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By S. F. Shaw

IT IS generally recognized that the natural gas absorbed in petroleum plays the leading r6le in moving the oil through the sands to the well and supplies the energy that delivers the oil to the surface when the wells are flowing. It is the purpose of this paper to note the amount of oil that could be lifted by this gas if 100 per cent. efficiency were obtained and the efficiencies actually obtained in the use of this gas. An article in MINING AND METALLURGY,' stated that in a Wyoming field, with a pressure of 300 lb. per sq. in., there would be absorbed 65 cu. ft. of gas per barrel, or 1.55 cu. ft. per gal. of oil. The writer does not know if data have been obtained, by experiment, for pressures beyond those indicated in this article, therefore, for the purpose of illustration, he has projected this curve to obtain figures for pressures greater than 300 lb., although probably experiment will show that the extended line is not quite correct.

Jan 1, 1926

By W. A. Backofen, D. H. Avery, G. A. Miller

An evaluation has been made of the relative importance of yield strength (?) and stacking-fault energy (y) to the rate of fatigue-crack growth in materials of fcc structure. Pure copper and its solid-solution al-loys with aluminum and nickel were chosen for the study because they provided sufficient range in both quantities of interest that either could be varied independently of the other. Experiments involved alternating tension and compression of flat specimens which were prepared with sharpened internal notches so that most, if not all, of the crack-nucleation interval could be eliminated. Growth rate (dC/dN) was concluded to be proportional to the square of the plastic-strain amplitude (€,,) over a strain range of approximately 6x 10-4 to 6 x 10-3. The factor, k, linking dC/dN and ep in dC/dN = kEp2 increased and decreased with corresponding variations in y, but it did not respond syste?>/atically to change in ay, indicating that y is the significant variable in crack growth at constant plastic-strain amplitude. In polycrystalline material, k varied by a factor of 5 over the available range of y. In a few single-crystal experiments on Cu-A1 alloys the growth rate responded less strongly to change in y. It has been suggested that single crystals behave somewhat differently than poly crystalline material because there is more extetnsive substructure near the grain boundaries in the latter, and this facilitates crack advance by separation along subgrain boundaries. A point of some controversy in current work on fatigue relates to the effects of strength and stacking-fault energy on crack growth. In recent experiments a separation was made between the cycling intervals for crack nucleation and the subsequent growth that eventually ends a specimen's fatigue life.' The study was carried out on Cu-A1 alloys primarily, fatigued in alternating four-point bending to constant deflection. A nucleation interval of about 10' cycles (at a total strain amplitude = 0.2 pct) was found to be insensitive to aluminum content in the range 0 to 7.5 wt pct, while the growth period was increased approximately forty fold over the same compositional range. The increase was not in any sense linear, however. Rather, most of the change occurred below 4 pct A1 or a stacking-fault energy, ?, of about 15 ergs per sq cm. It was argued that the plastic-strain amplitude was approximately constant, and therefore the effect of composition must have grown out of the reduction in stacking-fault energy. Several studies have shown that, with high ?, cross slip is encouraged, subgrain structure is introduced during fatigue, and cracking is aided through propagation along subgrain boundaries.1-5 Therefore, lowering ? sufficiently to interfere with substructure formation would be expected to retard growth rate. On the other hand, it is a general rule that resistance to fatigue cracking increases as strength is raised. Accordingly, there might still have been some doubt that Y was the controlling variable, since strength would be increased as y was lowered by the aluminum additions. To help in dispelling that doubt, an experiment was made on a polycrystalline Cu-Ni alloy similar in strength to the Cu-A1 alloys but of higher ?; the crack-growth interval was found to be essentially that of pure copper.' Further support for this position on stacking-fault energy as it relates to crack growth is derived from work by Boettner and McEvily,6 in which the actual crack-growth rate was measured on samples previously notched so as to minimize the nucleation period. Unfortunately, it was necessary in isolating strength level to compare different alloy systems and grain sizes. Recognizing the complication, it was still concluded that growth may be retarded by a reduction in y, per se. A related study has also been made by Roberson and Grosskreutz.7 The zinc content of a brass was systematically changed to alter strength and stack-ing-fault energy, although not below the 15 ergs per sq cm at which pronounced change in growth interval was found in the earlier work. The results were limited to more or less conventional S-N diagrams so that nucleation and growth events could not be separated. No definite conclusions were drawn, but

