Search Documents

By R. Maddin

IN analyzing the relation between the orientation of new grains and that of the deformed matrix of axially extended and recrystallized single crystals of face-centered cubic metals, a two-stage rotation process" is generally used where the first rotation is made in order to account for an "adjustment of orientation to the environment of strain."&apos; It has been argued that in spite of the difference of orientation, which may amount to as much as 12" (in a brass),&apos; between the octahedral plane as observed in the parent lattice and in the recrystallized grain, it is believed to be a common plane in the sense that it constituted the nucleus in the parent strained crystal from which the new grain grew.&apos; A possible source of the deviation in orientations of a common pole in the new grain and that of the deformed single crystal matrix from which it has grown may be found in the distribution of strain resulting from the plastic deformation. It might be expected in view of the incongruent nature of shear&apos; that the perfection of the octahedral plane along which glide has occurred is disrupted and that this disruption constitutes the strain from which nuclei of new grains can grow during recrystallization. Evidence for the existence of strain along glide planes was first detected by Taylor" in 1927 and substantiated by Collins and Mathewson&apos; in 1940. In their investigations, however, the deformed single crystalline specimens (aluminum) were cut mechanically along the glide planes followed by mechanical polishing. X-ray exposures (glancing angle) of only 8 min with filtered radiation were used. It was later shown&apos; that this type of surface preparation did not remove with all certainty the mechanically disturbed surface. It was felt that a re-investigation of this phenomenon using more refined techniques might reveal a more correct extent of the strain resulting from the deformation which might correlate the deviation of the common pole of the recrystallized grain with the acting slip plane of the matrix crystal. In accordance with these thoughts, a single crystal of a brass (70/30 nominal composition) M in. in diam x 5 in. long, tapered as in previous experiments,&apos; was extended and carefully documented with respect to elongation and shear. Disks about % in. thick paralle&apos;l to the primary slip planes were cut from the specimen by means of an etch cutter." These disks represented volumes of the specimen which had been extended 0, 5, 10, 15, and 20 pct. Copper Ka monochromatic radiation was obtained by reflecting 35,000 v copper radiation from the c-cleavage face of a pentaerythritol crystal. The monochromatic radiation was collimated and led on to the disk set at the proper 0 angle for reflection from the primary (111) planes. The monochromatic beam was aligned in a plane containing the active slip direction. Following a 10 hr exposure at the theoretical Bragg angle, the disk was reset at 0 + 1°, 0 — 1", 0 + 2", 0 — 2", etc., until no Bragg reflection was obtained. The disk was then rotated 90" about its polar axis, and the same X-ray procedure was used. The results are shown in Table I. It may be seen from the results in Table I that the plastic deformation (20 pct elongation) produces fragments of the glide plane which are rotated or tilted as much as 25 " from the normal position on a purely block slip model. In addition to the large variation in 0 angle in the slip direction, there is a variation in 0 as much as 20" in the direction at right angles to the direction of slip, i.e., <110>. In view of the results shown, it may now be argued that the strain distribution finds its origin in the incongruent nature of the slip process.&apos; The use of the two-stage rotation process seems valid in attempting to explain the relation between the orientation of recrystallized grains and the matrix from which they have grown. Acknowledgment This work was sponsored by the ONR under Contract Number N6 onr 234-21 ONR 031-383. The author would like to thank N. K. Chen for reading and correcting the manuscript. References &apos;R. Maddin, C. H. Mathewson, and W. R. Hibbard, Jr.: The Origin of Annealing Twins. Trans. AIME (1949) 185, p. 655; Journal of Metals (September 1949). &apos;J. A. Collins and C. H. Mathewson: Plastic Deformation and Recrystallization of Aluminum Single Crystals. Trans. AIME (1940) 137, p. 150. eN. K. Chen and C. H. Mathewson: Recrystallization of Aluminum Single Crystals After Plastic Extension. Unpublished. 4 C. H. Mathewson: Structural Premises of Strain Hardening and Recrystallization. Trans. A.S.M. (1944) 38. :&apos;C. H. Mathewson: Critical Shear Stress and Incongruent Shear in Plastic Deformation. Trans. Conn. Acad. of Arts and Science, (1951) 38, p. 213. "G. I. Taylor: Resistance to Shear in Metal Crystals, Cohesion and Related Problems. Faraday Soc. (1927) 121. &apos;R. Maddin and W. R. Hibbard, Jr.: Some Observations in the Structure of Alpha Brass After Cutting and Polishing. Trans. AIME (1949) 185, p. 700; Journal of Metals (October 1949). &apos;R. Maddin and W. R. Asher: Apparatus for Cutting Metals Strain-Free. Review of Scientific Instruments (1950) 21, p. 881.

