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By Vsevolod Krivobok

IT is generally recognized that "low temperatures" have a definite effect on the properties of metals and alloys. Furthermore, it is also generally understood that the effect is decidedly adverse. The possibility that the same low-temperature treatment might be employed for the purpose of improving certain properties of the .alloys has received less attention until recently, and the experimental and theoretical knowledge consequently is meager. The effect of low temperatures may be studied in two ways: by studying such properties as tensile strength, hardness, impact resistance, etc., at low temperature, and by studying the properties of alloys at room temperature after these alloys have been subjected to a low-temperature treatment. Even in the latter case, certain properties will differ materially from the same properties obtained on identical material but without cold treatment. In other words, subjecting alloys to cold treatment results in an irreversible change in mechanical properties. Changes of this character are usually indications of the appearance of a new phase or phases, and would be likely to occur in alloys which, either by virtue of their composition or by heat treatment, are retained at room temperature in a metastable condition. Consequently, studies of the effect of low temperatures logically should be conducted from the physicochemical point of view, since the results of such studies not only would furnish metallurgists with interesting theoretical data but would clearly indicate the classes of alloys that would hold promise of improvement, and, possibly, of new applications. As the present investigation deals with chromium and chromium-nickel alloys of iron of the stainless variety, it has been thought desirable to present the data concerning low-temperature properties of these alloys, available from the most recent and most comprehensive work of H: S. Russell.' A summary, of these data is given in Table 1. The data are confined to a limited number of alloys of the type dealt with in the present

Jan 1, 1931

By Richard R. Klimpel

The role of dispersion is described in the wet grinding of ores using tumbling media mills and the flotation of coal, sulfide, and non-sulfide ores. Emphasis is placed on characterizing the effects of dispersion in laboratory tests using engineering models which provide information useful for the improvement and control of existing plant operations. Significant economic gains in the above named operations have been realized using these models as guides for full- scale plant testing.

Jan 1, 1980

By R. M. Raymond

THE Mining Section of The National Safety Council recently sent out a questionnaire to operators, regarding the class of rope used, specifications required or obtained, factors of safety observed, methods of fastening ropes, lubrication, inspection, and points observed when rope is to be discarded. The answers received from this questionnaire, largely from metal mines, give interesting information, from which recommendations for safety practice on hoisting ropes are drawn. DEPTH OF MINE The depth in the majority of cases noted is from 1000 ft. to 1500 ft. (304 to 457 m.) and records come from a number hoisting from depths of 2000 to 3000 ft. Hoisting is generally done in balance, with a few companies using counterweights. Seldom, more than two shifts are occupied in hoisting. A number of large operators limit the shift for engineers to 6 hr. A few of the larger operators have separate hoists for men and supplies, with a higher class rope for men. The range of loads varies from 7 to 17 tons and greater in a few cases, with a balanced weight of 4 to 7 tons.

Jan 2, 1922

By Ernest R. Lilley

While American scientific literature contains much information upon geologic conditions controlling the production of oil in Rumania, copper in Chile, and other fuel and metallic resources in many foreign countries, it is singularly lacking in data about the nonmetallics outside of the United States. Thus, though the United States is the outstanding market for European high-quality refined kaolin, and for the chinaware, porcelain, and other products of the European ceramics industries, American literature contains only the briefest references to the deposits from which the raw kaolin utilized is obtained. To the writer, to whom has come in the past year the opportunity of visiting a number of these deposits personally, they have proved of extreme interest both commercially and geologically. It is the latter phase that is discussed in this paper. The older and now largely crystalline rock areas of France, Germany, and other parts of western Europe contain numerous pegmatite dikes of which the upper portions have been subjected to surface weathering and kaolinization in much the same way as those of the eastern portion of the United States. Like the latter, the European pegmatite kaolins have long been known for their freedom from iron and other impurities offensive to the china and porcelain manufacturer. Unfortunately, they are also, like the American deposits, individually of small size and noted for their high costs of production. Deposits of sedimentary clay similar in many respects to the high-quality sedimentary kaolins of Georgia and South Carolina are known and worked, notably in southern Germany and in the Newton Abbott district of Devon and Dorset in England. In general, their relationship to the parent rock from which they were derived is more evident than in the United States and the individual deposits are of smaller areal extent and less regular in outline. While these deposits are of considerable economic importance they did not, because of their similarity to deposits in America, attract and hold the interest of the writer to the extent that several other types of deposits did. It is to the latter, which are so different from the kaolin

