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By R. I. Jaffee, H. R. Ogden

AT the present time, there appear to be two conflicting opinions on the solubility of boron in titanium. P. Ehrlich' has indicated from X-ray diffraction work that boron is soluble in titanium up to TiB0.8 (17.8 wt pct, 44 atomic pct). The X-ray diffraction pattern for titanium was found in compositions up to TiB0.05_0.07 (1.1 to 1.6 wt pct); then, without a phase gap, superlattice lines appeared up to TiB0.8 On the other hand, Craighead, Simmons, and Eastwood' have estimated the solubility of boron in both alpha and beta titanium to be less than 0.1 wt pct, based on results of metallographic analysis. In some recent work done at Battelle, results were obtained which shed more light on the titanium-rich end of the titanium-boron system. Iodide-type titanium and high-purity crystalline boron were used in this investigation. The boron was prepared by hydrogen reduction of boron tri-bromide and deposition on a hot tungsten wire. The alloys were prepared by arc melting in an argon atmosphere of 10 cm Hg pressure on a water-cooled copper hearth. The ingots were hot rolled to strip at 850°C. Alloys containing up to 1 pct B could be hot rolled. Those containing 2 pct or more B could not be hot rolled. Metallographically, it was found that a second phase was present in alloys containing as little as 0.4 pct B, and that the quantity of second phase increased with increasing boron content. This is illustrated in Figs. la and lb, which show the microstructures of a Ti-0.4B and a Ti-1B alloy annealed in argon at 850°C. X-ray diffraction patterns of alloys containing 1 and 5 pct B revealed the presence of extra lines which correspond to the superlattice lines reported by Ehrlich.' However, no evidence was found of a shift in the lattice constants of alpha titanium indicating that there is very little, if any, solubility of boron in alpha titanium. This fact, coupled with the fact that the alloys were definitely two-phase, indicates that the extra lines are not superlattice lines, but are more probably the result of a second phase of a hexagonal structure almost identical in cell

Jan 1, 1952

By J. R. Long, T. R. Graham, C. W. Matthews, R. S. Dean

IN a previous paper§ the authors reported on the mechanical properties of a 65 per cent copper, 10 per cent manganese, 25 per cent zinc alloy as compared with similarly processed cartridge brass. Additional investigations by these laboratories, on higher copper alloys, have demonstrated that at lower zinc concentrations even larger amounts of pure manganese may be added to copper-zinc alloys without exceeding the single-phase solid solution limits, and that similar increases in tensile strength, yield strength, and hardness may be obtained without excessive decreases in ductility. Several compositions in this range showed also a decided color change with increasing manganese. The normal "brassy" color was considerably lightened and reduced to a faint yellow cast at 15 per cent manganese. With higher manganese contents the alloys were essentially white and similar in appearance to the nickel-silver alloys. From this work it appeared that it would be desirable to determine more completely the properties of the wrought and annealed white alloys. Accordingly, a more detailed study was planned of an alloy having the composition 70 per cent copper, 20 per cent manganese, and 10 per cent zinc. This alloy remained single-phase throughout the working and annealing cycles of the preliminary tests and appeared to be about the strongest of the white single-phase alloys. The project included also an investigation of additional alloys, deviating from this composition by 5 per cent of each of the three components to evaluate the effects of variation in composition; also a study of the properties of the central alloy made with silicothermic manganese. MATERIAL PREPARATION Electrolytic manganese, wirebar copper, and electrolytic zinc were used for the preparation of the alloys. Representative analysis of the electrolytic manganese seldom exceeds 0.01 per cent iron, 0.02 per cent sulphur and 0.02 per cent lead, with no silicon or aluminum. A typical sample of the silicothermic manganese metal contained 2 per cent iron, 0.81 per cent silicon, 0.i6 per cent carbon, and 0.36 per cent aluminum. Melting and alloying were performed in a high-frequency furnace with magnesia crucibles. Melts were deoxidized with small aluminum additions and cast into 25-lb. slab ingots. Care was exercised in deoxidation to avoid excessive amounts of residual aluminum, which has been found to have significant effects on alloys in this system. All ingots were hot-rolled at 1200° to 1300°F. and then cold-rolled with intermediate anneal-

Jan 1, 1945

By F. B. Plummer

THE practice of introducing acid into oil wells to increase production of oil and gas has been in use since 1894, when it was first used in the Pennsylvania. oil fields30.? It is only since 1928 that it has been used to any extent in the Mid-Continent18. The process has proved successful in increasing production, at least temporarily, in depleted oil fields where the producing formation is highly calcareous and where water drive is not too pronounced. In the Zwolle field in Louisiana, where the producing horizon is a chalk, increases of 100 per cent have been recorded25. In north-central Texas, where the oil is produced from the Marble Falls limestone, equally pronounced increases have resulted3. The production also in some fields yielding oil from quartz sand cemented with calcite has been benefited. The evidence of actual increase in total recovery of oil, however, has been questioned by some engineers18. It has been pointed out that the results of the treatment of a well in a new district, where the process has never been tried out, can never be predicted with certainty, since other factors besides percentage of calcareous content: of the oil sand play a large part in determining the success of the method. Numerous articles have been published on acid treatment and on the effects of acid on limestone1-35, yet very little has been written con-cerning experimental work on the actual effect, of acid on capillary pores and larger oil-coated voids of oil sands. This is due partly to difficulties in duplicating field conditions in a laboratory and partly to the fact that the process has been carried out largely by contracting companies that have been unwilling to publish details of their results for fear of loss of business to competitors. The authors, using equipment developed to measure the radial permeability of oil-sand cores29, have developed a method of investigating the results of acid treatment which has enabled

