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By Robert S. Dewey

AS a result of drilling operations during 1943, West Texas again added sufficient new oil reserves to replace the oil produced during the year, but failed to maintain its position in currently available reserves because the deeper discoveries will require years for development. Drilling failed to provide the additional oil necessary to meet the increase in current and anticipated market demand. Although 13.3 per cent of the total footage drilled was in wildcat exploration, the ratio of oil discoveries to total wildcats was less in 1943 than in 1942, but comparable to that in 1941. Of the 732 field wells completed, 270 were at Slaughter, 55 at Wasson, 45 at Mascho and 31 at North Cowden. As of Dec. 31, 1943, there were 361 drilling wells including 71 wildcat and 290 field wells; 19.7 per cent were wildcats. It is anticipated that the percentage of wildcats of the total wells will be higher during 1944 than in either 1942 or 1943. Tables 3 and 4 present a three-year comparison of drilling activity and illustrate the downward trend of development that has been in effect during that time. Because of development lag in the deeper Ordovician fields, several years elapse before 2 sufficient number of wells is completed to give a substantial producing rate. As these new oil reserves cost more to find, and will cost more to produce on a barrel basis than the oil marketed during the year, their reserve replacement value to the industry is less in money. Costs While complete costs for deeper drilling are not yet available for analysis, it is evi- dent from the data on drilling rates to comparable depths, contract prices, and general increases in costs, that the cost of drilling has risen approximately 20 per cent during the year. One representative drilling contractor estimates that the average drilling time on a 5000-ft. field well has increased nearly one third and that out-of-pocket costs have increased a dollar per foot. Three major factors contribute to this increased cost: (I) less experienced labor, (2) deterioration in mechanical equipment and expendable material, and (3) increased contract prices. In the past, when there were more drilling rigs than wells to be drilled, some contractors would cut their drilling profit to keep their personnel and rigs working. As this practice is no longer necessary, the contract prices are adjusted upward to assure a profit. On deep and difficult drilling, contracts are let on a cost plus basis. A number of mechanical difficulties have become evident. Inferior quality of steel used in drill pipe and rock bits has added appreciably to drilling time and cost. Contractors are experiencing delay in obtaining repair work and repair parts for prime movers. As the length of drilling time required an shallow-field wells has not increased in proportion to that on deeper wells, it seems that the medium-sized drilling rig is better adapted mechanically than the heavy one to the work imposed. One of the main deficiencies in the heavy rig equipment is inadequate pump capacity. Drilling Mud The increasing amount of deep drilling has emphasized the importance and relationship of good mud to efficient and suc-

Jan 1, 1944

By Robert S. Dewey

AS a result of drilling operations during 1943, West Texas again added sufficient new oil reserves to replace the oil produced during the year, but failed to maintain its position in currently available reserves because the deeper discoveries will require years for development. Drilling failed to provide the additional oil necessary to meet the increase in current and anticipated market demand. Although 13.3 per cent of the total footage drilled was in wildcat exploration, the ratio of oil discoveries to total wildcats was less in 1943 than in 1942, but comparable to that in 1941. Of the 732 field wells completed, 270 were at Slaughter, 55 at Wasson, 45 at Mascho and 31 at North Cowden. As of Dec. 31, 1943, there were 361 drilling wells including 71 wildcat and 290 field wells; 19.7 per cent were wildcats. It is anticipated that the percentage of wildcats of the total wells will be higher during 1944 than in either 1942 or 1943. Tables 3 and 4 present a three-year comparison of drilling activity and illustrate the downward trend of development that has been in effect during that time. Because of development lag in the deeper Ordovician fields, several years elapse before 2 sufficient number of wells is completed to give a substantial producing rate. As these new oil reserves cost more to find, and will cost more to produce on a barrel basis than the oil marketed during the year, their reserve replacement value to the industry is less in money. Costs While complete costs for deeper drilling are not yet available for analysis, it is evi- dent from the data on drilling rates to comparable depths, contract prices, and general increases in costs, that the cost of drilling has risen approximately 20 per cent during the year. One representative drilling contractor estimates that the average drilling time on a 5000-ft. field well has increased nearly one third and that out-of-pocket costs have increased a dollar per foot. Three major factors contribute to this increased cost: (I) less experienced labor, (2) deterioration in mechanical equipment and expendable material, and (3) increased contract prices. In the past, when there were more drilling rigs than wells to be drilled, some contractors would cut their drilling profit to keep their personnel and rigs working. As this practice is no longer necessary, the contract prices are adjusted upward to assure a profit. On deep and difficult drilling, contracts are let on a cost plus basis. A number of mechanical difficulties have become evident. Inferior quality of steel used in drill pipe and rock bits has added appreciably to drilling time and cost. Contractors are experiencing delay in obtaining repair work and repair parts for prime movers. As the length of drilling time required an shallow-field wells has not increased in proportion to that on deeper wells, it seems that the medium-sized drilling rig is better adapted mechanically than the heavy one to the work imposed. One of the main deficiencies in the heavy rig equipment is inadequate pump capacity. Drilling Mud The increasing amount of deep drilling has emphasized the importance and relationship of good mud to efficient and suc-

