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By J. F. Evers, S. Sadiq, F. W. Preston, G. W. Swift

Proper scaling of unsteady-state flow in laboratory gas reservoir models can be achieved if the permeability/fractional porosity ratio is less than 0.5 md. Porous media meeting this specification can be obtained from mixtures of sand and Portland cement provided (1) the water/cement ratio is in the range of 0.35 to 0.40, (2) the sand/cement ratio is in the range of 1/1 to 2/1, (3) the sand grain size is in the range of 48-100 to 18-28 mesh, (4) the mortar curing time is 7 days or more and (5) the cured mortar is dried under vacuum to reduce the temperature level employed during the drying process. The areal homogeneity of the mortars tested is reasonably good, although significant trends in vertical permeability were noted. The Klinkenberg and non-Darcy coefficients of mortar are such that proper scaling of these effects in the laboratory model could be expected. INTRODUCTION A long term deliverability prediction for a gas well is generally based on data determined from flow tests that are of short duration relative to the producing life of the well. These data, together with an estimate of gas reserves in place, form the basis for establishing the parameters of the mathematical model used to predict performance at future times. Results obtained from a mathematical model represent only an interpretation of the physical process being modeled. Experimental verification of the production process from discovery to abandonment is needed where production occurs under carefully controlled conditions. Ideally, one might consider such an experiment to be conducted in the field. Even if the cost of such an experiment could be justified, the time required would make it impractical to consider. However, if the time scaling problem could be handled properly, an experimental model of the gas reservoir production process could provide the necessary data to study the mechanisms of the production process in a reasonable time period. An experimental model has been designed and constructed using the data of this study as a basis. The model reservoir system consists of one producing well located at the center of a right-circular cylinder of porous material. Ten to 15 observation wells are located at strategic offset positions from the producing well. These wells, and the producing well, are fitted with pressure transducers so that the pressure-time history can be recorded at various radial and azimuthal positions in the drainage area during the entire production life of the system. Time is scaled in the model so that the time required to produce gas from discovery pressure to abandonment pressure is about 2 hours. This compares with a 20-year producing life in the model's field counterpart and gives a time scale factor of approximately 1:100,000. DESIGN CRITERIA To establish design criteria for the experimental model, the reservoir is considered to be a finite right-circular cylinder of radius rr, and height h with a producing well of radius rw located at the center and completed through the producing formation. This reservoir consists of a porous medium which has a uniform permeability k and gas porosity and the gas contained in the reservoir has density p, viscosity µ and molecular weight M. Initially, the pressure at all points within the reservoir is uniform at po. and the reservoir temperature is T. Since the reservoir production process has been demonstrated to occur in two distinct transient modes for either Darcy or non-Darcy flow,l it is

By G. Y. Chin, A. R. Von Neida

The relationship between crystalline texture and magnetic anisotropy in a Co-10 pct Fe alloy has been investigated by means of X-ray pole .figures, hysteresis-loop tracings, and magnetic-torque measurements. The cold-rolled texture of a sample after 95 pct thickness reduction is of the "brass-type", that is, (110)[112/. At 500°C the cold-rolled material recrystallizes fo a (311)[112] orientation, plus a minor (210) [001] component. This texture persists up to 1400°C, at which point it is replaced by a secondary recrystallization texture, (111)[112]. Magnetic-torque measurements show that the easy axis of magnetization lies along the transverse direction in the cold-rolled material and changes to the rolling direction after primary recrystallization. This change is also reflected in the hysteresis characteristic; whereas the B-H loop along the rolling direction is nonsqunre with a low value of residual induction (750 vs 19,000 gauss at saturation) for the cold-rolled material, the annealed sample exhibits a very square loop with a large value of residual induction (16,000 gauss). Theoretical torque curves calculated from the texture data on the basis of magnetocystalline anisotropy energy compare favorably with the observed torque curves. Values of the crystal anisotropy constant, K1, obbained from these comparisons are in good quantitative agreement with single-crystal data. Furthermore, both the torque amplitude of the poly crystalline material and the magnitude of K1 obtained with a single crystal show an identical temperature dependence over the range from —195° 10 +220°C. It is thus conclzided that the magnetocrystalline anisotrpopy erlergy is chiefly I-esponsible. for the nzagnetic allisotropy of textured Co-10 pct Fe alloy. THE results of a study on the relationship between crystalline texture and magnetic anisotropy of an alloy containing 90 pct Co and 10 pct Fe by weight are reported in this paper. The alloy has an fcc structure: a saturation magnetization of about 19,000 gauss,2 and a nearly zero value of magnetoatriction.3 puzey4 has reported a large crystalline anisotropy constant of -7.4 X 105 ergs per cu cm, indicating the (111) directions as the easy axes of magnetization. Hence, texture variations resulting from cold work and annealing are expected to introduce a magnetic anisotropy in the polycrystalline material through the alignment of these (111) easy directions. In the present study, magnetic anisotropy of both rolled and annealed strips was determined by magnetic-torque measurements and hysteresis-loop tracings The results were correlated quantitatively with calculations based on texture data obtained by the X-ray pole-figure technique. It is established that the magnetocrystalline anisotropy energy is indeed chiefly responsible for the magnetic anisotropy of textured Co-10 pct Fe alloy. EXPERIMENTAL Material Preparation. The alloy nominally contained 90 pct Co, 9.5 pct Fe, and 0.5 pct Mn by weight, the chief impurities being nickel, carbon, and silicon (less than 0.5 pct total). The cast ingot was rolled to strips 10 mils thick and slit to 1 in. in width. After strand annealing at 900°C in a hydrogen atmosphere, these strips were further cold-rolled to various thicknesses down to 0.25 mil (97.5 pct reduction), with samples collected for study of the development of texture and magnetic anisotropy as a function of thickness reduction. subsequently, samples cold-rolled from 100 mils to 0.25 mil were obtained, thus extending the thickness reduction range to 99.75 pct. In addition, 0.5-mil samples cold-rolled from 10 mils were selected

