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By J. E. Pogue, F. G. Coqueron

This paper describes the sources of funds required by the petroleum industry to finance capital expenditures and also presents a discussion of the effect of rising construction costs on these expenditures. The petroleum industry obtains its capital funds from several sources: (I) internal, from retained cash earnings; and (2) external, from borrowings and the sale of securities to the public. The upward trend of capital expenditures of the petroleum industry is caused in the main by the influence of two powerful factors: (I) the physical growth in the demand for oils; and (2) the rising cost of drilling wells and constructing refineries, pipe lines, and other facilities. The segregation of these factors is accomplished by deflating the actual capital expenditures so that they are shown in terms of 1939 costs and then subtracting the adjusted series from the actual figures to yield a set of data representing the expenditures made on account of higher costs. Rising costs affect prices and the portion attributable to this factor had to be generated from the cash earnings of the industry, which called for higher oil prices. Introduction Capital may be defined as "wealth employed in or available for production." All production requires capital. Expanding industries require more capital than static ones, and technological industries employ more capital than. those in which little equipment is needed. The petroleum industry is both rapidly growing and highly technological, and, being a large industry, its capital requirements are prodigious, amounting to about one-seventh of the total of all American business, excluding agriculture.* Capital formation may be defined as the method by which the wealth or capital needed in the productive processes is created. There are various ways in which capital funds may be obtained but there is only one way in which capital can be created—out of production in excess of consumption, that is, savings. The physical realities are simple, but the monetary concepts are complicated because the mechanism of credit can draw upon future savings. Source of Capital Funds An industry, such as the petroleum industry, can obtain its capital funds from

Jan 1, 1949

By P. L. De Bruyn, R. J. Charles

THE transfer of kinetic energy of translation into other forms of energy by impact is a fundamental process in most crushing and grinding operations. During and after the impact process the original source energy may be accounted for in any of the following possible forms: 1) Kinetic energy of translation of both the impacted and impacting objects. 2) Kinetic energy of vibration of the components of the impact system. 3) Potential energy as strain energy of the components of the system or in the form of residual stresses. 4) Heat generated by internal friction during plastic deformation or during damping of elastic waves. 5) New surface energy of fractured materials. At any instant during the impact process only the strain energy of the components of the system can contribute directly to the brittle fracture process. If fracture is the desired result, as in comminution, it would seem advantageous to choose or arrange the conditions of impact so that a maximum amount of the original kinetic energy could be converted to strain energy at some moment during a single impact. The present work deals with determination of these desirable conditions for a simple case of impact and application of the principles involved to general cases of impact. Experimental Method: Longitudinal impact of a rod with a fixed end was chosen as the impact system for investigation. The rod was mounted horizontally and the fixed end was formed by butting one end of the rod against a rigidly mounted steel anvil. The rod, of pyrex glass, was 10 in. long by 1 in. diam with both ends rounded to a 6 in. radius. The rounded ends permitted reproducible impacts on the free end of the rod and assured a symmetrical fixed end. Pyrex was selected as the rod material because of the marked elastic properties of such glass and the similarity of fracture between pyrex and many materials encountered in crushing and grinding operations. The frequency of natural longitudinal oscillation of the rod was 10 kc, and thus simple electronic equipment could be used for observation of strain changes occurring in the rod at this frequency. As shown in Fig. 1, impacts on the free end of the rod were obtained either by a pendulum device or by a spring-loaded gun. Relatively heavy hammers (100 to 600 g) of mild steel were used in the pendu- lum impacts, while fairly light projectiles (20 to 80 g) were fired from the spring-loaded gun. One of the main objects of the experimental work was to obtain the strain-time history of the rod as a function of the mass and kinetic energy of the impacting hammers. For this purpose a technique involving wire resistance strain gages and a recording oscilloscope was employed. Five gages were applied at equidistant sections along the rod, and by means of a switching arrangement the strain-time history at any section, and for any impact, could be obtained in the form of an oscillograph with a time base. The equation relating strain and voltage change across a strain gage through which a constant current is flowing is as follows: e = ?v/iRF [1] ? = strain, ?v = voltage change, i = gage current, R = gage resistance, and F = gage factor (from manufacturer's data — SRA type, Baldwin Lima Corp.). With the above equation an oscillograph depicting voltage change vs time on a single trace can be converted directly to a strain-time diagram if a calibration of the vertical response on the oscilloscope screen for specific voltage inputs is available. In the present case the calibration was obtained by photographing precisely known audio frequency voltages on the same oscillograph as that on which a voltage-time trace from a strain gage had been made. Synchronization of the beginning of the single trace with the beginning of the impact was accomplished by permitting contact of the impacting objects to close an electrical circuit from which a voltage pulse, sufficient to initiate the trace, was obtained. The struck end of the rod was lightly silvered for purposes of electrical conduction so that it would form one of the electrical contacts. Markers every 100 micro-seconds on the traces served for a time base calibration. Determinations of the kinetic energies of translation prior to impact were made in the case of the pendulum hammers by measuring the height of fall of the hammer and in the case of the projectiles by measuring the exit velocity from the gun barrel by means of an electrical circuit employing light sources, slits, and phototubes.' During the experimental work it became evident that the time of contact between the impacting object and the rod was an important variable in the impact process. Measurements of the times of contact were made, therefore, for every impact for which a strain-time record was obtained. The time of contact was determined by permitting the impacting components, when in contact, to act as a closed switch and discharge a condenser at relatively constant voltage. The discharge was observed and photographed with a time base on the oscilloscope screen.

