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By J. H. Henderson, J. Naar

The displacement of a wetting fluid from a porous medium by a non-wetting fluid (drainage) is now reasonably well understood. A complete explanation has yet to be found for the analogous case of a wetting fluid being spontaneously imbibed and the non-wetting phase displaced (imbibition). During the displacement of oil or gas by water in a water-wet sand, the porous medium ordinarily imbibes water. The amount of oil recovered, the cost of recovery and the production history seem then to be controlled mainly by pore geometry. The influence of pore geometry is reflected in drainage and imbibition capillary-pressure curves and relative permeability curves. Relative permeability curves for a particular consolidated sand show that at any given saturation the permeability to oil during imbibition is smaller than during drainage. ' Low imbibition permeabilities suggest that the non-wetting phase, oil or gas, is gradually trapped by the advancing water. This paper describes a mathematical image (model) of consolidated porous rock based on the concept of the trapping of the non-wetting phase during the imbibition process. The following items have been derived from the model. 1. A direct relation between the relative permeability characteristics during imbibition and those observed during drainage. 2. A theoretical limit for the fractional amount of oil or gas recoverable by imbibition. 3. An expression for the resistivity index which can be used in connection with the formula for wetting-phase relative permeability to check the consistency of the model. 4. The Iimits of flow performance for a given rock dictated by complete wetting by either oil or water. 5. The factors controlling oil recovery by imbibition in the presence of free gas. The complexity of a porous medium is such that drastic simplifications must be introduced to obtain a model amenable to mathematical treatment. Many parameters have been introduced by others in Iprogressing" from the parallel-capillary model to the randomly interconnected capillary models independently proposed by Wyllie and Gardner3 and Marshall4. To these a further complication must be added since an imbibition model must trap part of the non-wetting phase during imbibition of the wetting phase. Like so many of the previously introduced complications, this fluid-block was introduced to make the model performance fit the observed imbibition flow behavior. THE IMBIBITION MODEL ASSUMPTIONS The following assumptions are common to many two-phase models previously described. 1. The wetting characteristics of the medium are clearly defined. 2. When two fluids co-exist in the medium, the wetting phase will fill the smaller pores and the non-wetting fluid the bigger ones. 3. The pores have a circular cross section. 4. Apparent pore radii are related to the capillary pressure (drainage) by

Jan 1, 1965

Albin, B. R Billings, Mont. '28 Amster, Nathan L 25 Broad St., New York, N. Y. '28 Bache, Jules S 42 Broadway, New York, N. Y. '28 Barrett, C. P 5338 Harper Ave., Chicago, 111. '28 Bayless, William S Russ Bldg., San Francisco, Cal. '28 Bean, Louis, H 60 E. 42nd St., New York, N. Y. '28 Beatty, Ross J Room 604, 6 N. Clark St., Chicago, III. '28 Benwell, Oswald F Hold Mags. '28 Beymer, Albert S., V.P., Keystone National Bank Pittsburgh, Pa. '28 Blumenthal, Hugo 44 Pine St., New York, N. Y. '28 Boettcher. Charles Ideal Cement Bldg., Denver, Colo. '28 Bowlus, Thomas H., Banker, Pres., Allen County State Bank Iola, Ran. '28 Brown, Colvin B Chamber of Commerce, Washington, D. C. '28 Burt, Maxwell Struthers Southern Pines, N. C. '28

Jan 1, 1934

By James F. McDivitt

The mineral industry of today is faced with a number of dilemmas, not the least of which grows out of the series of related facts-world mineral consumption is growing, and is expected to continue to grow; maintaining adequate capacity to meet needs will require very great capital investment over the next decades, investment which must be measured in billions of dollars; much of the new production must come from remote and relatively underdeveloped countries; many of the areas in which such development must take place are not areas in which private capital enters without some trepidation. There are real problems in financing new mineral development-problems which have occupied the thoughts of many in the industry. One group which is currently providing part of the answer, and perhaps pointing the way to further progress in the future, is the World Bank. Loans from the World Bank are arranged usually for countries which are attempting to develop their economies through expanded industrial production. More often than not they are for the development of electric power projects or transportation facilities. Although we consider the mineral industries to be basic factors in industrial development and very important factors in the early stages of development of a country, few of these loans are for mineral development-no more than a half dozen out of a total of well over 300 loans which have been granted to date. Yet the World Bank has played a far more important part in world mineral development than these figures would indicate. The few loans for mineral development which it has made are important, but of considerably greater importance are the secondary effects of many of the non-mineral development loans and some of the special services which the Bank also offers.

