Search Documents

• As part of $850,000 granted by the House Appropriations Committee for development of manganese in the U.S., the Bureau of Mines will build a pilot plant at Artillery Peak, Ariz., for development of low grade manganese ores. • The historic Argo tunnel and mill in Idaho Springs, Colo., will reopen shortly for the mining of uranium. The Uranium Co. of America has acquired control of the tunnel and mill and 12 nearby mining properties. J. H. Rodgers and G. C. Ridland will manage the operation. •The opening of a new 4000-ton per day coal mine in Washington Co., Pa., and the reopening of another mine of the same capacity in Fayette Co. has been announced by the H. C. Frick Coke Co. They'll help meet added war demands. •A 7000 bbl per day commercial synthetic liquid fuel plant, making gasoline from natural gas at Brownsville, Texas is being operated by the Carthage Hydro-col Corp., a Texaco subsidiary. The gasoline is produced by the Hydrocol process, chemically similar to the Fischer Tropsch process, but differing mechanically in several ways. To operate the process it has been necessary to build an oxygen plant producing 95 pct pure oxygen in quantities equal to U. S. production of commercial oxygen in 1946. •Over 96 pct of the class of 1950 at Montana School of Mines are now employed,, in industry, and they're scattered from MIT to the island of Cuba., • Cobalt, heretofore almost entirely imported, will soon be produced in Idaho. The Calera Mining Co. is building a 600-ton mill in which a cobalt and copper concentrate will be obtained from Idaho ores. •Plans for mining iron ore on the Conarky Peninsula in French Guinea, (an ECA project) call for equipment purchases as follows: 8 wagon drills, electric shovel for mining, conveyor for the port, 8 trucks, wrecker, 2 tractors, as well as miscellaneous accessories and spare parts. •A low-grade lead-zinc mineralization, located east of any known ore bodies in Utah's East Tintic district, has been located by a 2000-ft wildcat USGS drill hole. * Higher-than-going rates have been authorized by the Munitions Board for its stockpile program, where domestic production of scarce materials is low or uneconomical. Payment in excess of 25 pct over the foreign price is now permitted. •A new self-centering conveyor roll, developed by Carnegie-Illinois Steel, is expected to revolutionize materials handling. It completely eliminates the necessity for sideguides to keep materials on a conveyor. See P. 1028. •Great Britain's socialized coal industry employs twice as many miners, but produces less than half as much coal as America's coal industry. last year, British mines produced 28 million fewer tons of coal than the output of the same ,mines in 1939. Absenteeism amounted to a big 12 pot of working time. • Labor market conditions have tightened on almost a country-wide scale. Only 4 out of 143 major labor market areas have a substantial surplus -- less than half the total for May. Growing scarcities of skilled labor are in evidence.

Jan 10, 1950

By Charles Trotter

AN instrument has recently been developed for determining the inclination and azimuthal direction of boreholes. This instrument is known as the Tro-Pari Instrument and is the invention of C. Trotter and G. Pajari of Sudbury, Ontario. DESCRIPTION The instrument is characterized by a unit mounted in gimbals and provided with a clockwork mechanism to clamp a compass to indicate azimuthal direction and simultaneously to clamp the unit in its plumb position to indicate inclination (Fig I). By means of a timing ring suitably calibrated in 5-min divisions, the unit may be set to lock after a lapse of time sufficient to allow the placing of the instrument at the desired point in the drill hole where readings are to be taken. The maximum time lapse obtainable with the instrument designed for use in EX or AX size holes is 1 hr 30 min which is considered to be ample time to lower to the greatest depths that may be drilled with this size of equipment. Larger sizes could be developed for larger diameter holes such as BX and NX sizes or the larger oil-well sizes and a correspondingly greater time lapse could be provided for. Up to the present time only the EX-AX size has been built. OPERATION Assuming a borehole is to be surveyed at 1000-ft depth and assuming it will take 30 min to lower the instrument to this depth, the timing ring is rotated through seven divisions which represent a time lapse of 35 min (5-min leeway) and is then returned to its zero position. This operation imparts energy to a spring which drives the clockwork mechanism. Simultaneously the compass needle is freed to swing to its magnetic north-south position and the encased mechanism is freed to hang plumb within a semicircular portion of the frame which is graduated in degrees after the fashion of a protractor. This semicircular protractor portion has a V-shaped notch at each degree division of its inner periphery. The instrument, now in its free position, is inserted in a bronze container made to suit the size of hole to be surveyed (Fig 2). Soft rubber washers are provided within the container to prevent undue shock. The container is connected to the drill rods with three 5-ft lengths of brass or aluminum alloy rods separating it from the steel rods in order to prevent distortion of the magnetic field. The assembly is then lowered to the desired point where readings are to be taken and is allowed to remain at rest until a period of time has elapsed slightly in excess of the time for which the timing ring was set. In the example cited above, when the 35 min has elapsed the compass needle is locked in its north-south position and the protractor locking pin is extruded and locks in the V notch opposite its plumb position. The device may now be removed from the borehole and it will remain in this locked position in spite of jarring or shak-

