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By Thomas M. Dr. Drown

REMARKABLE as have been the direct results of Danks's puddler, there are some indirect and incidental results, which are well worthy of study for their intrinsic value and suggestiveness. The success of Danks's machine is due mainly to the nature of the lining and the manner in which it is attached to the walls of the revolving chamber. Herein lies Danks's merit and good fortune. Given such a lining, and the success of the machine, as far as puddling iron is concerned, could easily be predicted. Other important results have, however, been obtained with this machine, which, though clearly explicable, were, nevertheless, unanticipated. These are the increased yield of bar-iron over the pig-iron charged, and the elimination of phosphorus, which, though not absolutely complete, is yet more decided than in the case of hand-puddling. As regards the increased yield, this is merely what we have a right to expect if we consider the puddling process to consist in the oxidation of the carbon and silicon of the pig by the oxygen of the oxide of iron. That this result is attained, nearly to the extent that the theory requires, in Danks's puddler, and has never been more than partially attained by the most careful experiments in hand-puddling, points clearly to the fact that the contact of the molten pig-iron with the oxide of iron is much more intimate and complete in the one instance than in the other. The action of puddling in Danks's machine may be considered to be twofold first, the removal of the carbon, silicon, and phosphorus of the pig, which is the primary object, and, second, the production of wrought iron direct from the ore, which is entirely an incidental result. Intelligent metallurgists were not long in recognizing in this latter result a fact of deeper import and greater value than the attainment of a perfect puddling process. A new method

Jan 1, 1874

By F. C. Sturges

By definition the word "grout" means a thin mortar, or a kind of plaster or cement, and "grouting" means to fill up or finish with grout. The words "cement," "plaster" and "mortar" mean a substance that is used in a soft state which subsequently hardens. Thus, grouting is the filling of void space with a substance that hardens. Construction cements are the most common substances used, either by themselves or in mixtures, but the term grouting is applied quite correctly when other substances such as plastics and certain chemicals are used. Also, the use of the term grouting to cover the filling of voids with materials that do not actually become hard, such as the flotation tailings used in grouting in the southeast Missouri lead district, should be considered correct, as some stiffening does take place and, anyway, it is a better descriptive term than any substitute. Engineers are interested in grouting because some of the materials with which they must work contain voids, and certain conditions can be improved if these voids can be filled with something solid and permanent. Grouting is done to accomplish several purposes: I. To stop the passage of fluids and gases, 2. To cement materials together to make them stronger, and 3. To prevent consolidation of materials by filling void space with something solid as a replacement for the air and water that could be forced out under load. The construction industry uses grouting extensively for all three purposes. Grouting is used to stop water percolation under and around dams. It is used to control water flow in tunnel driving and in shaft sinking. It is used to improve foundation conditions under civil engineering structures by permanently filling void space and thereby reducing settlement, or by cementing broken rock together and increasing its supporting strength. The oil and gas industry does a lot of grouting, primarily to stop the passage of gases and fluids. The search for oil at increasingly greater depths has meant greater investment per well, and the oil industry has spent large sums on development of improved drilling methods. This