Jan 1, 1957

By Frank Foote

PRECISION lattice-constant measurements have been widely used in the study of cubic solid solutions but as yet have been rarely applied to noncubic solid solutions. (See, however, references I and 2.) With the high precision at present attainable in the measurement of lattice constants, the X-ray method should be readily applicable to noncubic solid solutions. In the work reported here, hexagonal close-packed magnesium was used as the solvent and either lead, bismuth or gold as the solute. In the magnesium-lead and mag-nesium-bismuth systems the a and c lattice constants were determined as a function of composition, densities were calculated from these lattice-constant data, these theoretical densities were compared with those directly measured and the solid solubility limit was determined on quenched specimens over a considerable range of temperature. In the magnesium-gold sys-tem, the solid solubility is very small but we have obtained an indirect check on the solubility limit previously reported.

Jan 1, 1940

By David Firewick, Daniel Stewart, Richard Rein

Panel caving of the Henderson orebody began in August, 1976. Fifty months later, on September 10, 1980, the cave zone appeared on surface as a steep-walled cavity positioned directly above the initial cave area. Although surface survey data revealed the development of a slight depression over the production area, surface inspection by geologists, three days prior to breach- ing, resulted in no evidence of impending glory-hole development. Geologic factors such as rock contacts and alteration-zone boundaries had little influence on the location of the initial glory hole. Since initial breakthrough, the glory-hole shape and growth have not directionally followed caveline advance because of topography and faulting. Based on periodic data, mine production has resulted in immediate growth of the Henderson glory hole.

Jan 1, 1984

The Gooseberry Mine is located 38 krn (24 miles) by road east of Reno, 13 km (8 miles) south of Interstate 80. The mine was originally discovered in 1906 and remained in the control of the Martin family of Fresno, who worked the-property with Mexican ranch hands for 68 years. Westcoast took over the property in 1976 from Apco Oil Corporation. During the time the Martins operated the mine, a 305 m (1,000 ft) inclined shaft was sunk with drifts developed on eight levels exceeding a total of 3,000 m (9,000 ft) in length. It is interesting to note that for over one -half century all development ore was stockpiled. West- coast, the United States mining subsidiary of Home Oil Company Ltd., Calgary, Alberta, completed sinking another vertical shaft to the 396 m (1,300 ft) level. Development work between 122 m and 305 m (400 ft and 1,000 ft) levels has proved the existence of a fine ore body over 300 m (1,000 ft) long. The silver-gold ore grade is fairly consistent in the vertical section, but copper, lead and zinc may show slight increases with depth. Average width of the ore bearing portion of the vein is 2.5 m (8.3 ft). Stoping is by cut-and-fill method. Average silver values within the ore zone have increased from the 152 m (500 ft) level to the 305 m (1,000 ft) level, although the gold values do show some decrease. It is not possible for the geological staff to predict the depth of the ore. However, several years of ore reserves have been proved in the existing mining areas. Important ore minerals are argentite, native gold, and electrum. Trace amounts of galena, chalcopyrite, and sphalerite are associated with the precious metal mineralization. The vein is mainly composed of calcite and quartz. Mine-run underground ore is dumped from the hoisting skip into a coarse ore bin followed by a jaw crusher, an impact crusher, and a 600 mt (650 st) fine ore bin. The mill has a capacity of 317 mt per day (350 st per day). Two-stage grinding is done by a rod mill followed by cyclones with the underflow sent to a ball mill in closed circuit with the cyclones. Cyclone overflow after conditioning receives a primary float in four 1.7 cu m (30 cu ft) cells and a second stage of conditioning ahead of 24 0.8 cu m (30 cu ft) secondary flotation cells. No cleaning stages are used. Flotation tailings are cycloned for a sand-slime separation with the sands used as underground stope fill and the slime portion to tailing dam storage.

