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By AIME AIME

OVER-ALL operations of the oil industry, as measured by production of crude oil and consumption of products, are almost exactly of the same magnitude as a year ago. Does this mean that the great oil industry has been undisturbed by the war? Has this industry, so vital to the prosecution of the war and to the maintenance of our way of life, been unaffected in its operations? No indeed - changes within the industry are great. It has been called upon to revamp its trans¬portation methods so as to move about one fourth of the total amount of crude and refined products by railroad tank car instead of by ocean-going tankers. Its fundamental internal economy, based on maximum gasoline yield from a barrel of crude, has been relegated to memories of the past. Rationing of oil products, which has been forced upon us in face of an abundant supply, is not only disagreeable medicine but is in itself completely disruptive to the marketing end of the-business.-

Jan 1, 1942

By J. H. Frye, R. M. Treco

One of the chief hindrances to an understanding of the hardness of solid solutions is the sparsity of suitable hardness data. There is great need of a large body of hardness data obtained from many different alloys of high purity by identical testing methods and corrected to correspond to a single grain size. A considerable amount of such data has been obtained by means of the Meyer analysis on copper-rich and silver-rich solid solutions. There are enough of these data to permit comparison of numerous alloys at equal solute concentration in these two solvents, but only in a few cases is it possible to construct hardness-concentration curves for any given alloy. Therefore additional hardness work on most of these alloys is desirable. The primary solid solutions of silver with cadmium, indium, tin, or antimony as solute are of special interest, since all elements are from the same period of the periodic table and since, as shown previously,l the hardening effect of equal percentages of these solutes is proportional to the lattice expansion produced by them. This paper presents the relation between hardness and concentration in the silver-antimony system from very dilute to nearly saturated solutions of antimony in silver. Experimental Procedure Alloys were made from silver, 99.99 per cent pure, and antimony, 99.975 per cent pure. Silver and antimony were placed in graphite crucibles that had an ash content of less than 0.7 5 per cent. These metals were melted and allowed to solidify in a vacuum, which, after melting was corn- . plete, was usually equivalent to 3 mm. of mercury. A high-frequency furnace was used. The ingots so obtained were worked and annealed to lessen segregation and to control grain size. Annealing was done in evacuated and sealed glass tubes. Hardness measuremeuts on specimens from these ingots were by means of the Meyer analysis.394 Using a 4-mm. ball, impressions were made under seven loads from 25 to 400 kg. The diameter of impression made under each load was measured. This enabled calculation of the constants in the well-known formula of Meyer. L = adn where L = load, d = diameter of impression, a = a constant, n = a constant The Meyer hardness is defined as P = L/i(1/4pd2) or P = 4adn-2/p Meyer hardnesses corresponding to d = I and to d = 4 are of especial interest, since the first corresponds to comparatively slight 'plastic deformation and the second to the maximum plastic deformation producible by penetration of the ball. These

Jan 1, 1945

By J. A. Holmes

SHUTTING-IN the Rangely gas well was an interesting problem because of the high rock pressure and the volume of gas developed, as well as the difficulties encountered. After nearly a week's open flow, the rock pressure was 1275 lb., which corresponds with a 2950 ft. hydrostatic head. The volume of gas was between 45,000,000 and 50,000,000 cu. ft. per day. The Rangeley oil field, which now has a daily production of 100 bbl. of shale oil from shallow depth, lies approximately 100 miles north and 30 miles west of Grand Junction, Colo.; not far from the Utah line. The, well we are considering was drilled on the apex of a large clearly defined. Structure1 in the SE.1/4 sec. 30, T. 2 S., R. 102 W., and entered the gas sand at 2954 ft. on March 2, 1925. The condition of the well at the time the gas was encountered was as follows: 20 ft. of 20-in. conductor cemented with ten sacks at 40 ft. The 15 1/2-in. casing was pulled when the 12 1/2-in. was cemented. 1166 ft. of 12 1/2-in. casing, cemented with fifteen sacks. 2531 ft. of 10-in, casing, cemented with ten sacks; neither the 12 1/2-in. nor the 10-in, casing shut off water but they were cemented for protection. 2938 ft. of 8 1/4-in. 36-lb. casing, hanging on a spider in the collar with a forged-steel, high-pressure bradenhead between it and the 10-in. casing. An 8 1/4-in. drilling, or master, gate and a control head were in place on the 8 1/4-in. casing, and all was in readiness for the bringing in of the well.

