Search Documents

By Jean Herenguel

THE published work of Lacombe and Beaujard' has demonstrated the interesting application of etch figures to the determination of crystal orientations in aluminum by a purely micrographic method. The geometry of these figures leaves no ambiguity and the method has the added advantage of being applicable to very small crystal units. These authors applied the technique to the study of high purity aluminum, and it has now been adopted buy Heren-guel and his collaborators to various researches on commercial aluminum, containing up to 1 pct Fe and Si. This must modify the opinion point,ed out by

Jan 1, 1953

By H. B. Fuqua, B. E. Thompson

The area discussed herein, commonly known as the North Texas district, embraces the following 10 counties: Archer, Baylor, Clay, Cooke, Foard, Hardeman, Knox, Montague, Wichita and Wilbarger. It is undcrlain by two major structural features. The northernmost portion of the district, including Cooke, Montague, northern Clay, Wichita, Wilbarger, Foard and Hardeman Counties, is underlain by the system of buried mountains known as the Red River uplift, which is parallel to and closely related to the Wichita-Amarillo uplift of Oklahoma and the Texas Panhandle. While the presence of a great majority of the numerous oil fields of the area is traceable to this feature, the production

Jan 1, 1938

By K. Kobayashi, K. Ueda, K. Yamaguchi

Lead concentrates from Kuroko (black ore) mines, which contain 4-7% Cu, 55% Pb, 3-777, Zn, and 0.5-0.9% As, are pretreated by a hydrometallurgical process before electric furnace smelting with other lead resources from Kuroko. The hydrometallurgical pretreatment involves sulfuric acid leaching in the first stage and ferric leaching in the second stage. This paper describes the short history of lead recovery from Kuroko and the performance of laboratory tests and pilot plant and commercial operations.

Jan 1, 1985

By J. R. Thoenek S. L. Windes

The amplitudes and frequencies of vibratiolls of a four-story stucco building were measured by specially developed electrocapacitive seismometers. Records were made on three floor levels with as many as 10 seismometers recording simultancously. Sources of vibration were: (1) an electric motor with unbalanced pulley, maximum speed 1800 r.p.m., maximum centrifugal force 90 lb., (2) truck traffic (both solid and pneumatic tires) moving over inequalities in the street in front of the house, (3) falling weights dropped on the street pavement from different heights, (4) miscellaneous sources, including a man jumping on the floor of the house and slamming doors. Tests were made to determine the natural frequencies of floor and wall panels by varying the speed of the unbalanced motor and by exciting the panels with a single impulse. The vibrations recorded were compared to records of vibrations from quarry blasts and it was observed that the vibrations from truck traffic were comparable to those recorded from quarry blasts and in no instance was there any damage to the building. As the tests were all of a negative character as far as damage was concerned, no index of destruction is formulated. Instead, the records are presented simply as vibration measurements obtained in an ordinary house under typical conditions.

Jan 1, 1940

By J. R. Thoenek S. L. Windes

The amplitudes and frequencies of vibratiolls of a four-story stucco building were measured by specially developed electrocapacitive seismometers. Records were made on three floor levels with as many as 10 seismometers recording simultancously. Sources of vibration were: (1) an electric motor with unbalanced pulley, maximum speed 1800 r.p.m., maximum centrifugal force 90 lb., (2) truck traffic (both solid and pneumatic tires) moving over inequalities in the street in front of the house, (3) falling weights dropped on the street pavement from different heights, (4) miscellaneous sources, including a man jumping on the floor of the house and slamming doors. Tests were made to determine the natural frequencies of floor and wall panels by varying the speed of the unbalanced motor and by exciting the panels with a single impulse. The vibrations recorded were compared to records of vibrations from quarry blasts and it was observed that the vibrations from truck traffic were comparable to those recorded from quarry blasts and in no instance was there any damage to the building. As the tests were all of a negative character as far as damage was concerned, no index of destruction is formulated. Instead, the records are presented simply as vibration measurements obtained in an ordinary house under typical conditions.