Jan 1, 1981

By C. H. White

Discussion of a Paper by Mr. C. H. White, read at the Atlantic City Meeting, February, 1904. (Annual Meeting, February, 1005.) ARTHUR JARMAN, Sydney, New South Wales, Australia (communication to the Secretary*) : All designs for modern metal¬lurgical and chemical laboratories should provide each student's desk with a hood or cupboard for the removal of fumes, but I doubt the advisability of placing air-baths and similar apparatus close to the hot plate. It seems to me that unless the draft be exceptionally strong the fumes from ordinary wet assay work will corrode the iron-work of the fittings, in which case the baths would have to be removed to a general desk in order to lighten the work of the laboratory attendant. Since the laboratory described by Mr. White has been in use for two years, I should like to ask if any inconvenience has resulted from this corrosion. If not, it is certainly an important improvement to have the air-baths and similar apparatus placed -on the student's desk. The hoods described by Mr. White are supplied with a good draft by means of a fan, which gives them a great advantage over those at the metallurgical laboratory at the University, Sydney, in that no doors to the hood are needed. Each hood in the laboratory at Sydney is connected by a glazed earthenware drain-pipe with a vertical flue, 20 ft. high, having a lighted gas jet at the bottom to assist the draft. Although the draft is good, fumes of sulphuric acid cannot be drawn o$ unless the doors of the hood are lowered more than half-way. In my opinion, a fan should be used for the purpose of creating the draft, and glazed drain-tile should invariably be used for the flues because no other material possesses the same advantages. I know of a recent instance in which a laboratory containing

Mar 1, 1905

For the year ending February, 1923 PRESIDENT ARTHUR S. DWIGHT, District 0 NEW YORK, N. Y. PAST PRESIDENTS HERBERT HOOVER, District 4 WASHINGTON, D. C. EDWIN LUDLOW, District 0 NEW YORK, N. Y. FIRST VICE-PRESIDENT J. V. W. REYNDERS NEW YORK, N. Y. TREASURER CHARLES F. RAND NEW YORK, N. Y. SECRETARY FREDERICK F. SHARPLESS,. . . . . NEW YORK, N. Y. ASSISTANT SECRETARY PERCY E. BARBOUR NEW YORK, N. Y.

Jan 7, 1922

By Ralph Hultgren

Few phase diagrams of alloys composed of two transition metals have been adequately studied, probably because of the high melting points involved. Transition metals are the elements that have inner shells incompletely filled with electrons. They comprise groups lIIa to VIIIa of the periodic table, including more than half of all metals. We have chosen to study two systems whose comparatively low melting points allowed the alloys to be melted in a molybdenum resistance furnace. The nickel-palladium system proved to consist of a simple series of solid solutions, but iron-palladium manifested several remarkable features. The main characteristics of the latter diagram were decisively established, but lack of time prevented precise determination of phase boundaries. The gamma to alpha transformation in this system is unusual and warrants further study. Grigorjewl determined the liquidus and solidus of the iron-palladium system by thermal methods. He found a minimum melting point, but no eutectic. He also found that palladium lowered the gamma to alpha and raised the gamma to delta transformation temperatures of iron, with a complete series of solid solutions existing between gamma iron and palladium. His measurements also indicated a compound or quptbr-lattice near the composition FePda. Jellinghausz found that annealing at 500" C. greatly increased 111 magnetic coercive force of an alloy of composition FePd. X-ray diffraction photographs showed that a tetragonal ordered phase had formed during the anneal. Hocart and Fallot made magnetic measurements over the entire range of composition. They found that less than 5 atomic per cent Pd