Jan 1, 1953

By M. J. Spendlove, H. W. St. Clair

An automatic surface-follower mechanism was used to measure the surface temperature and the rate of evaporation of molten zinc while undergoing distillation at low pressure. At pressures of 50 to 100 microns Hg, the rate of evaporation may be 60 to 80 pct of the theoretical maximum corresponding to the measured temperature. The rate decreases rapidly at pressures above 100 microns Hg, to only 7 pct of the theoretical maximum at 2000 microns Hg. Measured temperature gradients at the surface are in agreement with theoretical gradients calculated from the heat of vaporization, rate of evaporation, and thermal conductivity of molten zinc. THIS paper covers a series of careful measurements of the rate of evaporation of molten zinc at low pressures, undertaken as a part of a general investigation on the separation of metals by distillation.&apos; Preliminary results on the rate of evaporation of zinc were described in a previous publication.&apos; The results of the preliminary study are as follows: 1—The observed rates of evaporation of zinc were as high as 0.60 g per sq cm per min, corresponding to 75 pct of the maximum rate as determined by the temperature of the metal. 2—The evaporation rate was decreased from 0.30 g per sq cm per min at a pressure of 25 microns to only 0.09 g per sq cm per min when the pressure was increased to 5 mm. 3—The temperature of the surface during rapid evaporation may be 35" to 100°C less than the main mass of metal. Observed temperature gradients at the surface are consistent with those calculated from the heat of vaporization and the thermal conductivity of liquid zinc. In the preliminary experiments, the rate of evaporation was determined from the loss in weight of the metal in the crucible during the test. This was compared with the weight of the condensate. Obviously, this method was subject to error because of some uncertainty as to the period of evaporation that should correspond to the loss in weight. Furthermore, this method did not permit taking into account probable variations in the rate of evaporation during the test. A more serious shortcoming was that the temperature at the evaporating surface was not known, so the maximum theoretical rate of evaporation could not be calculated accurately. To improve the precision of rate measurements and to allow accurate measurements of the surface temperature, a refined experimental technique was developed whereby the temperature and position of the surface could be measured accurately. This was done by an automatic surface-follower mechanism that gave a continuous record of the surface temperature and the amount of zinc evaporated. These data permitted an instantaneous determination of the actual rate of evaporation and the surface temperature throughout the test. Pure zinc (99.99 pct Zn) was used in all experiments. Description of Distillation Furnace The details of construction of the distillation furnace are shown in Fig. l. The furnace is enclosed in a large quartz tube open at one end. The open end of the quartz tube is sealed by means of a water-cooled head. The entire enclosure is vacuum tight. The connection between the water-cooled head and the quartz tube is sealed by means of a rubber gasket which fits tightly against the smooth end of the tube. The metal is heated by induced current set up in the molten zinc and the walls of the graphite crucible by means of a water-cooled induction coil outside the quartz tube. High frequency current is passed through the induction coil from a 6 kw mer-

