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Slovenliness is as reprehensible in words as in clothes. Much writing that we recognize as poor in style is merely sloppy. Just as some students postpone the necessary shave or forget to change their collars, so young engineers in writing drop their articles, definite and indefinite, or omit prepositions where they are required, possibly to compensate for those they use unnecessarily The work will begin [on] Saturday. Influenza seriously affected many mines [during] the last three months. Flotation in America [during] the last two years has made tremendous strides. Construction of the mill started [on] August 12, 1915, at which time 75% of the excavation was completed. The idea I wish to convey is [that] there are mineral deposits to which the present law applies badly. For this reason, if there was [for] no other, the ownership of the ore below and [of] the surface above should go together. When a unit of mapping is furnished, be the unit a claim or [a] group of claims, it is necessary . . . A fully stocked store was started in Park City and all employees [were] sold merchandise on a strictly cost basis. The word "merchandise" is left without government or agreement. 'I suggest: ". . . and merchandise was sold to all the employees on a strictly cash basis." The verb 'be' is serving concurrently both as a principal and as an auxiliary in the following: At first the work was interesting and [was] liked by most of the men. The sulphide ore was more complex or [was] milled at an increased cost. The failure to repeat the auxiliary verb in successive clauses is a common error, as in The filter is filled with liquid allowed to empty, and then ignited.

Jan 1, 1931

By Donald H. Beilstein

The St. Joe Minerals Corporation Lead Smelter and Refinery have been in continuous operation at Herculaneum, Missouri since 1892 as the Herculaneum Lead Smelting Division. Over the years, the plant has undergone many changes to increase production, improve the technology, reduce the cost of operations, and produce the highest grade of primary lead. The latest alterations were begun in 1950 and completed in 1970 and have resulted in the Herculaneum Smelter capacity being increased to in excess of 200,000 tons per year (180,000 metric tons). This increase has made the Herculaneum Smelter the largest in the United States, and second largest in the world. This paper will describe the Herculaneum Smelter equipment, processes, and material balances. Particular emphasis will be given to the McDowell-Wellman 10' x 100' (3 x 30 meter) up-draft sinter machine and ancillaries; to the new Heavy Smelting Department (blast furnaces and drossing section); to the new Lead Refinery and its automatic casting equipment and to the gas handling system including the 340 tons per day (305 metric) Sulfuric Acid Plant utilizing a -four pass converter. The description will include photographs, flow sheets, tonnages and assays where applicable.

Jan 1, 1970

By C. C. Wright, R. J. Day

ALTHOUGH data on the exact tonnage of recoverable coal silt are not known, the quantity produced in 1943 was estimated to be over five million tons for the anthracite region of Pennsylvania alone. Since that time the recovery of the No. 5 buck- wheat size previously included in silt estimates has increased greatly thus reducing the total silt tonnage. As a compensating factor, however, the methods of recovering silt previously escaping into the rivers and streams have been markedly improved so that the net figure may not have changed materially. Comparable estimates for bituminous coal are lacking, but undoubtedly the silt represents a significant tonnage. With the trend toward increased wet cleaning of the smaller sizes of bituminous coal, it is to be expected that even greater quantities of silt will be available in the future. The raw silt from anthracite collieries usually contains a high mineral matter content, but technological developments in fine coal cleaning have been making rapid advances and it appears probable that more extensive use of these methods will be employed in the near future. Bituminous coal silt in many instances contains a similar high mineral matter content. As with anthracite silt, however, the cleaning of this material, where necessary, appears both technologically and economically feasible. With a view to upgrading the size and value of silt, considerable laboratory and pilot plant work has been conducted by a number of organizations on what is commonly known as pelletization. Actually the process is one of extrusion in which the moist silt is extruded from a die in the form of rods, which usually break into relatively short lengths-a few inches long-as they fall from the die. Fig I is a photograph of some extruded 3/8-in. diam pellets and of the anthracite silt from which they were produced. This technique of producing larger sized material from fines is by no means new, having been used extensively by the industrial carbon and clay industries for years.' The application of the process to coal silt appears, however, to be relatively new. The first major program of investigation dates back only to July 1945, when a group of engineers representing the Anthracite Institute, The Pennsylvania State College and the J. F. Pritchard and Co. conducted preliminary tests on the extrusion of anthracite silt at the Floridin Co. plant at Warren, Pa. Since that time these three organizations-individually, together, and in co- operation with other interested groups- have actively pursued work on various phases of the problem. Much of the early history and details of the laboratory and pilot plant work by the Anthracite Institute, has been reported by Mulcey and Eckerd.2 It is the purpose of this paper to report additional information on the process, especially with respect to the factors influencing the quality and use properties of the product, and the current develop