Jan 1, 1947

By E. Maxwell, C. J. Bechtoldt, H. C. Vacher

IN the course of an investigation of the properties of metals at low temperature there was occasion to determine the constitution of four iridium-osmium alloys. There is very little information in the literature1 on the constitution of synthetic Ir-0s alloys. Zvyagintzev' s has made a comprehensive study of different natural Ir-0s alloys and concludes that alloys containing more than 32 pct 0s have the close-packed hexagonal structure of osmium, whereas those containing less than 32 pct 0s have the face-centered cubic structure of iridium. The alloys studied in this work were prepared by the American Platinum Works, Newark, N. J., and were received in the form of fragments approximately 1.5 mm average diameter. The fragments had been obtained by crushing ingots made by fusing charges of iridium and osmium under an arc and air cooling. The ingots were not given a homogenizing heat treatment. Sample fragments Table I. Results of X-Roy Diffraction and Microscopic Examinations Phases Present as Determined by X-ray Diffraction Osmium Alloy Close- Iridium Face- Packed Centered Osmium, Iridium, Hexagonal Cubic Mlcro- WtPot Wt Pct Structure Structure scope 0 99.9 None Present 1 23.6 76.4 None Present 1 38.7 61.3 Present Present 2 59.4 40.6 Present Present 2 79.0 21.0 Present Not detected 2 99.9 0 Present None 1 Note: Chemical analyses of the iridium, osmium, and alloys were furnished by the American Platinum Works. of the iridium and osmium used in making the alloys also were included. Several fragments of each metal and alloy were examined microscopically and by X-ray diffraction. For the X-ray method the fragments were crushed further to pass a 270-mesh screen, then sealed in evacuated fused-silica tubes, heated to 1100°C for 18 hr, and allowed to cool in the furnace. Powder X-ray diffraction patterns were obtained from the annealed fragments by means of a Norelco camera having a diameter of 114 mm, and unfiltered cobaIt radiation. For the microscopic examination several fragments in the as-received condition were mounted in Melmac, (American Cyanamid Co.) and ground using the conventional series of abrasive papers. The polishing was done with 0-2 diamond abrasive on a Microcloth (Buehler Ltd.) lap, wet with xylene. After polishing, the surface was etched electrolytically in a 10 pct solution of chromic acid or in a 10 pct solution of potassium cyanide. Both reagents attacked the osmium-rich constituent, whereas the iridium constituent was attacked slightly by the chromic acid reagent and not noticeably by the potassium cyanide reagent. The results of the X-ray diffraction and microscopic examinations are summarized in Table I. Fig. 1 shows the microstructure of a 21 pct Ir-79 pct 0s alloy. The results indicate an appreciable solid-solu-bility range of osmium in iridium as was reported by Zvyagintzev.' The solid-solubility range of iridium in osmium is more restricted, apparently less than 21 pct Ir. This implies a large range of composition in which two phases can coexist that was not reported by Zvyagintzev.

Jan 1, 1955

By Charles Trotter

An instrument has recently been developed for determining the inclination and azimuthal direction of boreholes. This instrument is known as the Tro-Pari Instrument and is the invention of C. Trotter and G. Pajari of Sudbury, Ontario. Description The instrument is characterized by a unit mounted in gimbals and provided with a clockwork mechanism to clamp a compass to indicate azimuthal direction and simultaneously to clamp the unit in its plumb position to indicate inclination (Fig I). By means of a timing ring suitably calibrated in 5-min divisions, the unit may be set to lock after a lapse of time sufficient to allow the placing of the instrument at the desired point in the drill hole where readings are to be taken. The maximum time Lapse obtainable with the instrument designed for use in EX or AX size holes is I hr 30 min which is considered to be ample time to lower to the greatest depths that may be drilled with this size of equipment. Larger sizes could be developed for larger diameter holes such as BX and NX sizes or the larger oil-well sizes and a correspondingly greater time lapse could be provided for. Up to the present time only the EX-AX size has been built. Operation Assuming a borehole is to be surveyed at 1000-ft depth and assuming it will take 30 min to lower the instrument to this depth, the timing ring is rotated through seven divisions which represent a time lapse of 35 min (5-min leeway) and is then returned to its zero position. This operation imparts energy to a spring which drives the clockwork mechanism. Simultaneously the compass needle is freed to swing to its magnetic north-south position and the encased mechanism is freed to hang plumb within a semicircular portion of the frame which is graduated in degrees after the fashion of a protractor. This semicircular protractor portion has a V-shaped notch at each degree division of its inner periphery. The instrument, now in its free position, is inserted in a bronze container made to suit the size of hole to be surveyed (Fig 2). Soft rubber washers are provided within the container to prevent undue shock. The container is connected to the drill rods with three 5-ft lengths of brass or aluminum alloy rods separating it from the steel rods in order to prevent distortion of the magnetic field. The assembly is then lowered to the desired point where readings are to be taken and is allowed to remain at rest until a period of time has elapsed slightly in excess of the time for which the timing ring was set. In the example cited above, when the 35 min has elapsed the compass needle is locked in its north-south position and the protractor locking pin is extruded and locks in the V notch opposite its plumb position. The device may now be removed from the borehole and it will remain in this locked position in spite of jarring or shak-

Jan 1, 1949

By R. D. Longyear

[Some Problems Involved in the Interpretation of Diamond-drill-hole Sampling and Surve ing (paper by J. J. Collins, Mining Tech., Jan. 1946). ............... I Geologic Interpretation of Magnetic Exploration on the Mesabi Range, Minnesota (paper by R. H. B. Jones, Mining Tech., July 1946) ................... 2] DISCUSSION R. D. LONGYEAR.*-Mr. Collins is to be commended very highly for the brief summary he has made of the currently used methods of taking diamond-drill sludge samples and the principles involved in evaluating the results. This paper should stimulate further discussion and research on this vitally important problem. It is particularly imperative that geologists and engineers know when assay results on sludge recovery can be accepted quantitatively and when they must be considered only qualitatively. In most cases where the sludge recovery is less than 95 per cent or more than 125 per cent, it is safest to consider the assays as of qualitative value only. Certain cases, however, are known where a relatively small proportion of the sludge sampling will give a reasonably accurate measure of the value of the total sample. One such case is ore in which the valuable mineral is of approximately the same specific gravity as the waste mineral, such as chalcopyrite in a massive pyrite body. The essential point is to determine the degree of accuracy of sludge sampling in any given drilling project and to weigh the results accordingly. It should be emphasized, however, that sludge sampling can be made reliable in many localities where careless practice produces unreliable results. In many instances, it is desirable to empty the core barrel in the core shack instead of at the drill, so that the engineer can examine the core as it first comes from the core barrel. It should be pointed out, however, that the drill * E. J. Longyear Co., Minneapolis, Minnesota. runner should be permitted to study the core to guide his future drilling. It is hoped that with the return of more normal conditions after the war geologists, engineers, contractors, and manufacturers will be able to carry on more research along the lines of improved core-barrel design and drilling technique with the objective of increasing core recovery so as to eliminate as far as possible the necessity of relying upon sludge samples. H. M. ROBERTS.*-Whoever in the future will have to do with the search for ore bodies and their exploration will have frequent occasion to refer to the clear and comprehensive summary on diamond-drilling methods by John Collins. His review of the experience of the last 40 years in this technique is invaluable. As Dr. L. D. Ricketts wrote in 1932, "The principles on which an art is founded are usually few and necessarily basic in nature, but he who wishes to achieve the power to select his aides and give success to important undertakings that may be intrusted to him in the future must ordinarily undergo years of drudgery in order to gain the experience that will enable him to distinguish such fundamentals through the haze of reinforcing detail that clothes and tends to disguise them."[t] Ricketts went on to say that since the beginning of the century there has been much

