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By G. C. Stone

At the conclusion of my paper on the same subject read at the Boston meeting of the Institute, I offered to send some of sample No. 2 to any chemist who wished to analyze it. Eight chemists wrote to me for samples; so far I have received results from five. I give these results in a table (on the following page), together with the results previously obtained: As to the chemists and their methods : K is an iron-works chemist whom I only know by correspondence; lie writes: "No. 27(13.64) was obtained by the method I generally use, as follows : Dissolve 0.8 grams spiegel in hydrochloric acid and a little potassium chlorate, in a half-liter flask. Boil off most of the acid, add ammonia in slight excess, redissolve in acetic acid, using rather more than is really necessary, and then add 8 or 10 grams of sodium acetate and make up to the mark with warm water. Boil hard for fifteen minutes, then allow to settle (cool?), until the liquid reaches the mark, and withdraw 300 C.C. of the nearly clear liquid. Add to this an excess of hydrochloric acid, evaporate to dryness, take up with hydrochloric acid and water, and separate the iron by two precipitations with ammonia (I have often tested the ferric hydrate for manganese, but have never found any, if the separation by ammonia was properly made). Finally, precipitate the manganese as phosphate." Nos. 28, 29 (13.35, 13.07) were by Ford's method." No. 30 (13.50) was by Troilus's method He writes, " I may add the results are quite as good as I expected, although for any element except manganese, they are not close enough for anything like accurate work." L is a firm of commercial chemists of large experience who have made a specialty of iron work. Their method is as follows : Dissolve

Jan 1, 1884

By Theron Wasson

Michigan produced 16,637,000 bbl. in 1937. This makes it a record year in the history of Michigan's oil industry. During the year 953 wells were completed; 779 within the limits of established fields and 174 wildcats; 616 new oil wells, 68 gas wells and 269 dry holes. Table 1 has been arranged in alphabetical order of field names. Production figures for 1936 have been corrected because December figures were estimated. In this year's summary, December production is based on actual reports. The Leaton and Mt. Pleasant fields have been re-defined. Mt. Pleasant production north of the south line of Denver township, Isabella County, has been included with Leaton in accordance with usual practice in Michigan. The locations of fields discovered since the last map was published1 are shown in Fig. 1. Activity during 1937 Buckeye Field.—The Buckeye field of Gladwin County was the center of greatest activity during the year and was responsible for the increase of 4,700,000 bbl. over the state total for 1936. Buckeye produced 6,428,-000 bbl. in 1937. In this field 328 producing wells were completed during the year—over one-half the oil producers drilled in the state. Buckeye was subject to voluntary and cooperative proration from April 1 to the end of the year. Other pools of the state were not prorated. The new production at Buckeye is from porous Dundee limestone of Devonian age, similar to the older fields. Other New Fields.—The Sherman field was second in importance as a source of new production, with a total of 1,532,000 bbl. Salem township, Allegan County, on the southwest side of the Michigan Basin, was developed during the year. Production at Salem is from the Traverse limestone at a depth of 1600 ft., and 52 producing wells have been drilled in this pool. Other active pools were Clayton and Adams townships, Arenac County. The Bentley pool, discovered in October 1937 southeast of

Jan 1, 1938

By F. R. Hensel

The present study was made to determine the laws governing the formation of the primary? crystal structure during solidification. Most of the experiments were carried out on chill castings, but from the resiilts it will be possible to draw certain conclusions as far as sand castings are concerned. It is necessary to discuss first a number of theories, which are generally adopted for explaining the structure of an ingot. Usually, the structure of an ingot consists of the following three zones (Fig. 1): (1) a chill layer of small at-random oriented crystals; (2) a layer of columnar crystals; (3) a zone of equiaxed crystals. The tensile properties of the chill layer and the equiaxed range are usually much better than in the columnar range, particularly the planes that are formed by the columnar crystals growing from two sides at right angles have low tensile properties. This is one of the reasons why columnar crystals in ingot structures are undesirable.

