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By L. E. Snow, L. F. Pett

AT the Utah Copper Pit of Kennecott Copper Corp. a versatile mobile drill unit has been developed and tested. Through increased drilling speed and additional available drilling time, an improvement of 233 pct in drill performance has been realized. Operators using drill power can quickly and easily convert the unit from a vertical to a toe hole drill. Drilling is done with the machine in line with the unit or at right angles to it. Table I covers the 1950 drill record at the mine, showing the types of machines used and the footage obtained. Development of the new units was prompted by a desire for solution of the following problems: 1—The ever-expanding operations within the Utah Pit, requiring some 65 miles of transmission pipe lines radiating from a central compressed air plant, have now taxed this compressor plant beyond capacity. While 100 lb per sq in. pressure is maintained at compressors, transmission losses from innumerable small leaks result in low terminal pressure at the drills. Fig. 1 illustrates that while terminal pressure varies according to size of air hose and fittings used, the average drill is operating on air pressures within the 60 to 70-lb range. The compressor plant is operated primarily for air rock drills. All drilling is done on day shift, but it is necessary to run two of the three 3720 cu ft capacity compressors during night shift in order to prevent drastic loss of pressure through leaks. On day shift all three compressor units are operated at capacity, so that there is no reserve safeguard available for extensive repairs to any compressor. The calculated volume of compressed air required for operation of 25 drills is but 33 pct of three day-shift compressors. While compressed air is being used to a minor extent for purposes other than drilling, it is felt that satisfactory substitute facilities could be pro- vided in the event that air lines were no longer available. 2—Drill performance has increased beyond the capacity of present 3-in. drifter machines. 3—The installation, maintenance, and moving of air lines in routine mining is a growing problem. The 2-in. level lines are placed outside electrification towers and must be moved to new location upon completion of each shovel cut. In addition to these moves it is often necessary to dismantle level lines so that excessive shovel spillage, or material covering track following a blast, can be pushed in the clear with bulldozers. Where level room is limited, it is often necessary to remove air lines in giving bulldozers room to prepare grades for wagon drills. In spite of precautions taken, many level lines become buried, twisted, and constricted, with excessive air loss resulting. Excessive back break in blasting often leaves several sections of air line suspended in mid-air. Occasionally air lines come in contact with defective electric transmission towers, so that holes are burned through pipe. 4—Rail-handling of drilling equipment such as wagon drills from one location to another requires considerable locomotive crane crew time. Any new unit developed should travel under its own power. 5—Present practice requires accessory material including hose, water pressure tanks, water barrels, drill steel, and bits to be transported by means of push cars when drill locations are changed on any level. 6—In order to supply numerous drill locations with material, many stock piles of new drill rods, drill bits, and other essentials must be left at strategic points, usually in the vicinity of powder magazines. This practice makes for poor housekeeping and contributes to the loss of supplies. Planning the Unit It was felt that a mobile drill unit which would rectify the foregoing problems should meet certain demands: 1—It must furnish compressed air to operate a 4-in. rock drill at a pressure of 90 to 100 lb.

Jan 1, 1953

By F. D. Rosi

IN the production of single crystals by the Bridg-man method of solidification from the melt in vacuum at a crucible lowering rate of 0.25 in. per hr, a cellular structure was frequently observed in copper and copper-base alloys at the terminal surface of the as-cast crystals (i.e., the surface representing the last portion of the crystal to solidify). The geometrical form of this structure varied from crystal to crystal, but, in general, could be classified as either hexagonal or quadrilateral. Fig. 1 shows examples of this cellular structure, which is similar to that reported by Buergerl and, more recently, by Pond and Kessler&apos; and Rutter and Chalmers. In the micrographs of Figs. lb and c, the cubic structure in the alloy crystals is obscured somewhat by excessive surface evaporation in the final stages of solidification. X-ray orientation studies indicate that the traces outlining the various geometrical forms correspond to octahedral planes, which are the planes of greatest reticular density in the face-centered cubic lattice. It would appear from this that the view first propounded by Bravais,4 that the surface energies and normal growth velocities of the different crystal planes are inversely proportional to their reticular densities, applies to this cellular structure, since those surviving are the planes of greatest atomic density. Thus, the observed variation in the geometrical form of this structure in crystals of different orientation is readily understandable from the distribution of the (111) planes in the standard {111}, (1101, and (1001 stereographic projections. Depending upon whether the crystal axis (i.e., the direction of crystallization) coincides with a <111>, <111>, or <100> direction, the cellular structure viewed from a surface perpendicular to the crystal axis will consist of a network of regular hexagons, skewed hexagons (with interfacial angles of 110" and 125"), or cubes, respectively. It follows, moreover, that off-orientations from these principal directions will yield modifications of these three basic geometric configurations. In this connection, it is interesting to note that the bounding planes of the hexagonal structure observed in tin by Rutter and Chalmers3 showed no preferred orientation.