Jan 1, 1946

By R. S. Hoch, Roy A. Bobo

Maintenance of desirable plastic flow properties of weighted drilling muds may be greatly simplified by use of centrifugal classification to control the drilled solids content. The new application of a decanting type centrifuge to separate and reject the low density solids from the weighting material results in a drilling mud of greatly improved quality with lower values of yield and rigidity. Its practicality and economy has been proven in field operation. The degree of separation of light and heavy solids is not limited by the machine, but by the particle size distribution of the solids in the mud. Removal of the low density component of drilling mud that makes chemical treatment necessary permits a marked reduction in chemicals. The main uses of the centrifugal process are the treatment of muds while drilling, the reclaiming of discorded muds, cleaning up of workover muds, and the reduction in lime content of mud for completion. INTRODUCTION Drilling mud in any circulatory system is made viscous and difficult to pump by gradual accumulation of drilled solids which pass through the shale shaker and are continually reground. In a weighted mud containing a large proportion of barite by volume, the amount of drilled solids that may be tolerated is greatly reduced. Much effort has been expended to control by chemical treatment the effects of such solids. Though chemical treatment is quite effective, the time eventually comes at deeper depths after enough drilled solids have entered the system when a portion of the mud must be discarded and replaced with water and more weighting material. Once begun, this process is generally continued at frequent intervals with resultant high maintenance costs. At the termination of drilling, mud highly contaminated with light solids and spent chemicals is poorly suited for completion operations.' It is likewise limited in utility for other drilling operations. This investigation was conducted for the primary purpose of determining an acceptable mechanical means of removing the lightweight solids from weighted drilling muds in order to maintain viscosity at a minimum. A decanting type of centrifuge was selected from the various possible methods of mechanical separation. The centrifugal process has been employed in this country for this purpose in central mud reclamation systems in California in earlier years. It also was used for treatment of weighted muds on the Gulf Coast.' In more recent years only sporadic attempts have been made to employ it in the field on weighted muds. DISCUSSION OF PROCESS Selection of Apparatus Two factors favor mechanical procedure for the separation and removal of drilled solids or clays from the mud circulatory system. First, the greater specific gravity, 4.1 to 4.3, of the barite would promote more rapid settling than the clays whose specific gravity range is from 2.5 to 2.7. Second, the relative coarseness of the barite particles also facilitate faster settling of this phase. A decanting type of centrifuge was preferred for this process over other possible methods for these reasons: 1. Requires no costly additives or excess dilution. 2. Centrifugal force affords greatly accelerated separation as compared to gravity.

Jan 1, 1955

By John B. Campbell, George G. Binder, Loren H. Jenks

Conventional methods of producing crude oil generally leave in the depleted reservoir 1 to 3 bbl of oil for every barrel brought to the surface. This paper describes a field test which explores the possibility of using gas-driven liquid propane to improve oil recovery efficiency. Laboratory theoretical and experimental studies leading to the field test indicated that low residual oil values could be obtained using limited amounts of propane driven by gas. The field test involved (I) repressuring the reservoir to the vapor pressure of liquid propane, (2) injecting the liquid propane, and (3) injecting dry natural gas to drive the propane and oil to the producing wells. Considerable preliminary work, including new drilling, work-overs, and a pressure survey was necessary. During the test, oil production rates have averaged about nine times the final primary rates. The field average GOR is still below the pre-test value. Oil recovery to date is 112,000 STB. About one-third of the 143,-000 bbl of propane injected has been produced to date. Results of the C-2 block test are encouraging and larger, more definitive field projects ore indicated. INTRODUCTION The cost of finding new crude oil reservoirs continues to increase. Today the oil industry is drilling more and deeper wells and making fewer big discoveries. Nevertheless, the demand for oil and oil products increases each year. It is natural that oil companies, faced with this situation, concentrate on recovering more of the oil existing in our known crude oil reservoirs. There is room for much improvement. For every barrel of oil brought to the surface by present day methods of producing crude oil, generally 1 to 3 bbl are left behind in the depleted reservoirs. The "unrecoverable" oil in petroleum reservoirs is largely "trapped" by capillarity. Since flushing with a solvent is exceedingly effective in combatting oil loss due to capillarity, much effort in this direction has been made in recent years1,2,3,4,5. Liquefied petroleum gas (LPG) has been suggested as a relatively inexpensive. abundant, easily recoverable solvent for crude. Some operators have observed striking responses in oil recovery at production wells offsetting input wells in LPG storage reservoirs6,7,8. In spite of the low unit cost of LPG, however, it is uneconomic in general to inject a volume of LPG into a reservoir to remove a like volume of oil. A modification of solvent flushing in which a limited quantity of liquid propane is gas driven through a reservoir appears capable of recovering much more than 1 bbl of oil per barrel of propane injected. Also, most of the propane injected should be recoverable for sale or re-use. Since such a process could well have widespread and profitable application, The Carter Oil Co. is making an extensive evaluation of the technique's possibilities. Laboratory development of the gas-driven propane recovery technique was sufficiently encouraging to justify testing in the field. Since 1952, the Production and Research Departments of The Carter Oil Co. have cooperated in a field test in the C-2 Block leases of the