Jan 1, 1932

In one of the largest dredging projects of its kind, Lake Asbestos of Quebec Ltd. is stripping overlying mud and sand from the bed of a lake to reach asbestos orebodies 70 to 200 ft below surface. Black Lake, about two miles long by half a mile wide, was almost overlooked in the search for asbestos in Quebec's ore-rich eastern townships-a search that has been underway there ever since the first asbestos was mined in 1877. Not until 1948 was the Black Lake mineral discovered. Four years later careful exploration was carried out by American Smelting & Refining Co., parent firm of Lake Asbestos. The search involved more than 75,000 ft of diamond drilling and about 5000 ft of underground work. ASARCO, in its first asbestos mining project, decided to proceed with a dredging and draining program to prepare for open pit mining.

Oct 1, 1956

By G. D. Tranter

The importance of ladle and teeming practice and its relationship to the yield and quality of the product has focused considerable attention on this phase of open-hearth operation. Inherently bad steel cannot be perfected by manipulation during teeming, but through the proper handling of "off heats" serious losses, which in many cases arise, can be greatly minimized. Conversely, good steel can be ruined as a result of poor workmanship in the pit, and rendered unsuitable for application to orders where exacting surface and physical requirements are essential. Sufficient evidence has been secured to warrant careful investigation of pit operations when an abnormal number of basic defects develop in the semifinished product or are found on the inspection table. This paper is written from the standpoint of the problems involved in making satisfactory ingots for sheet rolling. Furthermore, since rimming steel is almost universally used for manufacture of sheet, the data presented herein refer particularly to that type of steel. Going back some 30 years in open-hearth history, the word "pit" properly described the hole into which the ladle was lowered to receive the metal tapped from the furnace. The working space was necessarily limited, and the disposal of slag and metal overflowing the ladle or lost because of breakouts presented a serious problem. The equipment, of course, was rather crude in the light of present-day development. Often no ladle stands were provided, the ladle being hung on the crane beneath the runner. When delayed taps occurred, the ladle was often held in position for many hours, thus tying up pit operations and causing delays to adjacent furnaces. Because of crowded conditions, slag thimbles were not used and a network of cast-steel triangles and old tapping bars, placed before the heat was tapped, was the means for removing slag from the hole. Furnaces of different capacities were used

Jan 1, 1935

By G. D. Tranter

The importance of ladle and teeming practice and its relationship to the yield and quality of the product has focused considerable attention on this phase of open-hearth operation. Inherently bad steel cannot be perfected by manipulation during teeming, but through the proper handling of "off heats" serious losses, which in many cases arise, can be greatly minimized. Conversely, good steel can be ruined as a result of poor workmanship in the pit, and rendered unsuitable for application to orders where exacting surface and physical requirements are essential. Sufficient evidence has been secured to warrant careful investigation of pit operations when an abnormal number of basic defects develop in the semifinished product or are found on the inspection table. This paper is written from the standpoint of the problems involved in making satisfactory ingots for sheet rolling. Furthermore, since rimming steel is almost universally used for manufacture of sheet, the data presented herein refer particularly to that type of steel. Going back some 30 years in open-hearth history, the word "pit" properly described the hole into which the ladle was lowered to receive the metal tapped from the furnace. The working space was necessarily limited, and the disposal of slag and metal overflowing the ladle or lost because of breakouts presented a serious problem. The equipment, of course, was rather crude in the light of present-day development. Often no ladle stands were provided, the ladle being hung on the crane beneath the runner. When delayed taps occurred, the ladle was often held in position for many hours, thus tying up pit operations and causing delays to adjacent furnaces. Because of crowded conditions, slag thimbles were not used and a network of cast-steel triangles and old tapping bars, placed before the heat was tapped, was the means for removing slag from the hole. Furnaces of different capacities were used