Jan 1, 1965

By John Jermain Porter

In taking up this subject it is first necessary to define our terms. Efficiency, in its engineering usage, means the ratio between actual and theoretical results, and efficiency-records thus involve the use of scientifically determined standards with which all results are compared. Scientific management is the methods used in increasing efficiency, and includes the use of efficiency-records. Efficiencj-records do not alone constitute scientific management, but they are necessary to it, and any so-called system of management which is not based upon standards and standardization is fundamentally wrong. An efficient management and efficiency-methods in management are not the same thing. There are some people who have an instinctive genius for management and accomplish results without exactly knowing how they do it. Such a manager may obtain a very high efficiency without the aid of scientifically determined standards. On the other hand, it sometimes happens that poor results will accompany the use of efficiency-recorcis, due to a weak or indifferent management, which fails to make use of the information acquired. Efficiency-records are only a tool, and like other tools are worthless unless used. The ordinary cost-sheet and production-statement do not go far enough. They tell what has been done, but give no information as to how well it has been done. It is true that the man who is familiar with the industry and the plant in question may draw inferences and form a general idea of good work or bad work, but it can only be a very general and hazy idea. Comparisons with previous records or records of other plants are unsatisfactory, since there is nothing to show the cause of the differences. Efficiency-records supply this need. They compare actual

Jan 1, 1913

The following is a partial list of members and guests who called at Institute headquarters during the period Sept. 10, 1917, to Oct. 10,1917. Thomas J. Adams, Rahway, N. J. Leon Root Long, Tirapata, Peru, So. Am. L. W. Bahney, Waterbury, Conn. F. M. McClenahan, Ben Avon, Pa. D. W. Brunton, Denver, Colo. E. Francis McCrossin, Birmingham, Ala. J. R. Buchanan, Pasadena, Cal. P. S. Moses, Savannah, Ga. R. C. Canby, Wallingford, Conn. William A. Nelson, Cartersville, Ga. Paul R. Cook, Zaruma, Ecuador. Edmund Newton, Minneapolis, Minn. F. Crabtree, Pittsburgh, Pa. Askin M. Nicholas, Porrington, N. S. W., J. T. K. Crossfield, Chuquicamata Chile. Australia. Wayne Darlington, Georgetown, S. C. E. G. Norton, Chicago, Ill. R. W. Deacon, Elizabeth, N. J. M. L. O'Neale, Coal City, .Ala. Alexander Deussen, Houston, Tex. W. E. Pomeroy, El Paso, Tex. G. G. Dobbs, Bessemer, Ala. Joseph P. Ruth, Denver, Colo. E. B. Durham, Canonsburg, Pa. Gustavus Sessinghaus, Denver, Colo. L. H. Duschak, Berkeley, Cal. A. L. Sweetser, Boston, Mass. F. A. Fahrenwald, Cleveland O. G. M. Taylor, Colorado Springs, Colo. A. H. Fay, Washington, D. a. Allan G. Waite, Dragoon, Ariz. C. L. French, Brooklyn, N. Y. H. Vincent Wallace, Los Angeles, Cal. Carlos F. Galan, Riverside, Mex. H. A. Wentworth, Boston, Mass. Herman Garlichs, St. Louis, Mo. Alfred W. G. Wilson, Ottawa, Canada. Ernest Klepetko, Anaconda, Mont. Samuel S. Wyer, Columbus, O. D. A. Lyon, Washington, D. C. M. M. Albertson has accepted a position with the McIntyre-Porcupine Gold Mines, Ltd., Schumacher, Out., Canada. James A. Block is now employed by the Ray Consolidated Copper Co., of Hayden, Ariz.