Jan 1, 1949

By Albert F. Schneider

The peculiar conditions under which lead and silver ores are now smelted in Salt Lake Valley, Utah, render it advantageous to make slags that are siliceous and carry a high percentage of lime. The ores treated come from Utah, Idaho, Montana, and Nevada; nine-tenths coming from Utah. These ores are siliceous, and contain but little fluxing material; the iron present scarcely sufficing for the sulphur and arsenic. Formerly ores high in iron were furnished from Cottonwood Canons, but this supply is meagre. The ores from Idaho, Montana, and Nevada are high grade galenas, more or less impure. They generally require a large amount of iron for the sulphur, arsenic, and antimony. In the winter and spring of 1880—'81, we were treating at the Germania Works principally Bingham Canon lead ores and silver ores from Tintic. The former contained 15 to 30 per cent. silica, and only 4 to 5 per cent. iron (generally as iron pyrites); they ranged high in lead and low in silver, and carried more or less alumina; the lead was present chiefly as carbonate. The silver ores from Tintic contained sulphides, and ran as high as 80 per cent. silica. We had been running on a slag approximating 40 per cent. FeO, 20 per cent. CaO, 10 per cent. other bases, and 30 per cent. SiO2, which had heretofore been very satisfactory; but with the class of ores then coming in it was of the utmost advantage to use less iron and more lime, especially as the iron ore (50-55 per cent. iron and 5-7 per cent. silica) cost four times as much as the limestone (50-55 per cent. lime, 3-5 per cent. silica). The large amount of alumina in the slag influenced them for the worse; the addition of lime to the charge helped them, and after many experiments regarding the proportion of FeO, CaO, and SiO2, a slag approximating 35 per cent. FeO, 25 per cent. CaO, 5 per cent. other bases, and 35 per cent. SiO2 seemed to answer

Jan 1, 1883

By G. K. Manning, W. E. Few

WORK on the effect of vacuum heat treatment of 0.040 in. diam sintered and wrought molybdenum wires has been sponsored by the Office of Naval Research at Battelle for the past several years. An electrical resistance furnace' capable of maintaining a vacuum of less than 0.1 micron of mercury at temperatures as high as 4000 °F was used for heat treating the wires. Early in the work, it was found that the introduction of a few microns pressure of oxygen into the furnace resulted in a rapid increase in the oxygen content of the wire specimens and the appearance of a discrete oxide phase. Subsequent elimination of the oxygen atmosphere caused the disappearance of the oxide phase. This was used to determine the solid solubility of oxygen in molybdenum over the temperature range of 2000" to 3000°F.2 It was observed that, with the disappearance of the oxide phase, the wires regained some ductility. Single-phased wires possessed from 5 to as much as 40 pct elongation in 2 in. Later, attention became centered on determining the cause of this wide range in ductility. Wires containing less than 0.002 pct C, less than 0.0007 pct 0, less than 0.0005 pct N, and less than 0.00003 pct H exhibited the erratic ductility noted above. These percentages represent approximately the limit of accuracy of presently available methods of analysis and thus it became apparent that chemical analysis would be of little help in the study. A number of possible explanations for the wide range in ductility were suggested during the course of the work. It was first suspected that variations in the grain size of the recrystallized wire specimens might be responsible. Wire from several lots of material was available. One of these lots tended to develop very large grains when recrystallized, the others all developed an ASTM grain size of 3 to 4 when heated above 2700°F. No correlation between grain size and ductility could be found. It was thought that back diffusion of oil from the diffusion pump might cause contamination of the wire, principally with carbon, but when wires were treated without cooling the cold trap in the pumping system,

Jan 1, 1956

Jan 1, 1920

By H. J. Wasson

Published literature regarding the nation's oil reserve has been largely concerned with the estimated quantities in sight in known producing fields. This proved reserve has never been large in relation to demand. It has been the practice to consider the total future reserve (beyond that in sight within known fields) in the light of the broad potentialities of vast areas of partially explored sedimentary rocks, which are regarded as possible oil territory. Until recently, but little attention has been given to the rate at which the unexplored potentialities may be. converted into the proved reserve classification. To a certain extent, therefore, our contemporary viewpoint on the subject of national oil reserves is characterized by a pronounced contradiction. On the one hand, we measure known reserves as sufficient for only a few years of consumption—i.e., relative scarcity; on the other hand, we are confident that millions of unexplored acres will yield many new oil fields and that countless deeper productive formations underlie many of our known productive fields—i.e., infinite abundance. Of greater significance than the quantitative measure of either of these reserve classifications is the rate at which reserve replenishment must be accomplished in order to maintain an adequate time supply of proved oil reserves. The accumulation of geological data covering broad areas supports the belief that the remaining undiscovered oil reserve is exceedingly large. The distribution of oil in sedimentary formations of practically all ages, from Cambrian to Recent, is suggestive of almost unlimited possibilities; and the relatively small proportion of these possible areas that has been intensively explored in this country is a further index of the probable magnitude of the undiscovered future reserve. The implication that may reasonably be drawn from these observations is that oil, though distributed with less regularity and concentration than its related hydrocarbon, coal, nevertheless is a relatively abundant natural commodity of which the exhaustion appears remote. Final exhaustion of our oil reserve, if not infinitely remote, is a future contin-