Jan 5, 1963

By G. P. Moore

BOLIVIA still remains among the oil countries that have proved oil acreage but no production which is being marketed. No steps have been taken during the past year to provide facilities for transport of Bolivian oil to market nor are any known to be contemplated for 1930. The only active operator to date is the Standard Oil Co. of Bolivia, subsidiary of the Standard Oil Co. of New Jersey. The potential production from completed wells is practically unchanged from the 1928 figure of 6000 bbl. daily. As far as is known, there has been only one completion during the year 1929. This is the Machareti well, which is about 50 km. north of Villa Montes along the road to Charagua. The well is reported at about 250 bbl. daily initial production. The gravity of the oil is not known but is presumed to be about 40" Bé., the average for the region. The Standard Oil Co. of Bolivia has five strings working on various parts of its concession. No new locations have been made definitely. Company Activities There was no change in the situation of American holdings in Bolivia during 1929. The oil rights of an English company, acquired under a special colonization contract with the Bolivian Government, are being negotiated in New York and may mean the entrance of another of the large American oil companies in Bolivia. The Sucre Syndicate sold its holdings to the Standard Oil Co. of Bolivia during the past year. .A local company called the "Aguila Doble" was formed during 1929 to drill a well or wells near the town of Cochabamba on structures mapped by a local geologist. It is reported that the Government is buying about one-fourth of the capital stock of this company for 500,000 Bolivianos (about $180,000). The company has not yet raised sufficieht funds to buy drilling equipment so that no operations have been started. According to the statements published in La Pas, this company has acreage on seven anticlinal structures near Cochabamba. This area lies about 8500 ft. above sea level on the eastern Hank of the Andes Moun-

Jan 1, 1930

By Heinrich Freyn

THE American iron and steel manufacturer finds himself to-clay barely at the threshold of enormous possibilities for practicing rational economy in the use of fuels. The fuel cost is by no means the smallest of items which enter into the cost of manufacture of iron and steel products, but the great wealth of this country in high-grade fuels, together with a protective tariff, has heretofore made fuel economy relatively unimportant. In Germany, the use of raw coal for the purposes of iron and steel manufacture has been all but abandoned and large sums of money, formerly irrevocably wasted, are now being saved. When scanning the literature of this country devoted to the application of gas power, but little information will be found on a subject which, however, is destined to become of considerable importance in the United States, namely, the use of coke-oven gas for the generation of power in gas engines. This lack of information can be traced to the fact that the regenerative by-product coke oven with its large amount of surplus gas is still far from having attained in this country the universal application which it has found in Europe. This statement needs hardy any corroboration other than the evidence of statistical investigations made by E. W. Parker of the United States Geological Survey, according to which only approximately 25 per cent. of the total coke produced in this country in 1912 was made in by-product coke ovens, whereas 75 per cent. was produced in bee-hive ovens. This entailed the enormous loss of over $80,000,000 in non-recovered by-products, such as gas, tar, and ammonia, without considering the substantial loss due to the non-recovery of benzol from the coal. There are two more or less distinct fields of application of the by-product coke oven: one, to furnish as the main product metallurgical coke of specified quality, and surplus coke-oven gas as the by-product, and the other, to carbonize high-volatile coals, and thus produce as the main product large quantities of gas, high in heat value and rich in illuminants, adapted primarily for domestic heating and lighting, while domestic coke becomes the by-product.

Jan 4, 1914

By D. Malhotra, R. M. Hoover

The effect of a surfactant, designated Syntex, on the wetting and spreading of hydrocarbon oil on molybdenite surfaces (faces) has been investigated experimentally through measurements of zeta potentials and factorially designed flotation tests. These studies indicate that Syntex has a positive effect in increasing molybdenite recovery in the rougher flotation circuit at the Climax mill. The analysis of experimental data using DLVO theory shows that the controlling factor in determining the magnitude of the repulsive energy barrier preventing oil from wetting and spreading on the molybdenite faces is the MoS2 zeta potential and the vapor oil droplet size. The role of Syntex in this case seems to be related to the decrease and stabilization of MoS2 zeta potential by Syntex adsorption and also to the emulsifying action of Syntex on vapor oil to provide a more favorable oil particle size.