Jan 1, 1954

By Robert S. Dewey

More wells were drilled in West Texas† during 1944 than in any year since 1941. As compared with 1943, there was an 82.5 per cent increase in the total number of completed wells. The 1646 wells required an estimated 140,715 days to complete for a total of 7,632,249 ft. An average of 85 completion days was required to drill to an average of 4630 ft. This depth is approximately 100 ft. greater than that of the previous year. It is estimated that $100,000,000 was invested in drilled wells. As of Dec. 31, 1944, there were 270 field and 91 wildcat wells being drilled. While an identical number of wells were drilling Dec. 31, 1943, the proportion of wildcats increased in 1944 from 19.7 to 25.2 per cent. During 1944, oil wells were completed in 103 of the 164 fields in West Texas. Of the 1361 oil wells, 385 were in Slaughter, 116 in Fullerton, 63 in North Cowden, 62 in Fuhrman-Mascho, 59 in Wasson, 52 in Westbrook and 47 in North Ward. Approximately 22 per cent of the wildcat drilling was to pre-Permian formations. Despite the increasing proportion of wildcat wells drilled, the wildcat discovery rate has declined since the year 1942. AS compared with 1943, the number of wildcat wells drilled increased from 11.7 to 12.7 per cent and the footage in wildcat exploration increased from 13.3 to 13.8 per cent of the total. The monthly production of crude continued to increase to a peak of 15,336,000 bbl. in October 1944. As compared with a similar peak production in October 1943, there was a 37.3 per cent increase. The yearly production increased from 98,165,-ooo bbl. in 1943 to 159,943,000 bbl. in 1944, an increase of 62.8 per cent. Based upon an assumed average price of $1.00 per barrel and less 1/8 royalty, the gross return to the producer amounts to $140, 000,000. From 1943 to 1944, the average number of producing wells increased 6 per cent while the average daily production per well increased 53.1 per cent. The average daily production per well increased from 17.5 bbl. in 1943 to 26.8 bbl. in 1944. The proportion of flowing wells decreased from 50.5 per cent in January to 49.1 per cent in December 1944. Drilling With the continued shortage of labor and materials, drilling costs have risen sharply. Just how much is difficult to ascertain. Owing to competition for available drilling rigs, contractors are reluctant to assume drilling risks. In consequence, some contracts are let on a cost plus basis, or day work below some specified depth with the operator furnishing part of the consumable materials, such as mud and drilling bits. Contractors are having difficulty in maintaining full and effective drilling crews with insufficient and inexperienced labor. Service companies have inadequate labor and equipment to meet their appointments promptly. Pipe Lines The Gulf Pipe Line Co. increased the capacity of its 10-in. main line by filling in gaps amounting to 75 miles on the loops between Judkins and Weatherford, Texas.

Jan 1, 1945

By H. A. Koch, R. L. Slobod

This paper discusses a new oil recovery process called the "miscible slug process." This process involves the injection of propane or LPG into the reservoir prior to gas injection. The operating conditions are maintained so that the slug is miscible with both the reservoir oil and the injected gas phase. Thus, a miscible phase displacement is achieved, and high recoveries are obtained from the area of the reservoir contacted. The most striking discovery of the laboratory study which included displacements from cores up to 123 ft in length was that relatively small slugs of LPG are effective over reservoir distances in the miscible displacement of oil. This makes possible the commercial application of the process. The important factors controlling the size of the slug are: (I) reservoir length, (2) reservoir fluid composition, and (3) reservoir pressure at the displacement front. Of lesser importance are the effects of injection rate and porous medium type. Questions which have not been completely answered deal with the effects of gravity and reservoir inhomogeneities on the process. INTRODUCTION One of the major problems facing the oil industry today is recovery of the large fraction of the discovered oil which will remain unrecovered unless some new processes are found. Water flooding has been one successful method used to increase recovery over natural depletion. But even successful water floods may leave 25 to 40 per cent of the pore space filled with residual oil. Recently a process which involves the use of thermal energy has been reported1,&apos;*&apos; which may prove useful in increasing recovery from shallow reservoirs containing highly viscous crudes. This paper deals with a new oil recovery process involving use of miscible phases to displace the oil from the reservoir. Miscible phase displacement oil has been an intriguing idea because the elimination of capillary effects in the reservoir leads to 100 per cent recovery in the areas contacted by the miscible displacing phase. The big deterrent in the past to the practice of miscible phase displacement has been the high cost involved in using large volumes of solvent in the process. The use of high pressure gas to achieve a miscible phase displacement of reservoir oil has been reported4,5 as one economically feasible method. However, this process calls for the maintenance of pressures above 3,000 psi at the dis-placement front. The process described in this paper is not restricted to high reservoir pressures; the only qualification being that the slug of material which is injected into the reservoir must be miscible with both the displaced oil 2nd the displacing phase. Two such cases are the use of an alcohol slug followed by water to achieve a mis-cable water flood, and the use of a low boiling hydrocarbon slug such as propane followed by gas to achieve a miscible gas drive. This paper will deal specifically with the propane dug process. This process will obtain a miscible phase displacement at pressures as low as about 1,200 psi at a reservoir temperature 01 150°F. The process is very simple. The propane displaces oil completely at one front because it is miscible with the oil, and gas displaces the propane completely at a second or trailing front because it is miscible with the propane. A small band of propane should thus remain wedged between the gas and oil phases. This idea has been called the "miscible slug process."6 Unfortunately, the propane slug will become diluted as it flows through the reservoir. This results from a mixing action since the fluids flow through a complex reservoir porous medium rather than simple capillaries. Fig. 1 diagrams a miscible slug displacement. The effects of some of

