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By A. Boltax

The effect of cold work on the electrical and magnetic properties of solution-treated and aged Cu-Fe alloys was studied. The electrical resistivity of solution-treated and of aged Cu-1.7 wt pct Fe samples increased by up to 25 and 140 pct, respectively, follozcing a 55 pct reduction of area. The principle contributions to the increase of resistivity of the solution-treated and aged samfiles are examined. Measurements of the .saturation induction, coercive force, and stacking fault Probability are also reported. 1 HIS paper is the second in a series which examine the behavior of the electrical and magnetic prop- erties of Cu-Fe alloys. The first paper1 was primarily concerned with the effects of thermal treatment whereas the present paper examines the effects of cold work on solution-treated and aged Cu-Fe alloys. The effects of cold work on the transformation of the coherent fcc iron precipitate to the ferromagnetic form2 and the coercive force and remanence3 have already been described, but the unusually large increases in resistivity (up to 220 pct) which occlir with cold work have not been reported previously. EXPERIMENTAL METHOD The methods used for alloy preparation, heat treatment, and electrical and magnetic measurements are described elsewhere.1 The specimens, initially 4-in. lengths of 0.0625-in. diam wire, were cold worked by swaging in hardened steel dies. Following each reduction, the samples were etched lightly in hydrochloric acid to remove surface con-

Jan 1, 1962

By S. Chander

A review of the published literature on the mechanism of depression of sulfide minerals shows that a unified theory is not yet available. Various mechanisms that have been postulated include competition between depressants and collectors to adsorb at the surface sites, creation of thermodynamic conditions nonconducive for formation of a metal collector salt, or formation of a hydrophilic coating on the surface. The hydrophilic coating may or may not effect the adsorption of collectors. In another mechanism, the depressant may participate directly in oxidation/reduction reactions between collectors and sulfide minerals. Examples from the literature highlight oxidation/reduction effects in the depression of sulfide minerals.

Jan 1, 1986

By John F. Sulzbach, Donald K. Walker, John F. Abel

With the increasing military significance of the arctic, the U.S. Army Corps of Engineers' ice- tunneling research program has been instituted to determine the feasibility of excavating large under- ice openings. Such openings would provide for year- around storage of material and housing of personnel, independent of surface weather conditions. This unique ice mining operation has been carried on in the tunnels at Camp Tuto, Greenland, during the summers of 1955, 1956, 1957 and 1958 by the U.S. Army Snow, Ice, and Permafrost Research Establishment (USA SIPRE), Wilmette, Ill. Supervisory personnel for the tunneling projects principally have been civilian mining engineers and mining engineering students from Colorado School of Mines. They have been employed under contract between USA SIPRE and the Denver Research Institute (DRI) of the University of Denver, Denver, Colo. Laborers have been enlisted military personnel attached to the U.S. Army Polar Research & Development Center (USA PR&DC) , Ft. Belvoir, Va.