Jan 1, 1976

By Calvin Pierson, R. S. Dean, E. P. Barrett

MANY studies have been made of the properties of steel produced by adding varying amounts of sponge iron to the charges used in steelmaking furnaces.1-3 The results of these previous studies, however, have failed to disclose a reason for the belief of steelmakers that steel made in this way is definitely different from steel made entirely from scrap or iron melting stock. This paper deals chiefly with the structure of the sponge iron, of the wrought iron made by welding the sponge iron into blooms, and of the steel made by melting the forged and rolled blooms. It is believed that the structure of the final steel is inherited from the ore and that this inherited structure produces marked differences in the properties of the steel and explains the feeling of steelmakers which is based on their experience. Three kinds of sponge iron were used in this investigation: One made from a limonite ore reduced with natural gas, one made from a hematite ore reduced with natural gas, and one made from a magnetite ore reduced with charcoal. The sponge iron made by reduction with natural gas

Jan 1, 1935

By Carll H. Samans, Charles R. Austiuon

It has been known for several years1 that certain alloys of the Konal type, containing commercial cobalt (99.32 per cent Co and 0.42 per cent Ni) and varying amounts of ferrotitanium, exhibit very high tensile strengths at 600°C. However, their proportional limits and yield pints are relatively low. published data' for the alloys quenched in water from 950°C. and then tested at 600°C. are summarized in the upper section of Fig. I. Similar specimens that were aged at 650°C. for 72 hr., after quench and prior to testing at 600°C., gave the result; shown in the: lower section of Fig. I. In the present work the investigation of the properties of these materials has been extended by a study of the tensile deformation characteristics in moderately longtime tests at 600°, 700' and 800°C. after quenching from various solution temperatures. In addition, some metallographic studies have been made to correlate with the deformation tests, and to obtain information on the quasi-binary system cobalt-Fe2Ti. The material, very kindly furnished by the Westinghouse Electric and Manufacturing Co. in the form of hot-swaged rods of 3/16-in. diameter, analyzed as shown in Table 1. The alloys, when originally made up,' were based upon an iron-titanium compound, Fe3Ti, as indicated by the work of

Jan 1, 1941

By Christopher M. St. John, Michael P. Hardy

The paper discusses an approach to geotechnical monitoring of a geological repository constructed for the purpose of isolation of high-level nuclear waste, and describes the conceptual framework for development of an integrated monitoring scheme that is initiated during the earliest phases of site investigation and continues through facility decommissioning. The approach that is proposed recognizes the need to provide specific data to support the licensing process for the repository while avoiding adverse impact upon the system performance. Further, it recognizes present and inherent limitations in both the instrumentation and techniques that night be used within a monitoring scheme.

Jan 1, 1982

By S. P. Barber, G. W. Cutting, V. Alesse, M. Ciriachi

Just what is happening in the preparation and mineral separation stages are questions frequently asked about most processing plants. It is unusual to find the answers readily available in the operating metallurgical data. Knowledge is nominally available from metallurgical balances about the head ore grade, grade and recovery of the concentrates, and the plant tailings. However, the mechanisms which control grade recovery and losses are seldom monitored in such a way as to permit specific analysis: Thus, when questions about the effectiveness of the process are asked, the answers are based frequently upon intuitive professional judgments and local expertise. Detailed investigations of process functions are extensive in terms of manpower, time, and interference with production. An investigation method in which process operating conditions could be provided in a cost effective manner would assist in local process assessment and control. Such a collection of process operating data is defined as a process audit and the development of the necessary techniques forms the subject of this paper. A typical application to a lead-zinc concentrator highlights both the manner of implementing a process and the plant data made available for local use.