Jan 1, 1958

By R. Taggart, R. H. Ericksen, D. H. Polonis

Transmission electron microscopy techniques hare been used to study the spontaneous marfensite phase that forms during the thinning of Ti-Cr alloys. The structure of this phase has been found to differ. from the hcp martensite and has been identified as a clisforted fcc lattice. The spordaneous marlensile in this system is interpreted as a metastable isomorph of the equilibriunz TiCr, phase. WHEN thin-foil specimens for transmission electron microscopy were prepared from metastable alloys of the Ti-Cr system, a spontaneous transformation occurred&apos; when the foils contained the untrans-formed 0 phase or two-phase mixtures of the 0 and w phases. The purpose of this paper is to examine the relationship that exists between the crystal structure of the spontaneous product and that of the matrix. The differences between the martensite transformation that occurs in the bulk material and the spontaneous reaction that occurs during the preparation of thin foils are compared with the observations that have been reported for similar phenomena in a commercial titanium alloy.&apos; A spontaneous reaction that exhibits characteristics similar to a martensite transformation has been reported to occur in thin foils prepared from the retained metastable structures of several alloy systems.1&apos;3"7 ~ull~ observed such a spontaneous reaction in 0 brass and attributed the apparent increase in the martensite transformation temperature to a decrease in the non-chemical free energy associated with bulk strain energy. He also showed that the spontaneous product did not have a specific habit plane, but that its orientation relationships to the parent matrix were dependen on the thickness of the transforming region. It has also been pointed out by Breedis6 that in thin films the absence of the constraints imposed by a bulk matrix can cause different requirements for the martensite plate interface and lattice distortion which is reflected bv a dependence of the transformation mechanism on the specimen geometry. In the case of the spontaneous reaction reported for Au-Zn alloys7 a definite habit plane was determined and shown to correspond with the habit plane calculated on the basis of the Bowles and Mackenzie crystallographic theory of the martensite transformation.&apos;- lo EXPERIMENTAL PROCEDURE A series of titanium alloys containing 5.5, 5.9, 6.4: 7.6, 8.0, 11.3, and 18.7 at. pct Cr were prepared from high-purity (iochrome) chromium and iodide-grade titanium by levitation melting. The experimental procedure used for sectioning the alloys and for thin-foil preparation has been reported in an earlier paper.&apos; X-ray diffraction patterns were obtained using a 114-mm Debye-Scherrer camera and Cu-Ka radiation. In order to minimize fluorescent radiation from the specimen, a strip of aluminum foil 0.002 in. thick was placed in contact with the X-ray film. After a specimen was removed from the camera: an additional X-ray experiment was performed, to insure that no spurious lines were obtained due to the presence of the aluminum foil. The interstitial impurity analysis for the alloys used in this study was as follows: oxygen, 100 ppm: hydrogen, 30 ppm: nitrogen, 28 ppm. EXPERIMENTAL RESULTS Electron diffraction patterns were obtained from several individual crystals of the spontaneous marten-

Jan 1, 1970

By I. L. Dillamore

A purely geomentrical analysis based on oriented-growth relationships is presented to derive annealing-texture orientations in bcc metals from their- known deformation textures. The analysis takes as its starting point a description of- the bcc deformation texture and follows previous work on fcc metals in considering pvobable nurleation sites for recrystallization and the textural limitations on grains growing into a deformed matrix. The analy-sis accounts for the prominent and the minor coinponents of the annealing textures formed from two the deformation textures and can account for the ob-sem:ed temperature dependence of the annealing texture of bcc metals. THERE have been a number of investigations of annealing textures in bcc metals but few attempts to relate these textures to the deformation textures. This has been largely due to the lack of definition of both annealing and deformation textures, neither of which shows sharply defined orientations. It is, however, necessary to get a better understanding of primary recrystallization textures in bcc metals in view of increasingly exacting demands upon the quality of steel sheet for drawing purposes and as a necessary step towards the control of textures through processing. An analysis is presented here which relates annealing textures to deformation texture, by a purely geometrical method. This takes as its basis the oriented-growth theory of recrystallization and makes some reasonable assumptions regarding the make-up of bcc deformation textures and the limitations on growth relationships in bcc metals. Detailed information on this latter point is not available at the present time, and the present analysis may need to be streamlined or extended when such information is at hand. It is felt, however, that despite these limitations the analysis provides useful results and a valuable aid towards understanding the effect of processing variables. 1) BCC ROLLING TEXTURES Different workers have used a variety of descriptions for the texture developed in bcc metals by rolling. For the present purpose it will be assumed that two different deformation textures can be obtained: 1) a texture containing a major (112)[li0] component and a minor (001)[1i0] component for which increasing deformation causes the (001)[li0] component to increase at the expense of the (112)[li0] component, as suggested by Dillamore and ~oberts&apos; (this is the texture predicted to arise starting from randomly oriented material); 2) a t~xture containing the above components and (111)[110] and (ii1)[112] components. This texture could arise from a material with an initial (110)[001] or (iil)[112] texture. It is well-known that the (ll0)[001] orientation rotates to (ii1)[112]that on roll-

Jan 1, 1965

By Cleveland Dodge

THE present organization of Copper Queen employ-ees, known as the Employees&apos; Conference Com-mittee, is really an outgrowth of the former Grievance Committee, which, in turn, had developed from the original Hospital Committee. The relatively small membership of these older organizations, the practical limitation of their activities to the presenting of grievances, and their lack of initiating powers, were the principal defects which the plan now in operation seeks to overcome. A somewhat parallel scheme was instituted in our Sacramento Hill division about four years ago; this gradually developed into the Ways and Means Committee, which, in addition to providing a forum for the discussion of operating problems, was instrumental in establishing an excellent and mutually satisfactory bonus system. Before recommending adoption of the plan now in force, we made extensive inquiries among those who have had any experience in such matters, and ended by proposing a modification of a scheme developed by John Leitch,1 which was characterized by its similarity to the constitution of the Federal Government. As finally remodeled, the. plan was submitted to vote of the entire working forces at the Copper Queen mines, and was adopted by them in May, 1920. Mining opera-tions since that date have been so interrupted that it is scarcely possible to state exactly what the results have been. The following quotations are from a printed pamphlet containing the constitution of the organization, as finally adopted. The first extract is from a letter addressed by the management to the employees: The plan submitted for your approval and adoption is modeled after the constitution of our own country, under which every individual is given an opportunity for advancement, according to his ability and determination, and every citizen is given a voice in the laws that shall govern him. So it is to encourage the individual employee in advancement, and to give him a voice in making the rules that shall govern his conduct, that we favor the adoption of the proposed constitution.

