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By A. D. Schwope, L. R. Jackson, K. F. Smith

Burghoff and Blank1 have pointed out that the creep properties of hard-drawn coppers are closely associated with their individual softening characteristics and have further shown that the creep resistance of various types of copper is improved, under certain circumstances, by cold stretching. In the design of certain types of electrical machinery, it is important to have the creep resistance as high as possible; furthermore, short-time creep strength is important since in many cases stresses are large only during warming-up and cooling-down periods. In this paper, data are presented showing the effect of cold work on the short time creep strengths of various types of commercial copper under several conditions. It is shown that trends from short-time creep tests are evident at longer times. Materials Used in the Investigation The coppers used in this investigation were commercial grade and of two basic types, oxygen free high conductivity (OFHC) and tough pitch. Additions of silver in amounts of 15 and 25 oz per ton were added to each of the two coppers. The analyses of these six coppers are given in Table 1. Originally, they started as wire bars 4 X 4 X 54 in. A. square rod was made by hot rolling the wire bars to 9/16-in. rod in 8 passes. This rod was then cold drawn to 0.445-in.-diam rod and annealed for 3 1/2 hr at 1000°F. It was then cold drawn to 0.325-in. rod and again annealed at 1000°F for 3 1/2 hr. Hard square rods were then made by cold rolling to 0.257 X 0.257-in. rod. Soft wire was made from the hard- drawn material by annealing at 650°F for 3 hr. The final rolling was performed using a set of 9-in. grooved rolls revolving at 30 rpm, which produced square wires. Reductions of approximately 5, 20, 30, and 40 pct were obtained using several passes in the same direction for the large reductions. The 5 pct reduction by drawing was accomplished using a steel die having 2 parallel bearing surfaces. The die angle was 7 1/2 degrees and the wires were lubricated with a paste of ceresin wax dissolved in carbon tetrachloride. The speed of drawing was 13 fpm. Since work was done on only two sides of the wire simultaneously, it was necessary to rotate it 90 degrees each pass to insure uniform deformation. The room-temperature tensile properties of the various tempers are given in Table 2. The grain size of the an- nealed 0.257-in. wires was uniform and averaged about 0.035-0.045 mm. Experimental Procedures for Short-time Creep Tests Standard creep-test frames (Fig 1) were used for the testing. Special fixtures were designed to apply axial compressive and tensile loads to the copper wires. The compression specimens were 1 in. long and the ends were ground flat and parallel. The creep in compression was indicated by the movement of reference marks s-ratched on intersliding platinum strips attached to the moving heads of the fixture. The movement was measured with an optical micrometer fitted with a filar eyepiece on which the smallest division was 0.00005 in. The tensile creep specirriens were 4 in. long which provided ample gripping surface for the jaw-type grips. The platinum strips were attached to a one-inch gauge length of the wire and the creep measured as previously described. The single-specimen furnaces were connected to individual power and control sources. The controlling equipment consisted of Foxboro controllers

Jan 1, 1950

By John Fulton

Johnstown is the site of the extensive iron, steel, and wire-works of the Cambria Iron Company. It is situated at the western base of the Alleghany Mountain, 275 miles from Philadelphia, and 78 miles from Pittsburgh. The valley in which the town and its ironworks are located, has an average elevation of 1160 feet above tide water. Johnstown, in its main features, is a modified duplicate of Pittsburgh. It is located at the confluence of the Little Conemaugh and Stony Creek rivers, which, by their union, form the Conemaugh River, just as Pittsburgh is situated at the junction of the Allegheny and Monongahela rivers, which together make the Ohio River. The site of Johnstown is in a cutting through the lower productive coal measures, 500 c feet deep, with steep slopes along the valleylimits, exposing, in sharp-cut terraces, the outcrops of the coal and iron-ore beds; the whole surmounted by the shales and sandstones of the barren measures.