Jan 6, 1959

By K. E. Brown, A. R. Hagedorn

A 1,500-ft experimental well was used to study the pressure gradients occurring during continuous, vertical, two-phase flow through 1-in., 1 1/4-in. and 1 1/3-in. nominal size tubing. The test well was equipped with two gas-lijt valves and four Mathak electronic pressure transmitters as well as with instruments to measure the liquid production rate, air injection rate, temperatures and surface pressures. Tests were conducted for widely varying liquid flow, rates, gas-liquid ratios and liquid viscosities. From these data, an accucrate pressure-depth traverse was construcred for each test in each of the three tubing sizes. From the results of these tests, correlations have beer] developed which allow the accurate prediction of flowing pressure gradients for a wide variety of tubing sizes, flow conditions, and liquid properties. Also. the correlations and equations which are developed satisfy the necessary condition that they reduce to the relationships approprate to single-phase flow when the flow rate of either the gas or the liqutid phase becomes zero. All the correlations involve only dimensionless groups. which is a condition usually Sought for in similarity analysis but not always achieved. The correlations developed in this study have been used to calculate pressure gradients for pipes of larger diameter than those upon which the correlations are based. Comparisons of these calcuclaed gradients with experimetally determined gradients for the same flow conditions obtained from the literature indicate that extrapolation to these larger pipe sizes is possible with a degree of accuracy sufficient for engineering calculations. The extent of this extrapolation can only he determined with additional data from larger pipe diameters. INTRODUCTION The accurate prediction of the pressure drop expected to occur during the multiphase flow of fluids in the flow string of a well is a wideiy recognized problem in the petroleum industry. The problem has been brought even more into prominence with the advent of tubingless or slim-hole completions which use small-diameter tubing. Many of the correlations which give reasonably accurale results in the lager tubing sizes are greatly in error when applied to small-diameter conduits. Small-diameter conduits are defined as 1 1/2-in. nominal size tubing or smaller. The study of the pressure gradients which occur during multiphase flow of fluids in pipes is exceedingly complex because of the large number of variables involved. Further difficulties relate to the possibility of numerous flow regimes of widely varying geometry and mechanism and the instabilities of the fluid interfaces involved. Consequently, a solution to the problem by the approach normally used in classical fluid dynamics based on the formulation and solution of the Navier-Stokes equation has not been forthcoming. This is primarily the result of the nonlincarities involved and the difficulty of adequately describing the boundary conditions. As a result of the foregoing, most investigators have chosen semi-empirical or purely empirical approaches in an efford to obtain a practical solution to the problem. Much of the previous work in this area was done in short-tube models in the laboratory. A number of problems arise, however, when attempts are made to extrapolate these laboratory results to oilfield conditions where a much longer tube is encountered. In those few studies where data taken in long tubes were utilized, the data covered only a limited range of the variables, and as a result inaccuracies are introduced when the correlations are extended outside the range of the original data. Also, as a consequence of the limited amount of data available for these studies, the effects of several important variables were overlooked. The problem of predicting the pressure drop which occurs in multiphase flow differs from that of single-phase flow in that another source of pressure loss is introduced, namely, those pressure losses arising from slippage between the phases. This slippage is a result of the difference between the integrated average linear velocities of the two phases, which in turn is due to the physical properties of the fluids involved. In contrast to single-phase flow. the pressure losses in multiphase flow do not always increase with a decrease in the size of the conduit or an increase in production rate. This is attributed to the presence of the gas phase which tends to slip by the liquid phase without actually contributing to its lift. Many investigators have attempted to correlate both the slippage losses and the friction losses by means of a single energy-loss factor analogous to the one used in the single-phase flow problem. In an approach of this type, hourever, many of the important variables, such as

Jan 1, 1966

By A. E. Harnsberger

IT is obvious that details such as the physical and chemical properties and methods of heat-treating of the materials mentioned must be omitted in a paper on the subject of materials used in oil-refinery pumps1. Only sufficient identification is given to enable the reader to find additional information from already published data. Also, the subject covers many operating conditions, but only the most important services can be discussed here. To the oil refiner, the pumping equipment is of vital interest. Practi-cally every refinery operation, from the charging of crude oil to a dis-tillation unit to the shipping of refined products, involves some form of pumping machinery. Intermediate refining stages involve a great variety of pumping machinery to carry out successfully the aims of the refinery technologist. Temperatures at which oils are handled vary from -50° F. to 900° F. Pressure may vary from subatmospheric to 2000 lb. per sq. inch. The selection of the proper materials involves a careful consideration of the conditions under which the particular pump must operate. The four most important considerations are temperature, pressure, corrosion, and abrasion or wear. Consideration of temperature "may be divided into three parts: (1) extremely low temperatures of the order of -50° F.; (2) temperatures at atmospheric or slightly above; (3) temperatures from 200° to 900° F. Pressures fall into two groups: (1) pressures reached by ordinary trade pumps of the order of 200 lb. per sq. in., (2) extreme pressure conditions involving pressures as high as 2000 lb. Noncorrosive and corrosive oils can be treated differently. Under the latter falls corrosion in the presence of water, which will occur up to 250° F. The second type of corrosion occurs in high-temperature pump-ing equipment, with temperatures from 450° to 900° F., largely caused by sulfur compounds. There are also other corrosive conditions met with