Jan 1, 1952

By C. A. Pierce

UNDERGROUND operations of the United States Potash Co. at its mine near Carlsbad, N.M., have been continuous since the property was opened about five years ago. Approximately one million tons of potash has been mined and two shafts have been sunk, each to a depth of about 1000 ft. Outstanding in the company&apos;s operations is the fact that not a single blasting accident has occurred during the aforesaid period. The purpose of this paper is to describe the blasting practice that has made possible the achievement of this accident-prevention record. The mining method employed in extracting the thick horizontal bed of potash may be described as a double-entry room-and-pillar system. Mine development is kept well in advance of extraction operations, and a three years&apos; supply of ore, at least, is always available. Limits of the orebody have not been determined, and in the present system of mining headings are advanced by a "shortwall" method. This was the first potash ore bed developed in the United States. The nature of the deposit, therefore, was unknown, and it was deemed expedient to outline a conservative mining policy. Later, when more is known about the deposit and certain control ascertained, a "longwall" panel retreating method may be found advisable. The necessity for a domestic supply of potash became a national issue previous to and during the World War. The United States Govern-ment came to realize that this country should not be dependent upon foreign sources of potash, and began extensive explorations in many parts of the country, seeking an orebody that would meet the exacting require-ments of the domestic market. The Department of Interior, through the Geological Survey and Bureau of Mines, made every effort to determine the location of potash deposits and encouraged their exploitation by private capital. Through the combined efforts of the Department of Interior and private industry, the deposit now being worked by the United States Potash Co. was discovered and brought into production.

Jan 1, 1936

By E. H. Roberts, L. G. Swenson, F. C. Nix, R. A. Morgen

The binary system lead-antimony has been the subject of comprehensive investigations in these laboratories by Dean1 and his associates. The effect of a third constituent on this system, particularly on the lead-rich alloys in which dispersion hardening was found, has a commercial value as well as an academic interest. This paper covers the effect of the addition of copper, bismuth and tin, all of which are likely to be found in commercial lead-antimony alloys, and is divided into three parts, as follows: I. The System Lead-A~ili~r~ony-Copper II. The System Lead-Antimony-Bismuth III. The Lead Corner of the System Lead-Antimony-Ti11 These three systerrls are of three different types, and hence may be considered as covering three general kinds of additions. Bismuth forms no compounds with either lead or antimony and forms solid solutions with both. Copper forms several compounds with antimony as well as solid solutions but with lead it forms a two liquid layer system and no appreciable solid solution. Tin is soluble in both lead and antimony in the solid state and also forms a compound with antimony. The effect of small amounts of bismuth on the lead-antimony alloys is small, having no appreciable effect on the solubility of antimony. The temperature of the solidus floor is lowered appreciably by the presence of bismuth, cutting down the range of heat treatment. Copper, on the other hand, due to compound formation, increases the apparent solubility of antimony. The excess antimony is tied up with the copper finally and so is not available for dispersion hardening. The net result of addition of small amounts of copper is to shift the dispersion hardening peak of the

By W. H. Emmons

Most mineral deposits change as they are followed downward on their dips. Some of these changes are due to primary arrangement; different ores were precipitated at different depths when the deposits were formed. Other changes are due to weathering or secondary enrichment. The chief changes resulting from weathering, in the main, are understood and standard changes are recognized. The processes are relatively simple. They take place at ordinary temperatures and pressures and can be duplicated in the laboratories. Moreover, there are thousands of deposits available for study, because the processes take place near the surface where the development of mines is begun. The changes due to primary arrangement of the deposits of the metals are not so well understood. Deposition has taken place at higher temperatures and our knowledge of the chemistry of the processes leaves much to he desired. Very few experimental data are available. The deposits, moreover, offer fewer examples because many mines are not developed to depths where the changes can be studied and a change to unprofitable material usually results in stopping work. Most students of ore deposits now accept, as confirmed, the hypothesis that nearly all lodes and related deposits were formed by solutions originating in intrusive igneous masses. Outward from these masses, the deposits at many places are grouped in zones and the arrangement noted from the intrusions outward are commonly the reverse of the changes noted from the surface downward in a single lode. A study of the changes in groups of deposits, from the parent intrusion outward, will throw light on the changes to be expected in a single lode downward. Recause the changes in series of deposits from the intrusive outward may all be observed near the surface, where more data are available, it is possible to increase the number of examples many fold and to apply the statisttical method of study with greater confidence of avoiding error. It is not everywhere possible to identify the parent igneous body to which a group of ore deposits are related. Several kinds of criteria are available; certain groups are superior to others. By applying the