Jan 1, 1937

By John Birkinbine

Since the presentation of the paper upon " The Concentration of Iron-Ore," which the writer, associated with Mr. Thomas A. Edison, read before the Institute in February, 1889 (Transactions, vol. xvii., 728-744), much time and money have been devoted to applications of various forms of concentrating apparatus, particularly in treating magnetic iron-ores. An indication of the interest which has been developed is shown in the four payers presented at and printed in advance for this meeting." The question, does magnetic concentration pay? is now being discussed by many owners of magnetite deposits, and affirmative answers can be readily obtained from patentees or agents of special machinery, while ultra-conservatism may give a prompt negative reply, based mainly upon the apparent impracticability of handling, crushing, sizing and separating large quantities of ore, and upon the generally

Jan 1, 1891

By Lester Tarnopol, Ralph Hultgren

A considerable interest in the subject of superlattices has been manifested by many papers and reviews that have recently appeared, both in physical and metallurgical publications. This interest is due largely to the apparent simplicity of the ordering process, which permits the explanation of many phenomena on the basis of elementary theory. Moreover, ordering may cause important changes in the physical properties of alloys. In this paper, we shall discuss the causes of superlattices in terms of simple properties of the elements that give rise to them, together with a series of experiments performed to test our conclusions. Evidence is presented that in some cases the process of ordering is more complex than might be supposed. While the different species of atoms are usually found in random positions in alloy lattices, in some cases unlike atoms tend to be nearest neighbors. Bethe's1 "order of neighbors" is a statistical measure of thib tendency. At suitable compositions it is possible for atoms in large regions to be regularly arranged, which causes superlattice lines to appear. in X-ray diffraction patterns. Bragg and Williams2 haw dealt with this "long-distance order" in their fundamental work 011 superlattices. Excellent discussions of superlattices are to be found in current reviews TheRmodynamic Considerations Thcrmal vibration tends to destroy order. The magnitude of the effect can be determined from the entropy of mixing, which is calculate from first principles. Since the ordered state has the lower entropy, it must also have a lower internal energy to be stable at any temperature. The difference in internal energy determines the critical temperature at which long-distance order disappears. According to the, theory of Bragg and Williams,~

Jan 1, 1939

By J. T. Crawford

THE purpose of this paper is to present some data and comparisons regarding three types of Rheolaveur plants washing bituminous coal from the Pittsburgh seam. It deals only with the sections that handle coarse coal. The Rheolaveur system consists of launders or troughs in which coal and its associated impurities are conveyed by water. The impurities, being heavier than the coal, settle toward the bottoms of the launders and are drawn off through specially designed openings called Rheo boxes. Fundamentally, each plant consists of straight-sided, flat-bottomed launders of varying width and length, each launder equipped with one or more Rheo boxes for the removal of high-gravity fractions of the feed that are undesirable in the cleaned coal. Each launder has at least two longitudinal sections, the first with a slope of from 1 1/2 to 4 in. per foot of length, called the classification section. The single-box launder has a classification section followed by a washing section ahead of the box. A two-box launder is a single-box launder followed by a washing section and a second box. The slope of the washing section between the first and second boxes is determined to some extent by tonnage. At the end of the classification section, which may vary from 8 to 15 ft. in length, the slope abruptly flattens out to a slope of from ½ to 1 in. per foot of length. This flatter section of the launder, called the washing section, may vary from a few feet, in a single-box launder, to 15 ft., in a two-box launder.

Jan 1, 1938

By W. L. Kendrick

At Henderson, Nev., Manganese Inc. is mining by open pit methods a low grade manganese ore averaging 21 pct Mn, concentrating it to 42 pct by flotation, and agglomerating it to produce nodules of metallurgical grade-about 48 pct Mn. The striking aspect of the whole operation, and one that has considerable effect on nodulizing, is the use of approximately 250 lb of reagent per ton of mill feed. For many years rotary kilns have been used for drying, calcining, clinkering cement and other products, and burning lime. Their use for nodulizing or agglomerating a metallic ore is new-first reported in this country in 1904, when a small rotary kiln at South Chicago was employed to nodulize flue dust from a blast furnace. After a short time this process was replaced by sintering.

Nov 1, 1956

By Charles H. Jacoby, Leo E. Read

IN diamond coring salt beds to evaluate deposits, special techniques are applied to standard slim hole drilling to obtain a representative sample of the water soluble sodium chloride. Industrial consumers generally require a run-of-the-mine material of 98.0 pct sodium chloride. Since no commercial beneficiation has yet been devised to upgrade the lower quality salt beds, the only processing is crushing and screening to the size required by the customer. Coring salt sections has recently become important not only in dry mining, but also in the development of brine cavities by hydraulic fracturing and the formation of jugs for storing liquid petroleum products. Drilling Fluid: The fluid used in coring salt beds in New York, Ohio, and Michigan is a thoroughly saturated brine made from 3.0 lb rock salt per gal of make-up water. This mined rock salt, -4 mesh +10 mesh, is dissolved in a lixator, a double-bottomed cone hopper that turns fresh water to fully saturated brine.