Jan 1, 1940

By A. D. Hodges

The process to be described, whatever other merits (or demerits) it may have possessed, certainly proved a financial success under the conditions of the locality where it was introduced and where a refining process had been sought previously in vain. I have ventured to bring it to the notice of the Institute in the hope that it may prove of some interest as a solution of a practical problem, such as is often presented to the metallurgist in the remote mining regions of the West. The method was used first at the Lyon Mill at Dayton, Nevada, and has been adopted at other tailings-mills on the Cornstock. These mills treat two classes of tailings: "sand," or; material which has passed previously through the pans of the ore-mills; and " slimes," or the fine clayey material which, coming from the battery, is too light to settle in the tanks inside of the mills but is

Jan 1, 1886

By J. A. Herrick Nashua

IN this country steel made in a Siemens furnace or Bessemer converter, is generally tapped into a ladle or shoe, and then drawn through an aperture in its base into the various moulds. In order to regulate the flow of the molten mass a refractory valve is arranged at the aperture. A plumbago nozzle is fixed firmly in this aperture, and a stopper of like material is fitted to it, making a socket valve. In order to raise and depress this stopper at will, a rod is fastened-to it, extending through, the metal and over the brim of the ladle, where it is bent back in a half circle and secured in a slide. This slide plays vertically in a frame, permanently fastened to the outside of the ladle, and is moved by a lever having as a fulcrum a pin fixed in this frame, one end, of the lever being temporarily fixed to the slide, and the other end being moved by hand. Reference being had to the drawing (see Plate 1, Fig. 1), E is the nozzle, D is the stopper, A is the rod, protected as hereinafter described, C is the cast-iron framework, B is the wrought-iron slide, B' is the offset into which the rod, A, enters, and is secured in the usual manner by a key, a. Section J, K, shows the manner of hanging the lever. J is a pin attached to the slide by which the end of the lever raises the slide, B. J is the fulcrum fastened to the frame, C. K (Fig. 1) is a hand-nut fastening the slide, B, to the frame, C, at will. Fig. 2 is a side elevation of ladle, showing the outside working of the parts above described. It is the common practice to protect the rod, A, by a coating of clay and fire-sand, kneaded to the right consistency and applied to the rod, and then thoroughly dried. Just before casting, the plumbago stopper, D, is heated at its extremity to redness separate from the ladle and, at the moment of pouring, is placed in the ladle and slide, and adjusted as well as practicable. Some very serious defects ensue, causing much trouble and vexation as well as actual loss. The fire-clay coating in drying becomes cracked and seamy, and at its best is more or less loose on the rod. The hot metal sometimes cuts

Jan 1, 1879

By V. R. Garfias R. V. Whetsel

Production of crude petroleum in Mexico during 1935 totaled approximately 40,082,000 bbl., an increase of 1,925,000 bbl. over the previous year. Successful development continued in the Poza Rica field during the year, increasing production in that area from 3,708,000 bbl. in 1934 to 9,542,000 in 1935. The output of the South fields (Golden Lane) area decreased by 3,000,000 bbl. during the year, and the heavy-oil district of the Northern fields by 1,500,000 bbl. Production in the Tehuantepec fields showed a slight gain. Production of natural gasoline increased from 430,000 to 600,000 bbl. in 1935. Crude run to stills in local refineries is estimated at 30,000,000 bbl., some 4,000,000 bbl. more than in the previous year. Exports of crude and refined products were approximately 22,000,000 bbl., or 2,000,000 bbl. less than in 1934. Exclusive of ships bunkers, domestic consumption increased about 900,000 bbl. during the year, reaching an estimated total of 14,500,000 barrels. Only 74 wells were completed, as compared to 148 in 1934 and 91 in 1933. In proven areas 58 completions resulted in 33 producers and 25 failures. In northeastern Mexico, near the United States border, six wildcat wells were completed, all of which gave little or no encouraging results, except Rancheria No. 3, near Camargo, which is a fair-sized gas well. Four wildcats were drilled just northeast of the Northern fields (heavy-oil district), all of which were failures. A deep test was completed a short distance southeast of the Golden Lane (South fields) in Palo Blanco, which encountered small production not sufficient to exploit. On the Isthmus of Tehuantepec a wildcat well was completed for an estimated initial production of 2000 bbl. daily, a short distance south of the old Jalapa field, which was perhaps the most important new development of the year. Four other wildcats drilled in the Isthmus district resulted in failures. Fields Northern Fields (Heavy-oil District).—In the Northern fields, 18 producing wells and 20 failures were completed, as compared to 34 producers and 71 failures in 1934. The initial production of the new