Jan 1, 1958

By W. K. Hardy, H. H. Stadelmaier, L. J. Huetter

The ternary system Co-Sn-C was studied in the cobalt-rich region. The liquidus projection ulas established and two fonr -phase reactions were found. An isothermal section at 950°C was worked out. In the region studied the following phases were observed: cobalt-rich solid solution, graphite, binary compound y -cobalt-tin, and a ternary compound. As a result of the limited solubility of carbon in liquid cobalt-tin alloys, the investigation was limited to the cobalt-rich region. Tin contents up to 32 at. pct were studied. Cobalt of 99.99 pct purity, tin of 99.97 pct purity and synthetic graphite of 99.93 pct minimum purity prepare the alloys. Carbon determinations of all alloys were obtained by gas volumetric analysis. Samples were investigated microscopically and by X-ray diffraction using CoK, and FeK, radiation. Cooling curves were obtained with a number of alloys to determine the temperature of the four-phase reactions. The thermocouple was calibrated with the melting points of high-purity silver and copper. In the region studied the following phases were observed: Cobalt-rich solid solution (face-centered cubic) Graphite. Binary compound y (solidifies congruently at composition Cop~n)'. Ternary compound k which is face-centered cubic with superlattice and nonferromagnetic.' In Fig. 1 the fields representing the projections of the liquidus surfaces were determined by microscopic investigation and are labled by their primary phase. In the field labled C graphite is the primary phase. During solidification in this field much of the primary graphite was expelled through the surface of the melt. It could not always be established microscopically whether the remaining graphite was primary or purely eutectic. Therefore it was not possible to determine accurately the boundary curve which drops from the binary eutectic el at 1309 "~~ to the point of the four-phase reaction at F. The ter-nary carbide is the primary phase in the field labled k. To the right of this field the primary graphite is consistently nodular whereas flake graphite is observed at tin contents somewhat below F. The ternary carbide does not appear to solidify congruently. The graphite is attacked in a peritectic reaction along the boundary between k and C. Thus no graphite is observed in alloys in the k field. In alloys right of the boundary between k and C the graphite nodules are located in the center of the k crystallites, further documenting the peritectic nature of the reaction with the graphite. A four-phase reaction was found at F and 1120 &3"C. The most likely reaction is L+ CY-Co + C — k. Below the temperature of the binary eutectic ez at 1112" a second four-phase reaction was observed at E and 1100 lt3"C. It is the ternary eutectic L — CY-Co + k + y. Figs. 2(a ) to (e) show microstructures of the ternary alloys in the as-cast condition. Fig. 2(a) shows the eutectic a-Co + C (with some primary graphite) with the carbide k in the grain boundaries. Fig. 2(b) shows primary cobalt (dark areas) and the eutectic a-Co + k which is formed along F-E.

Jan 1, 1961

By C. E. Westley, R. R. Beebe

Recent works by Plaksh et al.,1,2 Glembotsky,3 and others have renewed interest in the effects of oxidation on the surface activity of the sulfides. Since considerable supporting data are available on galena-potassium ethyl xanthate, this system is being studied at South Dakota School of Mines and Technology by contact angle measurement, using the technique of McGlashan and McLeod.4 The contact-angle method is well adapted to investigation of the influence of small amounts of oxygen on the establishment of a stable contact angle on galena in potassium ethyl xanthate solution. Samples of massive galena containing less than 0.001 pct Cu, 0.001 pct Ag, and 0.01 pct Zn are mounted in castable plastic and ground and polished manually in a glove box containing the desired proportions of oxygen and purified nitrogen. Oxygen and nitrogen contents of the test atmosphere are determined with an Orsatt analyzer. In this way a reproducible surface is created in contact with whatever oxygen concentration is desired. Water and all reagents are prepared and stored in the test atmosphere. An absorbent is used to control carbon dioxide that might be present. Final polishing is done with levigated alumina on a glass plate. The prepared sample is placed in the test solution and transferred to the contact angle apparatus in a sealed box, and the test is conducted while both sample and solution are maintained under a slight positive pressure of the test atmosphere. Table I gives the results of contact angle measurements made at various 02-Nz concentrations.5 Each value of contact angle is the average of at least six individual measurements made with different bubbles at different locations on the sample surface. A period of 20 to 25 min has been found by preliminary tests to be sufficient to permit develop- ment of maximum angle, and all measurements are made after at least this much time has elapsed. Exposure of prepared samples to pure water under the test atmosphere before exposure to the xanthate results in a small but measureable and consistent reduction in contact angle. This is particularly true in the oxygen-deficient atmospheres; for example, at 2.2 pct O2 such water contact reduces the average angle about 8" from that obtained by immediate testing in xanthate. The general trend of increasing contact angle with increasing oxygen concentration corresponds to the results of Plaksin et a12 The absence of diminish-ment of contact angle at very high oxygen concentration has been attributed to the high concentration of xanthate per unit of galena surface: At oxygen concentrations below 1 pct (the limit of accuracy of the Orsatt analyzer), no contact angle is obtained. Furthermore, no contact angle is obtained at any oxygen concentration in the absence of xanthate. This result seems to be in disagreement with those cited by Plaksin.1 Further work on the interaction of galena and potassium ethyl xanthate or a similar collector as influenced by oxygen is contemplated. The true nature of the interrelation is as yet unknown. For example, it is not known whether the governing oxygen reaction is with the mineral, with the reagent, or with both.

Jan 1, 1961

By Roscoe C. Clark, Henry F. Coffer, J. J. Reynolds

A cement slurry lightweight additive has been adapted in the Conoco laboratories for use in oil well cements. This additive makes possible the use of air to lighten oil well cement slurries. Specifically, the additive consists of small clay bubbles of air having sufficient strength to resist crushing by bottom hole pressures. Clay bubble cement slurry weights can be safely reduced to 10 Ibs/gal. In addition, the clay bubbles tend to act as lost circulation materials and to provide a cement texture which should produce good perforating characteristics. Clay bubble cement is relatively impermeable. INTRODUCTION In many areas in Oklahoma, Texas, Wyoming, and California, difficulties are experienced during casing cementing operations with lost returns caused by the high density of the cement slurries. Wells in these areas are ordinarily drilled with 9 to 11 lbs/gal. drilling mud while neat cement slurries may range in densities from 14.5 to 17 lbs/gal. In these areas, cement slurry weights are at present being successfully reduced to around 12 lbs/gal. (under bottom-hole conditions) by the use of additives in the cement. Since the use of additives will decrease the strength which the cement will develop, the amount of additives which can be used must be based on the minimum cement strength which is acceptable; and thus the maximum slurry weight can be reduced. At present, the minimum tensile strength generally acceptable is 50 lbs/sq in. cured for 24 hours under bottom-hole temperature. This figure is based on laboratory tests1 and on a large number of cement jobs which have been conducted using cement which will not develop more than 50 psi tensile strength in 24 hours under bottom-hole conditions. Two additives are now in use for decreasing cement slurry weights. These are expanded perlite and/or bentonite. The density of both of these materials is greater than that of the cement slurry; however, large quantities of water may be added with these materials without producing a slurry which will settle out of suspension. It is these large quantities of water which contribute to the reduction in the slurry weight. The minimum slurry weight at present obtainable with expanded perlite and/or bentonite is approximately 12 lbs/gal. using a standard Portland cement slurry. In many areas, this weight reduction is insufficient; and returns are still lost during casing cementing operations. In many cases, the pay formation itself is fractured; and a considerable quantity of this cement is lost to the pay zone. It is therefore believed that if cement slurry weights can be reduced to as low as 10 lbs/gal., two advantages will accrue: 1. The lighter densities (10 to 12 lbs/gal.) should mitigate or eliminate lost returns during casing cementing operations. 2. Cement slurries above 12 Ibs/gal. (the present minimum limit ) should develop considerably more strength than is now being obtained. A tensile strength of 100 psi is desirable.' It is the object of this paper to describe a cement slurry having a weight of 10 lbs/gal. and capable of

