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By William R. Webster

In view of the great interest now taken in the tests of castiron and details of foundry practice, with the number of investigators at work, and recent improvements in the methods of research, it would seem that the time is ripe to attempt the solution of some of the many problems with which iron founders have to contend. Recent papers and discussions on these subjects* have opened up s large field for investigation, and have emphasized the importance of many considerations generally overlooked. With the view of promoting a comprehensive and systematic discussion, I have attempted to tabulate, in conveilient form, some of the most important points for investigation, on the general plan suggested, with such good results, by our former President, H. M. Howe, for the discussion on the Physics of Steel, at the Virginia Beach meeting, last year. This table can, no doubt, be modified or enlarged to advantage, and put in shape to serve as a guide or reminder to all who are interested in this line of work. Suggested Lines for Discussion and Investigation. I.—Correspondence between chemical composition and melting point, fluidity, shrinkage, fracture, chill, micro-structure, and other physical properties. II.—Influence of: I. Cupola mixture, use of steel and other scrap, oxidized or clean material, 2. Manner of melting, flux, etc., 3. Casting temperature, A. Fracture. 4. Manner of handling melted metal and B. Micro-structure. method of casting, C. Physical properties. 5. Size and form of casting, D. Shrinkage. 6. Kind of mould, green sand (under dif- on 1 E. Chill. ferent conditions of ramming, amount F. Residual stress. of moisture, and skin-dried), dry sand, G. Condition and quan loam, and chills, tity of carbon and 7. Rate and mode of cooling castings, other elements. 8. Manner and temperature of heating for annealing, 9. Additions of nickel or aluminum,

Jan 1, 1896

By R. M. Zimmerman

INTRODUCTION Tuff is being considered as a possible geologic median for the underground storage of commercial high level radioactive wastes by the Department of Energy (DOE). DOE has the responsibility for developing or improving the technology fir safely and permanently isolating these wastes. DOE programs must satisfy requirements established by the Nuclear Regulatory Commission (NRC) for the licensing and regulating of these storage facilities (NRC 1981). Pertinent draft NRC requirements are: 1) releases of radioactivity to the environment must be within prescribed limits and 2) emplaced canisters containing wastes must be retrievable up to 50 years following emplacement. High level radioactive wastes produce heat in storage and it is essential that the thermal/mechanical/hydrological response of the host rock will not significantly degrade either the structural performance o£ the repository or the ability of the natural or engineered barriers to retard radionuclide migration. The Nevada Nuclear Waste Storage Investigations (NNWSI) was established by DOE to evaluate the suitability of disposing of high level nuclear wastes on or near the Nevada Test Site (NTS) (NNWSI 1980). NNWSI has focused exploration and site evaluation on the tuffs of Yucca Mountain. Field testing is essential to support site characterization and repository design efforts. Preliminary studies have been conducted indicating that tuffs in G-tunnel on the NIS contain welded and nonwelded tuffs that have similar properties to those in Yucca Mountain. Thus, field testing can be accelerated. This paper discusses the issues supporting the planned field experiments in G-tunnel. Issues not related to rock mechanics are not included.

Jan 1, 1982

By O. B. Hopkins

Essentially all production for Peru came from the three established fields in coastal northwestern Peru (Fig. 1). These fields are known as La Brea-Parinas, Lobitos, and Zorritos, in order of importance. Together they produced 13,496,880 bbl., as compared with 15,838,605 bbl. in 1938. Zorritos Field.—Of the total production shown on Table 1, the Zorritos field was responsible for a relatively negligible amount estimated at 40,000 bbl. This small field, which is over 50 years old, was purchased by the Peruvian Government in the spring of 1939 from the Piaggio interests. The Government operated this field along with its near-by National Reserve areas, largely under supervision of Department of Mines officials, and the total production rate for both old and newa-areas was estimated to have increased by Oct. 1 to 166 bbl. per day. as compared with the 1938 average of 110 bbl. per day. Construction is said to have begun on a refinery that is to have a capacity of 1000 bbl. per day and is to include a gasoline-extraction plant, and on a pipe line to bring fresh water 20 miles from the Tumbes River. Lobitos Fields.—The Lobitos fields, some 70 miles south of Zorritos, produced approximately 2,650,000 bbl., or almost the same amount a* in 1938. La Brea-Parinas.—The International's La Brea-Parinas property, immediately south of the Lobitos property, produced 10,806,880 bbl., or 80 per cent of Peru's production. During the year 73 wells were drilled on the Estate, mostly in the semiproved area: 44 by rotary, 13 by cable and 16 by star rigs, as compared with 34 by rotary, 11 by cable and 20 by star in 1938. The most important of the several semiexploratory wells sunk was No. 3075, which late in December was brought in at a depth of 4500 ft. with an initial production of 1500 bbl. per day, based on