Jan 11, 1917

By G. C. Wallick, W. R. Foster, J. G. Savins

A comprehensive review of the salient features of the differentiation method of rheological analysis in Poiseuille flow from its inception circa 1928 is presented. Here no initial assumptions regarding the nature of the function relating rheological parameters to observed kinematical and dynamical parameters are required in the data-analysis process. In contrast, the integration method involves interpreting flow properties in terms of a particular ideal model. It is shown that, although both methods represent modes of solution of the same integral equation, being relatively bias-free, the differentiation method offers a more discriminating procedure for rheological analysis. The application to problems involving plane Poiseuille flow is also described. INTRODUCTION In most instances, the approach to the problem of interpreting the rheological properties of various compositions as they are affected by changes in chemical or physical environment, assaying the characteristics of a particular constituent of a suspension, analyzing flow behavior in terms of interactions between components in a system, to cite but a few examples, has been in terms of what Hersey1 terms the integration method. Briefly, it consists of interpreting flow properties in terms of a particular ideal model. The usual practice of the integration method is to choose a model with a minimum number of parameters because, other things being equal, it is desirable to use the simplest model which will describe the behavior of a real material and yet be mathematically tractable for the requirements of data analysis. This expression is then substituted into an equation which relates observed kinematical and dynamical quantities, such as volume flux Q and pressure gradient ], and angular velocity and torque T, in a capillary and concentric cylinder apparatus, respectively. The rheological parameters appear on integrating, in an expression relating the pairs of observable quantities such as those just given. In many instances a particular model provides a good representation of rheological behavior over a reasonable range of compositional and environmental changes. Just as often, however, it is obvious that the interpretation of rheological changes by the integration method is not providing realistic information about changes in flow behavior. A more general method of interpreting rheological data for a given material is to make no initial assumptions regarding the nature of the function relating rheological parameters to observed kinematical and dynamical quantities, e.g., flow rate and pressure drop in capillary flow or angular velocity and torque in a rotational viscometer. This general method Hersey1 terms the differentia-ation method. Instead of integrating, one differentiates the integral equation with respect to one of the limits, i.e., one of the boundary conditions; the resulting expression contains the same observable quantities just given, their derivatives, and the rheological function evaluated at that boundary. By obtaining these derivatives from experimental data, graphically or by a computer routine, they can be substituted into the differential equation and a graphical form of the function derived. THEORY OF THE DIFFERENTIATION METHOD FOR POISEUILLE-TYPE FLOWS In this introductory paper, two flow cases which are important in viscometry are considered (one for the first time) from the differentiation method of analysis, flow in a cylindrical tube and flow between fixed parallel surfaces of infinite extent, the basic integral equations being formulated in a manner analogous to the way they originally appeared in the literature. In addition, the following ideal conditions will be assumed: (1) an absence of anomalous wall effects, (2) isotropic behavior everywhere, and (3) steady laminar flow conditions. Before proceeding it would seem appropriate to preface the analysis of these flow geometries with the comment that the basic philosophy of the differentiation method could be said to stem directly from the efforts of Herzog and weissenberg2 to indicate systematically the various ways of using