Jan 1, 1955

By W. Tempelaar Lietz

The Ten Section oil field is located in the San Joaquin Valley in Kern County, California. about 12 miles southwest of Bakersfield in Township 30 South, Ranges 25 and 26 East. The accumulation is in a low relief anticlinal dome and has a productive area of approximately 2,200 acres. Discovered in 1936 as a result of seismic work, it was the first field on the floor of the Valley to obtain production. It had a small primary gas cap, and since its inception has been produced by depletion with controlled withdrawal from the gas cap to minimize blowthrough. STRUCTURE AND STRATIGRAPHY The Ten Section structure is an elongated anticlinal dome with flank dips of only about 7 degrees. A map of the field, now fully developed, and a composite log are shown in Figs. 1 and 2. Contours shown on the map are on the top of the first zone, or Marker XA as indicated on the composite log. As shown, the field has a productive closure of only some 350 feet, and there apparently is no faulting in the reservoir. The productive measures in Ten Section are of Upper Miocene age and are known as the Stevens sand. They contain thin, irregular shale or siltstone streaks which vary considerably in stratigraphic position and thickness and apparently are rather discontinuous. As a result, individual sands and shales cannot be correlated over any appreciable area, which makes it difficult to subdivide the sand body into separate zones which are distinct throughout the field. However, there are two fairly persistent siltstone bodies that at the time of development were considered to divide the productive measures into three - zones. The first, or uppermost zone is productive over the entire field and has an average thickness of 180 feet, of which some 65 per cent is sand. It had a primary. gas cap in the crestal area with an areal extent of 930 acres. The second zone has a productive area somewhat smaller than the first zone, but it did not have any original gas cap. It has an average thickness of about 360 feet, of which 55 per cent is sand. The third zone has a very limited areal extent and a maximum productive thickness of 100 feet, of which 80 per cent is sand. Recently, a deeper oil accumulation, termed the "53" sand, was discovered, but it is not discussed in this analysis. In the first and second zones the water table was at 7,980 feet subsea, while in the third zone it was at 8,080 feet subsea. RESERVOIR CHARACTERISTICS Sand Characteristics The Stevens sand in Ten Section is hard and well consolidated, and numerous wells were cored for core analysis. Core data on four representative wells are shown, plotted beside the electric logs in Figs. 3 to 6. The average porosity is 20 per cent, with porosities ranging from 15 to 30 per cent. It is estimated, from cores taken with oil base muds, that the interstitial water content is about 40 per cent. The average weighted permeability is approximately 140, with measured permeabilities ranging from 10 to 3,000 md. As might be expected with practically no correlation of individual sand

Jan 1, 1949

By C. W. Allen, B. D. Cullity, H. S. Choi

The torsional deformation of aluminum and magnesium crystals is investigated, with particular reference to the dependence of proportional limit on crystal orientation. The proportional limit is found to be governed by the average value of the resolved shear stress on the most highly stressed slip systems, but the proportional limit does not strictly obey a critical-resolved-shear-stress law. The behavior of a cylindrical single crystal stressed in tension is well known: plastic flow begins when the resolved shear stress on the most highly stressed slip system reaches a critical value. There is much less understanding of the effect of torsion on such a crystal and on the way in which the critical-resolved-shear-stress law should be applied to torsional deformation. In the present paper particular attention is paid to the dependence of plastic yielding on crystal orientation and lesser attention to the mechanism of flow after yielding has occurred. New work on aluminum and magnesium crystals is presented, and previous results obtained in this laboratory on magnesium1 are re-examined. STRESS DISTRIBUTION The problems involved in torsional deformation of single crystals are due entirely to the complexity of the stress distribution. In tension, if loading conditions are perfect, the shear stress on any particular slip plane is completely uniform over the entire area of that plane. In torsion, on the other hand, the stress on any selected plane in a particular direction varies not only from center to edge of the specimen but also around its perimeter. It is convenient to express the stress at any point in terms of t0, which is the shear stress acting at the surface of a cylindrical specimen on a plane normal to the axis and in a direction tangential to the cylinder. At point P of Fig. 1 this stress acts in the direction of axis 2 and is given by To = 2T/pr3 [1] where T is the applied torque and r the specimen radius. This stress can be resolved on any chosen slip system, and details are given in the Appendix. Let P be the point on the specimen surface where the stress is to be evaluated; P is defined by its angular distance A from an arbitrary reference line through 0 normal to the axis. his line is usually taken as the direction of incidence of the X-ray beam used to determine the crystal orientation.) Then the shear stress t, acting at P in direction Dona plane whose normal is N is given by Ts/TO = sin ? 0, cos ?d sin (?0, - ?) + cos ?, sin ?d sin (?d - ?) [2] where 0, and Od are the angles between N and D, respectively, and the axis, ?0 and ?d are the angles between the projections of N and D, respectively, on the transverse plane and the reference line through 0. By means of Eq. [2], the stress 7, acting in any given slip direction can be computed. In the previous work on magnesium1 only gross slip tangential to the specimen surface was considered, and this