Jan 1, 1937

By Ionel Gardescu

IN connection with some of the experiments carried out by the writer on the behavior of gas and oil in a sand reservoir,1 an interesting phenomenon was observed which may throw some new light on the problem of recovery of oil from a natural reservoir. The experiments are intended to show the effect of the surface area of the occluded gas masses, originally present in a reservoir, on the further evolution of gas from the oil and its consequent effect upon the rate of production of oil. The apparatus used in the experimental work is shown in Fig. 1. It consists primarily of a sand reservoir R and a displacement chamber D, which is used to induce small variations in volume. The reservoir and displacement chamber form a unit, and a lowering of the plunger D is equivalent to increasing the volume occupied by the oil and gas in the reservoir. The reservoir was first filled with dead oil and maintained under pressure until it was ascertained that most of the free gas had gone into solution. The volume of free gas present in the reservoir was computed from the coefficient of compressibility of the fluids by means of the dis-placement chamber D, reading to 0.005 c.c. and a special gage J reading to 0.02 lb. per sq. in. The oil was saturated with gas under pressure in reservoir S by circulating the oil for a long period of time through the gear pump B. Subsequently, the saturated oil was circulated through the sand reservoir following the circuit S6, B, S5, R4, the sand reservoir R, R1, R2, F4, F1, back to reservoir S. In the following experiments the sand reservoir R was filled with gas-saturated oil at a pressure of 415 lb. per sq. in. with no free gas present. This was ascertained by. closing off all the outlet valves, and determining the coefficient of compressibility of the system by means of the dis-placement chamber D.

Jan 1, 1932

By W. P. Frey

THE briquet plant of the Lehigh Coal and Navigation Co., at Lansford, Pa., has previously been referred to.1 It has passed. the stage of experiment and now rests,, on a foundation practically and financially sound. The purpose of this paper is to explain how success has been attained, and to set standards for the development of hard-coal briquetting which may eliminate future failures. All the conclusions are based on actual results, avoiding speculation and theory. Up to three years ago, the L. C. & N. Co. used coal-tar pitch as a binder in making hard-coal briquets. The plant operated with a monthly output of 300 to 600 tons and was unable to meet its own expenses. Naturally, no one was satisfied, especially as the ideals of a smokeless briquet were still unrealized. Then came the Dutch oil process, introduced in this country by the General Briquetting Co. of New York. This process uses as binder a small percentage of heavy residue of petroleum, which, being liquid, permits great economy of handling; it also did away with the most objectionable fumes of the former briquets. This oil2 is not absolutely smokeless; heating the fresh fuel to red heat liberates some low-volatile hydrocarbons, yielding a white smoke which is not objectionable. On the other hand, this oil adds to the briquet about 7 per cent. of volatile matter, giving the product a heating capacity equal to that of the best free-burning anthracite coal. The average silt used in the manufacture of these boulets averages 16.5 per cent. chemical ash, corresponding to 12,000 B.t.u. per pound of coal. The Hydrolene used as binder runs about 17,500 B.t.u. per pound, and approximately 7 per cent. of it enters into the mixture, hence 12,000 X 0.93 11,160 B.t.u. 17,500 X 0.07 1,125 B.t.u. Total 12,355 B.t.u. per pound of briquets