Jan 1, 1948

By C. H. Lieb

ONE astounding fact in the production of petroleum is the comparatively recent realization by producers that flowing production is the cheapest crude produced. About 1910 or even later, operators actually endeavored to get a producing well to pumping as quickly as possible after completion. A well was not really considered to be completed until it was operating on the pump. Remarkable progress has been made since then. It was not until about 1920 that producers began to take a serious interest in pressures and to think a little about proper methods of handling oil wells. Pressure gauges were installed, and records of pressures maintained, which was quite an innovation. Desultory experiments were made with tubing of different sizes, as well as experiments with placing the bottom of the tubing string at different levels in the well. Probably the first important departure from customary procedure was about 1926, during the Seminole development, when gas lift

Jan 1, 1936

By William R. Chedsey

ALTHOUGH few changes can be reported in educational methods at the mineral technology schools during 1940, other events have taken place of direct interest to, and that will have a profound effect upon, mineral industry education on the United States. In the erection of new buildings, some notable changes have been made on the campus, The U.S. Bureau of Mines Experiment Station at the University of Utah, Salt Lake City, was dedicated on May 20. The construction and equipment of this building cost between $300,000 and $400,000. It will be the general headquarters for the metallurgical division of the Bureau and will have a pronounced effect upon the mineral industries research program at the University.

Jan 1, 1941

By C. WIFLARD HAYES

(New Haven Meeting, February, 1909.) I DESIRE to make it perfectly clear at the outset that I fully realize the hazardous nature of any attempt to estimate the quantity of iron-ore or any other mineral in the ground. I should not have had the temerity to venture upon an inventory of the iron-ore supplies of the United States except for the requirements of the Conservation Commission. During the preparation of this inventory I have been impressed by the wide diversity in estimates of those best qualified to. hold an opinion, and I am therefore prepared in advance for criticism of my figures. Inasmuch as this report was prepared in large part for unprofessional readers, I considered it necessary to classify and describe the commercial iron-ores in a somewhat elementary manner, in order to explain the reasons for the large element of uncertainty in the estimates. I have therefore given a chemical and a geological classification of iron-ores, which place the commercial deposits in six classes: (1) magmatic segregations in basic igneous rocks; (2) contact-deposits formed in connection with igneous intrusions; (3) concentration-deposits; (4) replacement-deposits; (5) bedded-deposits, and (6) gossan-deposits. The iron-ores are further distinguished under two classes available and not available. This classification is in large measure arbitrary, and it, is evident that it will vary front time to time. In the available class are placed those ores which can be worked at a profit under conditions essentially as they exist at present. Since it depends wholly on the question of costs, the various factors which affect cost will determine the classification of any particular deposit. Actual production, * Abstract of Report prepared for the Conservation Commission. t Chief Geologist, United States Geological Survey. .