Jan 5, 1957

By Charles H. Doolittle, Royal P. Jarvis

The following notes are contributed, not with the idea of offering a complete history of the development of this very important process as applied to the Leadville district, but with the hope that the practice, as it was carried out in the Bi-Metallic Smelter, may still be of interest to others. The Bi-Metallic Smelter, at Leadville, Colo., was the first to make a commercial success of the process described in the following pages, which consisted essentially of smelting raw silver- and copper-bearing sulphide ores in blast-furnaces to form a matte, which was generally re-smelted with siliceous ores for a second high-grade matte. Robert Sticht, in his excellent monograph on the subject,' has outlined briefly the plant belonging to this company. He says, in effect: The Boulder, Mont., enterprise set the example for others with whom the patentee (W. L. Austin) had been negotiating, and the old La Plata lead-smelter at Leadville, Colo., was fashioned into a crude, temporary experimental plant for the Bi-Metallic Company, and the feasibility of the process demonstrated by a trial run. Subsequently, the plant was considerably improved, and, being supplied with very favorable ores, continued to run without interruption from August, 1892, to June, 1893. In September, 1803, smelting was resumed in a completely remodeled establishment, some $200,000 having been expended upon the new work. Thus, aside from the Montana experiments, which, under the direction of W. L. Austin, began as early as 1885 at Toston, and continued with indifferent success for six or seven years, the Bi-Metallic plant at Leadville may be said to have

Jan 1, 1911

By Thomas Downing

WHEN examining a coal property it is customary for the engineer to take channel samples at several coal faces. In doing so the extraneous matter, or partings, which can be removed by hand, or mechanically, with the facilities at hand, or proposed, is rejected. Where there is doubt concerning a stratum it is usually rejected from the main sample but part is taken for separate analysis. The samples are forwarded to a chemist for proximate analyses and determination of British thermal units, and, sometimes, ash fusion. Consideration is given all available commercial analyses but frequently the owner presents only the favorable ones. From the results thus obtained a general evaluation is made, monies are loaned or expended, markets are determined, and realization is estimated. In many instances, such grades are not substantiated and it is time we looked deeper for a basis which will prove more practical. Institute committees are working hard on analytic and use classifications and much valuable information has already been assembled and distributed. However, no single grade can be applied to any particular bed or region. Much study has been given the Pittsburgh No. 8 seam, yet that bed is subject to material differences in a single section; i. e., some strata of a face may differ from others in structure and analysis, particularly in sulfur content. From some localities it yields a good carbonization fuel, while in others it is chemically unfit for such use. Traveling south to the Logan, W. Va., field we find the Cedar Grove (Island Creek) seam a hard, gray splint coal. In the same field, and not far distant, the same bed changes, both structurally and chemically, and consists of excellent gas coal. In Illinois the moisture content of a bed may vary greatly in different localities. We have seen mines in which part of the coal is excellent for special purpose use but is spoiled by the product from another part of the same mine.

Jan 1, 1931

By James Munroe

APPALLING as has been the loss of life in the last 51 months, there is one slight compensation : no longer will there be in the world a cripple, in the old meaning of the term. Men handicapped by wounds or disease, there will be, unfortunately, and in numbers beyond what the world has known since the wars of Napoleon; but neither they nor the industries from which they were called off to war will be "crippled" in the sense in which both would have been had mankind not learned the lesson of conservation and come to understand that the most important field for such conservation is not in the forests and' the mines but among men and women. From the beginning of the Great War, France, Great Britain, Belgium, and most of the other Allies have studied the problem of restoring the soldiers and sailors injured through war to physical and economic efficiency; and from their experiences, especially from that of Canada, the United States has learned much. Consequently, our task of preparing for the return of our disabled men has been easier and, in some ways, more comprehensive than theirs. Complex as are the details of the machinery which the United States has set in motion to take care of the men injured by wounds or disease, the plan itself is simple. Taught by European experience, the Surgeon-General of the Army and the Bureau of Medicine and Surgery of the Navy have provided, on both sides of the Atlantic, every known surgical and medical facility for restoring the injured or diseased man to a physical condition as nearly normal as possible. While in the hospital in France or England, on the transport coming to America, and in the hospital here, the disabled man is incited in every way to believe in his future efficiency, to want to be a normal worker, to desire to retake his place in that society of workers from which he went, temporarily, to do the greater work of preserving civilization. Furthermore, since purposeful occupation is now regarded as an essential form of, treatment with most men in the hospital, especially in the convalescing stage, many of these men will have been actually started on the road to earning before they are discharged from the army surgeon's care.