Jan 1, 1967

By P. E. Busby, C. Wells, M. E. Warga

Fundamental data on the rate of diffusion of boron in austenite and solubility of boron in the a and y phases of iron and steel have been obtained from deboronizing experiments and provide partial explanations for some of the phenomena observed in boron steels. The rate of diffusion of boron is about the same as carbon in austenite. The solubility of boron in austenite at normal heat-treating temperatures is less than 0.001 pct. A partial tentative Fe-B phase diagram in the important low boron concentration ranges and an equation representing the diffusion of boron in austenite are presented. A LTHOUGH a search of the literature revealed ALTHOUGHthat boron diffusion had not been studied quantitatively and systematically prior to 1948, a few qualitative observations which were made by following the diffusion of boron into iron packed in ferro-boron1-3 suggest that boron obeys normal diffusion laws and that the rate of diffusion increases with increasing temperature. The claim of Cornelius and Bollenrath1 that boron does not appear to influence the rate of carbon diffusion has recently been substantiated by Wells, Batz, and Mehl.4 Calculations based on data from the paper by Campbell and Fayv indicated that the diffusion coefficient (D) for boron in iron at 900°C is approximately 3x10 sq cm per sec; a value of 2x10-7 sq cm per sec at 1038°C has been reported by Digges et al in connection with decarburizing experiments on a commercial boron steel containing 0.43 pct C. During the period 1948 to 1950 several diffusivity constant (D) values for the diffusion of boron in the y phase of iron and steel and a number of solubility values for boron in both a and y phases were reported. It was concluded tentatively as a result of Metals Research Laboratory studies that D values for boron in y and a phases are about the same as for carbon in the comparable phasesa and that carbon up to 0.4 pct did not affect the rate of diffusion of boron in y iron above 1000°C within the limits of experimental error. Whether saturation of the y or a phases with carbon would significantly affect rates of diffusion of boron through them was then and still remains in doubt. The best estimate of Q (activation energy) was reported to be about 25,000 cal, somewhat lower than that for carbon in y iron. The solubility of boron in y iron at 1000°C was thought to be higher than 0.004 pct B but not as high as a more recent analysis of available data shows it to be. The solubility of boron in a iron at 700°C was reported to be 0.0004 pct B, but it would not have surprised the authors if the true solubility value is actually lower than this. Breaks in diffusion curves which were not understood when first obtained prior to 1950 have now been recognized as indicating solubility limits, and these are included in the present paper. Experimental Procedure Two methods were employed in an effort to determine diffusion coefficients (D) for boron in austenite. Early experiments involved the use of welded couples prepared in accordance with the procedure of Wells and Mehl,' but when the results of these experiments proved to be unsatisfactory for calculating D values, studies were continued by means of deboronizing experiments. In both cases, boron analyses following the diffusion anneal were carried out spectrographically and all D values were computed using the Grube solution of Fick's law. The precision of the spectrographic method used proved to be about equal to that reported by Corliss and Scribner" —average deviation from the mean about 5 pct of the amount present when the boron content is 0.003 pct. Concentration-penetration curves obtained from spectrographic analyses of welded couples generally indicated that practically no boron was transported across the weld interface during the diffusion anneal. Furthermore the concentration-penetration

Jan 1, 1954

By John G. Hall

The unstable metal market during 1949, with resulting lower metal prices, has focused every mine operator's attention on the problem of reducing operating costs. Improvement in mining, methods, use of modern mechanical mining equipment, and increasing the efficiency of the labor force are the tools with which we will have to work. Careful planning is necessary to coordinate all phases so that no one phase is overdone. A mine may become over-mechanized if, for instance, capital charges against new equipment exceed the savings in labor costs, or where a large enough tonnage is not produced. The cooperation, of labor is essential to any mechanization program. There have been too many instances where mechanization and improvements have done nothing more than make up for a decrease in labor efficiency, thus bringing the production of labor back to its old standard. The operator has gained little and labor has gained only a "softer job." In any mechanization program there are gains to be had by both the operator and labor. By the efficient application of modern equipment and improved mining methods the operator should gain by decreased costs, and labor may profit by receiving a share of these decreased costs.