Apr 1, 1909

By Alfred H. Bell, Virginia Kline

In 1944, Illinois produced 77,413,000 bbl. of oil, or 4.6 per cent of the total for the United States, and continued to rank sixth in the nation in oil production. This represents a decrease of 6 per cent from 1943, when- the total Illinois production was 82,256,000 bbl. This decrease was much less than the 23 per cent decrease in 1943 from production of the previous year. The principal factor in arresting the production declinc, which had been going on since 1941, seems to be the increased drilling that followed the relaxing of the Federal Government's rules in regard to well spacing. The daily average production for 1944 was approximately 212,000 bbl. Daily averages by months were as follows: Jan......... 219,000 July........ 206,000 Feb......... 220,000 Aug......... 211,000 Mar........ 216,000 Sept......... 209,000 Apr......... 211,000 Oct......... 210,000 May........ 213,000 Nov........ 209,000 June........ 209,000 Dec......... 205,000 During the year, 1991 wells were drilled for oil and gas in Illinois as compared with 1791 in 1943, an increase of II per cent. Of the 1991 wells, 430 are classified as "wildcat" as compared with 461 in 1943. Twenty-eight new pools (Table 2 A) were discovered in 1944 as compared with 29 in 1943. Changes in federal drilling regulations, permitting closer spacing of wells, resulted in a drilling program that emphasized development of proved acreage rather than wildcatting. Data on production and drilling by fields are given in Table I; data on annual production and drilling for Illinois, in Table 3. Discoveries Twenty-eight new fields (Table 2 A), 42 extensions (Table 2 B), and 39 additional producing zones in existing fields (Table 2 C) were discovered in 16 counties in Illinois during 1944. Of the 28 new fields, one was abandoned during the year, 14 were one-well fields, eight others had not more than 6 wells, one had 8, one had 9, one had 11, one had 15, and the largest new field, Roaches North, had 28 producing wells at the end of the year. In all, 109 wells were producing in these new fields on Jan. 2, 1945, as compared with 111 wells producing from 29 new fields at the end of 1943. . The average initial production of the discovery wells of the 28 new fields was 129 bbl. of oil and II bbl. of water, a notable decline from the average initial production of 194 bbl, of oil and 15 bbl. of salt water for the 1943 discovery wells. In fields discovered since 1936, the total number of oil wells producing at the end of 1944 was 12,335. Productive Acreage The area of proved production in the new fields (discovered since 1936) increased from 144,335 acres at the end of 1943 to 173,485 acres at the end of 1944 (Table I), an increase of 29,150 acres. Of this increased area, 1720 acres are in fields discovered during 1944 and 27,430 acres are in extensions of fields discovered earlier.

Jan 1, 1945

By A. L. Foell

The development of the modern blast furnace began more than one hundred years ago, with the abandonment of the small hillside furnaces. Its development, especially during the past 50 years, has been accomplished through a rapid succession of enlargements and improvements. The remarkable growth in furnace output during this period is a tribute to the engineers and operators who have constantly endeavored to build larger and more efficient blast furnaces. The blast-furnace operators and their mechanical and electrical maintenance staffs have originated most of the furnace improvements as a result of their practical operating experience. Furnace Lines About 50 years ago furnaces consisted of hearths about 11 ft. in diameter, which merged into rather high flat boshes, with no cylindrical section between the bosh and inwall and no cylindrical section at the stock line. Since then the lines of the furnace invariably have included a cylindrical section above the bosh and a cylindrical section at the stock line. Notable increases have been made in both hearth diameters and furnace heights. During the past 10 years hearth diameters in new and replaced furnace stacks have rather consistently fallen within the range of 25 to 28 ft. while their heights have varied be- tween 100 and 106 ft. The lines of most large furnaces using Mesabi ores have followed a fairly uniform pattern (Fig. I) in which the principal dimensions for 25-ft. hearth furnaces are as follows: Hearth diameter............... 25 it. o in. Height of bosh................. 10 ft. o in. Bosh angle.................... 81 1/2º Diameter top of bosh........... 28 ft. 0 in. Inwall batter per foot........... 15/16 Stock-line diameter............. 19 ft. 6 in. Large-bell diameter............. 14ft. 6 in. Height from iron notch to top ring casting...................... 100 ft. o in. In determining the size of a new furnace for the replacement of an existing stack or for an addition to productive capacity, it is not possible to formulate a procedure that can always be followed. Local conditions, requirements as to capacity, available raw materials and prospects for future expansion dictate the size of such proposed improvements or additions. However, where the immediate requirements indicate a stack or furnace of a certain productive capacity, and the future prospects indicate that more capacity can be utilized, it is well to consider building the furnace ior the ultimate capacity rather than to install a smaller hearth with provision for future enlargement. The decision to build the larger hearth and stack for the ultimate capacity probably will require no greater initial investment, since the saving in the cost of brickwork will about offset the greater cost of the hearth jacket, tuyere breast and bosh bands. In the meantime. the furnace of larger hearth dimensions, while operating below its ultimate output, will yield a better coke rate and