Jan 1, 1918

By Robert H. Richards

The group of four papers on ore dreseing read at the Butte meeting, all of them dealing with the recent developments at the Great Falls and Washoe plants of the Anaconda Company, form an extremely important contribution to the subject of ore dressing. It proves the efficacy of the new hindered-settling principles first brought out in a paper entitled Close Sizing Before digging' and later elaborated in a paper entitled Development of Hindered-Settling Apparatus: and it is the first large demonstration on this class of mill that has been made. It must be very gratifying to all mill men to have these papers at hand, charged with careful investigations and results pointing to the conclusions reached; the papers cannot fail to be a great help to every designer of mills and to mill men who are working on this class of concentration. The papers have dealt with their subjects so completely and have demonstrated every point from beginning to end in each case so thoroughly it leaves little for the commentator to say in the way of criticism. Therefore it seems best to him to confine himself to adding a few points of history which he believes will be interesting to the readers. Referring to the paper by Mr. Wiggin, and to the fact that the Richards hindered-settling pulsator classifier was turned down, the writer wishes to say that this classifier was the first of its kind that had ever been introduced, and since that time it has undergone great developments which he believes would overcome the difficulties encountered in the test,. In fact, there was one test made at Great Falls which with the Wilfley tables and vanners brought all the tailings down to 0.36 per cent. copper except the fine slime. Since that time, and since the classifier has been further developed, in one Colorado mill it proved a wonderful amalgam catcher, catching in all

Jan 1, 1914

By Elihu Thompson

The subject of welding by electricity has been so recently and so ably treated by Sir Frederick Brsmwell before the Institution of Civil Engineers* as to render evidently superfluous there-statement on this occasion of many facts and considerations which might be appropriately advanced, had they not been so well discussed in his paper already. The electrical arts grow rapidly in these days—a fact which is strikingly illustrated in the development of electric railways. In

Jan 1, 1891

Discussion of the paper Of ROBERT H. BEDFORD and WILLIAM HAGUE, presented at the Salt Lake meeting, August, 1914, and printed in Bulletin No. 92, August, 1914, pp. 1807 to 1816. W. L. SAUNDERS, New York, N. Y. (communication to the Secretary *) . -Messrs. Bedford and Hague have given us a very interesting and practical paper. No better excuse for such a paper could be desired than the statement made that the expense of drilling. in this mine is one-third of the cost of delivering the ore at the mill. This statement. should be written in red letters, because it applies to a great many mines besides the one referred to and because it is generally true that in a mining plant, as also in papers read before the Institute, more attention by fat is given to the metallurgical side of mining than to the excavation of the ore, and no study of the excavation work is properly made that does not involve a careful inquiry into the merits of the rock drill used. Next in importance to the selection of a good rock drill, in a case where the actual drilling cost is one-third the cost of delivering the ore, is that. the drill should be maintained in order and kept up to its highest efficiency. The best rock chill may run down in efficiency through accidents, wear, or other conditions which are sometimes beyond supervision or control. The machine is usually in the hands of men who know how to get workout of it, not men who know how it works. The best drill runners are not machinists,. but miners. They could not tell you how the valve operates or the principle of the rotation, but they know how to get the work done. A testing machine, particularly the type described in this paper, may he of the greatest value in maintaining a uniform state of efficiency.