Jan 1, 1923

By Arthur Glance

MINE safety is of the utmost importance to all operators and most operations have a safety organization, or safety inspector, whose job it is to be continually on the alert to detect and correct the hazards of mine operation. Reports from the Bureau of Mines show that next to roof falls, gas presents the greatest hazard in mining. The Bureau of Mines Information Circular 6680 shows that 162 explosions occurred in the United States during the five-year period ending June 30, 1932. Deaths resulting from these explosions amounted to 984, with a great many disabled and disfigured. A fatality rate of 6.07 persons shows the ex¬treme severity of this hazard to the industry. Various mine appliance companies have put on the market instruments for methane detection, which record in direct percentages the amount of methane present in the atmosphere. Unfortunately, few mining companies are using these instruments, however. Those available include the Burrell methane detector, the Wolf, the Martienssen, the Mine Safety Appliance detector, and the Union Carbide Company methane detector, which last I have used extensively in making mine inspections.

Jan 1, 1936

By W. D. Robertson

The effect of a tensile stress in accelerating the corrosion-cracking of certain alloys of aluminum, magnesium and iron is widely recognized. The literature is extensive and it is only necessary to cite the recent ASTM—AIME Symposium,l There are, however, no experimental data conclusively showing the effect of an applied compres-sive stress. It has been inferred, from the generally accepted mechanism postulated for the acceleration of corrosion by an applied tensile stress, that a compressive stress would inhibit corrosion. Furthermore, it is observed that corrosion cracks invariably start on the tension side of a specimen bent as a simple beam. This observation has led to the suggestion that shot-peening of the surface would inhibit or eliminate stress-corrosion cracking in magnesium alloys and aluminum alloys. However, the degree of inhibition produced by shot-peening does not appear in the literature except for the above qualitative references which are unsupported by experimental data. Moreover, while peening undoubtedly imposes a surface compressive stress, the alteration of the surface by the severe cold-working involved complicates the interpretation of the results with respect to the effect of a compressive stress alone. If corrosion proceeds along preferential paths produced by precipitation from solid solution, it is easily understood how a component of tensile stress normal to these paths will accelerate the corrosion and lead to ultimate failure. On the other hand, if the metallurgical conditions are such as to create preferential corrosion paths, then it is difficult to understand how a compressive Stress, produced by shot-~eening Or any other method, can inhibit corrosion except in the sense that the accelerating factor is removed. Thus, if the basic corrosion mechanism remains unaltered, there should be little or no inhibition resulting from the application of a compressive stress if inhibition is defined as the reduction of the degree of corrosion below that experienced in the unstressed state. The experiment described below was performed to isolate and evaluate the effect of a compressive stress on the corrosion and stress-corrosion cracking of a high strength aluminum alloy (24-S); and, by a Comparison of the corrosion rate of &apos;pecimens subjected to an applied tensile stress, compressive stress and in the unstressed state, to clarify the role of stress in intergranular corrosion. Experimental Procedure The experiment was conducted with the aluminum-copper-magnesium alloy known as Duralumin 24-S.* Specimens, 0.064-in. thick, in the form of I-in. wide strips sheared parallel to the rolling direction,

Jan 1, 1949

By N. H. MacMillan, O. C. Dias

Recent work by Westwood et al. (reviewed in Refs. 1-6) has established that many rocks, minerals, ceramics, and glasses exhibit phenomenologically similar chemomechanical (Rebinder) effects when deformed in different liquid environments, apparently as the result of chemisorption-induced variations in their near-surface flow and flow-dependent fracture behavior. In particular, it appears that there exists an empirical, but apparently general, correlation between the near-surface flow stress of an inorganic nonmetal and its surface charge- namely, that such a solid is hardest at its zero point of charge (i.e., when its zeta potential [ ] = 0) and softens as [ ] increases, regardless of the sign of zeta. Moreover, because near-surface flow and fracture phenomena are two of the important determinants of the rates of machining and comminution processes, both Westwood et al. and others7 have been able to use this so-called "[ ]-correlation" to develop cutting fluids and grinding aids that in many instances have given rise to several fold increases in performance. In addition, Westwood et al. have demonstrated that both aqueous and organic environments can give rise to similar improvements in cutting rate for a given combination of tool and workpiece, provided that both impart the same surface charge to the work- piece (i.e., transfer the same number of electrons to or from its surface). This last finding implies that in any application it should always be possible to find some cutting fluid that is at once effective, cheap, nontoxic, and nonpolluting. Thus, reports of apparently similar environmental influences on the mechanical behavior of diamond,8 certain organic crystals and polymers,9-14 and coa1-15-21 suggest that it is pertinent to ask: (a) whether the [ ]-correlation (or any analogous relationship) extends to coal; and (b), if so, whether this relationship can be used to guide the development of superior aids for grinding coal. Accordingly, correlations have been sought between (1) the zeta potentials, (2) the hardnesses, and (3 and 4) the drilling and grinding characteristics of coals of different rank in different aqueous and organic environments. This paper reports the results of that search.