Jan 1, 1935

By W. A. Backofen

THE preferred orientations, or textures, resulting from many of the various methods for testing and forming metals have been the subject of numerous investigations.1,2* Despite this large amount of work, however, only a few limited studies have been made of the texture that is developed by torsional deformation. Ono3 found that in severely twisted wires of copper and aluminum a [Ill] direction lies parallel and a [1101 direction perpendicular to the longitudinal axis of the wire. Sachs and Schiebold4 have reported that a double-fiber texture exists in a twisted aluminum wire with both the [Ill] and [loo] directions parallel to the axis of the wire. Twisted iron wires have also been examined by Ono.8 Both the [1101 and [1121 directions were reported as parallel to the axis of the wire. Goss5 concluded from a study of twisted rods of a low-carbon steel that the preferred orientation existing at fracture is quite complex, but that many grains have a [1101 direction parallel to the axis of the wire. In addition to the earlier experimental work, some suggestions have been made about the possible nature of the torsion texture. These suggestions are based on the results of many experiments which indicate that the cold-working texture of a particular metal is largely determined by the geometrical change in shape that the metal undergoes during plastic deformation.1,6 Hibbard and Yen7 have considered the problem of deformation textures and have presented an analysis which is able to explain why equivalent changes in shape should yield similar textures. Therefore, a knowledge of the principal strains associated with torsional deformation would seem helpful in the interpretation of the torsion texture. The necessary analysis has been made of the state of strain in an element of metal lying in the surface of a cylindrical rod or tube that has been subjected to pure torsion.8,9 This analysis shows that the directions of the principal normal strains rotate continuously within a torsion specimen while it is being twisted. After the first infinitesimal amount of twisting, these directions make angles of 45" with the longitudinal axis of the bar. They rotate from this position as twisting proceeds, and after an infinite amount of twisting, the direction of the principal tensile strain is perpendicular, and the direction

Jan 1, 1951

By Thomas M. Drown

Theodore Dehon Rand was appointed Treasurer of the American Institute of Mining Engineers by the Council, at the Boston meeting of February, 1873, to fill a vacancy caused by the resignation of the treasurer who had been elected at the first meeting in Wilkes-Barre in May, 1871. He was elected by the Institute to this offce in the following May, and yearly thereafter until 1903. He often alluded with amusement to the abrupt way in which he was injected into this position, by my coming to his office and asking him to accept the appointment as Treasurer, on the ground that he was eminently fitted for the position by reason of his legal and business knowledge, his interest in geology and mineralogy, and more particularly because he was a neighbor of the person (to wit, myself) who was slated for the Secretaryship, and they could thus convenient.ly confer on Institute matters. He consented, on condition that the duties should not involve too.much additional work for him. This assurance was easily given, for the Institute then

Jan 1, 1904

By Kendall E. Born

Production of crude oil in Tennessee during 1944 was slightly more than 9500 bbl., about 1300 bbl. more than 1943. Approximately 8000 bbl. was produced from the "Mississippi lime" in Scott and Morgan Counties. Some half dozen wells in Clay, Pickett, and Fentress Counties, pumped intermittently, produced about 1500 bbl. This production is from rocks of Ordovician age ranging in depth from less than 500 ft. to approximately 1000 ft. Natural gas was marketed from wells in Morgan and Fentress Counties for consumption in the Sunbright and Jamestown areas, respectively. The production of oil by counties is shown in Table I. Developments There were 20 completions during 1944 totaling 19,615 ft., nearly twice as much as in 1943. One well was drilling on Dec. 31, 1944. Of the 20 completions, one was a small oil well soon abandoned. Three gas wells were completed which are used locally. The completions are listed in Table 2. The distribution of tests according to physiographic divisions is given in Table 3. Cumberland Plateau There were five completions in the northern part of Cumberland Plateau. One was a small gas well in the Cooper pool 3 miles west of Oneida, but an attempt to extend the pool to the south resulted in a dry hole. The most active area in the state during 1944 was the northern Cumherland Plateau, especially in Cumberland, Morgan, and Scott Counties. Several blocks, aggregating more than 500,000 acres, were assembled and leasing was continuing in the early part of 1945. Surface work has been, or is being, carried on by at least four companies. While in an area of past oil and gas production from the "Mississippi lime," the principal interest appears to be in the essentially unexplored pre-Mississippian possibilities. The Knox dolomite group of Cambro-Ordovician age is receiving some attention as a possible reservoir. As the year closed one well was drilling on a surface structure near Lantana, 6 miles southwest of Cross-ville. This test will be drilled into the upper part of the Knox. Late in 1944, it was planned to lay a gas line from northern Morgan County to Oneida in Scott County, a distance of approximately 20 miles. Middle Tennessee Fifteen wells were drilled in Middle Tennessee. In the northeastern Highland Rim area there were 11 completions, one

