have important applications but are used in much smaller amounts than the major categories. Physically, refractories can be divided into bricks and shaped products on the one hand and unshaped or monolithic products (also termed specialties) on the other. There are many further subclassifications and divisions, a discussion of which is beyond the scope of this chapter; see Refs. 2 and 9. Raw materials for the principal basic refractories are magnesia and chrome ore. Magnesia, generally termed magnesite or periclase, is obtained mainly from seawater or saline brines extraction, but substantial amounts are produced from mined magnesite (MgCO3). Dolomite (CaCO3•MgCO3), another important basic refractory, is obtained entirely from mined sources. Acid refractory raw materials are: fire clays, flint clays, kaolin, and other natural clay minerals; aluminosilicate minerals such as kyanite, andalusite, sillimanite, pyrophyllite, bauxitic clays; calcined refractory grade bauxite, alumina from the Bayer process for the alumina group; and quartzitic rocks for silica refractories. The total value of all refractories shipped in the United States in 1974 was $989 million, a record to that date. Of this amount, about 73% represents bricks and shaped products and 27% is in nonshaped or monolithic products which comprise mortars, cements, castables, plastics, and ramming and gunning mixes. Fig. 15.4E.1 shows the rising value of all U.S. refractory shipments in the period 1948-1974. Values of brick and shapes paralleled

Jan 1, 1976

By Harrison Everett Ashley

Slimes are usually defined as all material passing a certain sized sieve, which is invariably the finest sieve employed by each metallurgist in his tests; 100-mesh and 200-mesh have been taken as the limits by different writers in recent volumes of the Transactions; 150-mesh is common practice. The reader of the first two volumes of Richards' is impressed by the inflexibility with which all grinding-arrangements are praised or condemned according as they make little or much slime. Until recently, one of the principal aims of the mill-man was to keep down the slimes. He was obliged to have separate apparatus for sand- and slime-treatment. The latter was sometimes puzzling and erratic. Often it was found most economical to omit treatment of the slimes entirely, or to store them in immense basins or heaps, waiting for possible future improvements in methods of treatment. Recently, improved processes of agitation and filtration have made possible the successful extraction of values from many slimes. The tendency, when the metal is exceedingly finely disseminated, is to cut out all sand-treatment and to slime everything. These processes have been almost entirely mechanical in their conception, and it is the object of the present paper to show that certain chemical considerations may greatly hinder or assist their successful operation. It has long been a source of dissatisfaction to chemists that their analyses fail to be of much help to the clay-worker; that it is a matter of common occurrence for clays of closely identical ultimate chemjcal constitution to show the widest possible divergence in physical properties.

Jan 1, 1911

By Robert Uhley, Tsvi Meidav, L. Scharon

Before National Lead built an industrial plant on its Fredricktown property, some 100 miles south of St. Louis, a 750x500-ft area on the proposed site was investigated by electrical resistivity, seismic refraction, and churn drilling. Data were accumulated to prepare an isopach map of the overburden and to determine soundness of the dolomite bedrock and the depth to bedrock at fixed points. The site was on a gently sloping hillside. Elevations above sea level ranged from 760 ft in the northwest corner to 820 ft along the eastern edge, giving a total relief of 60 ft. There were no major drainage features, but in the northern part of the plant site there was an indicated depression area which later was interpreted as reflecting subsurface conditions in the bedrock. No rock was exposed in the entire plant site area; the surface was characterized by soil and overburden. GEOLOGY Prevailing geology in the area of investigation was relatively simple—Bonneterre dolomite overlain by residuum. The red overburden was that derived from the weathered Bonneterre. Some chert was present, interpreted in the general area as a weathering of both the Bonneterre dolomite and younger sedimentary rocks such as the Potosi dolomite. During the period of actual measurements the residuum varied from moist near surface on the western edge of the proposed site to dry near surface on the eastern edge, and for this reason overburden resistivities ranged from low on the west to high on the east. Seismic velocities were low, since the material was not well packed. The bedrock encountered was dolomite, specifically the Bonneterre of Upper Cambrian age which, according to McQueen,' consists of an upper dark gray member and a lower light gray member. These have been further divided into four zones, in ascending sequence a dark gray, sandy argillaceous dolomite; a dark brown or black, fine-grained dolomite: a light gray, finely crystalline, compact dolomite; and, at the top, a dark brown, finely crystalline, compact dolomite. In the area of investigation the upper two zones were encountered in the drilling tests as constituting the bedrock. The dolomite varies widely in porosity, which is low in the dense, fine-grained layers. In this area, therefore, both electrical resistivities and seismic velocities were high. Fracture zones in the Bonneterre are nearly Geology, and may extend to some depth, causing considerable deep weathering. It was realized that over deep fracturing the apparent resistivities