Jan 1, 1950

By K. Adam

Grinding in steel mills adversely affects the flotation of pyrrhotite. The electrochemical nature of inter action between pyrrhotite and active metals was investigated by contacting pyrrhotite with platinum at different applied potentials. Flotation tests, scanning electron microscopy, Auger electron spectroscopy, and X-ray photoelectron spectroscopy were wed to examine the surface properties of pyrrhotite. The formation of hydroxide or oxide and sulfate species of iron through the oxygen reduction reaction at the cathodically polarized surface of pyrrhotite was shown to be the mechanism responsible for the reduced floatability of pyrrhotite.

Jan 1, 1985

By J. R. Thoenen

THE proper classification of mining methods has received the earnest study of many mining engineers and has resulted in much technical con-troversy, depending no doubt upon the point from which classification is viewed or the use to which it is put. So far as the writer is aware, the discussion has invariably centered around the classification of under-ground mining methods, and only superficial attention has been directed to surface methods. Volume 72, page 10, of the Institute TRANSACTIONS, presents such a classification, sponsored by the Mining Methods Committee of the Institute. A similar classification by Prof. Hugh P. Nicholson appeared in MINING AND METALLURGY in October, 1934. The two classifications are quite different in their treatment of underground methods but are identical in classifying surface methods, although Professor Nicholson does suggest possible further divisions for surface mining and admits that such subdivision is more difficult than appears at first. Surface subdivisions as given by these two authorities are as follows, showing that in spite of rearrangement the two classifications are identical:

Jan 1, 1935

(Members are urged to send in for this column any notes of interest concerning themselves or their fellow-members.) Members and guests who called at Institute headquarters during the period Jan. 10, 1916 to Feb. 10, 1916: William Rettie, Yonkers, N. Y. Wallace E. Pratt, Manila, P. I. R. V. Norris, Wilkesbarre, Pa. T. Skewes Saunders, El Oro, Mex. Fred MacCoy, El Oro, Mex. M. L. Requa, San Francisco, Cal. Reno H. Sales, Butte, Mont. R. W. Schultz, Ravenna, O. R. T. White, Batourn, Russia. H. J. Brown, Chester, Pa. David T. Day, Washington, D: C. A. M. Van Rensselaer, New Rochelle, N. Y. H. M. LaFollette, LaFollette, Tenn. Norman C. Stines, Russia. F. N. Speller, Pittsburgh, Pa. Howard R. Hughes, Houston, Tex. Robert W. Hunt, Chicago, Ill. C. F. Schnepp, Ridgefield Park, N. J. B. E. Fernow, Toronto, Ont., Can. George L. A. Thomson, Elizabeth, N. J. A. F. Bennett, New York City. Jasper T. Robertson, Chicago, Ill. J. C. Ralston, Spokane, Wash. J. B. Tyrrell, Toronto, Ont., Can. George J. Lyon, Schenectady, N. Y. H. G. Officer, New York Cty. Jesse C. Porter is now superintendent of the San Fernando Mine, Hoyo de Manicaragua, Santa Clara Province, Cuba.