Jan 1, 1980

By H. M. Manasevit, R. L. Nolder, L. A. Moudy

The observation that silicon-on-sapphire crystallo-graphic relationships exist which are unrelated to one another implies that there are regions of sapphire orientations containing these relationships which are separated by boundaries. The presence of these boundaries is demonstrated, initially on rounded cylindrical surfaces md more definitively on flat sapphire substrates with orientations along primary crystallograPhic zones. By means of reflection electron and X-ray diffraction techniques the crystallographic relationships have been studied. Two new relationships have been found, viz., (111) Si (1014) sapphire and (001)Si (1012) sapphire. Also found were multicrystalline relationships. The approximated boundaries between the crystallographic regions for each relationship are shown by means of a stereo-graphic projection. These studies also clarify discrepancies in the literature concerning the silicon-sapphire relationships on the (1120) sapphire substrate. SINCE the first report of the deposition of single-crystal silicon on sapphire in 1963&apos; this epitaxial system has been the object of study by many semiconductor laboratories. In particular, there has been strong interest in the crystallographic relationships between the two materials. In 19652,3 we demonstrated that at least four distinct modes of orientation relationships can occur, namely, (100)Si (0112) sapphire, (111)Si 11 (1124) sapphire, (111)Si (1120) sapphire, and (111)Si (0001) sapphire. Each relationship could be obtained when the substrate plane was at the particular orientation indicated. Other workers as well as our laboratory concurred in general with the initial results. However, two discrepancies were observed. First it was observed by Joyce et a1.4 that on a (1120) substrate a (110) silicon deposit could be obtained. This was actually consistent with the (111)Si (1124) sapphire mode. Second, two other laboratories,5,6 as well as our own,7 have found a deposition on the basal plane which is different than our initial findings. Even though a (111)Si deposit was obtained, the crystallographic relationships were not identical to those previously found. Subsequent work in our laboratories has confirmed that the form found in these later investigations of the basal plane is by far the more predominant, and the original finding was an anomaly. The relationships which have been previously estab1.ished are summarized in Table I. It is seen that at present a rather small number of possible substrate orientations has been investigated. Therefore, it seemed appropriate that a systematic investigation of silicon epitaxy on various sapphire substrate orientations would be of value. It was expected that the answers to three questions could be obtained from such an investigation. These are as follows: 1) Since we know of at least four distinct modes of orientation relationships, over what range of substrate orientation do these modes occur and what is the form of the boundary expected between the different regions in which each mode occurs? 2) Are there other modes which occur on substrate orientations not previously investigated? 3) What is the explanation for the discrepancy between our laboratory&apos;s findings and those results reported by Joyce et al.4 concerning the relationships occurring on (1120) substrates? APPROACHES AND EXPERIMENTAL METHODS Two different approaches were used. Initially, depositions were carried out on rounded cylindrical surfaces which lay perpendicular to the (0112) plane.* By this means the presence of boundaries and their approximate positions could be determined. Finally and more definitively, depositions on flat sapphire substrates with a variety of orientations, mostly along primary crystallographic zones and about the (1120) plane, were studied by means of reflection electron diffraction and X-ray diffraction (using back-reflection Laue patterns and full circle goniometer techniques) in order to determine crystallographic relationships. The sapphire orientations investigated by these means

Jan 1, 1969

By L. E. Snow, L. F. Pett

AT the Utah Copper Pit of Kennecott Copper Corp. a versatile mobile drill unit has been developed and tested. Through increased drilling speed and additional available drilling time, an improvement of 233 pct in drill performance has been realized. Operators using drill power can quickly and easily convert the unit from a vertical to a toe hole drill. Drilling is done with the machine in line with the unit or at right angles to it. Table I covers the 1950 drill record at the mine, showing the types of machines used and the footage obtained. [ ] Development of the new units was prompted by a desire for solution of the following problems: 1-The ever-expanding operations within the Utah Pit, requiring some 65 miles of transmission pipe lines radiating from a central compressed air plant, have now taxed this compressor plant beyond capacity. While 100 lb per sq in. pressure is maintained at compressors, transmission losses from innumerable small leaks result in low terminal pressure at the drills. Fig. 1 illustrates that while terminal pressure varies according to size of air hose and fittings used, the average drill is operating on air pressures within the 60 to 70-lb range. The compressor plant is operated primarily for air rock drills. All drilling is done on day shift, but it is necessary to run two of the three 3720 cu ft capacity compressors during night shift in order to prevent drastic loss of pressure through leaks. On day shift all three compressor units are operated at capacity, so that there is no reserve safeguard available for extensive repairs to any compressor. The calculated volume of compressed air required for operation of 25 drills is but 33 pet of three day-shift compressors. While compressed air is being used to a minor extent for purposes other than drilling, it is felt that satisfactory substitute facilities could be provided in the event that air lines were no longer available. 2-Drill performance has increased beyond the capacity of present 3 ½ -in. drifter machines. 3-The installation, maintenance, and moving of air lines in routine mining is a growing problem. The 2-in. level lines are placed outside electrification towers and must be moved to new location upon completion of each shovel cut. In addition to these moves it is often necessary to dismantle level lines so that excessive shovel spillage, or material covering track following a blast, can be pushed in the clear with bulldozers. Where level room is limited, it is often necessary to remove air lines in giving bulldozers room to prepare grades for wagon drills. In spite of precautions taken, many level lines become buried, twisted, and constricted, with excessive air loss resulting. Excessive back break in blasting often leaves several sections of air line suspended in mid-air. Occasionally air lines come in contact with defective electric transmission towers, so that holes are burned through pipe. 4-Rail-handling of drilling equipment such as wagon drills from one location to another requires considerable locomotive crane crew time. Any new unit developed should travel under its own power. 5-Present practice requires accessory material including hose, water pressure tanks, water barrels, drill steel, and bits to be transported by means of push cars when drill locations are changed on any level. 6-In order to supply numerous drill locations with material, many stock piles of new drill rods, drill bits, and other essentials must be left at strategic points, usually in the vicinity of powder magazines. This practice makes for poor housekeeping and contributes to the loss of supplies. Planning the Unit It was felt that a mobile drill unit which would rectify the foregoing problems should meet certain demands: 1-It must furnish compressed air to operate a 4-in. rock drill at a pressure of 90 to 100 lb.