Jan 1, 1936

By V. R. Garfias R. V. Whetsel

Production of crude petroleum in Mexico during 1935 totaled approximately 40,082,000 bbl., an increase of 1,925,000 bbl. over the previous year. Successful development continued in the Poza Rica field during the year, increasing production in that area from 3,708,000 bbl. in 1934 to 9,542,000 in 1935. The output of the South fields (Golden Lane) area decreased by 3,000,000 bbl. during the year, and the heavy-oil district of the Northern fields by 1,500,000 bbl. Production in the Tehuantepec fields showed a slight gain. Production of natural gasoline increased from 430,000 to 600,000 bbl. in 1935. Crude run to stills in local refineries is estimated at 30,000,000 bbl., some 4,000,000 bbl. more than in the previous year. Exports of crude and refined products were approximately 22,000,000 bbl., or 2,000,000 bbl. less than in 1934. Exclusive of ships bunkers, domestic consumption increased about 900,000 bbl. during the year, reaching an estimated total of 14,500,000 barrels. Only 74 wells were completed, as compared to 148 in 1934 and 91 in 1933. In proven areas 58 completions resulted in 33 producers and 25 failures. In northeastern Mexico, near the United States border, six wildcat wells were completed, all of which gave little or no encouraging results, except Rancheria No. 3, near Camargo, which is a fair-sized gas well. Four wildcats were drilled just northeast of the Northern fields (heavy-oil district), all of which were failures. A deep test was completed a short distance southeast of the Golden Lane (South fields) in Palo Blanco, which encountered small production not sufficient to exploit. On the Isthmus of Tehuantepec a wildcat well was completed for an estimated initial production of 2000 bbl. daily, a short distance south of the old Jalapa field, which was perhaps the most important new development of the year. Four other wildcats drilled in the Isthmus district resulted in failures. Fields Northern Fields (Heavy-oil District).—In the Northern fields, 18 producing wells and 20 failures were completed, as compared to 34 producers and 71 failures in 1934. The initial production of the new