Jan 1, 1945

By Eugene H. Cowles

The German silver industry of the United States amounts in value to upwards of $6,000,000 or $8,000,000 annually. Several thousands of people earn a livelihood pursuing it, and the beautiful goods and articles manufactured from this time-honored and valued alloy are everywhere visible. German silver enters largely into our street signs, harness and house hardware, and all manner of table-ware, solid or plated. There is scarcely an hour in the day that German or nickel-silver is not before our eyes. The composition of this alloy is a very uncertain thing, and depends largely on the honesty of the manufacturer and the price the purchaser is willing to pay. It is composed of copper, zinc and nickel in varying proportions. The best varieties contain from 18 to 25 per cent. of nickel, and from 20 to 30 per cent. of zinc, the remainder being copper. The more expensive nickel-silver contains from 25 to 33 per cent. of nickel, and from 75 to 66 per cent. of copper. The nickel is used as a whitening element; it also strengthens the alloy and renders it harder and more non-corrodible than the brass made without it, of copper and zinc. Moreover, it reduces the odor emanating from brass, which is so disagreeable if it occurs about the dining-table. Of all troublesome alloys to handle in the foundry or rollingmill, German silver is the worst. It is unmanageable and refractory at every step in its transition from the crude elements into rods, sheets or wire. As a white-headed furnace-man recently said to the writer, in one of our large mills, " you can put eight crucibles into the fire, each containing exactly the same mixture of German silver, and when you take them out and pour them into slabs for rolling, seven will be a mass of scum or slag, or the stuff will swell up like rising bread and overflow the moulds, and be so full of blow-holes that it will look like a sponge. The eighth crucible will contain perfectly good metal. On remelting the next day, the bad stuff will, in nine chances out of ten, come out just as good metal as the eighth pot the day before, and under apparently the same conditions." With nickel at seventy or eighty cents per pound, German silver

Jan 1, 1890

By Robert H. Richards

The group of four papers on ore dreseing read at the Butte meeting, all of them dealing with the recent developments at the Great Falls and Washoe plants of the Anaconda Company, form an extremely important contribution to the subject of ore dressing. It proves the efficacy of the new hindered-settling principles first brought out in a paper entitled Close Sizing Before digging' and later elaborated in a paper entitled Development of Hindered-Settling Apparatus: and it is the first large demonstration on this class of mill that has been made. It must be very gratifying to all mill men to have these papers at hand, charged with careful investigations and results pointing to the conclusions reached; the papers cannot fail to be a great help to every designer of mills and to mill men who are working on this class of concentration. The papers have dealt with their subjects so completely and have demonstrated every point from beginning to end in each case so thoroughly it leaves little for the commentator to say in the way of criticism. Therefore it seems best to him to confine himself to adding a few points of history which he believes will be interesting to the readers. Referring to the paper by Mr. Wiggin, and to the fact that the Richards hindered-settling pulsator classifier was turned down, the writer wishes to say that this classifier was the first of its kind that had ever been introduced, and since that time it has undergone great developments which he believes would overcome the difficulties encountered in the test,. In fact, there was one test made at Great Falls which with the Wilfley tables and vanners brought all the tailings down to 0.36 per cent. copper except the fine slime. Since that time, and since the classifier has been further developed, in one Colorado mill it proved a wonderful amalgam catcher, catching in all

Jan 1, 1914

By E. E. Gardner, P. A. Schumann

A description of a new four-point probe configuration which permits measurement of epitaxial layer resistivity is given. An analytic solution to the potential distribution due to a point current source on a multilayered structure is briefly described. Typical solutions for this probe configuration are presented. Probe spacing, layer thickness, substrate resistivity, and substrate thickness enter into the calculation. Correction factors for typical cases are given. A brief description of the construction of a probe which can achieve a small spacing of 15 is presented. The prohe is constructed so that all points are adjustable by micrometers and the probe spacing and configuration can be easily altered. Measurements of layer resistivity with the four-point probe are compared with those taken with the three-Point probe and diode-capacitance techniques. TWO techniques of obtaining profiles of N/N+ epitaxial structures are given. The reproducihility of the probe spacing and resistivity measurement is discussed. The effects upon the resistivity measurement of errors in the measurement of the lager thickness, substrate resistil)itv, and substrate thickness are presented. SINCE its introduction by valdes' in 1954, the four-point probe has been the most widely used tool for determining semiconductor resistivity. Its usefulness ranges from the evaluation of bulk semiconductor ingots to the characterization of impurity profiles in diffused structures. In general the four points, two current probes and two potential probes, are placed on one surface of the material being tested either in an in-line array or in a square array. Numerous correction factors1 8 have been worked out for these configurations which are dictated by the finite geometry of the sample being tested. One method of evaluating thin wafers has been proposed which has two probesg on each side of the wafer. Further modifications have added a fifth'' and a sixth" probe. One paper1' has discussed the accuracy of the four-point probe and the precautions necessary in its use. With the exception of the method where two points are placed on opposite sides of the wafer, the four-point probe is restricted to evaluation of wafers with a homogeneous resistivity or to the case where an isolating junction exists between the substrate and the layer (epitaxial or diffused) being evaluated. Due to the relative resistivities and thickness, the resistance of the epitaxial layer is much greater than that of the substrate, and consequently a majority of the current flows through the substrate. The potential distribution at relatively large distances from the current sources is determined by the substrate resistance, and hence the AV/I value is a measure of the substrate resistivity and not that of the epitaxial-layer resistivity. In the immediate vicinity of a current source the potential distribution is determined by the layer resistivity among other factors. Consequently, if the potential probe is placed very close to the current source, then with appropriate correction factors it is possible to determine the layer resistivity. This was the theoretical basis for using two closely spaced probes on opposite sides of an epitaxial wafer. However, due to mechanical problems, it is desirable to place the four probes on the same side of the wafer. This paper discusses the potential distribution in