Jan 1, 1935

By P. H. Turnock, R. D. Pehlke

The effects of mutual interactions between elements on the solubility of nitrogen in liquid iron alloys containing chrormium, columbium, molybdenurn, nickel, or silicon have been determined. The equilibrium nitrogen solubilities in the liquid iron alloys were measured by the Sieverts method. The second-order effects caused by the presence of chrormium, columbium , or silicon in the melt were found to be significant. The solubility of nitrogen in liquid iron alloys containing several alloying elements has also been measured as a function of melt temperature and nitrogen pressure. The heat of solution of nitrogen in microcomponent iron alloys has been found to be a function of the logarithnz of the activity coefficient of nitrogen, irrvespectilje of the composition of the melt. The heat of solution of nitrogen in pure liquid iron was determined to be 1265 ± 450 cal per g-atom of N over the temperatxue range 1600° to 1800°. Sieverts ' law was obeyed for all melt compositions studied in the pressure interval 0.4 to 1.0 atm. The solubility of nitrogen in liquid pure iron and in many dilute binary liquid-iron alloys has been the subject of many investigations. Pehlke and Elliott' made a comprehensive investigation on this subject in which they summarized and compared previous researches. However, the practical application of these solubility studies requires prediction of the nitrogen solubility in the multicomponent alloys encountered in operating practice. The interaction parameter as defined by wagner2 has been used to predict the behavior of a solute in a complex alloy, and a modification of this approach has met with reasonable success in several instances.'1"5 The necessity for extending the nitrogen solubility data on binary alloys is caused by the lack of direct measurements of the solubility of nitrogen in molten alloy steels. A direct comparison between measured solubilities and those predicted for multicomponent alloys based on data in binary systems has been made in only a few instances, and most of these were reviewed by Langenberg,6 who developed a graphical technique for predicting nitrogen solubilities in multicomponent iron alloys. The solubility of nitrogen has also been studied over the entire Fe-Cr-Ni ternary system by Humbert and Elliott.? Both studies compared the solubilities computed from binary iron alloy data with those measured in ternary alloys in the liquid state at 1600°C. Most of the nitrogen solubility measurements referred to above were for iron alloys at 1600°C; thus, the ability to predict nitrogen solubilities in molten iron alloys has been restricted primarily to alloys at 1600°C. Recently, Nelsson8 devised an approximate method for calculating the change in nitrogen solubility in molten iron alloys as a function of temperature, but an assumption of regular solution behavior limits the applicability of the method. Chipman and Corrigan9,10 have developed an empirical correlation. based on the activity coefficient of nitrogen in the iron alloy at 1600°C, which facilitates the estimation of nitrogen solubilities at higher temperatures. This method also has limitations, due to the necessity of calculating the activity coefficient for nitrogen in a multicomponent iron alloy at 1600°C from the nitrogen solubility data for binary iron alloys. The shortcoming of such a straightforward approach to the problem of predicting nitrogen solubilities is the disregard of mutual interactions between elements in a complex iron melt. This investigation was conducted in an attempt to provide a more reliable method of predicting nitrogen solubilities in multicomponent iron alloys. The effects of the mutual interactions between chromium, nickel, silicon, molybdenum, or columbium in iron were studied, using the Sieverts' technique1,7 to measure the effects of alloy composition, temperature, and pressure on the solubility of nitrogen in ternary liquid iron alloys.

Jan 1, 1967

By Evan Just

Government aid, regulation, and participation in the mineral industry are not new; they date back to the time when man first adopted communal living. Even in primitive tribal life, the obtaining of arrowhead or ceramic materials, washing of gold, or mining of copper were specialized activities, under tribal sponsorship. Later, when kingdoms, dynasties, and hierarchies developed, titles to mining properties were held by the sovereign or the state, work usually being done by slaves. Title acquisition through denouncement developed in Europe in the late Middle Ages and spread to the Western Hemisphere with the Spanish and Portuguese empires. Denouncements still recognized the rights of the sovereign in the requirement to pay royalties, which practice continues in many places today. Thus, anyone who views government participation in mineral activity as "encroachment" has no historical perspective. Only in a few countries and for a few generations have private interests enjoyed the right to exploit mineral deposits without the specific consent of the sovereign or without payment of royalty. Governments and the mineral industry have been linked together by other factors. Governments have had special interest in metals and minerals as stores of value and for armaments. Spanish conquests in the New World were energized by the lure of gold and silver. Pursuit of gold led to the American seizure of California in the days of the Forty-niners. The strategic importance of minerals in our own times has called for special steps to stimulate production in national emergencies and to prevent the enemy from acquiring mineral supplies. Our export controls to deny certain minerals to unfriendly countries, purchases for Government stockpile, and subsidies for domestic production are examples. Production regulation by state governments of oil and gas has become a well established routine. In brief, the mineral industry has never lacked aid, regulation, and participation by governments. The entrepreneur who wishes to explore for or develop minerals must deal with governments in most areas before he can begin, because mineral rights are reserved by them. He can proceed through discovery and de-

