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By J. E. Johnson

The description of the machine which coilstitutes the subject of this paper is best iutroduced by a statement of the conditions which led to its construction, which may be briefly given as follows : The ore handled at the plant to be here described* is of the variety sornetimes called by those familiar with the brown ores of the South, " Mountain," as distinguished from the " Lime-

Jan 1, 1899

By David G. Chedgy

The Meadow River No. 1 preparation plant, owned by Sewell Coal Co. which is a subsidiary of the Pittston Co., was commissioned in the spring of 1974. A survey of the environmental noise levels was conducted, and the dominant noise sources identified. An engineering program was initiated to reduce the prevailing levels to a point that the operator's exposure would be within compliance with the MESA regulation for ear protection. The program was continued until compliance was achieved and the attenuation factors for each abatement device recorded. The highlights of this program will be presented with a discussion of the practicality of the devices utilized.

Jan 1, 1977

By Jr. E. H. Dix.

In selecting the subject, "Acceleration of the Rate of Corrosion by High Constant Stresses,'' for the 1940 Institute of Metals Division Lecture, I have been influenced by its highly theoretical and speculative nature as well as by the great practical importance of the correct interpretation and appraisal of the engineering significance of the phenomenon. I lay no claim to originality in talking on this topic, since it has been the subject of discussion for over a quarter of a century. However, as our technical thinking advances, old phenomena take on new and more significant aspects. In our studies at the Aluminum Research Laboratories, we have encountered many perplexing and seemingly contradictory results and have been fascinated by the problem of dovetailing all of the many pieces of information to make a complete picture. I hope that in the brief period of this lecture I may share with you some of the enjoyment we have had in attempting to meet this challenge to metallurgical science. The emphasis generally has been placed on the spontaneous failure by cracking of a metal under the combined action of high stress and corrosion, hence the present-day use of the terms "stress corrosion" or "stress corrosion cracking." The older term "season cracking," applied more specifically to copper-base alloys, includes, by inference, the element of time. For the purpose of the discussion today I will use "stress corrosion" to cover broadly the effect of stress in accelerating the rate of corrosion of metals. To stay within the limits of allotted time the disrussiorl will cover the effect of high static stresses rather than repeated or dynamic stresses, which would take us into the related field of corrosion-fatigue. The subject is particularly appropriate for an Institute of Metals Division Lecture because much the same phenomenon has been observed in almost all metal systems. Thus, in addition to the season cracking of brass may also be mentioned the "caustic embrittlement" of steel boiler

Jan 1, 1940

By Jr. E. H. Dix.

In selecting the subject, "Acceleration of the Rate of Corrosion by High Constant Stresses,'' for the 1940 Institute of Metals Division Lecture, I have been influenced by its highly theoretical and speculative nature as well as by the great practical importance of the correct interpretation and appraisal of the engineering significance of the phenomenon. I lay no claim to originality in talking on this topic, since it has been the subject of discussion for over a quarter of a century. However, as our technical thinking advances, old phenomena take on new and more significant aspects. In our studies at the Aluminum Research Laboratories, we have encountered many perplexing and seemingly contradictory results and have been fascinated by the problem of dovetailing all of the many pieces of information to make a complete picture. I hope that in the brief period of this lecture I may share with you some of the enjoyment we have had in attempting to meet this challenge to metallurgical science. The emphasis generally has been placed on the spontaneous failure by cracking of a metal under the combined action of high stress and corrosion, hence the present-day use of the terms "stress corrosion" or "stress corrosion cracking." The older term "season cracking," applied more specifically to copper-base alloys, includes, by inference, the element of time. For the purpose of the discussion today I will use "stress corrosion" to cover broadly the effect of stress in accelerating the rate of corrosion of metals. To stay within the limits of allotted time the disrussiorl will cover the effect of high static stresses rather than repeated or dynamic stresses, which would take us into the related field of corrosion-fatigue. The subject is particularly appropriate for an Institute of Metals Division Lecture because much the same phenomenon has been observed in almost all metal systems. Thus, in addition to the season cracking of brass may also be mentioned the "caustic embrittlement" of steel boiler

