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Jan 1, 1967

Jan 1, 1903

By G. C. Kuczynski

Two particles in mutual contact form a system which is not in thermo-dynamical equilibrium, because its total surface free energy is not a minimum. If such a system is left for a certain period of time, the bonding of the two particles will take place in order to decrease the total surface area, even though the temperature is lower than the melting point. This phenomenon of bonding of two or more particles with the application of heat only and at temperatures below melting point of any component of the system will be called sintering, although the powder metallurgists use this term in a broader sense, including the presence of molten phase and pressure. It is the objective of this paper to study this process and the mechanisms involved in it. This problem is of utmost importance to powder metallurgy and powder ceramics, and its technological aspects have been studied for a good many years. However, the powder metallurgical operations are too complex and include too many superimposing mechanisms, and too many variables for a direct study. It was therefore advisable for the purposes of this study to reduce the variables to a minimum. In this work the radius of the interface formed during bonding in a simple system composed of a spherical particle and a large block of the same metal was studied as a function of time and temperature. It is believed that the mechanism involved in this simple process is fundamental to any sintering operations. Previous Work J. Frenkell was the first to make a serious attempt to develop a theory of sintering. He assumed that the process consists of a slow deformation of crystalline particles under the influence of surface tension which reduces to a viscous flow where the coefficient of viscosity n is related to the self-diffusion coefficient D by the following equation 1 _ D D6kT [1] where 6 is interatomic distance, k the Boltzman constant, and T the absolute temperature. This type of viscous flow of a crystalline substance is essentially different from the ordinary plastic flow. The latter is a specific propcrty of crystals and cannot take place in amorphous bodies. According to Frenkel this viscous type of flow is due to the diffusion of the holes or vacancies arising in the lattice. He was able to derive an equation relating the growth of the interface between two spherical crystalline particles or between a particle and a semi-infinite crystal (Fig 1) to time t at constant temperature. This relationship can be written as follows: x²— 3/2 a/nt [2] where x is the radius of the interface assumed to be circular, a the original radius of the sphere and a surface tension of the material. The other assump- x tions are that x is less than 0.3 and that during the period 1 the original radius, a, of the metallic particle did not change appreciably. A. J. Shaler and J. Wulff2 followed closely the ideas of Frenkel in their theory of sintering of a mass of metallic powder. Neither Frenkel nor Shaler has validated his theoretical speculations with conclusive experimental data. Two measurements reported by

Jan 1, 1950

By E. H. Bunce

CONTINUED progress in zinc metallurgy has been shown during 1933 by the adoption of new methods as well as the modernization of old processes and equipment, and by the initiation of new fields of activity for future advancement. The use of suspension roasting continued to grow as its advantages and adaptability became increasingly, apparent. The process developed by the National Smelting Co., Ltd., several years ago, of completely roasting on large sintering machines with utilization of the gas for acid manufacture has worked so successfully that an additional machine was installed during the year. At both the Swansea and the Avonmouth Works all of the ore for smelting is now roasted on the large sintering machines, thereby completely eliminating the old hearth-roasting furnaces. Work continued on obtaining partial purification of zinc ores from lead and cadmium by close control of conditions on the sintering machine, and in a few instances by chlorine additions to the ore before sintering. Ores so treated were either partially roasted or com-