Jan 1, 1960

By Eugene Coste

ALTHOUGH some of the observers who first paid especial attention to the occurrences of oil and gas in the strata (such as Hunt in 1859, Andrews in 1861, Winchell in 1865, Mendelejeff in 1876, Höfer in 1876, Minshall in 1881, and I. C. White in 1883) seem to have been impressed with the fact that oil and gas deposits were connected with the disturbances in the rocks caused by their upheaval,1 yet, with the exception of Mendelejeff, and possibly Andrews, these observers do not appear to have understood what is really the one essential factor in the occurrence of oil and gas in the strata: viz., the faulting, uplifting, fracturing, fissuring, and jointing always accompanying even slight rock disturbances, and in certain districts (petroliferous provinces)2 allowing solfataric hydrocarbon emanations to force their way up from the interior and to reach and impregnate the porous portions of sediments subjected to the disturbances. Instead of this simple explanation to account for the observed connection between petroleum deposits and rock disturbances, most of the observers mentioned above, and many others who have followed them on the name lines since, have entirely reversed the problem. To them, instead of the dissemination of gases from fissures into the sediments, it presented the accumulation and concentration, according to anticlinal or other geologic structures, of oil and gas originally present throughout the whole mass of the strata where they were produced by the decomposition or distillation of organic remains. Whether this important problem involves accumulation from sources within the oil-bearing strata themselves, or infiltration and dissemination from outside sources, may be easily determined if all preconceived ideas are put aside and the established facts only are considered.

Jan 9, 1914

By C. D. Ramsden

DURING the war years of 1941 to 1945, maintenance of mine locomotives and other mine equipment took the form of rebuilding rather than of renewing. Pur¬chase of new parts became increasingly difficult and mine operators found it necessary to maintain equipment by sal¬vaging old parts. Mine-locomotive wheels, although not representing a high cost per pound of material, contain a con¬siderable amount of steel and without rebuilding would have to be scrapped long before even a moderate percentage of the steel in the wheel is actually consumed. Many mine operators have been re¬building locomotive wheels for several years with automatic open arc-welding equipment. In 1927, the Pittsburgh Coal Co. started such a program, using a single Westinghouse automatic welding head. Since that time, many refinements have been added, until in 1944 the setup was operating very efficiently. A desire to increase wheel life and to hold down rising costs led the company in 1944 to investigate the possibilities of the under¬flux arc-welding process for wheel rebuild¬ing, although at that time, little or no work had been done on multiple pass or "build-up" welding with the underflux arc. Work with this process had been confined largely to welding together flat plates in a "down hand" position. Possibilities for savings were intensified by the fact that the company has 300 locomotives in operation, using actively or as spares 1200 sets of wheels. During 1942 and 1943, about 500 sets of wheels were sent each year to the company's maintenance shop at Library, Pa., for rebuilding. Based on having 800 sets in service (many of the company's heavy locomotives have three- sets of trucks), the average life of a set of wheels was approximately 19 months. Anything that could be done to increase wheel life promised sizable annual savings. OPEN ARC WELDING With the open arc process, a set of wheels could be rebuilt for about 40 pct of the cost of new wheels. Underflux arc welding gave promise of greatly increased welding speeds, more homogeneous, dense deposits and the chance for use of a wider range in welding-wire compositions. Against this was ranged the higher cost of materials and the cost of developing the process from the theory to a practical reality. Since 1927, when a single open arc head was placed in operation, fixed welding procedures had been gradually developed, a positioner for handling a set of wheels was built, and a second head was placed in operation in order to weld two wheels simultaneously. The fixture, or posi¬tioner, which was built to position and turn the wheels under the two welding heads, included a motor drive, controlled by a rheostat, which rotated the wheels through a double set of speed reducers and a removable jaw coupling attached to one end of the axle of the wheel truck.

Jan 1, 1946

By Clemens Jones

The peculiar property of the lode-stone has been known for many centuries. It was very early observed that, by contact with it, iron is magnetized; and it is needless to dwell here upon the history allied to this discovery, now constituting the wonderful science of magnetism. Deposits of magnetic ore are distributed all over the world. The ore is sometimes very rich and comparatively free from gangue, sometimes sparsely disseminated in the native rock. These bodies of lean ore often cover large areas. Modern ingenuity has utilized the principle of the magrtet, originally derived from the ore itself, and really belonging to the time of Plato and Theophrastus, to separate the magnetic ore-particles from the rock which has previously been crushed. This process recovers the ore in the state of a concentrate very rich in iron and, in some cases, desirable for Bessemer purposes. The magnetic separator is no longer a novelty. It was only at the last meeting of the Institute in New York, that Messrs. Birkinbine and Edison (Trans., xvii., 728) and Mr. Robert Cook (Ib., 599) described some of' the principal designs of apparatus in use. E. S. Dana classifies the natural magnetic minerals in the following order: magnetite, pyrrhotite, franklinite, almandite and minerals " containing considerable FeO." Of these, ferroso-ferric oxide, or magnetite, is the type. The proportionate amount of ferrous oxide essential to magnetize the compound, is not established. Ferrous oxide appears to be the only magnetic oxide of iron. Tissandier (Compt. Rend., lxxiv., 531) produced ferrous oxide in the anhydrous state, by the action of carbon dioxide on pure iron at a red heat, according to the equation : Fe + CO2 = FeO + CO. This is black, crystalline and magnetic. Heated to redness in the air, it is converted into Fe3O4. Sidot (Compt. Rend., lxvii., 175) has also produced an oxide exhibiting magnetic polarity, by heating ferric oxide to a temperature