Jan 1, 1944

US 4,190,434 - In the thermal production of magnesium metal, a mixture of calcined dolomite, an iron- silicon-aluminum alloy as a reductant, and residual slag from the production of ferrochromium is smelted to evolve magnesium vapor, which is then condensed. The use of bauxite is lessened or eliminated because of the relatively high alumina content of the residual slag. R. Bonfils, A. Mena, C. Payn, and L. Septier, assigned to Ste. Francaise d’Electrometallurgie (SOFREM). Feb. 26, 1980. 6 pp. (75-10R). Filed: 6-14-78 (915,387). Priority: France, 6-24-77 (77/20,227).

Jan 1, 1982

By A. Thielen

In experiments for the production of steel the principal problem has always been the introduction into, or removal from, the iron of a definite quantity of carbon. Although the solution of this problem had engaged a more or less blindly and empirically directed effort for a long time, it was only with the development of analytical chemistry that the rôle which carbon plays in the constitution of steel was disclosed in its full significance, and that many of the problems confronting the steel-maker were thereby more clearly defined than before. For a long time, and to a certain extent even to this day, the percentage of carbon in steel has been the controlling means of deter mining its quality and hardness. In many cases the percentage of carbon alone has been relied on for judging large consignments, such as the large deliveries of wire-billets and blooms to America during the past twenty years; and though to-day the influences of the other constituents are recognized and many other considerations are taken into account, and though, moreover, some special steels, such as the Hadfield manganese steel, apparently dispense to a certain extent with the assistance of the carbon, yet fix our Bessemer, Thomas, Siemens and crucible steel the carbon still remains one of the most important constituents, and I venture to say it is indispensable. In order to produce in the Bessemer converter a steel of a certain required percentage of carbon, two methods, as is well known, present themselves. By the one the decarburization process is stopped when the desired carbon limit in the bath has been reached ; by the other the bath is completely decarburizecl, and then a calculated amount of carbon added in the form of spiegel, ferro manganese, etc. In Germany the latter method only was adopted, and it was retained when the Thomas-Gilchrist process for the production of low-Phosphorus steel from high-phosphorus iron eame into use, since from the nature of the new process complete decarburization is neces-

Jan 1, 1891

By H. E. Lee, D. Ingvoldstad

AT Bunker Hill the original charge storage and preparation system was installed in 1917 to accommodate lead-silver gravity mill products. Only minor tonnages of wet fines such as vanner and flotation concentrates were received. Charge flux and diluent requirements were provided by an ample supply of siderite middlings and coarse lime-rock. While oversize material was crushed through %-in., the use of roll crushers in series resulted in a more or less granular, free-running charge of adequate porosity. Under such conditions, receipts could be proportioned directly from receiving bins, and suitable blending was obtained by passing the resultant layered composite through a small Stedman disintegrator. This elementary system served well for production and smelting of an extremely lead-rich sinter, in the low column blast furnace. Here sinter physical quality is less critical, and appreciable quantities of raw flux and oxidized ore may be charged directly to the blast furnace without seriously impairing furnace capacity. Prior to 1938 the relative proportions of zinc receipts were low and extraneous flux requirements at a minimum. However, subsequent war-inflated zinc demands brought marked increase in fine concentrate and slimy zinc leach residue receipts and an abrupt introduction to smelting a more refractory zinciferous charge. The higher temperature demands of the more refractory zinciferous charge required a higher smelting column and the higher column, in turn, rendered the blast furnace less receptive to improperly prepared feed. Inadequate presinter processing facilities prevented the production of acceptable sinter, and blast furnace production declined to 50 pct of former capacity. In view of a prevailing contention among lead metallurgists as to the deleterious action of high zinc slag on blast furnace capacity, it was natural to overstress this factor and to concentrate on possible changes in furnace design. Another interpretation was that primary correction should be sought through expanded sintering facilities. This divergence of opinion, together with the extreme material shortages of the 1940's, delayed corrective