Jan 1, 1934

By Karl J. Dreher, Charles C. Hennig, Gregg A. Scott

INTRODUCTION Theodore Roosevelt Dam is a cyclopean-masonry, gravity-arch dam located on the Salt River northeast of Phoenix, Arizona. Construction of the dam began in 1903 and was completed in 1911. The dam is about 85 m high with a total reservoir capacity of about 1.7x109 m3. Raising the dam is now being considered to provide additional water storage and flood control. This paper describes preliminary analyses performed to assess foundation stability for increased loading resulting from raising the dam and reservoir water surface about 12 m. The foundation of Theodore Roosevelt Dam consists of variably metamorphosed limes tones, sands tones, mudstones, and shales. Bedding uniformly strikes nearly normal to the river (N 40º W) and dips upstream at 25 to 30º. The rock is cut by four prominent joint sets as indicated by the joint contour diagram shown in figure 1A. The diagram was developed from surf ace observations and vertical drill core oriented relative to the bedding. Sampling biases account for the differences in concentrations of various joint sets. However, field observations indicate that all sets are relatively prominent, planar, and continuous. SEEPAGE ANALYSES Consistent with practice at the time of construction, no foundation drainage was installed at Theodore Roosevelt Dam. Finite element seepage analyses were therefore performed to study the potential for large uplift pressures in the foundation. The dam has steep abutments and is curved in plan as shown in figure 1B. The effects of modeling the seepage two-dimensionally, radially symmetric about the dam's axis center, and three-dimensionally were therefore com-

Jan 1, 1982

By Sidney Sigel, J. Gardner Brooks, Irvin R. Kramer

In 1942 Grossmannl proposed that the hardenability of a steel may be calculated from its chemical composition by considering the base hardenability associated with its carbon content and grain size and multiplying this base by factors for each element present. Since Grossmann's original publication, several investigaton2-6 have reexamined the multiplying factors for the individual elements and in general have found that the multiplying principle is valid. However, some of the individual factor curves developed have been in poor agreement. Inasmuch as the carbon-factor curve obtained by Grossmann was dependent Lipon the factors for all the other alloying elements present in the steel, it logically followed that his results were in need of correction in the light of the new data available for manganese, silicon, and the other alloying elements. Furthermore, in order to avoid the possibility that errors in the manganese, silicon, or other curves might influence the carbon-factor curve, investigation of iron-carbon alloys containing little or no manganese and silicon was necessary. That the effect of carbon on hardenability was greater than indicated by Grossmann is shown by a comparison of the diameters of completely hardened rounds of iron-carbon alloys with the ideal critical diameter calculated from Grossmann's factors. These alloys have a greater hardenability in a finite quench than predicted by Grossmann's factors for an infinite quench (Table I). Among the other important variables that were in need of further investigation were the effect of deoxidation practice on the grain-size correction curves and the effect of stable carbide-forming elements on the depth of hardening. Most Of the work by Kramer, Hafner, and Toleman4 was done on silicon-killed steels. It was not known whether Gross-mann's grain-size correction curves, determined on aluminum-killed steels, was valid when applied to steels with different deoxidation practice. More data on the

Jan 1, 1947

By J. Gardner Brooks, Sidney Sigel, Irvin R. Kramer

In 1942 Grossmannl proposed that the hardenability of a steel may be calculated from its chemical composition by considering the base hardenability associated with its carbon content and grain size and multiplying this base by factors for each element present. Since Grossmann's original publication, several investigaton2-6 have reexamined the multiplying factors for the individual elements and in general have found that the multiplying principle is valid. However, some of the individual factor curves developed have been in poor agreement. Inasmuch as the carbon-factor curve obtained by Grossmann was dependent Lipon the factors for all the other alloying elements present in the steel, it logically followed that his results were in need of correction in the light of the new data available for manganese, silicon, and the other alloying elements. Furthermore, in order to avoid the possibility that errors in the manganese, silicon, or other curves might influence the carbon-factor curve, investigation of iron-carbon alloys containing little or no manganese and silicon was necessary. That the effect of carbon on hardenability was greater than indicated by Grossmann is shown by a comparison of the diameters of completely hardened rounds of iron-carbon alloys with the ideal critical diameter calculated from Grossmann's factors. These alloys have a greater hardenability in a finite quench than predicted by Grossmann's factors for an infinite quench (Table I). Among the other important variables that were in need of further investigation were the effect of deoxidation practice on the grain-size correction curves and the effect of stable carbide-forming elements on the depth of hardening. Most Of the work by Kramer, Hafner, and Toleman4 was done on silicon-killed steels. It was not known whether Gross-mann's grain-size correction curves, determined on aluminum-killed steels, was valid when applied to steels with different deoxidation practice. More data on the

