Search Documents

By W. H. Fulweiler

The writer would define the term "Use Classification" as a discussion of the qualities that coal should possess to fulfill the requirements of the industry or process in which it is to be used. The general problem of the gas industry is to transform the maximum amount of the thermal energy in coal into a gas of specified quality. The qualifications that a coal should possess to be useful in the gas industry are complicated by probably a greater number of factors than in most industries. The most important of these is the delivered price of the coal. While the- general problem of the industry is as given above, yet the actual problem is the production of gas of a specified quality at the minimum cost. The relative cost of coal and the selling prices for the residuals which are influenced to a large extent by geographical locations are of determining importance as effecting the cost of the gas. It is unfortunate that we cannot disassociate cost figures from a discussion of the desirable characteristics and this results frequently in the use of coal in one location that will be looked upon as quite impossible in another location more favorably situated. Without going into any discussion of the freight rate problem we might merely point out that in general the freight on the coal is equal to or greater than the mine price. It must be evident, therefore, that price must always be considered in any discussion of the effect of the characteristics of a given coal. Two Classes of PRocesses In discussing the characteristics of coals for use in the industry, we must divide the processes in use into two classes: (1) where the coal is destructively distilled at high temperatures resulting in the formation of coke in the liberation of gas and by-products, and (2) where the coal is consumed by combustion in air or steam with a production of gas and by-products leaving only clinker as a residue. The Germans differentiate these two types of processes in their words"' entgasung'" and'" vergasung."' In the distillation processes, we have the effect of the coal on the yield of gas and its quality; the quantity and quality of coke; and the

Jan 1, 1930

SINCE the adoption by the U. S. Bureau of Standards several years ago of specifications for standard 100- and 200-mesh sieves, frequent requests have been received that this Bureau test and certify sieves of other sizes than these. With a view to the adoption of a series of standard testing sieves which might be of use to all industries making fineness tests, this Bureau for .two years has been studying the question of such a standard screen scale. Various scales that have been proposed were considered, and information was sought of representative firms in the various industries interested as to their requirements. Manufacturers of sieves have also been consulted as to the desirability of different screen scales and the practicability of their manufacture. As a result of this study of the question, a conference was called at the Bureau of Standards, Apr. 20, 1916, of representatives of various committees of the American Society for Testing Materials, American Society of Civil Engineers, American Institute of Mining Engineers, American Foundrymen's Association,. [Mining and Metallurgical Society of America, American Water Works Association, American Institute of Metals and the American Spice Trade Association; also representatives of the Committee of Revision of the U. S. Pharmacopoeia, the U. S. Geological Survey, the U. S. Bureau of Mines, the U. S. Office of Public Roads and Rural Engineering, the U. S. Office of Grain Standardization and the U. S. Bureau of Standards; also representatives of a number of private firms engaged in industries in which sieves are used, such as the glass, the drug milling, the abrasive, the asphalt, the mining, the spice, the chemical, and the graphite industries; also representatives of the firms in this country manufacturing wire cloth and sieves. This Conference, after considering the various screen scales either proposed or now in use, adopted as a Standard Screen Scale that given in Table 1, and recommends that it be adopted generally by scientific,

Jan 6, 1917

By T. Olrog

Dissemination of technical data on developments in rock-blasting techniques in Sweden initially takes place as personal contacts and contacts between companies. In addition to these informal contacts, contacts occur in Sweden in a somewhat more organized form. There exists an informal working group--the Rock Blasting Committee--which consists of a number of personal representatives from various companies that perform rock blasting on a large scale and from firms manufacturing the equipment that is used. This means that people from both mining and construction companies get together, plus the manufacturers of explosives, drill steel, drilling machines, and loading equipment. This working group has, so far, succeeded very well in ignoring the purely commercial interests of the companies concerned. Cooperation in this form was started in the 1940's when the tungsten-carbide drill steel was invented-the group originally concentrated entirely on the development of that product. Their activities have been broadened since that time and now a meeting is held every year, at which practical experiences are reported. Only in the past five years have subjects relating to blasting procedures to avoid rock damage been treated at such meetings. This, of course, does not mean that such techniques had been neglected previously. It does, however, reflect the fact that practice in this field is still under development. Why do we try to be careful about the rock surfaces? Obviously, it is a question of economic evaluation. An even rock surface provides, in certain cases, the conditions for more favorable maintainance costs later on, greater strength, and a diminished risk of slides. The economic connections in this field, however, are neither simple or clear. A well-controlled blasted rock surface limits the need for concrete when you later build the concrete constructions. In this respect, the connections are all the more clear. In certain situations, such as tunnels for hydroeletric power plants, a good rock surface that is not lined is hydraulically more favorable than a more coarsely blasted surface. This permits a gain in the height of fall, but the