Jan 1, 1936

By R. J. Sullivan

DURING the past twelve months the Loudon pool of the Eastern Interior Coal Basin has become established as one of the two largest discoveries since the revival of exploitation in the Illinois region and now occupies a position among the important pools of the United States. On Aug. 1, 1939, production averaged 54,000 bbl. per day from 990 wells, having accumulated a total of 10,305,000 bbl. Its very active develop-ment promises to continue for fully another year. It is the site of one of the industry's most singular large-scale gas-injection programs. LOCATION AND RESERVOIR CHARACTERISTICS At present the pool embraces an area 15 miles long by 3 ½ miles wide in eastern Fayette County, along the western rim of the now well-known Illinois Basin's deeper part, through townships 6, 7 and 8 north and ranges 2 and 3 east of the Third Meridian. It is the northernmost, and most prominent, productive structure of a group extending over a 50-mile trend southward to the Dix pool of Jefferson County. Three horizons have been proved to carry production-namely, the Weiler sandstone at 1390 ft., the Paint Creek sand at 1460 ft. and the Benoist or Bethel, at 1500 ft. Geologically, they fall in the Chester series of the upper Mississippian system, where much of Illinois' early-day oil was found, having been laid down in shallow off-shore waters as a part of the vast delta deposit underlying central Illinois and parts of Indiana and Kentucky. As a result of this type of sedimentation, followed by repeated uplifts and warping along an anticlinal axis, differ-ential deposition of sands and shales contributing to great irregularity took place. This is further reflected by wide variations in permeability, porosity and thickness of all the sands and, accordingly, in the producing characteristics of wells. Permeabilities range as high as 550 millidarcies, with the average commonly lying between 60 and 100. For the three pay horizons the mean porosity is 18 per cent, at a calculated water saturation of roughly 30 per cent. The Weiler sand has an average thickness of 25 ft., the Benoist of about 23 ft. and the Paint Creek of approximately 18 ft. Of these three productive formations the Benoist

Jan 1, 1940

By M. Duclos, A. Sawatzky

A simple model has been developed which describes the steady-state solute distribution in Ti-H type systems above the eutectoid temperature in the presence of a temperature gradient. The solute distribution is dependent on the shape of the phase boundaries. An interesting result, and one that is not observed at steady state in thermal diffusion below the eutectoid temperature, is the existence of a two-phase region. The heat of transport for hydrogen in a titanium, Q*a, over the temperature range 275" to 650.C is determined to be 4500 * 230 cal per mole. The heat of transport for hydrogen in B titanium, QB* over the temperature range 320" to 590.C is found to be 630 ± 200 cal per mole. It is also shown that thermal diffusion provides a method by which phase bounduries above the eutectoid may be determined in Ti-H type systems. IN modern technology materials are being used at constantly increasing temperatures under greater temperature gradients. Thus atomic migration in metal alloys due to a temperature gradient (thermal diffusion) may in some cases occur to an observable extent. The thermal diffusion of hydrogen in zirconium has in recent years received considerable attention1-' because of the use of zirconium alloys in nuclear power reactors. The thermal diffusion kinetics below the eutectoid (547°C) are fairly well understood. At steady state the solid solution, a, and hydride, 6, phases are completely separated with the hydride precipitating at the lower temperatures. No experimental work has been carried out in the a + B region although Droege4 suggested that a complete separation of the two phases, as observed at temperatures below the eutectoid, might not always occur. In the present investigation a simple model has been used to determine the steady-state solute distribution under a temperature gradient in Zr-H type systems heated above the eutectoid temperature. The solute distribution is shown to be dependent on the shape of the phase boundaries in the constitutional diagrams and several typical cases are discussed. The model has been applied to Ti-H. This system was chosen in preference to Zr-H because of its much lower eutectoid temperature (-300°C as compared with 547.C), thereby reducing experimental errors due to oxidation and hydriding. The heats of transport for hydrogen in the a and B phases of titanium also have been determined since they were required to compare the proposed thermal diffusion model with experiment. THEORY In the presence of a temperature gradient the atomic flux in a single-phase region of a two-com-ponent system of which the atoms of only one component are diffusing is given by:' J = - U\dx + RT3 dx) which can be written as: j-D(dn/dt +Q*n/RT2)dt/dx [11 J - -D\dT + RT2)dx [1] where D = diffusion coefficient, n = solute concentration, T = absolute temperature, R = gas constant, dT/dx = temperature gradient, and Q* = heat of transport. At steady state (J = 0) Eq. [I] leads to the solute distribution: n = noexp Q*/RT where no = a constant depending on total solute content. The heat of transport Q* can be experimentally determined from the steady-state distribution. In the present paper we shall determine the solute distribution in systems having the constitutional diagram exemplified by Ti-H shown in Fig. l.' As shown, N,(T) and NB(T) are the equilibrium solute concentrations in the a and 0 phases at temperature T. Lines AA' and CC' define the region of interest to us. The following assumptions are made: 1) Steady-state conditions prevail. 2) In a single-phase region all points on an isotherm have the same thermodynamic potential so that the composition over an isotherm is uniform. If a two-phase region exists, thermodynamic equilibrium is found only at phase interfaces. However, we assume the component of the concentration gradient along an isotherm to be small so that the composition in each phase is approximately the same as at the interface and is given by the constitutional diagram, Fig. 1. 3) There is appreciable diffusion of only one component. 4) We shall consider only the case where Qa*, QB*, and Qg*, the heats of transport for solute diffusion in the a, B, and 6 phases, respectively, are positive. This has been observed for the thermal diffusion of hydrogen in zirconium3 and titanium.10 We will show that the steady-state solute distribution above the eutectoid is primarily determined by the heats of transport and the temperature dependence of Na(T) and Np(T). It may be quite different from the steady-state distribution below the eutectoid. For example, we will see that, under certain conditions,