Jan 1, 1939

By Ralph Hultgren

Few phase diagrams of alloys composed of two transition metals have been adequately studied, probably because of the high melting points involved. Transition metals are the elements that have inner shells incompletely filled with electrons. They comprise groups lIIa to VIIIa of the periodic table, including more than half of all metals. We have chosen to study two systems whose comparatively low melting points allowed the alloys to be melted in a molybdenum resistance furnace. The nickel-palladium system proved to consist of a simple series of solid solutions, but iron-palladium manifested several remarkable features. The main characteristics of the latter diagram were decisively established, but lack of time prevented precise determination of phase boundaries. The gamma to alpha transformation in this system is unusual and warrants further study. Grigorjewl determined the liquidus and solidus of the iron-palladium system by thermal methods. He found a minimum melting point, but no eutectic. He also found that palladium lowered the gamma to alpha and raised the gamma to delta transformation temperatures of iron, with a complete series of solid solutions existing between gamma iron and palladium. His measurements also indicated a compound or quptbr-lattice near the composition FePda. Jellinghausz found that annealing at 500" C. greatly increased 111 magnetic coercive force of an alloy of composition FePd. X-ray diffraction photographs showed that a tetragonal ordered phase had formed during the anneal. Hocart and Fallot made magnetic measurements over the entire range of composition. They found that less than 5 atomic per cent Pd

Jan 1, 1939

Consolidated Gold Fields Limited published annually an excellent reference, GOLD 1978, GOLD 1979, giving the Supply and Demand for Gold, Recent Developments and Prospects, Soviet Gold Production, etc. This outstanding reference is authored by Christopher Glynn, Investment Department, London, Great Britain. The 1978 Report marked the tenth anniversary of Gold Field's review of world gold market developments; and from it and the 1979 report, the following information was derived. The recovery of gold is widespread in the Soviet Union. Originally, gold was mined principally in the Urals, but in the last few years several major deposits have been discovered in the southwestern areas of the Soviet Union. One of the most dramatic discoveries has been the Muruntau deposit in Western Uzbekestan. This deposit, discovered in 1958, is reported to be the largest and among the lowest cost producers in the Soviet Union. It is located in Armenia, approximately 750 km (465 miles) northeast of the Iran-Afghanistan border, lying in the center of the Kyzylkurn (Red Sands) desert at the foot of Muruntau Mountain. Free gold occurs in both fine and coarse size in quartz veins up to 20 m (66 ft) thick associated with a small percentage of sulfides, mainly arsenopyrite. The ore zone constitutes a large gold-enriched stock work of about 4 sq krn (1.5 sq miles). The development of Muruntau was a major undertaking with open -pit development and construction of the mill and refinery complex started early in 1967, and the first gold bar poured in mid-1969. At the end of the first construction stage in 1970, the mill building was an imposing structure about 38 m (125 ft) high and 330 (1,080 ft) in length housing, probably, 11 parallel milling circuits. The first construction stage also included six 50 m (165 ft) diameter thickeners and 30 Pachuca tanks. The original mill complex was tripled in size after large additional gold reserves were discovered at a depth of 600 m (1,970 ft); and the deposit is now being exploited by both open- pit and underground workings. Ore is ground in semi-autogenous mills with the free gold being recovered into a high-grade concentrate on shaking tables. Table tailings are purnped to duplex spiral classifiers in closed circuit with the grinding mills. Classifier overflow is then thickened before being transferred to the Pachuca building where cyanidation takes place. An ion exchange resin is then added in a countercurrent

Jan 1, 1981

By E. H. Crabtree, V. W. Winters, T. G. Chapman

IN 1939 one of the authors* described advances in carbon-cyanidation for the period 1932 to 1939 • T. G. Chapman: A Cyanide Process Based on the Simultaneous Dissolution and Adsorption of Gold. Trans. AIME (1939) 134, 207. and included: (1) the dissolution of gold in an ore pulp by cyanide and its simultaneous adsorption by carbon, (2) the stage addition of adsorptive carbon and its movement countercurrent to the flow of the ore pulp, and (3) the recycling of adsorptive carbon. Considerable additional experimental and pilot plant work have been done by the authors since 1939 and the results of such work E. H. CRABTREE, JR., Member AIME, is Director of Milling, Eagle-Picher Mining and Smelting Co., Miami, Okla., V. W. WINTERS is Superintendent, Sahuarita Concentrator, Eagle-Picher Mining and Smelting Co., Tucson, Ariz., and T. G. CHAPMAN, Member AIME, is Dean, College of Mines, University of Arizona, Tucson. AIME Sun Francisco Meeting, February 1949. TP 2744 B. Discussion (2 copies) may be sent to Transactions AIME before March 31, 1950. Manuscript received March 3, 1949. have been sufficiently encouraging to justify a second paper. Developments from 1939 to 1948: In 1941, Verne W. Winters did the first experimental work in eliminating agitation during dissolution and adsorption and thereby demonstrated that the dissolution of gold by cyanide and its simultaneous adsorption by carbon take place essentially to completion in a stagnant pulp. Shortly thereafter, and as a result of the stagnant pulp experimental work, Winters and Chapman demonstrated that soluble gold, in a cyanide ore pulp, would migrate from the ore pulp through a perforated container and be adsorbed by carbon within the container. During the same year, the Eagle-Picher Mining and Smelting Co. erected a 25-ton capacity pilot plant at the Harquahala mine about 9 miles from Salome, Ariz. Experimental work at this plant comprised chiefly the stagnant pulp modification of carbon-cyanidation although considerable work was done in the grinding and activation of carbon, and testing various methods of extracting adsorbed gold from carbon. Soon after the completion of the Harquahala