Jan 1, 1891

By J. P. Kerr, W. H. Cordell

Conditions in the oil and gas industry in Indiana were about the same in 1935 as in 1934. This is especially true of the old Trenton area and the Harrison County area where production was steady and almost no exploration and development took place. The past year has seen an increase in drilling activity and a decrease in oil and gas output in southwestern Indiana. In the state, 224 wells were completed in 1935, of which 48 were oil wells, 61 gas wells, and 115 dry holes. A few of these were old gas wells deepened to oil horizons. Twenty-six wells started during 1935 were not completed by Dec. 31. Approximately one-half the wells drilled were within proven areas. A relatively large number of wildcats, especially in Daviess, Pike and Gibson Counties, were in search of new gas supplies to supplant the diminishing resources in those counties. The decreased production of gas was due largely to the fact that existing supplies declined more rapidly than new fields could be brought on. The Alford field, in Pike County, which produced the bulk of the supply in 1934, was called on to do likewise in 1935, but was unable to respond sufficiently to keep up the yearly production for southwestern Indiana. During the last half of the year, the Oaktown field, Knox County, was connected with one of the principal pipe lines of the state, which helped to keep gas production above an unusual low. The decline in oil production was due almost entirely to proration during the first eight months of the year. The proration affected Daviess, Pike, Gibson, Sullivan and Vigo counties, which produce about three-fourths of the total for the state. After proration was lifted, the wells never quite reached the conditions existing before proration. The average daily production per well in Indiana is less than two barrels. The outstanding development in Indiana in 1935 was the drilling in the Oaktown field immediately before and after the laying of the 6-in. pipe line to the field. Almost without exception the wells came in with an open flow of two to four million cubic feet. At the end of the year, 26 wells were connected to the pipe line. Development of this field will

Jan 1, 1936

By J. P. Kerr, W. H. Cordell

Conditions in the oil and gas industry in Indiana were about the same in 1935 as in 1934. This is especially true of the old Trenton area and the Harrison County area where production was steady and almost no exploration and development took place. The past year has seen an increase in drilling activity and a decrease in oil and gas output in southwestern Indiana. In the state, 224 wells were completed in 1935, of which 48 were oil wells, 61 gas wells, and 115 dry holes. A few of these were old gas wells deepened to oil horizons. Twenty-six wells started during 1935 were not completed by Dec. 31. Approximately one-half the wells drilled were within proven areas. A relatively large number of wildcats, especially in Daviess, Pike and Gibson Counties, were in search of new gas supplies to supplant the diminishing resources in those counties. The decreased production of gas was due largely to the fact that existing supplies declined more rapidly than new fields could be brought on. The Alford field, in Pike County, which produced the bulk of the supply in 1934, was called on to do likewise in 1935, but was unable to respond sufficiently to keep up the yearly production for southwestern Indiana. During the last half of the year, the Oaktown field, Knox County, was connected with one of the principal pipe lines of the state, which helped to keep gas production above an unusual low. The decline in oil production was due almost entirely to proration during the first eight months of the year. The proration affected Daviess, Pike, Gibson, Sullivan and Vigo counties, which produce about three-fourths of the total for the state. After proration was lifted, the wells never quite reached the conditions existing before proration. The average daily production per well in Indiana is less than two barrels. The outstanding development in Indiana in 1935 was the drilling in the Oaktown field immediately before and after the laying of the 6-in. pipe line to the field. Almost without exception the wells came in with an open flow of two to four million cubic feet. At the end of the year, 26 wells were connected to the pipe line. Development of this field will

Jan 1, 1936

By Leslie F. Tedsen, John E. Dorn, Alan E. Flanigan

It is necessary occasionally to use aluminum-alloy sheet where moderately elevated temperatures are encountered. Considerable attention has been directed toward determining the influence of "artificial aging" on the room-temperature properties of the precipitation-hardenable alloys, as testified by numerous company reports and by references I to 4. Investigations on the properties at elevated temperatures are few, however, and have not always covered the range of times and temperatures of greatest interest. The present investigation was instituted to overcome this deficiency. The work was done for the Office of Production Research and Development of the War Production Board, under the supervision of the War Metallurgy Committee, as a part of the "restricted" Project NRC-548. It has been released for publication by the Office of Production Research and Development. AS is well known, the high-strength aluminum alloys achieve their remarkable properties as a result of precipitation-hardening. In production they are subjected to a solution heat-treatment followed by quenching, to retain the supersaturated solid solution. The solution treatment is followed by "aging" (precipitation-hard- ening) either at room temperature or at a suitable elevated temperature. A considerable increase in tensile and compressive yield stresses results from precipitation at room temperature ("natural aging"). Through the elevated-temperature process ("artificial aging") it is possible to obtain values of yield stress considerably higher than those attainable by natural aging. The increase in yield stress is accompanied by a smaller gain in ultimate tensile stress and by a decrease in elongation. During the first stages of artificial aging the yield stress increases steadily until it reaches a maximum value. In this condition the material is said to be "fully aged." Further exposure results in "averaging," attended by a steady decrease in yield stress. In the production of the artificially aged materials, temperatures and times are selected to achieve full aging. The following important characteristics are associated with the process: 1. The higher the temperature, the more rapidly is the fully aged condition attained. :7