Jan 1, 1980

By Hans W. Schreiber, David W. Neuhaus

INTRODUCTION The Sunshine Mining Company's 16-to-1 silver deposit and mine project are located 384 kilometers (240 miles) southeast of Reno and 360 kilometers (225 miles northwest of Las Vegas, near Silver Peak in Esmeralda County, Nevada, at an elevation of about 2,300 meters (7,000 feet). The deposit was being developed, in 1980, with an anticipated mining and milling rate of 150,000 tons per year (500 tons per day). Mining is by underground, blast-hole open stoping with rubber-tire haul-age out of the mine to a straight cyanide plant about 5.5 kilometers (3.5 miles) from the mine. The product is a gold-silver dore which may be further refined at Sunshine's new refinery in Kellogg, Idaho. The cash required for investment was obtained through the sale of $25 million worth of 6 l/2h silver-indexed bonds. Some $15.0 million were directed toward development of the 16-to-1 Mine. These bonds, which were underwritten by Drexel Burnham Lambert of Chicago in April of 1980, are redeemable on or after April 15, 1985 or payable at maturity on April 15, 1995 at the greater of either $1,000 or the market price of 50 ounces of silver. Behre Dolbear acknowledges the kindness of the Sunshine Mining Company (Sunshine) for allowing the presentation of the subject material for this Case Study. APPLICABILITY AS CASE STUDY Reasons for Choosing 16-to-1 The reasons for choosing the 16-to-1 Mine as a case study follow: 1. The project is simple and compact. 2. The mine is small -- thus relevant to other contemplated precious metal operaions in the western states. 3. The areas of risk are readily identifiable. 4. A change to project financing was under consideration. 5. A substantial decline in the price of silver was experienced during development. 6. Behre Dolbear undertook one of the first feasibility studies of The 16-to-1 and thus has some familiarity with the project. Historical Summary The following history serves as a setting: 1. Late 1920s -- minor "production"(?) via shallow pitting. 2. Mid-1930s -- neighboring Nivlok Mine successfully put into production. 3. Late 1950s (?) -- Callahan Mining Company acquired rights and drilled -- results inconclusive; Callahan turned property back to Arthur Baker, who had originally interested Callahan in 16-to-1 on the basis of its similarity with Nivlok Mine.

Jan 1, 1985

By S. P. Singh, V. J. Hucka

There are a number of problems associated with underground coal mining, but the most serious and important are often related to the ground control. The influence of the prevailing geological conditions and features on the stability of underground mining has been outlined in this paper. Special emphasis has been given to the importance of geological techniques in the evaluation of coal mine roof conpetency prior to and during the mining operations. In addition to this, typi- cal ground control problems owing to the geological abnormalities have been depicted by appropriate case histories from coal seams in the State of Utah. The interdependence between longwall design and road- way stability on the one hand and geologic features on the other hand are shown in this study.

Jan 1, 1983

By Howard V. Sears

ArcHodrilling (Arcuate Hole Drilling) of short radius overhead curved holes from within the working level with a new, small-diameter in-the-hole drill produces tangible, assayable chip samples from the entire height of the projected mine level where the hole arcs down immediately in front of the working face. Drilling through the projected level with diamond coring tools produces samples showing the competence of roof and floor strata as well as the geological and economic characteristics of the ore. Hand-portable solid state electronic surveying instrument has been developed to survey the ArcHole and a convenient nomograph plotting record sheet converts survey digital readouts to hole inclination in degrees, to radius of curvature in feet, and to attitude of the plane of curvature from vertical in degrees, all without calculation. The ArcHodrilling system offers a tool with which the exploration geologist can more nearly assess the true potential of old mining properties being reexamined and to reduce the number of surface diamond drill holes needed to secure development data about new ore bodies. It gives the mine geologist an opportunity to secure those data at a fraction of the cost of drilling from the surface. The mining supervisor has a convenient, cheap tool to look ahead to know what he will be mining tomorrow. The mill supervisor has an opportunity to reduce his mineral loss in tailings by being able to anticipate the grade of his mill feed.

Jan 1, 1973

George Ellery Hale, Director of the Mount Wilson Observatory and Foreign Secretary of the National Academy of Sciences, who has been for the last ten years a Correspondent of the Academie des Sciences, Institut de France, has received the unusual honor of election as Associe Etranger, taking the place of Adolph von Baeyer, declared vacant by the Academy. The Foreign Associates are limited to twelve, and the high distinction has been held by only two Americans-Simon Newcomb and Alexander Agassiz. The National Research Council upon the presentation and acceptance of. Dr. Hale's resignation as its Chairman and the election of James R. Angell as his successor, created and bestowed in perpetuity upon Dr. Hale the title of Honorary Chairman in recognition of his services to the National Research Council and to Science and Research by indefatigable efforts that have contributed so largely to the organization of science for the assistance of the Government during the war, and the augmentation of the resources of the United States through the newly intensive cultivation of research in the reconstruction and peace periods that follow.