Jan 1, 1940

By S. P. Burke

THE presence of gas in coal mines necessitates the use of costly ventila-tion arrangements and the use of expensive mining methods. On the other hand, the gas itself in many instances is of considerable intrinsic value, and its separate recovery might conceivably be a profitable under-taking. This paper is concerned with a study of the movement of gas in coal strata with the object of determining the laws governing gas move-ment and thus making at least a preliminary step toward the solution of the more practical problem of its control or recovery. Naturally, so important a subject has received much attention from scientists and engineers. In most cases, however, the studies have been concerned with the origin1?, the amount2, the composition3 and the method of retention4 of the gas in coal; or, from the more practical side, have been concerned with the phenomena and conditions associated with outbursts5 or explosions and their control. Numerous studies also have been made of the permeability of coal to gas6, of gas pressures measured in coal seams, etc. The authors are unaware, however, of any attempt to present a consistent or complete picture of the laws governing the movement of gas through the coal.

Jan 1, 1935

By P. de Vitry, Willis P. Mould

The wire saw is a tool not less than 60 years old, probably nearer 100 years old. It was developed in Europe and is reputed to have originated in Belgium. Frombold is said to be the original patentee. Wire sawing equipment, as indicated in Fig. I, is very simple. It consists of a three-strand wire cable, usually pis or 1/4 in. in diameter, or a single flat ribbon of medium hard, tough, alloy steel twisted into a helix of those diameters, made to form an endless belt of any length up to several thousand feet. The wire is guided into the cut by sheaves mounted in slides on steel columns situated close to either end of the cut. The feed motion usually is controlled either by gravity or by hand-operated feed screws. The steel columns or "standards" range from 15 to 30 ft. in length. At the top is a swiveled arm supporting a sheave similar to the traveling sheave below. Immediately under the swivel-mounted sheave is a guy plate or collar with shackles attaching four chain or wire-rope guys with suitable tightening devices, or with two guys and two jack legs for supporting the standard vertically or at any desired anale. The usual drive is by a 10-hp. motor through a gear reducer, on which are Insti- two grooved sheaves, One of which is keyed and the other free running On the shaft. Tension is provided by a car running on a track in line with the driving sheave

Jan 1, 1948

By Harry K. Ihrig

Jan 1, 1947

By Bunting S. Crocker

In the summer of 1961, the Anaconda Research staff and Kilborn Engineering Ltd. began a study to investigate the possibilities of using some form of autogenous grinding in the new concentrator which Anaconda was planning to erect at Butte, adjacent to their Berkeley pit. The following criteria applied to the project: 1) The Butte mill was to be able to handle 36,000 to 42,000 tpd of copper ore, taken from the Berkeley pit and adjacent underground mines. 2) The plant was to be built in six units. 3) It would be started up two units at a time. 4) Equipment from the Anaconda mill was available for use in the new location. 5) Tonnage would be maintained at Butte and Anaconda, with equipment being moved down as required. 6) The ore from the Berkeley pit was known to vary widely from place to place in the pit and to be generally soft and friable.