Jan 1, 1946

By Leslie F. Tedsen, Alan E. Flanigan, John E. Dorn

It is necessary occasionally to use aluminum-alloy sheet where moderately elevated temperatures are encountered. Considerable attention has been directed toward determining the influence of "artificial aging" on the room-temperature properties of the precipitation-hardenable alloys, as testified by numerous company reports and by references I to 4. Investigations on the properties at elevated temperatures are few, however, and have not always covered the range of times and temperatures of greatest interest. The present investigation was instituted to overcome this deficiency. The work was done for the Office of Production Research and Development of the War Production Board, under the supervision of the War Metallurgy Committee, as a part of the "restricted" Project NRC-548. It has been released for publication by the Office of Production Research and Development. AS is well known, the high-strength aluminum alloys achieve their remarkable properties as a result of precipitation-hardening. In production they are subjected to a solution heat-treatment followed by quenching, to retain the supersaturated solid solution. The solution treatment is followed by "aging" (precipitation-hard- ening) either at room temperature or at a suitable elevated temperature. A considerable increase in tensile and compressive yield stresses results from precipitation at room temperature ("natural aging"). Through the elevated-temperature process ("artificial aging") it is possible to obtain values of yield stress considerably higher than those attainable by natural aging. The increase in yield stress is accompanied by a smaller gain in ultimate tensile stress and by a decrease in elongation. During the first stages of artificial aging the yield stress increases steadily until it reaches a maximum value. In this condition the material is said to be "fully aged." Further exposure results in "averaging," attended by a steady decrease in yield stress. In the production of the artificially aged materials, temperatures and times are selected to achieve full aging. The following important characteristics are associated with the process: 1. The higher the temperature, the more rapidly is the fully aged condition attained. :7

Jan 1, 1946

By George F. Learning

TOTAL DIRECT IMPACT The uranium mining industry's principal economic impacts on the Texas economy are the result of three flows of money from the industry into the remainder of the state's economy. These three are: (1) money paid to individuals (personal income) ; (2) money paid to other businesses (business income); and (3) money paid to state and local governments (government revenues). As these direct payments from the uranium industry to various other sectors of the Texas economy subsequently circulate and recirculate within the state, the indirect effects of uranium mining's direct impacts multiply to reach amounts significantly higher than the direct income flows alone. Over the past decade, the uranium mining industry has substantially increased its role as a provider of jobs, personal income, business income, and government revenues in Texas. The growth has come almost exclusively in a largely rural, seven-county area that lies within the triangle formed by the Laredo, San Antonio, and Corpus Christi metropolitan areas. The uranium mining industry, in fact, has been the major dynamic element in this rural area despite relative stagnation in most of the region's other basic economic sectors. Over the three years from 1976 to 1978, the South Texas uranium mining industry directly contributed a total of $115 million to the economy of the seven- county region in which it operated and $164 million to the economy of the entire state of Texas. In 1979 alone, the total direct contribution of the industry to the Texas economy had climbed to $124 million in personal, business, and government income. PERSONAL INCOME IMPACT In the period from 1976 through 1978, the South Texas uranium mining industry provided an average of $12.5 million in personal income each year directly to residents of Atascosa, Bee, Duval , Karnes, Live Oak, McMullen, and Webb counties -- the seven Texas' counties that make up the South Texas Uranium Belt. A1 though 84 percent of this resulted from the employment of area residents in uranium industry jobs, some amounts were also provided by the payment of rents and royalties to land owners for the use of their land and mineral rights in uranium mining operations. In 1979, the uranium industry provided approximately $38 million to residents of the Uranium Belt and the rest of Texas. This was more than double the average of $16.1 million provided to Texas residents during the 1976 to 1978 period. The full importance of the uranium industry as a source of personal income, however, should not be reckoned merely by the amount of wages and salaries that it pays directly to its own employees, nor by its rent and royalty payments paid directly to land and mineral rights owners living in Texas. The added payments that the industry makes directly to other Texas businesses and state and local governments in Texas are themselves converted into personal income as those business firms and government units in turn pay their employees. All of the direct income payments made by the uranium industry circulate and recirculate within the state's economy, multiplying their impact as they go, until they eventually all leak out of the state as federal taxes or as payments to individuals or businesses located outside of Texas. The combined circulation and recirculation of the direct personal, business, and government income that was provided by the-uranium industry in Texas during 1976, 1977, and 1978 resulted in an average annual amount of indirect personal income of more than $83 mill ion. This alone was $20 mill ion more than the industry's average annual sales during the same years. The total of combined direct and indirect personal income contributed to the Texas economy by the uranium mining industry in that same three-year period thus averaged almost $100 million annually. In 1979, the amount of indirect personal income contributed to the Texas economy by the circulation of uranium mining's direct contributions had risen to about $196 million, more than double the average of the previous three years. The combined direct and in- direct personal income impact in 1979 thus amounted to $234 million. BUSINESS INCOME IMPACT The income provided directly to other Texas business firms through the purchase of needed goods and services by the uranium industry has been twice as big as the industry's payrolls. In 1976, 1977, and 1978, the South Texas uranium industry spent an average of almost $36 million each year to buy both goods and services from other Texas businesses. By 1979, this direct contribution to the Texas economy had swollen to $76 million. The biggest share of the uranium industry's payments to other businesses have gone to contracting firms, including both construction firms and those providing specialized mining services. In the past four years, about 40 percent of the direct payments made by Texas uranium producers to other Texas firms have been to contractors. Texas wholesale and retail firms have also shared in the business sales provided by the South Texas uranium mining industry. Over the past four years, Texas wholesale and retail trade businesses have accounted for about 34 percent of the uranium mining industry's purchases from other Texas businesses. Public utilities firms have received another six per- cent, while Texas manufacturers and transportation firms have accounted for about five percent each. The other sectors of the state's economy, including other mineral industries, agriculture, finance, insurance, real estate, and services, have accounted