Jan 1, 1935

By Thomas J. Pike, Keith G. Kirk, Mark F. Weider, Lawrence E. Welborn

As part of the mine permitting process as delegated by the Surface Mining Reclamation and Control Act of 1977 the regulatory authority must assess the probable hydrologic consequences and cumulative hydrologic impacts of surf ace mining. The U.S. Office of Surface Mining (OSM), in conjunction with Energy & Minerals Technology Assessment and ENCORE Systems Inc., has developed a user friendly groundwater model that is capable of predicting the effects of surface mining on groundwater quality and quantity. The model is a variation of the Prickett-Lonnquist model which has been modified to be specifically applicable to surface mine applications. This model is presently being used by OSM, the states, and industry to determine mining impacts on groundwater resources. The model is designed for use by the hydrologist with minimal computer training. The model accounts for multiple pumping wells, injection wells, multiple mine pits, and mine pit movement through time. This paper presents an example of how the model may be used in permit application review and how the model can be used by industry to simplify permit preparation.

Jan 1, 1983

Secretary Membership Committee Increase of Membership Papers and Publications Committee Library Committee Treasurer Report of the Secretary TO THE BOARDOF DIRECTORASN D THE MEMBEROS F THE AMERICANIN STITUTE OF MINING AND METALLURGICAENL GINEERS GENTLEME:N As will be shown by the special reports of the Finance, Membership, Library, Papers and Publications, Increase of Membership, and other standing Committees, together with that of the Treasurer, the year 1927 was one in which the Institute made very satisfactory progress in a number of directions. In total numbers the membership is no larger but in revenue from dues there has been a marked increase. This has been due to the promotion to full membership of Junior Associates of earlier years, to the larger proportion that come in originally as members rather than juniors, and to the keener interest in the work of the Institute reflected in prompter payment of dues. The latter is important, since experience shows that of those who fall behind a large number must ultimately be dropped for non-payment. Conditions in the mining industries have been healthy though not booming. It has been much easier for members to find employment and meet their financial obligations but there has not been that flow of young men into mining, and hence in part into the Institute, that characterized certain earlier years. Rather the tendency toward centralization and larger industrial units has restricted the number, though not the scope, of opportunities for technical men in the mineral industries. The Institute is constantly receiving resignations from members crowded out of mining into other lines of activity. On the other hand, those who remain in mining and metallurgy have a greatly increased necessity for i,dormation and contacts with technology. A few years ago many superintendents and most foremen were non-technical men. Today the reverse rule obtains and shift bosses and men who occupy even lower positions in industrial units are called upon to know and to apply such an amount of technical knowledge that graduate engineers are the rule rather than the exception. The curious situation has obtained that with a much smaller enrolment of students in the schools of mining and metallurgy there has been at times an actual shortage of young engineers for beginners' jobs. The young men retort that the conditions of employment and pay offered in mining are not equal to those in other lines and, while it is undoubtedly true that the young engineer beginning in mining is able to start under conditions markedly better as to pay, living, and responsibility than did the men who are now leaders, they are required to know much more and have usually spent more in time and money to qualify for their jobs. The whole matter is one which warrants much more attention than has been given to it. For the Institute it is important since the young men

Jan 1, 1928

By Warren Blauvelt

IN VIEW of the enormous wastes of natural resources, of labor and of capital, due primarily to the economic environment, established by legislation, the general neglect of this phase of the problem of the elimination of waste is difficult to understand. In such a study, the engineering method of attacking a problem should be employed. The engineer does not try to solve his problem by disregarding natural laws, but by utilizing them. The successful engineer establishes an environ-ment in which forces, acting in harmony with natural laws upon an object or objects, will produce the desired results. The engineer who notices that the water level in a vessel, into which a gallon of water per minute is flowing, is two feet higher than the level in an adjacent vessel, connected therewith by a 6-in. pipe, does not assume that the law of gravity has ceased to work, or that water no longer seeks its level; he examines the connecting pipe for obstacles which prevent the free flow of water. Some editors, many reformers and most politicians tell us that the law of supply and demand no longer works; hence governmental control of commerce is necessary. Governmental control may temporarily-that is, until trial proves its futility- "insure domestic tranquility" and "promote the general welfare;" but it cannot "secure the blessings of liberty" which it cur-tails, nor can it "establish justice" which it violates.