Jan 11, 1914

By W. B. Weeks, H. K. Shearer

The year 1937 brought to south Arkansas increased drilling activity and production. Oil production amounted to 12,159,440 bbl., an increase of 1,504,500 bbl., or 14.1 per cent over 1936. This was the largest production since 1931, and the first annual increase since 1925, when the deeper sands at Smackover were developed. There were 177 wells completed during the year, with 103 oil wells, 6 gas wells, and 68 dry holes, an increase of more than 100 per cent over 1936. Of the 56 wildcat wells drilled, 52 were dry and 4 produced oil. Two new fields, one important extension and three minor extensions were discovered. The trend toward deeper drilling is shown by the fact that 97 wells were more than 5000 ft. deep, including 80 over 6000 ft. and 13 over 7000 ft., although the depth record of 7973 ft., made in 1935, was not exceeded. Geological Section Deeper and more extensive drilling during the past few years, not only in south Arkansas but also in adjacent parts of north Louisiana and east Texas, has furnished much important geological information and has brought out some very unexpected facts in regard to structural and depositional conditions in the series of formations laid down in the interval between the end of the Pennsylvanian and early Cretaceous time. It is now evident that an important basin of salt deposition existed in the Arkansas-Louisiana-Texas area, but it is still an open question whether this salt basin was contemporaneous and continuous with the even larger Gulf Coast salt basin extending from Mississippi to Mexico. The accompanying columnar section (Fig. 1) shows the producing zones and names that have been applied to the several subsurface formations, most of which have no outcrop equivalents. This is for the convenience of readers unfamiliar with recent developments, but the correlations and nomenclature cannot yet be considered final. These formations will be discussed in more detail in various papers to be published in the near future.

Jan 1, 1938

By David Baker

When the skip-hoist was first tried as a means of filling the blast-furnace it made a great many enemies and very few friends among furnace managers. This state of affairs continued until the Duquesne furnaces were built, which demonstrated not only the possibilities of a furnace-stack in the way of production, but also the ability of the skip-hoist to charge the materials necessary to produce the large tonnlage obtained. Every furnace manager, who has operated stacks fitted with the vertical hoist and the hand-barrow system of filling, remembers that the momentous question about the furnace, particularly during a good run, was: "Are you keeping her full ?" and many a good run has been spoiled by the furnace " getting away from the men." With the new birth of the skip-hoist this trouble was eliminated ; but alas! Other and more important difficulties arose. The distribution of the stock, the importance of which is never learned until many different ores and fuels have been tried, demanded closer attention. With all the defects of the hand-barrow system, the distribution—When the top fillers were conscientious in carrying out the scheme of filling arranged after thoughtful consideration by the manager—mas above criticism. It is said that the modern skip-hoist, equipped with an elliptical hopper and receiving-cylinder, and discharging over a small bell into the main hopper, will give just as good results as those obtained with hand-barrow charging, but I cannot agree with this statement. I grant, that under very favorable conditions, the mechanical furnace-top will do apparently as well as the

Jan 1, 1905

By J. Th. Erb

The total crude oil production of these islands, which in 1928 amounted to nearly 5,000,000 metric tons—about 36,500,000 bb1.—has again increased in 1929. The figures for 1929 are as follows: Metric ToNs† North Sumatra........................................ 369,930 South Sumatra........................................ 1,236,510 Java and Ceram....................................... 678,787 Dutch Borneo (including Tarakan)....................... 2,793,326 Sarawak.............................................. 759,700 Total............................................... 5,838.253 †1 metric tor1 = 7.36 bbl. on the average. This production, as far as the Dutch Islands are concerned, is owned partly by the Bataafsche Petroleum Maatschappij, the producing subsidiary of the Royal Dutch Petroleum Concern, and partly by the Kolon-isle Petroleum Maatschappij (Standard Oil Co. of N. J.), while that of the British Protectorate Sarawak belongs to the Anglo-Saxon Petroleum Co., Ltd., of London. The increase in 1929 is due partly to more intensive drilling; the rotary system, which enables drilling to be done more quickly and to greater depths than was possible with the percussion system, has come into more general use. Further, considerable extensions have been made to some of the existing fields and several new pools have been discovered, which contributed in no small degree to the increase in production. Of particular interest is the fact that the ('Niam" (Nederlandsche Indische Aardolie Maatschappij), in which the Dutch Government has a large share and which company in 1928 was producing from only two fields in South Sumatra, has discovered a pool in North Sumatra and, moreover, has struck oil on the island of Poeloe Boenjoe near Tarakan (Eastern Borneo). The deepest well still drilling is in one of the fields of the "Niam" and has reached a depth of 2269 meters (7445 feet). Notwithstanding the tropical c1imate and the dense jungle in which most of the fields are situated, the most modern scientific methods are applied in exploration, in drilling, producing and refining.