Jan 1, 1965

By P. S. Rudman

Crystal-structure occurrences in binary phase diagrams of fifth- and sixth-period elements, zirconium through palladium and hafniun through platinum, are surveyed with the conclusion that average .group number GN is the dominant correlative. This is interpreted in terms of curves of enthalpy differences between competitiue structures that are continuous func -tions of GN. It is further reasoned that the absolute formation energies may also be continuous functions of GN and if so can be simply obtained from the regatives of the heats of sublimation of the elements. It is shown that from such a heat of formation-GN plot the heats of mixing of alloy systems can be quantitatively predicted. For example, for sixth-period alloys very large exothermic heats of mixing are predicted for systems that span GN = 6 (i.e., Hf-Pt, Ta-Os, ...). Thermodynamic data with which to test these predictions do not appear to be available. If in the latter transition (A subgroup) elements we eliminate from consideration the fourth period where magnetic terms contribute to crystal-structure stability, as shown in Table I, there is a very regular sequence of structures. Using the group number (GN) assignments of Table I, which differ from the usual assignments of 8 to the elements listed as 8 through 10, it is perhaps trivial to say that the phase occurrence is a unique function of GN. However, the interesting aspect of alloys from among these elements is that the alloy structures also appear to correlate with GN. The GN for an alloy is given as GN = SixiGNi, where xi and GNi = atomic fraction and GN of component i, respectively. It is difficult to credit anyone in particular with having discovered this correlation, so many people have implicitly or explicitly employed it in the last 10 years. However, Bloom and Grant' in their correlation of s-phase occurrence with total number of d + s electrons were certainly one of the first to appreciate the correlation and Hume -Rothery2 appears to be responsible for the use of average GN as defined above. Only in the last few years have the phase diagrams of enough alloy systems been determined for this correlation to be surveyed with any degree of completeness. We shall here, in an abbreviated format, summarize the available phase-diagram literature and discuss some consequences of the GN correlation. BINARY DIAGRAM SURVEY In Figs. 1 to 3 the phase occurrences are summarized. In Fig. 4 the occurrence limits for the more common structures are summarized. That the GN of an alloy falls within the occurrence limits of a particular structure is a necessary but not a sufficient condition for the appearance of that structure. The preceding figures certainly illustrate that GN is a dominant correlative for structures of these elements. Many of the diagrams have complications, with ordering and other phase changes occurring in intermediate phases, that cannot be clearly accommodated in such a schematic survey and have hence been left out. Such omissions cannot, however, negate the GN correlations discussed here. Relative atomic size is also an important crystal-structure determinant and since atomic size varies quite regularly with GN for these elements it is possible that the apparent GN correlation is basically a size correlation. In Fig. 5 relative size occurrence limits are given for intermediate phases and extended terminal solutions. The relative volume, ?v/(v) - 2(vA - vB)/(vA + uB), has been taken as the measure

Jan 1, 1968

By Campbell M. Hunter

Petroleum is found in almost every province in Persia. On the northern frontier, along the southern shore of the Caspian Sea, it is found near Enzelli and Shakhtesar and gas at Khoremabad. Oil is also found at Gumish Tepe, northwest of Astrabad, on the southeastern shore of the Caspian Sea. Further inland, to the south of Astrabad, oil is found at Dehahkuh-i-balae, also on the margin of the Khorasan desert at Semnan, 115 mi. (35 m.) east of Teheran. Along the western frontier, from northwest to southeast, oil is encountered at Ouschachi, north of Lake Urumieh; in the province of Azerbaijan, at Zohab, Khanikin, and other places in. the district of Kormanshah in the province of Ardelan. Further south, in the province of Luristan, oil is found east of Mendeli and in the Pusht-i-kuh districts. Considerable quantities of oil are also obtained from Schuster, Maidan-i-Naphtun, Ram-Hormuz, Beheban, which are almost on a straight line, running northwest and southeast along the foothills of the Bakhtiari Mountains. At Ahwaz, in the province of Arabistan, oil has been found along another range of hills whose axis also lies in a northwest-southeast direction. In the Fars province, boring for oil has taken place at Daliki, and indications of oil are found at Kheri, Fasa, Darab, and other places. A gas show is also recorded at Kuhi-Sung-Atush in this province, 30 mi. (48 km.) east of Darab. In the south of Persia, oil is encountered on Qishm Island, also at Ahmedi and other places north of Bunder Abbas. On the southeastern frontier, oil is found on the Sarhad range of hills. Thus, oil indications have been noted over a distance of approximately 1100 mi. along the western and 700 mi. along the northern frontiers of Persia. History The first working of oil in Persia of which there is any record took place at Kir-ab-US, Susiana, now known as Kiab, about 57 mi. northwest of Schuster. Herodotus (about B. C. 450) reported a well near Ardericca that produced three different substances; namely, asphalt, salt, and oil. The oil, which was black and had a strong smell, was called Rhadamance by the Persians.

