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By C. R. Kuzell

Although furnaces constructed of refractory brick have been operated for many decades, there has always been an unfulfilled desire by the operators for a less arduous and more satisfactory method of patching weak spots and burned-out zones in order to postpone and to effectively extend the termination of a furnace campaign. Not only has this desire frequently arisen when small spots have approached incipient failure while the furnace structure as a whole was still in good condition, but also when larger areas showed signs of needing replacement. The available methods have been arduous, sometimes dangerous, inefficient with respect to the life of new refractory material used, and nearly always have necessitated interruption of the continuity of the furnace operations and therefore reduction in furnace production during the period of time required for the repair work. Most of these older methods have involved the replacement of masonry by refractory shapes in the weakened areas. Many attempts have been made to develop a method of patching the burned-out areas by spraying granular refractory material upon old surfaces. While some success has been attained in attempts to renew the grooved, corroded side walls and fettling, and the edges of hearths, there have been no known successful applications of the spraying method in patching the underside of arches of operating furnaces. The method developed recently at the Clarkdale smelter of the United Verde Branch of Phelps Dodge Corporation, at Clarkdale, Aria., and described in this paper, has been found to be not only convenient and successful with respect to patching vertical or inclined surfaces, but has met with a marked degree of success in patching the parts of furnace arches that are exposed to flame, the successful result being obtained without interruption or interference with the continuity of furnace operations. It may be described as a method of renewing the interior refractory surfaces of operating furnaces by pneumatic spraying of an aqueous suspension of finely divided. particles of refractory material. It has been used

Jan 1, 1944

Many of those who attended the meeting at Chicago spent the first part of the following week in Pittsburgh, when the Experiment Station of the Bureau of Mines was dedicated and the fourth annual First Aid and Mine Rescue Contests were, held. The Bureau buildings were open for inspection during the three days, Monday, Tuesday, and Wednesday. The dedicatory ceremonies were held in the Bureau of Mines main building, Monday morning, Sept. 29, Mr. T. J. Gillespie, representing the Pittsburgh Chamber of Commerce, presiding. In his address of welcome, Hon. E. V. Babcock, Mayor of Pittsburgh, said: "The reclamation work already done stands out conspicuously beneficial to industry and populace alike all over the United States. It has demonstrated methods of preservation of life and reclaiming of injured persons which are new and greatly beneficial to modern civiliza-tion. The establishment of this institution in Pittsburgh was greatly desired, and now it is here it is greatly appreciated." The response was given by First-Assistant Secretary of the Interior Vogelsang, who represented Secretary Franklin K. Lane. He said that the Bureau of Mines did more during the war for the triumph of American arms than any other institution.

Jan 11, 1919

By C. R. Kuzell

ALTHOUGH furnaces constructed of refractory brick have been oper-ated for many decades, there has always been an unfulfilled desire by the operators for a less arduous and more satisfactory method of patching weak spots and burned-out zones in order to postpone and to effectively extend the termination of a furnace campaign. Not only has this desire frequently arisen when small spots have approached incipient failure while the furnace structure as a whole was still in good condition, but also when larger areas showed signs of needing replacement. The availa-ble methods have been arduous, sometimes dangerous, inefficient with respect to the life of new refractory material used, and nearly always have necessitated interruption of the continuity of the furnace operations and therefore reduction in furnace production during the period of time required for the repair work. Most of these older methods have involved the replacement of masonry by refractory shapes in the weakened areas. Many attempts have been made to develop a method of patching the burned-out areas by spraying granular refractory material upon old surfaces. While some success has been attained in attempts to renew the grooved, corroded side walls and fettling, and the edges of hearths, there have been no known successful applications of the spraying method in patching the underside of arches of operating furnaces. The method developed recently at the Clarkdale smelter of the United Verde Branch of Phelps Dodge Corporation, at Clarkdale, Ariz., and described in this paper, has been found to be not only convenient and successful with respect to patching vertical or inclined surfaces, but has met with a marked degree of success in patching the parts of furnace arches that are exposed to flame, the successful result being obtained with-out interruption or interference with the continuity of furnace operations. ? It may be described as a method of renewing the interior refractory sur-faces of operating furnaces by pneumatic spraying of an aqueous suspen-sion of finely divided particles of refractory material. It has been used

