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By Richard Miller

WORK was undertaken two years ago at the Hammond Laboratory for the purpose of determining the magnitude of the elastic range in single crystals of pure metals by means of creep tests, the assumption being made that if a true elastic range exists, the elastic limit represents the maximum stress for no creep. A sensitive extensometer was constructed, and creep tests were made on zinc single crystals at a variety of loads and temperatures1. It was soon discovered that there is tip measurable elastic limit in ductile zinc single crystals at, or above, room temperature. The inference that pure metallic single crystals may not possess a definite elastic range was not justified, however, since zinc had been tested in creep only above its recrystallization temperature, and several investiga-tors2,3,4 had already shown that above the recrystallization temperature polycrystalline metals will flow under very small stresses, while below that temperature stresses of a much larger magnitude are required. For that reason, it was decided to extend the study of the elastic limit to other metals having a higher recrystallization temperature than zinc. Aluminum and silver were selected, because of the ease of obtaining pure materials and of preparing large single crystals, and because the crystallo-graphic glide system of these metals is well known. Owing to the limited time available, the elastic range was investigated by slow tensile tests rather than by creep tests.

Jan 1, 1937

By R. V. Ramani, T. S. Kovach

In many instances, the actual production from a longwall face does not equal the planned capacity. General problem areas that have been identified include face length and panel depth, face area and gate entry roof support, face conveyor and shearer wear, outby haulage system failures, number of entries in longwall gate development, and longwall move time. The performance of a longwall face is totally dependent on the interaction of these and other factors. To explore fully these interactions, a systems analysis of longwalls has been performed. In this paper, the systems approach, the factors considered in the analysis, and the results of the analysis are presented.

Jan 1, 1985

By C. K. Rose, J. H. East

Proved oil shale reserves in the Green River formation in Colorado, Utah, and Wyoming dwarf present U. S. petroleum resources. Indications are that the appetite for petroleum products will continue to grow and that this potential source of liquid fuels and related byproducts cannot be disregarded. As a part of its synthetic fuels program, the U. S. Bureau of Mines has opened a mine in the richer beds on the naval oil shale reserves. In addition to supplying material for retorting and refining studies, the development of methods, procedures, and equipment for mining oil shale on a large-scale commercial basis is of the greatest importance.

Oct 1, 1955

By Yoshihiko Shimazaki, Hokuichiro Ohmachi

Mineral resources of Japan are remarkably characterized by the diverse variety of ores. Seventeen kinds of metallic ores are produced in Japan from approximately 175 mines, but the country is becoming increasingly dependent on imported ores, and 23 ores such as bauxite, nickel and platinum are not produced domestically. Self-sufficiency of non-metallic minerals is higher than metallic ores. Twenty three non-metallic minerals such as fire clay, pyrophyllite dolomite, and limestone are produced from about 1264 mines. About 22 minerals such as graphite, asbestos, fluorite, and phosphorites are not produced in the country. One of the major concerns of Japan is raise the self-sufficiency of raw materials. The result of the analysis of the mineral potential of Japan in relation to possible future domestic supply and is reported.

Jan 1, 1976

By F. J. Darnell

SINGLE crystals of a-titanium are difficult to obtain because of the phase transformation at 882 °C in which the structure changes from the high-temperature body-centered structure ß to the low-temperature hexagonal close-packed structure a. Preparation of single crystals of a-titanium has previously been accomplished by a strain-anneal method which takes several days and is not generally reproducible. Single crystals as large as 5 mm

Jan 1, 1959

By Charles H. Moore

When lime and magnesia are used as fluxes in the smelting of titaniferous ores fluid, digestible slags low in iron oxide and high in titanium dioxide are produced. The mineral phases present in such slags are (Fe,Mg)O.2TiO2, CaTiO3, and minor amounts of silicate glass (or its devitrification products). The flux additions are added to the ore in relative amounts to crystallize a ratio of (Fe,Mg)O.2TiO2 to CaTiO2, of near the eutectic proportions of 60 pct (Fe,Mg)0.2TiO2 and 40 pct CaTiO3. FeO-Ti02 (ilmenite) remains present in the slag until the FeO content is reduced to approximately 8 pct. Op- timum slag composition is obtained by reducing the FeO content to between 2 and 6 pct. Continued reduction shifts he (Fe,Mg) 0.2Ti02 to oxygen deficient structures classified as MgTi30e and MgTi204. Further reduction yields titanium oxycarbides and freezes the melts.