Jan 1, 1921

By V. C. Allen

THE Tri-State Zinc, Inc., Galena, Ill., was confronted with the problem of securing ore from a deposit because the hoisting shaft was several thousand feet from the mill. The orebody is several thousand feet long, averaging 200 ft in width and 60 ft in height and opened up by vertical shafts some 300 ft deep. Mining is by the room-and-pillar method. During the initial operation the ore was loaded by conventional electric 1/2-yd boom-and-dipper shovels and hauled to the shaft by 8-ton diesel trucks. This underground ore loading and hauling was well adapted to the conditions and productive of low costs per ton. However, with the mill situated as mentioned, a triple handling of all broken rock was necessary: l—from the stope to the shaft by truck, 2—up the shaft by skip br can into the surface hopper, and 3—by truck from the surface hopper to the crushing plant at the mill. In addition to the repeated handling, serious troubles were encountered during the winter because of freezing in the shaft hopper. Consideration was given to either moving the mill to the new orebody or to the construction of a second mill. The presence of other orebodies to be mined at a later date made the first alternative impractical while the capital outlay for a second mill, when the present plant of approximately 850 tons per day was deemed sufficiently large for the total reserves, made the second alternative also unwise. It was decided to retain the mill in the originals location and continue to move the ore to it. The idea of driving an inclined adit from the surface to the bottom of the orebody suitable for truck haulage and big enough to allow the passage of all mechanical equipment was conceived. Among the apparent advantages of such an incline were: 1— Direct haulage from the stope to the mill without rehandling. 2—Elimination of virtually all grizzlies. Trucking from underground to the mill would do away with all hoppers, chutes, gates, and skips and make the maximum rock size dependent solely on the size of the shovel dipper at the mine and the crusher opening at the mill. 3—Less secondary blasting would be needed. 4—Ease of transporting equipment and supplies underground. Shovels and trucks could be taken through the incline intact. 5—Equipment could be brought to the surface for repairs and servicing without loss of time. The same advantages of ease in moving would be present in the handling of men, steel, powder, and supplies. 6—There would be far less difficulty in increasing the amount of tonnage that could be moved by truck up an incline than would be found in attempting to increase the capacity of a shaft. 7—All the broken ore in the stopes would serve as bin capacity, as it would take the breakdown of all of the loading and hauling equipment to have the same effect as a delay in shaft hoisting. 8—All danger of men being trapped in the mine as a result of shaft fire or power stoppage would be eliminated. 9— Virtually all trouble from severe winter conditions would be eliminated by the direct haul underground to the mill. The decision was made to proceed with the driving of an inclined adit. The topography of the surface between the orebody and the mill was such that it was possible to locate the portal at a point 170 ft above the mine floor and 1800 ft horizontally from the central point of the orebody to the south and 2500 ft from the mill to the north. A grade of 10 pct was found to be optimum for continuous truck haulage when the various factors of speed, safety, and truck maintenance were all considered. The incline as driven was consequently 1700 ft long on 10 pct grade and 12 ft high by 17 ft wide in cross section. The tunnel-driving equipment was chosen so that it could be used in mining after the completion of the tunnel. Drilling was done with a jumbo with two Joy jibs mounting 3-in. drills, loading with an Allis-Chalmers diesel-powered, front-end loader of approximately 11/4-yd capacity, and hauling by Koehring Dumptor trucks of 8-ton capacity, diesel-powered. The width of the tunnel allowed the end loader and Dumptor to be placed abreast. Since the Dumptors can be driven either forward or backward with equal facility, loading was accomplished without turning around either machine throughout the loading operation. The crew in addition to the tunnel foreman was comprised of three men per shift at the start and in the later work, four men. Each crew could perform any part of the working cycle. If the drilling was completed and the round blasted in the middle of a shift, the same men would proceed with the loading and hauling. Since the mine already had been drained to the bottom levels, no water was encountered. At the halfway point the tunnel was widened for approximately 100 ft to permit trucks to pass. The total cost of the tunnel excluding the capital outlay for equipment, which was all continued in use in the subsequent mine operation, was $60,363.00 or $35.50 per ft. The tunnel was completed at the end of June, 1949 and has been in continuous use since that time. In the five months from July to November inclusive, 106,049 tons have been transported to the mill or an average of 835 tons per day. No unforeseen disadvantages have been encountered and the advantages which had been predicated before the adit's construction have been more than realized. As previously mentioned, the deposit is worked by the room-and-pillar system with occasional faces up to 125 ft high. Except in driving development drifts when diesel-powered, front-end loaders such as were used in the tunnel are employed, all shoveling is done by Yz-yd boom-dipper type shovels electrically driven. These units need a width of 25 ft and a height of 14 ft in which to operate. All hauling is by diesel trucks, mainly Koehring Dump-tors. Roads are maintained with caterpillar tractors and a road grader. The tonnage output from the