Jan 1, 1930

By B. B. Cox

The Iraq Petroleum Company, Ltd. continued its systematic exploration and exploitation of the Kirkuk field on a unitized basis. Pressures, gas-oil ratios, oil-water level and oil-gas level remained satisfactory. All wells were produced by flowing and more than two-thirds of the crude was stabilized. The only exports from Iraq during 1937 were from the Kirkuk field. Mosul Oilfields, Ltd., through its operating subsidiary, the British Oil Development Company, Ltd., inaugurated an exploratory program to find lighter oil than the heavy, black, sulphurous reserve proved in the Qaiyarah-Najmah-Jawan-Qasab field. Deeper drilling in this field found a small reserve of 17" to 19" A.P.I. black sulphurous oil in the Pilsner (Upper Cretaceous). Ten structures outside the proved field were tested or were under test at the end of the year. In spite of this intensive program no reserve of lighter oil was discovered. The reserve at Qaiyarah-Najmah-Jawan-Qasab averages 16" A.P.I. with 6+ per cent sulphur from the "continuous limestone" (Lower Miocene, Oligocene, Middle Eocene) and from the Pilsner (Upper Cretaceous). The Khanaqin Oil Company, Ltd., a subsidiary of the Anglo-Iranian Oil Company, Ltd., conducted the normal exploitation of its Naft Khaneh oil field and supplied the local Iraq market requirements. Slightly more than 31,600,000 bbl. of crude was produced in Iraq during 1937. The following table gives the total crude produced by the I.P.C. for export during the last four years. Year 42-gallon BarreL Increase over Preceding Year 1934 7,096,669 1935 27,014,904 19,918,235 1936 29,521,053 2,506,149 1937 31,171,476 1,650,423 " Converted at an average of 7.6 bbl. per ton. Published by permission of the Near East Development Corporation. Manuscript received at the office of the Institute March 11, 1938. * Geologist, Socony-Vacuum Oil Co., Inc., New York, N. Y.

Jan 1, 1938

Lewis, B. LINDEMUTH, ?New York, N. Y.-I would like to confirm Dr. Howe's supposition that a process could be worked out for steel along similar lines. About 1 ½ years ago, F. D. Carney and myself were working on the elimination of columnar crystals which are particularly evident in nickel steel. We discussed rotation and varying speeds of rotation, but figured that with just rotation the steel would eventually catch-up to the motion of the mold and that the desired effect could not be obtained in that way, so we decided to alternate the direction of rotation. We rigged up in ordinary commercial turntable and on the same mounting attached a blast, furnace and mud gun, which is a simple steam cylinder, and mounted an 18-in. ingot mold on the turntable. The turntable had a stroke of about 10° to 12°, with stops at the ends. The steam cylinder would bang the table against the stops so that the stopping was so violent that it would tend to keep the metal in motion when the mold stopped and thus wash away any crystals that would form. We made quite a few interesting experiments; the results of which were that the columnar crystallization was entirely eliminated. At the same time we cast ingots in a similar mold, allowing the molds to remain stationary; these showed columnar crystals of from 2 to 4 in. in depth. The grain structure of the balance of the ingots, which were rotated, was very much finer than the grain structure of the ingots that were cast and allowed to cool slowly. The experiments were made on a 0.35 per cent. carbon nickel steel, which is probably more susceptible to columnar crystallization than any other. I think that the rolling properties and the forging properties of some alloy steels could be very much improved by a similar method, or some commercial method of casting ingots to eliminate this columnar crystallization.

