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By AIME AIME

SHORTLY after graduation from Girard College, Francis B. Foley found employment in the open-hearth department of The Midvale Steel Co. later joining its research department. After twelve years with Midvale he became a professor in the department of metallography of the University of Minnesota. With the coming of the World War, he was called upon by the War Materials Investigation Committee to work on the manganese problem. In 1918, he took charge of the iron and steel division of the U. S. Bureau of Mines, at Pittsburgh, and. after a year of co-operative study of carbon steels with the late Henry M. Howe, was assigned to the Bureau's stations at Minne-

Jan 1, 1937

By Jacek Paraszczak

Numerous problems encountered in the mining of narrow vein deposits challenge the productivity, competitiveness and profitability of many mines. Mechanization of mining operations is one of the most important means to ensure the healthy survival of this mining sector. Vein deposits account for nearly all the world's primary silver production, as well as a significant portion of gold, tin, copper lead and zinc. In North America, narrow vein mining constitutes an important sector of the industry. Operators exploiting such deposits are concerned with the most appropriate mining method and equipment to mine in such a way as to minimize waste rock dilution. Unfortunately, most of the equipment available does not meet the additional geological and economical restrictions typical of narrow vein mining. Thus, mining these deposits is labor intensive and can result in low productivity. Consequently, the profitability of many such mines is reduced. Increased mechanization is one of the solutions to ensure their healthy survival. This paper reviews the state-of-the art in mining equipment with reference to narrow vein mining limitations. Problems encountered Geological conditions and economical factors have a decisive impact on the choice of mining method and equipment. Many ore bodies are relatively small, usually erratically distributed, often less than 2 m (6.5 ft) wide, with dips ranging from 0° to 90°. To make things worse, ore body limits are sometimes difficult to determine and the ground is hard and abrasive.

Jan 1, 1992

By João Geraldo Alves

A qualidade interna das placas obtidas no lingotamento contínuo é afetada pelas características do escoamento do aço líquido no distribuidor. O modelamento matemático é uma ferramenta muito utilizada para estudar o escoamento do aço líquido e a eficiência do uso de modificadores de fluxo na separação de inclusões do aço no distribuidor. O objetivo deste trabalho é determinar, através da modelagem matemática, uma configuração de barragem e dique que possa proporcionar uma melhor qualidade do aço lingotado. Essa modelagem utiliza recursos do software comercial ANSYS CFX, que é um software baseado no método dos volumes finitos para a solução de problemas da dinâmica dos fluidos computacional (CFD – Computational Fluid Dynamics). A utilização de barragens e diques permitiu uma melhora significativa nas condições de escoamento do aço, o que possibilitará uma melhor flotação e separação das inclusões, com um aumento no tempo de residência do aço no distribuidor, quando comparados com o projeto do distribuidor atualmente em uso.

Jul 30, 2018

Taking the third meridian as the eastern boundary of proved payable auriferous country, there is a stretch of country, nearly 600 miles in width, in which no appreciable amount of gold has yet been discovered. Many prospectors have attempted to .penetrate or traverse it, but comparatively few have thought it worth while proceeding with the examination.The desolate stretch of waterless desert-the very few and insignificant outcrops through the sand and the almost total absence of feed for horses have, combined, presented such a barrier as to preclude prospecting. The few who have traversed the country are eloquent in denunciation, yet their investigations, necessarily hurried, are not quite satisfactory. The absence of water utterly debars a thorough examination being made. Gold may exist in quantity, yet it would have to be extraordinarily plentiful to render its obtaining profitable. Too fantastic is the idea of its ever being a mining district; shifting sand to traverse, utter absence of wood and water render the notion absurd. Likely looking belts occur, but these in all "cases are small and remote from water. Gold has been obtained from likely look ing quartz reefs, but only by fire assay, and then but a few do to the ton. Without wishing to be pessimistic, I would unhesitatingly declare that east of the third meridian, and between the parallels 25 and 30 degrees in West Australia, there is no gold in payable quantities.