Jan 1, 1952

By Pol Duwez, Spencer R. Baen

A LTHOUGH the practical importance of Fe-Cr--iV Mo alloys has long been recognized, constitution studies have been limited to a few alloys within rather narrow ranges of composition. The purpose of the present study was to establish the phase boundaries in the ternary diagram at a temperature of 1200°F (650°C).* The identification of phases and the determination of phase boundaries were based primarily on X-ray diffraction measurements and occasionally on microscopic observation. The methods used for locating the phase boundaries were essentially those described in detail by Andersen and Jette,' and by others.', The compositions of 180 alloys, prepared by powder metallurgy techniques, are shown in Fig. 1. The chemical analysis and mesh size of the powders which were used for the preparation of the alloys are given in Table I. The powders were mixed for 48 hr or longer, then compacted under 80,000 psi in a %-in. diam steel die. Each specimen weighed approximately 5 g. The compacts were sintered for 4 hr at 2500°F (1371°C) in an atmosphere of pure dry hydrogen (dew point near the temperature of liquid nitrogen). An open tray of chromium powder was placed upstream of the compacts to act as a "getter" for the last traces of oxygen or water vapor. In many cases this chromium powder was bright after sintering. Occasionally the upstream side of the powder was slightly greenish, but in all cases the downstream side was metallic. Some of the alloys contracted during sintering and some expanded as much as 20 pct. The latter alloys, which in all cases were brittle, were crushed in a tool steel mortar, repressed, and resintered for 4 hr at 2500°F. After sintering, the alloys were aged for ten days at 1200°F (650°C) in evacuated (105 mm Hg or better) fused silica tubes and were cooled rapidly to room temperature following the aging treatment. The use of the powder metallurgy technique in preparing alloys for structural investigation offers a simple method 'of avoiding contamination or non-homogeniety which could result from a melting operation. It is very often possible to dispense with chemical analysis of the alloys which have been prepared by the powder metallurgy method. In lieu of chemical analysis, it is necessary to determine the weight of the compact before and after sintering. The chemical composition of the alloy may be considered as that of the green compact, within the limits of accuracy determined by the loss of weight during sintering. In phase-diagram studies it is important to achieve homogeniety in structure, whether the alloys are prepared by powder metallurgy or by melting. Homogeniety means complete diffusion during the sintering of the alloys which are prepared by powder metallurgy. It has been found from experience that the best criterion for establishing the completeness of diffusion is the sharpness of the X-ray diffraction patterns. This criterion has been used throughout the present study. The X-ray diffraction data were obtained using powder cameras of either 214.86 or 71.62 mm diam. Copper, cobalt, or chromium Ka. radiation was used, the choice being based on the alloy composition. The powder samples were obtained by filing or crushing, depending on whether the alloy was ductile or brittle. In some cases, the powder was annealed for 4 to 6 hr at 1200°F in vacuum. The measurements were corrected for film shrinkage and absorption. The large camera, in which the film is mounted

Jan 1, 1952

By T. R. Ingraham

The thermal decomposition of cupric sulfate and of cupric oxysulfate has been examined by deter-mining the equilibrium gas pressure generated over each pure compound. The equilibrium data have been used to calculate the thermodynamic properties of both compounds, and the results have been combined with previously published data to establish a predominance-volume diagram for the Cu-S-O system over the normal range of roasting temperature and gas composition used in the treatment of copper minerals. Copper oxysulfate recrystal-lizes at 1100°K with an apparently irreversible en-dothermic heat requirement of 2.9 * 0.3 kcal per mole. WHEN mixed sulfide minerals containing copper are roasted, either of two procedures may be followed, depending on the nature of the other metals. In the first procedure, the roasting is controlled to produce a maximum amount of water-soluble copper sulfate which may be removed selectively from the water-insoluble compounds of the other metals. In the second, control is directed toward the production of water-soluble sulfates of the other metals and an insoluble salt of copper. Effective control of either of these processes would be enhanced by knowledge of the thermal stability of cupric sulfate and of cupric oxysulfate. In this paper, established data for the thermal stability of cuprous and cupric sulfide and of cuprous and cupric oxide will be combined with new data for the therma1 stability of cupric sulfate and cupric oxysulfate, to designate the volumes of stability of the significant compounds in the Cu-S-O system in the temperature range 750° to 950°K. EXPERIMENTAL Materials, Apparatus, and Procedure. The copper source material used in all experiments was Fisher Certified Reagent Grade "anhydrous" cupric sulfate, for which the following analysis was supplied by the manufacturer: chloride, 0.002 pct; alkalies and earths, 0.2 pct; insoluble, 0.002 pct; iron, 0.020 pct. Cupric oxysulfate was prepared from the normal sulfate by two procedures. In the first, equimolar quantities of cupric oxide (prepared by decomposition of the sulfate) and cupric sulfate were ground together and heated under vacuum in a sealed silica vessel at 800°C. This procedure was subject to failure because of explosion of the silica vessels due to the pressure of the final traces of water released from the sulfate on the initiation of its decomposition. The second procedure involved roasting the cupric sulfate, with frequent rabbling, in a muffle furnace at 725°C for a period of 48 hr. This produced an excellent product, which was confirmed as copper oxysulfate by X-ray and chemical analyses. The experimental technique used was that of measuring the total pressure exerted by the sulfur trioxide, sulfur dioxide, and oxygen produced by the following reactions: 2 CuS04 = cuo • CuSO4 + SO3 [1] cuo . CuSO4 = 2 cuo + SO3 [2] SO3= SO2 + 1/2 O2 [3] The apparatus used in the experiments has been described previously.1-3 Its main feature of a U-tube mercury manometer in which the mercury is protected from corrosion by enclosure in a flexible Pyrex bellows. Before beginning a run, the interior of the apparatus, including the bellows-manometer and all connecting tubing, was thoroughly washed with hydrochloric acid and distilled water to remove any