Jan 1, 1970

By R. E. Reed-Hill, J. L. Martin

Kinking is an important deformation phenomenon in poly crystalline a zirconium. The crjlstallo-gvaphic features of the most important form of kinking have been determined with the aid of twins formed at 77°K in grains previously kinked at high temperatures. It has been .found that the kink-band boundaries correspond to walls of edge dislocations with (1150) Burgers vectors and dislocation lines parallel to (1070). The present observations imply that basal slip is an important secondary-slip mode in polycrystalline zirconium. Previous single-crystal studies13 did not veveal this mode Other evidelzc.e for (0002)(1120) slip is also presented. ThE first studies of kinking in hexagonal metals were made by orowan,1 using single-crystal cadmium wires. He suggested that this was a new de- formation mode in metals, different from ordinary glide or twinning. Next, Hess and Barrett2 studied zinc-crystal rods in compression, and were able to offer an explanation of the phenomenon described by Orowan. They concluded that kinks required no new deformation mechanism and were a special form of deformation band that developed gradually and solely from basal glide. Similar kink bands were then observed by Washburn and parker3 on zinc crystals deformed in tension at low stresses and high temperatures. In titaniun,4 kink bands associated with {1010}<1120> prism slip have been observed in coarse-grained specimens. Magnesium5 and rhenium6 have also been observed to kink in conjunction with their basal- and {1010} prism-slip systems, respectively. Yttrium has (1010) as a predominant slip plane, but no observations of kink bands were reported.7 Since no previous investigations of kink bands in zirconium have apparently been made, this study was proposed. Its aim was to determine the crys-tallographic features of a type of kink band frequently observed in polycrystalline zirconium. EXPERIMENTAL APPARATUS All tests were performed on a type TTC Instron machine. The cross-head speed usually chosen in tension or compression was 0.02 in. per min. Ten-

Jan 1, 1964

By Joseph Gurland

EVERAL carbide-cobalt compositions were pre-^-5 pared for the purpose of determining the transverse rupture strength of various carbide-binder systems. The binder content was held at 10 and 37 volume pct Co, so as to be representative of low and high bjnder compositions. The carbides used, WC, Tic, TaC, CbC, VC and ZrC, were selected on the basis of availability, knowledge of their properties, and small solid solubilities in the binder metal at room temperature. The methods of preparation and carbon analysis of the carbides are summarized in Table I. The carbides with cobalt added were ball milled, pressed, and sintered. vacuum sintering was used throughout, except for the WC-Cs alloys, which were sintered in hydrogen. The sintering temperatures ranged from 2500" to 2750°F for the low binder alloys and from 2300" to 2550°F for the high binder alloys. Compositions and properties of the sintered com- pacts are presented in Table 11. For the transverse rupture strength, the average and range of the five best samples of each alloy are listed. Discrepancies between the actual and theoretical densities are attributed to carbon deficiencies in some samples. The theoretical densities were calculated by assuming mixtures of carbides of stoichiometric compositions and cobalt. Representative microstructures are shown in Figs. 1 to 6. The porosity was A-2 or better&apos; in all alloys except those with ZrC. A grain size of about 3 p was