Jan 1, 1926

By Charles Schwab

WHEN I leave this life, as an employer of labor there is no one thing that I want so much to be engraven upon my monument as the fact that I have been one of the men who have worked, whether with my brains or my hands, for the advance-ment of industry in the United States, and to be regarded, as I should like to be regarded by labor with love and kindly remembrance for our years of association. In my relationship with my employees, I have always contended that every man should be paid for what he does. I will not employ or be associated with any kind of labor of which the organization insists that a man shall receive a fixed sum of money for his day's wages, however poor or good his day's labor may be. What applies to the common laborer applies equally well to the management, the brains of an industrial establishment. I have always thought of industry as a three-legged stool, with capital, management and labor as the legs. All three legs of that stool must be there before that stool can stand up. If you take any one of those legs away, it is going to topple over. The. three must stand together for successful business accomplishment. I believe that a man who has his labor to sell, to put it plainly, has just as good a right to bargain for the best price for that labor as those who employ him. It is a perfect right for him to do so. If the government of our United States is right, our method of handling labor in our Bethlehem plants is right because it is representative and democratic. We have our labor elect delegates; elect representa-tives from their own ranks, who shall meet frequently. That constitutes, as. it were, the House of our great Congress in Washington, the industrial house. We have our management, who represent the Senate, who meet independently. Working men have learned to express their views freely as to whether they are treated fairly and whether conditions are right or wrong.

Jan 12, 1922

By Henry M. Otte, Ralph P. I. Adler

The changes of line position and integral line breadth in the X-ray diffraction pattern of a polycvys-talline Cu-30Zn tensile test piece, incrementally loaded (and unloaded) up to fracture, have been an-alyzed in detail. The stacking-fault probahility, cv, increased linearly with increasing strain, E, wheveas the effective domain size, De(hkl), decreased with decreasing E-1 Over the greater part of the stress-strain curve the rate of work hardening was essentially constant (about 86 kg per sq mwz), and could be correlated with the slope of stage II of the single-crystal stress-strain curve. Consequently the theories of work hal-dening (particularly those parts relating to stage 11) as developed by Mott and Hivsch and others could be applied to the observations made on the polycrystalline brass. A relationship of the form Aa = Aao - MhklEhkl between the change, Aa, in the extrapolated lattice pararneter and the rvns strain, Ehkl, was derived and found to fit the results acceptably well. From this and other relationships developed in the papev it was estimated that the equilibrium stacking-fault energy of Cu-30Zn was between 8.4 and 12.5 ergs per sq cm, in fuirly close agreement with the (corvected) value obtained by Howie and Swann (1961)43 using transmission electron microscopy. The theory of work hardening in the jorm developed and recently presented by Hirsch (1964)3 successfully described all the pvesent observations. In order to test certain aspects of the theories of work hardening, as developed by Mott,1 Hirsch,2,3 Seeger et el,4-7 and others (for review see Nabarro, Basinski, and Holt8), several recent investigations have been concerned with relating the dislocation density, p, with the shear stress, 7 (and strain, y), applied to the specimen. The results of these investigations have shown that the square root of the dislocation density appears to be linearly related to the applied shear (or flow) stress for fcc as well as bcc metals and alloys. Furthermore, the relationship appeared to apply not only to the deformation of poly-crystalline specimens, but also to stages I and I1 of the deformation of single crystals. An expression of the form has thus come into wide use. Here b is the Burgers vector for a total dislocation, G is the shear modulus, and 70 and q are constants. A review9 of available values of q shows it to have values (at room temperature) in general between 0.3 and 0.6. Forms of Eq. [1] can be deduced from, or predicted by, the current theories, and the various constants adjusted so that they are compatible with the experimentally found value of q . No unique relationship has yet been found between the dislocation density and the applied shear strain. There are several serious objections to the use of Eq. 11]. In the first place, it relates the shear stress to the density of the dislocations without regard to their arrangement, type, or distribution; the significance of the relation may therefore be justly questioned.5 In the second place, the values of the experimental quantities usually substituted into Eq. [11 are those of the applied shear stress and the total dislocation density measured after unloaditzg. The dislocation density value that should in fact be used is that for the mobile dislocations present in the specimen when under the applied load.* Finally, in cases where the values used for p, the dislocation density, are those obtained by electron microscopy, p is subject to considerable error,' both systematic and random. The corrections to be applied are still controversial. Dislocation densities can also be measured by etch-pit and other techniques,'' each having their specific limitations. An objective of the present investigation has been to obtain information about the dislocation configyration and distribution by analyzing the changes in the position and shape of X-ray diffraction profiles as a function of deformation. The X-ray techniques employed, also open to criticism, have certain advantages, however. Thus, although the X-rays diffract only from the surface layers to an effective depth of about 20 p, the measurements can be made while the specimen is under load. The value of the dislocation density obtained by the X-ray method is also subject to errors, which are different from those of the electron microscope. Though a considerably larger volume of material is sampled by the X-rays, thereby reducing some of the statistical errors inherent in the electron microscope data, the information obtained is less detailed and is dependent on the method of analysis used to obtain a value for the dislocation density. Nevertheless, important observations can be made because the aforementioned advantages outweigh some of the limitations. In the present paper the X-ray method is briefly described and applied to a brass specimens deformed in tension. The results are then discussed in terms of some of the current concepts of work hardening. 1) EXPERIMENTAL PROCEDURE Details have already been extensively published elsewhere11-14 and therefore will only be dealt with briefly here. 1.1) Materials and Specimen Preparation. Commer-