Jan 5, 1964

By Jacques Friedel

Jan 1, 1964

By P. St. J. Perrott

AN explosive of balanced composition might be expected, on first consideration, to develop maximum propulsive strength.1 This hypoth¬esis is based on the assumption that an excess of oxygen would act simply as an inert material with a consequent lowering of flame temperature, also that a deficiency of oxygen would tend toward incomplete reaction of the combustible materials, thereby preventing development of the full strength of the explosion. Actually, however, it can be shown both theoretically and experimentally that an explosive having a certain oxygen deficiency will develop the greatest propulsive strength. This fact has been known to the technical staffs of explosives manufacturers for many years, but it has not always been recognized by explosives engineers in the field. For example: There is a fairly widespread opinion that the wrapper of a stick of dynamite is merely a container for the explosive and that it plays little if any part in the development of propulsive strength. Actually, it can be shown that the wrapper enters fairly completely into the explosive reaction. In the case of most gelatin dynamites, a given weight of explosive from which the wrappers have been removed will develop considerably less strength than the same weight of explosive plus wrapper, in spite of the fact that the latter combination contains less weight of the actual explosive ingredient. It can also be shown that a cartridge 7/8 in. in diameter may be stronger, weight for

Jan 1, 1928

THE award from the fund established by Mrs. John-son, in memory of her husband, J. E. Johnson, Jr., to be given to some promising engineer, not over 40 years of age, because of meritorious research, inven-tion or contribution to the professional literature of iron and steel along the lines of blast-furnace process, has been given, for, 1928, to P. H: Royster. Mr. Royster was born at Raleigh, N. C., in 1888. and graduated from the University of North Carolina, in 1907, taking his A.M. degree at, the same school in 1908. He then went to Harvard where he continued research work in physics. After engaging for a while in commercial research in the turbine department of the General Elec-tric Co. and with Cutting and Washington he joined the staff of the Bureau of. Mines in 1916 and was assigned to work on the physical chemistry of the blast-furnace process. He worked with A. L. Feild on slag viscosity and they jointly presented-to the Institute the. papers on "Temperature and Viscosity Relations in the Ter-nary System CaO-A12O3-SiO2" (TRANS. LVIII, 658) and "Slag Viscosity Tables for Blast-furnace Work" (TRANS. LVIII, 650). He also presented a paper on "Production of Ferromanganese in the Blast 'Furnace" .(TRANS. LXII, 18), and jointly with T. L. Joseph contributed a paper on "Effect of Coke Combustibility on Stock Descent in Blast Furnaces" (TRANS. LXX, 236), and another on "Pyrometry in Blast-furnace Work" which was included in the special pyrometry volume published in 1920. The titles of these works perhaps sufficiently indicate the part Mr. Royster has played in the notable research work on the blast-furnace process carried on by the Bureau of Mines, and for which the committee recommended him to the Board of Directors to receive the Johnson award.

Jan 2, 1928

By Peter M. Anderson

IN recent years many prophets have arisen who hold that gold has outlived its days and that its monetary use is now an anachronism. These prophets include well-known politicians, economists and businessmen. Some of them have called it a joke that metal should be dug up at heavy cost in Africa and elsewhere and shipped to the United States of America only to go underground again at Fort Knox. Others have claimed that all the gold in the world could be sunk in the ocean without anyone being the poorer. The fact that you have invited me to address you on the future of gold may perhaps reflect the fears caused by these various predictions. At present the prophets' taunts show no sign of coming true. The demand for gold is greater than ever before, although stocks held are the largest in history. Nearly all governments have gone to great lengths to suppress any demand that might be made by the public; they have reserved to themselves the right to hold gold and have lost no opportunity of satisfying their own demands. Where the public has been allowed to buy gold, the demand has proved impressively strong. In India the price of gold equals about $82 per fine ounce, having been $90 earlier in the year; in Egypt $65 to $70, after having been $87, and elsewhere it is even higher. In Palestine, for instance, the golden sovereign is traded at about £5, equivalent to $86 per fine ounce, having been nearly £6, equivalent to some $100 per fine ounce, earlier in