Jan 1, 1943

By A. L. Foell

The development of the modern blast furnace began more than one hundred years ago, with the abandonment of the small hillside furnaces. Its development, especially during the past 50 years, has been accomplished through a rapid succession of enlargements and improvements. The remarkable growth in furnace output during this period is a tribute to the engineers and operators who have constantly endeavored to build larger and more efficient blast furnaces. The blast-furnace operators and their mechanical and electrical maintenance staffs have originated most of the furnace improvements as a result of their practical operating experience. Furnace Lines About 50 years ago furnaces consisted of hearths about 11 ft. in diameter, which merged into rather high flat boshes, with no cylindrical section between the bosh and inwall and no cylindrical section at the stock line. Since then the lines of the furnace invariably have included a cylindrical section above the bosh and a cylindrical section at the stock line. Notable increases have been made in both hearth diameters and furnace heights. During the past 10 years hearth diameters in new and replaced furnace stacks have rather consistently fallen within the range of 25 to 28 ft. while their heights have varied be- tween 100 and 106 ft. The lines of most large furnaces using Mesabi ores have followed a fairly uniform pattern (Fig. I) in which the principal dimensions for 25-ft. hearth furnaces are as follows: Hearth diameter............... 25 it. o in. Height of bosh................. 10 ft. o in. Bosh angle.................... 81 1/2º Diameter top of bosh........... 28 ft. 0 in. Inwall batter per foot........... 15/16 Stock-line diameter............. 19 ft. 6 in. Large-bell diameter............. 14ft. 6 in. Height from iron notch to top ring casting...................... 100 ft. o in. In determining the size of a new furnace for the replacement of an existing stack or for an addition to productive capacity, it is not possible to formulate a procedure that can always be followed. Local conditions, requirements as to capacity, available raw materials and prospects for future expansion dictate the size of such proposed improvements or additions. However, where the immediate requirements indicate a stack or furnace of a certain productive capacity, and the future prospects indicate that more capacity can be utilized, it is well to consider building the furnace ior the ultimate capacity rather than to install a smaller hearth with provision for future enlargement. The decision to build the larger hearth and stack for the ultimate capacity probably will require no greater initial investment, since the saving in the cost of brickwork will about offset the greater cost of the hearth jacket, tuyere breast and bosh bands. In the meantime. the furnace of larger hearth dimensions, while operating below its ultimate output, will yield a better coke rate and

Jan 1, 1943

By S. J. Hruska, G. M. Pound

The critical supersaturations for appreciable nucleation rate of cadmium crystals on copper and glass substrates at 186°Kwere measured as a junction of thermal-beam energy over a range of source temperatures between 616" and 839OK. There was no effect of source temperature on critical super saturation. This implies that the adsmbate prior to nucleation is in thermal equilibrium with the substrate. THE deposition of metallic vapors on solid substrates has been found to exhibit a critical behavior in that the rate of formation of deposit increases markedly when the intensity of the vapor source is increased slightly.* Evidence of the ability of sub- where Je is the flux which would arrive if the substrate were equilibrated with bulk condensate at the adsorbate temperature. The following work was undertaken to test this hypothesis. A) Energy Exchange Between Metallic Vapor and Substrates. When a freely translating atom collides with a stationary solid body its energy and momentum undergo changes which determine whether the atom is reflected or adsorbed. An atom is considered to be reflected if it returns to a freely translating state after remaining under the influence of the body for only a time comparable to the period of oscillation of atoms on the surface. An atom which remains for a longer time is said to be in an adsorbed state. The parameter which describes the energy transfer occurring at the interface is the thermal-accommodation coefficient which may be defined in terms of energy as Ei = average energy of impingent atoms, Eeq = average energy of an emergent atom which has equilibrated with the substrate, and Eem = average energy of an emergent atom. If a temperature is assigned to each of these energies, we have at as defined by Knudsen.2 Since this allows no distinction between reflected and evaporated atoms, a more specific definition is introduced for the present purposes, namely 71 = probability that an impingent atom is transferred to an adsorbed state, aj = thermal-accommodation coefficient for reflected atoms, and aTc = thermal-accommodation coefficient for adsorbed atoms. During a time t,, the mean stay time, prior to evaporation the adsorbed atom (adatom) will interact with the substrate and this will have the net effect of transferring the adatom towards a state of