Jan 9, 1922

By Robert E. Snow, Douglas J. Cosler

The application and development of computer models for simulation of transient ground water inflow to underground mines can assist in mine planning and operation as well as environmental impact assessment. Applications include planning for water handling, treatment, and disposal operations based on predicted mine inflow rates, determination of mining impacts on ground water movement and potentiometric surfaces in neighboring aquifers, evaluation of methods for minimizing ground water inflow, and determination of ground water inflow quality. The potential ground water inflow components to a mine consist of direct inflow from an adjacent aquifer and infiltration through intervening geologic formations. The rates of inflow are controlled by the geologic conditions, the potentiometric surface of the aquifer, and the hydrogeologic characteristics of the water-bearing and confining formations. The capabilities and potential use of a computer model for simulation of mine inflow are illustrated through an example problem.

Jan 1, 1983

By Edward Wisser

The environment of an ore body is taken to mean not only its physical surroundings but every factor, passive or active, that conditioned the ore shoot, saving only the original composition of the solutions that formed the shoot. Collection of data related to the shape and characteristics of veins should be followed by correlation of the data and the formulation of generalizations regarding ore formation. The nature of the criteria used in arriving at these generalizations is discussed. Certain of the criteria, when used with an understanding of their underlying causes, become "ore-guides." In the course of his study the geologist must not confine himself to the immediate surroundings of the veins, but should attempt to work out the geologic history of events culminating in the crucial epoch for any mining district, the period of mineralization. The work may involve study of features far removed from the veins and related to them only indirectly. It commonly means thorough study of the geology of the entire region surrounding the ore deposits. THE following question has been suggested for discussion: ? "Are there any criteria by which one can determine when mining operations have reached the roots of an ore deposit?" The question deals less with the roots of a particular ore body than with the lower limit of the vertical range within which ore bodies may be expected. It concerns a critical line upon the longitudinal vertical projection of a vein. ? Below this line it is useless to look for ore shoots; above the line exploration below the bottoms of individual ore shoots may be justified. Can we learn to determine the position of such a line?

Jan 1, 1939

By Sir Robert Hadfield

(New York Meeting, February, 1913.) THE Hadfield method of producing sound steel ingots has been the subject of a paper 1 read before the Iron and Steel Institute, so that it will be unnecessary to describe it fully here. The object of the method is to make possible the production of steel ingots in which the pipe is almost entirely obliterated, and it is applicable particularly to the production of sound ingots, from which good rails could be rolled. The method in brief consists in casting the ingots on cars, usually with the small end down. Each ingot mold is provided with a sand top, rammed up in the well-known manner. After the mold is filled to the desired height with steel, a layer of slag about 0.5 in. thick is placed upon it and the balance of the mold is then filled with charcoal. Then, through suitable piping, an air blast is directed in numerous jets upon the charcoal, which is burned thereby, the combustion supplying additional beat to the top of the ingot, which helps to keep the top fluid and to retard its solidification, while the lower parts are rapidly losing heat by its transfer to the mold. By-one plan the ingots are cast in molds placed upon bogies, movable trucks, or platforms, in the position A, Fig. 1. The ingots are cast vertically on bogies, say four or more ingots on each bogie, as may be found most convenient, and the upper surface of the steel is maintained in a molted condition during the transit of the ingots from the casting pit to the stripper. This is effected by a series of air pipes, for example, three in number, with jets or holes on the under surface of such pipes, placed preferably horizontally, arranged in such a manner as to cause jets of air to impinge on the upper surface of the ingots. These holes or jets are made throughout the entire length of the overhead pipes, the length of such pipes being