Jan 1, 1885

By John H. Bassarear

By 1968, Cyprus Pima was milling 34.5 kt /d (38,000 tpd) of copper ore using a conventional flowsheet consisting of three stages of crushing, rod milk and ball, mills. A 13.6 kt /d (15,000 tpd) expansion was put onstream late in 1971 using primary crushing, semiautogenous milk, and ball mills. Identical ore is treated in both concentrators. This paper shows the weight and life of each liner for each crusher and each mill over a four year period from 1974-1977. Media consumption is shown for the same period and a comparison is made between the two reduction methods.

Jan 1, 1983

By Milton E. Wadsworth

INTRODUCTION The purposes of this conference are aimed mainly at the treatment of fine or ultra fine particles in terms of beneficiation and chemical processing of minerals. For this reason the discussion on leaching will be confined to processes which treat slurries rather than those which treat a large variety of low and medium grade materials by vat leaching or dump leaching techniques. This eliminates such hydro-metallurgical systems as solution mining from consideration. This discussion will focus predominantly upon the behavior of fine particles as associated with their chemistry in leach reactors. Four major sub-headings may be pointed to as encompassing the major areas in which research and engineering design activity should be directed. These are: 1) generation of fine particles, 2) heterogeneous kinetics of leaching, 3) solution chemistry, 4) engineering design and control of flow reactors. Each of these topics will be addressed briefly in this presentation to illustrate current developments and future needs. GENERATION OF FINE PARTICLES As will be pointed out more quantitatively in the next section the generation of fine particles has great influence upon leaching systems inasmuch as in most cases the rate of leaching is related to the surface area of the particles involved. This is true for acid or base leaching of oxide minerals as well as a large variety of sulfides which have been considered in commercial processes and which have in the case of copper received increased attention during the past decade. Mean particle sizes of slurries vary broadly depending upon the type of grinding equipment being used. For example, in the agitation leaching of uranium ore the slurry typically consists of particles approx-

Jan 1, 1979

By R. W. Raymond

In a paper on the Divining-Rod (Transactions, xi., 411), presented at the Boston meting, in February, 1883,I suggested, among other signs of which the skilled prospector might consciously or unconsciously avail himself in the search for springs of water or mineral deposits, the presence of particular grasses or shrubs, and the general appearance of the flora. There are not wanting, in the literature of our art, indications that greater attention was paid to such signs in ancient days than at present. It is the tendency of a scientific age to ignore, or regard as superstitious, what cannot be classified or explained. But the acute though unscientific observation of earlier times often, doubtless, accumulated facts which it would be worth our while to re-examine. It is highly probable that the mining prospectors of the sixteenth and seventeenth centuries, to go no further back, were close students of nature, and knew, though they could not explain, and, for reasons of private gain, would not communicate, many curious and significant facts. We can generalize better than they could; but for that very reason we are, perhaps, their inferiors in observation. They let nothing pass, because all things were equally significant to them. We take wider views, and miss more. And, no doubt, there still exists among practical millers, prospectors,, hunters, Indians, etc., an unwritten.