Jan 1, 1951

By E. H. Crabtree, T. G. Chapman, V. W. Winters

IN 1939 one of the authors* described advances in carbon-cyanidation for the period 1932 to 1939 • T. G. Chapman: A Cyanide Process Based on the Simultaneous Dissolution and Adsorption of Gold. Trans. AIME (1939) 134, 207. and included: (1) the dissolution of gold in an ore pulp by cyanide and its simultaneous adsorption by carbon, (2) the stage addition of adsorptive carbon and its movement countercurrent to the flow of the ore pulp, and (3) the recycling of adsorptive carbon. Considerable additional experimental and pilot plant work have been done by the authors since 1939 and the results of such work E. H. CRABTREE, JR., Member AIME, is Director of Milling, Eagle-Picher Mining and Smelting Co., Miami, Okla., V. W. WINTERS is Superintendent, Sahuarita Concentrator, Eagle-Picher Mining and Smelting Co., Tucson, Ariz., and T. G. CHAPMAN, Member AIME, is Dean, College of Mines, University of Arizona, Tucson. AIME Sun Francisco Meeting, February 1949. TP 2744 B. Discussion (2 copies) may be sent to Transactions AIME before March 31, 1950. Manuscript received March 3, 1949. have been sufficiently encouraging to justify a second paper. Developments from 1939 to 1948: In 1941, Verne W. Winters did the first experimental work in eliminating agitation during dissolution and adsorption and thereby demonstrated that the dissolution of gold by cyanide and its simultaneous adsorption by carbon take place essentially to completion in a stagnant pulp. Shortly thereafter, and as a result of the stagnant pulp experimental work, Winters and Chapman demonstrated that soluble gold, in a cyanide ore pulp, would migrate from the ore pulp through a perforated container and be adsorbed by carbon within the container. During the same year, the Eagle-Picher Mining and Smelting Co. erected a 25-ton capacity pilot plant at the Harquahala mine about 9 miles from Salome, Ariz. Experimental work at this plant comprised chiefly the stagnant pulp modification of carbon-cyanidation although considerable work was done in the grinding and activation of carbon, and testing various methods of extracting adsorbed gold from carbon. Soon after the completion of the Harquahala