Jan 1, 1901

By G. P. Conard, E. H. Rennhack

The generation of fibers composed of individual TiZn15 compound particles and their influence on crystallographic orientation in chill-cast, hot-rolled hypoentectic Zn-Ti alloys were explored. Metallo-graphic examination and X-ray diffraction data show that such fibers form a planar network after 50 pet reduction which eventually tends to suppress twinning at some critical reduction level (-90 pct) where the grain size approaches the interfiber, spacing. This leads to the development of a duplex-type projerred orientation through slip rotation consisting of an al-most ideal (0001)(2iiOj texture and a (0001) (1010) rotated component. Correlations between basal-plane rotation and secondary- creep rc11e sugg-est, however that prejerred orientation does not contribute in a major way to the creep resistance of these alloys. EFFORTS to improve the creep resistance of zinc through alloying without incurring a loss in fabricating properties have achieved only minor success with the exception of the very effective addition of titanium. Anderson, Boyle, and Ramsey,l for example, demonstrated that increasing the amount of thiselement from 0.05 to 0.23 wt pct produced a progressive, 45-fold increase in the inverse creep rate of hot-rolled

Jan 1, 1967

By Q Liu, P D. Katsabanis

The energy output of crushed AN/FO, crushed AN/FO mixed with Aluminum (5%, 6.4% and 9.4% A1 by mass) and a commercial emulsion explosive has been measured using a detonation calorimeter. The charges had a diameter of 10 mm and were heavily confined by a 11 mm thick copper shell. In order to achieve stable detonation glass microballoons were used in the explosives so that the density of the AN/FO charges would be around 1.1 g/cc. The charges were detonated in vacuum and the detonation products were analyzed using gas chromatography. It was found that energy values were very close to calculated values obtained by ideal detonation codes.

Jan 1, 1993

By Gilles Carrière

"The Suffield mine is situated five miles southwest of the city of Sherbrooke, in the Eastern Townships of Quebec. lt is the property of Suffield Metals Corporation Limited, a wholly owned subsidiary of Ascot Metals Corporation Limited.The old Suffield or Griffith mine had been worked intermittently from 1863 to 1906, without ever producing much ore. In 1951, diamond drilling done by Ascot Metals proved over one million tons of ore in three new bodies. The average grade of this ore was 0·018 ounces of gold per ton, 2-40 ounces of silver, l ·28 per cent copper, 0·59 per cent lead, and 6-45 per cent zinc. Since then the mine has been active, producing between 300 and 700 tons daily. More recent exploration has found continuations of the ore zones.General GeologyThe ore of the Suffield mine is found in porphyritic rhyolites of the Sherbrooke group (Silurian), at or close to its contact with sediments of the Beauceville group (Ordovician). The contact shows pronounced folds as well as irregularities due to erosion of the sediments prior to the outpour-ing of the lavas. On surface the general strike is north, and the dip is steeply east.The footwall sediments consist of interbedded black graphitic slates and. dark-coloured chloritic quartzite, overlain in many places by a thin bed of magnetite-hearing quartzite.The rhyolite host rock is a light grey rock, containing very abundant quartz and feldspar phenocrysts in a microcrystalline matrix of the same minerals. Some sericite is always present, especially in the vicinity of the ore zones, where the rock shows a pronounced schistosity.Several narrow basic dykes, with an easterly strike and vertical dip, cut all other formations. Most are lamprophyres, of either the monchiquite or camptonite type, but one has been identified as a diabase."

Jan 1, 1949

By R. O. Burt

The Tanco pegmatite is located in the Bird River greenstone belt of south-eastern Manitoba approximately 160 km northeast of Winnipeg (Figure 1). The orebody was discovered in 1929 and subsequently attempts were made to exploit it for tin by Jack Nutt Mines Ltd. and later in the middle 1950's by Montgary Oil Ltd., who extensively developed but did not produce from its lithium deposits. In 1966 systematic investigation of the pegmatite as a potential source of tantalum led to the founding of Tantalum Mining Corporation of Canada Ltd. (TANCO), and production of tantalum concentrates from the Bernie Lake mine commenced in 1969. Tanco's currently jointly owned by Hudson Bay Mining and Smelting Co., Cabot Corporation, and the Province of Manitoba.