Jan 1, 1939

By Alan Probert

IN his inaugural address in 1949, President Truman made a policy declaration which launched the foreign technical assistance program known to the world as Point Four. Congress passed Public Law 535 defining the scope of the program and holding activities to certain limitations. It also provided $34.5 million for the first fiscal year. The Technical Cooperation Administration was established within the Department of State to coordinate and direct a program to include "economic, engineering, medical, educational, agricultural, fishery, mineral and fiscal surveys, demonstration, training and similar projects." The mineral programs of Point Four have been staffed and managed by two agencies of the Department of Interior, the Geological Survey and the Bureau of Mines. The Geological Survey is concerned primarily with water-supply problems, the discovery of mineral deposits, and the determination of habit, shape, and grade of mineral deposits. The Bureau of Mines is concerned with determining the commercial potentialities of mineral deposits, mineral technology, and the production and distribution of mineral commodities. Mineral projects comprised only 1 pet of the first year's budget. In spite of the relatively insignificant expenditure compared to those for food, agriculture, and health, a commendable record has been achieved.

Jan 1, 1952

By John Norton

THE tremendous increase in the use of metals that have been prepared by the various cold-working processes during recent years has greatly stimulated the investigation of problems concerned with the fundamental nature of these processes. It has been observed in practice that different methods of bringing about the same dimension changes in a sample result in a rather wide range of properties. Cold working reduces the ductility of a metal, or what is perhaps more nearly correct, its "working capacity," and naturally the manufacturer wishes to produce an article that has as large a working capacity as possible, and to produce it with the smallest number of operations, It has also been known for some time that cold deformation produces a parallel alignment of the crystal grains of a metal, and that the type of this preferred orientation depends to some extent at least upon particular processes employed in the deformation. The present investigation has for its purpose the study of the relations between the various factors of a cold-working process and the preferred orientation of the metal crystals resulting from this deformation. The work is chiefly confined to a study of cold-drawn seamless tubing.

Jan 1, 1932

By Khosrow Bakhtar

A series of nineteen shear tests were performed on fractures 1 m2 in area, generated in blocks of sandstone, granite, tuff, hydro- stone and concrete. The tests were conducted under quasi-static and dynamic loading conditions. A vertical stress assisted fracturing technique was developed to create the fractures through the large test blocks. Prior to testing, the fractured surface of each block was characterized using the Barton JRC-JCS concept. The results of characterization were used to generate the peak strength envelope for each fractured surface. Attempts were made to model the stress path based on the classical transformation equations which assumes a theoretical plane, elastic isotropic properties, and therefore no slip. However, this approach gave rise to a stress path passing above the strength envelope which is clearly unacceptable. The results of the experimental investigations indicated that actual stress path is affected by the dilatancy due to fracture roughness, as well as by the side friction imposed by the boundary conditions. By introducing the corrections due to the dilation and boundary conditions into the stress transformation equation, the fully corrected stress paths for predicting the strength of fractured blocks were obtained.

Jan 1, 1984

MINING ASSOCIATION OF UNIVERSITY OF CALIFORNIA At a meeting of the Mining Association of the University of California, held May 22, .the .following officers were elected for the fall, semester: President, Sam Grinsfelder; vice-president, Marcus. Peterson; secretary, Ferdinand Trescher; treasurer, Carlton Hulin. F. G. TRESCHER, Secretary.

Jan 8, 1919

By E. Gybbon Spilsbury

From time to time, for the last quarter of a century, considerable attention has been called to the gold deposits of North Carolina and Georgia, and much capital has been expended in their development; but the existence of large areas of gold-bearing rocks in the State

Jan 1, 1884

By Samuel M. Cassidy

The exact date of man's first use of coal is lost in antiquity. The discovery that certain black rock would burn was undoubtedly accidental and probably occurred independently and many times in the world over thousands of years. It is quite likely that these independent discoveries were made when primitive man chanced to build camp fires on exposed ledges of a black stone, then was amazed when it caught fire. The Chinese recorded the use of coal 1100 years before the Christian Era. And, from the Bible we learn that King Solomon was familiar with coal in what is now Syria. In Wales, there is evidence that the Bronze Age people used coal for funeral pyres, and it is known that the Romans used this fuel. There are other ancient references. So the knowledge that coal would burn, and even some uses of that knowledge, goes back for thousands of years. However, practical and consistent use of coal seems to date to England in the Middle Ages. COAL IN AMERICA In the Americas, there is evidence here and there of a slight use by the Indians. However, the first recorded discovery of coal, in what is now the U.S., was by French explorers, who reported a "cole mine" on the Illinois River in 1679. Following this, other discoveries were made by French and British explorers, but the first recorded actual usage was in Virginia in 1702, where a French settler was granted permission to use coal for his forge. Earliest recorded commercial mining was in 1750, from the James River coalfield near Richmond, Va., a deposit now abandoned. Besides local consumption from this field, shipments were made to Philadelphia, New Pork, and Boston. During the Revolution this coal was of importance in the manufacture of shot and shell; so important, in fact, that the British sent an expedition in 1781 to destroy the iron works and