Jan 1, 1964

W. S. GRESLEY, Erie, Pa. (communication to the Secretary): A six-entry method of opening coal-mines is, or was a short time ago, practiced in the Connellsville coal-region; but Dr. Chance's method has a novel aspect; for while in the Connellsville region the main pillars are formed outside of two pairs

Jan 1, 1901

By George W. Friesen

This paper presents the historical trend and de- fines the causes of drilling cost escalation in the Gulf of Mexico during the 1970's. The three major components of escalation are: 1) inflation, 2) supply-demand imbalance (demand pull) and 3) decreases in drilling efficiency. The decade was divided into three periods. During each period one component of escalation was responsible for most of the rise in costs. From 1970 through 1973 only inflation pushed costs upward. During 1974 and 1975 a supply- demand imbalance caused most of the escalation. Since 1975, decreases in drilling efficiency have produced the major component of escalation. During any one year or period of years, the sum of the three components will give the total escalation rate. The reasons why different components contribute more toward escalation during certain years than others are shown by following the timing of oil and gas price increases, the overall quality of the acreage offered each year in offshore lease sales and the resulting drilling activity.

Jan 1, 1982

By David B. Reger

Wildcat drilling for new supplies of gas and the expansion of previously discovered oil and gas pools were the principal petroleum activities in West Virginia .during 1942. Much of the new gas exploration is still uncompleted and still indecisive but various wildcats made substantial extensions to existing pools. Out of 53 wildcats drilled 27 resulted in commercial gas and 6 in commercial oil. Four of the oil discoveries also had commercial gas. No strictly new pools of oil or gas can safely be described as discovered but several scattered oil and gas wells previously drilled have been confirmed as the openers of definite pools; also, various completions closed wide gaps between apparent gas pools already discovered. The proved oil territory of the state was increased about 4850 acres and the proved gas territory about 51,000 acres. The new proved oil reserves should about balance withdrawals and the new gas may represent a substantial increase. Aside from the drilling in four rather lively pools, oil activity was slight because of unfavorable operating conditions and prices. Gas drilling also declined for reasons beyond the control of the operators. The account of operations, as gathered from trade journals and other reporting services, shows that 797 new wells were drilled, providing 119 new oil wells with 2762 bbl. of daily new production; 536 new gas wells with 1,228,501,000 CU. ft. of daily open flow: and 142 dry holes. Also... 76 old wells were drilled to deeper sands, with 71 bbl. and 26,034,000 cu, ft. of added production. On the new wells the oil average was 23.21 bbl. per well per day; and the gas average was 2,270,406 CU. ft. per well per day. On new wells the ratio of dry holes to completions was 17.82 per cent. On deeper drilling the ratio of failures was 21.05 per cent. Production of oil for the year was estimated by the Oil ad Gas Journal as 3,492,000 bbl., as compared with 3,378,000 bbl. in 1941. Production of natural gas for the year is estimated by the author as 220,000,000,000 cu. ft., as compared with the U. S. Bureau of Mines final figures of 207,000,000,000 cu. ft.* in 1941. General State op Industry Leasing of wildcat acreage increased considerably. The total land of all classes under lease may now exceed 5,000,000 acres. Taking into consideration completions, abandonments and corrected figures or estimates, Table I shows cumulative and late annual statistics. New Pools and Extensions Table 2 shows the principal areas of drilling activity during 1942. Various consolidations of territory, hitherto treated as separate pools, have been made. in addition to these active pools, extensive drilling was done in numerous other areas where pool boundaries can hardly be defined. Summary or Exploration Table 3 gives a summary of important wildcat or exploratory wells drilled during