Jan 8, 1919

By H. A. Guess

For a number of years I have used for the commercial wet assay of lead generally the ammonium molydate, and occa-sionally the ferrocyanide method. These well-known methods need no detailed description here. In the ore-selling and ore-buying establiahments of the West, 90 per cent. of all wet lead-assays are made by one or the other, and at least nine-tenths of this proportion by the molybdate method. A procedure so well-established must have merit; and, in

Jan 1, 1905

By Henry Louis

THE work performed by, the Royal Commission on Mining Subsidence is likely to prove of permanent value, less perhaps for the conclusions it has reached and for the recommendations it has based upon these than for the admirable exposition which it affords of the law concerning mining subsidence and of the legal status of the person who has suffered damage by reason of such subsidence, as also of him whose working has caused the damage. The Commission was appointed by Royal Warrant in the middle of 1925 and delivered its final report in the middle of 1927. The terms of reference to the Commission were as follows: "To consider the operation of the law relating to the support of the surface of the land, and of buildings or works on or under the surface, by underlying or adjacent minerals; to enquire into the extent and gravity of the damage caused by subsidence owing to the extraction of minerals and the incidence of the resulting liability; and to report what steps should be taken, by legislation or otherwise, to remedy, equitably to all persons concerned, any defects or hardships that may be found to arise in existing conditions."

Jan 1, 1929

By O. J. C. Runnals

The intermetallic compounds NpAl2, NpAl3, and NpAl have been prepared, and examined by X-ray diffraction methods. The compounds are isostructural with the corresponding U-Al compounds. NpAl3 is face-centered cubic with a = 7.785A and has the MgCu2 structure. NpAl is simple cubic with a = 4.2624 and has the AuCU3 structure. NpAl4 is body-centered orthorhombic with a = 4.428, b = 6.268, and c = 13.71A. The published description for the atomic positions in UAl, applies also to NpAl4 THE U-Al system has been examined by Gordon and Kaufmann.1 They identified the following intermetallic compounds: UAI2, UAl3, and a third, tentatively identified as UAl5. A structure analysis of the latter compound by Borie2 proved that the formula UAl4 was more consistent with the X-ray data. The crystal structures of UAl2 and UA have been reported by Rundle and Wilson.3 UAl2 was found to be isostructural with MgCu. The atomic positions in the simple cubic UA1, cell were found similar to those in the AuCu3 structure. Three analogous compounds exist in the binary system Np-Al. X-ray data for the compounds NpAl2, NpAl3, and NpAl4 are reported below. The neptunium used in the investigation was supplied through the courtesy of the Argonne National Laboratory as neptunium (V) nitrate. It was stated to have a radioactive content of 99.25 pct Np237. The impurity limits had been established by a spectrographic analysis given in Table I. Any titanium, boron, or bismuth impurity should be effectively removed during the fluorination of NpO2 to NpF4, and sodium, lithium, magnesium or strontium during the alloying procedure. The oxalate ignition technique, described by Westrum for the preparation of finely-divided reactive PuO2, was used.The neptunium (V) nitrate solution, containing 100 mg Np, was evaporated to dryness on oxalic acid crystals. The resulting oxalate was calcined to NpO, by heating in platinum at 650°C for 2 hr. An equimolar mixture of anhydrous hydrogen fluoride and purified hydrogen was passed over the NpO2 for 2 hr at 500°C. According to Fried and Davidson" the above fluorination conditions should produce the purple-black fluoride, NpF3 However, the light-green product showed only NpF4 lines on an X-ray diffraction pattern and contained only an estimated 5 pct of finely dispersed black NpF3 particles on microscopic examination. NpAl3: An intimate mixture of 50 mg of neptunium fluoride and aluminum powder (99.99 pct pure, —28 to $60 mesh) was heated to 900°C in a BeO crucible in vacuum by a tungsten coil for 2 hr, to allow the following reaction to proceed: NPF4 + 7Al + NpAl, + 4AlF. [1] The formation and sublimation of aluminum mono-fluoride in this system was verified from an X-ray diffraction analysis of the sublimate. The diffraction pattern was similar to one obtained in the aluminum reduction of UF4 to UF3,6 showing both Al and AlF3 lines. The resulting alloy was sintered at 1100°C for 1 hr. A powdered specimen of the crystalline product was sealed in a thin-walled quartz capillary for X-ray examination. The photograph was taken on a 14.32 cm General Electric powder diffraction camera, using filtered copper radiation. The films were calibrated in terms of a NaCl standard pattern. The wavelengths used in the calculations were 1.5418A for Cu K and 1.5405A for Cu K The powder diffraction pattern showed that NpAl is simple cubic with a = 4.262 % 0.005A, and is isostructural with UA13 where a = 4.27A1 or a =