Jan 5, 1919

By C. B. Post, G. V. Luerssen

J. STEVENS*—The authors state that the contamination in the metal was due mostly to the ladle refractories. Did the contamination vary with different brands of refractories or different qualities in the ladle ? C. B. POST (authors' reply)—That would be expected. In our shop we have used a grade of firebrick which is fairly standard. We do use high refractory nozzles to combat this erosion and high refractory sleeves, but there is such a problem when you get a skull in a ladle you just cannot use these high refractory bricks; you rip out the whole ladle getting the skull cleaned up. The acid bricks form a glass, and you can pull the skull out when you do get them. I believe you might find variations among the different refractories depending on how much silicon is in the brick. This determines how much silica is going into the interface between the steel and the brick. Our brick is about 35 pet alumina and 65 pet silica. With a brick of 35 pet alumina in the slag patches new calculations would have to be made. R. PARDEE*—Where can you draw the line in determining the refractories as being a silica refractory ? C. B. POST—More silica than about 50 pet. I think perhaps that is generally the criterion. The brick we use is a good high grade fire brick. T. S. WASHBURN*--With reference to the higher silicon that is recommended as a result of this investigation, is it contemplated that the specified range would be raised to 0.40-0.60 pet silicon, or possibly 0.50-1.00 pet silicon? These higher silicon ranges would affect the physical properties of the steel and consequently there might be some complications with respect to educating the consumers to 'accept this revision of the conventional analysis. C. B. POST—It will take considerable work. Take AMS 6260 as an example. Ordinarily this specification calls for 60 or 75 manganese. Silicon has some

Jan 1, 1950

By H. De Cizancourt

Peche1bronn.—So far Pechelbronn is the only producing district. Figures are given in Table 2 covering the main features of the field, but these figures call for the following remarks: First, Pechelbronn should not' be considered as a single unit, it appears, but as a succession of small oil fields, each of which is affected by very variable conditions. Consequently, certain figures concerning production per acre, production per acre-foot, pressure conditions and thicknesses of oil sands would be so misleading that they have been omitted here. Second, as regards production methods, attention is drawn especially to the fact that 42 per cent of the oil is extracted by the use of shafts and galleries and the remainder by pumping wells. Exploitation, formerly confined to Oligocene sands, has been extended recently to Jurassic and Triassic oil-bearing formations. Gabian.—This small oil field, discovered in 1924, is almost exhausted. Exploitation to date is restricted to three wells. There were no drilling activities in 1933. Exploration.—During 1933, two exploration holes have been started in France. The first, in the vicinity of Lavelanet (Ariége) on the Dreuille anticline, has reached the depth of 2400 ft,.; the second, in the Autun Permian Basin, is drilling at 1300 feet. Northern Africa Morocco.—Drilling operations have been on a large scale in Morocco. In the Gharb district (Souk el Arba area), the deepest well was abandoned in 1933 at 7014 ft. Small irregular productive horizons were encountered in the Miocene at shallow depth, oil and gas showing in the Eocene, but no commercial oil field has been discovered. In the Djebel Tselfat, near Petitjean, a small production of oil was obtained from a Jurassic horizon. In the meantime deeper formations are being explored and a new structure in the vicinity is being tested. In Eastern Morocco, a well is drilling near Taza. Production in Morocco, about 2400 bbl., has not been listed on Table 2, owing to its origin—exploration wells.