Jan 1, 1924

By ELTCENE A. WHITE

WE are all interested in our ou7n lines of endeavor and consider ourselves the center of the universe. The farmer thinks he is the most important man because he feeds us. The doctor knows he is the real center because he keeps us well. The lawyer says that he is indispensable because he keeps the peace. The banker furnishes us a place to keep our money and tells us how to make proper use of it. The miner sags that without metals there would be no civilization. I think that my branch has sufficient interest and exhilaration. of accomplishment to fully occupy any man&apos;s mind and attention. Mining and metallurgy are as old as the human race. It did not have much, if any, importance in the stone age as there are not found remains of iron and copper, but in the bronze age, which was co-existent with the stone age, it came to the front. Iron and copper were the most important metals. Copper, as bronze, was known in ancient Egypt, I\~:IS important in Rome and other parts of Europe and in Asia; in South America among the Aztecs and farther North were the Mound Builders and the early inhabitants of Lake Superior. At a very early date the Egyptians conquered the Sinai peninsula for the sake of the copper produced there. The history of copper metallurgy can be compared to that of a flower. The seed is sown in darkness and in the Dark Ages the crude metallurgy of copper began. As the shoot comes up from the seed it may be compared to the age of alchemy; the branches of the plant can be compared to the Middle Ages; the flowering shoots to the 17th century, the budding to the 19th and the blossom to our own time from 1870 on.

Jan 1, 1930

By AIME AIME

THE 1944 Chairman of the Institute of Metals Division might be classed as metallurgically ambidextrous ; he is teacher of theory and practice of both nonferrous and ferrous metallurgy, and he is consultant on brass and on highspred steel. Arthur Phillips was born in Troy N.Y. and attended the New Haven Connecticut high school. Upon graduation he entered Yale, receiving a degree in metallurgy in 1913. At that time Professor Mathewson was starting his plan of &apos;"co-operation with the metal industries in metallographic work at the Hammond Laboratory of the Sheffield Scientific School, Yale University, and Arthur Phillip, became the first co-operative graduate student, working in the laboratory of the Bridgeport Brass Co., and receiving his Masters of Science degree in 1915. A little later, when the department of metallurgy at Yale was expanded. Me. Phillips was appointed assistant professor. In 1928 he was made associate professor, and in 1934 he was promoted to full professor.

Jan 1, 1944

By Howard L. Hartman, Burke O. Trafton

There is a fruitful area of computer competence which has gone virtually unnoticed by the mining industry. This is in the solution of its numerous fluid-flow distribution problems, involving the circulation of air, water and other fluids in conduits through mines. Typical of these is the mine ventilation system, which circulates air through mine openings to the working faces. The networks of interconnected airways in large mines-often resembling a tortuous maze or labyrinth defying representation by schematic, let alone solution-must somehow be resolved and analyzed, if effective and safe control of the ventilation is to be maintained. These are admirably suited to programming for solution by high-speed electronic computer. Not only can direction of flow be determined but quantity and head loss as well. EARLIER EFFORTS AT NETWORK SOLUTION The only prior attempt to solve mine ventilation networks by digital computer methods was made by a Japanese investigator1 in 1958 whose work went unpublished. Unfortunately, he employed a method of network analysis little used in the United States and one which could accommodate a maximum of only 30 airways. While his analysis seems unnecessarily cumbersome and involved, it did suggest that a digital computer approach was feasible.

Jan 9, 1963

By V. Rajaram

The oil shales of the Green River Formation in the United States have been considered as a source of liquid hydrocarbons since 1908, with the first retort constructed in Colorado in 1917. However, it was not until 1944 that the mining characteristics of oil shale were investigated in a systematic manner. During the period 1944 through 1956, the Selective Mine and the Demonstration Mine (also referred to as the Anvil Points Mine) were operated by the U. S. Bureau of Mines (USBM) near Rifle, Colorado. Significant progress was made in developing a room and pillar mining method by which oil shale could be mined safely at a very low cost per ton. Mechanical properties of oil shale were determined, safe room spans and roof support techniques were established, and drilling and blasting methods for oil shale were developed. As a follow-on to this USBM effort, a consortium of six oil companies with Mobil Oil Company as project manager carried out a research program during the period 1964-68 at the Mobil mine, located in the vicinity of the Anvil Points mine. Rock mechanics investigations were conducted as a part of this research program, and consisted of laboratory studies, in-situ stress determinations, and roof and pillar instrumentation. This paper will discuss the findings at the Anvil Points mine and Mobil mine to illustrate the stability considerations in underground oil shale mining.