Jan 3, 1916

By WM. HUFF WAGNER

Computations and allowances for mine depletion for Federal income tax purposes depend upon the meaning of certain terms in the pertinent provisions of section 114(b) 4 of the Internal Revenue Code. Unfortunately, but one of these terms is defined in the Code. Congress left it to the Commissioner to define the other terms in the Regulations. Even though the Commissioner, through his staff, labored long and earnestly to draft these definitions they have not been satisfactory to the mining industry, because the definitions in the Regulations and the interpretation placed thereon by the Commissioner do not state what the industry believes to be the clear and obvious intent of Congress. Consequently serious and prolonged disputes, unduly delaying the settlement of Federal tax returns involving percentage depletion deductions are continually arising between taxpayers and the Commissioner.

Jan 1, 1949

By ARCHIBALD DOUGLAS

AT various times during the past quarter century proposals have been made that the basic Federal mining law of 1872 be repealed or amended, and that in its place a new and simpler law be enacted to provide for the entry upon, working, and the taking up of claims on the unallotted Federal mining lands in our western states and in Alaska. Serious discussion and study have been given such proposals but little has resulted there from, except perhaps a lively interchange of opinion and the conclusion that though the Apex law of 1872 is in many ways highly unsatisfactory and frequently a fomenter of strife and trouble, it still bids fair to remain with us. Under this act a greater part of the non-ferrous mining industry of the United States has developed. With all its short-comings it is the legal bridge that has carried over the innumerable caravans of adventurers and prospectors who explored our mining frontiers. For without any amendments of substance this act has for fifty-eight years been the guide in the location of our western Federal mineral claims and has stood unchanged during the most important period of our mining history. While Federal and state acts and amendments have been ground out by thousands and tens -of thousands the mining act of 1872, with a :strange tenacity, has remained as constant as the Rock of Gibraltar, and under it states, mining districts, and local customs have developed different codes for its application but its fundamentals have been unaltered. "Use doth breed a habit in a man"; until now the application of the law of 1872 has become a second mining nature.

Jan 1, 1930

By AIME AIME

CONVENTION plans for the A.I.M.E. Regional Meeting to be held on the Minnesota Iron Range Aug. 12 to 1.5 are being completed to give the visiting member?s from all parts of the country a wide variety of technical and recreational features. High spots of the social events are the official dinner, dance, luncheon and golf: and of course, special provision is being, made for the entertainment of visiting ladies. The technical sessions will fit in with scheduled trips to view all phases of mining, beneficiation and transportation of iron ore. Men from the West and Southwest will find much of interest in the detail of the mining operations. A trip to the steel plant of the

Jan 1, 1941

By Clyde Williams

IF you would allow me some liberties, I would restate the title of this talk as "Scientific Research, Our Greatest Resource," because that title would represent more clearly a present-day conception of the metals and minerals situation. It is a subject worthy of careful consideration. Canada and the United States are so similar and interdependent in their national economies that, in the following discussion, examples of conditions in the United States may be interpreted to apply to Canada as well. Moreover, it is a striking fact that the per capita value of mineral production in Canada and the United States in 1940 was almost the same. Therefore, in the consideration of this subject, I have made no attempt to differentiate between the two countries. Consumption of the world's mineral resources in the last few decades. and particularly during World War II, has been so enormous as to require some form of magic to ensure the continued progress of civilization in the face of a diminishing supply of these resources which are so critically essential. As C. K. Leith pointed out, in 1941, indus-

Jan 1, 1947

By A. Hansson, G. E. Tardiff

WHILE it is generally known that cold-worked low-and medium-carbon steels exhibit substantial increases in tensile rupture ductility with increased deformation velocity172 (up to the von Karman limit), the observations for annealed or normalized steel do not permit simple generalization. Various investigators, for example, have reported both small increases1,3 and small decreases4,5' in rupture ductility with increased rates of deformation of normalized low-carbon steel. The purpose of the present note is to report on the dependence observed for strain-aged steel since preliminary work here indicates that strain aging results in the development of a consistent type of behavior that is understandable in the light of current knowledge of the lower yield dynamics for steels which deform inhomogeneously.6 This realization throws additional light on the influences responsible for the behavior of normalized steel. The results presented here were obtained for a 0.21 pct C, 0.012 pct N sheet (0.012 in. thick) steel which was received in a temper-rolled condition (approximately 3 pct reduction in thickness after process annealing); the as-received material had a spherodized structure with a ferritic grain size of ASTM 8. The material was selected for testing after 6 months room temperature aging, at which time the static lower yield and ultimate tensile strength measured 79 and 82 kpsi, respectively. ASTM 2-in. reduced section, 1/2-in.-wide specimens were used in smooth bar tests and 3/4-in.-wide specimens containing two 60-deg opposed edge notches (root radii = 0.002 in.) were used in notched bar tests. To facilitate strain measurement, the smooth bars were blued with ink and marked at 0.1-in. intervals along the gage length; the notched