Jan 1, 1988

By K. [Muthukkumaran

An extensive program of laboratory model tests was undertaken to study the effect of slope on p-y curves under passive loading in dry sand. The paper concerns the method developed in a series of laboratory model tests to experimentally determine p-y curves. Bending moment curves are differentiated by using curve fitting method of cubic polynomial function. The study includes effect of slope angle and relative density on bending moment and non-dimensional p-y curves. The non-dimensional p-y curves for piles on sloping ground under passive load are developed modifying API method by including a Reduction Factor (R) using the experimental results.

Jan 1, 2006

The reformulation of military explosives and solid propellants into commercial explosives offers a unique solution to the problem of disposing of high energy materials with essentially zero environmental impact at a low cost and with a salable product. Studies using the insensitive PBX PBXN-4 have been completed through the pilot plant stage and have been successfully tested as a mining explosive. A number of other military explosives have been examined and their VODs and heats of explosions determined and in some instances tested in 'field" operations.

Jan 1, 1995

By P D. Katsabanis, L Liu

Numerical modelling of fragmentation and throw is used to provide information on practical blast design parameters. The function of airdecking and its practical implications, the importance of the initiation point and aspect ratio of cratering charges and the timing between adjacent blastholes are investigated. Accuracy requirements for detonators are discussed with emphasis placed on the volume and fragmentation of the blasted rock, and compared to experimental results. Practical guidelines which have been based on intuition are examined using the model. Some of the predictions have been tested and correlate well with experimental results, obtained in the laboratory. Findings show that a minimum airdeck length is needed to realize any benefit from the application of airdecking in production blasting while the process can enhance the shock energy provided by non-ideal explosives significantly, bottom initiation of charges is beneficial to fragmentation and the aspect ratio for cratering charges can exceed the traditionally accepted ratio of 6. Regarding timing, in the ease of cratering charges, true simultaneous initiation shows beneficial results for the volume of blasted rock; however the accuracy required for practical detonators is very high. Fragmentation improves after a certain delay time while the optimum can be achieved at a range of delays. Timing affects muckpile shape; however it appears that subtle differences in delay times do not have a significant effect.

Jan 1, 1997

One Hundred and Twelfth Meeting of the Institute, Monday, February 14, to Thursday, February 17, inclusive, 1916 COMMITTEE ON ARRANGEMENTS DAVID H. BROWNE, Chairman. BRADLEY STOUGHTON, Vice-Chairman. LAWRENCE ADDICKS, BURR A. ROBINSON, P. E. BARBOUR, E. M. SHIPP, G. D. BARRON, JOSEPH STRUTHERS, J. V. N. DORR, E. B. STURGIS, J. R. FINLAY 'R. H. VAIL. L. D. HUNTOON, Hotel Accommodations.-The Committee on Arrangements is canvassing a number of hotels in New York City, securing .wherever possible special rates to members and guests for the clays of the meeting. It is possible to secure good accommodations on very reasonable terms in New York City if one knows where to look for them. A list of hotels and rates will be published in the final announcement of the meeting, which will go to the members about the middle of January, in order that those who desire to secure good hotel accommodations at a reasonable mice may have the information.

Jan 1, 1916

By J. E. Zeilinger

This Bureau of Mines report describes the preparation characteristics of the significant coalbeds of Beaver and Lawrence Counties, Pa. Washability analyses were made on seven coalbed samples, none of which were of metallurgical quality as received. Five of the samples could be sufficiently upgraded to produce acceptable products, and the remaining two samples could not be upgraded to metallurgical quality because their sulfur contents could not be lowered to meet the standard. For steam or power generation, one sample was of low sulfur content as received, one sample could be upgraded to low sulfur content, and three samples could be upgraded to medium sulfur content. The original sulfur content of the remaining two samples can be appreciably reduced by removal of the sink 1.58 speci fic gravity material; however, these coals would be classified as medium sulfur coals both before and after removal of the sink material.