Jan 1, 1980

By J. F. Peters

The term solution loss is discussed and defined. Examples are given showing that solution loss may either have a favorable or unfavorable effect on blast furnace performance. A theory is advanced explaining the contradictions encountered during earlier studies of the problem. MANY papers have been written and numerous theories advanced concerning the chemical reactions in the iron blast furnace. Richards, discussing the utilization of fuel in the blast furnace, said: "All the carbon burnt in the furnace should be first oxidized at the tuyeres to CO and all the reduction of oxides above the tuyeres should be caused by CO, which thus becomes CO,. This dictum is not Gruner's own words, but expresses their sense, and from the point of view of the present discussion, it is the correct principle upon which to obtain the maximum generation of heat in the furnace from a given weight of fuel." Richards also said the cubic feet of wind per pound of coke does not express how efficiently a furnace is running, but it will be shown later where Howland paid much attention to this figure. Richards pointed out a shortcoming of Grun-er's discussion in that Richards claimed there is not enough CO generated in a good working blast furnace to possibly combine with the oxygen of the ore, so some of it must be reduced by solid carbon. Mathesius2 made two important contributions. First, he wrote the direct and indirect reduction equations showing the heats of formation in each case and stressed that the indirect reduction reaction produces heat while direct reduction absorbs heat. Secondly, he substantiated Richards' conclusion that there may be a deficiency of CO gas and that some direct reduction is required, but he pointed out that "direct reduction in the hearth has often been confused with direct reduction in the stack, which more correctly should be termed 'premature combustion'." Then he said that "as this carbon is consumed partly by economical (direct reduction in the hearth) and partly by wasteful reactions in ever varying proportions, it is evident that the relation of this total carbon gasified above the tuyeres to the fuel consumption of a furnace cannot possibly have a direct bearing on the economy of furnace operation. The premature combustion of carbon (CO2+C?2CO) must therefore in all cases be considered a detrimental reaction." Johnson3 discussed this whole problem. Through experience Johnson found that when departure from Gruner's ideal working is considerable, the fuel economy is poor, and when the quantity of blast goes up, the fuel economy goes up in the same proportion. Johnson said that the wind per pound of coke is a measure of fuel economy, which will be shown to be wrong. Howland4 established the fact from operating data that there was no relationship between the coke consumption of a furnace and the percentage of coke burned at the tuyeres. But some of his calculations have led to questionable conclusions, such as "it is practically impossible to obtain low coke consumption unless we keep our wind low." Howland made an important contribution when, in his concluding paragraphs, he reached certain negative decisions as to why one coke works better than another. He said the reason one coke works better than another in a blast furnace is not because: 1—there is any difference in the percentage gasified at the tuyeres, or 2—there is any difference of wind required per pound of coke. Korevaar5 propounded a new theory on combustion which disagrees with Gruner because "as far as we can see, this is sufficient proof for the invalidity of Gruner's ideal, for if it was valid, the Low coke consumption should always be accompanied by a higher percentage of carbon burned at the tuyeres. This not being the case, we must deliberately give up our belief in Gruner's ideal." The part in italics will be proved to be wrong. Martin" contended that there was not enough reducing capacity in the blast furnace unless solution loss occurs. He came to a series of conclusions, such as: 1—The greatest efficiency of the blast furnace may not be attained when the reduction is performed entirely by carbon monoxide as demanded by Gruner's definition of the ideally perfect working of the blast furnace. 2—The so-called solution loss reactions, which should more properly be termed direct reduction reactions, promote furnace efficiency. 3—In modern blast furnace practice, the carbon consumption of the process is determined primarily by the carbon needed for reduction purposes, any thermal deficiency created by the reduction process being balanced in practice by the use of blast heat. From a practical standpoint further discussion of the theory of chemical reactions is of little moment. There is however one phase of the general theory of chemical reactions which is very important and that is the combustion of coke in the blast furnace. The purpose of this paper is to show that the reaction