Jan 1, 1940

By Henry S. Brown, Jean E. Tilden

Pyrite, pyrrhotite, chalcopyrite, and sphalerite from deposits distributed within the Piedmont and Blue Ridge provinces of North Carolina and adjacent areas were examined by atomic absorption spectrophotometry for cobalt, nickel, manganese, lead, tin, chromium, molybdenum, and gold. The ore samples were also examined petrographically. Cobalt and nickel, in general, enter pyrite and pyrrhotite rather than chalcopyrite and sphalerite. Manganese generally enters sphalerite rather than the other phases where an alternative is possible. The presence of tin in sulfide minerals was noted in a group of deposits east of the known occurrences of tin oxide (cassiterite) in the Kings Mountain belt, which may indicate the presence of a more extensive tin belt in the southeastern Piedmont than was previously recognized. Pyrrhotite from a group of four deposits in Jackson and Clay Counties, North Carolina, differs from pyrrhotite from other Ducktown-type deposits in having cobalt/ nickel ratios less than one, finer grain sizes, and colloform texture. These differences suggest that that this group of deposits has had a history different from that of the other Ducktown-type deposits studied. No significant conclusions could be made based on the distribution of lead, chromium, molybdenum, or gold.

Jan 1, 1975

Charles Catlett, Staunton, Virginia (communication to the Secretary*): I have had occasion to examine a few of the irondeposits in the immediate section of which Mr. Watson speaks, but have not had an opportunity to visit any of the well-known manganese-deposits. I find the former can be very safely read in light of the information which it is possible to get from the same measnres farther. north, where they are less completely decomposed. In the same way all of his conclusions in regard to the geology of the manganese-deposits bear out their occurrence in Virginia, when we allow for the far more complete decomposition in the section he has so carefully studied. Judging from the same measures farther north, I think he will be safe in agreeing even further with Penrose as to the origin of these ores. Some years ago I carried on prospecting work in these measures in Virginia, in which the iron-ore and manganese-ore were followed down to undecomposed material, and in which their occurrence along a definite line of stratification, and apparently a part of the original bedding, was plainly shown. This is unusual, however, even in the section of which I speak. At Crimora, Virginia, the decomposition is quite complete; at the same time the results of some hydraulic work, which has been done there, disclosed, at the time of my last visit, the manganese interbedded in the residual clay along a definite and distinct plane parallel to the bedding of the underlying quartzite, and which, as is shown at other points, corresponds with the plane of the original material. In view of the phosphorus reported by Mr. Watson as existing in the Cartersville ores, and the not uncommonly prohibitive amount in southern ores, I am interested to know whether

Jan 1, 1904

Henry Louis, Newcastle-upon-Tyne, England (communica, tion to the Secretary): I have been much interested in Mr. Schmitz's description of the copper-ore bed in the Permian formation of Texas. He compares it with the Mansfeld Kupferschiefer; but it seems to me to present closer analogies with a small deposit on the same side of the Atlantic, in Nova Scotia, which I examined in 1877. I quote entirely from my fieldnotes, made then, and from specimens still in my possession. These copper-deposits are known in several places; but I examined them at the village of New Annan, on the banks of the French river. This district has been determined by Sir J. W. Dawson as being of Permian age, and this determination seems to have been confirmed as recently as 1891 by the operations of the Canadian Geological Survey. The following is the section, very imperfectly exposed in a few shallow levels, described in ascending order: Red sandstone, moderately fissile and markedly false-bedded. Lower nodule-bed, 1 inch to 6 inches thick, of fissile mica, ceous sandstone, containing obscure plant-remains converted into anthracite, chalcopyrite, chalcocite and iron pyrites. Very coarse grit or, in places, red sandstone; thickness and character variable. Upper nodule-bed, 6 inches to 2 feet thick exceptionally, generally about 10 inches. Soft, gray, friable shaly sandstone, with nodules of copper-ore. Red sandstone. All these strata lie flat, in places quite horizontal, in places dipping towards the river at 5° to 10°.

Jan 1, 1897

By Earl Greiner

THE constitution of the iron-silicon alloys containing from 14 to 33.4 weight per cent silicon has been studied by a number of investigators, whose results have been reviewed in a monograph published by the Engineering Foundation1. In these previous researches, the solubility of silicon in iron was determined by thermal, microscopic or magnetic methods and the compound Fe3Si2 was reported to be stable at tempera-tures from 0 to approximately 1030° C. This paper describes the results of an X-ray investigation of the solubility of silicon in iron and gives data which prove that the Fe3Si2 phase is unstable below 825° C. In order to obtain the present results on the solubility of silicon in iron, the authors have utilized the lattice constants of the alpha-phase iron-silicon alloys given in a previous publication2, and also some addi-tional data which will subsequently be described.