Jan 1, 1983

By M. D. Cooper

UNDERGRADUATES in mining engineering may be prepared for work by giving them sound instruction in the courses generally considered essential to the profession. The industry is not deeply concerned about the details of those courses. The average man in the coal industry does not wish to insist upon a rigid program. Therefore, he differs little from those in the teaching profession-who evidently are not unanimous in their opinions, or all college catalogs would be alike. For the good of the profession, it is just as well that there should be differences in regard to details. It appears that students graduating in mining engineering from the accredited institutions receive similar instruction.

Jan 1, 1950

United Engineering Society ARTHUR S DWIGHT J VIPOND DAVIES J V N Dorm Engineering Societies Library Board SIDNEY H BALL ALEXANDER C HUMPHRFYS GEORGE C STONE JOHN H JANEWAY Engineering Foundation Board H M BOYLSTON J VIPOND DAVIES GALEN H CLEVENGER Society for Promotion of Engineering Education WILLIAM KELLY ALLEN H ROGERS

Jan 1, 1923

[United Engineering Society ARTHUR S. DWIGHT J, VIPOND DAVIES J, V, N. DORR Engineering Societies Library Board SYDNEY H. BALL ALEXANDER C, HUMPHREYS GEORGE C, STONE JOHN H, JANEWAY Engineering Foundation Board H. M. BOYLSTON J. VIPOND DAVIES GALEN H, CLEVENGER Society for Promotion of Engineering Education WILLIAM KELLY ALLEN H. ROGERS]

Jan 1, 1928

By William H. Spice

The area on which oil and gas development is reported covers 30 counties, which are included in the Texas Railroad Commission&apos;s District No. I. This area not only includes the old established Balcones fault-line group of producing fields but also includes the southwest extension of this trend and some of the deeper Wilcox (Eocene) exploratory development. (Fig. J.) In the old Balcones fault-line zone, three new fields were discovered during 1941. These fields are comparatively small, producing from Dale limestone or Austin chalk. No new fields were discovered during the year in the Edwards (Lower Cretaceous) limestone horizon. One new shallow field was discovered in the Reklaw (Eocene) sand horizon and, in the southwestern part of the district, one oil field and one gas field were discovered in the Navarro (Upper Cretaceous) sand horizon. An extremely important extension was made to the one producing Wilcox (Eocene) field of the district in the Washburn Ranch field of La Salle County. The district produced 6,650,357 bbl. during 1941, which was a 12 per cent decrease under production for 1940. Approximately 4,954,000 bbl. of this total production was produced by the three Edwards limestone fields, Luling, Salt Flat and Darst Creek, the remaining production coming from the other 43 active fields in the district. In all, 3694 wells were producing at the end of 1941, compared with 3559 wells at the end of the previous year. During the year, 139 new producing wells were completed and 29 wells were abandoned in the producing fields. The increase in producing wells represents an increase in new wells over abandonments in these fields, together with a decrease in wells temporarily shut down as of the end of 1941. The majority of production drilling was carried on in the following fields; Bee Creek, Chicon Lake, Elm Creek, Gas Ridge, Pearsall and Tenney Creek. Approximately 250 wells were drilled during 1941, of which 110 were exploratory wells completed as failures throughout the district. Considerable exploratory work was continued during 1941 along the Wilcox trend. Geophysical work employing various types of geophysical methods and leasing activity was continued along this trend, particularly by the major companies. The significance of this activity is apparent from the successful extension and development in the Washburn field of La Salle County, where several well-developed gas-and-oil producing horizons have been developed in the lower Wilcox section between 5100 and 5600 ft. as noted in the following paragraphs. Continued exploratory activity along this general trend as far as present conditions will permit is predicted for 1942. New Fields Elgin Field, Bastrop County.—No. I-A Hiram Walker, Marts and Beaven, Inc., discovery well of the Elgin field, was com pleted on Apr. 22, 1941, in broken Austin chalk from 2820 to 2840 ft., pumping 105 bbl. per day, 36.8°A.P.I. gravity. The well apparently is producing from a crevice in