Jan 1, 1955

By C. S. Finney, John Mitchell

The growing popularity in the United States of the vertical-flue even was emphasized when in 1905 the United States Steel Corp. chose the Koppers oven as the type which best suited their requirements. Heinrich Koppers was born on November 23. 1872. at a small farm in Walbeck near Geldern on the lower Rhine. When young Koppers was eight years old, however the family moved away from the farm to the industrial city of Bochum in the Ruhr. Here Koppers attended public school and subsequently served an apprenticeship to a tinsmith before taking a job as a lathe operator with a local steel company. He had ambitions to be much more than a machinist, however, and used his week-ends and evenings to improve his theoretical background by taking courses at a vocational-training school in Bochum. After winning the highest honor the school could bestow (the silver Staats-medaille), Koppers went on to continue his education at the Rheinisch-Westfalische Hüttenschule in Duisberg. One of his teachers there, Fritz Wüst who later became a professor at the Technische Hochschule at Aachen, recognizing Koppers' unusual abilities, predicted for him a great future. In 1894 Heinrich Koppers joined the firm of Dr. C. Otto and Co. in Dahlhausen, and in 1899 while superintendent of the Mathias Stinnes mine he built his first battery of ovens for Hugo Stinnes, the German industrialist. Two years later he started his own organization, and in 1902 he made Essen his headquarters. It was to Essen that a group of engineers from the United States Steel Corp. went in 1906 with an invitation to Koppers to design and supervise the construction of four batteries of ovens at the Joliet works of the Illinois Steel Co. Each battery was to consist of 70 ovens. Arriving in the United States in 1907, Koppers established a branch of his firm in Joliet, and construction began. The first battery was fired on July 27, 1908. Rugged and simple, these ovens incorporated basic design features which were to make the Koppers oven and its future modifications the choice of a very large segment of the by-product coking industry of America. The 280 ovens at Joliet were 35 ft long, 8 ¾ ft in height, and tapered from 21 to 17 in. The total daily capacity of the four batteries was 2240 tons of coke. The ovens were of the new cross-regenerative type; that is, instead of longitudinal regenerators serving an entire battery, as in the older Koppers ovens, cross regenerators for each separate oven were employed. Fuel gas was supplied from the side of the battery through ducts in the brickwork known as gun flues, which reached to the center of the battery under the vertical heating-flues. Removable, ceramic gas-nozzles fitted at the top of each gun flue helped to insure good control over the distribution of the fuel gas, and uniform heating conditions were also promoted by regulating the air supply to, and the suction in, each heating flue. A different refractory w& used for each battery. One was built of American silica brick, one of American quartzite, and two of imported German quartzite. The installation at Joliet proved to be very successful, and in 1911, 490 additional' Koppers ovens were built for the Illinois Steel Co. at the great new steelworks at Gary, Ind. By 1912 the H. Koppers Co. had established its headquarters in Chicago and was rapidly extending its business to include construction for such iron and steel companies as the Woodward Iron Co. at Woodward, Ma. (80 ovens in 1912); the Tennessee Coal, Iron and Rail- road Co. at Fairfield, Ala. (280 ovens in 1912); the Inland Steel Co. at Indiana Harbor, Ind. (86 ovens during 1913 and 1914) ; and the Republic Iron and Steel Co. at Youngstown, Ohio (68 ovens in 1913). In 1914 a group of men in Pittsburgh bought a major shareholding in the H. Koppers Co., and moved the headquarters of the organization from Chicago to their own city. Under its new management the company was highly successful in obtaining a large share of the contracts for by-product installations built during World War I. In 1917 the remaining German interests in the company were

Jan 1, 1961

Application of technology to the search for new deposits went on apace in 1963. Traditional methods, aided by modern communications, were successful in some out-of-the way corners of the world that had not been adequately prospected, but the co-ordination of several mutually supporting techniques is necessary to define exploration targets in most areas today. Although these obviously include geophysics and geochemistry, which are treated elsewhere in this issue, geology continues to play a major role. As the search focuses on less and less obvious targets there will be more need than ever to "pull out all the stops." Any anomaly may have significance and must be evaluated as a possible lead. Ability to detect them increases as the laboratory workers refine techniques for measuring physical, chemical, and isotopic properties; it will be increasingly the responsibility of the exploration geologist to understand and apply these to economic problems. Simple propecting, the search for outcrops of recognizable ores of traditional types, was perhaps most successful for iron. Potentially large deposits of high-grade magnetite-specularite-hematite ore have been found in the Mary River area near the north end of Baffin Island. The ore holds up four hills that stand some 1500 ft above the surrounding country; obviously they were ripe for discovery by the first person to come across them, in this case Murray Watts, president of British Ungava Explorations, Ltd, As preliminary examination indicates a lump ore averaging 68 to 70% iron, these deposits may be commercial in spite of the unfavorable climate and their isolation from world markets.

Jan 2, 1964

E. C. Pechin, Cleveland, 0.: Will you indulge me a moment, Mr. President, to narrate an incident which is recalled by your admirable address?