Jan 1, 1947

By A. L. Barnes

Residual oil in watered-out reservoirs is a tremendous reserve which has been unrecoverable by established production methods. A study of the new recovery methods indicated that the forward combustion urocess might- recover oil from such reservoirs; however, no thermal recovery operating experience in a watered-out system was available. The Delaware-Childers pilot thermal test was undertaken to test the feasibility of thermal recovery in this watered-out reservoir. The pilot test consisted of a 2.22-acre, inverted five-spot in the 600-ft deep Bartlesville sand. The reservoir in the pilot area had a porosity of 20.6 per cent, a permeability of 118 md and an average sand thickness of 45 ft. The reservoir contains a 33' API, 6-cp oil. Combustion was started Nov. 22, 1960. The initial air injection capacity was 750 Mscf/D, but it was eventually increased to 2,000 Mscf/D. The test was surrounded by an active water flood; therefore, water production was initially high, but decreased as the heat wave moved toward the producing wells. Oil-bank arrival at an individual well was indicated by a drop in GOR and WOR, and an increase in oil production. Combustion-front arrival was evident at three of the pilot producers, and they were plugged. Cumulative oil production from pilot area wells war over 12,000 bbl. Operational difficulties were negligible and only conventional equipment was necessary. The combustion efficiency of this test averaged over 80 per cent. Results from coring showed that the leading edge of the combustion front tended to be wedge-shaped but a nearly complete sweep of the reservoir was eventually obtained. An isopach map based on evidence from 10 core holes and the existing wells showed that 126 acre-ft had been swept by the heat wave. Using this swept volume, an air requirement of 15.7 MMscf/acre-ft was calculated. It was calculated that 275 ,STB/acre-ft was consumed bv the heat wave. INTRODUCTION There is a large amount of oil remaining in reservoirs that have been water flooded. A study of ways to recover this oil showed that the forward combustion process might be applicable. Results from a number of forward combustion tests have been reported in the literature, but none of these tests were conducted in a watered-out system. The Delaware-Childers pilot thermal test was initiated in 1960 to define the operating characteristics of underground combustion in this watered-out Bartlesville sand reservoir, The purpose of this paper is to present the pilot test results in detail. FORWARD COMBUSTION PROCESS The forward combustion process consists of initiating combustion in the formation surrounding an injection well and driving this heat wave through the formation toward offset producing wells. As the combustion front progresses through the reservoir, oil and formation water are vaporized, driven forward in the gaseous phase, and recon-densed in the cooler part of the formation. These distilled liquids, water of combustion and gaseous combustion products, form a bank or three-phase region ahead of the burning front. This bank pushes mobile reservoir fluids toward the production wells. The rate of movement of the combustion front is controlled by the rate at which the nondistill able residue which serves as process fuel can be completely burned off the sand. The production performance from a heat wave conducted in a watered-out oil reservoir will differ from one conducted in a dissolved gas-depleted reservoir because of the difference in fluid saturations. The primary depleted reservoir contains connate water saturation, relatively high oil saturation and some gas saturation. The watered-out reservoir contains a highly mobile water saturation, residual oil saturation and little gas saturation. As the combustion front moves forward in either type of depleted reservoir, it drives the distillable oil, the water in place and the water of combustion ahead, and burns the nondistillable portion of the oil. The heat-wave process in a watered-out reservoir differs from the process in a