Jan 1, 1964

By C. K. Leith

GENERAL GEOLOGY OF THE LAKE SUPERIOR IRON-BEARING AND COPPER-BEARING SERIES. THE geology of the Lake Superior region is of general interest, both from an economic and a scientific standpoint. The presence of large and rich iron- and copper-deposits has made a knowledge of the geology of the region necessary for purposes of exploitation and exploration. The ores of the region are contained in rocks of pre-Cambrian age, 'pith for most of the country up to recent years have usually been referred to as « crystalline schists " or " crystalline complex;" and regarded principally as metamorphosed basement-unit upon which the sedimentary rocks, beginning with the Paleozoic, were laid down. In the Lake Superior re¬gion this pre-Cambrian complex presents an unusual variety of rocks with determinable relations. It has been possible, with the large expenditures which-the magnitude of the iron-mining industry warrants, to work out their stratigraphy to a larger extent than has been possible in almost any other area of pre-Cambrian rocks. The real complexity of Lake Superior geology, the confusion of names and the multiplicity of reports covering small parts of the region, are such that interested persons, other than. geologists directly engaged in the work, may well hesitate to attempt to comprehend the geology of the region as a whole. The following paper is a somewhat elementary outline of the geology of the Lake Superior region with special reference to new developments not yet covered in published reports. Geological information concerning the region has been gath¬ered by mining companies, and by the geological surveys of Michigan, Wisconsin, Minnesota, Ontario, Canada, and the United States.. Perhaps in no other part of the country have the mining men themselves spent such large sums in purely geological work. This has made possible the publication of ,reports and maps by the State and Government surveys in much less time and at far less cost than would have been otherwise possible. The. U. S. Geological Survey is the only organization which has covered all of the region on the United 'States side of the boundary, and as its reports include the in¬formation gathered by the mining companies and State organi

Mar 1, 1905

By F. Rosenblum

An on-stream particle size analyzer (PSA) based on the sedimentation principle has been developed to the commercial prototype stage and tested at a concentrator. The current instrument gives a direct reading of the weight % finer than any two sizes, although the capability exists for providing a complete size distribution through the sieve and sub-sieve range. The readings obtained at intervals of about 10 minutes are derived from 0.5-L samples of slurry cut from the monitored stream. The accuracy of the PSA meets the requirements of process control.

Jan 1, 1984

By L. L. McDaniel

DURING the past few years a number of improvements in smelting and power equipment have been made at the Douglas smelter of the FIG. 1.-GENERAL PLAN OF SMELTER. Phelps Dodge Corporation at Douglas, Ariz. In the summer of 1935 work was started on the first unit of a new reverberatory waste-heat boiler plant which ultimately was to furnish steam for a modern high-pressure power plant. A second reverberatory waste-heat boiler unit