NORTH AMERICA ALASKA Anchorage.-Neitzert, G. H. Strandberg, H. Candle.-Robbins, J. S. College.-Barber, R. J. Burns, W. T. Coats, R. R. Fox. E. F. Joesting, H. R. McAnerney, J. M. Colorado Station.-Beyer, A. Stanford, J. V. Douglas.-Cahill, W. E. Carlson, L. Fairbanks.-Crawford, J. D. Earling, R. B. Fowler, D. A. Greves, J. H. Henton, H. M. Herbert, C. F. Hopkins, J. E. Kreitlow, E. J. MacDonald, D., III Mathews, T. C. McCarty, W. J. McNair, W. H. Metcalfe, J. B. Mikami, H. M. Mize, R. J. CANADA ALBERTA Calgary.-Johnson, R. V. Link, T. A. Marple, L. E. Slipper, S. E. Thorne, B. L. Thorne, H. L. Vissac. G. A. Edmonton.-Ball, -M. W. Lilge, E. O. Pitcher, N. C. Nordegg.-Shanks, J. BRITISH COLUMBIA Allenby.-Lindsay, W. R. Bralorne.-Almstrom, A. A. Bosustow, R. Currie, J. M. Gibson, S. Schmitt, D. E. G. Wilson, G. H. Bridge River.¬Botterill, T. C. Crane, G. A.

Jan 1, 1939

Albin, B. R Billings, Mont. '28 Amster, Nathan L . , 25 Broad St, New York, N. Y. '28 Bache, Jules S 42 Broadway, New York, N. Y. '28 Barrett, C. P 5338 Harper Ave, Chicago, Ill. '28 Baum, Frank G Hobart Bldg., San Francisco, Cal. '28 Bayless, Ron. William S Russ Bldg , San Francisco, Cal. ' 28 Bean, Louts H., V.P., Dwight P. Robinson & Co, Inc 125 E. 46th St, New York, N Y. '23 Beatty, Ross J 1105 First National Bank Bldg., Chicago, Ill. '28 Benwell, Oswald F 205 Colorado National Bank, Denver, Colo. '28 Beymer, Albert S., V.P., Keystone National Bank Pittsburgh, Pa. '28 Bingham, Charles W 1542 Hanna Bldg, Cleveland, Ohio. '28 Blumenthal, Hugo 44 Pine St, New York, N. Y. '28 Boettcher, Charles Ideal Cement Bldg., Denver, Colo. '28 Bowlus, Thomas H Iola, Kans. '28 Bragg, E. B Carmel, Cal. '28 Brown, Colvin B Chamber of Commerce, Washington, D. C. '28 Burt, Maxwell Struthers Southern Pines, N. C. '28

Jan 1, 1923

By Warden A. Moller

The Fushun coal-field, now being opened up by the South Manchurian Railway Co., is connected with the main line by a branch, 30 miles long, from Sui Chia Tun, 10 miles south of hlukden, the oapital of Manchuria. The coal-field, which lies on the southern bank of the Hun river, 25 miles east of Xiukden, consists of a long narrow valley, running east and west between hills composed of granitic and volcanic rocks. At the foot of the northern hills, the Hun river flows westward towards the Liao river, which drains the greater part of South Manchuria. At the foot of the southern hills, resting immediately upon volcanic rocks, and overlain by 30 ft. of alluvium, is a thick layer of Tertiary shales, carrying near the base two coal-seams. In many places the lower of these two seams is in immediate contact with volcanic lavas and basalts, the flows of which were evidently both prior and subsequent to the formation of the coal-seams. This contact has practically destroyed the lower seam for commercial purposes. The value of the field lies in the upper seam, which, for a length of nearly 8 miles, varies from 100 to 130 ft. thick. Of this seam, 85 per cent. is good coal. The seam dips to the north conformably with the shales, at angles of from 25 to 30°, and appears to have an uninterrupted dip for about 1.5 miles before being possibly cut oft' by the northern hills. The coal-bearing shales extend east and west for a length of about SO miles, but towards the east the continuity of the seams is broken by intrusive rocks. The coal is of the sub-bituminous variety, low in ash, bright in appearance, and breaks with a conchoidal fracture. It has the usual qualities of Tertiary coal—quick steam-raising and poor stacking qualities. Pieces of resin, varging in size from