Jan 1, 1966

By R. P. Marshall

This note describes positive evidence that hydrogen in titanium alloys diffuses under the influence of a thermal gradient. The experiments confirmed the expected similarity of this system to the H-Zr system and produced qualitative information on the magnitude of the heat of transport for hydrogen in titanium alloys. This effect has practical importance in applications where titanium alloys operate in a thermal gradient under conditions such that hydrogen embrittlement may develop within the expected lifetime of the structure, for example in supersonic aircraft service. The theories of thermal-gradient diffusion may be found in recent reviews and experimentation in this field by Shewmon,1 Sawatzky,2 Markowitz,3 and Darken and Oriani.4 The basis for Soret thermal diffusion is the "heat of transport", denoted by Q*. This is an energy term for the amount of heat (energy) transferred by atomic diffusion, and can be either positive or negative signifying a driving force for atomic diffusion to the cooler or hotter region, respectively. Experimentally, Q* is determined by plotting the natural logarithm of the point-to-point concentrations after exposure to a thermal gradient vs the respective point-to-point temperatures in units of the inverse absolute temperature scale. The slope of the straight line is Q*/R, R being the gas constant. For the titanium experiments, specimens (3 by 1 by 1/16 in.) of a) commercially pure titanium, b) the 8 Al-1 Mo-1 V titanium alloy, and c) the 6 A1-4 V titanium alloy were exposed to thermal gradients of 6° to 115°C per in. for 18 days at 250° to 550°C. The temperature gradient was in the direction of the 3-in. dimension. The hydrogen concentrations existing after exposure were determined on sections of the specimens by vacuum extraction. Three sections of unexposed sheet of each alloy were analyzed as standards to allow a check for hydrogen

Jan 1, 1965

Total U.S. mineral production reached an estimated $17.8 billion for 1960, 4 pct above 1959 and second only to the record high of $18.1 billion established in 1957. As a group, metals achieved a rise from $1.6 billion in 1959 to $2.0 billion this year, an increase of 28 pct. Similarly the value of nonmetallic production including fuels (i.e., natural gas, petroleum, natural-gas liquids, asphalt and related bitumens, carbon dioxide. anthracite. bituminous and lignite coal, peat, and helium) rose from $15.5 billion in 1959 to approximately $15.8 billion in 1960. However, this 2 pct increase in the total value of non-metallic production was due to an increase in the value of the fuels ($11.8 billion in 1959 to $12.2 billion in 1960) which offset a drop in value of the other nonmetallic minerals ($3.7 billion in 1959 to $3.6 billion in 1960).

Jan 2, 1961

By J. Blodget Britton

During the last three or four years I have had occasion to examine, chemically, various samples of matter commonly called flue-dust or cinder, found deposited in the flues and hot-blast chambers and under the boilers of blast furnaces, and also in the flues and under the boilers of puddling and boiling furnaces. Recently several of these examinations mere made quite in detail, and as the results reveal, I believe, information of no inconsiderable importance, I am induced to communicate them to this Institute. A sample of deposit obtained from the flues of one of the blast furnaces at the works of the Phœix Iron Company, at Phœnixville, Pa., was found to have the composition given in Column I of the following table: I. 11. 111. Composition of Dust from Dust from Dust from Deposits. Blast Furnace. Puddling Furnace. Boiling Furnace. Protoxide of iron,... 1.51 3 08 1.18 Peroxide of iron,... 20.21 33.29 41.00 Alumina,....6.57 12.89 7.54 Lime,.....3.98 .48 .61 Magnesia,.....69 .09 .19 Protoxide of manganese,. . 1.66 .39 .12 Oxide of zinc,....2.84 ........ Oxide of copper,. .. ..06 ........ Silicic acid,....36.00 40.69 38.99 Sulphuric acid,... 7.55 .43 Phosphoric acid,..94 ..94 Arsenious acid,. .. .38 Antimoniousacid,... trace.......... Chlorine,....03 ..03 Cyanogen,.....09 ........ Ammonia,.... trace......... Pottlsh with some sodn,. .. 16.61 ........ Carbonic acid,. .. .. .59 ........ Alkalies, undetermined matter, and loss,.......29 4.49 6.96 100.00 100 00 100.00 Metallic iron,. 16.31 25.70 29.64 Phosphorus,. .. .. .41* 1.55† 1.30†