Jan 1, 1939

By H. Kenyon Burch

INTRODUCTION THE Inspiration Consolidated Copper Co.'s plant at Miami, Ariz., was designed and built to make possible the profitable working of a low-grade, finely disseminated copper deposit containing 100,000,000 tons of ore averaging 1.64 per cent. in copper. From the-beginning it was evident that the-plant could not, be kept integral but that a break would have to be made somewhere in the flow-sheet, removing at least the concentrator to a site more suitable than any available near the mine. It was finally decided, after considering numerous arrangements, to do the coarse crushing at the mine, to store the crushed ore in a bin from which it could be loaded into railroad cars and to haul it to the concentrator, an excellent site for which was available about 1 ¾ miles from the mine. The original intention was to equip a plant to treat 7,500 tons of ore per clay, but through the acquisition and proving up of additional ore reserves, the introduction of the Ohio caving system, and the excellent results obtained in the test mill (which made it possible to treat a lower-grade ore than had been thought possible) it was evident that a plant of much greater capacity should be supplied. It was, therefore, decided to treat approximately 15,000 tons of ore per day, the duties of the four main divisions to be as follows:

Jan 9, 1916

By R. H. Rice

Turbo blowers for blast-furnace blowing have now been in use for some years, and a review of the experience gained and the present state of progress may be interesting.

Jan 1, 1915

By John A. Emery, Frank G. Snyder

Mining geology has a threefold objective: to guide prospecting for new ore, to evaluate known orebodies as development risks, and to supply the detailed knowledge of ore structures necessary for more economical extraction. The role of geology in exploration is well established. This article will deal solely with orebody evaluation and the application of geology to development and mining problems as practiced by St. Joseph Lead Co. in the southeast Missouri district, which for many years has supplied approximately 30 pct of U. S. lead production. The primary concern of the present discussion is geology in the district, not geology of the district. The southeast Missouri district, locally called the Lead Belt, includes parts of St. Francois, Madison, and Washington counties. The first recorded mining was about 1720 at Mine La Motte in Madison County on surface showings of lead ore. Later discoveries near Bonne Terre, twenty-five miles to the north, led to extensive prospecting and underground mining. To date the district has yielded well over 8 million tons of pig lead, valued at more than $1 billion. By far the greater part of the lead production has come from an area of 50 sq miles, centering Fig. 1-Central portion of southeast Missouri on the city of Flat River, as shown in Fig. 1.

Dec 1, 1956

By G. Don Sullivan

Although the first application of strip mining dates back to 1866, the true origin of today's problem of land reclamation is found in World War II, when the yawning war machines demanded more, and faster fuel production. To meet the new wartime demands, the strip coal mining companies that had been producing coal for the normal needs of industry and commerce during peacetime worked to the full extent of their capacities but were unable to satisfy the voracious demand. To supplement the production of the established mining firms, a host of temporary, make-shift coal strip operations came into being-road contractors, ditchers and foundation excavators, earth movers of every type became strip coal operators. Unfortunately, many were of the here-today-gone-tomorrow category, and showed little concern for the condition of the land after mining. Likewise, the land owners of the mined properties (most of the land was on royalty lease or tonnage contract) showed little concern. Land owners realized from their acreages more income during the war years of coal production than could have been obtained in two or three lifetimes of conventional farming or other land uses. Most of these mined lands were sub-marginal with little productive promise. As a result the wartime stripping produced most of what are known today as "orphan banks" or "abandoned strip pits." It is of these that so much of the present day complaints about strip mine reclamation are being made.

Jan 3, 1967

THE iron and steel industry spent $1,170,000,000 in 1952 for improvements and expansion, with an accompanying rise of 9 million net tons in capacity to 117.5 million tons of ingots and steel for castings. More than $4,600,000,000 has been invested in the seven years following World War 11. An average of $1260 has been laid out every minute during those seven years for an increase in capacity of 25.6 million tons.

Jan 3, 1953

Year of Election 1944 Walter Hull Aldridge, New York, N.Y 1955 Louis S Cates, New York, N.Y 1946 William Fraser (Lord Strathalmond), London, England 1917 Herbert Hoover, New York, N Y 1955 George M Humphrey, Cleveland, 0