Jan 1, 1947

By W. F. Durfee

The apparatus described in this paper was designed by the writer, in the year 1869, for use in the laboratory of the " American Silver Steel Works," at Bridgeport, Conn., where only the vacuum-pump was erected ; but on two subsequent occasions I have had the combined vacuum-pump and table-blowpipe constructed as represented in the drawings, in which Fig. 1 is a general elevation of the apparatus, the air-chamber being sectioned vertically; Fig. 2, a plan of the air-chamber; Fig. 3, a vertical sectiotnal elevation of the vacuum-pump, the section being on line C L), of Fig. 4, which is a horizontal section on line A B, of Fig. 3. The vacuum-pump is constructed of copper, and consists of a vacuum-chamber, E, supported upon the upper expanded end of a vertical pipe, Q. The vacuum-chamber is provided with four nozzles, C, F, I, D (Fig. 4), two of which are shown in section at A, B (Fig. 3). Passing vertically through the centre of the vacuum-chamber E, is seen the water-supply pipe P, whose lower extremity incloses an internal pipe p, which is supported, and placed in communication with the vacuum-chamber E, by means of the two elliptical nozzles n, n. The upper part of the pipe p is closed by a conical cap, and its lower end is in the same plane with the extremity of the watersupply pipe P, within which it is placed. The relative sizes of the pipes P and p are such that an annular adjutage, one-sixteenth of an inch in thickness, is formed between their lower extremities, through which the water from the supplypipe P passes into the pipe &, drawing any air that may be in the

Jan 1, 1885

By E. E. Malouf

For centuries small amounts of copper have been recovered from acid mine-drainage waters. In recent years, the expansion of copper-bearing waste dump leaching for copper recovery has established a technological basis that is rapidly converting the art of copper leaching into a science. Copper leaching and recovery from solution has become an important adjunct of nearly all copper mining operations. Leaching of copper, whether from copper- bearing ore or waste, follows well established chemical reactions commonly in an acid circuit, but where leaching of copper is to be made in rock that is a high acid consumer, ammonia and ammonia carbonate, as well as cyanide leach solutions, can be used effectively. Current hydrometallurgical processes are being applied at an ever increasing rate to recover the trace amounts of copper in copper mine waste by in-place leaching. Currently approximately 300,000 tons of copper are produced annually in this manner while as recently as ten years ago, only one-eighth of this amount of precipitate copper was produced. Where copper occurs as an oxide in higher concentrations as to be classified as an ore rather than waste, then the hydrometallurgical processes are applied as percolation or agitation leaching in vats, pachuca tanks or prepared heaps. This approach gives better control over the recovery of the leach solutions, particularly in the processes where ammonia or cyanide leaching agents are to be used.

Jan 8, 1972

By A. Brown

RAPIDLY rising world demand for mineral pro- ducts has accelerated depletion of the more readily accessible ores, particularly those of premium grade. Operations must proceed at a faster rate to deeper horizons, where there are problems of ground control that restrict economic recovery of the mineral and introduce new hazards to mine personnel. For some of the new Canadian mining fields severe problems of ground stress are still in the future, but much of Canada's mineral output comes from well established mines that have reached considerable depths. It must also be anticipated that the depletion of premium grade ores will eventually necessitate mining low grade material at competitive cost, and unsolved problems of ground control can materially increase costs. Studies of ground stress phenomena in underground workings are therefore considered a present-day necessity, especially since these investigations must be a long-term effort owing to the highly complex nature of the problem and the difficulty of making full-scale observations.

Jan 8, 1958

By David Mitchell

THE production of fluorspar is one of the smaller nonmetallic indus-tries in the United, States with a capital investment-about $10,000,000. Shipments from United States mines1 in 1936 totaled 176,231 short tons valued at $3,111,268, an average price of $17.65 per ton. The United States produces about 40 per cent of the world's fluorspar, of which about 90 per cent comes from the Illinois and Kentucky deposits along the Ohio River.2 Further detailed information on the fluorspar industry in the United States is given by Hatmaker and Davis.28 Fluorspar is marketed according to the following relative quantities and specifications: Consump- Specifications, Per Cent Use Form tion in 1936, Per Cent CaF2 SiO2 Fe2O3 Metallurgical Gravel 79 +85 -5 or lump Ceramic.. Ground 10 +95 -3 -0.1 Acid Ground 11 +98 -1 The concentration of the coarser sizes presents relatively little diffi-culty, good recoveries being obtained with jigs and tables. However, sizes smaller than about 10 mesh cannot be successfully treated by ordinary gravity separation methods and so have been accumulating as