Jan 1, 1957

By F. A. Olson, S. L. Pohlman

A unique method of measuring weight loss as a function 3 of time, with a sensitivity of 10-5 grams, while leaching copper minerals with a flowing acid leach solution has been developed. Kinetic results obtained coupled with visual and microprobe analyses show topochemical reaction for the leaching of chrysocolla with sulfuric acid. The kinetics follow a shrinking core model and show ion diffusion through a product layer, chemical reaction at the unreacted core interface and mass transfer through the boundary layer as being important.

Jan 1, 1974

A New Ingersoll-Rand Turbo Blower The Ingersoll-Rand Co. has added to its Turbo Compressors and Blowers a low-pressure machine t o handle volumes from 3,000 to 35,000 cu. ft. per minute at from 1-2 ½ lb. These are particularly adapted to such service as foundry cupola blowing, atomizing oil for oil burners, supplying blast to heating and annealing furnaces of various kinds, blowing air for water-gas generators, pneumatic conveying and ventilating. They are of the single stage, double flow type and are furnished either electric motor, steam turbine or water wheel driven.

Jan 6, 1916

By L. A. Price

With increased stripping ratios and with dwindling ore content, the mining fraternity is increasingly turning to larger and larger equipment for profitable open pit operations. The availability of higher horsepower prime movers and increased-capacity electric transmissions using either wheel-mounted or axle-mounted traction motors makes a reality of single-axle, rear dump trucks having 150 to 250 ton capacity. The size of electric loading shovels is inherently geared to the size of haulage equipment. To work effectively with this new generation of trucks, the Harnischfeger Corporation has introduced its P&H Model 2800 with a capacity of 20 to 25 cu yd and a working weight of nearly 1,500,000 lb. The Model 2800, depicted in Figure 1 loading a 200 ton truck, has many new electric and mechanical features designed to give excellent production and low cost operation. Chief among the new features is the ELECTROTORQUE control system. Electrotorque is a completely static, solid state electronic system supplying controlled power both to the armatures and to the fields of the d-c shovel drive motors. It eliminates many major electrical rotating machines and their attendant maintenance. The system was developed jointly by ASEA of Sweden and Harnischfeger Corp.

Jan 1, 1970

By C. E. McManus

MANY mechanical advances have been made on mining equipment during the year 1951. There have been a number of trends established and many modifications made on open-pit equipment to increase the efficiency and availability of all the machines necessary in the moving of overburden and iron ore. Some years ago, the trend toward larger shovels for the loading of off-highway trucks began, but in the last year, it has become general practice to use the 5 to 7 ¼ -yd quarry-type shovels in the loading of haulage units. For years these larger shovels were used in the locomotive haulage pits. As the truck capacities increased from 15 to 20 to 30 tons, the need for larger loading units became apparent. Today in most mines, large shovels are in evidence and a few 8-yd shovels will be delivered this year for loading off-highway trucks. Torque Converter-Shovel The Diesel-driven shovel with its friction bands has been modernized with the torque converter. There have been about ten shovels remodeled to take a torque converter in the drive system. The large high-torque, low-speed Diesel engine was removed and replaced by a high-horsepower, high-speed, automotive-type engine. This engine was connected directly to the torque converter. The torque converter was connected to the shovel through the standard original sprocket and chain. Dual governors controlled engine performance. One governor controlled the high idle of the engine; the other governor, which is connected through a flexible shaft to the output shaft of the converter, controlled the loading of the engine. With this dual governor hook-up, the engine anticipates load conditions and is operating at high idle and full throttle before the shovel load is transmitted back through the converter to the flywheel. It has been found that with this automotive-type engine and converter, the shovel capacity has been increased about 20 pct. Also, the wear on the friction bands, breakage of hoist cables, and other mechanical breakages has been reduced materially. Alloy-Steel in Shovels The shovel equipment manufacturers have been experimenting with low-temperature-strength, high-alloy steels to combat the excessive breakage that occurs in extremely cold weather. High-nickel alloy steel has been used in critical areas that are affected by low temperatures, the most notable being dipper sticks. Most shovels ordered today are equipped with some of this special, alloy steel. More and more manganese alloy is being used for replacement parts such as shovel pads, idlers, drive sprockets, etc. Although the initial cost of these parts is considerably higher than the standard replacement items, the life of these manganese parts is considerably longer and well worth the added expenditure. Dipper-teeth repair is still a problem. Most companies use the small replaceable inserted tooth. It has become common practice among some of the companies to "job out" their dipper-tooth repairs to outside welding companies. This necessitates an additional inventory of teeth, but it does guarantee an adequate supply of replacement teeth at all times. These contractors have set up their shops on a production basis and can do an acceptable job at a high rate of speed. Thermite welding has been used in retipping teeth. To date, the process cannot be called successful but with improvements the time required to repoint the dipper teeth will be decreased considerably. The submerged arc process has been tried in the replacement of these dipper points, but like thermite welding has not proven successful. Here again, if a method can be developed to use submerged arc, the job of teeth repair will be made much easier. New model shovels in 6 ½ and 8 cu yd sizes fea-