Jan 1, 1968

By Ernest F. Burchard

MOST of the iron ore smelted in Alabama blast furnaces is mined within Alabama, although deposits in the neighboring States of Georgia and Tennessee may be drawn upon when occasion requires. Of the four commercial kinds of iron ore, the anhydrous ferric oxide, hematite (Fe2O3) ; the hydrous ferric oxide, mostly the type commonly known as limonite (2 Fe2O33H2O) ; the carbonate, siderite (FeCO3) ; and the magnetic oxide, magnetite (Fe:3O4) ; the first two are found in abundance in Alabama, the third in less than commercial quantities, and the fourth only rarely. Both the hematite and the hydroxide are found in somewhat different forms according to their geologic environment. The Red Mountain hematite, of Silurian age, that crops out in well¬defined beds for 1.50 miles northeast-southwest and 40 miles northwest-southeast is the predominant source of ore. Only a small part of this area carries ore of commercial value; Birmingham and Gadsden are now the only centers of production. The ore is of sedimentary origin, probably altered from vast deposits of greensand mixed with calcareous, fossiliferous. marine debris. Other types of hematite not vet mined commercially are in metamorphosed rocks-red ore in slates in Columbiana Mountain and specular hematite (gray ore) in quartzite in the Talladega Hills.

Jan 1, 1938

By JOHN R. SUMAN

TONIGHT I want to speak of the current problems and the postwar difficulties facing American industry. American industry has done an outstanding job in adjusting its operations to wartime necessity. The national income for 1942 was nearly $120,000,090,000 and of this outlay approximately $55,000,000,000 went for war material. The enormity of the expenditures for war material is indicated by the fact that the expenditures for war purposes alone were greater than the annual gross national income in the period 1931-34. This tremendous production job in turning out a record output of war products was accomplished by industry in spite of a large number of restraining and hampering influences, and I want to mention several of the more important problems.

Jan 1, 1943

By Leo H. Duriez, James V. Neuman

THE Bayard property of the united States Smelting Refining and Mining Company is in south central Grant County in southwestern New Mexico about fifteen miles east of Silver City and one mile west of Santa Rita. The present holdings cover a belt roughly one mile wide by ten miles long, lying west of, and adjacent to, the holdings of the American Smelting and Refining Co., Kennecott Copper Corp., Empire Zinc Co., and Peru Mining Co. The area extends from the village of Bayard on the south to a point three miles northeast of Fierro. The property is a part of the well-known Central mining district which has been New Mexico's leading copper-zinc producer for many years. The property is segregated into three sections, the Bullfrog, Hanover Bessemer, and the Shingle Canyon sections. Of these, the Bullfrog section covers the area between the towns of Bayard and Hanover and includes the Bullfrog No. 1, Bullfrog No. 2, Slate, Hobo,