Jan 1, 1938

By Harry K. Ihrig

Jan 1, 1947

RUfUs J. Foster, Scranton, Pa. (communication to the Secretary*) :—In answer to one of the inquiries made of Mr. Conner, and as a matter of historical record, I beg to say that the idea of supporting the strata over worked-out areas in coalmines by flushing the openings full of culm originated and was put into actual practice by the late R. C. Luther, a former member of the Institute, at that time Chief Mining Engineer, and later General Manager, of the Philadelphia & Reading Coal & Iron Co. In the early 80's the Philadelphia & Reading Coal & Iron Co. purchased from Messrs. Hecksher & Co. the Eohinoor colliery, situated in the western part of the borough of Shenan-doah, Pa. On taking possession of the colliery the Philadelphia & Reading Coal & Iron Co. made a conlplete resurvey of the mine-workings, giving an absolutely correct map which showed not only the plan of the mine-workings, but also every improvement on the surface over the workings, and the marked features of the surface of the ground. Tidal elevations were shown at every eurvey-station in the mine and on the surface, so that, as is the case with all the maps of the company, contour-maps of either the surface or the bottom of any coal-seam, or geological cross-sections, could be constructed directly from the information on the mine-maps. In a cornparatively short time after the company took possession of the colliery, the workings which extended under the western portion of the borough of Shenandoah began to cause trouble and damage dwellings and other buildings in that section of the town. The lots in this section had been sold, in many cases, to individuals by the Gilbert & Shaefer Estate, owners of the coal-lands on which the colliery was located. In

Jan 1, 1912

Faulty rock dusting of the New Orient Mine at West Frankfort, Ill. was declared to have been the primary cause of the extent of the blast that killed 119 men on December 21. Walter Eadie, state director of mines and minerals, ascribed the explosion to the ignition of methane in a working place about a mile northwest of the shaft of the mine. The initiation of the combustion was either by a spark from electrical machinery or from men smoking in the mine. It was surmised that a train of empty cars stalled in a ventilation door, had caused sufficient disturbance in the ventilation system to permit accumulation of gases. The Federal Bureau of Mines said that the Illinois explosion was caused by an electrical spark that touched off the clouds of gas present because of the faulty ventilation equipment. The bureau report listed three conditions as primarily responsible: An inadequate ventilating system, operation of faulty electrical equipment and the presence of large accumulations of fine coal dust capable of exploding. "This coal dust, principally along roadways, was not removed from the mine or rendered inert by the application of sufficient rock dust," the report stated. Investigations showed that an even more disastrous blast was averted because the explosion eventually reached areas where it could expand into open workings and where enough rock dust had been applied to retard it.

Jan 1, 1952

By Harry A. Roe

THE power drag scrapers and the slackline cableway excavator have been called "long-range excavators." Broadly, their field of usefulness is restricted to work in which their long range of action permits them to operate economically, and which other, possibly more conventional, excavating units cannot do. Both of these machines dig or lift material and transport it to a remote dumping point. They combine these two functions in a single machine, nearly always in a single straight-line motion. [ ] The purpose of this paper is to examine the important features that distinguish the machines in this group from each other, as well as from other groups. The Machines The "power drag scraper" is a long-range excavating machine that employs a bottomless drag scraper operated back and forth between digging and dumping points by two haulage cables. The typical arrangement is that of Fig. 1. This is the "slusher" of the underground mine, as well as the "dragline scraper" of the sand and gravel industry, and other open-pit mining operations.

Jan 1, 1937

By Herbert Dumont

Since 1947 Preussag AG Metal1 has used a process for fuming zinc- and lead-containing dump slags and residues from vertical retorts in a half-shaft furnace at their Hüttenwerk Harz at Oker. Contrary to the classic shaft furnace, only one side of the half-shaft furnace is fitted with tuyeres. The opposite side is a bricked slope. The upper shaft section is piped. There zinc vapor and combustion gases are burned by sucked-in air. Gases and fume enter a boiler located on the rear length of the furnace via a piped fire bridge. The gases are then cooled in an air preheater prior to dedusting in a bag filter. The furnace is charged with briquettes of metal-bearing materials, coal and pitch. The leaded zinc oxide fume is comparatively rich in both lead and zinc. The copper in the feed is recovered in low-copper matte. The slag can be discarded. The Oker plant comprises 13 furnaces of 2.9 to 4.9 m length in the tuyere area. Two other plants in Italy and Spain are processing zinc leach residues by this technique. Fuming of zinc-lead-oxide ores as well as partially roasted sulfide- zinc-lead-copper bulk concentrates will be possible.

Jan 1, 1970