Jan 1, 1952

By R. W. Newcomb

THE constancy of calibration, and to a great extent the life, of a thermoelement is dependent on the suitability of the primary protecting tube in which the wires are mounted, particularly when used at high temperatures. An ideal thermocouple protecting tube would be com-posed of materials that would not contaminate the thermoelement wires contained in it-one that would remain absolutely gas-tight ,it all temperatures of usage, that will not be attacked by gases, or other surrounding agencies, that is not destroyed by heat, that withstands sudden and extreme temperature changes, that affords a high degree of mechanical protection and does not deform at high temperatures, that is a good heat conductor and obtainable in small diameters so as to keep down lag factors. It has not yet been possible to produce tubes of any known mate-rials that will meet all of these conditions. In selecting protecting tubes, therefore, one should be chosen the characteristics of which best fit it to the particular conditions of usage. Frequently conditions are such that two tubes have to be used, a primary gas-tight protecting tube inside of a secondary protecting tube, because certain agencies will attack the primary gas-tight tube unless it is guarded by the outside tube.

Jan 9, 1919

L. C. Graton, Cambridge, Mass.—The subject of chalcocite occur; rence and its geological significance has, of course, a very important commercial bearing, as shown by the recent remark of a hard-headed mining .man: "This secondary enrichment business is one thing you geologists have put up which we can hang on to, and come out right." Most enrichments of copper ores depend upon the formation Of chalcocite from leaner sulphides. Recently it has been shown that not only does there exist this secondary or derived chalcocite, * but that in certain ores the mineral is present as an initial or original constituent, which therefore we may call primary. The desirability of distinguishing between these two kinds of chalcocite is evident and has recently been emphasized. That constitutes the first problem in this connection. I believe many who are working upon secondary enrichment of mineral deposits are giving much attention to that particular question. It is now possible to distinguish primary from secondary chalcocite in many cases. In such cases, what do we know of the&apos; conditions under which this secondary or derived chalcocite was formed? , This is the second main question in connection with the subject. It is now plain, at least in many instances, that the formation of this derived chalcocite represents a phase of oxidation if we have in mind the primary ore as the thing acted upon. The next important question—and it is most important—is: does such oxidation go on above the zone where the rocks are saturated with water—that is, above the water level—or below, or indiscriminately above and below? Many of you have, or have had, opportunities to study at first hand, day after day, occurrences that&apos; enable valuable conclusions to be drawn upon these and other important questions concerning the formation and significance of chalcocite. It is greatly to be hoped that your testimony will be made available and undoubtedly it will go far toward clearing up some of these doubtful points. John D. Irving, New Haven, Conn.—A short time before this meeting was called, H. V. Winchell, who was unable to be present, requested me to exhibit and describe these two samples of pyrite. (Exhibiting specimens.) They consist of fragments of pyrite inclosed in two small bottles. The first bottle shows fragments of pyrite which were immersed in water carrying copper sulphate but without SO2 for a period of two years. They remained comparatively clear and bright. No chalcocite has been deposited on them. The second bottle shows fragments of

Jan 1, 1915

By C. A. Rowland, R. C. Nealey

Until recently there were very few dry grinding rod mills used. The early installations performed as anticipated. In the last seven years a number of dry grinding rod mills have been made, most of which have been used for grinding iron ore. The recent installations have not operated as anticipated in accordance with practices learned from wet rod milling. The paper does not establish any definite rules for the application of dry grinding rod mills but does attempt to establish some guidelines that can be followed. The paper reviews a number of flowsheets describing the problems encountered and some of the solutions found. Completely dried compared to partially dried feed is reviewed. Problems encountered in scaling up from pilot plant to production-size mills are described. Rod sizing, effect of rod length, rod bending, rod breakage, and rod tangling are discussed. While wet grinding rod mills have been used for 50 years to grind ores and make specifications sands, dry grinding rod mills have only recently come into significant use in the mineral industries. Among the materials now being processed in dry grinding rod mills are (1) lead sinter, lead slag, and limestone; (2) iron ore; (3) silica; (4) cement clinker; and (5) coke. Because the application of wet grinding rod mills was well understood at the time that dry grinding rod mills were introduced, the criteria and guidelines for selecting the former were carried over to the selection of the latter - in some cases with the anticipated results, but in many cases not. It is the purpose of this paper to describe, through a series of flowsheets, some of the recent problems encountered with dry grinding rod mills, to point out the solutions to these problems, and to set forth some guidelines for the selection and application of these mills. When dry grinding rod mills came into use, the following facts about their wet grinding counterparts were already well established: (1) The performance of large-sized mills can be accurately predicted from the performance of rod mills 5 or 6 ft in diameter. Wet grinding mills as large as 14 ft in diameter (inside shell) by 20 ft long with rods 19.5 ft long can operate satisfactorily.