Jan 1, 1970

By R. S. Shoemaker, F. W. McQuiston

REFINERY SECURITY "Highgrading, " a polite word for stealing gold and silver, has been a way of life since the metals in native form have been mined or produced. Unfortunately, in the past, highgraders were not always severely prosecuted or even looked upon unfavorably in their communities. Recent high metal prices with attendent world wide publicity, however, has made highgrading or thievery again a serious problem in mines and plants. When a small button of gold the size of the end of ones little finger has a value equal to about one week's wages, the safe-guarding of gold production by enforcing tight security measures becomes a prime responsibility of management. The higher the gold price, coupled with unrestricted owner- ship, the greater the temptation to “get-your-cut”, and diligence by management must become an integral part of plant security. Primary security begins by knowing the expected gold production and the sampling of a gold ore mill feed for this determination has proved not reliable. However, solution flows can be accurately sampled and measured thereby closely predicting the gold recovered each day as precipitate. The progressive record of total ounces of gold contained in the precipitation press, referred to in cyanidation plants as I1solution calll1 predicts the accumulated production. The "callH is an important adjunct to security and extreme caution must be used so that the pregnant solution meter and sample are confined in a security area. It should be recognized that this key sample may be the target for Ifdoctoring" by trusted insiders (assay office employees) as a preliminary step for stealing precipitates and/or metal. Security measures similar to the following were adopted after one operation experienced a sizeable theft of gold precipitate and metal by trusted employees. The refinery area where precipitates are handled and melted to bullion and all other gold products are kept should be completely enclosed with a tight security fence preferably of solid construction. Access to this enclosure should be through one of two electrically controlled gates, one for personnel and another for occasional truck entrance. Admittance should be restricted to essential personnel who are required to sign a register in and out with the date and time. I£ there is a "back gate" to the restricted fenced area, it should remain locked except in an emergency and then opened only by a supervisor. Television monitoring cameras viewing the gate entrance and other sensitive areas connected to a viewing screen located in the general office afford visual observation at all times.

Jan 1, 1975

By Chase Palmer, Edson S. Bastin

While the reducing action of organic matter, of ferrous sulphate, and of hydrogen sulphide has frequently been invoked to account for the deposition of native gold and silver from ore-forming solutions, the high efficiency in this respect of certain of the metallic minerals which form the ore itself has not been suffciently recognized. If a little finely powdered chalcocite is placed in a test-tube arid 2 or 3 cc. of a dilute solution of gold chloride are poured over it, two or three shakes of the tube suffice to remove all the gold from the solution. The color of the solution changes from yellow to pale green, showing that copper is dissolved simultaneously with the precipitation of metallic gold. If a piece of chalcocite is hung in a dilute aqueous solution of silver sulphate (1/40 normal), a coating of silver begins immediately to form on the mineral, and within a few moments a beautiful silver tree has developed, similar to that formed when metallic zinc is immersed in a similar solution. When similar experiments are conducted with other sulphides and with certain arsenides and sulph-arsenides, especially those known to be commonly associated with native silver in ore deposits, it is found that these minerals differ greatly in their efficiency as precipitants, especially in their effect on silver solutions. The tests made with most of the minerals were qualitatipe only, but the reactions of a silver sulphate solution on chalcocite and niccolite were submitted to quantitative study to determine the nature of the reactions involved. Quantitative studies of the reactions with other minerals are now in progress