Jan 1, 1951

By S. Usui, I. Iwasaki

The effect of pH on the adsorption of dodecylamine at the mercury-aqueous solution interface was investigated by differential capacity and electrocapillary measurements. With dodecylammonium acetate, the differential capacity curves showed two desorption peaks in the cathodic branch with their relative intensities varying with the solution pH. With dodecyltrimethylammonium chloride, only one cathodic de-sorption peak was observed in the same pH range. Through thermodynamic analysis of the electrocapillary curves, the adsorption density of undissociated amine was evaluated separately from that of aminium ion. The adsorption densities of the un-dissociated amine and of the total amine increased with increasing pH. The ratio at the interface of undissociated amine to aminium ion was several orders of magnitude greater than the ratio in the solution and increased with increasing pH. The potential at the closest distance of approach of counter ions to the mercury surface was compared with values of zeta potential on quartz previously reported. The most important variable in the flotation separation of minerals is probably the pH of the pulp, and a number of theories have been proposed to explain its effect on the condition of the mineral surfaces, on the dissociation of collectors and of inorganic and organic species (accidentally present or intentionally added) in the pulp, and on the mineral-collector interaction. In the development of a theoretical background for oxide flotation systems, an experimental approach based on electrokinetic measurements has been of much value, although the effect of pH becomes confounded since it governs both the electrochemical conditions of the oxide surface and the dissociation of the collector. For investigation of the adsorption behavior of long-chain collectors on oxide minerals, however, electrokinetic potential measurements are the most widely used technique. Hydrogen and hydroxyl ions are found to be the potential determining species, thereby governing the interfacial electrical conditions. The electrostatic interaction between the charged mineral surfaces and ionized collectors is regarded as the driving force for the adsorption of the collectors. An association of alkylamine collectors adsorbed on quartz surfaces has been postulated from streaming potential measurements, and a term "hemi-micelles" has been proposed.' The possibilities of coad-sorption of undissociated amine along with aminium ion has been inferred from contact angle measurements? and from adsorption studies.~ Electrochemical titration as applied to silver sulfide provides a more quantitative approach to the analysis of the electrical double layer at an ionic solid-solution interfaceqG and the electrochemical evidence for the adsorption of amine at pH 4.7 indicates a specific affinity of dodecylammonium ion towards silver sulfide surfaces, whereas at pH 9.2 the adsorbed species might be free arnine." A combination of differential capacity and electrocapillary measurements on a dropping mercury electrode was reported to be a sensitive method of provid- ing reliable information on the adsorption behavior of dodecylammonium acetate (DAA) at a natural (near neutral) pH.? It was also shown that there were striking similarities in the properties of the double layer and in the adsorption behavior of the amine on mercury and on such ionic solids as quartz, silver sulfide, and silver iodide. The effect of pH on the differential capacity curves at a mercury-sodium fluoride solution interface has been investigated by Austin and Parsonss who reported that between pH 7 and pH 11 there was very little effect. In the present paper, the adsorption behavior of DAA was investigated as a function of pH through differential capacity and electrocapillary measurements and the information gathered was correlated with that available in literature on quartz and silver sulfide. Experimental The apparatus and the method used for determining the differential capacity and the electrocapillary curves were identical to those described previously.' The ionic strength of the supporting electrolyte was fixed at 0.1 M with potassium fluoride, and the pH of the solution with potassium hydroxide. Only the neutral to alkaline range was covered in order to avoid the dissolution of the glass vessel with hydrofluoric acid. Results In Fig. 1 the differential capacity has been plotted against the applied potential at a DAA concentration of 10-' M at three different pH values. The curves are characterized by one capacity peak in the anodic branch, by two capacity peaks in the cathodic branch, and by a marked depression in capacity between the peaks. The depression indicates an adsorption of the arnine in this potential range. One of the cathodic peaks appears at pH 7.3 near -1.4 v and decreases with increasing pH. The other appears at pH 8.9 near —1.2 v and increases with increasing pH. At pH 9.6 only the latter peak is observed. Beyond the cathodic peaks, all the curves tend to converge with the curve in the absence of DAA, implying that two different species are being desorbed in this potential region. The anodic peak near 0.0 v increases markedly with increasing pH. The well-defined anodic peaks at pH 8.9 and 9.6 were accompanied by an appreciable increase in the current flow (in excess of O.luA), and, therefore, is a "pseudo-capacity"'" due to a

Jan 1, 1971

By N. M. Parikh, T. J. Koppenaal

The strengthening mechanism of fiber-reinforced silver has been investigated as a function of fiber density and fiber material. Stress-strain curves were determined in the range 2 x 10-6 to 2 x 10-3 plastic styain and slip lines were examined. The yield strength at 0.2 pct permanent strain is markedly dependent upon fiber density but the stress necessary to initiate plastic deformation is independent of fiber density. The strengthening mechanism of the fibers is shown to be malogous to grain boundary strengthening in poly crystalline metals. The variation in strengthening with different types of fibers is also noted and discussed. In recent years, considerable progress has been made in the understanding of the mechanical properties of two-phase systems, particularly in the classical dispersed-phase alloys where the separation between the dispersed phases is 0.01-0.1µ. However, little work has been done on fiber-reinforced metals where the dispersed-phase separation is considerably larger than this. Parikh1 investigated the mechanical properties of many fiber-reinforced metals and found that two general relationships are always observed, as follows: 1) A fibrous network incorporated into a second weaker metal strengthens the latter, and the amount of strengthening increases with fiber concentration. 2) At a corrstant fiber concentration, the amount of strengthening in a given matrix can vary considerably, depending upon the type of fiber employed. The object of the present investigation was to examine the fuiidamental factors controlling these two observations. procedure: Fig. 1 shows the initial step in the fabrication of the specimens. The sieve is shaken so that the fibers fall into a mold with the longitudinal axes of most fibers in the X-Z plane. The fibers are then compressed to a predetermined density, thus forming a "felt", and the necessary amount of matrix metal is added to the top of the felt. The mold is heated, in vacuum or hydrogen, to above the melting point of the matrix metal; the molten metal flows into the felt, and the entire assembly is cooled. This produces a "composite" that is essentially free of voids. A number of composites were prepared in this manner using 1/4-in. kinked lengths of mild steel