Jan 1, 1963

By A. H. Daane, J. F. Haefling

BECAUSE of the wide use of platinum in industry and research, the physical properties of this metal, including its vapor pressure, have been studied in some detail.' The other members of the palladium-platinum group of metals have not been studied as extensively, and only qualitative information is available on the vapor pressure of palladium. Data given in literature by Vines1 and Brewer2 on the vapor pressure of palladium are based on the qualitative observations by Holborn and Austin3 and Crookes4 on the rate of volatilization of palladium filaments in various atmospheres. The general observation that palladium is the most volatile metal of the palladium-platinum metal group was corroborated by Bell, Love and Normand who studied the separation of isotopes of the platinum-group metals by a mass spectrometric method. We have measured the vapor pressure of palladium using the Knudsen effusion technique. In this work, the effusion vessel was suspended from a quartz-fiber microbalance into an induction furnace, and the amount of vapor effusing from the vessel was determined by direct weighing of the vessel during the measured heating times. This technique has been described in a report from this laboratory." The vapor pressure of palladium was calculated from these measurements using the equation P...... = 17.14 -W- (77m)'u [1] a t where ? is the weight loss in grams of vapor of molecular weight m from a vessel having an orifice of a sq cm, during t sec. The derivation of this equation from kinetic theory has been described in a previous report from this laboratory: as well as in texts discussing the kinetic theory of gases.%" Test Vessel—In the search for a suitable material for the effusion vessel, it was found that tantalum reacted with palladium metal to form intermetallic compounds, and graphite was readily dissolved in palladium metal to form what appeared to be a liquid phase at a temperature several hundred degrees below the melting point of palladium. On cooling, the graphite gathered into spherical balls in the palladium, with crystals extending radially from the center of these balls, some of which were a millimeter or more in diameter. However, palladium metal vapor did not attack the graphite vessel, so graphite could be used where it did not contact condensed palladium. Tungsten did not appear to react with palladium vapor or molten palladium at its melting point, but it was not convenient to use a tungsten-vapor pressure vessel because of the difficulty of fabricating this metal. Since the vapor-pressure range to be studied (10 2 to 10 ' mm) did not appear to extend above the melting point of palladium, a combination of tungsten and graphite served to provide a very satisfactory effusion vessel. The lower half of the graphite vessel was lined with some strips of tungsten foil and the sample of palladium consisting of a coil of sheet was placed in the tungsten liner; in this way, no contamination of the palladium by carbon occurred. Procedure After outgassing at 1500C, the tungsten-lined graphite effusion vessel was loaded with 300 mg of

Jan 1, 1959

By W. Tempelaar Lietz

The Ten Section oil field is located in the San Joaquin Valley in Kern County, California. about 12 miles southwest of Bakersfield in Township 30 South, Ranges 25 and 26 East. The accumulation is in a low relief anticlinal dome and has a productive area of approximately 2,200 acres. Discovered in 1936 as a result of seismic work, it was the first field on the floor of the Valley to obtain production. It had a small primary gas cap, and since its inception has been produced by depletion with controlled withdrawal from the gas cap to minimize blowthrough. STRUCTURE AND STRATIGRAPHY The Ten Section structure is an elongated anticlinal dome with flank dips of only about 7 degrees. A map of the field, now fully developed, and a composite log are shown in Figs. 1 and 2. Contours shown on the map are on the top of the first zone, or Marker XA as indicated on the composite log. As shown, the field has a productive closure of only some 350 feet, and there apparently is no faulting in the reservoir. The productive measures in Ten Section are of Upper Miocene age and are known as the Stevens sand. They contain thin, irregular shale or siltstone streaks which vary considerably in stratigraphic position and thickness and apparently are rather discontinuous. As a result, individual sands and shales cannot be correlated over any appreciable area, which makes it difficult to subdivide the sand body into separate zones which are distinct throughout the field. However, there are two fairly persistent siltstone bodies that at the time of development were considered to divide the productive measures into three - zones. The first, or uppermost zone is productive over the entire field and has an average thickness of 180 feet, of which some 65 per cent is sand. It had a primary. gas cap in the crestal area with an areal extent of 930 acres. The second zone has a productive area somewhat smaller than the first zone, but it did not have any original gas cap. It has an average thickness of about 360 feet, of which 55 per cent is sand. The third zone has a very limited areal extent and a maximum productive thickness of 100 feet, of which 80 per cent is sand. Recently, a deeper oil accumulation, termed the "53" sand, was discovered, but it is not discussed in this analysis. In the first and second zones the water table was at 7,980 feet subsea, while in the third zone it was at 8,080 feet subsea. RESERVOIR CHARACTERISTICS Sand Characteristics The Stevens sand in Ten Section is hard and well consolidated, and numerous wells were cored for core analysis. Core data on four representative wells are shown, plotted beside the electric logs in Figs. 3 to 6. The average porosity is 20 per cent, with porosities ranging from 15 to 30 per cent. It is estimated, from cores taken with oil base muds, that the interstitial water content is about 40 per cent. The average weighted permeability is approximately 140, with measured permeabilities ranging from 10 to 3,000 md. As might be expected with practically no correlation of individual sand

Jan 1, 1949

By P. R. Swann, R. M. Fisher, W. R. Duff

Observations by transmission electron microscoPy of the microstructures in quenched Fe-A1 alloys provide the basis for revision of the Fe-A1 phase diagram. The diagram is characterized by first-order transitions between the disordered ferromagnetic a! solid solution and the two ordered phases FeAl and Fe3Al. However, second-order transitions showing corre-luted fluctuations in the degree of order near the critical temperature occur between the paramagnetic a! and FeAl and the FeAl and FeAl phases. ELUCIDATION of the true nature of the Fe-A1 equilibrium diagram has proven to be an extremely challenging problem as evidenced by the fact that six quite different versions of the iron-rich portions have been published since 1958.&apos;-6 The most recent diagram shown in Fig. 1 was proposed by Rimlinger6 based on X-ray diffraction analysis and dilatometry. He shows the single-phase fields of the ordered phases of the types FeAl(L20) and Fe3A1(D03) and the disordered bcc Fe-A1 solid solution, a, separated from one another in every case by large two-phase regions. Thus, he implies that in Fe-A1 alloys ordering always occurs via a classical phase transition. In contrast to this view, theoretical studies3&apos;" have concluded that the transitions a — FeAl and FeAl — Fe3A1 should be second- or higher-order in character. A further revision of the Fe-A1 diagram of state is presented in Fig. 2 based on our previous8,9 and current observations by transmission electron microscopy of the microstructures found in quenched specimens. The average quenching rate was 50,000°C per sec and although this was sufficiently rapid to prevent Fe3A1-type ordering below -550°C it was not sufficient to suppress ordering of the type FeAl in the temperature range -650" to 800°C. However, ordering during the quench is easily recognized since the FeAl phase formed during holding at temperature rapidly develops large antiphase domains whereas FeAl formed during quenching has a very fine domain size, -50Å diam. Each symbol in Fig. 2 indicates the result of a micro-structural examination of specimens heat-treated (-1 hr) until equilibrium was established. The results will be discussed in the order of the points, A - Dl marked on both diagrams with reference to the phase fields, critical temperature, and "transition" ranges, respectively. The dark-field micrograph corresponding to point A is shown in Fig. 3 and was obtained using a 111 reflection of the Fe3A1 structure which reveals both a&apos;/4<111> and a&apos;/2<100> antiphase domain boundaries.10 The structure observed in this specimen is typical of single-phase Fe3A1 and shows no evidence for FeAl or any other additional phase. The dark-field micrograph shown in Fig. 4 corresponds to point B on the two diagrams. It was taken with a 100 FeAl reflection which reveals a/2(111) domains and exhibits the typical structure of single-