Jan 1, 1919

By E. K. C. Williams, Nathaniel Arbiter

INTRODUCTION The surface processes involved in preparing ores for flotation and for operations depending on their flocculation/dispersion characteristics * vary widely in agitation dependence. Most of the reagents used for these purposes are added to grinding circuits, pump sumps, launders, or directly to flotation cells with the turbulent flow conditions usually adequate both for mixing reagents and for surface reactions without special conditioners. However, some reagent systems do require specific control of agitation intensities and reaction times, the more important of these being the following: 1. Activation of ZnS with CuSO4. With the usual conditions pH about 10, with collector added with the CuSO4, Cu 2+ is almost completely precipitated as basic compounds and as collector salt. As a result the levels of reagent in solution are extremely low which probably accounts for the need for separate conditioning. The agitation intensities are at about the 0.01 HP/ton level.** 2. Flocculation with natural or synthetic polymers. In this case the agitation problem is two-fold; first, to insure adequate initial mixing of the viscous stock solution of the

Jan 1, 1980

By R. L. Wiegel

The National Science Foundation, Erie Mining Co., and University of Minnesota Mineral Resources Research Center jointly sponsored a project to demonstrate the use of a small computer in the control of cyclone overflow size on one line in the Erie Mining Co. concentrator. The Erie circuit, similar to most taconite circuits, uses magnetic separators to reject tailings following each stage of grinding, resulting in additional variations in the demands made on the grinding circuit because of weight rejection fluctuation. Mathematical models were developed for rod milling, ball milling, hydrocycloning, fine screening, and five stages of magnetic separation. These models were used in concert to simulate the operation of Erie's circuit from rod milling through finisher magnetic separation.

Jan 1, 1980

By J. J. Mike

During the past few years the combination of continuous billet casting with in-line reduction has been studied and several machines have been built with this capability included in the design parameters. (1,2,3,4,5) In-line reduction and continuous casting in combination are obvious and attractive. As pinch rolls are already in place for the continuous casting operation, it can be readily seen that a redesign of the mechanical and electrical equipment of the pinch rolls is all that is necessary to have in-line rolling. There have been numerous in-line reduction experiments conducted by simply increasing the pinch roll pressure on existing machines. (6,7,8,9) These generally failed to produce quality billets and often resulted in internal metallurgical defects (Figure 1).

Jan 1, 1972

By H. R. MacMichael

THE rate, at which zinc ore can be sintered varies widely, depending on the characteristics- of the ore. A coarse table concentrate already roasted to a very, low sulfur content may sinter at the rate of-8.6 tons per hour per 100 sq.ft., of wind-box area. At the other extreme is a finely ground flotation, concentrate, with considerable sulfur remaining in the ore as delivered to the sinter plant, for which corresponding rate may be only 3.8 tons per hour, or 44 per cent of the first rate. A usual, size-of sinter machine in zinc plants is one with wind-box 3.5 by 33 ft., making 115.5 sq. ft. of area, and using a 100-hp. fan. Such a machine with the coarse concentrate described would produce 10 tons of sinter per hour; and with the fine, flotation concentrate would produce only 4.4 tons per hour. Ore of the latter class is -sintered at the plant of the Mexican Zinc Co. (subsidiary of the American Smelting & Refining Co.) at Rosita, Mexico. ; Consequently, an unusually large sintering capacity per ton of ore to be treated is required, and provision was made for treatment of 9000 tons concentrates per month, preroasted to. 5 to 9 per. cent sulfur. For this duty three of the usual 33-ft., 100-hp. sintering machines would have been needed.. Considering the auxiliary equipment. necessary for proportioning, handling, and mixing charge, as well as means for disposition of the sinter, a three-unit plant becomes-very complicated, especially if the capacity should be doubled later. After much study it was decided to build a single sintering unit of ample capacity for the work, the plant thus being much simpler and cheaper in construction as well as in operation (Figs. 1 and 2). The sintering machine was built with a wind-box 5.25 by 60 ft. (315 sq. ft.) and provided with a 300-hp. fan.