Jan 1, 1936

By P. E. Chapman, J. E. Worthington, I. T. Kiff

Increases in the price of gold starting about six years ago, and rapid fluctuations since then, have created a substantial popular interest in the noble metal. Gold prospecting had been at a low ebb since the end of World War II in most of the United States, except for a flurry of activity in Nevada after the Carlin and Cortez discoveries. The last few years, however, have seen a great awakening of interest in gold exploration as well as an opportunity for education for many explorationists in the geology and other vagaries of gold deposits. The writers have participated over the last few years in a search for gold deposits throughout the United States. This search was greatly influenced by the geologic studies of Dr. William Spence at the Haile gold mine in South Carolina, as reported in a companion paper. Spence's studies resulted in definition of a geologic model that has proven useful in a number of other geologic environments in the United States. These programs were all carried out under the auspices of Cyprus Mines Corp. and permission by Cyprus to present these results is gratefully acknowledged. The writers, however, reserve for themselves all responsibility for the results and conclusions. The exploration program to be described began in the southeastern United States. Spence's studies provided a reasonable basis for interpreting and understanding the geology of the Haile deposit, and also provided a means for predicting additional occurrences. This concept was then expanded to other gold occurrences in the Piedmont, and became an effective tool for evaluating other prospects. Finally, it became evident that the concept could be applied in some western gold districts. The following discussion will then include descriptions of other Piedmont examples and a few western districts that also appear to fit the pattern.

Jan 1, 1981

By George Scott

MANY requests for information as to the possibility of washing coals to some predetermined percentage of ash or sulfur have suggested that the producers aim to satisfy some degree of purity set by the user of the fuel, rather than to attain the greatest economic benefit to all concerned. This paper is written to show that the highest economic purity of washed coal can be determined from washability studies of the raw coal, costs of mining and washing coal, and data on the effect of ash and sulfur on the value of the coal for the particular use for which it is intended.

Jan 1, 1929

By C. M. Moncrief, B C. Craft

A bentonite-clay drilling mud when treated with tetrasodium pyroarsenate underwent substantially the same reduction in viscosity and water loss as when treated with the complex phosphates. The complex arsenate showed a slightly higher reversion after heating; the other arsenates showed poor viscosity-reducing properties. Introduction During the past 10 years the chemical control of drilling mud has become of major importance in affecting the successful drilling and working over of wells. The desired properties of drilling mud have been well established, and in obtaining these characteristics there has developed a large market for viscosity-reducing chemicals. Viscosity reduction produced by humic acid, tannic acid, sodium silicate, sodium tannate, Calgon, and the complex phosphates has been described by Loomis, Ford, and Fidiam.l The effects Of treatment with complex phosphates and ammonium PolyPhosPhates on the rheological properties of muds were investigated by Fancher2 and the alkali vanadates have been described by Williams.3 Laboratory Investigations It is the purpose of this paper to point out the effects of arsenates in controlling the viscosity and gelling characteristics of a drilling mud. Viscosities and gel strengths were measured at room temperatures with a Stormer viscosimeter calibrated in centipoises and operated at 600 r.p.m. Water loss was determined at 80°F. with the Baroid low-pressure wall-building tester at a pressure of I00 lb. per sq. in. for 30 min. The hydrogen-ion concentration was measured with a glass electrode. The bentonite-clay suspensions were prepared in the laboratory and allowed to age several days before testing. Members of the Arsenic Group in the periodic Table include arsenic, antimony and bismuth, but this investigation was limited to arsenic. Phosphorus also occurs in Group V of the Periodic system and phosphorus and arsenic form many closely related compounds such as pH3 and AsH3, P2O5 and As2O5, H3PO4 and H3AS04 Samples of tetrasodium pyroarsenate were prepared by fusing c.p. disodium arsenate (Na2HA5O4.7H2O). According to Friend,' this re-forms the ortho-arsenate on dissolution in water. Sodium trihydrodiorthoarsenate was prepared as described by Mellor,5 from arsenic pen-toxide as follows: As2O5 + 3H20 -> 2H3AsO4 2H3AS04 + 3NaOH Na3H3(AsO4)2 .3H20 Sodium dihydrogen orthoarsenateWaHz-As04) was obtained by fusing together equivalent quantities of arsenious Oxide and sodium nitrate, dissolving the residue in water and allowing it to crystallize.