Jan 1, 1943

By David B. Reger

Wildcat drilling for new supplies of gas and the expansion of previously discovered oil and gas pools were the principal petroleum activities in West Virginia .during 1942. Much of the new gas exploration is still uncompleted and still indecisive but various wildcats made substantial extensions to existing pools. Out of 53 wildcats drilled 27 resulted in commercial gas and 6 in commercial oil. Four of the oil discoveries also had commercial gas. No strictly new pools of oil or gas can safely be described as discovered but several scattered oil and gas wells previously drilled have been confirmed as the openers of definite pools; also, various completions closed wide gaps between apparent gas pools already discovered. The proved oil territory of the state was increased about 4850 acres and the proved gas territory about 51,000 acres. The new proved oil reserves should about balance withdrawals and the new gas may represent a substantial increase. Aside from the drilling in four rather lively pools, oil activity was slight because of unfavorable operating conditions and prices. Gas drilling also declined for reasons beyond the control of the operators. The account of operations, as gathered from trade journals and other reporting services, shows that 797 new wells were drilled, providing 119 new oil wells with 2762 bbl. of daily new production; 536 new gas wells with 1,228,501,000 CU. ft. of daily open flow: and 142 dry holes. Also... 76 old wells were drilled to deeper sands, with 71 bbl. and 26,034,000 cu, ft. of added production. On the new wells the oil average was 23.21 bbl. per well per day; and the gas average was 2,270,406 CU. ft. per well per day. On new wells the ratio of dry holes to completions was 17.82 per cent. On deeper drilling the ratio of failures was 21.05 per cent. Production of oil for the year was estimated by the Oil ad Gas Journal as 3,492,000 bbl., as compared with 3,378,000 bbl. in 1941. Production of natural gas for the year is estimated by the author as 220,000,000,000 cu. ft., as compared with the U. S. Bureau of Mines final figures of 207,000,000,000 cu. ft.* in 1941. General State op Industry Leasing of wildcat acreage increased considerably. The total land of all classes under lease may now exceed 5,000,000 acres. Taking into consideration completions, abandonments and corrected figures or estimates, Table I shows cumulative and late annual statistics. New Pools and Extensions Table 2 shows the principal areas of drilling activity during 1942. Various consolidations of territory, hitherto treated as separate pools, have been made. in addition to these active pools, extensive drilling was done in numerous other areas where pool boundaries can hardly be defined. Summary or Exploration Table 3 gives a summary of important wildcat or exploratory wells drilled during