Jan 1, 1954

By J. C. Bradley

THE relation of annealing temperature to conductivity of copper wire has been determined.1 Conductivity hard was 98.26 per cent. After a 10-min. heating at 200° C. it was 98.69. By annealing 10 min. at 300° C. a large increase, to 100.93, occurred. Maximum conductivity, 101.15, was attained after a 500° C. anneal; thereafter it decreased to 100.53 after a 950° C. anneal. If copper is gassed the decrease is much more than this. MATERIAL AND METHOD The work was done on high grade electrolytic copper, 99.942 per cent. copper-plus silver, silver 0.0008 per cent. It was hot-rolled to 3 in., then cold drawn to 0.080 in. The wire was cut into 25 5-ft. lengths and numbered 1 to 25 as cut. Four samples were tested hard. The others were wound into 5-in. diameter coils. For the 100° C. heating a coil was put into water, the water brought to boiling, and the wire kept at this temperature for 10 min. For the higher temperatures the coils were placed in envelopes of sheet copper, a little water added, and the envelopes sealed by folding over the edges twice, and hammering them together. This kept the air out very well. The envelope and wire were brought to the desired temperature; this was maintained for 10 min., then the whole was water-quenched.

Jan 1, 1927

By R. G. Schaal

The Magma Mine at Superior, Arizona had an unimpressive beginning as a. worked out silver mine that was purchased in 1910 for $130,000 and then incorporated into the Magma Copper Company which has been continuously mining the deposit since 1915. Copper is the principal metal produced. However, zinc, gold, silver and iron have also contributed to the total metal product. Prior to 1973, the production rate of 1500 tons per day was maintained by hoisting 4 and 5 ton pay-loads at speeds up to 1100 FPM through four small hoisting shafts. The hoists used included 8' and 7' diameter double drum, double clutched doc. and a.c. motor driven geared units built as early as 1917. One old timer that did yoeman's service for many years was an 8' Bollen Pulley with a.c. geared drive that utilized an endless rope system with mechanical grip and release mechanism built into the pulley's throat. Primary power for all of these old production hoists was 25 Hertz. Exploration that was completed in 1967 developed a reserve of 10 Million tons of 5 per cent copper which was sufficient to justify new capital expenditures for enlargement of productive facilities to 3300 tons per day. To reach the new reserves a 22' I.D. concrete lined vertical shaft was sunk to an initial depth of 48431. A 12 ½ diameter adit was bored from the mill side of the mountain to intercept the shaft at a point about 1100' below the collar. This 9200' long adit provides the right-of-way for the mine to mill railway and egress for heavy supplies from rail head as well as a conduit for potable water, electric power, compressed air and mine drainage. Mine operating levels begin 3582' below collar and thereafter have been cut at 100' vertical intervals. Skip loading stations have been installed 4282' and 46821 below collar with an in-shaft skip dump station located 800' below collar. This provides for 4500 tons of storage above the mine to mill train loading station located 1100' below collar. Ore and waste are moved horizontally from stope chutes and drift headings by rail haulage to transfer raises which channel all material to the two mentioned skip loading stations. The 22' diameter shaft crossection is arranged with the two skip compartments on the south side separated from the manway and utility compartments by the cage compartment. The cage counterweight operates in a portion of the southwest quadrant of the shaft. The hoisting plant consists of two conventional Nordberg double drum, single clutch, geared, d.c. motor driven units that are identical except for the drives and automatic controls. The drums are 15' diameter x 105" face with LeBus grooving for 2-1/8" diameter wire rope wound in three layers. Mechanical design emp1o::ed is the same as has been used for the past twenty- five years. One drum is attached to the main shaft by 2 large bolted integral shaft flenge. The loose drum is engaged by a 4-arm positive tooth clutch meshing with radially cut teeth of the clutch ring which is bolted to the drum. The drums are one-piece steel plate weldments having a finished weight of 60 tons each and are mounted upon a 36" diameter shaft that also weighs 60 tons. With the addition of brake rings, clutch, bull gear and rope, the total dead weight adds up to nearly 250 tons that is supported by just three double row spherical roller pillow block bearings. There is no bearing between the drums. All pinion shafts as veil as all head sheave journals are supported in the same type of antifriction bearings.

Jan 1, 1975