Jan 4, 1913

By J. Lyden

In the Picher field, structure made openings for the circulation of the mineralizing solutions by flexing, shearing, and fracturing the sedimentary beds. This structure is used with the spatial and genetic relationship of the ore minerals, sphalerite and galena, and the gangue minerals, dolomite and jasperoid, in prospecting for ore bodies. THE Picher Mining Field, fig. 1, which lies between Baxter Springs, Kansas, and Commerce, Okla., is the most intensely mineralized and the largest zinc-lead ore producing area in the Tri-State District of Missouri, Kansas, and Oklahoma. It has a vast lateral extent of underground workings that is unequaled for the observation of the geology of zinc-lead ore bodies in sedimentary horizons; and thousands of churn drill holes in the unmined areas supplement the underground observations with useful data for the interpretation of the geology. This paper is confined to the ore deposits of the Picher mining field. The reader is referred to the bibliography for the general geology of the Tri-State district which has been ably covered by many geologists. The writer was co-author of several publications on the Tri-State district.'-" This paper is necessarily a repetition of parts of those publications but contains a few changes and additions on the deposition of the minerals. The parts of this paper concerning mineralization maps and pipe slump-structures are not covered in the above publications. Geology The geology of the Picher mining field is similar to that of the entire Tri-State district because the sedimentary horizons that are found here are found throughout the district, and the ore bodies in the respective horizons have similar characteristics. The beds that contain the ore bodies in the Picher field are illustrated and described in fig. 2. The five unconformities found in the mines of the Picher field are indicated on the geologic section, fig. 2. The unconformity shown at the base of Meramec (B bed) is relatively unimportant since B bed was mostly eroded from the area of the Picher field before the Chester beds were deposited. B bed has been observed in the cuttings from only a few churn drill holes. The Pennsylvanian (Cherokee shale) formation is the top horizon found in the Picher mining field. It has been eroded from the southeastern part of the field, but because of the regional dip of the sedimentary beds to the west, it attains thicknesses of 100 ft to 200 ft along the west edge of the field. It is 200 ft to 300 ft thick in the Miami trough. It was deposited on the Boone limestone surface, which contained relatively few shallow erosion channels and very few depressions. Subsequent to the deposition of the shale, solution of limestone from underlying limestone horizons by circulating solutions caused the overlying beds, including the Cherokee shale, to slump into the larger openings formed by the solution and removal of the limestone. Chert The origin of the chert in the Tri-State district has been a controversial subject among geologists. Tarr7 advocated a syngenetic origin for the chert, postulating that it formed from colloidal silica deposited in the Mississippian seas. Leith, Dake and Leighton' argued in favor of silicification of erosion

Jan 1, 1951

By J. Lyden

In the Picher field, structure made openings for the circulation of the mineralizing solutions by flexing, shearing, and fracturing the sedimentary beds. This structure is used with the spatial and genetic relationship of the ore minerals, sphalerite and galena, and the gangue minerals, dolomite and jasperoid, in prospecting for ore bodies. THE Picher Mining Field, fig. 1, which lies between Baxter Springs, Kansas, and Commerce, Okla., is the most intensely mineralized and the largest zinc-lead ore producing area in the Tri-State District of Missouri, Kansas, and Oklahoma. It has a vast lateral extent of underground workings that is unequaled for the observation of the geology of zinc-lead ore bodies in sedimentary horizons; and thousands of churn drill holes in the unmined areas supplement the underground observations with useful data for the interpretation of the geology. This paper is confined to the ore deposits of the Picher mining field. The reader is referred to the bibliography for the general geology of the Tri-State district which has been ably covered by many geologists. The writer was co-author of several publications on the Tri-State district.'-" This paper is necessarily a repetition of parts of those publications but contains a few changes and additions on the deposition of the minerals. The parts of this paper concerning mineralization maps and pipe slump-structures are not covered in the above publications. Geology The geology of the Picher mining field is similar to that of the entire Tri-State district because the sedimentary horizons that are found here are found throughout the district, and the ore bodies in the respective horizons have similar characteristics. The beds that contain the ore bodies in the Picher field are illustrated and described in fig. 2. The five unconformities found in the mines of the Picher field are indicated on the geologic section, fig. 2. The unconformity shown at the base of Meramec (B bed) is relatively unimportant since B bed was mostly eroded from the area of the Picher field before the Chester beds were deposited. B bed has been observed in the cuttings from only a few churn drill holes. The Pennsylvanian (Cherokee shale) formation is the top horizon found in the Picher mining field. It has been eroded from the southeastern part of the field, but because of the regional dip of the sedimentary beds to the west, it attains thicknesses of 100 ft to 200 ft along the west edge of the field. It is 200 ft to 300 ft thick in the Miami trough. It was deposited on the Boone limestone surface, which contained relatively few shallow erosion channels and very few depressions. Subsequent to the deposition of the shale, solution of limestone from underlying limestone horizons by circulating solutions caused the overlying beds, including the Cherokee shale, to slump into the larger openings formed by the solution and removal of the limestone. Chert The origin of the chert in the Tri-State district has been a controversial subject among geologists. Tarr7 advocated a syngenetic origin for the chert, postulating that it formed from colloidal silica deposited in the Mississippian seas. Leith, Dake and Leighton' argued in favor of silicification of erosion