Jan 1, 1895

By D. B. Jugle, J. B. Darby

The equilibrium solubility limits of the transition elements Ti, V, Cr, Fe, and Co in liquid tin were determined in the temperature range from 827" to 1211°K. Since the equilibrium concentration of Ti, V, or Cr in liquid tin is moderately dilute in the temperature range investigated, the solubility data were employed to estimate the partial molar enthalpy and the partial molar excess entropy of solution for the three solutes in liquid tin. The reference state s for titanium or vanadium were selected relative to the solute in an intermetallic compound. The thermodynamic quantities for chromium were calculated relative to pure chromium. RECENT experiments1 have shown that the rate of solution of several transition elements in liquid aluminum can be qualitatively predicted from a knowledge of the temperature dependence of the solvent-rich liquidus. In order to extend the analysis to binary tin systems,' it was necessary to know the equilibrium solubility of several of the first-long-period transition elements in liquid tin. Since solubility data for the tin-rich portion of binary systems are meager, the present investigation was undertaken to determine the equilibrium solubility limit of Ti, V, Cr, Fe, and Co in liquid tin in the temperature range from 850" to 1200°K. EXPERIMENTAL PROCEDURE A useful technique3 to determine the equilibrium solubility of a solute in a liquid-metal solvent consists essentially of placing a pure solute in contact with a pure solvent and allowing sufficient time for equilibrium to be attained at the temperature of interest. Subsequently, the solvent is removed and the equilibrium solute concentration in the solvent is determined by an appropriate analytical procedure. The technique can be applied very successfully to relatively simple systems such as the copper-germanium system.3 However, in many binary systems of transition elements with tin, several intermediate phases are known to exist and precipitation of the phases from solution, in solubility experiments, can lead to an erroneously large solubility. The difficulty was avoided in the present work by equilibration of the most solvent-rich intermediate phase with the pure solvent over a range of temperatures. The compounds employed in this investigation, and the temperature range over which each compound is in equilibrium with liquid tin are listed in Table I. No stable intermediate phases are reported in the chromium-tin system4 and, therefore, pure chromium was utilized as the solute. The stoichiometric compounds were prepared by arc-melting on a water-cooled copper hearth in a helium-argon atmosphere. The elemental tin employed in.this investigation was 99.998 pct pure, and typical lot analyses of the transition elements were reported elsewhere.' A sample of an appropriate solute, in the form of a button and in sufficient quantity to exceed the equilibrium solubility, and the pure tin solvent were placed in a high-purity recrystallized-alumina crucible. The crucible and contents were placed in a horizontal furnace under a high vacuum (10-6 torr) and held at temperature for periods varying between 24 and 72 hr. A water-cooled quench tank, partially filled with diffusion-pump oil, was attached close to one end of the

Jan 1, 1970

By Nicholas J. Grant, Italo S. Servi

THE creep and stress rupture properties of three grades of aluminum have been reported in a previous paper.' It was found that the stress coefficient of the creep rate and of the rupture time changes at the transition from low temperature-type to high temperature-type deformation. The transition corresponds to the equicohesion for grains and grain boundaries. In order to support the conclusions obtained from the examination of creep and stress rupture data, the deformed specimens were observed metallographically and a few special tests were conducted. The results of these qualitative observations are given in the present paper. Experimental Procedure and Results Table I gives the types of aluminum specimens.' The creep and stress rupture tests were conducted in simple tension at constant stress. Further details on the experimental techniques have been given.' The test bars were electropolished in a perchloric-acetic mixture before testing and were observed after testing without any further preparation unless otherwise specified. Observations of specimen cross-sections were made after electrolytic polishing and etching. The samples were extended along a direction parallel to the longer side of the micrographs of Figs. 12 through 27. The log-log plots of stress vs. minimum creep rate for the three grades of aluminum appear in Figs. 1 and 2. The reference numbers on each curve help relate the photographs to the conditions of testing, indicating where high temperature-type deformation and failure prevailed and where low temperature behavior prevailed. Deformation of Single Crystals at Very High Temperature: An annealed, high purity aluminum specimen was slightly strained at one end and re-annealed. A large single crystal was formed at the strained end of the specimen during re-annealing; the other end remained polycrystalline (see Fig. 3). A stress of 50 psi was applied to the cold specimen to avoid loading at 1100°F. The temperature was then raised to 1100°F, kept at 1100°F for 3 hr, and lowered again to room temperature. Fig. 4 shows the appearance of the specimen after testing. The single crystal deformed by gliding along parallel planes, while the polycrystalline part deformed mainly by grain boundary flow. Some grain growth occurred in the polycrystalline part. Another high purity specimen, which had two large single crystals at the two ends and a polycrystalline zone in the middle portion, was tested at 1000 °F under a stress of 100 psi. The appearance of the sample after test is shown in Fig. 5. Even though considerable slip occurred in the single crystals, the fracture occurred in the weaker polycrystalline portion. Evidence of Grain Boundary Migration during Creep Testing: A high purity, coarse grained specimen, which had a large crystal in the middle portion (see Fig. 6) was tested at 700°F under a constant stress of 175 psi for 30 hr. The appearance of the specimen after testing (Fig. 7) indicates that the large crystal deformed by gliding along parallel planes, while the rest of the specimen deformed mainly by grain boundary flow. Microscopic examination showed clear evidence of grain boundary flow and grain boundary migration, an example of