Jan 1, 1965

By David Cornell, Yusuf K. Sukkar

The fundamental differential equation for fluid flow has been rearranged, integrated numerically for natural gases, and the results presented in tabular and graphical form suitable for the direct calculation of vertical gas flow problems. The integration is rigorous except for the use of a constant average temperature. Both static and flowing bottom-hole pressures may be calculated by (his method without resort to trial and error procedures. INTRODUCTION Bottom-hole pressures can be determined either by direct measurement with a bottom-hole pressure gauge or by calculation. Since measurement with a bottom-hole pressure gauge is costly, calculation of bottom-hole pressures is to be preferred when possible. Calculation involves knowledge of the wellhead pressure, the properties of the gas, the depth of the well, the flow rate, the temperature of the gas, and the size of the flow line. These quantities must be combined in a suitable equation for vertical flow. Several equations have been developed for the purpose of calculating gas flow through both horizontal and vertical pipes1,2,4,5,6,7,8,9 These equations all have the basic differential equation for flow as their starting point. They differ only in the assumptions which are made in order to simplify the integration step. The bottom-hole pressures calculated using any of the better known equations are in good agreement with bottom-hole pressures calculated by a more rigorous but considerably more tedious stepwise integration method. All of these methods, however. require a trial and error solution for the calculation of flowing bottom-hole pressures. The purpose of this paper is to present a method which provides a direct solution of static and flowing bottom-hole pressures without use of a trial and error solution. At the same time the method involves fewer simplifying assumptions than any of the previous methods used, except lor the lengthy stepwise method. The derivation of any practical flow equation begins with the basic differential equation which is rigorous for almost all flow problems. The five terms in Equation 1 represent the potential energy, the potential energy of position, the kinetic energy, the shaft work done, and the energy losses due to motion of the fluid respectively. Equation 1 reduces to Bernoulli's theorem for the case of horizontal flow of an incompressible fluid, no work done, and no energy losses due to friction. In the present case, the term (v) (dv)/(g,.) can be shown to be quite negligible compared to the other terms, and is therefore neglected in the derivation. The term — dws includes work done by a pump or turbine in the system and is zero in this case. The frictional losses in the pipe are included in the term — d(lw) which is expressed in terms of the Moody friction factor as in Equation 2. (f) (v2) (dL) d(lW) = (f)(V2) (dl)/(2) (g) (d) The specific volume of a gas can be expressed in terms of the temperature, pressure, molecular weight, and compressibility factor. The velocity of the gas can be expressed in terms of the weight rate of flow, the specific volume, and the dimensions of the pipe.The reduced pressure Pr is to be used because z can be expressed as a function of Pr and Tr alone for most natural gases:

Jan 1, 1956

T.B.King (Depaytment of Metallurgy, Massachusetts Institute of Technology)— A valuable contribution of the authors is in the factual information which they have been able to gather; this type of information is quite difficult to obtain. In many respects, however, it would have been better if they had not subsequently embarked on a discussion of the chemistry of the converter process. It seems inconceivable that the authors do not refer to the papers of Schuhmann and his associates14 which have set the thermodynamic foundation for the whole copper smelting operation. In addition, a very useful review on the physical chemistry of copper smelting by Ruddle 5 appeared as long ago as 1953. An examination of this literature would have convinced the authors that there is no cause to be surprised at a correlation between the magnetic content and the silica content of converter slags, though they rightly point out that one should distinguish between the total magnetite content of the slag and the amount of magnetite which may be considered to be in solution. It is not true that the lowest melting converter slag is that corresponding to the eutectic between ferrous oxide and silica. The simplest slag system which can be considered is a three-component system, since both ferric and ferrous iron are present. As Schuhmann, Powell, and Michal have shown, there are lower melting compositions than this eutectic in the ternary system. The most unfortunate impression given by this paper is that the driving force for chemical reaction is determined by the heat of reaction: of course the entropy change must be taken into account. It would have been more correct to list, in Table VI, values for free energies of formation. Nor can it be said that the data in Table VI represent the "best available data." They do not corregtond with any of the recent, acknowledged sources. F. E. Lathe and L. Hodnett(author's reply)— We are pleased that Dr. King finds the factual information in our uawer of some interest. Dr. King suggests that it would have been better if our analysis and discussion of the data had been omitted, largely because our list of references is so. incomplete. If he will carefully read our introduction, he will see that the questionnaire was sent out in the hope of obtaining data which would throw light on certain questions relating to the use of converter refractories. We did not attempt (nor would the AIME have published!) a complete review of the literature on copper converting, as Dr. King has apparently assumed, nor indeed a complete analysis of the data submitted, but tried only to find a sound basis for the choice of refractories, taking into consideration common variations in converter practice. We hope our paper indicates that, by raising the silica content of the converter slag and operating at a higher temperature, the normal circulating load of magnetite can be greatly reduced, and the whole reverberatory-converter operation improved to a major degree, with resultant important savings. Under such operating conditions, chrome-magnesite brick may be expected to stand up better than those of straight magnesite. Regardless of the choice as between these brick types, however, we find the cost of converter refractories to be so low in comparison with other converter costs as to justify operation under the more severe conditions suggested. Valuable as are the papers by Schuhmann and associates and the book by Ruddle, we make no apology for omitting reference to them, nor for using heats of reaction without mention of entropy changes or free energies of formation. Our primary object was to interest the practicing copper metallurgist, with whose language we may claim to be fairly familiar; we think it would have been unwise to include the highly theoretical phases of the subject which Dr. King suggests. The interest shown in our preliminary paper presented at the New York meeting in 1956, and the trends in practice whtat we have observed since that time, suggest that we did not wholly miss the target. In conclusion, we sincerely hope that Professors King and Schuhmann will independently review the data obtained in our questionnaire and submit a paper giving their own recommendations as to the choice of refractories and the particular converter operating conditions which will result in the lowest overall cost of copper smelting and converting.

Jan 1, 1960

By Albert Stazicker

AT Climax the warehouse department operates as an independent unit similar to the mine and mill departments. It has the responsibility of receiving, checking, unloading, and storing all material and supplies delivered to the plant. In addition, the transportation of all supplies comes under the direction of the warehouse so that prompt delivery of supplies to all departments is one of its major functions. The transportation division operates heavy and light trucks, trailers, two large tractors, and two snowplows. In addition to delivering supplies it is also responsible for snow removal from the roads, hauling of sand and gravel for concrete and domestic coal to employees. and all miscellaneous work involving the use of tractors or trucks.