Jan 1, 1914

By Olav Dalen

A HUNDRED years have passed since Wöhler made the first few particles of aluminum by decompos-ing aluminum chloride with potassium. In 1854 Deville used sodium to decompose the double chloride of aluminum and sodium, but even various subsequent improvements of the process, especially by Castner, did not sufficiently decrease the cost of the metal to bring it into general use. In 1862 Monckton proposed to reduce Al O? with carbon by the aid of the electric current, but the efforts of the Cowles brothers to do so were not successful and in 1884 they turned to making aluminum alloys by electrolysis. At about the same time Hall in America and Heroult in France success-fully worked out the technology of dissolving A12O3 in fused cryolite and electrolyzing the bath. It is hard to realize that forty years ago the annual production of aluminum was only 30 to 40 tons per year and the price of the metal thirty times what it is today. Great strides in decreasing the cost of production, improving the quality of the metal, and increasing the output have been made in the lifetime of middle-aged men. The large consumption of electrical energy in the form of direct current makes it necessary to locate aluminum-producing plants near waterfalls, to avoid transmission losses. Norway with its abundant water-falls is therefore a logical place for the development of aluminum production, even though it is necessary to import the bauxite, which is the raw material of the process. It was foreigners who first started the aluminum in-dustry of Norway and the first two plants were built by the British Aluminium Co. in 1906 to 1908; one at Vigeland near Kristiansand, and the other at Stavan-gerfjord in Nordfjord. These two plants are still oper-ating and producing over 3000 tons a year. When the plant at Vigeland is enlarged the production of the company will be more than 4000 tons a year.

Jan 11, 1927

By Samuel L. Hoyt

This paper gives a brief description of an investigation made several years ago on the diffusion of zinc into copper. The material for that study was furnished in the form of thin copper strips coated with zinc. The result was required rather quickly and at not too great an expense, and especially information was desired as to the rate at which zinc would diffuse from the zinc coating into the copper and the temperature at which the operation should be carried out. A study of the requirements of this problem indicated that the solution might be secured by means of six determinations. This is the smallest number that will give the information desired and, at the same time, furnish checks on the accuracy of the determinations which justify an abbreviated experimental program. This does not count a preliminary test which was designed to give some idea of the correct temperature to use. The minimum number of temperatures that can be used is two. Knowing the rates of diffusion of zinc into copper at two properly chosen temperatures, it is possible to calculate the rate for any other temperature, and also to check the accuracy of the determination by means of the heat of diffusion, which is calculated from the effect of temperature on the rate of diffusion. The minimum number of determinations at any one temperature is three. The amount of diffusion which occurs at a fixed temperature is definitely related to the time of diffusion, so that by determining the amount of diffusion for three different time intervals, this relationship may be established and possibly a check on the accuracy may be secured. This accounts for the six determinations or experiments, and suggests the logical plan of the work. The check used here is not generally applicable to diffusion phenomena, but it seems to hold closely enough for the limited amount of diffusion in this investigation to justify its use. The samples used were 5 to 6 mils thick and about 1 in. square. They were placed between iron blocks and set in the hot zone of a nichrome furnace which had been brought to the desired temperature Time was taken from the moment the samples reached the furnace

Jan 1, 1929

By Joseph Pogue

OVER a period of years the writer has presented a number of studies1 on various aspects of proration, in a progressive attempt to analyze critically and constructively the economic complexities of this interesting institu-tion, which in a decade has revolutionized the economics of oil production in the United States. In the course of the investigations leading to these papers, the changing nature of proration and the principles under-lying its evolution have gradually become clear, so that it is now possible to depart from the analytical method and to construct a synthesis of the steps that, if furthered by the industry, should carry proration past the economic hazards that still surround it to the goal of maximizing the value of the petroleum resource to the industry and the public alike. NATURE OF PRORATION Proration literally means the allocation of demand among competing producers on a pro rata basis, but the term now carries a much broader significance for it is employed to describe the entire process by which the production of crude oil in the United States is regulated. There is naturally much confusion of thought on the subject, for proration is an evolving system of control based upon principles of conservation and equity and embracing a body of practices that are tending to adjust themselves to the needs of the situation but are subjected to varying and divergent influences in the process. As it is now constituted, proration is a planned production measure designed to prevent waste, insure ratable takings, and balance supply and demand. The procedure is administered by State regulatory bodies through use of the police power of the States under authority of State conservation laws; the practice is supported by a considerable degree of voluntary conformance on the part of operators; and the Federal Government has accorded its cooperation by providing advisory quotas, circumscribing imports, checking movements of hot