Jan 1, 1970

By William R. Patterson

ACCORDING to the phase diagram for the Mn-Ni system,&apos; the high-temperature, fcc y-manganese solid solution is stabilized to below room temperature, in the range approximately 22 to 28 wt pct Ni. However, pearson2 cites evidence in the literature showing that for manganese contents greater than about 75 wt pct the quenched phase in Mn-Ni alloys is fct. This is in keeping with zener&apos;s3 suggestion that in manganese-rich alloys the fcc high-temperature phase undergoes a diffusionless or martensitic transformation to a fct structure upon quenching. Work by Basinski and christian4 on manganese-rich compositions in the similar alloy system Mn-Cu established that in alloys of greater than about 82 wt pct Mn the y-manganese phase underwent a fee fct martensitic transformation upon quenching to room temperature. Striking evidence for this martensitic transformation was the highly twinned or banded microstructure, an example of which is shown in Fig. 1. Similar microstructures have also been found in quenched Mn-Cr5 and Mn-Au6 alloys. In the present investigation, we attempted to obtain similar evidence of a fcc — fct martensitic transformation in manganese-rich Mn-Ni alloys. Manganese alloys in the range 10 to 30 wt pct Ni were prepared by arc-melting, under argon, at atmospheric pressure. The alloys all were 50 g in size, and negligible weight loss occurred during melting. The starting materials were electrolytic manganese and nickel, both of 99.9+ pct purity. The alloys were subsequently homogenized 48 hr at 1750°F, hot-rolled 50 pct at 1700°F, annealed 2 hr at 1700°F, and water-quenched to room temperature. All heat treatment was done in purified argon. Both X-ray and metallographic techniques were used to examine the structures of the quenched alloys. X-ray diffractometer studies were conducted on powder specimens obtained from filings rean-nealed 2 hr at 1700°F in argon and water-quenched. Identification of the intensity peaks from the diffractometer counter traces showed that below about 10 to 12 pct Ni the y phase decomposed partially upon quenching to give an a- + ?-manganese structure. In the range approximately 12 to 25 pct Ni, the structure was found to be fct ? manganese with a c/a ratio approaching 1.0 at 25 pct Ni. Beyond approximately 25 pct Ni, the structure remained fcc. These results, including lattice-parameter determinations, are given in Table I. Metallographic examination. was carried out on specimens polished and etched after quenching, and also on polished specimens reannealed and quenched. In the first case, the distinctive twinning or banding so prevalent in Mn-Cu alloys was sought, while in the second, the surface relief effect generally regarded as being truly characteristic of a martensitic transformation was sought. The microstructure of representative alloys in the range 12 to 25 pct Ni is shown in Fig. 2. The structure of the Mn-15 pct Ni

Jan 1, 1965

By Leendert de Witte

A review is given of the principles on which recently proposed methods of electric log interpretation in shaly sands are based and of the evidence brought up in support of the theoretical derivations. It is. pointed out that the qualitative techniques suggested to date have a tendency to be too pessimistic in the prediction of the presence of commercial hydrocarbon accumulations. In the quantitative treatment, a new concept is introduced, namely that of strongly reduced activity of the double layer counter ions which are present near the negatively charged rock surfaces. This lemmu when applied to the calculation of the equilibrium concentratiotls of interstitial waters yields a set of very simple relations. The resulting expressions for electrochemical potentials across rock samples appear in satisfactory agreement with laboratory experiments. The formulae obtained for the electrical conductivity of shaly formatioris are of the same form as those arrived at empirirally by previous workers. Combination of the expres.riorls for potentia1s and conductivities gives a direct proof of the Tixier relation which states that for shaly water sands the product of apparent formation water resistivity and apparent formation factor equals the resistivity of the sand 100 per cent .saturated with formalion water and which was verified by the work of Wyllie and Perkins and their co-workers. The relations for the resistivities and spontaneous porer11inI.s have been extended to the case of hydrocarbon hearing shaly formations, thus laying a formal basis for the quantitative interpretation of electric logs in shaly oil sands. INTRODUCTION The presence of disseminated clays in porous rocks saturated with electrolytic solutions has a strong influence on the transference of ions taking place under electrical or chemical potential gradients. Both the electrochemical emf&apos;s in evidence on the SP curves of electric logs and the electrical conductivity measured on resistivity logs arc directly dependent on the ionic transference in the interstitial waters of the formations traversed by boreholes. A large number of researches have been carried out on the nature and magnitude of the effects of clays on ionic transference. The most recent of these have been described in papers by McCardell and Winsauer,1 2 Wyllie and Southwick,3 poupon, Loy, and Tixier,4 and by Perkins et al.5 Most of these authors consider the effects of the clays as due to the fixed negative charges on the clay lattice. These charges cause the formation of diffuse surface layers with a high concentration of positive ions. The internal solution of the shaly reservoir rock has therefore a different ionic composition and concentration than the electrolyte with which it is in equilibrium (connate water produced from the formation or mud filtrate by which the formation is invaded). To calculate the equilibrium concentration of the internal solution, use is made of the Donnan6 relation, which states that the mean ionic activities of the internal solution and of the external electrolyte must be equal. From this and the