Jan 1, 1969

By B. Simser

Noranda?s Brunswick mine is a 10 000 t/d producer of lead-zinc-copper-silver ore that has been in operation since 1964. Mining of this multiple lens deposit is primarily by blasthole stoping techniques between 400 m and 1200 m below surface. The combination of a high overall extraction ratio, an overall steeply dipping tabular shape, and high horizontal stresses (twice the vertical) have elevated the induced stress regime to levels comparable to much deeper operations. Improved mine design, and a better understanding of how the rock mass responds to mining in high-stress environments is essential to improve overall recoveries and maintain safety. Seismic monitoring has proven to be an essential tool at Brunswick, for both short-term safety of workers, and long-term strategic planning. Practical case studies illustrate how seismic data, particularly source parameter information, can be used to measure the rockmass response to mining and improve mining layouts in difficult regions. As the global trend continues toward mining in deeper, higher stress environments (e.g., South African Witswatersrand Basin, Sudbury Basin) and as local extraction and thus ground stresses continue to increase in existing deposits, seismic monitoring will play a critical role in mining safely and economically.

May 1, 2004

By J. W. Downey, R. A. Morris, M. V. Nevitt

An experimental survey has determined the occurrence of Ti2 Ni-type phases in binary and ternary alloys of Ti, Zr, or Hf with first, second, or third long-period transition metals and also in ternary systems in which 0 is the third component. The existence of eleven previously unreported isomorphs is cited and some approximate phase boundaries are given. Lattice parameters are reported for the new phases. The periodic table relationships involved in the occurrence of the phase are discussed. A previous paper' reported the occurrence of a group of Ti2Ni-type phases (structure-type E93) containing Zr in combination with Rh, Ir, and Pt, and Hf in combination with Rh, Pd, Ir, and Pt, and cited evidence to show that all of the Zr phases and the Hf-Pd phase are not binary phases but occur only when 0 is present. More recently one of the present authors found that in the ternary systems of Ti and 0 with Cr, Mn, Fe, Co, and Ni the occurrence of the Ti2Ni-type phase could be correlated qualitatively with valency electron concentration, and that the role of 0 appeared to be that of an electron acceptor.' This paper describes the results of a broader investigation of the occurrence of Ti2Ni-type phases in binary and ternary systems containing Ti, Zr, or Hf. EXPERIMENTAL PROCEDURE Alloys were prepared by arc melting. The purity of the metals Zr, Rh, Hf, Ir, Pd, and Pt was given in the previous paper.' The additional materials used for this work were metals with a minimum purity of 99.9 pct and reagent grade ZrO2, TiO2, Cr2O3, and NiO. Chemical analysis of several alloys in each system indicated good agreement between intended compositions and cast-button compositions. For the heat treatment precautions were taken to avoid oxygen contamination. The specimens were wrapped in Mo foil and sealed in fused quartz tubes at a room temperature pressure of 1 x mm of Hg. These capsules were then annealed in a vacuum furnace at an external pressure of 5 X mm of Hg. Since the major constituent in most of the alloys studied was the brittle Ti2Ni-type phase, Debye-Scherrer patterns with sharp lines could be obtained with powder crushed from the annealed solid samples without being reannealed. Metallographic, X-ray diffraction, and density determination techniques previously described1, 2 were used. RESULTS AND DISCUSSION Zr-Rh-O, Zr-Ir-Oand Zr-Pt-O Systems-Figs. 1 through 3 show the approximate boundaries of the Ti2Ni-type phase fields at the temperatures indicated in the ternary systems Zr-Rh-O, Zr-Ir-O and Zr-Pt-0. In each isothermal section the Ti2Ni-type phase field is labeled E and the unidentified binary phase found in the previous work' is labeled ?. The dotted lines, which are not phase boundaries, correspond to the composition (Zr2 B)1-xOx. In each system the Ti2Ni-type phase field is displaced to the high-Zr side of this composition line. However, the departures from Zr2B stoichiometry for the metal components are not as high as Zr3B, as was inferred from the previous work. Lattice parameters of the Ti2Ni-type phases in the alloys shown as triangular data points in Figs. 1 through 3 are given in Table IA. The probable compositions of the Ti2Ni-type phases have been estimated from the isothermal sections. Although there are a few exceptions that probably result from uncertainties in phase boundary location and from the effect of variation of oxygen content, the generalization can be