Jan 1, 1887

By A. Lubinski, J. E. Hansford

Rotating drill pipe passing through dog-legs suffers fatigue damage due to cyclic bending stresses. Curves of the cumulative fatigue damage incurred in either steel or aluminum drill pipe going through Such dog-legs are presented. These curves provide means for properly planning the rate of angle build-up in directionally drilled wells and allow discarding of drill pipe which has been fatigue-damaged in dog-legs. INTRODUCTION Drill pipe which is subjected to bending as it rotates, experiences a cyclically varying bending stress. If this bending stress is sufficiently large, the drill pipe is fatigue-damaged by each revolution, and ages as fatigue damage accumulates. Drill pipe can be bent intentionally, as in the case of directionally drilled holes, or unintentionally due to unde-sired changes in hole direction caused by variations in formation properties, weight on bit, etc. These changes in hole direction, whether intentional or unintentional, are called dog-legs. The theoretical limits of dog-legs which are permissible before the drill pipe begins to fatigue can be calculated.' However, in wells where the maximum permissible dogleg is exceeded, the concept of cumulative fatigue damage can be used to estimate damage suffered by the drill pipe. This concept has already been used to estimate the cumulative fatigue damage of drill pipe due to drilling vessel roll.' The purpose of this paper is to extend the usage of the cumulative fatigue damage concept to drill pipe in doglegs, and to draw conclusions which may be beneficial in preventing numerous frustrating and expensive drill pipe failures. FATIGUE OF STEEL DRILL PIPE IN IDEALIZED GRADUAL AND LONG DOG-LEGS It is taken for granted that, if necessary, the reader will become familiar with the definitions and concepts which follow by examining the reference cited in each case. For Ref. 1, it will suffce to read only through the section Abrupt Dog-Legs. 1. Concept of the two extreme kinds of idealized doglegs: gradual and long dog-legs and abrupt dog-legs,' 2. Concept of why the bending moment in drill pipe un- der tension is the largest in the vicinity of the tool joint,' 3. Concept of why dog-leg severity which drill pipe can withstand decreases with an increase in tension,' and 4. Definition of the rate of change of over-all hole angle (dog-leg severity)." Figs. 1 and 2 indicate the aging (fraction of life expended) of steel drill pipe passing through a gradual and long dog-leg. Both figures have a left-hand ordinate scale labled Length of Drill Pipe Below Dog-Legs. This scale can be used for cases in which the drill collar weight is applied to the bit and does not contribute to the tension in the drill pipe. It can be used for either 3 1/2-, 4 1/2- or 5-in. drill pipe. This is due to the fact that, if the drill collars do not contribute to the drill pipe tension, then the effect of pipe tension on bending due to a change in pipe size is nearly compensated for by a corresponding change in pipe rigidity. On the other hand, if drill pipe is rotated off bottom, then drill collars contribute to the tension in the drill pipe and this increase in tension is not compensated for. In this case, one of the three right-hand ordinates must be used (the one which corresponds to the correct drill pipe size). In the right-hand ordinates, tension should be understood as the weight in mud of the portion of the drilling string below the dog-leg, minus the weight on bit.

Jan 1, 1967

By E. J. Parkins, H. L. Shergold

The paper is divided into two parts. The first part describes an investigation of the effect of temperature on the conditioning and flotation of an ilmenite ore with a 1:l oleic acid-fuel oil mixture as collector. During conditioning the pulp underwent characteristic changes of flocculation, deflocculation and dispersion which were monitored by measuring the power consumption of the conditioner motor. Optimum flotation results were obtained at the end of the deflocculation period. High ilmenite recoveries were obtained at high temperatures and high concentrate grades at low temperatures. The second part of the paper describes a study of the effect of temperature on the adsorption of oleic acid at the ilmenite/water interface. At high adsorption densities it was chemical and exothermic. Contact angles showed that the hydrophobicity of the collector-coated minerals increased with an increase in temperature.

Jan 1, 1976

By S. Y. Han

INTRODUCTION More than 97% of the total uranium production of the United States comes from sedimentary deposits (1). These sandstone deposits were formed by reduction of migrating uranium-bearing solutions from volcanic silicate rock sources. Such deposits occur in two major forms, either as relatively flat, lens-like deposits or as crescent- shaped roll front deposits. The lens-like deposits are found as discrete masses enclosed in reduced sandstone which is generally surrounded by oxidized sandstone. The roll front deposits are found along crescent-shaped interfaces between reduced and oxidized sands tone (2). In-situ mining of selected sedimentary deposits has proven to be a viable method of extraction and competitive with conventional mining for relatively deep low-grade ores (2). In in-situ leaching, uranium is recovered by drilling injection and collection wells in the ore body, pumping a suitable lixiviant to dissolve the mineral, extracting uranium from the pregnant solution by ion exchange, and finally regenerating and recycling the lixiviant. Even though there is increasing interest and practice in developing the in-situ technique for obtaining uranium values from deeper, lower-grade reserves, there is a lack of knowledge of the basic leaching kinetics and combined transport processes. In-situ leaching operations, in general, appear attractive for the following three general types of deposits (2): (1) low-grade surface dumps or deposits which lie above the natural water table,