Jan 1, 1956

By Milo W. Krejci

The plant and quarries of the Inland Portland Cement Co. are located at Metaline Palls, Wash., about 128 miles north of Spokane, on the Pend Oreille river, and within 10 miles of the Canadian border. The plant is one of a chain of cement plants controlled by the Lehigh Portland Cement Co., of Allentown, Pa. Work on this plant was commenced in June, 1910, and was completed in April, 1911, but on account of some delays in the construction of the power plant, the works were not put into operation until August, 1911. Since then it has been in continuous operation and has furnished the Inland Empire with a high grade of cement. Fig. 1 is a view and Fig. 2 is a plan of the works. Water Power Development.—The source of the water supply for the hydro-electric plant of the Inland Portland Cement Co. is Sullivan lake, a body of water approximately 5.5 miles long and&apos; 0.5 mile wide, situated in the Kaniksu Forest Reserve. A wooden crib dam was installed so as to raise the elevation of the lake 25 ft., and the additional storage capacity was taken up by the diversion of Sullivan creek into the lake by means of a wooden flume, 0.25 mile long, 6 by 8 ft. in cross-section, and a ditch 1,200 ft. long. The water from the lake follows the natural water course to an intermediate storage reservoir, which was created by the construction of an earthen dam. This pond was used in connection with the saw mill which was installed at this point. Besides the earth dam, there was also built a crib, at the point shown in the sketch map, Fig. 3. This crib dam is 35 ft. high. From this point the excess water follows the natural course of Sullivan creek to the Pend Oreille river. The water is taken from this intermediage storage by means of a 6 by 8 ft. wooden flume approximately 13,000 ft. long. This flume is built up on the side hill, piling being driven most of the way on

Jan 1, 1914

By M. Hansen, C. C. Wang

THE 6 phase of the Cu-Sn system (Cu,Sn, = 32.53 pct Sn) was considered to be stable down to room temperature until Owen and Iball showed by X-ray analysis that it undergoes a eutectoid decomposition into the a and e phases at a temperature near 300°C. Their findings have been confirmed by other investigators,2-5 a11 of whom used X-ray diffraction studies of powdered specimens. The transformation temperature has been reported by various authors as lying between 300" and 380°C. To our knowledge, no microscopic evidence of the eutectoid reaction has been published, as yet. It was in connection with other work that longtime annealings at 300°C were conducted with alloys containing 22, 32.6, and 35 pct Sn (nominal compositions) prepared from electrolytic copper and electrolytic tin and cast in a small iron mold. The specimens were first annealed at 700°C for 5½ hr and quenched from 400 °C after cooling to, and annealing at, that temperature for 9½ hr. After this treatment the sample with 22 pct Sn was cold worked for 15 pct reduction in thickness; the 32.6 and 35 pct alloys were too brittle to be cold worked. The final anneal at 300°C was done in a sealed pyrex glass bulb for 63 days. Fig. 1 represents the microstructure of the annealed alloy with 22 pct Sn. It shows primary a solid-solution crystals in a matrix of the (a + 8)-eutectoid formed at 520 °C. The a crystals contain 8 inclusions which precipitated from a due to the decrease in the solubility of tin in copper with fall in temperature. The decomposition of the 8 phase into a (light) and E (dark) can clearly be seen in some areas of the (a + 8)-eutectoid matrix. However, the decomposition is far from being completed, even after the long-time anneal used. Figs. 2 and 3 depict the microstructures of the annealed 32.6 pct alloy, which was intended to consist entirely of 6 phase. Due to some loss in copper on melting, the composition is slightly higher in tin. Accordingly, the sample after quenching from 400 "C consisted of grains of the 8 phase with the e phase arranged along the grain boundaries and as a Wid-manstatten precipitate within the 6 grains. After an annealing time of 63 days, the eutectoid decomposition, 6 + a + e, is still in its early, initial state. The pearlitic type of eutectoid is nucleated at the c crystals, preferably those surrounding the grain boundaries of the 8 phase. The appearance of the (a + €)-eutectoid in the 35 pct Sn alloy was very similar to that shown in Figs. 2 and 3. Again, the eutectoid decomposition nucleated at the 6 phase and proceeded from there into the 8 areas. As is evident from Fig. 2, the rate of decomposition of the 6 phase at 300°C is extremely sluggish: In the representative area shown only about 5 pct of the 8 phase has undergone the eutectoid trans- formation after annealing for 63 days. On the other hand, Owen and Williams2 have reported that X-ray photographs of powdered samples with between 17.5 and 34 pct Sn did not show 8 lines after annealing for only five to seven days at 300°C. This is in accordance with the fact that the rate of reaction in powdered samples is higher than in massive specimens, as a result of the excess free energy of the powder (due to its greater surface area). The authors wish to express their thanks to C. A. Johnson for preparation of the micrographs.

Jan 1, 1952

President H. M. Howe, Boston, Mass. (communication to the Secretary): Le Chatelier&apos;s pyrometer is certainly a most convenient and accurate instrument for the laboratory, and one that may be used under some conditions in the mill. I have used it for several years and with great satisfaction. Like Prof. Roberts-Austen and unlike Herr Blass, I have always found that its indications remain constant over long periods. Like Prof. Roberts-Austen, also, I find it possible, in a quiet place, to read with extreme accuracy ; and, by the use of a telescope, I can read temperatures to within a degree, for some delicate determinations which I have in hand. Variations in the temperature of the room affect the readings of the instrument far less than one would expect. When the current is cut off, the mirror does not always return exactly to the same place; in other words, the zero shifts appreciably, and must be determined often, indeed every few hours if accuracy be desired. In some cases I have had it determined within a very few minutes of every important reading. To this end a switch should he introduced, so that the circuit may be broken readily. With this arrangement we can determine accurately the position of the zero within a very few seconds of the time of taking any especially important reading. The chief causes of the variation of the zero which I have noticed are as follows: a. The suspension may not be tight enough, so that the momentum of the galvanometer frame as it swings makes its supporting wires slip in their bearings. b. Changes in the position of neighboring iron objects may deflect the mirror. c. Changes in the temperature of the room may, perhaps, change the torsion of the suspension wires, and so shift the mirror. d. Dust may attach itself to the galvanometer frame, and by friction against the surrounding fixed parts of the galvanometer, may

Jan 1, 1895