Jan 1, 1939

By W. J. Sharwood

The assay or estimation of the total gold content of an ore presents little difficulty, when circumstances permit of securing a thoroughly representative sample. The general practice has been fairly standardized, and such errors as occur in the results obtained are for the most part attributable to the methods of sampling rather than to those of assaying, while duplicate assays made by skilled workers usually agree closely. When it is a question of estimating the "free" or amalgamable gold of an ore, as opposed to the total gold, there is but little uniformity in the methods employed by different workers, and often equally little in the results obtained when duplicate determinations are attempted, no satisfactory standard method having been generally adopted. The methods in use are of two general types—"panning" and "amalgamation." Panning For the estimation of the value of the visible gold by panning or washing, a weighed sample may be taken, ranging from an ounce to several pounds; a kilogram or 2 lb. is a favorite quantity for laboratory tests, while a prospector often uses a full miners' pan, say nearly 20 lb. or 10 kg. In the case of rich quartz, ground to about 30 or 40 mesh, a Mexican horn is convenient, using 1 to 8 02;. of material, and a 6-in. frying pan is favored by many prospectors in dry districts. Bateas, plaques, and dishes of various patterns are used for the same purpose. With these, fairly close results may be obtained by using for ocular comparison standards consisting of weighed amounts of gold of similar character as regards purity, fineness of division, and the general shape of the particles, which standards are preferably obtained from gold of the same locality, or the same deposit, as the ore or gravel being tested. Men working in one particular district sometimes become surprisingly expert in thus judging the value of an ore by the eye, the weights of both ore and gold being guessed. On the other hand, many have been led to overestimate the value of ore and gravel from unfamiliar localities, where the gold has been very finely divided or of unusually high silver content, and a novice may

Jan 1, 1916

By T. S. Jr. Sligh

OF all the qualities that are essential in a good cigar tobacco none is quite so important as the burn. This term is general and includes many points, the most important of which are evenness of burn, color of ash, firmness and coherence of ash, and fire-holding capacity. The fire-holding capacity refers to the length of time the leaf or cigar will continue to, glow after ignition. Chlorides tend to prevent complete combustion and products are formed thereby that are injurious to the flavor and aroma. On the other hand, the carbonates of the alkalies, particularly of potassium, aid the combustion and increase the fire-holding capacity. Barth1 thought that the harmful effect of the chlorides was due to their fusing and coating the tobacco, thereby preventing complete combustion. Schlosing,2 Nessler,3 and Garner,4 suggested widely different theories to account for the favorable action of potassium salts. In order to study carefully the action of the various salts upon the course of combustion of the cigar a knowledge of the temperature of the burning cigar is necessary. Lehmann5 who seems to be the only investigator who has made any attempt to determine the temperature of a burning cigar gives 480° C. as the maximum temperature which he recorded. It is evident, however, that his measurements were in error, probably on account of the method and apparatus used, since the lowest visible red corresponds to a temperature of about 575° C.