By Cresap P. Watson

ABOUT the time this magazine reaches its readers, Cresap P. Watson will celebrate his 53d birthday. If he spends that birthday at his West Los Angeles home, he won't be far, as distance is measured today, from Santa Barbara, where he was born on July 8, 1895. He is truly a member of a petroleum family; one brother, N. O. Watson, managed Royal Dutch Shell interests in Venezuela for years and is now general manager of the Caribbean Petroleum Co. at. Maracaibo; another brother, Rex, is vice-president of the Drilling and Exploration Co., while brother-in-law Ben Belt is an executive of Gulf Oil. His own life has centered in the petroleum industry since his first job in 1913 as camp cashier for a Mexican oil field at Tampico. Down on the isthmus of Tehuantepec he advanced to tool dresser and' production foreman for the company. The first World War interrupted his Mexican experience by transforming him into an artillery officer in France. Once the Army ceased to demand his services¬by then it was 1919-he returned to the task of furthering his professional career as agent for the Amerada Petroleum Corp. By 1927 he had reached the position in which he could be called an executive in the petroleum industry, having organized and become president of the Federal Royalties Co. His activities in local and national legislation affecting the petroleum industry increased as has his advocacy of the development of oil and gas fields under sound engineering and conservation principles through unitization or other co-operative forms of operation. Considerable amounts of his time go to the promotion of industry public relations.

Jan 1, 1948

By A. M. Ribe

Briefly stated, the mission of the traffic manager (currently called a transportation services manager) is to enable his firm to utilize to its best economic advantage the various systems and modes of transportation available to it to bring in its raw materials and ship out its finished products. The function of the transportation services manager is perhaps of more relative importance in industrial minerals operations than in industry and trade generally.

Jan 1, 1970

Mining and oil industry representatives are scheduled to testify May 15 at hearings on the Simpson bill to extend the Reciprocal Trade Agreements Act, Several Congressmen have introduced bills to extend present trade agreements without modification. Price of copper appears to be stabilizing at 30[] per lb, after a period where market price ranged from 27 to 34[]. Copper offerings from abroad were finding no takers at 30.24[] per lb late in April.

Jan 5, 1953

By William Mikulas

LITTLE work has been done in the field of the nickel-tin binary system. The complete diagram has been investigated on two occasions, but the results are in very poor agreement. The structure of a compound NiSn, and the solubility of tin in nickel have been determined by X-ray methods. Several investigations have been made of the liquidus curve, and the compositions of the eutectics have been determined. A study of the literature, however, shows that there is no satisfactory agreement between the data presented in the various papers. The present investigation was undertaken in an attempt to determine the equilibrium conditions, and to correlate X-ray with metallographic data. The equilibrium diagram was determined by thermal and metallo-graphic means, and the solubility of tin in nickel further investigated with X-rays. Powder diagrams were made of the intermetallic com-pounds, and three of the structures were partly determined. No attempt was made to determine the range of homogeneity of the inter-metallic compounds.

Jan 1, 1937

By V. Niemitz

Approximately 30 miles east of Chicago on the southern shores of Lake Michigan stands Bethlehem Steels newest fully integrated steelmaking facility-the billion dollar Burns Harbor plant. The first phase of what will ultimately be the most completely integrated and flexible materials handling system for a steel mill in the western hemisphere is now complete.

Jan 1, 1970

By NORMAN D. FitzGkrald

IN 1942 the outstanding characteristic of the petroleum industry was the multiplicity of war-induced distortions in virtually every segment of the business. So devastating was the success of the Nazi submarine campaign along the shores of the western Atlantic and on transoceanic routes that within six months after our entry into the war petroleum rationing was necessary in the East Coast area. The conquest of the Netherlands Indies by the Japanese three months after the opening of the war in the Pacific cut off our normal sources of rubber, and in our first year of war nationwide rationing of gasoline had to be invoked to conserve rubber-borne transportation facilities. Meanwhile the oil industry faced the imperative necessity for rapid expansion in the output of aviation gasoline and later accepted the vast responsibility for developing a new industry. synthetic rubber manufacture. Probably no other essentially peacetime industry has been forced to make so many complicated adjustments, yet its response to its wartime obligations has been nothing short of dramatic.