Jan 1, 1973

By L. B. Slichter

It has been estimated that rock exposures in most mining districts aggregate less than 1 per cent. of the total surface area.1 Conclusions concerning the hidden 99 per cent. necessarily have been based on knowledge of only a small fraction of the surface, and from this limited information the geologist has been obliged to deduce the approximate and general nature of the underlying formations. In the search for ore it is necessary to supplement this general picture with greater detail. Fairly accurate knowledge of relatively small zones is required. This knowledge is carefully sought in many different ways—detailed interpretations of geological history, the tracing of float, the use of test pits, of trenching, of drilling, and of other methods. Practical ingenuity, scientific brilliance, great perseverance and patience, and the expenditure of large sums of money have all been a part of this search. The problem of exploring beneath cover with economy, and of obtaining essential information which this cover hides, is obviously a difficult one. It is also a very important one, for geologist's inform us that already the story of the 1 per cent. exposed outcrops has been largely read.V here remains the nearly virgin field comprised in the hidden 99 per cent.: and the importance of this zone is bound to increase continually. In recent years, the problems connected with the exploration of this "99 per cent. zone" have attracted a constantly enlarging group of investigators and at present greater efforts than ever before are being made to resolve them. This work, in it's various special aspects, has enlisted, beside geologists, the cooperative efforts of chemists, physicists, and mathematicians. The progress made in this development should be kept before those directing explorations in order that due advantage may be taken of a changing situation. My subject concerns certain aspects of one of the older physical methods of exploration, the magnetic method. This method is familiar in principle to most of us, arid because of its age., is especially suitable for

Jan 1, 1929

By Paul A. Bailly

2.1-1. The Exploration Function in the Mineral Industry. With regard to a new mine, exploration can be technologically defined as all the activities and evaluations necessary before an intelligent decision can be made establishing size, initial flowsheet, and annual output of the new extractive operation based on a certain mineral deposit. The activities that follow such a decision are called first development, then operation (90). Thus, in the U.S.A., exploration may continue in the technological sense after a mineral property has entered the "development stage" as defined for tax purposes. Regulations under Sections 1.615.1 and 1.616.1 of the U.S. Internal Revenue Code state that the "development stage" has been reached when "deposits of ore or other minerals are shown to exist in sufficient quantity and quality to reasonably justify commercial exploitation by the taxpayer" (95). There are, of course, many instances where additional later exploration discloses additional reserves which justify a plant much larger, more efficient and more profitable than the minimum feasible commercial operation. After a surface mine is put into operation, additional search generally will increase the reserves and thus warrant expansion of the rate of output and/or extend the life of the operation. The methods and techniques in such search are similar to those used in predevelopment exploration. This activity has produced a major part of new reserves for all mineral commodities but is not considered as exploration in the context of this chapter. The objective of exploration is, briefly stated, to find and acquire a maximum number of new economic mineral deposits with a minimum cost and in minimum time. The search must be so organized as to maximize the overall probability of discovering commercial mineral concentrations within a minimum time with the funds available. As shown by Celasun (27) these statements are neither adequate nor complete from a pragmatic point of view. Each actual exploration venture must define its objectives in terms of a minimum rate of return on investment for any deposit found

Jan 1, 1968

By J. L. Gregg, C. W. Kuttner

ReceNtly there has been considerable interest in the production and use of extra hard alloys composed primarily of tungsten and carbon. Dr. Hoyt's recent paper1 gives a good description of these alloys and describes their performance when used as tools. There are a number of these alloys on the market sold under various trade names, and it is the purpose of this paper to describe the results of an investigation of the structure of five of these alloys by means of microscopic and X-ray methods. The samples studied were in the form of small tools or wiredrawing dies, which were either purchased or supplied as samples. They were in some cases not supplied by the original makers but were furnished by the agents in this country, and we wish to call attention to the fact that they may not be truly representative of the materials supplied under the various trade names No performance data are given and no inference as to the inferiority of one alloy as against any other is made. K. Schröter2 recently described methods for polishing alloys of this type for microscopic examination and has presented photomicrographs of several alloys. However, he did not identify their constituents or describe methods for their identification. Constituents and Their Identification As far back as 1915 attempts were made to utilize tungsten carbides commercially, but the great brittleness of these carbides made these first attempts unsuccessful. Later, successful dies were made by sintering the powdered carbides with small amounts of iron, nickel, or cobalt. Due to the high melting points of the tungsten carbides (2600" to 2800" C.), it is difficult to melt the carbides without volatilizing almost quantitatively the added element of the iron group. Inasmuch as the added metal does not exceed 20 per cent. and is usually present in much smaller amounts, some understanding of the tungsten-carbon equilibrium dia-