Jan 9, 1919

By Richard Moldenke

So FAR as the quality of the product is concerned, the history of the production of pig iron for foundry purposes is one of constant retrogression. The steps in this deterioration began with cold-blast charcoal pig iron, then anthracite iron, coke iron; then gradually warm to hot-blast coke iron, with the charcoal furnaces also heating their blast to get greater tonnages, and finally the present day hot-blast coke irons with scrap additions to the ordinary burden that, according to one European report, have gone as high as 135 per cent. Parallel with this quality retrogression is the enormous increase in furnace tonnages from about 15 tons daily to over 1000 tons per day in exceptional instances of modern practice. The key to this situation is economic pressure. The effect is a growing differentiation between furnace production for gray iron and malleable foundries and for the production of commercial steel. As the foundry is often compelled to draw upon the pig irons made for steel purposes, for economic reasons, whereas the steel industry does not draw upon foundry pig irons proper, the situation is resolving itself into one of grave consequence for the life of the gray-iron castings industry, and hence the intensive present-day feeling in foundry circles for rigid specifications to govern the quality of pig irons sold for foundry use. In the discussion of a paper on the use of scrap in the blast furnace held recently in the Institute, a very pertinent remark was made by one of the participating furnacemen, who confessed that "the things found wrong by the foundryman with his iron were beyond his depth." It may be added that those things are also beyond the depth of most foundrymen who, however, know from their results that they are getting poorer castings today with many pig irons than they did with those same brands in former years. Under the former fracture buying, the foundryman at least could select the strongest metal, as judged by the sledge, from various brands of similar fracture and pig section, and his results proved the soundness of his conclusions. With the advent of iron analysis, and in spite of the growing uniformity of the metal through greater tonnage

Jan 2, 1927

ON FEBRUARY 4, 1952, the Phelps Dodge Corporation signed Contract GS-00P(D)-12068 with the United States Government. This interesting document dealt with the "Bisbee East" project as part of the Government's program to increase the supply of needed copper by encouraging private enterprise to expand production. The ore deposit involved was a relatively small body of low-grade ore lying east of the remnants of the old Sacramento Hill deposit that was exploited with indifferent success from 1923 to 1931, as related in THE PORPHYRY COPPERS. Planning for the entire enterprise had been directed from the start by Harrison M. Lavender, who in 1945, succeeded Percy G. Beckett as vice-president and general manager for all of Phelps Dodge's Western mines and smelters. The untimely death of Mr. Lavender in 1952 prevented him from seeing his plans brought to fruition; but in his honor the mine was fit- tingly named "The Lavender Pit" and was so dedicated on August 7, 1954. The Copper Queen Branch operates under- ground mines at Bisbee (production in 1955 was 28,000 tons) ; but, as this volume is concerned only with Porphyry operations, this chapter deals only with the Lavender Pit project, or as the Government knows it, Bisbee East. My reason for going into some detail regarding the floor-price contract is that it is fairly typical of contracts made by the Government in connection with a half-dozen other copper-expansion projects; and, incidentally, with various projects involving other strategic metals. Phelps Dodge did not seek a loan or other financial aid. The only encouragement asked consisted of (a) the privilege of a five-year write-off (commonly called rapid tax amortization)

Jan 1, 1957

By S. R. Elliott

The Spies mine is located in the eastern half of the northwest quarter of section 2443-35, near the village of Iron River, Mich., and is operated by The Cleveland-Cliffs Iron Co. Speaking generally, the jasper hanging walls of most of the deposits in the Iron River district dip at a steep angle and are exceedingly strong, standing without caving, even after mining has been continued for years and after large excavations have been made. The ore is fairly hard and tough and contains no slippage faces. It occurs in large masses, which are often egg shape, with the smaller end down, and can be mined in open stopes without the use of timber. The common system employed in the district is the shrinkage stope, or some modification of it. The Spies system was developed to utilize the advantages of the open-stope method and to avoid the disadvantages of the shrinkage stope. The Spies shaft was sunk to such a depth that the bottom, or third level, was in rock at a short distance below the bottom of the orebody, the shape and extent of which had been previously determined by diamond drilling. This is shown in plan and by the ore contours at the first, second, and third levels in Fig. 1, and in section in Figs. 2 to 7. In order to provide the necessary mills and raises, three parallel crosscuts were driven on 25 ft. centers on the bottom level. Drifts on the second and first levels were driven to the orebody and followed the foot wall in a southerly direction to the end of the ore. In crosscut 3, Fig. 1, raises 30, 40, 50, and 60 were carried up on the foot wall and holed into the second level, and were ultimately carried up and holed into the first level. These foot-wall raises carry the pipes and ladders, provide a means of ventilation, and furnish safe communication to all working places in the stope. From crosscuts 1, 2, and 3, raises were completed to a height of 32 ft., or the elevation of the first sublevel. They were then connected by east and west crosscuts to the main foot-wall raises 30, 40, 50, and 60, shown in Fig. 4. The crosscuts in raises 1 to 5 were then driven west and the