Jan 1, 1952

By B. M. Larsen, J. W. Campbell

Several articles have recently been published discussing the conditions necessary for accurate measurements of temperatures in the open-hearth steel furnace. In the course of a study of refractories service conditions in steel furnaces, the present writers have taken temperatures in several open-hearth shops in the Pittsburgh district. The conclusions, as to conditions necessary for accurate measurements of temperature, are somewhat at variance with those of other investigators. The subject is closely connected both with the close control of steel-making and the prevention of overheating of the silica refractories used in roofs and walls. It is becoming more and more important to obtain furnace temperatures of fairly definitely known accuracy. At present, the most useful instrument for such measurements is the disappearing-filament type of optical pyrometer. This method of measurement has formed the basis of most other discussions on the subject and was also used by the writers. Previous Investigations In 1916, Burgess' made perhaps the first systematic series of measurements in steel furnaces. The emissivity figures of 0.40 for liquid steel and of 0.53 to 0.65 for liquid slags had been determined by the Bureau of Standards and were used by Burgess in this work. These correction factors are still being used and are regarded as fairly accurate, so that the tapping and teeming temperatures on metal streams given by Burgess should be very nearly correct. Most of his temperatures of furnace roofs and slag surfaces were taken while flames were present in the furnaces and include a few roof temperatures above 1700' C. (3100' F.).

Jan 1, 1927

By H. NORTON JOHNSON

THE oil industry in California during 1929 reached new heights and new depths in the discovery and development of the oil resources of the State. The discovery of new fields, and more especially the discovery and development of deeper prolific sands in known fields has, for the first time in its history, brought the potential production of completed wells within the State to over 1,000,000 bbl. oil per day. Constant improvement in equipment and technique has made possible economic development to depths unheard of but a few short years ago. Commercial production from a depth of over 4000 ft. was considered quite an accomplishment in 1923 when the Meyer sand at Santa Fe Springs was developed, and when later oil was successfully raised from this depth.

Jan 1, 1930

Discussion of the paper of Robert Henry Lee, presented at the New York Meeting, October, 1913, and printed in Bulletin No. 82, October, 1913, pp. 2515 to 2522. J. E. JOHNSON, JR., New York, N. Y.:-This subject is of great and increasing importance, as the exhaustion of the deposits of ore of ideal character compels the iron industry to turn more and more to those which are less desirable on account of physical structure as well as analysis. Thus there has come about the use of the Mesabi ores in this country and also of the Minette ores in Europe, which produce far greater percentages of flue dust than did the lumpy ores first used. It is a matter of common knowledge that the utilization of this flue dust, containing commonly 50 per. cent. or more of metallic iron, has been a problem very difficult and tedious of solution. The number and variety of the solutions now offered is a sufficient proof of this. . I have no intention of going into the merits or demerits of any of these processes as such, but there are certain considerations concerning the effect of their product on the operation and fuel economy of the blast furnace which I believe to be new and which I desire to bring out. There are two methods, so different as almost to be direct opposites of each other, whereby an ore may exercise an unfavorable effect on the economy of the blast furnace. The first of these is well known and results from the ore being refractory and highly resistant to the action of the reducing gases of the blast furnace. This results in its being incompletely reduced when it reaches the zone of fusion and in the reduction being finished by the direct action of carbon in the lower portion of the furnace. This is so well understood as to need little elaboration or comment. There is, however, another action which may be equally as fatal to the economy of the furnace as the foregoing, and as this point is, to the best of my knowledge, not generally appreciated, it is one upon which I desire to lay particular stress. This consists in the ore being, in a sense, too reducible.