Jan 1, 1983

By G. E. Agar

The energy required for dry grinding of phosphate rock in ball and roller mills has been analyzed by the method suggested by Charles and others. The findings are not wholly in agreement with Charles' predictions; but, nevertheless, the method of analysis is shown to be sound. Some of the deviation is probably attributable to the characteristics of a dry grinding system. Many laboratory and pilot plant scale experiments have been made to determine the energy requirements for size reduction. This topic was recently reviewed by Agar and Brown' and it was apparent that very little if any data exists in the literature which permits one to apply the Charles 2-Holmes3 analysis to industrial size systems. More recently, the idea has been put forward that the postulate of comminution by impact used by Charles and others was not sufficient to explain size-reduction throughout the grinding operation. The opportunity exists in the grinding operations of International Minerals and Chemical Corp. (IMC) to analyze the energy-size relationship for dry grinding phosphate rock in both ball and roller mills. This situation arises because the mills are used for custom grinding and make products from 50% to 85% minus 200 mesh. BACKGROUND A correlation of particle size in a comminuted material with the energy expended in size reduction was proposed by charles2 to be of the form

Jan 1, 1965

By C. M. Ball

The magnetic concentration of iron-ores has been so often and so widely studied and discussed among the members of the Institute that any remarks concerning its general importance, from an economic standpoint, would be superfluous; but it is thought that a description of the Ball and Norton ore-separator, designed for cobbing and separating magnetic iron-ores, indicating its essential differences from other machines and the advantages claimed for it, together with some account of recent results obtained in its application to the concentration of such ores, will prove of interest. This machine is the joint invention of Mr. Sheldon Norton, of Hokendauqua, Pa., and the writer, and has been patented in the United States, Canada, and other countries. Of the accompanying illustrations, Pig. 1 represents a longitudinal vertical section of the perfected ore-separator, adapted for separating fine ore, and Fig. 2 the same, adapted for cobbing ore of the size of stove- or chestnut-coal. The two designs are identical in principle, and vary from each other in minor details only. The apparatus consists of a partially-closed chest, having an opening at f, from the feed-hopper, h, through which the ore is delivered to the machine from an ore-pocket or storage-bin provided with means for regulating the flow of ore, so that, when the machine

Jan 1, 1891

By H. Sherman

The general curtailment of activities, so marked in 1931, was continued and intensified in 1932 and although production was maintained at approximately the level of the previous year, 1932 was chiefly characterized by the virtual cessation of drilling in many of the proven fields, a further decline in wildcatting activities, particularly in the Maracaibo Basin, and the relinquishment of large blocks of unfavorably located acreage. A total of only 60 wells was completed during the year of which six were wildcats, while at the same time concessions aggregating approximately. 3,222,000 acres were renounced and reverted to the National Government. The maintenance of production at the previously established level was made possible through the large potential built up by drilling in previous years and by a gradual increase in pumping and gas-lift installations. Towards the end of the year there was a slight but perceptible tendency towards increased drilling in certain of the proven fields. Total production for the year came to 118,076,000 as compared to 118,418,000 bbl. for 1931, while exports amounted to 114,758,000 as against 116,683,000 bbl. in 1931. Table 1 shows production and exports and the average rate per day for the first half of 1932 as compared to the second half. Table 1.—Petroleum Production and Exports in 1932, Venezuela (Barrels of 42 Gallons) Production Rate per Day Export Rate per Day I January-June............ 61,943,000 1 390, 347 July-December.......... 56,133,000 305,071 50,788,000 276,022 Total.........,....... 118,076,000 322,612 114,758,000 313,546 During 1932 the number of active vessels comprising the Lake Maracaibo fleet of shallow-draft tankers was still further reduced, some being temporarily laid up and some transferred to service in other coun-