Jan 1, 1929

By C. W. Kuttner, J. L. Gregg

ReceNtly there has been considerable interest in the production and use of extra hard alloys composed primarily of tungsten and carbon. Dr. Hoyt's recent paper1 gives a good description of these alloys and describes their performance when used as tools. There are a number of these alloys on the market sold under various trade names, and it is the purpose of this paper to describe the results of an investigation of the structure of five of these alloys by means of microscopic and X-ray methods. The samples studied were in the form of small tools or wiredrawing dies, which were either purchased or supplied as samples. They were in some cases not supplied by the original makers but were furnished by the agents in this country, and we wish to call attention to the fact that they may not be truly representative of the materials supplied under the various trade names No performance data are given and no inference as to the inferiority of one alloy as against any other is made. K. Schröter2 recently described methods for polishing alloys of this type for microscopic examination and has presented photomicrographs of several alloys. However, he did not identify their constituents or describe methods for their identification. Constituents and Their Identification As far back as 1915 attempts were made to utilize tungsten carbides commercially, but the great brittleness of these carbides made these first attempts unsuccessful. Later, successful dies were made by sintering the powdered carbides with small amounts of iron, nickel, or cobalt. Due to the high melting points of the tungsten carbides (2600" to 2800" C.), it is difficult to melt the carbides without volatilizing almost quantitatively the added element of the iron group. Inasmuch as the added metal does not exceed 20 per cent. and is usually present in much smaller amounts, some understanding of the tungsten-carbon equilibrium dia-

Jan 1, 1929

By Burt C. Mariacher

The Minerals Beneficiation Division meets each year at the Annual Meeting of AIME. All members are invited and encouraged to attend. For the information of those who did not attend the meeting in Denver last February, this column presents a summary of the reports given and topics discussed. Technical Committee Coordination Consolidation of technical programs having common interest to MBD and the Extractive Metallurgy Division is proving a considerable success, both on the technical committee level-through the efforts of the MBD-EMD Coordinating Committee-and in special symposia. MBD Chairman, R. S. Shoemaker, noted that J. D. Prater will be serving as Chairman of both the MBD Chemical Processing Committee and the EMD Hydrometallurgy Committee for 1970-71. R. P. Ehrlich commented on the cooperative effort of both divisions in organizing the Copper Metallurgy Symposium held at the Denver Meeting. This effort, he said, was important to the success of the Symposium. H. R. Spedden discussed inter-Division coordination activities on the SME level. The forthcoming MBD-M&E-EMD Joint Lead-Zinc Symposium is yet another example of progress in this direction.

Jan 1, 1970

As is known to representatives on Engineering Council, the Patents Committee of Council has collaborated with the similar committee of National Research Council in developing a scheme for the improvement of the method of dealing with patents in this country. The staff of the Patent Office is itself actively engaged in this effort. Out of the report prepared by the National Research Council, and approved and adopted by Engineering Council as the report also of its Patents Committee, remedial legislation has taken form. Three hills have been introduced, known as H.R. 5011, a bill to make the Patent Office independent of the Department of the Interior or any other department, and to simplify the procedure of the Courts with reference to assessment of damages or profits for infringement of patents; H.R. 5012, a bill to establish a single Court of Patent Appeals; and H.R. 7010, a bill to increase the force and salaries in the Patent Office. Chairman Charles A. Terry, of the Patents Committee, requests that representatives of Engineering Council write to their congressmen, urging the passage of these hills and so far as convenient, request their friends to do likewise.