Jan 1, 1942

By William H. Spice

The area on which oil and gas development is reported covers 30 counties, which are included in the Texas Railroad Commission&apos;s District No. I. This area not only includes the old established Balcones fault-line group of producing fields but also includes the southwest extension of this trend and some of the deeper Wilcox (Eocene) exploratory development. (Fig. J.) In the old Balcones fault-line zone, three new fields were discovered during 1941. These fields are comparatively small, producing from Dale limestone or Austin chalk. No new fields were discovered during the year in the Edwards (Lower Cretaceous) limestone horizon. One new shallow field was discovered in the Reklaw (Eocene) sand horizon and, in the southwestern part of the district, one oil field and one gas field were discovered in the Navarro (Upper Cretaceous) sand horizon. An extremely important extension was made to the one producing Wilcox (Eocene) field of the district in the Washburn Ranch field of La Salle County. The district produced 6,650,357 bbl. during 1941, which was a 12 per cent decrease under production for 1940. Approximately 4,954,000 bbl. of this total production was produced by the three Edwards limestone fields, Luling, Salt Flat and Darst Creek, the remaining production coming from the other 43 active fields in the district. In all, 3694 wells were producing at the end of 1941, compared with 3559 wells at the end of the previous year. During the year, 139 new producing wells were completed and 29 wells were abandoned in the producing fields. The increase in producing wells represents an increase in new wells over abandonments in these fields, together with a decrease in wells temporarily shut down as of the end of 1941. The majority of production drilling was carried on in the following fields; Bee Creek, Chicon Lake, Elm Creek, Gas Ridge, Pearsall and Tenney Creek. Approximately 250 wells were drilled during 1941, of which 110 were exploratory wells completed as failures throughout the district. Considerable exploratory work was continued during 1941 along the Wilcox trend. Geophysical work employing various types of geophysical methods and leasing activity was continued along this trend, particularly by the major companies. The significance of this activity is apparent from the successful extension and development in the Washburn field of La Salle County, where several well-developed gas-and-oil producing horizons have been developed in the lower Wilcox section between 5100 and 5600 ft. as noted in the following paragraphs. Continued exploratory activity along this general trend as far as present conditions will permit is predicted for 1942. New Fields Elgin Field, Bastrop County.—No. I-A Hiram Walker, Marts and Beaven, Inc., discovery well of the Elgin field, was com pleted on Apr. 22, 1941, in broken Austin chalk from 2820 to 2840 ft., pumping 105 bbl. per day, 36.8°A.P.I. gravity. The well apparently is producing from a crevice in

Jan 1, 1942

By F. H. Gilpin

SINCE Noah pitched his ark within and without with pitch, the use of asphalt in human endeavor has been increasing-for Noah&apos;s pitch was asphalt. Asphalt is a bituminous material found in nature, either pure or admixed with smaller or greater quanti-ties of mineral and non-mineral materials, or obtained by the refining of crude asphaltic-base petroleum under proper methods of control. Native or "natural" asphalts are scattered through-out the world, though the commercial value of the various deposits varies greatly, depending upon both their accessibility and magnitude and the quality of the material found. It is an acknowledged fact that such asphalts have been produced through natural causes by practically the same application of tempera-ture and pressure as are used in the modern refining of crude asphaltic-base petroleum. The best known of all the native asphalt deposits are those of Trinidad Lake in the Island of Trinidad, British West Indies, and of Bermudez Lake in Vene-zuela. Asphalt from Trinidad Lake, after refining to remove organic and some inorganic diluents, contains approximately 35 per cent, of inorganic residue, and the asphalt thus produced must be fluxed with lighter asphaltic or semi-asphaltic base oil to make it com-mercially utilizable. The refined asphalt obtained from the Bermudez Lake deposit contains from 4 to 6 per cent. of inorganic material which cannot be removed. This asphalt, also, must be fluxed to produce com-mercial products. Small quantities of similar materials are available in other locations. The best pure native asphalt&apos; is known as. gilsonite and is mined in com-mercial quantities in the State of Utah. In numerous places in the United States, particularly Oklahoma and Kentucky, there are deposits of sand¬stone and limestone impregnated with bitumen, which are known as rock asphalts. These rock asphalts may be used, particularly in the paving industry, either as found or by slight fluxing; from some deposits the asphalt is extracted and marketed commercially.