Jan 1, 1923

ASIDE from the John Fritz Medal, in which the Institute participates through its representation on the John Fritz Medal Board, the, Institute itself has five major awards to make annually for excellence in technical papers, as follows The Robert W. Hunt Medal and Prize, The J E Johnson, Jr Award, The Lewisohn Platinum Prize to senior members, and the James Douglas Medal ROBERT W HUNT MEDAL AND PRIZE The partners of Robert W. Hunt established a fund which was presented to the Institute at a fitting ceremony on May 27, 1920, to establish an annual medal and a sum of money to be awarded under the following rules 1 The award shall consist of two prizes, first of a gold medal, second of a sum of money, a certificate to accompany each prize The money prize shall not be awarded to a member over 40 years of age, but under unusual circumstances, both prizes may be allotted to one person provided that he is not over 40 years of age In general it will be understood that the Committee shall award the money prize to the younger men, rather than the medal 2 The awards shall be made not oftener than once a year to that person or persons contributing to the Institute the best original paper or papers on iron and steel The scope of the term "iron and steel" shall be determined by the sub-committee consider¬ing the awards In general, papers dealing with the practical side of the subject have preference over those dealing with the theoretical side in recognition of the fact that Captain Hunt's main contributions to the industry have been in the improve¬ment of production and quality of material. 3 A sub-committee of three to five, including the Chairman of the Iron and Steel Committee, shall be appointed by the Iron and Steel Committee annually to adjudge the award subject to approval 4 The awarding committee shall submit its report to the Iron and Steel Committee at its October Meeting, and the award be certified to the Secretary of the Institute in time to permit the presentation to be made at the Annual Meeting of the Institute 5 The recipient of the award shall be designated "The Hunt Medallist " This prize is administered by the Iron and Steel Committee

Jan 1, 1923

The officers and staff of the Petroleum Division are the servants of the members, and to the extent that the wishes of the members are made known and are practicable they will be carried out. The tentative plans outlined here are in general accord with previous custom, but modified by suggestions received recently from various members. The advice of all members is solicited, and it is hoped that the general expression on matters of policy can soon be facilitated by circulation of a questionnaire. Plans for two mid-year meetings of the Petroleum Division and for participation in the annual meeting at New York were inaugurated at the last annual meeting and are being carried forward as rapidly as possible in the belief that an early start will increase the possibility of finding the best available program material and permit the careful preparation, review, editing, and advance discussion of papers. While a number of papers have already been solicited, both members and nonmembers are hereby invited to submit additional papers, with the assurance that such papers will be given just as favorable consideration as the papers that have been requested. Mid-year meetings will be held at about the same time both in the Mid-Continent and California. The time will be selected if possible to coincide with the visits of President Lovejoy, who expects to be in California the last of September and in Texas early in October. Fort Worth, Dallas and Austin have been suggested for the Mid-Continent meeting. The Pacific Coast meeting will be held at Los Angeles. It is to be noted particularly that a Pacific Coast meeting was waived last year in favor of the annual meeting of the American Petroleum Institute, which was held at Los Angeles for the first time in nine years. It is hoped, and it was the understanding at the time among a number of individuals interested in both organizations, that in view of this action of the Petroleum Division the industry will give more than the usual support to the A.I.M.E. meeting this year. Ultimate Recovery is being considered as the keynote topic for the mid-year meetings. In view of trying financial conditions combined with an exceptionally high current potential rate of production, it is natural that the attention of the industry should be focused upon means of controlling production and reducing cost of operation. It seems that the Petroleum Division of the A.I.M.E., as a professional group, might