Jan 9, 1919

By T. V. Subrahmanyam, A. P. Rao

The adsorption behavior of chalcopyrite has been studied at different xanthate concentrations and flow rates in a column apparatus with potassium ethyl xanthate as the collector. Based upon the experiment results an equation of the type: 1/F = K3 + m3C + k2/t.Cm2.fm1 is proposed to account for the experimental data. Among copper minerals an early study on chalcocite by Gaudin and Schuman (Taggart, 1951) is well known for its research on the kinetics of the reaction by conventional method of mass balance between the products of reaction and xanthate consumed. The results were interpreted by the concept of ion exchange adsorption. Szeglowski (1977) conducted measurements on the adsorption of potassium ethyl xanthate on copper polarized to various potentials, the adsorption being measured by radio-tracer techniques. The adsorption in the range -1800 to 700 mv was found to be a reversible physical adsorption. The potential range in which the primary electrode process could lead to surface coverage with a minimum number of product layers was evaluated. The adsorption density of xanthate on sulfide surface was found to be related to the concentration of xanthate in solution and concentration of depressants as: [ ]

Jan 1, 1983

THE first award of the James Douglas gold medal for achievement in non-ferrous metallurgy was made to Frederick Laist, of the Anaconda Copper Mining Co., and the presentation ceremony was a feature of the annual banquet of the Institute at the Waldorf, on Feb. 21. Frederick Laist was born in Cincinnati, Ohio, Oct. 30, 1878. In his early youth his parents moved to California where, in 1901, Mr. Laist graduated from the University of California, in the course of chemical en-gineering. For one year after graduation he was an in-structor in chemistry at the University of Utah. Fol-lowing this he was employed as a chemist in the lab-oratory of the Washoe Reduction Works of the Anaconda Copper Mining Co., where in successive stages he has occupied the position of chief chemist, blast-furnace superintend-ent, assistant superintend-ent of the entire plant, superintendent, and finally manager of the Anaconda company's reduction plants in Montana, which position he now holds. Mr. Laist, in his labora-tory work, manifested great interest in the hydrometal-lurgy of copper and zinc. As chief chemist at Anaconda, he brought the laboratory to a high degree of efficiency.

Jan 3, 1923

By A. Eilers

In a former paper on Western Smelting Works, I mentioned the great difficulty of obtaining accurate information in regard to the economy of the processes in practice; and to-day, although nearly two years have elapsed since my former paper was written, I am sorry to say that very little improvement has taken place in the keeping of accounts, and in the direction of a more systematic management in the majority of these works. But I am quite certain that by this time even the most sanguine furnace managers must have become convinced, from the experience of the last year, that somewhere in their processes there are enormous losses. Rates for the purchase of ores in 1873 were not as high as they were in former years in certain parts of the country ; labor was no 'higher than formerly; the demand for unparted lead was good throughout the year, with the only exception of the time of the panic, in the fall of 1873; yet there are, of between 40 and 50 works, not more than two or three in Utah and Nevada to-day, that have paid a reasonable interest on the capital invested.

By A. Filers

IN a former paper on Western Smelting Works, I mentioned the great difficulty of obtaining accurate information in regard to the economy of the processes in practice ; and to-day, although nearly two years have elapsed since my former paper was written, I am sorry to say that very little improvement has taken place in the keeping of accounts, and in the direction of a more systematic management in the majority of these works. But I am quite certain that by this time even the most sanguine furnace managers must have become convinced, from the experience of the last year, that somewhere in their processes there are enormous losses. Rates for the purchase of ores in 1873 were not as high as they were in former years in certain parts of the country ; labor was no higher than formerly ; the demand for unparted lead was good throughout the year, with the only exception of the time of the panic, in the fall of 1873; yet there are, of between 40 and 50 works, not more than two or three in Utah and Nevada to-day, that have paid a reasonable interest on the capital invested.

Jan 1, 1875

By Om P. Garg

During the period between 1970 and 1974 the Iron Ore Company of Canada had embarked on a detailed program to evaluate all aspects of mine design work for its open pit mines around Schefferville, located both in Quebec and Labrador, Newfoundland, Canada. One of the main conclusions was that the majority of the slope angles for the ultimate pit walls could be steeped. During the period 1975 and 1976,five (5) open pit iron ore mines were redesigned using the steeper slope angles up to 55 degrees. Initially these pits were designed at slope angles varying between 37 degrees and 45 degrees due to the generally fractured and leached nature of rocks in the area. During the active mining phase between 1976 and 1979, the stability of the steeper ultimate pit walls was monitored. The mining of ore was successfully completed in 1978 and 1979 in three pits. This of course, resulted in a significant savings due to a reduction in the quantity of waste that had to be removed. The successful pit slope redesign project was a co-operative effort between the Federal Government, Universities and the Iron Ore Company of Canada.

Jan 1, 1983