Jan 1, 1959

By George Krauss, M. Cohen

The reverse martensitic transfomzation (i.e., the conversion of martensite to austenite on heating) was investigated in Fe-Ni alloys containing 30.5 to 33.5 wt pct Ni. The reversed austenite was found to be sufficiently distorted to exhibit marked differences in mechanical properties and to undergo recovery and re crystallization on further heating. In particular, the yield strength of the reversed austenite was as much as 2.5 times higher than that of the virgin austenite: with five cycles of the direct and reverse martensitic transformation, the yield strength was 2.6 times higher. There was an accompanying decrease in strain-hardening capacity and in stable ductility or uniform elongation. The recrystallization was observed to follow sigmoidal kinetics, but was characterized by an abnormal1y large temperature dependence which was evidently due to carbon segregation at the migrating grain boundaries. Upon recrystallization, the strength Properties reverted to those of the virgin austenite, but the ductility did not fully recover until the annealing temperature was further raised to dissipate the carbon segregation at the grain boundaries. The transformation of reversed austenite to produce second-generation martensite resulted in an unusually imperfect structure, thereby leaditg to additional strengthening. Horlleuer, the martensitic phase was much less responsive in this respect than was the austenite. MOST martensitic transformations are capable of undergoing a reverse transformation back to the austenitic phase on heating.&apos; This reaction, like the direct transformation to martensite on cooling, is usually athermal. In analogy with the Ms andMf temperatures for the martensitic transformation (where M, > Mf), the reverse transformation is characterized by the As andAf temperatures (where As<Af). It is well-known that the finish (Af) of the martensite-to-austenite reaction on heating may occur at a temperature where austenite is not stable relative to other phases in the equilibrium diagram.&apos; Reverse martensitic transformations have been found to influence the properties of the parent austenitic phase in a number of ferrous alloys. The austenite thus produced after one or more reversals is significantly altered in strength, microstruc-ture, diffusivity, and annealing characteristics compared to well-annealed, virgin austenite. The first detailed observations of such phenomena were made by Wasserman3 on an Fe-30 wt pct alloy. He found that the reversed austenite (i.e., austenite formed by the reverse martensitic transformation) was much stronger than the original austenite, and the second-generation martensite (i.e., martensite produced from the reversed austenite) was somewhat stronger than the first-generation martensite. On heating the reversed austenite, recrystallization occurred in a manner similar to that of a cold-worked metal; the Laue spots sharpened and the strength decreased.4 In recent years, Russian workers have shown considerable interest in these reverse martensitic transformations. Most of such investigations5-10 have been concerned with the stabilization of reversed austenite relative to subsequent martensitic transformation, and because of its unusual nature, this phenomenon will be discussed in detail elsewhere." On the other hand, the annealing behavior of reversed austenite and the attendant variation in properties have received little attention beyond the experiments of Wasserman.3,4 Gridnev eta1.,8 in one of the few such studies. followed the hardness change of reversed austenite as a function of time at three annealing temperatures. The marked strengthening of austenite achieved by the reverse martensitic transformation has been referred to as "transformation strengthening" by Wasserman3,4 and as "phase hardening" by Malyshev et a1.7,9,10 to differentiate it from hardening produced by cold working. Both groups of investigators noted that further strengthening of the austenite could be attained by repeated or cyclic transformations, but the first cycle resulted in the most pronounced effect. Evidence of the altered microstructure of reversed austenite has been reported by Maximova and Nikonorova6 and by Edmonson and KO.12 The former found that reversed austenite was much more sensitive to etching than the original austenite, and the latter authors observed a (&apos;ghost" structure resembling martensite in certain areas of the reversed austenite. Enhancement of the self-diffusion rate in reversed

Jan 1, 1962

By William E. Ford, Edward Salisbury Dana

1. Normal Class (1) Galena Type 2. Pyritohedral Class (2) Pyrite Type 3. Tetrahedral Class (3) Tetrahedrite Type 4. Plagiohedral Class (4) Cuprite Type 5. Tetartohedral Class (5) Ullmannite Type Mathematical Relations of the Isometric System 50. THE ISOMETRIC SYSTEM embraces all the forms which are referred to three axes of equal lengths and at right angles to each other. Since these axes are mutually interchangeable it is customary to designate them all by the letter a. When properly orientated (i.e. placed in the commonly accepted position for study) one of these axes has a vertical position and of the two which lie in the horizontal plane, one is perpendicular and the other parallel to the observer. The order in which the axes are referred to in giving the relations of any face to them is indicated in Fig. 85 by lettering them a,, a2 and a3. The positive and negative ends of each axis are also shown.

Jan 1, 1922

Jan 5, 1953