Jan 1, 1968

By R. S. Dean

REQUIREMENTS for war materials have led to large scale experimentation upon metallurgical innovations. It is of interest to inquire what this may contribute of permanent value to our existing technology, as innovations adopted during war are apt to be discarded promptly at its end. This is because utilization of substandard ores usually requires a new technology for ore treatment, and a new use-pattern for employment of the products. Thus two very different problems are involved: first, devising a process; then, adopting its products by industry, with readjustments of the use-pattern if necessary. A new process may be as good or better than an old one, but the readjustments required for use of its products may prevent its general adoption if this implies scrapping existing plants and investing much additional capital. Metallurgical innovations are of three kinds: I. The use of substandard material in processes already established; 2. The grading-up of substandard material to render it more suitable for established processes; 3. The adjustment of technology and use-pattern to the raw materials that we have.

Jan 1, 1945

By R. L., Fullman

During the past year there have been a number of significant investigations that have furnished evidence on the driving forces governing grain growth and on the role played by boundary impurities. Thus Burke has shown that in high purity alpha brass the rate of grain growth in the earliest stages is approximately inversely proportional to the existing grain size. This relation agrees with one derived by Zener assuming that surface energy was the driving force in grain growth. Also in confirmation of the surface energy hypothesis, Burke found that growth virtually stopped when the grain boundaries or even only the grain corners were melted.

Jan 1, 1949

By Leonard Grimshaw

THE idea of bonding two dissimilar ferrous metals, and making use of both, is an old one. Tips have been brazed onto tool shanks for many years. The bonding of larger pieces to form whole bars and sheets has also been accomplished, but has received little attention in the technical literature, although a number of patents have been issued covering various methods for its accomplishment. There are three main motives behind the manufacture of composite steels. One is that the physical properties of one steel may supplement those of another; a useful, but at the same time, hard, brittle steel may be backed by a soft ductile one, or a stainless steel may be backed by a steel possessing greater strength. Another motive is direct lowering of cost; an expensive steel may be backed by a less expensive one, bringing down the cost of the piece as a whole. The third motive is an indirect lowering of cost, as when a useful steel is backed by a steel that is easier to machine, so that machining cost on a finished product is lowered considerably. Often more than one of these motives lead to a decision to use a com-posite steel.

Jan 1, 1936

By F. S. Crawford

IRON and copper are mined in the Lake Superior district. The iron mines of the district have the best safety record for that industry in the country as a whole, while the copper mines of the district rank second in two of the four years recorded (Table 1). In Utah copper comes mainly from open-pit mines, which enables that state to lead easily in safety. All of the Michigan production comes from deep under-ground workings. About 60 per cent of the iron miners in St. Louis County, Minnesota, are employed at open-pit mines; this favorably affects the combined open-pit and underground accident-frequency rate, as this county pro-vides most of the Minnesota-mined iron ore. In Michigan, however, there are few open-pit mines, the bulk of the production coming from underground mines, while all of the Wisconsin production, just across the state line from Michigan, is from underground mines. In spite of the fact that fewer mines in Michigan use the safer open-pit method, the iron-mining industry of that state maintained a consistently low record from 1931 to 1934; however, it was many points behind its nearest com petitor, Minnesota, with its much greater production from open-pit mines.