Jan 1, 1936

By S. Grinsfelder

Although wildcatting was hampered by the general overproduction and low price of crude, several developments, worthy of note in the history of the petroleum industry in the Rocky Mountain region, were made in 1927. This district records production from six new fields, two of these having been heretofore productive of gas. Deeper pay horizons were found in two other oil fields. In order to facilitate transportation from fields, six new oil pipe lines were completed or in the course of construction at the end of the year, and one line is proposed for 1928. Four gas lines were completed, one was under construction, and one was proposed for 1928. The total production in 1927 in the Rocky Mountain district was 29,591,379 bbl.,' a decrease of 7,771,991 bbl., or 21 per cent., fro111 the previous year. This was occasioned by natural decline and the general curtailment of production and drilling. A review of the development by states follows. Colorado Production from horizons in the Morrison and Sundance at Craig and at Ilrs Dome, and the bringing in of the deepest producing well in the Rocky Mountain district on North McCalluin anticline (Waltlrn) in Jackson County are the outstanding developments for the year in Colorado. In March the Midwest Refining Co.'s Parkinson 21 SD, SW SE, Sec. 22 T p. 4 N R 92 W, Iles Domr, Moffat County Colorado, found gas in sands in the Morrison estimated at 15,000,000 cu. ft., and at 3242 ft. an oil sand was encountered in the Sundance. Initial production from this horizon was 2575 bbl. in this well. This structure previously was only productive of water in the sands of the Dakota group but has been producing shale oil from horizons in the Benton. The second well completed by the Midwest Refining Co., No. 18 SD in Sec. 23 was also productive of gas in the Morrison and made an initial of 300 bbl. from sands in the Sundance. By the end of the year three other wells wrrc nearing the completion stage but none of them indicate that they will be as big producers as the discovery. To date the productive area has

Jan 1, 1928

By T. S. Fuller

VARIOUS phases of the embrittlement of solid copper containing oxygen by the action of reducing gases at high temperatures through the work of many experimenters are familiar to readers of metallurgical literature. In 1900, Heyn1 recorded observations of copper being heated in hydrogen with the development of fine cracks, the result of the formation of steam within the metal through the action of hydrogen on the copper oxide usually found in copper. Archbutt,2 in 1905, published the results of experiments, showing that all oxygen can be removed from copper by heating to redness, for several hours, in hydrogen. Intercrystalline cracks and extreme brittleness developed. Archbutt attributed the brittleness to the reduction of oxides present in the copper. Bengough and Hill,3 in 1910, encountered the now well-known embrittlement at the outset of their investigation and stated in their paper: It soon became evident that the effect of any heat treatment depended largely on the presence or absence of reducing gases in the atmosphere of the furnace, as well as on its temperature. Hence it became necessary to adopt a somewhat elaborate scheme of heat treatment. The authors found embrittlement in separate experiments due to both hydrogen and carbon monoxide and concluded that: "The gases ruin the alloys after being heated to about 650° C. in their presence."

Jan 2, 1926

By John B. Pearse

IN order to get an idea as to the strength of steel rails, it will be well to review the tests to which iron rails have been subjected. In England, Mr. Ashcroft found that the best 80 pound rails broke under a 300 pound weight, falling 15 feet. In Germany the Society of Railway tyfanage1-s determined 011 and have long applied a test of 1000 pounds falling 101/2 feet, as the standard which all first-class iron rails must reach. In this country no inspection nor test is applied, but tests made show that iron rails fro; our most reliable makers, break under a G foot fall of a 1500 pound drop as an extreme test, most of those tested breaking under a far less test; some breaking with less than a 3 foot fall of the same weight. Everywhere where steel has been used, engineers have come to the conclusion that some test is required to show the regularity and strength of the product. As compared with iron, the tests which steel will stand are wonderful. After numerous experiments partially based on the experience of the rail-mill at Graz, belonging to the Southern Railway of Austria, the Society of German Railway Managers fixed upon a test of 2000 pounds falling 138 feet. They found that this test represented the steel which suited their necessities, and also found that with steel of otherwise average purity, this test represented about one-half per cent. of carbon, and made it a rule to take no steel containing under three-tenths of a per cent. of carbon, because it was too soft. They expressed a hope that a harder steel could soon be made tough enough to stand the same test. I n England, a test was adopted of 2240 pounds, falling 15 to 17 feet on the rail on heavy bearings. This test has been found satisfactory under heavy traffic on average road-beds, and has been invariably