Jan 12, 1913

Jan 1, 1963

By Charles Jones

IN the winter of 1902, while occupying the position of mining and examining engineer for the Mountain Copper Co., Ltd., of Keswick, Cal., I had occasion to discuss with the General Manager, among other things, the question of the enormous waste of sulphur in smelting cupriferous, pyrite ore, and to cast about for means to utilize this waste or to render the fumes innocuous to vegetation. The decreasing rate of production of California farms, the consequent need of fertilizers, and the opportunity thus offered to utilize large quantities of sulphuric acid in the manufacture of superphosphates naturally brought the subject to the practical and commercial side of phosphates. I was informed that the company had made efforts to find phosphates in the West, without success. I advised as a start placing inquiries for phosphate deposits on the Pacific coast in the current mining ,journals. This was done, with the result that in January, 1903, from an advertisement in the Mining and Scientific Press we got track of a deposit in Rich county, Utah, through T.J . Wilson, of the Southern Pacific railroad in San Francisco. As soon as snow in the mountains would permit, in May, 1903, I undertook an examination of the property, with the result of recognizing the importance of the find, in spite of its lack of facilities for transportation at a commercial figure. On June 15, 1903, I concluded my report by saying, "This may be one of the world's deposits of phosphates." On Nov. 17, 1903, I concluded my report for the season in the following words : " I have now no hesitation in saying that I believe the Carboniferous formation so largely developed in the Wasatch mountains of Utah and the mountains of the Great Basin will prove to be one of the greatest storehouses of phosphoric acid in the world."

Jan 10, 1913

By Sherwin F. Kelly

Twenty five years of exploration has shown that the "geophysical dollar" is worth $1780 in the Orange Free State, $1488 on the Witwatersrand, $85 in Sweden, $28,000 in the Transvaal and $3500 or more in the U.S.

Jan 6, 1951

By B. W. Prof. Frazier

I PROPOSE in this paper to treat of the chimney merely as a heat engine, as one of the devices resorted to in practice for the conversion of heat into mechanical work. For the sake of simplicity and clearness in the discussion, let us consider the subject in its simplest form. Conceive a chamber, heated from without, in free communicatioH at one end with the external atmosphere, and at the other end opening into a vertical chimney. Let the. cross-section of the chamber be so great, relatively to that of the chimney, that we can neglect the actual energy of the air passing through the chamber. We will neglect, also, all passive resistances to the passage of the air. We will assume that the cross-section of the chimney is constant, and that the air in passing through it neither gains nor loses heat. The following symbols will be employed in the discussion : Po = the normal pressure of the atmosphere, which, it is assumed, is the pressure existing at the level of the chamber. Po = 10332.96 kilograms per square meter. P2 = the pressure of the external atmosphere at the top of the chimney. To = the, absolute temperature of melting ice by the centigrade scale. This is assumed to be the temperature of the external air at the level of the chamber. To = 273°. T2 =the absolute temperature of the air as it passes from the chamber to the chimney. T3 =the absolute temperature of the air as it issues from the chimney. to, t2, t3 are the temperatures, as recorded on the centigrade ther¬mometer, corresponding to the absolute temperatures To, T2, T3 re-spectively to = 0° C. In general, t = T- 273. Io, I2, I3, represent the intrinsic energy of the air at the temperatures To, T2, T3 respectively.