Jan 1, 1933

By T. M. Williams

DURING the year just ended we have had three great fires in the mines in the Wilkes-Barre district. One at the Empire Colliery, one at the Prospect shaft, and the other at the Baltimore old mine. It is proposed in this paper to give a brief history of the fire at the Empire Colliery, and the methods employed in extinguishing it. The fire was first discovered breaking out in the air-stack, alongside what is known as the " Kidder Plane," about one o'clock on the morning of December 31st, 1873. Subsequently it was ascertained that the fire originated in the return airway somewhere near the steam boiler, located inside the mine, near the head of No. 5 slope. The coal from this slope was hoisted to the shaft gangway, at a point nearly four thousand feet distant from the foot of the shaft. As there were from four to five hundred mine cars hoisted per day from this slope the steam boilers were located at this place. The mines being of considerable extent required a large volume of pure air for ventilation, and no fan having been erected at this slope at the time, the heat from the boiler was made use of to assist ventilation, by conveying the return air from No. 5 slope into the large airway made from these boilers to the surface through the old "Kidder slope" to the stack where the fire was first discovered. The length of this slope or airway was about one thousand feet, with a sectional area of about sixty feet. The quantity of air passing through it must have been over sixty thousand cubic feet per minute

By Joseph Pogue

PRORATION in the petroleum industry has come to mean a method for curtailing the production of crude petroleum by artificial effort, and it is in this sense that the term is employed throughout this paper. Although a contrived curb on supply has been invoked at various times in the past in particular fields and to meet specific situations, it is not until the past few years that this procedure has become general and assumed a dominant role in the oil business. In the sense that we now understand it, proration had its inception in the Seminole area of Okla-homa in 1927, from which time and place the practice spread to include practically all the flush oil fields of the country, especially those of California, Kansas, Oklahoma and Texas. At present there is perhaps no phase of the oil business that commands more attention than proration, nor one that engages more time and effort on the part of executives in the business. The practice of proration, indeed, has not only become an integral part of the policy of most companies and operators, but it has also taken on the aspects of a "movement" involving two schools of thought with considerable feeling, and at times some bitterness, on both sides. In this atmosphere it is difficult to find calm, dispassionate consideration of proration, for most discussions are either vigorous exhortations by its proponents, or else sharp condemnations by its opponents; although it appears that the majority of the industry is clearly "in favor of" proration. It is hoped that this analysis will be taken as an attempt to appraise the movement as an economic force, without bias and without regard to the incidence of the conclusions upon any preconceptions that the industry may entertain.

Jan 1, 1932

By Hsun Hu, R. S. Cline

In an earlier publication1 it was shown that a single crystal of Cu-4 wt pct Al cold-rolled in the (110)[112] orientation was stable up to 95 pct reduction, although the orientation spread was considerable larger than in a similarly oriented and cold-rolled copper single crystal. When rolled to 99 pct reduction, the copper crystal retained its initial orientation and a high degree of sharpness of texture, whereas the Cu-4 pct

Jan 1, 1969

By R. S. Sandhu, S. H. Advani, J. K. Lee, B. L. Aboustit

A comprehensive finite element formulation for thermo-elastic consolidation based on a general variational principle is presented Sample one dimensional problems associated with isothermal consolidation, heat conduct ion, and thermo-elastic consolidation are presented. In addition, evaluations of thermo-elastic consolidation for an underground coal conversion field site are conducted.