Jan 1, 1949

By Lucien Eaton

IN anticipation of a shortage of labor for hand-tram-ming at the Cliffs shaft mine of the Cleveland-Cliffs Iron Co. at Ishpeming, Mich., early in 1923 three 4-ton Goodman storage-battery locomotives, equipped with Edison batteries, were purchased. Storage-battery locomotives were chosen for this work because the expense and time required to put up trolley-wire and to bond the rails of the complicated system of tracks on the levels, where the locomotives were to be used, would not have been warranted by the amount of ,ore to be handled. The only changes in the tracks necessary for storage-battery locomotives were new switches and extra ties and braces on curves. The tracks were 24-in. gage, and were laid with 20-lb. rail. Edison batteries were chosen, because it was desired to charge the batteries from the trolley circuit already, in the mine, and this would have been impracticable with lead batteries. Each locomotive is equipped with 126 A-4 Edison cells, which are charged in series from the 240-volt trolley circuit while the trolley locomotives are running; and are discharged in parallel in two banks of 63 cells each. These locomotives were so successful that later 5 smaller locomotives, weighing 11/2 tons each, were pur-chased for use e with cars that are filled by hand and on levels where the amount of ore handled is small. These locomotives, built by the Geo. D. Whitcomb Co. of Rochelle, Ill., are equipped with batteries of 40 A-4 Edison cells each, the cells being the same as those, on the larger locomotives. They are charged from mer-curial-are rectifiers. These locomotives are operated by the trammers themselves, and have not special oper-ators like the larger machines. The trammers are all young men of American birth, and take quickly to the operation of machinery, and the simplicity of the con-trol on these locomotives has made special training unnecessary. A survey of the results was made by the A. C. Nielsen So., an excerpt from which follows: Eight Edison-equipped battery locomotives are now in use at an Ishpeming mine of the Cleveland-. Cliffs Iron Co. This equipment was installed to take the place of men who formerly pushed loaded cars by hand. Results have been very satisfactory and the de-pendable, trouble-free operation of the Edison batteries is considered to have been an important factor in the effectiveness of the new hauling method.

Jan 3, 1927

By Paul E. Nilles

For every single BOF heat, the steelmaker must control the refining operation in order to satisfy at turndown the following conditions : - to reach the correct steel analysis (C, S, P, ...) in the shortest time possible, i.e. without reblow; - to maintain the temperature of the metal in a narrow range; - to produce the optimum steel weight. It is obvious that during refining limited time and scarce information are available and only very few corrective actions can be taken. For this reason, it is of the greatest importance to facilitate the control of the BOF process by taking adequate measures before and during charging of the converter. These are : - the availability of accurate and reliable equipments for the classical measurements, 5.e. weights, temperatures, flow-rates, analyses, etc... - the operation of an optimal charge calculation model which takes into account all information concerning the preceeding heats and the charged materials. '