Jan 1, 1961

By M. H. Gaskell, D. M. Kehn, G. T. Pyndus

A correlation of the bubble point pressure for black oil systems is developed using the standard physical-chemical equations of soiutions. The correlation is based on 158 experimentally measured bubble point pressures of 137 independent systems and is expressed in terins of the usually measured field pnrameters— flash separation gm-oil ratio, rank oil gravity, total gas gravity, and reservoir temperature. The data were obtained on systems produced in Canada, Western and Mid-Continent01 United States, and South America. The average error (algebraic) in the representation is 3.8 per cent, and the maximum error encountered is 14.7 per cent. INTRODUCTION In the absence of experimentally measured properties of reservoir fluids, it is often necessary for the field engineer to make estimates regarding the fluid properties based on the usually measured producing parameters. To aid in these estimations, various correlations have appeared in the literature in recent years. Among the pertinent properties of interest is the bubble point pressure. A correlation for this parameter has been reported by Standing'. However, this correlation was based essentially on California produced crudes and this limitation was pointed out with its presentation. The correlation presented in this paper utilized data on crude oil systems from Canada, Wes- tern and Mid-Continental United States, and South America. CORRELATION DEVELOPMENT The basic assumption used in this development is the same as employed by Standing', There is a wide variety of ways to combine these parameters; however, in this instance the combination was made on the basis of Henry's law2. Accordingly, the relationship proposed is Although Eq. 2 defines an individual system, it is of limited value since H' is a function of gas-phase composition and the system temperature. It was observed that for the systems where the bubble point was measured at several temperatures that the ratio of the bubble point pressures and the ratio of the corresponding absolute temperatures (R) were practically identical. Thus, for correlation purposes the bubble point pressure may be taken as a direct function of the absolute temperature. This relation is valid only for those systems that are not near the critical point. Accordingly, this correlation will be inadequate for systems in the region of the critical point. The solubility of the various hydrocarbons found in the gas phase increases with the molecular weight. Thus, the saturation pressure should be inversely related to the gas gravity. Applying these principles to Eq. 2 and rearranging terms gives: The variables 02 the left side of Eq. 3 were designated as the "hubble point pressure factor". The number of mols of tank oil per barrel is a function of the "mclecular weight" of the tank oil. Although the tank oil is a complex mixture, it was assumed for the purposes of this correlation that a unique molecular weight could be assigned to a given oil. This was designated as the "effective molecular weight", and was related to the oil gravity, This empirical relationship was developed simultaneously with the correlation by assuming values of M,. and working to obtain a smooth curve for both the correlation and the effective molecular weight. The relationship between the oil gravity and the effective molecular weight used in this correlation is shown in Fig. 1. The effective molecular weight is somewhat higher than the molecular weight of the C fraction. The difference between these values is largest for the low-gravity systems. It is noted that this effective molecular

By E. A. Anderson, P. W. Ramsey, E. J. Boyle

Only a few zinc-rich alloys are in commercial use today, and these depend largely upon solid solution effects for their desirable properties. Typical examples are rolled alloys containing about 1 Per cent of copper, with Or without additions of elements such as magnesium, and die-casting alloys containing about 4 Per cent of aluminum with small amounts of magnesium and sometimes copper." A number of elements are capable of forming alloys with zinc, Which do not enter into solid solution except in limited degree. The Present Paper considers One such system, zinc-titanium, in which alloys having potentially useful properties in the rolled form were found. Zinc-titanium System The zinc-rich portion of the zinc-titanium diagram, as determined by standard methods in this laboratory,3 is shown in Fig. I. The portion of the diagram of significance in the present work extends from 0 to about 0.5 per cent titanium. Gebhardt4 places the eutectic at 0.45 per cent, but the evidence in favor 01 the composition given in Fig. I is considerable. The solid solubility of titanium in zinc is very low indeed and possibly places these alloys in a somewhat different category from the commercial alloys previously mentioned. Alloy Preparation All of the alloys used in this work were prepared with titanium metal of 98.9 per cent purity. In most cases high-purity zinc (99.99 per cent) was used but sufficient work was done later to show that zinc of about high-grade composition would yield approximately equal results. Best practice in alloy manufacture seemed to be to prepare a zinc-titanium hardener by adding about 4 per cent of titanium metal to molten zinc and holding under a boric acid cover, with frequent stirrings, at 750°C, until the titanium had dissolved. The desired titanium content could readily be obtained in the final alloy by adding the calculated amount 01 this hardener. The alloys proved to be quite stable in composition, unless overheated, and, with reasonable temperature control, required no cover or flux to prevent loss of titanium content by oxidatioll, Hot-rollig Tests Three alloys containing, by analysis, 0.05, 0.12, and 0.23 per cent titanium were selected for preliminary study. Slab cross sections a a marked grain refinement* (Fig. 2) in the two alloys of highest titanium content. Cast unalloyed zinc has a columnar grain structure similar to that shown for the alloy of lowest titanium content but without the scatter of small equiaxed grains at the center.