Jan 1, 1911

E. A. Loria (Product Metallurgical Engineer, Crucible Steel Co. of America, Pittsburgh)—In this interesting paper, our introductory work was quoted. We would like to call attention to our sequel paper on the experimental determination of oxygen in cupola-melted cast iron,20 which was not mentioned. Vacuum-fusion oxygen values (as well as hydrogen and nitrogen) were reported for nine heats of cast iron melted in the Battelle 10-in. cupola under normal operating practice and under oxidizing conditions. The oxygen analyses ranged from 12 to 68 pprn compared to the author's computed range of 10 to 80 ppm. The average amount of oxygen found in our irons was about 20 pprn and changes in the silicon content of the iron from 1.32 to 2.35 pct had no consistent effect on the oxygen content of the iron. The gas determination specimens were poured in split steel molds that produced a clean pin, 3/8 in. diam and 2 in. long. Because freezing was almost instantaneous, the pins were entirely white iron (nongraphitic). In the early stages of the investigation, the pins were transferred to a mercury-filled trap system immediately after pouring. This was done to collect gas evolved between pouring and analysis. However, it was found that during storage for 4 weeks gas evolution was negligible. Because the vacuum-fusion analysis was usually completed within 4 days of pouring, pins from later heats were not stored in the mercury-trap system. We found some evidence that cast iron picks up oxygen during long storage, because of rusting. Earlier work by the British Cast Iron Research Association has shown that cast irons may be stored for a long time without significant change in their oxygen content. The practical significance of this study (and our own) would be in the improvement of cast-iron quality. Has the author investigated this aspect and reached any conclusions on the effect of oxygen on the mechanical properties of cast iron? The second phase of our study was to determine the properties of the test bars poured simultaneously with the gas analysis specimens. We realize that there may be complicating factors attendant in this procedure.21 Results from many test specimens measuring chill depth, transverse flexure and deflection strength, spiral fluidity, and sensitivity to hardness of gray irons ranging from 12 to 68 pprn oxygen showed that the lowering of transverse strength was the only significant undesirable effect of high oxygen content. A statistical study of the chill test results21 showed that the iron containing 22 to 46 pprn oxygen had forced chill depths that were 2/32 in. below the expected value from their composition, and irons containing less than 16 ppm oxygen had forced chill depths averaging 1/32 in. greater than the expected chill depth. Higher oxygen contents, within the range of 12 to 68 pprn did not increase forced chill depth. With the wedge tests, there was a good linear relationship between carbon equivalent of the irons and their chill depth. The results indicated that oxygen contents below 50 ppm in the iron did not affect chill depth. With 50 to 70 ppm oxygen in the iron, oxygen appeared to have a slight graphitizing tendency. These results are in disagreement with the common belief in gray iron foundries that "oxidized irons" produce high chill depths. It would be appreciated if the author would comment on this subject. Gustaf Ostberg (author's reply)—In Fig. 1 the legend of line I should read 2 pct C, 1 pct Si. The author wishes to thank Mr. Loria for calling attention to his later work, which was published after the present paper was concluded. The range of oxygen contents quoted seems to agree well with the author's values. The lack of response to variations in silicon content is probably due to the fact that the oxygen content in most cases was below the saturation level. The absence of temperature dependence, even in the case of saturation, is understandable if the difficulty in formation and escape of the deoxidation products is taken into account.

Jan 1, 1960

By Paul D. Merica

One of the most useful, and at the same time least commonly used, methods of thermal analysis for the determination of transformations in metals and alloys consists in the recording of the time intervals required for successive increments of temperature change during heating or cooling, the temperature of the furnace containing the specimen being altered at a uniform rate. The curve obtained by plotting these time intervals as a function of the mean temperature of the specimen durnig the interval is called the inverse-rate curve. It is probably due to the fact that no simple and convenient method has apparently been available for the measurement of the successive time intervals that this method has not been so generally used as, for example, the differential method, for which several types of automatic or semi-automatic apparatus have been designed. Whenever this method has been used, the intervals have usually been measured with the use of a chronograph; its operation as practised at the Bureau of Standards1 is as follows: The temperature of the specimen is measured by a thermocouple and a dial potentiometer. The operator sets the potentiometer at successive values of the electromotive force differing by equal increments, usually 0.02 millivolt, and records the exact instant on the chronograph, by pressing a contact key, at which the galvanometer coil passes through its null position. Two-second intervals are also recorded on the chronograph record, and the number of seconds elapsing between successive signals is afterward counted from the record and plotted as a function of the electromotive force or of the temperature. This is an admirable method and by it most minute thermal arrests may be detected, but it requires a good chronograph, which is generally difficult to obtain, and the time of one operator during the recording and, subsequently, to read the intervals from the record; the latter operation often takes from one to two hours. There is here suggested a simple, convenient, and, it is believed, equally accurate method of recording the successive time intervals, by which the