Jan 1, 1962

By Elton A. Youngberg

The Holden mine operated by the Chelan Division of the Howe Sound Co. is on the east slope of the Cascade Range in north central Washington on the south slope of Railroad Creek valley at an elevation of 3500 ft. The mine may be reached by a 40 mile boat trip from the town of Chelan which is at the southern tip of Lake Chelan, to Lucerne at the mouth of Railroad Creek and an 11. mile bus ride up Railroad Creek to Holden. A11 freight and concentrate is moved over this route to Chelan Falls on the Columbia River which is on the railroad four miles below the town of Chelan. The mine is now producing 2000 tons of gold, copper, and zinc ore per day which is treated in the Holden mill. Gold-copper and zinc concentrates are made, the first of which is shipped to Tacoma, Wash., and the latter to Kellogg, Idaho, for smelting. Ore is broken by long-hole blasting using the Noranda system which has been modified to meet local conditions. Until recently, blastholes have been drilled by diamond drills. Now a partial substitution of percussion drill holes, drilled with tungsten carbide insert bits, is being made. Geology The ore body occurs as a replacement deposit in a highly metamorphosed series of sedimentary rocks, mainly gneiss and schists, in a shear zone several hundred feet in width and of undetermined length. Commercial ore has been found in mineable widths of 25 to 100 ft for approximately 2500 ft along its strike. The commercial minerals are chalcopyrite, sphalerite, and gold. During the period of mineralization considerable silicifica-tion took place giving the ore an abrasive drilling characteristic. Following the period of mineralization, numerous dikes were introduced into the ore body. The earlier ones were of granite composition having a width of a few inches up to 80 ft. These were followed by much younger, fine grained basic dikes which usually do not exceed 2 ft in width. Development of Percussion Blasthole Drilling Equipment Test work with the 1½-in. tungsten carbide bit was carried on in development headings for several months early in 1947. The short life of the bits, because of gauge loss caused by the abrasive nature of the rock, prevented its adoption for this use. However fast drilling speed and ability to drill a long uniform hole suggested its use for drilling blastholes in competition with diamond drills as diamond costs were steadily increasing and exper-ienced drillers were difficult to obtain. The 1½-in. bit was the largest available at the time initial test work was started with sectional steel. The 1½-in. hole limited the diameter of the steel thread and coupling which could be used. Type F couplings were first used but because of the small thread section excessive breakage of the steel was experienced. Type H couplings were tried next. In order to use this coupling which is 15/8 in. in outside diameter, it was reduced to 1 3/8 in. giving 1/8 in. clearance between the coupling and the hole. Rod breakage at the thread was substantially reduced but some coupling breakage was experienced, however the overall performance was considered satisfactory (see Fig 1 for illustration of coupling and thread). Early test work with the 1½ in. bit indicated machines of piston diameters larger than 255 in. would cause inserts to loosen or break. It was found however that the additional weight of the sectional steel cushioned the blow enough to prevent bit failures when 3-in. Leyners were used. Rods used with the 1½-in. bits were 7/8 in. q. o. for sectional steel and 1 in. q. o. for all chuck pieces. In May 1948, 2-in. tungsten carbide bits became available and test work was immediately started. The 2-in. hole approximated the AX (1 15/16 in.) diamond drill hole which was being used exclusively for blastholes and permitted their substitution for diamond drill holes in a ring without alteration of pattern, burden, or explosives. The 2-in. bit also gave room in the hole for larger couplings and permitted the use of heavier rods and 3½-in. machines, increasing the

Jan 1, 1950

By G. B. Misra

Though resistance to flow offered by mine airways supported with timber sets has been an object of study over the last half century, no accurate relation has yet been established from which prediction of the resistance coefficient of a projected timbered airway can be made. Zenofontowa et al. developed an empirical relation, but this relation has not been found to satisfactorily correlate experimental data obtained by Sales and Hinsley. This led the author to develop a set of simple theoretical relations between the resistance coefficient of timbered airways and the various parameters affecting it, such as the type and spacing of sets as well as the shape and size of members forming the set. Experiments were designed with the help of a laboratory model airway to verify the validity of the relations developed. With the experiments conducted so far with 4, 3 and 1-piece sets of 3.4 x 3.4, 2..5 x 2.5, and 4.5 X 4.5-cm square-section timbers in a 45.8 x 38-cm model airway, the theoretical relations have been shown to hold.