Jan 1, 1951

By Mary Louise Theodore, R. G. Aspden, D. A. Colling

T RACES of sulfur have a marked influence on the physical and mechanical properties of many iron-base alloys. The commonly used combustion method for the determination of sulfur content is not accurate enough at the 50 ppm level by weight and below to be useful in determining the influence of sulfur. Kriege and Wolfe' have described a method for the determination of sulfur in iron alloys in which the sulfur is evolved as hydrogen sulfide followed by reaction with N, N-dimethyl-p-phenylenediamine, and iron (111) to form methylene blue which is measured spectrophoto-metrically. This method of determining sulfur has been used to study the activity of sulfur in Fe-Si-S alloys,' but has not been previously applied to the determination of sulfur in Fe-Ni alloys because of the insolubility of nickel in dilute hydrochloric acid. Dissolution of nickel in dilute hydrochloric acid, however, can be greatly accelerated by the addition of a small amount of platinic chloride.3 By combining these two techniques in a procedure in which 0.005 pct platinic chloride in 1:l hydrochloric acid is used as the dissolving fect on the strength of the material. However, ductility is influenced by the presence of discontinuous precipitation. In Fig. 5, percent elongation data at room temperature and 1400°F is shown for two sets of specimens of Waspalloy which were solution heat treated at 1950°F and either quenched or slow cooled to the aging temperature and then aged for 100 hr at 1292" and 1598ºF, respectively. At room temperature the existence of a discontinuous precipitation cell at grain boundaries (see data point marked by arrow) has no apparent effect on ductility. However, at elevated temperatures a pronounced lowering of ductility occurs when discontinuous precipitation has occurred in the specimen. It would appear that the morphology of discontinuous precipitation "cells" at grain boundaries would be highly conducive to the initiation of cracks which in turn lead to premature "grain boundary" failure.

Jan 1, 1970

By J. B. Sellers, G. R. Haworth, P. G. Zambas

Rock mechanics research was carried out in the Anvil Points mine, Rifle, Colo., in the period 1964-1968, with the dual purpose of providing oil shale to the retorts of six major oil companies and to perform research on mining cycle operations to maximize extraction under safe conditions. An 80% extraction ratio within the mining area proved feasible. Test results provided data on optimum pillar and roof design. Studies of mine orientation showed that the mining headings should take into account the prevailing joint patterns and also the directions of the principal in-situ stresses acting in the region.

Jan 1, 1973

US 4,186,083-An improved collector for use In the froth flotation beneficiation of phosphate rock, barite, fluorspar, scheelite or Iron oxide ore comprises 70 to 99.9% by weight of tall oil fatty acid or the like and the remainder a described anionic perfluorosulfonate compound. Reagent consumption is lessened, and high recovery at high grade is effected. S.S. Wang, E.L. Smith, Jr., and E. F Huliganga, assigned to American Cyanamid Co. Jan 29, 1980. 4 pp. (209-166). Filed. 12-21-77 (863,034).

Jan 1, 1982

By W. B. Mather

Literature dealing with rock drilling presents a mass of conflicting data. The principal cause of the confusion is attributed to varying definitions of the hardness factor of rock and cutting media. The future development of more efficient drilling methods demands that this problem be solved. The first step in the solution is the compilation of complete data on the physical properties of rocks.

Jan 2, 1951

By Lawrence F. Schubert

Instrumentation is not a stranger to the minerals processing industry. In fact, very few plants now exist that haven't to one extent or another adapted operations to instrumentation. But with the rapid growth of such controls has come the need for effective departments composed of men trained to maintain and repair the instruments; here is where many firms fall short. The importance of the role an instrument department should play is underscored by the omnipotent effects which instruments often exert over an operation. Reserve Mining Co. is an example: while instrumentation at this taconite plant represents approximately 2% of the process equipment cost, a breakdown of instruments may result in the ineffective use (or complete shut-down) of the other 98% of plant investment.

Jan 7, 1966