Jan 1, 1934

By Laurence Delisle, Aaron Finger

THE alloys formed by the addition of nickel to iron by convelltional metallurgical procedures show physical properties that differ widely from those of the individual metals. The effect of alloying on the mechanical properties is most pronounced in alloys containing between 15 and 25 per cent nickel. The tensile strength of an alloy containing, for example, 20 per cent nickel and 80 per cent iron (with 0.06 per cent carbon), in an annealed condition, is above 150,000 lb. per sq. in.? owing to a martensitic type of transformation, as compared with about 50,000 lb. per sq. in. for pure iron in the same condition. The object of this work was to determine whether the same beneficial alloying effect could be obtained in alloys of iron and nickel prepared by powder metallurgy technique. PROCEDURE Bars and pellets for tension and compression tests, respectively, were made. Two groups of specimens were prepared: (I) by cold-pressing the powders and sintering; (2) by cold-pressing the powders, sintering, repressing and resintering. Raw Materials Nickel powder supplied by Metals Disintegrating co., marked MD-151, was used. A typical analysis of this powder was as follows: sulphur, 0.040 per cent; copper, 0.18; iron, 0.23; manganese, 0.002; magnesium, 0.001 5 ; lead, 0.035; tin, 0.025 ; silicon, 0.08; chromium, 0.008. Electrolytic iron powder supplied by Plastic Metals Inc. was used. A representative chemical analysis for impurities other than gases, supplied by the vendor, gave the following results: carbon, 0.005 per cent; manganese, 0.002; silicon, 0.003; phosphorus, 0.001; sulphur, 0.004; nickel, 0.008. The fractions from these powders passing a 3 2 5-mesh sieve were reduced in hydrogen at 600°C. for one hour, to clean the surfaces of the particles. The reduced powders, slightly caked, were ground in a mortar and screened again through a 325- mesh sieve. Mixing The proper proportions of the powders were mixed overnight on rolls, in glass jars fitted with iron-wire baffles to break aggregates of particles that might form. Pressing All specimens were compacted on hydraulic presses. The pellets were compacted in a cylindrical die, ½ in. diameter. The ratio of thickness to the diameter of the pellets was maintained as nearly as possible at 0.9, as specifed for standard short compression pieces. The tensile bars were made by compacting 30 grams of powder. Their shape is shown in Fig. I. The compacting pressures for the pellets and the tensile bars were:

Jan 1, 1946

By Harmon D. Nine

DISCONTINUITIES in the strain vs cycles to failure (S-N) fatigue curves have been reported for polycrystalline materials by Porter and Levy for copper,&apos; by Benham and Ford for mild steel,&apos; and by Williams and Stevens for 18/5 stainless steel.3 However, the considerable scatter of the points for polycrystalline materials have made a statistical analysis of the data necessary to confirm the discontinuities. By using oriented single crystals of high-purity material and low grown-in dislocation content, the reproducibility has been improved to a degree which makes statistical analysis unnecessary and clearly shows discontinuities in the S-N curves. A recent publication4 reports an abrupt change of slope in the S-N curve for ( 100) axially oriented copper single crystals fatigued in torsion. The reported discontinuities in the S-N curve, along with a different mode of failure in the two branches of the curve, have been interpreted as being due to two different amplitude-dependent mechanisms. Further work on copper single crystals of (111) axial orientation has now been completed which supports the existence of an amplitude-dependent change in the mechanism of fatigue. In the present study torsional-fatigue experiments were performed at room temperature in air on (111) axially oriented single crystals. The crystals were grown and prepared as reported in Ref. 4. Two different methods of growing the crystals also discussed in Ref. 4 produced crystals of two different perfections: Type I with dislocation density of >l06 per sq cm and Type I1 with dislocation density of <l05 per sq cm. In accordance with the accepted hypothesis that crystal flaws are primarily responsible for the scatter of fatigue lifetimes, particularly at low amplitudes, the values for the three lowest amplitudes for Type I crystal are believed to be uncertain. They are marked in braces in Fig. 1. On the other hand, at amplitudes above a surface shear strain (SSS) of *0.003, the data for both types of crystals are in agreement. Most remarkably the S-N curve for torsional fatigue of (111)-oriented single crystals is composed of three segments separated by rather large discontinuities, Fig. 1. Metallographic and X-ray measurements indicate that the lower branch corresponds to the low-amplitude (F) region of the (100) copper single-crystal results as discussed in Ref. 4, and the two upper branches correspond to the high-amplitude (H) region. The lower discontinuity in the (111) S-N curve and metallographic evidence give further support to the hypothesis that different mechanisms of failure operate for high and low strain amplitudes. Reference to the resolved shear stress diagram, Fig. 2, shows that the highest stressed systems in

Jan 1, 1965