Jan 1, 1972

By M. E. Wadsworth

The region about the south shore of Lake Superior is to geologists one of the most interesting districts of the United States, embracing as it does, in a limited area, old crystalline rocks, together with forms that are almost in their original condition of a beach sand and mud. In this region was first established the base of the geological column, the Azoic (" without life") System of Foster and Whitney, or the Archæan (" the beginning ") of Dana. Overlying this system are found the sandstones and limestones of the Paleozoic (" ancient life "), and their associated lava-flows (Algonkian ?). These systems possess a strong economic interest, owing to the stores of iron in the Azoic and of copper in the Paleozoic or Eozoic of this district, which forms one of the most important mining regions in America. The geology of this section is so difficult and complicated that, in its general discussion, perhaps no proposition can be stated concerning any portion of it to which exceptions cannot be taken. Indeed, out of the general discussion of different points comes in time the truth, and various geologists, even now, are working over this region in the endeavor to arrive at some consensus, or at least to determine upon what points they can agree, and upon what points difference of opinion will have to exist between them at present, until further evidence can be obtained. The writer will endeavor to give in a brief form that which appears to him at present to be the most correct statement of the geological structure of the region, admitting that from time to time, as more complete evidence shall be obtained, he expects to change his views in the future, as he has done in the past, if that evidence shall cause him to believe that he has been mistaken.

Jan 1, 1898

By Dr. O’Neil Thomas J., Donald W. Gentry

It was a western truism that more money was made from selling mines than from buying them, just as it was accepted that many a good mine had been spoiled by working it. from R. E. White, "The Mining Town," Alta California August 18,1873 INTRODUCTION One of the most important aspects of mineral enterprises of US corporations is the influence of the depletion allowance on cash flow. This allowance permits mineral producers to claim sizable federal income tax deductions not available to other industries, and these deductions significantly increase cash flows in mining. In the past several years the minerals depletion allowance has come under increasingly heavy fire from many sectors as a tax loophole that deprives the federal government of large amounts of revenue. One estimate of the loss of tax dollars in 1968 was $2.25 billion due to depletion deductions and intangible expenses in the oil industry. Largely on the basis of such arguments, the Tax Reform Act of 1969 reduced percentage depletion rates for a number of minerals, and the Tax Reduction Act of 1975 totally eliminated statutory depletion for most oil and gas. In regard to percentage depletion for hard minerals, the federal government has estimated its resulting loss of revenue at $1.75 billion for 1980. The TEFRA legislation of 1982 further reduced the statutory depletion allowance available to iron ore, coal, and lignite beginning in 1984. Thus, it is clear that minerals engineers and managers should have a thorough knowledge of the origin, evolution, justification, and computational procedures relating to the depletion allowance. ORIGIN AND EVOLUTION OF THE DEPLETION ALLOWANCE

Jan 1, 1984

The Fifth Annual National Exposition of Chemical Industries will be held in Chicago at the Coliseum and First Regiment Armory during the week of Sept. 22. It was decided to hold the exposition in Chicago, this year, for two reasons: The U. S. Army commandeered the Grand Central Palace Exposition Building in New York, immediately on the close of the last exposition and converted it into a receiving hospital, the use for which is now, happily, nearly ceased; and it was thought that the Exposition would succeed in bringing about a greater development of chemical industries in the Chicago district and the adjoining states. The Advisory Committee of the Exposition consists of: Charles H. Herty, Chairman, Editor Journal of Industrial and Engineering Chemistry; Raymond F. Bacon, Director, Mellon Institute; L. H. Baekeland, Member Naval Consulting Board; W. D. Bancroft, President, American Electrochemical Society; Henry B. Faber, Industrial Filtration Corpn.; Ellwood Hendrick, President, The Chemists' Club; Bernard C. Hesse, Chemist, General Chemical Co.; A. D. Little, President, Arthur D. Little Inc.; Wm. H. Nichols, President, American Chemical Society; R. P. Perry, Vice-president, The Barrett Co.; H. C. Parmelee, Editor Chemical &; Metallurgical Engineering, G. W. Thompson, President, American Institute of Chemical Engineers; T. B. Wagner, Vice-president, U. S. Food Products Corpn.; M. C. Whitaker, President, U. S. Industrial Chemical Co.; and Charles F. Roth and Fred W. Payne. There is also added a special Chicago committee consisting of L. V. Redman, W. D. Richardson, A. V. H. Mory, Carl S. Minor, F. W. Willard, and Wm. Hoskins; the managers, as in the past, are Charles F. Roth and Fred W. Payne.