Jan 1, 1939

By L. D. Hall, D. R. Mash

The paper presents the results of experiments on the anelastic. behavior of gold, as manifested by grain boundary relaxation. Two grain boundary internal friction peaks are found for 99.9998 pct Au. It is found that the peaks are associated with primary and secondary recrystallization. However, the existence of two discrete peaks cannot be explained on the basis of grain size and shape alone. It is suggested that grain boundary stability, as determined by orientation, plays a role in the observed effects. EVIDENCE for the viscous behavior of grain boundaries in metals has been presented in recent years by several investigators, based upon studies of various anelastic effects, especially internal friction. KG1 has contributed greatly to this field, having put forward a coherent body of evidence for stress relaxation by the viscous intercrystalline flow mechanism. In this connection, he has made extensive use of pure aluminum (99.991 pct) as the test material, although he has also studied other metals and alloys, including pure iron (Puron).² Rotherham, Smith, and Greenough³ have studied the internal friction of pure tin, interpreting their results in a manner similar to that of KG. In view of the importance of such studies in shedding light upon the fundamental structure and behavior of the grain boundaries in pure metals, it appears that the use of a very pure test material which is inert to its environment should provide useful information on anelastic properties and the source of such behavior in pure metals. The present work was carried out on spectrograph-ically pure, 99.9998 pct Au, free of all impurities except for a trace of silver, estimated to be present to the extent of about 0.0002 pct. The term "pure gold" will hereafter refer to this very pure material. Gold of commercial purity, 99.98 pct, was also studied to observe the effects of small amounts of impurities. A pure gold "single crystal" specimen was also tested for comparison. The variation of the internal friction and rigidity modulus as a function of temperature was determined by means of a torsion pendulum apparatus employing extremely low stress amplitudes and a frequency of vibration of the order of 1 cycle per sec. A 12 in. length of 0.031 in. (20 gage) gold wire formed the suspension element. The apparatus was similar to that described by Ke.l The test procedure and the basic requirements to be met for obtaining useful experimental data by this method have been given elsewhere.1,2 It should be made clear that in all of the experiments to be described, the internal friction and rigidity were independent of the amplitude of torsional vibration. The semilog plot of amplitude of vibration vs ordinal number of vibration was a straight line. This was carefully verified for each internal friction measurement. The linear variation shows that the internal friction was independent of stress; i.e., that the specimens were not being cold-worked during testing. The reproducibility of the internal friction curves, which were obtained by cyclic heating and cooling, indicates that the gold was unaffected by its environment during the tests. The measure of internal friction adopted in the present study is the conventional "logarithmic decrement," defined as follows: log. dec. = l/n In A0/An [I] where n is the number of cycles or vibrations; A,, the initial amplitude of vibration; and An, the amplitude after the nth cycle. When the logarithmic decrement is small, the shear modulus, G, of the wire is proportional to the square of the frequency of vibration provided the length and radius of the wire are kept constant. A plot of frequency squared vs temperature gives the following ratio:' This expresses the fraction of the stress which has not been relaxed at a given temperature. Gr and Gv are the relaxed and unrelaxed moduli, respectively. The frequency of vibration in the polycrys-talline specimen is fp, and the frequency of vibration of a single crystal is f8. This latter quantity is obtained simply by extrapolating the linear, low temperature portion of the curve of frequency squared vs temperature for the polycrystalline specimens. The theory of viscous grain boundary stress relaxation as demonstrated by the anelastic behavior of metals has been discussed in detail by Zener4 and need not be reproduced here. Experimental Results Initial measurements of the internal friction of pure gold were carried out on specimens which had been drawn with no intermediate annealing, resulting in a material which had undergone approximately 99 pct reduction of area in final processing. Annealing was then carried out at successively higher temperatures starting at 400°F for 1 hr and proceeding in this manner to as high as 1600°F in 100°F intervals. After each annealing treatment an internal friction and rigidity vs temperature curve was obtained over the range from room temperature to the particular annealing temperature. The resulting internal friction curves did not exhibit well defined maxima (peaks), but rather several fairly flat