Jan 1, 1921

By William I. Gardner

Optimum design of a structure obviously requires a thorough knowledge of the materials to be utilized in its construction. When the structure is a tunnel, a most important element in its design and construction is the geology. As a tunnel may be many miles in length and at depths of hundreds or thousands of feet, we face a real problem to meet the needs of the designer and builder. How can we determine the properties of our construction materials in this situation? Engineering geology has had a formidable challenge to meet the requirements of conventional excavation methods; the advent of machine methods for rapid excavation compounds the requirements for more detailed and more precise geological knowledge of the tunnel site. This chapter will discuss the means now at our disposal to meet the challenge to produce the required data on the tunnel site in the preconstruction stage. Our considerations will be directed towards construction of a free-flow tunnel, primarily in fractured rock formations, without any requirements for the rock mechanics type of in-situ tests that might be made for a pressure tunnel or for a large opening for an underground power plant. In essence the investigation must determine: (1) The geologic conditions affecting the type of construction equipment and excavation method of the rock to be broken and removed. (2) The quantities of water and gas to be encountered. (3) The strength and stability of the material surrounding the bore and its need for support and lining. GEOLOGICAL FACTORS AFFECTING TUNNEL DESIGN AND CONSTRUCTION The engineer or contractor may classify the rock as either competent or incompetent or more pointedly as "good" or "bad" ground. The geologist may bestow a precise petrographic name upon the rock, such as granodiorite or indurated tuff breccia or name the formation, as Mancos shale, for

Jan 1, 1970

E. W. King, Bozeman, Mont.: The form of measuring up ore in sight looks very plausible, as illustrated in the paper of Mr. Emmons, but from my experience of many years of mining in Montana and Nevada, I have found it is very hard to measure up anything nearer than a guess of what you have in sight, except in the case of a true vein, or a flat vein where the boundaries are well defined. I have been interested in several miues with Dr. A. R. Ledoux, and I know that my foreman and myself, going into the mines and using our best judgment, could seldom see more than 30 days' supply actually in sight, and yet we were running from 100 to 250 tons a day, and keeping it up year after year. Prof. John D. Irving, New Haven, Conn.: I understand from Mr. Emmons that this is a method which has been found applicable in the copper-mines in Tennessee, where the record could be made with a good deal of accuracy, and where the work in the mines allowed the necessary development to be done, so that the record could be kept up. I do not think there was any intention in his mind to imply that this was applicable to all cases, especially such as Mr. King has mentioned. President Charles Kirchhoff, New York, N. Y. : I think the point is that the paper impresses the necessity for doing it where the possibilities exist. There has been too little attention given to this very matter, particularly in the United States; but I think our English friends are following it very much more zealously, and the demand for it there is possibly greater than it is here, because English boards of directors handle mines that are often very much further away than our own are, and the English public and the English engineers generally are very much more insistent upon seeing how much longer current dividends are going to last, or current assessments are going to continue.

Jan 1, 1913

By AIME AIME

FOR the development of a mine, a shaft of small cross-section is usually sunk, of no larger size than is absolutely necessary. After the mine has been developed and put on a production basis it is a common practice to sink a shaft of larger cross-section for hoisting and use the original shaft for the handling of men and material into the mine. While that ar¬rangement is usually expedient, the small size of the supply cages presents a problem in the handling of ma¬terial. Where a cage is, say, 4 by 4 ft., which is not an uncommon size, all lengthy and bulky material must be handled piece by piece several times from the supply department to the underground stations. Thus drill steel and timbers over 4 ft. long will be loaded on cars at the supply department and wheeled to the shaft, where each piece must be unloaded from the cars and stood up in the cage. They are then lowered to the shaft station, unloaded piece by piece and placed in cars, run to the supply station and again unloaded and stored until called for. In such a case handling becomes a major item in the cost of supplies.

Jan 1, 1930

By Sam Tour

OF the new alloys achieving commercial prominence during the year, an aluminum-silicon magnesium casting alloy, which is similar in many respects to the 4 per cent copper alloy, developed about 1921, which has attained such a wide field of service, may be mentioned. The new alloy, like the old, is a heat-treatable type and develops about the same physical properties. The alloy casts easily and is relatively insensitive to high pouring temperatures. Its ability to produce substantially leak- proof castings is noteworthy. A second casting alloy development is the new Aluminum Co. of America No. 132, "Lo-Ex" piston alloy, a result of nearly eight years of research. The alloy contains about 14 per cent silicon and varying amounts of nickel, copper, and magnesium. It exhibits a low coefficient of expansion and thus permits small piston clearances. Its lower specific gravity is a further advantage.