By H. Evans, L. A. Hunt

The raw materials used in the blast furnaces at the Geneva Works of U.S. Steel Corp. have a high degree of variability in size-consist and chemical content. To overcome the problems caused by the use of highly variable raw materials in the blast-furnace operation, large blending piles are used. An investigation of the blending system showed that variability was significantly reduced by the use of these blending piles. This paper describes the blending system, the method used to evaluate the effect of the blending system, and the results of the investigation. The remarkable improvement in blast-furnace performance since World War II has been in large measure due to the use of beneficiated burdens to reduce the variation of both chemical analysis and size consist. This practice allows the operator better control of his blast furnace, enabling him to operate more economically and to produce chemically uniform hot metal. Planning for uniformity usually begins during mining by extracting ore from several locations within a pit to produce a final product with a specified analysis. Another approach is to stockpile ores having widely varying analyses in individual piles and then drawing the required amounts from each stockpile to provide a blend with a predetermined analysis. A further improvement in blending procedures is to take ores from several sources, bedding them horizontally in layers and reclaiming by vertical slicing from the blended pile. The last procedure, when properly executed, is one of the best methods for achieving maximum uniformity with highly variable ores. U.S. Steel Corp.'s Geneva Works initially obtained iron ore for their blast furnaces from the Cedar City area of southern Utah. These ores were formed primarily by the replacement of limestone and siltstone formations with solutions containing iron and several other elements. The original iron content of the ores in the ground varied from a high of 70% to practically zero with a minimum acceptable iron content for shipping of 37%. Substantial amounts of silica, calcium, magnesium and alumina were found in the ores along with minor amounts of copper, lead, zinc, nickel, titanium, manganese, phosphorus and sulfur which were sometimes present in detrimental amounts. Iron-to-silica ratios varied considerably throughout

Jan 1, 1968

By Thomas A. Simpson

THE Birmingham red iron ore district in Jeffer-son County, north central Alabama, Fig. 1, is bounded on the northwest by the Warrior and Plateau coal fields and on the southeast by the Cahaba and Coosa coal fields. The area of study includes the ridge and valley between Red Mountain and Shades Mountain, Fig. 2, approximately 70 square miles extending from Homewood in the northeast to Greenwood in the southwest. The district is one of the most important producers of hematite in the United States, with an annual production of about 7 million tons.' The amount of hematite mined between 1870 and 1950 ranged from 6 to 16 pct of the nation's total annual production,' and the iron and steel products from blast furnaces in the Birmingham district supply the entire southeastern section of the country. Most of the mining in the Birmingham district is from slope mines along the outcrop of the ore on Red Mountain, such as Red Ore, Muscoda, Spaul- ding, and Sloss. The Pyne and the Shannon are the shaft mines of the area. The Shannon mine of Republic Steel Corp., in the central part of the area under study, is in Shades Valley at the foot of Shades Mountain. The Pyne mine of Woodward Iron Co. is 2 miles east of Readers Gap in Shades Valley. The hydrology problem has become more prevalent as mining in the area has progressed downdip. An extensive exploratory diamond drilling program is necessary to determine areas where water pressures and abnormal flows are excessive. This operation, added to higher pumpage rates, has greatly increased the costs of ore extraction. In November 1952 the U. S. Geological Survey began a detailed study of occurrence and movement of ground water in the iron mining areas of the Birmingham district. The study is a part of a small-scale but nationwide program to develop data that will be of help to the mining industry in solving mine water problems. The area of the study, in the Ridge and Valley province of the Appalachian system, Fig. 1, is a series of alternate ridges and valleys trending northeast. The principal ridges are Red Mountain, altitude about 1000 ft, and Shades Mountain, about 1100 ft. Shades Valley is between these two ridges, and its lowest point is about 480 ft. Shades Moun-

Jan 1, 1956