Jan 1, 1944

By P. W. Ramsey, E. J. Boyle, E. A. Anderson

Only a few zinc-rich alloys are in commercial use today, and these depend largely upon solid solution effects for their desirable properties. Typical examples are rolled alloys containing about 1 Per cent of copper, with Or without additions of elements such as magnesium, and die-casting alloys containing about 4 Per cent of aluminum with small amounts of magnesium and sometimes copper." A number of elements are capable of forming alloys with zinc, Which do not enter into solid solution except in limited degree. The Present Paper considers One such system, zinc-titanium, in which alloys having potentially useful properties in the rolled form were found. Zinc-titanium System The zinc-rich portion of the zinc-titanium diagram, as determined by standard methods in this laboratory,3 is shown in Fig. I. The portion of the diagram of significance in the present work extends from 0 to about 0.5 per cent titanium. Gebhardt4 places the eutectic at 0.45 per cent, but the evidence in favor 01 the composition given in Fig. I is considerable. The solid solubility of titanium in zinc is very low indeed and possibly places these alloys in a somewhat different category from the commercial alloys previously mentioned. Alloy Preparation All of the alloys used in this work were prepared with titanium metal of 98.9 per cent purity. In most cases high-purity zinc (99.99 per cent) was used but sufficient work was done later to show that zinc of about high-grade composition would yield approximately equal results. Best practice in alloy manufacture seemed to be to prepare a zinc-titanium hardener by adding about 4 per cent of titanium metal to molten zinc and holding under a boric acid cover, with frequent stirrings, at 750°C, until the titanium had dissolved. The desired titanium content could readily be obtained in the final alloy by adding the calculated amount 01 this hardener. The alloys proved to be quite stable in composition, unless overheated, and, with reasonable temperature control, required no cover or flux to prevent loss of titanium content by oxidatioll, Hot-rollig Tests Three alloys containing, by analysis, 0.05, 0.12, and 0.23 per cent titanium were selected for preliminary study. Slab cross sections a a marked grain refinement* (Fig. 2) in the two alloys of highest titanium content. Cast unalloyed zinc has a columnar grain structure similar to that shown for the alloy of lowest titanium content but without the scatter of small equiaxed grains at the center.

Jan 1, 1944

By Jing Zhou

2-hydroxy-3-naphthoy hydroxamic acid code name F203 is a good collector of cassiterite, 1-hydroxy-2-naphthoy hydroxamic acid code name ZJ-3. F203 and ZJ-3 are similar series of isomers. They have similar naphthye, and similar series of functional OH and ?CONHOH, but the seat of OH and ?CONHOH group are different, on the F203 is 2.3; on the ZJ-3 is 1.2, ortho position too. According to Isomeric principle ZJ-3 is a good collector of cassiterite slime too. Using ZJ-3 as collector flotation -10µm occupies 90%, grade 1.16% Sn cassiterite slime of Da Chang Chehe concentration plant, pass one coursing flotation, two cleaning and one scarenging flotation, and obtains grand 18.26% Sn, recovery 92.68% cassiterite concentrate. The result proves the Isomeric principle of flotation reagents is correct again. This principle may supply to synthetize new flotation reagents reference. Keywords: F2O3, ZJ-3, cassiterite flotation, Isomeric principle, Isomeric principle of flotation reagents

Sep 1, 2012

By Parker RJ, Swindells CF

The authors have used the geotechnical study for design of the South Wall of Mt. Newman Mining's Mt. Whaleback Mine to illustrate how geotechnical studies can be economically justified. This is achieved by relating the savings resulting from increased ore recovery and prevention of failure to the cost of the study. An outline of the geotechnical study is provided in the paper, including a brief description of the innovative methods used to investigate geological structure of the mine and descriptions of the methods of slope reinforcement adopted.

Jan 1, 1986