Jan 1, 1970

By A. H. Duane, A. E. Miller

The high-temperature allotropy of some heavy rare-earth metals and their alloying behavior with magnesium in the 0 to 50 at. pct Mg region was studied by thermal, microscopic, and X-ray methods. Examination of a hcc phase retained upon quenching alloys of different magnesium content confirmed the existence of a bcc high-temperature allotrope in pure gadolinium, terbium, dysprosium, holmium, erbium, thulium, and lutetium. The lattice constants of the pure metals were determined from a Vegard&apos;s Law extrapolation and .found to be 4.05, 4.02, 3.98, 3.96, 3.94, 3.92, and 3.90 + 0.02 A, respectively. In all of the systems studied, the high-temperature bcc phase decomposed eutec-toidally, when slowly cooled, into a hexagonal rare earth-Mg solid solution and a simple-cubic peritec-tic AB-type compound. In 1956, Spedding et al.&apos; observed high-temperature resistivity anomalies in the light rare-earth metals and made several unsuccessful attempts to retain the high-temperature form of these materials at room temperature by quenching the pure metals from temperatures near their melting points. High-temperature X-ray techniques were used by Spedding et a1.&apos; in 1959, to investigate the high-temperature allotropy of the rare-earth metals. This study showed that lanthanum, cerium, praseodymium, neodymium, ytterbium, and possibly gadolinium are bcc at temperatures near their melting points. Discontinuous changes in resistivity at elevated temperatures were also observed for pure gadolinium, terbium, dysprosium, holmium, and lutetium, thus indicating the possible existence of a high-temperature crystalline transformation in these metals. However, due to experimental difficulties encountered in the high-temperature X-ray analysis of these metals, their allotropic form was not identified. Spedding et a~.~ in 1960 observed that yttrium displayed a continuous solid solubility with lanthanum at elevated temperatures, thus showing the high-temperature structure of yttrium to be the same as that of lanthanum, i.e., bcc. Similarly, the high-temperature alloying behavior of gadolinium with yttrium showed gadolinium to be bcc at elevated temperatures. The bcc nature of the high-temperature form of yttrium was again recognized in 1960 by Eash and carlson4 in their study of the alloying behavior of yttrium with thorium. Gibson and Carlson, in a similar study of the alloying behavior of yttrium with magnesium, found that by quenching Y-Mg alloys from within the 0-solid solution region, Fig. l, they were able to retain the allotropic form of yttrium. It was the present authors&apos; intention to use this method to show the existence of a bcc high-temperature form of the heavy rare-earth metals gadolinium, terbium, dysprosium, holmium, erbium, thulium, and lutetium. Simultaneous with the present work, Beaudry and Daane&apos; have shown the bcc nature of the high-temperature form of scandium. EXPERIMENTAL PROCEDURES Materials. The rare-earth metals used in this study were prepared by the calcium reduction of the fluoride and were further purified by vacuum distillation. The magnesium was obtained from the New England Lime Co. and was also purified by distillation prior to its use in the preparation of the rare earth-Mg alloys. The results of chemical and spec-

Jan 1, 1964

MARSHAL Foch has been made an honorary member of the four national American societies of civil, mining and metallurgical, mechanical, and electrical engineers. The governing bodies of these societies, aggregating 45,000 members, conferred this signal honor in expression of the appreciation of American engineers for the unmatched services of this master of engineering principles. At Engineering Societies Building, in New York City, on Tuesday afternoon, Dec. 13, the presidents of the four societies presented one beautifully engrossed certificate of honorary membership in the four societies. The auditorium was filled so that not even standing room was left, more than a half hour before the cere-monies began, and the main entrance on the street had to be closed. J. Vipond Davies, president of the United Engineering Society, made the opening address. Col. William Barclay-Parsons, &apos;who was commander of the first engineer regiment to go abroad, addressed Marshal Foch in French. Colonel Parsons said: The art of engineering was defined a long time ago as "the art of directing the great sources of power in nature for the use and convenience of man." No better definition can be found today. Of all the sources of power in nature, the greatest, the most valuable, and at the same time the most difficult to direct, is the energy of man himself. He who can direct human energy and turn it to the service of mankind is a great engineer. You, Marshal, have directed a greater mass of human energy than any other man has ever done. And you have successfully directed this mass for the highest uses of mankind, in that you by its aid have preserved for him one of the most precious of human possessions-liberty-liberty not only for your own illustrious country, but for all the nations of the world. The four national engineering societies, of the United States now desire to make record of their appreciation of this fact and to convey to you an expression of their most profound admiration for the great leader of men by conferring on you honorary member-ship in all the societies, the highest honor in their gift and one hitherto never conferred on a single individual. Four thousand members of these societies were enrolled in the armed service of the United States, the greater part of whom had the glorious distinction to serve the common cause in France under your orders. They heard the voice and they saw the hand of the master as he led them through battle to victory. Now we desire that you will still continue to lead us, but in peace, by permitting us to inscribe your name at the head of our roll of honor, where it will be, as your deeds have been, an example to us to do better work, and where it will remain forever a noble inspiration for all future generations. Marshal, in the name of those members of the societies who served under your orders and particularly .in the name of those who fell on the field of honor in France, I salute you.