Jan 1, 1943

By G. V. Smith, C. O. Tarr, R. F. Miller

Metallurgists have long recognized that the Fe3C type of carbide is not a stable phase in steel and that, given sufficient time, it will decompose with formation of graphite, at least at temperatures below about 205o°F.l This slow graphitization has never been of much concern to users of hypoeutectoid steels, for in such steels it occurs only during prolonged exposure at elevated temperature. In I935, Kinzel and Moore2 reported complete graphitization of the carbide of a 0. I5 per cent carbon steel that had been in service for about 26,000 hr. at a temperature of about IIOO° to 12oo°F. In discussing this paper, both Mathews and Sauveur reported graphitization of slightly hypereutectoid steels. In an extensive investigation of graphitization of high-purity iron-carbon alloys, Wells1 produced graphite at 7oo°C. (I29o°F.) in an alloy containing as little as 0.13 per cent carbon, and showed that graphite may precipitate either directly from austenite or from decomposition of Fe3C, also that the rate of graphitization tends to increase with increase of temperature, at least up to a certain point, and with the presence of graphite nuclei. Jenkins, Mellor and Jenkinson,3 studying the structural changes in carbon steels ranging from 0.17 to 1.14 per cent carbon during stress-rupture tests at elevated temperature, observed graphite in an aluminum-killed 0.40 per cent carbon steel after fracture in 4340 hr. under a stress of 17,900 lb. per sq. in. at 840°F. and in many of the steels after stress-rupture test at 12oo°F. Unstressed samples of 0.60, 0.86 and I.I4 per cent carbon steels graphitized almost completely in 360 hr. at I200°F., while samples of 0.90 and 1.10 per cent carbon steels were somewhat graphitized, and steels containing 0.24, 0.40 and 0.57 per cent carbon showed no sign of graphite. Their results indicate that graphite precipitates the more readily the higher the carbon content, though this tendency is influenced to some extent by deoxidation practice, and that graphitization is accelerated by plastic deformation. In a recent study of the graphitization of 0.4 and 0.6 per cent carbon steel strip, made by M. A. Hughes,4 it was found that at I2oo°F. graphite appeared after 72 hr. in aluminum-killed but not in silicon-killed steel, and that the rate of graphitization was increased by slow cooling from I6oo°F. and by cold-working prior to annealing. In creep tests of normalized 0.15 per cent carbon steel killed with 2.5 Ib. of aluminum per ton, at the U. S. Steel Corporation laboratory at Kearny, spheroidization and some graphitization were found after 3000 hr. at Iooo°F. under a stress as low as 1500 lb. per sq. inch. .

Jan 1, 1944

By C. O. Tarr, G. V. Smith, R. F. Miller

Metallurgists have long recognized that the Fe3C type of carbide is not a stable phase in steel and that, given sufficient time, it will decompose with formation of graphite, at least at temperatures below about 205o°F.l This slow graphitization has never been of much concern to users of hypoeutectoid steels, for in such steels it occurs only during prolonged exposure at elevated temperature. In I935, Kinzel and Moore2 reported complete graphitization of the carbide of a 0. I5 per cent carbon steel that had been in service for about 26,000 hr. at a temperature of about IIOO° to 12oo°F. In discussing this paper, both Mathews and Sauveur reported graphitization of slightly hypereutectoid steels. In an extensive investigation of graphitization of high-purity iron-carbon alloys, Wells1 produced graphite at 7oo°C. (I29o°F.) in an alloy containing as little as 0.13 per cent carbon, and showed that graphite may precipitate either directly from austenite or from decomposition of Fe3C, also that the rate of graphitization tends to increase with increase of temperature, at least up to a certain point, and with the presence of graphite nuclei. Jenkins, Mellor and Jenkinson,3 studying the structural changes in carbon steels ranging from 0.17 to 1.14 per cent carbon during stress-rupture tests at elevated temperature, observed graphite in an aluminum-killed 0.40 per cent carbon steel after fracture in 4340 hr. under a stress of 17,900 lb. per sq. in. at 840°F. and in many of the steels after stress-rupture test at 12oo°F. Unstressed samples of 0.60, 0.86 and I.I4 per cent carbon steels graphitized almost completely in 360 hr. at I200°F., while samples of 0.90 and 1.10 per cent carbon steels were somewhat graphitized, and steels containing 0.24, 0.40 and 0.57 per cent carbon showed no sign of graphite. Their results indicate that graphite precipitates the more readily the higher the carbon content, though this tendency is influenced to some extent by deoxidation practice, and that graphitization is accelerated by plastic deformation. In a recent study of the graphitization of 0.4 and 0.6 per cent carbon steel strip, made by M. A. Hughes,4 it was found that at I2oo°F. graphite appeared after 72 hr. in aluminum-killed but not in silicon-killed steel, and that the rate of graphitization was increased by slow cooling from I6oo°F. and by cold-working prior to annealing. In creep tests of normalized 0.15 per cent carbon steel killed with 2.5 Ib. of aluminum per ton, at the U. S. Steel Corporation laboratory at Kearny, spheroidization and some graphitization were found after 3000 hr. at Iooo°F. under a stress as low as 1500 lb. per sq. inch. .