Jan 1, 1972

Jan 5, 1976

By Enid C. Plante

THIS paper deals with the flotation of the mineral fluorite (calcium fluoride) and of two associated gangue minerals, calcite and quartz. The aim of the investigation was to produce "acid-grade" fluorite, which must contain less than one per cent of silica. Several reagents are used successfully in practice for floating fluorite from its ores. Oleic acid is the most widely used collector, usually at temperatures above 60°C, with sodium silicate as a dispersant for quartz and quebracho or tannin to depress calcite. Sulphides (e.g., galena) are often removed first by xanthate flotation. Many investigators23 report results in which more than 80 pct of the fluorite is recovered in a concentrate assaying 96 pct or more of fluorite and less than I pct of silica. This investigation was undertaken with the intention of floating the gangue, which is the minor constituent of the ore, from the fluorite. Hence emphasis was first placed on the cationic compounds that float quartz. No satisfactory separations were obtained in this way, and other reagents were investigated to discover whether these were more effective than oleic acid in floating fluorite from quartz in the usual way. The first part of the paper describes experiments with several long-chain collectors available commercially. Most of this work has been by captive-bubble and cylinder flotation tests, with some batch tests in a flotation machine. The second part describes the use of sodium cetyl sulphate as a collector for fluorite and includes laboratory tests and extension of the work to batch tests in the flotation machine. A method for determining the adsorption of sodium cetyl sulphate on fluorite has been developed and is described. Theory of Collection by Paraffin-chain Salts It may be assumed that these compounds are adsorbed at the mineral surface in one or more of three ways outlined by Kolthoff :12 I. Exchange adsorption between lattice ions in the mineral surface and collector ions in solution. Closely related is adsorption by the collecting mechanism postulated by Taggart,17 in which there is metathesis between the collector and the mineral cation or anion. 2. Exchange adsorption between adsorbed gegen ions (p. 67, ref. 19) and collector ions in solution. 3. Adsorption of nonelectrolytes (polarnonpolar) without displacement of adsorbed ions. With cationic collectors, inorganic cations in the solution (e.g., hydrogen ion) compete with the collector ions and therefore act as depressants, while inorganic anions have the same effect with anionic collectors. From this follows the general conclusion that ions of the same charge as

Jan 1, 1947

By Enid C. Plante

This paper deals with the flotation of the mineral fluorite (calcium fluoride) and of two associated gangue minerals, calcite and quartz. The aim of the investigation was to produce "acid-grade" fluorite, which must contain less than one per cent of silica. Several reagents are used successfully in practice for floating fluorite from its ores. Oleic acid is the most widely used collector, usually at temperatures above 60°C, with sodium silicate as a dispersant for quartz and quebracho or tannin to depress calcite. Sulphides (e.g., galena) are often removed first by xanthate flotation. Many investigators23 report results in which more than 80 pct of the fluorite is recovered in a concentrate assaying 96 pct or more of fluorite and less than I pct of silica. This investigation was undertaken with the intention of floating the gangue, which is the minor constituent of the ore, from the fluorite. Hence emphasis was first placed on the cationic compounds that float quartz. No satisfactory separations were obtained in this way, and other reagents were investigated to discover whether these were more effective than oleic acid in floating fluorite from quartz in the usual way. The first part of the paper describes experiments with several long-chain collectors available commercially. Most of this work has been by captive-bubble and cylinder flotation tests, with some batch tests in a flotation machine. The second part describes the use of sodium cetyl sulphate as a collector for fluorite and includes laboratory tests and extension of the work to batch tests in the flotation machine. A method for determining the adsorption of sodium cetyl sulphate on fluorite has been developed and is described. Theory of Collection by Paraffin-chain Salts It may be assumed that these compounds are adsorbed at the mineral surface in one or more of three ways outlined by Kolthoff:12 1. Exchange adsorption between lattice ions in the mineral surface and collector ions in solution. Closely related is adsorption by the collecting mechanism postulated by Taggart,17 in which there is metathesis between the collector and the mineral cation or anion. 2. Exchange .adsorption between adsorbed gegen ions (p. 67, ref. 19) and collector ions in solution. 3. Adsorption of nonelectrolytes (polar-nonpolar) without displacement of adsorbed ions. With cationic collectors, inorganic cations in the solution (e.g., hydrogen ion) compete with the collector ions and therefore act as depressants, while inorganic anions have the same effect with anionic collectors. From this follows the general conclusion that ions of the same charge as

Jan 1, 1949

Jan 1, 1959