Jan 1, 1932

By H. Reginald Hardy, Y. S. Kim

Recent studies of inelastic behavior and acoustic emission in geologic materials further validate the concept that such materials may be considered to consist of an elastic media containing an array of pores and cracks. In the present paper this concept is investigated further by experiments in which the mechanical behavior of a number of geologic materials were studied in detail at low stress levels using ultrasonic pulse methods. Experiments were carried out on cylindrical test specimens of Indiana Limestone, Tennessee Sand- stone and Barre Granite under relatively low confining pressures (0-5000 psi). Analysis of data from these experiments indicated that there existed a low-level critical stress at which there appeared to be a transition in the mechanical behavior of the material. Under triaxial stress, results indicated that the differential critical stress was relatively independent of confining pressure, i.e., the mechanism responsible for the transition in mechanical behavior was governed by a maximum shear stress criteria.

Jan 1, 1971

By W. F. Hosford

W. F. Hosford, (Massachusetts Institute of Technology) —evelopment of methods for predicting the plastic anisotropy of textured metals is an important step toward the improvement of properties by texture control. The engineering value of the present analysis is indicated by the good agreement between prediction and experimental findings. The purpose of this discussion, however, is to point out the weakness of the assumptions on which the analysis is based. The authors state that "the relative width and thickness strains are believed to depend only on the slip direction" and accordingly they disregard the orientation of the active slip plane. where E,, cW, and et are the tensile, width, and thickness strains, A,, A,, and At are the angles between the tensile axis x, the width direction w, and the thickness direction t, respectively; and G,, GW, and 4 are the angles between the slip-plane normal and x, w, and t, respectively. Therefore, the ratio of width to thickness strains resulting from slip on a single system would be These relations hold regardless of whether the slip plane is a crystallographic plane of the {110}, (1121, or (123) type or whether noncrystallographic slip occurs. If noncrystallographic slip occurs, it might be reasonable to assume that the effective slip plane is the most highly stressed plane containing the slip direction. In this case the slip direction, S.D., the slip plane normal, S.P.N., and the tensile axis, x, are coplanar (Fig. 19) and the angles are related by following expressions: where 9 is the angle between t and the projection of the slip direction in the w-t plane (igs. 1 and 2). The normal strains, Eq. [9], become

Jan 1, 1963

By A. Soundraraj, S. Singh, R. C. Deshpande

THE detonation of a high-explosive charge having a metal-lined conical cavity (shaped charge) results in a fast-moving jet and a slow-moving slug.1-4 Clark and Bruckner reported the metallographic studies of a cast-iron slug. The present note describes the metallographic studies of a copper slug and discusses the principle of flow involved. The shaped charge consisted of a 5-cm diam cylinder of cast high explosive (60-40 RDX-TNT mixture) having a 45 deg and 0.16-cm thick copper cone. The copper (99.5 pct purity) had a grain size of 0.06 to 0.08 mm diam and a hardness of 65 to 75 Hv. These were fired into a deep container of water and the slugs were recovered undamaged. The longitudinal and transverse sections of the slug were polished, etched, and examined for mi-crostructural changes. Macroexamination revealed a radial grain flow inwards towards the center and a downward component of flow towards the base of the slug. Fig. 1 shows schematically the micro-structural changes observed on the longitudinal section of the slug. The region D near the apex and also along the outer surface of the slug was characterized by the presence of heavily deformed and twinned grains. Some of the grains were having bent or crossed twins, Fig. 2. The grain size in this region was of the same order as that of the

Jan 1, 1960

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Jan 12, 1959

By H. A. Kortmann, K. Koch, B. M. Grover, O. P. Burghardt

Addition of lime, especially when treating a hematite feed, sometimes results in swelling and a severe loss in strength during reduction in the temperature range 900° to 1100°C and in grain disintegration in the temperature range 400° to 600°C in a weakly reducing atmosphere. Swelling and/or grain disintegration of pellets is often the reason for trouble in blast furnace operation, resulting in a decrease in the rate of smelting. Following a brief description of the test procedures employed (measurements of swelling, pressure-reduction-softening and grain disintegration), some results are given which were arrived at when testing pellets from industrial plants. Results of systematic tests are presented, where the effect of the quantity and quality of the gangue upon the behavior during reduction of pellets is illustrated. Varying amounts of quartz and limestone were added to a high-grade hematite ore and, then, pellets produced in a pot grate. The relationships of the behavior of the fired pellets during reduction are presented, among others, in the ternary system CaO-FeOn-SiOP. Finally, an attempt is made to explain the reasons for swelling, loss in strength, and grain disintegration.

Jan 1, 1974