Jan 1, 1943

Jan 1, 1969

By Robert Franke

In view of the prominence which the conical mill has attained in the fine-crushing field within the few years since its introduction, the following comparison with its more mature forerunner, the Chilean mill, based on extensive tests, is submitted in the interest of the milling profession. Soon after designing the concentrating plant of the Miami Copper Co. in 1909, the Hardinge conical mill made its appearance in the milling forum. Its possibility as a suitable crushing device for the plant was well recognized, but in view of the lack of commercial demonstration, at the time, as to capacity, efficiency for desired product, and the still more uncertain factors of cost of maintenance and power consumption, it was deemed that the immediate adoption of this machine throughout the plant would be a hazardous undertaking. For these reasons it was decided to equip the majority of the immediately required units of the plant with Chilean mills, the fine-crushing proficiencies of which were better known, and one section with Hardinge mills, to serve as a test unit for the guidance of future installations and replacements. Thereby, after 1.5 years' operation with both types of mills, a thorough test as to metallurgical efficiency and cost economy has been obtained. The conical mill used in these tests is the 8-ft. Hardinge pebble mill, having a cylinder 22 in. in length. The cylindrical portion of this mill is lined with cast-iron liner plates, and the conical extensions with silex bricks bound together by cement. Each liner plate carries a projecting lifter, the function of which is to increase the height of drop of the lifted material. Danish No. 5 pebbles, obtained from the coast deposits of Denmark, are used for the grinding charge. The Chilean mill used is a fast-running, 3-roller, 6-ft. Saturn mill, with screens of 0.037-in. opening. The feed to these mills is the oversize of Callow screens having 0.029-in. openings, which follow rolls crushing to 0.5 in. For the ore of this mine, a moderately hard but very fissile schist,

Jan 1, 1914

By James B. Cathcart

The potash mine of the International Minerals and Chemical Corp. is about 18 miles east of Carlsbad, New Mexico, in sec 1 and 12, T 22 S, R 29 E, N.M.P.M. Potash is produced from two zones in the Salado formation of late Permian age. The lower zone, consisting of a mixture of sylvite (KCI) and halite (NaCl), lies at a depth of about 900 ft, and the upper zone, in which the principal potassium mineral is langbeinite (K2SO4 2MgSO4), lies at a depth of about 800 ft. Because of the plastic nature of the material, fractures in the Salado formation are extremely rare and have been noted only on the 800 ft level of the International mine. The open fracture described below is almost unique. Only one other open fracture has been noted, and it was on a working face in the same general area as the one described, but was destroyed before the writer had a chance to examine it. According to J. E. Tong, foreman on the 800 level, this fracture was similar to, but smaller than, the one herein described. The saline strata are nearly flat-lying and comprise interbedded layers of halite, anhydrite (CaSO4), and poly-halite (2CaSO4.MgS04.K2SO4-2H2O), with halite predominating. The halite layers contain local concentrations of sylvite, carnallite (KC1.MgCl2.6H2O), and langbeinite. The principal marker in the potash mines area is a bed of anhydrite about 8 ft thick, and 70 ft below the 800 level. This bed contains varying amounts of polyhalite, and locally a few blebs of sylvite. Two principal marker beds are present over most of the 800 level. The lower is the "Middle Salt Marker," a bed of bright-orange halite, which ranges in thickness from a knife-edge to about 0.6 ft, and is usually bounded above and below by thin seams of green or reddish-brown clay. In langbeinite-rich areas, this marker usually contains abundant blebs of langbeinite. The upper of the two principal markers is a green clay seam, containing abundant halite, which ranges in thickness from 0.1 to about 0.5 ft. It is 2 to slightly more than 5 ft above the Middle Salt Marker. No langbeinite of minable grade is found above this clay, and it

Jan 1, 1950