Jan 1, 1954

By A. Grant Elliot, H. W. Lavendel

qualitative picture has been developed to describe the oxidation behavior of TaSi2-coated tantalum and CbSi2-coated columbium. These systems have a significantly lower inherent oxidation resistance than MoSi2-coated molybdenum does. This stems primarily from the fact that Ta2O5 and Cb2O5 are nearly as stable thermodynamically as SiO2, whereas MoO2 or Moos are not. Further, diffusion of silicon in the Ta- and Cb-Si system is considerably slower than in the Mo-Si system. These ,factors prohibit the mechanism of selective oxidation of- silicon which accounts for the oxidation resistance 01- MoSi2-coated molybdenum. The silicide can be stabilized by adding suitable Modifiers which increase the thermodynamic stability of the silicate formed during oxidation. Modifiers, such as aluminum, can be inroduced into solid solution in the coating. in controlled amounts through proper selection of the source in the pack cementation process of coating fov~rzatiorz. Addition of aluminum to TaSi2, coatings on tantalum was effective in moderately increasing the oxidation resistance. EXTENSIVE experimental work and analysis have established the nature of the oxidation behavior exhibited by MoSi2- and MoSi2 -coated molybdenum-base alloys, and defined the conditions for maximum protection against oxidation of the substrate.'-* The oxidation resistance of MoSi2 in the temperature-pressure range of 1100°C-PO2 > 10-5 atm to 1900°C— PO2 > 10-1 atm is due to the formation at the surface of a continuous film of SiO2 which results from selective oxidation of silicon. Under the prevailing kinetic conditions, this film is stable toward the molybdenum silicide with which it comes in contact. Initially molybdenum oxidizes also, but it forms volatile species. SiO2, however, nucleates and grows as a condensed phase. Once a continuous film of SiO2 has formed, the oxidation rate falls to that observed for the oxidation of pure silicon indicative of diffusion through the oxide film as the rate-controlling mechanism. This oxidation behavior is of course highly dependent upon temperature and oxygen pressure. Bartlett and Gage13 and Bartlett, McCamont, and Gagelb define precisely this dependence in terms of the oxygen partial pressures and silicon diffusivities required to support a stable SiO2 film. At low temperatures (near 500°C—the "pest" region) silicon diffuses too slowly to be selectively oxidized. Hence, molybdenum and silicon oxidize readily in proportion to their stoi- chiometry. At high temperatures and low pressure, SiOz dissociates to form volatile SiO(g), and a protective film cannot be maintained. Application of the MoSiz/Mo system is limited to temperatures below 1900oC, the eutectic between MoSi, and MO5Si3.5 The oxidation behavior of MoSi2-coated molybdenum is essentially the same as that outlined above with the exception that the MoSi2 is not in equilibrium with the molybdenum substrate. At the temperatures under consideration silicon will diffuse rapidly into the molybdenum eventually converting the coating to MosSi3.4 The rate constant for subsequent decomposition of Mo5Si3 into Mo3Si plus silicon, and/or the diffusivity of silicon through Mo3Si then becomes low enough to allow active oxidation of both molybdenum and silicon with subsequent degradation of the specimen. A stable silica film can be formed but at temperatures and/or oxygen partial pressures higher than those required with MoSi2 present as a source of si1icon.l, 4 Because of the similarity between the silicides of molybdenum and those of columbium and tantalum one would expect similar oxidation behavior for coatings in the respective systems. This is not entirely the case, however, as shown by the experimental results reported herein. Regarding tantalum and columbium disilicide coatings on tantalum and columbium substrates, respectively, the oxygen arriving at the surface of the coating partitions itself nearly equally between the metal and the silicon, and a two-phase oxide layer (Me2O5 plus SiO2) is always formed. The diffusion of silicon in the tantalum and columbium silicides is relatively slow, compared to that in the molybdenum silicides, which further enhances this equipartitioning of oxygen. Thickening of the coating during service by inward diffusion of silicon into the substrate is correspondingly slow, and the effective thickness of the coating at the roots of cracks and defects is only slightly changed providing high probability for premature coating failure. Furthermore, the SiO2 glass that is generated is not thermodynamically stable with respect to the coating. The metal silicide tends to reduce the SiO2 liberating either free silicon or SiO. The situation can be improved by suitably modifying the coating such that the stability of the protective glass which is generated during service is increased. Thus, selective oxidation of silicon and the modifying agent will occur, and the silicide coating will not tend to reduce the oxide layer. Modifying agents can be introduced into the coating by the pack cementation process. Using sources containing the modifier at controlled chemical potentials allows control of the coating composition. Partially substituting aluminum for silicon in TaSi2 coatings by forming a Ta(Si,Al)2 solid solution was effective in moderately increasing the oxidation protection.