Jan 1, 1946

By Albert Williams

A large proportion of the work performed in wet-crushing silver mills is devoted to the handling and re-handling of pulp between the battery and the pans. There seems to be no generally applicable substitute for the settling-tanks, and in the present system of constructing mills the tanks involve an amount of labor which may be regarded as disproportionate and unnecessary, in view of the automatic improvements which have been introduced in other directions. This diffculty has been met, however, by Boss's continuous process, in which the pulp flows directly from the mortars to the first of a series of constantly working overflow-pans. This method has been adopted at the Noonday mill, Bodie, California; the Harshaw, Arizona; the Sierra Grande, New Mexico ; and the Prietas, Sonora. The continuous process, while giving excellent results with special ores, and under peculiar local conditions (such as a deficiency in water supply), is not, I believe, claimed to be available for all raw-amalgamating mills, notwithstanding its well-merited popularity for certain work. Some trouble has been experienced from the tendency to concentration in the pans, though this can be avoided by skilful manipulation. It has also the disadvantage inherent in combinations of distinct operations ; it requires a very nice adjustment of the water supply to obtain full battery efficiency without running the pans too thin, though the latter defect is partially compensated for by the gradual thickening of the pulp as it proceeds through the series of pans. The objection is similar to that which holds in a parallel duplex process, that of combining roasting and smelting in a single furnace, where each operation is injuriously affected by the necessity of fitting it in with another and entirely different one.

Jan 1, 1883

By R. J. Miller, W. A. Bates

ALTHOUGH cresylic acids have been standard frothers in flotation for many years, there has been little discussion of their nature in the metallurgical literature. Aside from references in the patent literature, the paper by Landolt, Hill, and Lowy1 in 1930, which presented a study of the frothing and collecting properties of some of the constituents of crude cresylic acids, represents the only contribution of this type. The close froth control required in the delicate selective separations of present-day flotation operations have required the flotation metallurgist to choose his frothers with care, and have caused him to require of the manufacturer a closely controlled, uniform product. A background of knowledge of the chemical composition and physical and chemical properties of the frothers, by which their action may be correlated, should aid in selecting frothers for particular flotation requirements. Further, the recent almost complete replacement in flotation of coal-tar cresylic acids by those derived from petroleum makes it especially desirable to review the flotation behavior of the acids from the old and the new sources. In view of these facts the Milling Methods Committee of the A.I.M.E. suggested to the Oronite Chemical Co. of San Francisco the preparation of a paper on the subject, and this paper has accordingly been prepared as a contribution by the California Research Corporation, the research affiliate of the Oronite Chemical Co. The discussion is from the following aspects: (I) constitution and properties; (2) sources; (3) comparison of coal-tar and petroleum cresylic acids ; (4) characteristics as frothers, with particular reference to the effect of the substitution of petroleum acids for coal-tar acids. CONSTITUTION AND PROPERTIES Cresylic acids are commonly regarded as mixtures of orthocresol, metacresol and paracresol. This was, indeed, the former meaning of the term, but in recent years it has been loosely applied to any mixture of alkyl phenols boiling above 190°C.; that is, excluding only phenol itself. This means that cresylic acids, as they are known today, may consist of mixtures, not only of the three isomeric cresols, but of six xylenols and of a variety of higher boiling homologues. Generically the constituents of cresylic acids are alkyl phenols, and they are often so designated in the literature to avoid the more indefinite term, "cresylic acids." They form an homologous series starting with phenol, which has the familiar benzene ring, with an hydroxyl group in place of one of the hydrogen atoms. The series of alkyl phenols is formed by the substitution of alkyl side chains, such as methyl, ethyl, propyl, butyl, etc., for hydrogen

Jan 1, 1946

By R. W. Raymond

THE Brüclrner roasting-cylinder is well known as an apparatus which has done good work in the desulphnrization, particularly of refractory silver ores, in the western districts of this country. A paper by Mr. J. M. Locke, of Cincinnati, describing the cylinders, as constructed by Messrs. Lane & Bodley, in that city, may be found at p. 295, vol. ii., of the Transactions of the Institute; and a paper by Mr. N. H. Cone, vol. iv., p. 226, gives an account of their operation in Colorado. The purpose of the present paper is to present an .improved construction, designed by Mr. Brückner. This is clearly shown in the accompanying plate, which scarcely needs explanation. It will be seen at once that this construction involves two cylinders, instead of one. Mr. Brückner thinks that three cylinders might be better yet, as securing an exact mechanical reproduction of the work of the well-known three-hearth Fortschaufelungsofen, the most perfect of the reverberatories in which delicate roasting is performed with hand-labor. THE APPARATUS. Erection of the Cylinders.—Although the cylinders may he put lip at any locality, or added to existing works, it is preferable, if possible, to choose the site on a hill sloping naturally, say about 30' or 33. Two excavations are made, one 8 to 12 feet higher up than the other; and each is protected by a wall with a batter of about 1 inch to the foot, to prevent slides of stone and earth. Each cylinder being 20 feet long and 7 feet in diameter, the total excavation should be 60 to 70 feet along the hill, and 15 to 25 feet wide. On each level a building is erected 35 feet long by 20 feet wide and 12 feet high, with the roof containing a ventilator against the hill. When both buildings are on the same level, there should preferably be a solid frame-work of very heavy timber, to carry the four rollers which bear the upper cylinder. The four rollers carrying the lower cylinder should preferably rest on two very heavy pieces of timber, strongly braced together and laid to their top in a foundation made of stone or brick and cement. Foundations are necessary only under each two opposite rollers, but they must be made carefully,

Jan 1, 1886