Jan 1, 1948

By George Lehman

THE Inspiration Consolidated Copper Co. had an orebody at Miami, Ariz., of close to 100,000,000 tons of low-grade copper ore, and the method of mining this ore most profitably was of great importance. The selection of a method was practically limited to a "top-slicing," a "shrinkage-stope" or a "caving" method. The "top-slicing" method would give a high extraction of the developed ore, at a high mining cost, and the ?shrinkage-stope" or "caving" methods ) a lower extraction of, the developed ore, at a lower mining cost. ORE-DRAWING TESTS To decide on the method to be used it was necessary to know about what extraction of the ore could be obtained by the "shrinkage-stope" or "caving" methods. As no definite information regarding the question was available at the time, C. E. Mills, the general manager, thought that some information could be obtained by experimenting in drawing ore, covered with capping, from an experimental box. Some work had already been done along these lines by W. C. Browning for the Inspiration Copper Co. and by myself for the Live Oak Development Co. The idea was to represent as nearly as possible, in the experimental box, the conditions within an area of caved stopes of caved ore all ready for drawing. That is, the area was supposed to represent a semibroken mass with the capping above it in the same condition and ready to follow the ore downward as it was drawn out of the chutes under the ore. To represent the above condition, in the experimental box, crushed ore from the mine was placed in it to a given height, and red barren capping from the mine was placed on top of the ore.

Jan 9, 1916

By Charles Will Wright

MINERAL production in almost all European countries suffered a sharp setback because of the war. Plants were damaged, transportation facilities disrupted, and labor dispersed and demoralized. Since the war, due to lack of confidence and economic stability, there has been little incentive to rebuild and expand the mineral industries even though a big demand at high prices exists for mineral products. Most mining and metallurgical companies in Europe hesitate to invest their capital because of the tendency towards nationalizing industry, high taxes, and low output of labor, as well as the deficiency of mine supplies and equipment within their countries. In short, they do not have faith in the future, and for these same reasons and fears most of the mining companies in America will not risk capital investment in Europe. In Europe, including the United Kingdom, free enterprise has been losing ground and as a result the foundation of their economic welfare is being undermined. American mining interests willing to take the initiative could help in counteracting this influence if a way were found for them to co-operate with the European producer without too great a risk.

Jan 1, 1948

By J. R. Dunn

Planning quarry operations and control of the quality of rock materials at Hudson Cement Co. at East Kingston, N. Y., are special problems because of multiple uses for the stone and the great structural complexity of the rocks. Problems have been largely solved by detailed geologic work. These geologic studies have paid dividends in long and short range planning, in assessment of reserves, in vastly reduced cost of chemical analyses, and in reduced drilling costs. Limestones of the Hudson Valley outcrop along the Hudson River from Albany to Kingston. Old established cement companies are located just south of Catskill and just east and southeast of Hudson, N. Y. The new Atlantic Cement plant is being constructed at Ravena. Hudson Cement located at East Kingston, is a newcomer and is closest to the New York metropolitan area (Plate I).

Jan 11, 1961

By R. C. Ernrnons, Ray Wilcox

RECENTLY completed experimental work, carried out in the department of geology at the University of Wisconsin, aiming at a prevention of silicosis in industry has been reported in the American Mineralogist. A vast amount of work on silicosis has been reported in the literature, the clinical aspects having been especially well covered. A host of critical observations have been made on the variations in the nature of the silicosis problem in different environments, and a great deal of valuable experimental work has helped to clarify these observations. At present a greater amount of information of a critical sort is available than ever before, which affords a more sound basis for interpretive thought. It has been observed in industry that essentially pure silica dust gives rise to silicosis. Jones would modify this conclusion to place the responsibility on sericite, a silicate mineral present in the siliceous dust. Material such as granite dust, which carries a high free silica (quartz) content, is also a silicosis hazard. But sericite, too, is usually present in granite. In general it is widely believed that silicosis is caused by the presence in the lung of silicic acid regardless of the source. This view is adopted here.

Jan 1, 1937

By Harold Vance

EMPLOYERS of engineers have not always been satisfied with the training that young graduates have received in the conventional four-year course. Specifically, employers of petroleum engineers for a number of years have believed that a four-year course does not allow sufficient time for the student to secure a fundamental engineering background plus the fundamentals of petroleum engineering. A group of California employers went so far as to set up a type of curriculum for a petroleum-engineering course, which was based on four years of undergraduate work and one year of graduate work, with most of the petroleum-engineering courses included in the graduate year.

Jan 1, 1944