Jan 1, 1968

By Clyde E. Williams

IN planning a postwar program for manufactured products, it is essential that the bases for the plans be wisely chosen. First we must make certain assumptions as to the war's ending. Let us assume: (1) complete victory by the United Nations, (2) peace terms that will ensure the direction of the economy of all nations of the world toward peaceful pursuits, and (3) an early ending of the war, that is, before the nations of the world, excluding the enemy, are near the point of physical and spiritual exhaustion. Thus, our manufacturing plants and transportation facilities will still be in good shape. The plants and transportation facilities, as well as the cities of a large part of Europe, however, will be badly crippled. The rich mineral and other raw material resources of the world, little of which was under control. of the Axis powers before the war or will be after the war, will not be used up. Control of these raw materials, or at least an important part of them, will remain in the hands of the strong peaceful nations.

Jan 1, 1943

Robert W. Hunt, Chicago, Ill.:—It has been my good fortune to know of this development of Mr. York's for some time, and I think he will permit me to say that this is not the first demonstration that he has made of his method for rolling difficult shapes, and which, as he has stated, had in the past been regarded as practically impossible. I have good reason to know that Mr. York has been successful on other lines, because I myself went through a period of professional disrepute for having reported favorably on his methods, which received discredit up to the time that it was practically demonstrated that his claims were true ones. Years ago Mr. York built a mill at Duluth, Minn., for the production of structural shapes, and notably of what might be called balanced beams—beams that did not have flanges of restricted width. His scheme was to produce beams with flanges so wide that they could be used in place of built-up beams. The mill, of course, went through the difficulties that such a mill would have to encounter. I mas called upon to make an examination of the property and report. These beams were rolled on a universal mill—a mill which would admit of various-sized sections without change of rolls. I was convinced that Mr. York could do it, and I so reported. Having received condemnation and ridicule for having taken that position, later on I was glad to find that Mr. John Fritz had come to the same conclusion, and had so reported. I concluded we both could rest content, while awaiting developments. Later still, as we all know, there was another difficulty that Mr. York met with—namely, that the architects or structural engineers would not accept his proposed sections. That is still a great difficulty in America. Later, the Grey mill came into successful operation in Luxemburg, producing such sections, which are being used in England and on the Continent. In fact, the whole process, both from a commercial and a mechanical point of view, is a success. The Bethlehem Steel Co., Bethlehem, Pa.,

Jan 1, 1907

By C. W. Stratford

[During the last few years, the necessity for development work has been generally recognized by executives throughout the oil industry, resulting in greatly accelerated progress and the adoption of many noteworthy improvements in refining methods and equipment. Several years ago, the Associated Oil Co. decided to improve distillation methods with the object of reducing refining costs. This extremely interesting work was entrusted to the writer, and W. S. James, now Chief of Research for Studebaker Corpn. of America, was selected as the principal collaborator. The latter contributed much during his two years with the Associated Oil Co., to the development work that has followed. The writer extends to the Associated Oil Co. his appreciation for permission to disclose the details of distilling equipment. In petroleum refining the principal requisites of good economics are the separation of high-priced distillates from those of lower price; maxi-mum yield of any desired distillate; lowest capital investment in refining equipment; lowest cost of operation and maintenance, and the best adaptability and flexibility of the same refinery equipment for handling crudes of widely varying characteristics. The first two items mentioned, separation and yields of distillates are determined by efficiency of fractionating equipment,. Discussion in this paper is chiefly concerned with oil-heating equipment, combustion and furl economy. It has long been well known that velocity plays a very important part in all heat transfer systems. Any betterment in specific transfer. rates in such systems must. always involve velocity. Realizing this fact, IV decided to adopt as a basic principle, the employment of energy to impart velocity required for high transfer rates through a heating diaphragm, and our method of modernizing obsolete shell stills is founded on this principle. Mechanical energy is usually cheap and its rational rspcntliture is returned in the form of greatly increased heat transfer rates, on both oil and gas sides of the sheet. Certainly there is nothing new in this principle, the only novelty being that of our peculiar method of application On the oil side (Fig. I) use is made of a centrifugal pump to jet the oil against the heated sheet thereby creating a high velocity sheet flow over the entire fired area. Such a pump is one of the most efficient machines, so far developed, for moving fluids. 'I'he oil, under pressure impinging