Jan 2, 1923

CONTENTS PAGE PEIRCE, CARL-Making Rimmed Steel. Discussed by L. F. Reinartz. H. D. Hibbard, C. L. Kinney, Jr., A. H. Woodward, V. B. Buck, A. L. Feild, J. V. W. Reynders 1 SCHROEDER, F. W., and LARSEN, B. M.-Progress Report of the Effect of the Open-hearth Process on Refractories. Discussed by D. A. Lyon 12 KEATS, J. L., and HERTY, C. H.-Elimination of Metalloids in the Basic Open-hearth Process. Discussed by J. V. W. Reynders 14 Making Rimmed Steel Discussion of paper by CARL PEIRCE, presented at the New York fleeting and issued, as Paper No. 1563-C, with MINING AND METALLURGY, March, 1926. L. F. REINARTZ, Middletown, Ohio.-Mr. Carl Peirce has presented a valuable paper on a subject that has been very widely discussed in recent years, especially since the demand for high finish, deep drawing and other grades of sheet steel in the lower carbon ranges has become an important factor in the steel business. Steel of this analysis has been produced for many years, but the product for which it was made did not require the extra care in the steel plant that it does today. It must now be worked down into thin sheets for special purposes and undergo many severe finishing processes both in the steel mill and in the fabricating plants. Mr. Peirce&apos;s paper has outlined in a concise and logical manner the steps which must be taken in manufacturing such steels. The secret of successs is attention to details of well known steel practices. I agree with him that quality steels of this class cannot normally be made out of inferior raw materials. Scrap should be clean and if possible not too variable in analysis. Galvanized scrap or babbit are particularly objectionable. Scrap should be in such physical condition that undue delays are not encountered in charging the furnace. Limestone should preferably contain over 95 per cent. available calcium carbonate, and be free from clay or other foreign substances. Almost universal practice shows that 10 per cent. limestone is required for proper slag volumes to protect the metal from over oxidation. The use of 8 per cent. limestone makes the operation less fool-proof.

Jan 4, 1926

By H. W. Camp

ALTHOUGH the situation in the oil industry during the past year has. not been conducive to large expenditures for development and research, there is little indication that such expenditures have been curtailed. While few outstanding achievements have been reported, considerable progress has been made in the development of new products and the adaptation of petroleum derivatives to new uses. The most important question facing the refiner today is the anti-knock quality of his gasoline. This year has seen the widespread adoption of the term "octane number" as a measure for anti-knock values, and in the latter months of the year the public has been made acutely aware of this condition through competitive advertising. Gaso-line is no longer priced on volatility and gravity alone, but on octane number as well; and premiums are being paid for material of relatively high octane rating. The situation has grown more and more competitive and has forced refiners continually to raise the octane rating of their regular and com-petitive grades, and at this writing the same situation exists for premium grades which have possessed relatively high anti-knock properties for some time. Straight-run gasoline produced from paraffin-base or semiparaffin-base crudes has an inherently low anti-knock value, and in order to convert this material to a higher quality it has been found necessary to crack an increasing percentage of the crude oil charge. By completely cracking the heavier portions of the crude, and blending back with the straight-run gasoline, it has been possible to produce an average of 63 to 65 octane number gasoline&apos; on average Mid-Continent crude. This operation carried to the fullest extent does not suffice, however, and the recent and rapid development of the so-called "re-forming unit," has resulted. The straight-run gasoline fraction is cut into two parts: a light, low boiling point gasoline; and a heavy gasoline or naphtha. The latter containing the low anti-knock portions of the gasoline, is sent through a re-forming unit and subjected either to high temperature ,or pressure, or both, which materially increases its octane number. On average Mid-Continent the blend of low boiling point straight-run,