Jan 1, 1882

Carlisle: An old friend and good friend, Alan Bateman, is the Silliman Professor of Geology Emeritus at Yale and editor of the Journal of Economic Geology. Now, Alan, let's start off by telling us something about how you became interested in copper. Bateman: Well, after I left Yale in 1913, I was appointed one of the field members of the Secondary Enrichment Investigation. We spent three years in the field studying all the copper deposits of North America, trying to find out how secondary copper enrichment took place. As part of this investigation, I went up to Kennecott, Alaska, in 1916. After the trip I was asked by the president of the company to become consulting geologist to them. I accepted his offer, and to this day I'm still consulting geologist to the Kennecott Copper Corp. Up at Kennecott, there were both Henry Krumb and my good friend Henry DeWitt Smith, who was general superintendent. He and I had been together at Yale, and I had ushered at his wedding. Interestingly enough, Henry took his bride to Alaska and I took mine there two months later. My assistant was Don McLaughlin, and I think that was his first experience in a mining camp. We published a paper on Kennecott together and cemented a friendship lasting to this day.

Jan 11, 1964

By Jasper L. Stuckey

PYROPHYLLITE, first identified as soapstone,1 later as agalmatolite,2 and finally as pyrophyllite,3 has been known to occur in North Carolina for more than 130 years and has been produced intermittently in commercial amounts for the past 100 years. Pyrophyllite mining, however, has become a major industry in North Carolina only during the past 25 years. North Carolina and California are the chief producing states. Current annual production averages 125,000 tons, of which slightly more than 90 pct comes from North Carolina. Distribution and Geologic Setting: All known pyrophyllite deposits in North Carolina are associated with rocks of the Carolina Slate Belt,4 which is composed of a vast series of metamorphosed volcanic and sedimentary materials, occurring as two zones extending in a northeast-southwest direction across the state. The larger of these zones, lying in the central Piedmont region, varies from 8 to 50 miles wide. The smaller zone lies along the eastern edge of the Piedmont region and is partly covered by coastal plain sediments.

Jan 1, 1958

Jan 1, 1969

By G. Thodos, R. B. Grieves

A method has been developed for the accurate calculation of the cricondentberm and cricondenbar temperatures of multicomponent hydrocarbon mixtures of known composition. The mixtures may contain any number of components including paraffins and isoparaffins, olefins, acetylenes, naphthenes and aromatics. This approach is based upon the mole fraction of the low-boiling component in the mixture and graphically presents the ratios of the cricondentherm and cricondenbar temperatures to the pseudocritical temperature as {unctions of a boiling-point parameter. The only requirements are the critical temperature, normal boiling point and the approximate vapor pressure behavior of each component. For mixtures of more than two constituents a stepwise calculation procedure is necessary where the pseudocritical temperature is based upon the critical temperature of the pure low-boiling component and upon the actual cricondentherm or cricondenbar temperature of the mixture of all the remaining higher-boiling components. From an analysis of 22 binary systems (123 compositionsl, the average deviation of calculated cricondentherm temperatures from reported values is 0.87 per cent, based on degrees Rankine; and for 10 multicomponent mixtures containing from three to six components, the average deviation is 0.98 per cent. From an analysis of 18 binary systems (104 compositions) the average deviation of calculated cricondenbar temperatures from reported values is 0. 79 per cent; and for 15 multicomponent mixtures, 1.47 per cent. Equations, derived from the graphical relationships, are presented which enable rapid calculations for both binary and multicomponent systems. INTRODUCTION With the increasing tendency towards the use of high pressure processes, the need for an accurate method of calculation of the properties of a multicomponent hydrocarbon mixture in the critical region is becoming more essential. Critical region phase relations are also significant in gas condensate reservoirs, for which a knowledge of the fluid phase boundaries and regions of retrograde condensation make it possible to evaluate optimum operating conditions. The possibility of liquefaction in the underground structure may be established, and information on the feasibility of the use of repressurizing may be determined. A typical phase diagram for a multicomponent hydrocarbon mixture is presented as Fig. 1. This figure also shows the regions of retrograde behavior encountered by following lines AB and AC. If accurate methods of calculating the temperatures and pressures at the critical, cricondentherm (maximum temperature) and cricondenbar (maximum pressure) points of multicomponent hydrocarbon mixtures of known composition were available, it would be possible to estimate closely the entire phase diagram of any mixture. Several methods have been presented in the literature for the estimation of the critical temperatures and pressures of multicomponent mixtures containing all types of hydrocarbons and including the fixed gases.4-8,21 Considering the cricondentherm and cricondenbar points, the work is more limited. Etter and Kay5 have developed rather complex equations for