Jan 1, 1946

By C. M. Moncrief

A bentonite-clay drilling mud when treated with tetrasodium pyroarsenate underwent substantially the same reduction in viscosity and water loss as when treated with the complex phosphates. The complex arsenate showed a slightly higher reversion after heating; the other arsenates showed poor viscosity-reducing properties. Introduction During the past 10 years the chemical control of drilling mud has become of major importance in affecting the successful drilling and working over of wells. The desired properties of drilling mud have been well established, and in obtaining these characteristics there has developed a large market for viscosity-reducing chemicals. Viscosity reduction produced by humic acid, tannic acid, sodium silicate, sodium tannate, Calgon, and the complex phosphates has been described by Loomis, Ford, and Fidiam.l The effects Of treatment with complex phosphates and ammonium PolyPhosPhates on the rheological properties of muds were investigated by Fancher2 and the alkali vanadates have been described by Williams.3 Laboratory Investigations It is the purpose of this paper to point out the effects of arsenates in controlling the viscosity and gelling characteristics of a drilling mud. Viscosities and gel strengths were measured at room temperatures with a Stormer viscosimeter calibrated in centipoises and operated at 600 r.p.m. Water loss was determined at 80°F. with the Baroid low-pressure wall-building tester at a pressure of I00 lb. per sq. in. for 30 min. The hydrogen-ion concentration was measured with a glass electrode. The bentonite-clay suspensions were prepared in the laboratory and allowed to age several days before testing. Members of the Arsenic Group in the periodic Table include arsenic, antimony and bismuth, but this investigation was limited to arsenic. Phosphorus also occurs in Group V of the Periodic system and phosphorus and arsenic form many closely related compounds such as pH3 and AsH3, P2O5 and As2O5, H3PO4 and H3AS04 Samples of tetrasodium pyroarsenate were prepared by fusing c.p. disodium arsenate (Na2HA5O4.7H2O). According to Friend,' this re-forms the ortho-arsenate on dissolution in water. Sodium trihydrodiorthoarsenate was prepared as described by Mellor,5 from arsenic pen-toxide as follows: As2O5 + 3H20 -> 2H3AsO4 2H3AS04 + 3NaOH Na3H3(AsO4)2 .3H20 Sodium dihydrogen orthoarsenateWaHz-As04) was obtained by fusing together equivalent quantities of arsenious Oxide and sodium nitrate, dissolving the residue in water and allowing it to crystallize.

Jan 1, 1946

By Theodore B. Comstock

The paper of Mr. S. F. Emmons on the structural relations of ore-deposits, presented at the Boston meeting in February last, having been, as I am informed, unavoidably delayed in publication, was not distributed in the preliminary edition to members until immediately before the sheets of Volume XVI. of the Transactions, containing it, were sent to press. Consequently, I saw it for the first time too late to offer any comments which might have accompanied it in that volume. This is my justification for present-

Jan 1, 1889

By D. M. S. Bhatia, Richard D. Hagni

Five sulfide minerals from the Magmont mine, southeast Missouri were sampled for 31 trace elements in over 300 samples by laser microprobe spectrographic analysis of polished sections. The concentration of several trace elements shows a pattern of progressive variation with depth (space) and variation with different paragenetic stages (time) of each mineral. Factor analysis of the geochemical data shows sympathetic correlation both in space and in time of Bi, Cd, Ge, and Sn in galena and sphalerite, and Ni and Co in sphalerite and marcasite.