Jan 1, 1928

The Iron and Steel Committee of the American Institute, of mining and Metallurgical Engineers held a joint session with the American Foundrymen's Association during the Annual Meeting of the Institute in February, 1928, for the purpose of discussing blast-furnace operations and the character of pig iron and castings. Dr. Richard Moldenke presided. H.. H. Sweetser, who was named on the program as the presiding officer of the session, was unable to be present, but sent a letter in which he said: " The meeting we had here last year and the meeting held in Chicago last June showed a desire on the part of blast-furnace men and users of pig iron to get the facts regarding the influence on castings made from pig iron produced in blast furnaces under varying conditions of temperature, mixture and local furnace operations. It has been my hope that at this Round Table we might he able to formulate a series of tests that, would give us the desired information. "Several independent blast-furnace investigations have. been, and still are being, carried on in different sections of the country. The furnaces investigated include a southern furnace, a middle-west furnace, a western furnace and a Chicago district furnace. The results so far show distinct characteristics for each of the four furnaces. It is possible that a furnace in the eastern part of the United States would be different from all the others. "It is hoped that a plan of action can be worked out at your meeting today whereby the IT. S. Bureau of Mines will be able, to carry on more extensive work in connection with the research departments of the different iron and steel companies and the big consumers of pig iron. "No one group can get all of the, information but if the different investigations can be coordinated it will he possible for us to (Iran. conclusions regarding the effects of varying conditions in blast-furnace practice on the pig iron produced and the castings made there from." DISCUSSION R. Moldenke, Watehung, N. J.—I was across the -water this summer and saw some of those interested in an investigation of this kind. 'I'hey told me that in Germany, where they had a joint committee of blast-furnace operators and foundry-

By Ernest Klepetko

A notable amount of fossil resin exists in many of the bituminous coal beds of Utah. The upper part of these show a marked concentration of resin, which occurs primarily in the fracture seams. In general, these seams are less than 1/8 in. thick, but it is not uncommon to find coal with areas as thick as 3/8 inches. The resin is of the hard kauri variety, with coloration varying from deep blood red to lemon yellow and almost colorless. There is also an almost black variety, which is not readily soluble in the same solvents as the lighter colored resins. These resins are valuable for many industrial purposes. When refined, they are suitable for uses similar to those for which lac resins are usually employed. They are particularly desirable for preparing dielectric varnishes. They are also desirable in preparing printing inks, waterproofing agents, special synthetic rubbers and rubber cements. They are especially suitable as an admixture in synthetic rubbers and cements, as they supply the essential tackiness the synthetics lack. The following chemical trade characteristics have been found by Inter-Chemical Co. research chemists in the refined resins: Specific gravity (melted)....... I .03 -I.06 Acid number.................. 6-8 Softening point, mercury method 160º-165ºC Iodine value (Wijs)............ 140-150 Refractive index............... 1.544 Color (Hellige, 25 pct toluol)... 14 Molecular weight, average...... 732 Purity, 99 + pct pure hydrocarbon "Unaffected by alkalies and resistant to one hour fusion with solid potassium hydroxide. Completely soluble in aliphatic and aromatic hydrocarbons. Insoluble in alcohols, ethyl acetate and other commonly used alcohols and esters. Compatible with natural and synthetic rubbers, chlorinated and cyclized rubbers, waxes, vegetable oils, mineral oils, rosin, ester gum, phenolic and modified phenolic resins and other natural and synthetic resins of like solvent solubility."* The recovery and refining of these fossil resins has been the subject of much research work and has intrigued many investigators. Broadly speaking, the problem involves separation of the resin from the coal into a very high-grade concentrate, and subsequent treatment of this concentrate to produce an acceptable refined resin for its various usages. Obviously it is also desirable to recover the residual coal without excessive size degradation. The late W. D. Green, concentration ennineeru for Combined Metals Reduction CO., obtained U, S. Patent No. 1773997 for the recovery of resin from coal through