Jan 1, 1932

By L. C. Campbell

The purpose of any accident-prevention program is the curtailment or entire elimination of injuries and fatalities. It is a job that is never finished in the coal-mining industry. Day by day, on shift and off shift, men are exposed to injury and death in varying numbers. Seldom is it possible to lock up at the end of the shift and leave a mine plant in the care of a sleepy watchman, as can be done at most manufacturing plants. Even on off shifts there are maintenance and supply crews, coal cutters, pumpers and ventilation men exposed to danger. The prevention program of The Koppers Coal Co. recognizes two primary facts: First, no program can be successful without the full support of the management and complete knowledge of the job at hand on the part of every supervisor. Second, and equally important, is the full cooperation of every employee in observing the safety rules and practices set up by the management. Conscious day-to-day concern for his safety by the individual worker is the longest stride toward a good safety experience. How to accomplish the education of the individual worker and supervisor for safety is the problem of The Koppers Coal Co., as it is the problem of all coal companies. Safety Rules A simply stated set of Safety Rules and Practices for the government of employees is the starting point with The Koppers Coal Co. There are but 13 of these rules, which are short, easily understood and followed by a campaign of education and inspection. Each employee receives a set of these Safety Rules and Practices and signs a receipt for them, which is bound in at the back of the booklet, and this receipt becomes a part of his employment record. These rules and practices are as follows: Introduction The following rules have been compiled for the safety of employees and are established according to rules number one and number two of the official bulletin

Jan 1, 1940

By L. C. Campbell

The purpose of any accident-prevention program is the curtailment or entire elimination of injuries and fatalities. It is a job that is never finished in the coal-mining industry. Day by day, on shift and off shift, men are exposed to injury and death in varying numbers. Seldom is it possible to lock up at the end of the shift and leave a mine plant in the care of a sleepy watchman, as can be done at most manufacturing plants. Even on off shifts there are maintenance and supply crews, coal cutters, pumpers and ventilation men exposed to danger. The prevention program of The Koppers Coal Co. recognizes two primary facts: First, no program can be successful without the full support of the management and complete knowledge of the job at hand on the part of every supervisor. Second, and equally important, is the full cooperation of every employee in observing the safety rules and practices set up by the management. Conscious day-to-day concern for his safety by the individual worker is the longest stride toward a good safety experience. How to accomplish the education of the individual worker and supervisor for safety is the problem of The Koppers Coal Co., as it is the problem of all coal companies. Safety Rules A simply stated set of Safety Rules and Practices for the government of employees is the starting point with The Koppers Coal Co. There are but 13 of these rules, which are short, easily understood and followed by a campaign of education and inspection. Each employee receives a set of these Safety Rules and Practices and signs a receipt for them, which is bound in at the back of the booklet, and this receipt becomes a part of his employment record. These rules and practices are as follows: Introduction The following rules have been compiled for the safety of employees and are established according to rules number one and number two of the official bulletin

Jan 1, 1940

By AIME AIME

HARVEY MUDD, mining engineer and distinguished citizen, has achieved that balance between professional and civic activities for which many of us strive but few attain. His able direction of mining operations is known to many Institute members but perhaps few know that he was in 1936 recipient of the annual award given by the City of Los Angeles to that citizen who contributed the most valuable and unselfish service to the community. Mr. Mudd was born in Leadville,

Jan 1, 1944

By AIME

A NATIVE son of Salt Lake City. David Douglas Moffat has contributed greatly to both the mineral industries and civic progress in the State of Utah. He was born in 1880 and his whole life bas been intimately associated with mining and milling. His father, one of Utah's pioneer mining men, was superintendent of a mill at Park City. When Moffat was only 18 years of age he went to Philipsburg Mont., where he spent several years as a machinist, and later as master mechanic for the Granite Bi-Metallic Mining Co. He returned to Park City in 1903 as master mechanic and night mill foreman for the Ontario Silver Mining Co. After a few years of varied experience he became, in 1910. general foreman of the Boston Consolidated Will at Garfield, Utah.