Jan 1, 1952

By AIME AIME

PERHAPS the most interesting paper of the subsidence session on Monday morning was that by Roland D. Parks entitled "Yieldable Metal Props for Underground Support." This paper described the development of a telescoping prop made from two pieces of pipe. The lower and larger in diameter has cast in it a soft metallic alloy which is slowly extruded through an orifice in the upper and smaller piece of pipe. In this way, the length of the prop decreases gradually as the load from the roof increases. The stress-strain diagram for these props, as tested in the laboratory, is almost ideal, and can be duplicated satisfactorily in successive tests. They have not yet been tested underground. Another paper of much interest was presented by Prof. P. B. Bucky. It is an addition to his series on structural models as applied to mining and was entitled "Effect of Approximately Vertical Cracks in the Behavior of Hori¬zontally Lying Roof Strata." It was illustrated by motion pictures of a model under test. After explaining the un¬derlying theory, the apparatus and the mode of testing, Prof. Bucky set forth the effect of vertical cracks in a mine roof, as follows: (a) the wider the crack, the weaker the roof; (b) where the sides of the crack are in juxtaposition, there is little weakening of the roof; (c) grouting cracks whose sides are not in contact restores the strength of the roof until it may be as strong as, or stronger than the uncracked roof. Small paper props helped sustain the roof. Both the nature of the material and its bonding affect its behavior under stress.

Jan 1, 1933

By T. A. Rickard

The purposes of composition are various; one purpose, for instance, is to make a record for the writer's own use, as in a diary. That does not involve responsibility to others. There is also the writing meant to influence opinion-to be persuasive, and pleasing. With such writing we need not concern ourselves at this stage of our study. The prime purpose of technical writing is to be informative-to convey information; therefore it must" be clear beyond the chance of misunderstanding. Such clearness is impossible if meaningless or ill chosen, words are sprinkled through the text. Discard the trivial phrases that are constantly at your elbow. Brush aside a host of vapid superlatives. Metternich exclaimed:' "The superla¬tive is the mark of fools". It is a false emphasis, like the underlining in a school-girl's letter. For example, the little word `very' can be deleted nine times out of ten; it is an impediment to terse and perspicuous writing, as 'the multitudinous hand-baggage of the British tourist is to his travel. 'Very' supposes comparison. A mine with a 1000-ft. shaft is very deep to the scribe who writes from the Joplin district', in Missouri, but it seems a shallow hole to a man living at Calumet, Michigan. A vein that is 10 feet across may be considered very wide at Cripple Creek, Colorado, but it is only a `stringer' to the miner at the Homestake, in South Dakota. Ore assaying $20 in gold is very rich at Juneau, Alaska, where .10,000 tons of $1 ore is crushed daily, but it is relatively low-grade to the pocket-miner at Alleghany, in California. It is all a matter of comparison; unless the reader knows your standards of depth, width, or richness, your `very' has no significance. "Where erosion was very rapid or oxidation very shallow"

Jan 1, 1931

By Carl F. Floe, John Chipman

A YEAR ago the authors published a paper on the solubility of sulphur dioxide in molten copper.1 The data in that paper agreed closely with that obtained by previous investigators, which, however, did not agree with the theoretical predictions for solubility of triatomic gases of this type. It has generally been assumed that the reaction of solution is: [ ] Neglecting the slight change in copper concentration and considering that the concentrations of sulphur and oxygen are both proportional to the volume of gas absorbed, it follows that this volume should be proportional to the cube root of the pressure. It was found that a plot of the volume absorbed versus the cube root of the pressure gave a straight line, but that this line did not pass through the origin. Calculations of the equilibrium constant for the reaction showed that it was fairly constant for pressures above l00 mm. but that actually it approached zero at lower pressures. The conclusion was made therefore that the solubility as determined could not be expressed by Eq. I or by any other simple equation, particularly at low pressures. Other investigators have concluded that the solubility of sulphur dioxide in copper as well as in several copper alloys is more nearly proportional to the square root of the pressure.* Such a conclusion, however, does not satisfactorily account for the results, even when rather complicated mechanisms for the solution are assumed. The highly improbable speculations of Lepp2 and of Schneider and Esch3 based upon hypothetical dissociation pressures of Cu20 and (a; 2S dissolved in copper illustrate the type of reasoning that has been used to account for the discrepancy. In the discussion of the previous paper, the authors pointed out that the discrepancy might possibly be due to impurities in the copper, although the purest form available was used. Further consideration of the problem suggested that the impurities likely to have the greatest effect on the solubility of SO2 in copper were oxygen, sulphur and carbon. Accordingly, further experiments have been made to show the effects of these elements. EXPERIMENTAL METHODS The apparatus used for measuring solubility was essentially the same as that shown in the previous paper. However, since it was desired to make measurements at low pressures, a McLeod gauge was added and 6-mm. glass tubing was substituted for the capillary. This increased the "hot volume" considerably but was necessary in order to obtain good vacuums in a reasonable length of time. A mercury diffusion pump was also installed.

Jan 1, 1942