Jan 6, 1919

This excellent, concise paper by Dr. Iwasaki on the principles of selective flocculation for iron ores discusses many of the principles and problems which have occurred in our bench and pilot plant test-work. The use of sodium tripolyphosphate in combination with sodium silicate as a dispersant is very effective. However, this may cause a problem with the environmental groups as phosphorous is a nutrient. We have also established that the lower the Ca level in the pulp solutions the greater the dispersion. We have found that ores from the same geological strata, having the same general mineralogy and iron content will sometimes have widely different degrees of dispersion. There was-no difference in the gross mineralogy but the solubility of the Ca and SO ions was much less in the ores most easily dispersed. Research efforts should be directed towards a more practical means which would more easily enable one to predict the amount of dispersant required for the various ores. With regard to water quality we have found that waters having higher contents of SO4 and C1 ions hinder dispersion. This could be a method of controlling too much dispersion by the addition of sulfate or chloride ions. This would require further investigation. We have had no trouble with agitation speeds of up to 925 rpm in conditioning starch with the dispersed pulp prior to selective flocculation. We have found about 0.3Lb/LT of starch to be sufficient for selective flocculation on our ores. The increasing of the starch to 1.25Lb/LT has had no effect on the metallurgy of the selective floccula-

Jan 1, 1979

By J. L. Leland Myer

Some of the early experiments on the oxidation temperature of coal1 were undertaken in England in connection with a study of self-heating, or spontaneous combustion. It was then suspected that coals with low oxidation temperature were most likely to ignite by self-heating, but further experiments showed that many additional factors were involved. The oxidation temperature has importance as a physical property or characteristic of the coal. While only a few of the physical properties have been studied, they appear to have basic significance2 in the ultimate classification of all coals. When reliable data become available on the oxidation temperatures, as determined by standard and adequate methods, it should provide an additional basis for classification and comparative evaluation. Oxidation Temperature Defined For such a heterogeneous substance as coal is known to be, no simple definition of oxidation temperature can be established on a theoretical basis. If coals were homogeneous and of simpler structure, the accepted definition of "ignition temperature " as applied to simple gaseous mixtures might be adopted; that is, the temperature at which self-heating of the mixture sets in. But most coals self-heat slightly even at storage temperature, as evidenced by spontaneous combustion, and the definition for gases cannot be applied to coals with any exactness. By subjecting coals to suitable experimental conditions various oxidation characteristics can be obtained and examined for critical or significant stages of the oxidation process. Oxidation temperature itself must then be defined on the basis of such experimental results. Experimental Methods Attempts to determine critical points in the temperature functions of coal undergoing oxidation have resulted in the following experimental methods:

Jan 1, 1932

By J. B. Campbell, V. V. Valleroy, B. T. Willman, L. W. Powers

A steam drive of heavy oil was field tested in a shallow, low oil-saturation formation near Deerfield, Mo. The pilot was conducted in the Warner formation, a sandstone containing an 18' API oil having 1,000-cp viscosity at the 60F origind reservoir temperature. The formation war at a depth of 160 ft. Steam was injected into nine input wells arranged in an array of inverted five-spot patterns. In the completely confined center pattern, 14 temperature observation wells were installed to obtain thermal data and observe test progress. Late in the test, slugs of ammonia were injected to trace the flow paths of injected fluids. From the test area about 7,000 bbl of oil were produced. Data were obtained on areal and vertical temperature distribution, steam front advance, reservoir fluid movement and terminal saturations. This field test of a steam drive (I) demonstrated the feasibility of the method, (2) confirmed that the low residual oil saturations observed in the laboratory are obtained in the steam-swept region in the field and (3) provided recovery and conformance data for one set of field conditions. INTRODUCTION The Deerfield steam drive pilot test was conducted in a shallow sandstone containing 1,000-cp oil. The venture was undertaken cooperatively by the research and production departments of Carter Oil Co., which organizations have since been consolidated into Esso Production Research Co. and Humble Oil & Refining Co.. respectively. The production department was interested in steam injection at Deerfield because it appeared to be the most promising method of commercially producing this heavy oil deposit. The research department was interested in applying the new recovery method and in evaluating its performance in the field. At the time the test was begun, the initial oil saturation was not well known. Subsequent air coring and early pilot results confirmed that there was too little oil in place for profitable commercial exploitation by steam. Pilot termination at that time, however, would have been premature for evaluating field performance of the process, and the tert was continued to obtain additional data on steam injection as a recovery method. The test was located in Vernon County, Mo., about 10 miles north of the town of Deerfield and only a few miles from the Kansas border. The pilot site was selected as typical of the area. The location represented neither the highest nor the lowest oil saturation region in the acreage under lease in 1954. The steam drive was conducted in the Warner sandstone of Lower Pennsylvanian age. At the test site the top of the Warner occurs at about 160 ft subsurface and the formation is a fine- to medium-grained micaceous sandstone that dips gently to the northwest at the rate of 12 to 15 ft/ mile. A cross-section and permeability profile of the test location are shown in Fig. 1. At the pilot location the average total thickness of the Warner formation is about 43 ft, but the effective thickness for steam drive is 26 ft. Two distinct types of hydrocarbon saturation are apparent. The lower portion of the total sand, averaging about 17 ft thick, contains a very heavy asphaltic material that will not flow under the influence of a steam drive. This bottom interval, referred to as a dead oil residue, was not considered as part of the net sand undergoing steam exploitation. The initial formation and fluid properties of the upper 26 ft in the test area are summarized in Table 1, and variation of oil viscosity with temperature is shown in Fig. 2. Imbibition tests on preserved core samples taken at the end of the pilot test showed that the Warner sandstone was then neutral or slightly water-wet. Initially, the reservoir may have been strongly water-wet as indicated by low relative permeability to water during both water injection testing and early steam injection. PRIOR HISTORY Initial production tests of wells at the pilot site produced water with only a faint show of oil. No gas was produced except at Well 7-W in the pilot area and at another well about 1/3 mile northeast of the pilot. Prior to the start of the steam drive, a two-well water injection test and a two-well air injection test were conducted. No oil was produced by either. Water was pumped into Well I-W in the northeast corner of the pilot area with simultaneous production from Well 1 (Fig. 3). The air-injection tat was run at input Well 9-W and its offset, Well 2, in the southwest corner. Air and water injectivities were about the same when corrected for viscosity and pressure differences.

By John V. Beall

The "free form life," The Wall Street Jourlzal called it. That is what the young people are practicing who have dropped out after successfully completing a college education. The ones described were first-rate students who did not embark on careers but instead selected such nonintellectual jobs as delivering mail, short- order cooking and the like. We couldn't help thinking that it wasn't so long ago, that we had the ideal setup in mining for folks of this persuasion when most college grads were started out as muckers. Actually there isn't much new in this business of doing your own thing. Being a type that takes westerns seriously, we jumped at the chance to catch the rerun of the wide-screen flick "How the West Was Won." There was Jimmie Stewart playing the part of the mountain man, with a canoe full of furs going east down river. Coming west up river, is a settler with his daughters. This mountain man had on his fringed buckskins, his two-year growth of long hair and a tremendous thirst. He had been doing his thing and planned to keep right on doing it. However, one of the pretty settler girls had other ideas. The same fate probably awaits today's individualistic youths.

Jan 1, 1970

By R. P. Rothwell

Instruction by correspondence is certainly one of the most important and useful of modern educational methods. The paper on the " Scranton International Schools," by Prof. Stoek (Buffalo meeting, October, 1898),* gives an elaborate description of a single private enterprise in this direction, ignoring all others, and cannot be said to present a fair or impartial view of

Jan 1, 1900

By H. Jehn

The high-temperature oxidation of Pt metals results' in the formation of volatile oxides. The evaporation of which considerably increases the metal losses in oxygen-containing atmospheres when compared with high-vacuum or inert-atomosphere conditions. The paper describes gravimetric investigations carried out to determine the metal losses of polycrystalline samples of Ru, together with earlier studies on Ir and Pt at oxygen pressures of 10-3 to 1000 mbar and temperatures > 1000 °C. A strong pressure and temperature dependence is noted. Preliminary results of the oxidation of Pd are reported, too (665 mbar 02, 1100-1300 °C). The oxidation mechanism is discussed and the oxidation rates of Ru, Pd, Ir and Pt are compared with those of the other Pt metals Rh and 0s and of refractory metals.