Jan 1, 1947

By E. C. Roberts

TO facilitate some recent microscopic investigations it was necessary to devise special mounting techniques for the polishing of two quite different metallographic specimens. These techniques are extremely simple and are submitted for whatever value they may be to other investigators. The first specimen mount proved very satisfactory for the study of untempered martensite. Since it was undesirable to heat the specimen, lucite or bakelite mounting materials could not be used in the conventional manner. A cold mount was made by drilling a hole of the same diameter as the specimen in a cylindrical piece of polystyrene then press- ing the steel specimen into the hole on an ordinary vise. A prefabricated disk of lucite should work equally well. The only precautions necessary are that the hole be drilled out cleanly and the piece of steel be pressed into the plastic uniformly, otherwise the mount will crack. The second type of mount was required for the study of slag specimens by reflected light. Mounting these specimens in bakelite and then attempting to rough finish the surfaces on graded emery papers resulted in a considerable amount of chipping and breaking out of the slag particles. This made further satisfactory polishing almost impossible. It was found, however, that if the bakelite-mounted specimen was first rough finished to a point where a good specimen surface became visible, the interstices in the specimen surface could be filled and the polishing completed. This filling was accomplished by placing a small amount of lucite powder in the bottom of the steel specimen mold then reinserting the bakelite-mounted specimen on top of the lucite powder. Reheating the mold to the proper temperature and applying the required pressure resulted in the formation of a thin disk of lucite on the bottom of the bakelite specimen. By carefully grinding the lucite away a uniform surface including the slag specimen was obtained and further polishing was unhampered by slag disintegration.

Jan 1, 1951

By J. W. Sandelin, L. S. Birks

The group five metals, vanadium, niobium, and tantalum all show cold-rolled textures of {100)(011) and {112)(0ll) with a preference for the (100) in vanadium and niobium and for the {112) in tantalum. Recrys-tallization texture of (100) and (111) was reported1 for vanadium after annealing (no temperature stated). For tantal~m ,~ annealing below 1200°C strengthened the (112) texture but the (111) texture increased and was predominant as the annealing temperature was raised to 2500°C. Annealing niobium up to 1100°C strengthened the ( 100) texture and developed a weak (111) texture.' In the present work niobium has been annealed up to 2000°C. Nearly 70 pct of the grains showed {111) texture with only a weak (112) component and an insignificant (100) component remaining. In addition, double-crystal rocking curves were used to follow the increase in crystal perfection of the grains with increased annealing time. Material and Treatment. Samples i by 4 in. were sawed from & -in.-thick cold-rolled niobium sheet obtained from Wah Chang. Chemical analysis of the material showed it to be 99.4 pct pure with tantalum as the major impurity. Individual pieces were annealed for 2, 15, 30, and 60 rnin in a vacuum of 10'* Torr using an rf generator. They were etched until the grain boundaries were well-defined, Fig. 1. Average grain size varied from 1 mm for 2 min annealing to 2 mm for 60 rnin annealing. Experimental Results. Preferred Orientation. The orientations of 97 of the 117 grains in the specimens of Fig. 1 were determined by back-reflect ion Laue patterns. A General Electric 10-cm-diam cylindrical camera was used rather than the conventional flat camera in order to record more of the low-index spots. The method proposed by Forest, Barton, and schieltz4 was used to transform the cylindrical film patterns to standard stereographic projections. Table I gives the compilation of data. Even 2 rnin anneal at 2000°C is sufficient to yield a strong (111) preferred orientation, and the percentage of grains with this orientation increases steadily with annealing time at the expense of all other orientations. Crystal Perfection. X-ray topographs were taken of each specimen in both the (111) and (112) orientation using the method described by Birks and Grant.' As the anneal time increases, the grains become larger and the individual reflections become slightly more uniform in intensity, indicating an increase in crystal perfection. For a more quantitative measure of crystal perfection, it was necessary to measure the double-crystal rocking curve. The spectrometer employed was a Gaertner instrument of Compton design. LiF was chosen for the first crystal because the (400) reflection with d spacing of 1.05 AU is a good match to the (222) niobium reflection with d spacing of 0.95 AU. CuKp radiation was used in order to further reduce the d spacing mixmatch correction.' A variable aperture was placed between the LiF and the niobium specimen so that a single grain or even a small portion of a grain could be examined. Fig. 2 shows typical rocking curves for the four annealing times. For the 2-min specimen, a single peak is observed with 10' of arc full-breadth at half maximum. As the annealing time is increased to 15 or 30 min, several sharper peaks of 40 to 80" breadth can be seen within a single grain. After 60 rnin anneal only a single peak of about 30" is observed. Table I1 shows the corrected rocking curve breadths and the dislocation densities, ND. The latter were calculated from the equation7 where W is the corrected rocking curve breadth at half maximum in radians and b is the effective Burger's vector. For (110)(111) slip in niobium, b is 2.86 AU. Discussion. The annealing of cold-rolled niobium at 2000°C causes rapid preferential growth of grains with {ill} orientation. After only 2 rnin annealing time, 35 pct of the grains have the (111) orientation, and after

Jan 1, 1968