Jan 1, 1944

By F. D. Mahone

Much crude oil, as produced from the well, carries varying amounts of water, which may be present as free water in globules sufficiently large to settle out, in time, if the fluid is allowed to stand, or as an emulsion formed by myriads of minute water particles, each surrounded and entrapped by a film of oil through which it cannot break under the action of gravity alone. Such an emulsified mixture of oil and water is commonly termed "cut oil." When such an emulsion is subjected, under proper conditions, to the influence of a high-potential alternating-current field, the minute water particles rupture the enveloping oil films and coalesce into larger water droplets this procedure continuing until all the water is freed into drops of such size that they readily settle out. This action has been photographed by the micro-moving-picture camera; under the microscope, the breaking-up of the emulsion, as described, is seen to be accomplished in a few seconds. The low power requirements of the process, from records of commercial plants, substantiate the theory that the action is that of a multitude of electrical condensers in series, rather than that of a number of conducting paths. The minute water particles serve as the metallic elements, or plates, of the condensers and the separating oil acts as the dielectric. Such surface charges as the particles may have are removed, and the intervening oil is broken, probably electrically by the voltage and mechanically by the attractive force between adjacent oppositely electrified particles. The principle of breaking up an emulsion under the influence of an alternating electric field was discovered by F. G. Cottrell and Buckner Speed, through experiments conducted, at the University of California, which resulted in a plant being installed on the property of the Lucile Oil Co. in the Coalinga field, California, early in 1909. This plant was able to reduce 14-per cent. emulsion to less than Pper cent. with commercial success. Standard Cottrell Apparatus The present standard Cottrell apparatus consists essentially of the electric treater and a settling or trap tank. The treater is a galvanized-iron tank approximately 3 ft. in diameter and 10 ft. high, which con-

Jan 1, 1924

By A. C. Veatch

Jan 1, 1921

By F. X. Meyer

THE United States Smelting Refining and Mining Company maintains an ore-purchasing department for procurement of custom tonnages of milling and smelting ores and concentrates for treatment at its Midvale plant. Arrangements with other companies provide for treatment of Company and custom zinc concentrates. Location of the Midvale plant in the heart of the Western mining country makes it possible to serve shippers from these nine producing states: Arizona, California, Colorado, Idaho, Montana, Nevada, Oregon, Utah, and Washington. Shipments from most of these states travel over main-line railroads, delivery being made at Midvale within a short time after billing of the shipment. Shipments varying in size from a few sacks to carloads can be handled at

Jan 1, 1948

By H. l. Burghoff, A. I. Blank

The state of knowledge bearing on the stability of copper under stress at elevated temperatures is generally known to be in need of revision and extension. The present investigation, dealing with the creep characteristics of a deoxidized copper of low residual phosphorus content, is intended to contribute in some small measure toward this end. The experimental data presented herein have been correlated by methods of evaluation and interpretation familiar to those who are concerned with crecp of metals. In practice it is common, if not requisite, to use structurally stable materials at elevated temperatures. It is frequently desirable, however, to test materials under conditions that produce structural change, in order to determine the extent of such change and its effect on physical properties, thus making it possible to establish accurately the limiting conditions to which such materials may be safely exposed. The creep characteristics of the drawn copper wire of this investigation arc directly associated with its structural instability at elevated temperatures. Complete realization of this fact is essential to the evaluation of its creep resistance under various conditions. Creep results should apply to steady deformation under equilibrium conditions, but these are seldom attained in only one or two thousand hours. It will be shown that steady creep rate for copper at useful stresses does not usually begin until considerably more time has elapsed. A wholly satisfactory substitute or shortcut for extensive creep testing does not appear to be evident in the application of mathematical analyses to limited experimental data. Material A single lot of phosphorized copper wire was drawn down to 0.125-i11. diameter with a final reduction of 84 per cent. After mechanical straightening, a portion of this wire was annealed to an average grain size of 0.013 mm. in a controlled-atmosphere furnace. The composition and initial properties of the copper in these two conditions are listed in Table I. Photomicrographs of the original structure are shown in Fig. I.

Jan 1, 1945