Jan 1, 1958

By R. F. Slack, J. C. Draper, J. A. Younkins

In 1959, the Duquesne Light Co. was faced with the problem of moving more than 40 million tons of bituminous coal in Greene County, Pa. The coal had to travel a distance of about 4 ½ miles from a new mine portal in Rocky Run Valley to the company preparation plant and loading facilities on the Monongahela River. After careful study of this immense transport problem, Duquesne decided that the belt conveyor system described in the following pages offered the best solution. This system, now in operation, is probably one of the four or five longest permanent overland conveyor systems in existence. The general layout of the entire system is shown in Fig. I. A detailed description of the salient features of the system is presented below. THE MINE The valley of Rocky Run where the system begins is very, very narrow and very steep. It was chosen as the site of Duquesne&apos;s new mine portal because it was the only place on this particular property where the Sewickley coal seam cropped out. The valley also had two other advantages. First, it fronted on a state road and, second, it offered a site where some 4 million gallons of water could be stored for use in dust-allaying sprays needed in the mine. The company elected to construct a drift mine in the valley because this would require neither the hoisting time of a shaft mine nor the walking time of a slope mine. As part of the mine construction project, the valley was leveled by relocating its stream and filling its center with material cut from each side.

Jan 11, 1966

Bethlehem Steel Co. has just brought an all-new iron ore mine into production at Marmora, Canada, about 120 miles east of Toronto. High grade pellets produced at the mine from open-pit magnetite ore travel 64 miles by rail to the port at Picton, then go by Lake boat to help supply Bethlehem&apos;s Lackawanna, N. Y., plant. At full production about half a million tons of pellets a year will be shipped, and mining will be at a scale of more than a million tons per year of ore. Aeromagnetic surveys carried out in 1949 by the Ontario Dept. of Mines and the Canadian Geological Survey revealed an anomaly that interested Bethlehem geologists. By 1951 the company had put down some 40 diamond drillholes ranging from 460 to 1800 ft to block out the magnetite replacement deposit which lies in pre-Cambrian limestone below about 130 ft of Paleozoic limestone. The orebody, roughly 2100 ft long and up to 400 ft wide, averages about 37 pct iron, too low for direct shipment. Not only construction of concentrating and pelletizing facilities, but 20 million tons of stripping lay ahead before production could start

Jul 1, 1955

By E. C. Carris

THE particular field of application of machines utilizing air cur¬rents as the primary separating medium is in the cleaning of the fine sizes of bituminous coal. Approximately 12,000,000 tons of bituminous coal were cleaned by air machines during 1940. They have not found any application for cleaning anthracite. Since the development and introduction of the first successful com¬mercial pneumatic oscillating machine for cleaning bituminous coal in 1916, by the Sutton, Steele and Steele Co., Dallas, Texas, and the Ameri¬can Coal Cleaning Corporation, formerly of Welch, W. Va., four other successful pneumatic coal-cleaning machines have been developed and introduced to the American coal-mining industry: 1. Peale Davis: "Pneumo-Gravity" machine, 1924. 2. Arms "Concentrator," oscillating table, 1924. 3. Heyl and Patterson oscillating table, 199.7. 4. "Stump Air-Flow," pulsating air jig, 19391. Out of these five developments only the Sutton, Steele and Steele, or American Oscillating, and the Stump Air-Flow Jig remain on the market. They are the predominating pneumatic coal-cleaning machines in use in the United States. HISTORY OF AMERICAN TYPE SEPARATOR The first successful American machine, the CJ table (Fig. 1) was developed by the Sutton, Steele and Steele Co. The SJ table was the first standard model designed specifically for the cleaning of coal. It was installed in the original Crane Creek plant, owned and operated by the American Coal Co. at McComas, West Virginia. This plant was designed by The Roberts and Schaefer Co., Chicago, Ill., working in cooperation with the American Coal Cleaning Corpora¬tion, which had taken over the patent rights and sale of the pneumatic separators. Eight machines were installed in this plant. They were known as the type SJ. They were 60 by 84 in., the short dimension being the width of