Jan 1, 1922

By N. K. Chen, C. H. Mathewson

Recrystallization of aluminum single crystals after plastic extension is carefully studied in relation to the structure of the deformed matrix. The shapes of the new grains are analyzed with regard to slip planes and to the presence or absence of deformation bands. A mechanism by which the orientations of the grains are related to the parent lattice is described. EXPERIMENTS previously reported&apos; have been extended to develop some of the characteristics of the new crystals which are formed on annealing axially strained crystals whose deformational characteristics had been documented with special care. Thus, the presence of deformation bands affects the growth contours of the crystals, some of the strained crystals produced single crystals anew, and some, polycrystals, on annealing, while others merely "recovered" or "polygonalized" after the 600°C annealing treatment generally adopted in these tests. In the matter of orientational relationships between new crystals and the strained matrix, the present experiments have added little to previous experience, which had demonstrated great variety in the range of orientations encountered and no simple theory or correlation. For example, there has been ample evidence for the predominance in various face-centered cubic metals of a favored orientational relationship; viz., a rotation of 30° to 40° around a <1ll> axis, between grains growing in a matrix with a strong single orientation texture and the matrix itself.&apos;-&apos; This reorientation has been interpreted by various investigators in support of both the "oriented nucleation" and the "oriented growth" hypothesis. In the case of axially extended single crystals of aluminum, no general relationship, such as the one stated above, can be used to correlate the orientations of the recrystallized grains with that of the original crystal. Thus, Carpenter and Elama and Burgers and Basart7 were content to assume that the orientational relationships so developed were random in nature. Mathewson, however, in the Campbell Lecture of 1943 "rgued on the basis of <112> slip that a complex strain, chiefly characterized by rotation around a variable axis in the slip plane combined with a principal rotation around the pole of the slip plane, could be responsible for such devious relationships. Nevertheless, owing to the limited data now available dealing with orientational relationships between new grains and the single crystals strained in tension from which they have recrystallized, no adequate examination of the above generalization could be made. Here, there is the disturbing preliminary condition that any desired orientational relationship may be expressed by means of two rotations about mutually perpendicular axes, so the process lacks a certain critical flavor and any successful choice of axes meeting certain theoretical requirements could be replaced by another differently selected pair. With this reservation clearly in mind the process of double rotations, as previously indicated, was used to relate the orientations of the single crystals which grew out of the strained single crystalline matrix and was construed as certain evidence in favor of the theory of incongruent shearing action proposed by Mathewsons as a necessary element in the (111) slip process with close-packed metals. There is here

Jan 1, 1953

By J. W. Halley

THE effects of tin on steel have become increasingly important because of the necessity of using poorly detinned scrap, tin cans, and terne plate, in the open hearth. Since a tin can contains about 1.5 per cent tin, it would be possible to have up to 0.75 per cent tin in steel made with a 50 per cent scrap charge. In order to use tin-containing scrap, it is necessary to know the effect of tin on various grades of steel. The following investigation is by no means comprehensive but covers a number of steels in which tin content is important. PUBLISHED WORK A number of investigations of the effects of tin on rolling quality and physical properties have been published. It has been found that tin increases strength and hardness and reduces ductility and notched impact resistance. The decrease in ductility and notched impact resistance becomes more marked as the carbon decreases. McKimm1 found no change in Olsen ductility, Rockwell hardness, yield strength, tensile strength or elongation in cold-reduced strip containing up to 0.124 per cent tin. A tin content of 0.15 per cent gave difficulties in rolling and increased the hardness but 0.21 per cent tin showed no change in properties from material containing very little tin. No explanation of this contradiction is offered. Andrew and Peile2 investigated steels containing 0.10 to 0.25 per cent carbon and up to 0.63 per cent tin. They found an increase in tensile strength 0f from 100 t0 200 lb. per sq. in. for each 0.01 per cent tin on normalized samples. The elongation and reduction of area were decreased and the notched impact resistance was reduced markedly. Quenched and drawn samples did not show embrittling if water-quenched from the draw temperature of 1148°F. (620°C.). They could find no evidence of tin under the microscope. Whitely and Braithwaite3 investigated the effect of tin on rail steel containing 0.55 to 0.60 per cent carbon. They found that 0.08 per cent tin caused a marked decrease in elongation, notched impact resistance and the degree of bend. The tensile strength was increased in some tests and not in others. Bolsover and Barraclough4 investigated the effect of tin up to 0.50 per cent on a 0.35 per cent carbon steel and on several alloy steels with from 0.30 to 0.40 per cent carbon. They found a comparatively uniform decrease in notched impact resistance with increasing tin on quenched and drawn samples. If the samples were quenched from the drawing temperature or reheated to the drawing temperature and quenched, the embrittling was much less severe. Steels containing molybdenum suffered much less embrittlement than other steels. EXPERIMENTAL WORK Effect of Tin on Low-carbon Rimmed Steel Increasing quantities of tin were added to four ingots of a heat of the following ladle analysis: carbon, 0.08 per cent; manganese, 0.39; phosphorus, 0.009; sulphur, 0.025.

Jan 1, 1942

By J.W. Halley

The effects of tin on steel have become increasingly important because of the necessity of using poorly detinned scrap, tin cans, and terne plate, in the open hearth. Since a tin can contains about 1.5 per cent tin, it would be possible to have up to 0.75 per cent tin in steel made with a 50 per cent scrap charge. In order to use tin-containing scrap, it is necessary to know the effect of tin on various grades of steel. The following investigation is by no means comprehensive but covers a number of steels in which tin content is important. Published Work A number of investigations of the effects of tin on rolling quality and physical properties have been published. It has been found that tin increases strength and hardness and reduces ductility and notched impact resistance. The decrease&apos; in ductility and notched impact resistance becomes more marked as the carbon decreases. McKimml found no change in Olsen ductility, Kockwell hardness, yield strength, tensile strength or elongation in cold-reduced strip containing up to 0.124 per cent tin. A tin content of 0.1j per cent gave difficulties in rolling and increased the hardness but 0.21 per cent tin showed no change in properties from material containing very little tin. No explanation of this contradiction is offered. Andrew and Peile2 investigated steels containing 0.10 to 0.25 per cent carbon and up to 0.63 per cent tin. They found an increase in tensile strength of from 100 to 200 lb. per sq. in. for each 0.01 per cent tin on normalized samples. The elongation and reduction of area were decreased and the notched impact resistance was reduced markedly. Quenched and drawn samples did not show embrittling if water-quenched from the draw temperature of 1148°F. (620°C.). They could find no evidence of tin under the microscope. Whitely and Braithwaite3 investigated the effect of tin on rail steel containing 0.55 to 0.60 per cent carbon. They found that 0.08 per cent tin caused a marked decrease in elongation, notched impact resistance and the degree of bend. The tensile strength was increased in some tests and not in others. Bolsover and Barraclough4 investigated the effect of tin up to 0. 50 per cent on a 0.35 per cent carbon steel and on several alloy steels with from 0.30 to 0.40 per cent carbon. They found a comparatively uniform decrease in notched impact resistance with increasing tin on quenched and drawn samples. If the samples were quenched from the drawing temperature or reheated to the drawing temperature and quenched, the embrittling was much less severe. Steels containing molybdenum suffered much less embrittlement than other steels. Experimental WoRk Effect of Tin on Low-carbon Rimmed Steel Increasing quantities of tin were added to four ingots of a heat of the following ladle analysis: carbon, 0.08 per cent; manganese, 0.39; phosphorus, 0.009; sulphur, 0.025.

Jan 1, 1943