Jan 1, 1948

By Ernest Klepetko

A notable amount of fossil resin exists in many of the bituminous coal beds of Utah. The upper part of these show a marked concentration of resin, which occurs primarily in the fracture seams. In general, these seams are less than 1/8 in. thick, but it is not uncommon to find coal with areas as thick as 3/8 inches. The resin is of the hard kauri variety, with coloration varying from deep blood red to lemon yellow and almost colorless. There is also an almost black variety, which is not readily soluble in the same solvents as the lighter colored resins. These resins are valuable for many industrial purposes. When refined, they are suitable for uses similar to those for which lac resins are usually employed. They are particularly desirable for preparing dielectric varnishes. They are also desirable in preparing printing inks, waterproofing agents, special synthetic rubbers and rubber cements. They are especially suitable as an admixture in synthetic rubbers and cements, as they supply the essential tackiness the synthetics lack. The following chemical trade characteristics have been found by Inter-Chemical Co. research chemists in the refined resins: Specific gravity (melted)....... I .03 -I.06 Acid number.................. 6-8 Softening point, mercury method 160º-165ºC Iodine value (Wijs)............ 140-150 Refractive index............... 1.544 Color (Hellige, 25 pct toluol)... 14 Molecular weight, average...... 732 Purity, 99 + pct pure hydrocarbon "Unaffected by alkalies and resistant to one hour fusion with solid potassium hydroxide. Completely soluble in aliphatic and aromatic hydrocarbons. Insoluble in alcohols, ethyl acetate and other commonly used alcohols and esters. Compatible with natural and synthetic rubbers, chlorinated and cyclized rubbers, waxes, vegetable oils, mineral oils, rosin, ester gum, phenolic and modified phenolic resins and other natural and synthetic resins of like solvent solubility."* The recovery and refining of these fossil resins has been the subject of much research work and has intrigued many investigators. Broadly speaking, the problem involves separation of the resin from the coal into a very high-grade concentrate, and subsequent treatment of this concentrate to produce an acceptable refined resin for its various usages. Obviously it is also desirable to recover the residual coal without excessive size degradation. The late W. D. Green, concentration ennineeru for Combined Metals Reduction CO., obtained U, S. Patent No. 1773997 for the recovery of resin from coal through

Jan 1, 1948

By AIME

ENGINEERS have long pondered the answer to the question of "How am I doing?" and in large measure the answer from the economics angle is provided by the 1946 survey of the engineering profession now being published by the Engineers Joint Council as an eighty-page bulletin entitled "The Engineering Profession in Transition." The survey, based upon a completely precoded mail questionnaire, aimed at three major objectives: (1) to determine the general impact of World War II upon the profession in the period 1939 through 1946; (2) to obtain re- R liable data from which valid findings could be derived to predict how active the profession would be after 1946; and (3) to determine if the war's upheaval had changed materially the pattern of professional activities, education, background, and earnings from those which existed prior to 1939. Abundant data on the economic status of the engineer based upon years of experience in his particular field, the specific branch of the industry in which he served, and his educational background are presented. Relationships between years of experience

Jan 1, 1947

By David Sinclair

THE dimensions and shapes of mine structures may at present be determined by (1) field experience, (2) structural calculations, and (3) barodynamic tests.§ None of these, however, provide information as to the stresses, their direction and distribution in a mine structure. For the design of pillars, the placing of openings relative to working places such as gangways, haulage levels, etc., this information is desirable. Photoelastic methods provide this and, while relatively new, their appli-cation in all engineering fields is assuming increasing importance. This paper, therefore, will present the method with a few applications to mining, and with sufficient reference for further study by the reader. PART I THE PHOTOELASTIC METHOD The photoelastic method of stress measurement determines the stress distribution in a two-dimensional model by optical means. It makes use of the fact that when a piece of isotropic transparent material, such as glass, celluloid, or Bakelite, is stressed and viewed in polarized** light a picture is seen which indicates by its color bands of light, or fringes, the magnitude of the stresses, their direction and their distribution.

Jan 1, 1940

By C. A. Heiland

IN the third year of war, geophysical oil exploration broke all records to keep pace with the demand for increased reserves. Geophysical prospecting for strategic and other minerals also grew in scope. The trend of geophysical oil exploration throughout the war is indicated in Fig. 1. This figure resembles the one presented in the last annual review issue of M&M (February 1944, p. 62), corrected for data on-operations in the last months of 1943 and extended into 1944. The average number of geophysical oil prospecting crews in the field in 1944 was 451, whereas the total in 1943 was 340. An upward trend in the use of all geophysical methods is clearly evident throughout the year. Seismic operations were 67 per cent, gravimeter surveys 28 per cent, and other methods 5 per cent of the total. Seismic reflection and refraction crews increased 181/2 per cent over the 1943 average, gravimeter operations increased 73 per cent, and other methods gained 92 per cent. The increase in seismic and gravimeter operations, particularly the latter, is probably due to an increased production of equipment and the organization of new service companies. Miscellaneous methods gained largely through a revival of magnetometer work, and an increase in the use of torsion balances and electrical equipment. In comparison with the prewar average of 1941, it is noteworthy that seismic operations increased 58 per cent, gravimeter operations 88 per cent, and miscellaneous other methods gained as much as 283 per cent. Unfortunately the expansion in the number of geophysical crews does not indicate a proportionate increase in efficiency or in areal coverage, as will be brought out later.

Jan 1, 1945