Jan 1, 1943

By A. T. Beckwith

THE Lehigh Navigation Coal Company Inc. operates steep-pitch, relatively deep mines in the Panther Creek Valley, at the eastern end of the southern anthracite coal field. Commercially minable coal beds are the Mammoth,† Primrose, Orchard, and Buck Mountain,‡ their respective thicknesses average 50, 15, 1o and 12 ft. Sand slates immediately overlie and underlie these beds, though in some locations sandstone or conglomerate beds occur. Underground operations extend to a depth of 1200 ft. below the surface, and comprise a bulk of virgin work on the lower levels, and a small amount of remining on the upper levels. With increase in depth, ventilation has become a more important factor. DEVELOPMENT In early days slopes or drifts were driven in the outcropping coal on the hillsides. Subsequent development was by water-level tunnels, with portals above high water in Panther Creek. These tunnels have been maintained because they intercept and drain much water that enters the mined-out portion of the bed and otherwise would follow down to the deep workings. Below these tunnels, the coal was customarily developed by slopes. Muleways, which are zigzag chutes easy to travel, were also driven to connect lower openings with the water levels. When it became necessary to go still deeper, the slopes were abandoned, and vertical multicompartment shafts were sunk from the surface. Levels have been at vertical intervals of from 195 to 250 ft. Recent practice has been toward the latter spacing; splitting the total lift, however, by starting to mine from chutes extending halfway up to the level above. Chutes customarily are spaced at 50, 60 or 70-ft. centers along the gangways. At some mines, additional shafts have been sunk from the surface to the level containing the main pumping station, and these carry the discharge lines from the pumps. As the mines are ventilated by the exhausting system, both the hoisting and so-called water shafts serve as intakes. The main fan is always on the surface, and is connected with the return airways from the various levels by an air hole or a vertical shaft. For economy, when the present deepest levels were developed, main return-air shafts or air holes were not extended to the new level, but connections were made from the new level to that above by two or more holes. It is doubtful that this method will be continued, as complications in the system, increased resistance to flow, and other difficulties undoubtedly will counterbalance any economies this provision may afford.

Jan 1, 1942

By Samuel Taylor

IF I LIVE another fourteen months and am still con-nected with the coal industry, I shall then have com-pleted a half century with it. Since May, 1874, when .I first entered the bituminous workings as a miner, I think I have held almost every position connected with a mine except possibly that of mule driver, for which I was unfitted by reason of my religious upbringing. We are all agreed, at least I have not heard it contra-dicted, that there is serious over-production in the bituminous industry. This has come about in various ways and is easily explained. During the Fuel Admin-istration, I recall making an estimate of the possible output of the bituminous mines of the country provided they were given a full force of men and a full-car supply; my estimate was a little over a billion tons a year. A few months ago, the late Francis H. Peabody, of Chicago, made a practically identical estimate. If, however, both of these conditions should happen con-currently, there would very soon be no market for the coal, and many of the mines would close down. Even today, if 10 per cent. more cars were furnished, to the bituminous mines, market prices would drop very seriously.