Jan 1, 1932

ROBERT VAN ARSDALE NORRIS, who died at his home at Wilkes-Barre, Pa., on April 20, 1928, was born at Newark, N. J., on May 2, 1864, of parents who were direct descendants of such sterling New Eng-landers as Governor William Bradford, John Alden and Timothy Dwight. He went to the Collegiate School in New York and then to the Colum-bia School of Mines where he graduated with the class of 1885, having among class-mates A. S. Dwight, E. N. En-gelhardt, H. L. Hollis, G. B. Lee, Richard Moldenke, Wil-bur Sanders, Joseph Struth-ers, E. A. Wiltsee, and I. H. Woolson. His marked ability even among so many men of unusual ability caused him to be chosen as assistant to Pro- fessor Munroe in the summer school of mining and survey-ing immediately after gradua-tion, and he shortly after was also inspector of dredging operations on the Maurice River improvement work, Millville, N. J. The follow- ing year he worked in the chemical laboratory of Herman Behr in Brooklyn, and toward the end of 1886 he joined the staff of the Pennsylvania R. R. Coal Co. and the Susquehanna Coal Co. as assistant engineer. Six years later he was made principal assistant en- gineer and in 1900 he was made chief engineer of these companies. In 1904, he withdrew from them and estab- lished an office as a consulting engineer at Wilkes- Barre, later taking his son, Robert V., Jr., into partner- ship with him. They acted as consulting engineers for the coal department of the Delaware, Lackawanna & Western R. R. Co., the Lehigh Valley Coal Co., Coke Bros. & Go., Inc., the coal department of the Pennsyl- vania R. R. Co., the Wilkes-Barre & Hazelton R. R. Co., the Sterling Salt Co., and others, specializing in ex- amination and appraisal of coal properties, and also matters of Federal taxation.

Jan 5, 1928

By H. F. Moore

We have studied the simple case of repeated stress, without considering impact, which might bring in other factors. This investigation has shown that steel under repeated applications of stress, reversed from positive to negative, will not fail below some fairly clearly defined limiting stress that, so far we can see, does not bear any definite relation to the ordinary elastic limit, being as large as the elastic limit in some cases and about one-half the elastic limit in others. According to one theory, fatigue is the result of changes in crystalline structure by repeated stress. I do not know of any evidence in favor of this theory. The crystals are broken under repeated stress. According to Bauschinger, under repeated stress some inherent property of the material changes its elastic limit; possibly some property of the amorphous cement between the crystals. A third theory is that all fatigue of metals is the result of the spread of damage from little localized overstresses. While I do not feel justified in accepting the last theory rather than the second, I have yet to run across a case of failure of steel or other metal, either in the laboratory or in service, that could not be explained by the gradual spread of damage from some nucleus. We have found, for example, that it is possible to subject a homogeneous steel, like Armco iron or a 0.90 per cent. carbon steel, that has been thoroughly annealed, to one hundred million reversals of stress as high as the elastic limit of the steel with no sign of failure. On the other hand, a complex structured steel, like a chrome-nickel steel that has been hardened with very little drawing, will fail at a stress about 58 per cent. of its elastic limit. Between these two we get a variety of results. In the steel work of any building, there are undoubtedly many thousands of places where structural damage was done—where riveted members were bent into place cold and where the rivets were fitted with drift pins, etc. Locally the steel in the building was stressed beyond its yield point in many places. These little localized overstresses do no damage at all; the building is entirely safe. But if this building were subjected eight or ten times a day to a mild earthquake, these little localized overstresses might be nuclei from which damage would spread

Jan 1, 1922

Executive JVW REYNOLDS, Chairman SYDNEY H BALL E DEGOLYER WILLIAM H BASSETT SAMUEL A TAYLOR Finance GEORGE D BARRON, Chairman H A GUESS GEORGE OTIS SMITH Membership ] H CALLOW, Chairman GEORGE D BARRON WILBER JUDSON JOHN A CHURCH, JR H N SPICER Alternates LEWIS W FRANCIS LOUIS D HUNTOON F T RUBIDGE

Jan 1, 1923