Jan 1, 1981

By A. F. Crawley

THIS communication reports measurements of the densities of dilute liquid alloys of 0.1 and 0.5 pct Ag in Sn over temperature ranges of 170" and 210°C, respectively, above the melting point of pure tin (232°C). The work was earried out to provide accurate density data for some liquid diffusion studies performed by Davis.1 Densities were measured using a pycnometric technique established in this laboratory. Earlier papers2, 4 attest to the accuracy of ±0.05 pct and the reliability of the method. Tin, 99.999 pct pure, and silver 99.99 pct pure, were melted in a graphite crucible in a vacuum furnace and held at temperature for 10 hr to ensure homogenization. Ingots suitable for machining

Jan 1, 1970

By F. R. Pyne

The following notes are presented in an endeavor to point out the disadvantages attending the use of chrome brick in reverberatory furnaces in which are conducted the treatment of materials of such a nature that absorption by the brick is of too great value to be wasted, and these values must be recovered, if possible, in order to prevent metal losses that can not be tolerated. Several years ago one of the large Eastern copper refineries decided to utilize basic material in place of siliceous material in the walls of their reverberatory furnaces for the treatment of very foul blister copper, as the latter rapidly corroded the siliceous linings. It was also expected that there would be less slag formation, with a consequent decrease in the cost of treatment and a reduction in the metal losses. Magnesite brick were first used, but while the corrosive action of the foul material was greatly reduced, and the amount of slag formed was very much less, the magnesite proved to be unsatisfactory in certain parts of the furnace, because of its tendency to crack and spall badly when subjected to the alternate heating and cooling that takes place in a reverberatory refining furnace. This made many repairs necessary, and consequent frequent interruption in the operation of the furnace, which, together with the high price of the magnesite brick, ran up the cost of maintenance to an unreasonable amount. It was, therefore, decided to substitute chrome brick for magnesite brick in the parts of the furnace affected. The results, as far as the reverberatory furnace was concerned, were very satisfactory. The corrosion due to the action of the foul blister was small and the amount of slag formed was no greater than when using magnesite, and the tendency to crack and spall shown by the magnesite was eliminated. Gradually the use of chrome brick was extended to all furnaces, those treating blister copper as well as those melting cathodes, and the results were so satisfactory that the siliceous roofs were replaced by roofs of chrome brick except in certain places where experience showed a more satisfactory performance on the part of the silica brick. It was immediately recognized, for both the magnesite and the chrome brick, that the metal absorption was very heavy, but it was felt that the

Jan 1, 1918

By J. O. Lewis, Carl H. Beal

Introduction ............................... 492 Theories Relating to the Recovery of Oil.................. 493 Methods Commonly Employed for the Estimation of Future Production..... 495 Saturation Method........................... 495 Production Curve Method....................... 496 Production per Acre Method.....................: 496 Appraisal Curves.............................. 498 Derivation and Construction...................... 498 Comparison of Appraisal Curves of the Osage and Nowata Fields...... 505 Use of Appraisal Curves........................ 506 Accuracy of the Apprais?l Curves and Their Sources of Error........ 508 Relation Between Future Productions of Wells of Equal Output....... 510 Use of Appraisal Curves for the Derivation of Generalized Future Decline Curves. 513 Theory of Generalized Curves Showing the Decline in Production...... 513 Suggested Methods for Making Closer Estimates.............. 517 Use of Logarithmic Coordinate Paper.................... 518 Summary................................ 520 Introduction Oil wells usually reach their maximum daily output shortly after they are completed. From that time they decline in production, the rapidity of decline depending on the output of the wells and on other factork governing their productivity. The production curve of a well shows the amount of oil produced per unit of time for several consecutive periods; if the conditions affecting the rate of production are not changed by outside influences, the curve will be fairly regular, and, if projected, will furnish useful knowledge as to the future production of the well. By the aid of this knowledge the value of a property maybe judged, and proper depletion and depreciation charges may be made on' the books of the

Jan 1, 1918

By F.M. Walters

In order to isolate the effect of an element on some property of an alloy, the effect of the other alloying elements must be elimi-nated, either by reducing their quantity to the extent that they may be neglected or by determining the specitic effect of each. The success of Grossmannl in calculating hardenability from chemical composition by means of factors suggested such a

Jan 1, 1943

By F. M. Walters

In order to isolate the effect of an element on some property of an alloy, the effect of the other alloying elements must be elimi-nated, either by reducing their quantity to the extent that they may be neglected or by determining the specitic effect of each. The success of Grossmannl in calculating hardenability from chemical composition by means of factors suggested such a

Jan 1, 1943

By O. Vartiainen, R. T. Hukki

A preliminary investigation of the collecting effects of various fatty acids in tall oil has led to a conclusion that the collecting power of fatty acids used in flotation increases with increasing unsaturation of the hydrocarbon chain, Linoleic acid was found to be an excellent collector for oxide minerals.

Jan 8, 1953