Jan 4, 1923

By Michael Perch, Charles C. Russell

Nearly 7 5 per cent of the total coke production in the United States in 1940 was consumed in blast furnaces. In 1939 the percentage was 69.9, and in 1938 it was 61.3. To produce a net ton of pig iron 1757 lb. of coke was required in 1940 and 1760 lb. in 1939. These figures indicate how dependent the production of pig iron is upon the production of coke. The rate of iron production is in some measure influenced by the physical and chemical characteristics of the coke. Blast-furnace operators believe that the physical properties of coke profoundly influence the operation of the furnace. Although it is true that coke of a wide variety of physical properties is used in American blast furnaces, the periodic fluctuation of these properties is one of the causes of irregularity of blast-furnace operation. The purpose of this paper is to present a broad picture of the physical properties of by-product coke that are generally considered to be important by coke-oven and blast-furnace operators. Effects of the kind of coal used, the preparation of the coal, the rate of coking, and other factors will be considered. Of all these variables, the kind of coal used is by far the most important. In this discussion use will be made of the method of coal classification by rank1 standardized by the American Society for Testing Materials. Although this method of classification has been an American standard for several years, it has not been given the attention it deserves, especially in connection with the selection of coal for production of coke. Despite the fact that many producers of blast-furnace coke are limited to some particular source or sources of coal, a good understanding of the principles involved in setting up the standard method of classification may lead to a better appreciation of the causes of changes in coke characteristics. Furthermore, where it is necessary to select new coals as a substitute for the original supply, this method of classification can be of great assistance. The data presented have been gathered from many sources, but no attempt has been made to cover the vast literature. Instead, some of the more important data have been selected to show how coals and their carbonization affect some of the physical properties of coke. It must be emphasized that generalizations concerning the behavior of coking coals are presented and that individual coals may vary widely from the specific behavior depicted. Nevertheless, it is believed that the data illustrate certain typical behaviors. Neither was it possible to cover completely all the factors involved; for example, the macroscopic constituents of coal are believed to have important effects on the physical properties of coke, but since there is little information available for such study, and since vitrain, clarain, and durain are neither

Jan 1, 1943

By Michael Perch, Charles C. Russell

Nearly 7 5 per cent of the total coke production in the United States in 1940 was consumed in blast furnaces. In 1939 the percentage was 69.9, and in 1938 it was 61.3. To produce a net ton of pig iron 1757 lb. of coke was required in 1940 and 1760 lb. in 1939. These figures indicate how dependent the production of pig iron is upon the production of coke. The rate of iron production is in some measure influenced by the physical and chemical characteristics of the coke. Blast-furnace operators believe that the physical properties of coke profoundly influence the operation of the furnace. Although it is true that coke of a wide variety of physical properties is used in American blast furnaces, the periodic fluctuation of these properties is one of the causes of irregularity of blast-furnace operation. The purpose of this paper is to present a broad picture of the physical properties of by-product coke that are generally considered to be important by coke-oven and blast-furnace operators. Effects of the kind of coal used, the preparation of the coal, the rate of coking, and other factors will be considered. Of all these variables, the kind of coal used is by far the most important. In this discussion use will be made of the method of coal classification by rank1 standardized by the American Society for Testing Materials. Although this method of classification has been an American standard for several years, it has not been given the attention it deserves, especially in connection with the selection of coal for production of coke. Despite the fact that many producers of blast-furnace coke are limited to some particular source or sources of coal, a good understanding of the principles involved in setting up the standard method of classification may lead to a better appreciation of the causes of changes in coke characteristics. Furthermore, where it is necessary to select new coals as a substitute for the original supply, this method of classification can be of great assistance. The data presented have been gathered from many sources, but no attempt has been made to cover the vast literature. Instead, some of the more important data have been selected to show how coals and their carbonization affect some of the physical properties of coke. It must be emphasized that generalizations concerning the behavior of coking coals are presented and that individual coals may vary widely from the specific behavior depicted. Nevertheless, it is believed that the data illustrate certain typical behaviors. Neither was it possible to cover completely all the factors involved; for example, the macroscopic constituents of coal are believed to have important effects on the physical properties of coke, but since there is little information available for such study, and since vitrain, clarain, and durain are neither

Jan 1, 1943