Jan 1, 1984

By C. S. Barrett, D. B. Masson

Martensitic transformations have been found in AgCd both upon cold-working at room temperature and cooling to lower temperatures. The crystal structures of the transformation products were found to be close-packed hexagonal in the first case and or-thorhombic in the latter. The transformation characteristics also were studied. Similar treatment of AuZn alloys failed to yield any transformation. THE literature on martensitic transformations of body-centered cubic metals and alloys indicates widespread instability of this structure at low temperatures, a tendency which merits further study. The body-centered cubic ß-phase of CuZn, for example, when it contained less than 42 wt pct Zn, was found by Greninger and Mooradian' and others' to transform on cooling to subzero temperatures to a phase that was tentatively considered to be tetragonal. Further work by Massalski and Barrett" demonstrated that cold work at low temperatures causes a partial transformation of ß CuZn of higher Zn content. The structures of the strain-induced transformation products were found to be different from those induced by simple cooling. Another well-known martensitic transformation among body-centered cubic phases is that of ß AuCd, first studied with X-rays by Olander,' then very thoroughly by Chang and Read.5,6 Here again transformation was found to occur both as a result of cooling and of strain. The alkali metals Li and Na, as well as certain Li-Mg alloys, also undergo transformation from their normal body-centered cubic structure, both on cooling and on cold-working. The phase AgCd, the subject of the present report, should be expected to behave quite similarly to CuZn for a number of reasons. It is the chemical analogue of CuZn, silver being directly below copper and cadmium directly below zinc in the periodic table. The size factors (percent difference in size) of the atoms, possibly a consideration in the stability of the ß-phases, are +3.1 in AgCd and + 4.2 in CuZn. Likewise the relative electronegativities of the two pairs of metals are about the same, CuZn possessing an electronegativity difference of 1.0 and AgCd one of 0.8. These values are from a table of electronegativities given by Darken and Gurry." The phase diagrams of the two systems around 50 atomic percent are similar, both possessing a disordered body-centered cubic phase, ß, at high temperatures and an ordered bcc phase, ß, at room temperature; however, the ß and ß' phases of AgCd are separated by a hexagonal phase, [, stable in the range 220-440oC, which has no analogue in CuZn. There has been confusion in the literature as to the structures of the ß' and [-phases. The phase diagram in the ASM handbook'" has the structures of the two phases interchanged; however, Hansen" reports the correct relative positions and Muldawer" verified that ß', the low-temperature phase, is body-centered cubic. Work by the present authors also

Jan 1, 1959

By Charles M. Cooley

A NOTED Prospector Passes-Stories of the grizzled old prospector that discovered what turned out to be a famous and highly profitable mine, only to die in poverty through the shenanigans of "the Interests," are legion. It is pleasant, therefore, to be able to report that the discoverer of one of Canada's most famous mines was more fortunate.

Jan 7, 1953

By F. Weston Starratt

The opening of a new large-scale beneficiation plant is always news, but the start-up of Cleveland-Cliffs Iron Co.'s Eagle Mills near Ishpeming in Michigan's Upper Peninsula early in October is of particular interest because of the completely different type of operation being carried on at this plant. The ore boat which left Marquette, Mich. on the 3rd of October bound for the plant of Wisconsin Steel Division of International Harvester, not only carried the first output of this new mill, but also carried the first agglomerate made from the Upper Peninsula's jasper ore, the first commercial output from an updraft traveling-grate furnace, and the first large-scale commercial application of the balling disk, also called the flying saucer, to the agglomeration of an iron flotation concentrate.

Nov 1, 1956