Jan 1, 1982

By Ralph H. Sweetser

To control the slag in an iron blast furnace is to control the quality of the pig iron produced (and to a certain extent the tonnage), and to control the whole operation of the furnace itself, including a large part of the cost of production. The character of the slag is the determining factor in the character of the pig iron as to the controllable limits of sulfur, silicon, and, to a certain extent, the manganese; it has an influence on the proportions of combined and graphitic carbons.

Jan 1, 1935

By Ralph H. Sweetser

To control the slag in an iron blast furnace is to control the quality of the pig iron produced (and to a certain extent the tonnage), and to control the whole operation of the furnace itself, including a large part of the cost of production. The character of the slag is the determining factor in the character of the pig iron as to the controllable limits of sulfur, silicon, and, to a certain extent, the manganese; it has an influence on the proportions of combined and graphitic carbons.

Jan 1, 1935

By William B. Plank

THERE are 19 pct fewer undergraduate and graduate mineral engineering students enrolled in the ECPD accredited schools of the United States this year than there were a year ago. The figures are: 8727 this year and 10,674 last year. The entire engineering group in both countries numbers 171,070, as compared with 184,547 last year and 252,250 in 1947-48, the peak year. This is a decrease of 7.3 pct since last year, less than half as much as the decrease in the mineral engineering group. These figures on engineering enrollment for the current year, 195.1-52, in colleges of the United States and Canada were prepared jointly by the U. S. Office of Education and the American Society for Engineering Education. The seriousness of the situation is shown. by the reported demand for 60,000 to 90,000 engineers this year for civilian and defense industries and only 35,800 will graduate next June. Many of the 1952 graduates are subject to Selective Service, having been granted deferments while in college, and ac- [ ]

Jan 1, 1952

By George Otis Smith

That an oil-land law is the most needed item in the proposed program of mineral-land legislation follows from the fact that Congress has never enacted a law really applicable to petroleum and natural gas. The action of Congress in 1897 in authorizing entry of oil lands under the placer law, enacted 27 years before for the mining of gold in surface gravels, was plainly only makeshift legislation. Naturally the provisions of this placer law with its requirement of discovery as a prerequisite to location are nothing less than absurd when applied to petroleum deposits hundreds or thousands of feet beneath the surface. Other reasons which render oil-land legislation an urgent necessity arise first from the large acreage of lands believed to be valuable for their deposits of oil and gas and therefore withdrawn by Executive order from all entry pending the enactment of . an appropriate law for their disposition—a withdrawal that has been specially ratified by Congress in the case of one State, Utah—and second from the exceptional importance of this resource to the nation, the large industrial worth of petroleum, and indeed its paramount value to the navy, not being suspected 17 years ago when Congress last legislated upon this subject. Mineral land of this type is also well adapted to serve for purposes of illustration in discussing the general principles that demand recognition in legislative reform. Most of the issues involved in the consideration of oil-land legislation are clean-cut, and essential differences of opinion will be seen to be based upon radical divergence in economic theory rather than upon conflicting views concerning unimportant details. For the last five years or more the geologists of the Federal Survey have discussed this subject and prepared memorandums and reports on the various bills introduced in Congress. Most of the provisions suggested in the present outline have been under consideration at one time or another during that period, and many of the statements which follow can be said to represent the consensus of opinion among those of us who, both in the field and in the office, have given special attention to the public oil lands.

Jan 1, 1915

1. Healthy and active Local Section or¬ganizations are vital factors in promoting the vigor and growth of the Institute. 2. Activity on the part of Local Sections should be recognized and stimulated by appropriation of funds from the Insti¬tute's treasury; and these appropriations should be as large as is consistent with the relative needs for other activities. 3. As between different Sections, the amount of such appropriations should be based primarily on the extent of activities as reflected in the number and character of meetings held and the attendance of the members at such meetings. 4. In making a request for funds for any year, the officers of a Local Section should submit a report on the printed form approved by the Directors at their meeting on November 19, 1937. 5. A standing Committee on Local Sec-

Jan 1, 1944