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By Edward H. Robie

OF the current Adirondack iron mine development, the Benson Mines operation of the Tones and Laughlin Ore Co. (Jones & Laughlin Steel Corp. wholly owned subsidiary) is the last to go into operation. Following an active construction program in 1943, the mine. concentrator and sintering plant were scheduled to enter production in the fall. This description therefore cannot include any operating data, and details of equipment and flowsheet have not as yet been released.

Jan 1, 1943

By R. E. Sabaski

Total grinding mill system life is dependent upon the original selections and specifications of its components: the mill, its drive, drive motor, motor control, and power system. This paper discusses the complex considerations involved and the critical decisions which must be made by the buyer, the mill manufacturer, and by the gear vendor during the proposal and ordering stages. Interrelations between the mill manufacturer and the gear vendor, application of ACMA standards, how drive standards and specifications are refined through steady-state and computer-simulated torsional analyses are included, along with correlational field testing, as demands for larger sizes challenge the current state of the art.

Jan 1, 1984

By M. Guney, A. R. Bell

In Mindola mine on the Zambian Copperbelt, there is a plan to extend the current production level of 1.2- 1.5 km (3,900-4,900 ft) with five additional production levels. Research work indicated that the present total heat output of 38.6 MW will inevitably increase to 63.2 MW in 25 years. Estimated WE and DB temperatures, representing the total heat generation in stope faces and development headings during these same periods are predicted to increase to 33.8/40.2°C (93/104°F) and 35.3/42.1°C (95/108°F) respectively. It is assessed that the nominal refrigeration capacity needs to be progressively increased to 9,000 M W.

Jan 1, 1984

By C. Gregory Knight

The Pennsylvania Coal Model is a research activity of the College of Earth and Mineral Sciences of the Pennsylvania State University, in association with the Economic Development Council of Northeastern Pennsylvania, and the Southwestern Pennsylvania Regional Planning Commission. In this project, sponsored by the Appalachian Regional Commission and the Pennsylvania Science and Engineering Foundation, data banks and models have been developed to simulate potential coal production and utilization systems in Pennsylvania. Building from a coal system data base for 1974 and mining simulation models, computer optimization models predict potential coal production and transportation for alternative future demand scenarios. The model allows derivation of costs of various coal supply systems under specific economic, transportation, and environmental constraints. The model also provides insight into such impacts of coal production as employment, land use, and environmental quality.

Jan 1, 1977

SAN FRANCISCO LOCAL SECTION Executive Committee G. HOWELL CLEVENGER, Chairman C. W. MERRILL, Pace-Chairman JAMES C. RAY, Secretary-Treasurer, 1235 Webster St., Palo Alto, Cal. F. W. BRADLEY ANDREW C. LAWSON Meets on the second Tuesday of each month Farewell Dinner to H. Foster Bain H. Foster Bain, Who has gone to London to assume the editorship of the Mining Magazine, was tendered a farewell dinner by the San Francisco Sections of the American Institute of Mining Engineers, the Mining and Metallurgical Society of America, and the Engineers' Club, on the evening of Mar. 9, 1915, at the Hotel Bellevue, San Francisco, 85 members being present. George H. Clevenger acted as Toastmaster and the following toasts were responded to: Bain and the Mining Industry, E. H. Benjamin. Bain, the Geologist, A. C. Lawson. Bain, the Man, F. W. Bradley. Bain, the Friend, C. W. Merrill. Bain, the Schoolboy, C.. F. Tolman. The Frontispiece and Flow sheet from the souvenir program, designed by James C. Ray, Secretary of the Section, are reproduced herewith.

Jan 5, 1915

By D. B. McWhorter, J. D. Nelson

Conventional analyses of seepage through saturated media do not apply when tailings impoundments are located above a partially saturated zone. Three stages of seepage are identified and methods for estimating the seepage rates and duration of each stage, based upon flow in partially saturated and saturated porous media, are demonstrated. The effectiveness of earthen liners is discussed and procedures for estimating the required properties of the porous media are provided.

Jan 1, 1981

By Kenneth Seaver

Discussion of the paper of KENNETH SEAVER presented at the San Francisco meeting, September, 1915, and printed in Bulletin No. 105, September, 1915, pp. 1913 .to 1927. J. W. RICHARDS, South Bethlehem, Pa.-This paper concerns a very large industry, and an important detail in that industry. Within sight of where I live in Bethlehem, Pa., are coke works in which $2,500,000 was lost by the use of improper bricks in the coke ovens. This was the fundamental reason of the failure of the plant. The old ovens have all been torn out and replaced by new ovens built of proper bricks. This may emphasize the commercial importance of this subject. When speaking about coke-oven brick, the first thing that comes to my mind is how important it would he if it were possible to. get a brick of better heat conductivity. The heat for coking coal has to go through the thickness of the brick. The silica brick used has low heat conductivity as compared with some other refractories; magnesite brick probably has four times its heat conductivity. The coke oven needs bricks of high heat conductivity. Any process which would increase the heat conductivity of silica brick would undoubtedly shorten the coking process.

Jan 12, 1915

Steel Tape The new Lufkin Royal Ni-Clad steel tape, made in 25, 50, 75, and 100-ft sizes, is stated to cost less than any other steel tape on the market. Figures and graduations are an integral part of the steel and the nickel plated surface is rust and corrosion resistant. Circle No. 1 Lift A manually operated and propelled hydraulic lift marketed by Century Products Co. weighs only [ ] 150 lb, but the 23x24 in. platform will raise 1000 lb from floor level to 4 ft height. Circle No. 2 Scintillation Counter The Scintillator from Precision Radiation Instruments, stated to have 100 times the sensitivity of the Geiger counter, is suitable for prospecting and may be operated from plane or moving vehicle. The instrument is contained in a 2-lb probe and the belt mounted battery box weighs less than 4 lb. Circle No. 3 Generators Wincharger Corp. announces development of a Speedy-Shift wheel-barrow base type attachment for model 700, 1800 and 5000 engine-generator sets. Portability of the engine-generator sets themselves has been improved by belted construction for higher operating speed and maximum weight reduction. Circle No. 4

Jan 1, 1952

Jan 1, 1917

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Jan 1, 1942

By J. de la Vergne, L. O. Cooper

The hydrostatic steel mine shaft liner (HSL) Provides a permanent wall lining for drilled shafts. It is watertight and suitable for bad ground conditions. After a shaft has been drilled to its full depth, the HSL is lowered into it and secured in place with cement grout. The liner consists of a cylindrical steel shell usually reinforced with exterior stiffening rings. The shell is basically designed for compressive strength and the rings are provided to give the shell added resistance to buckling. There are no published standards for the correct procedures to design an HSL. This paper gives a method that appears logical. A design solution can be complex with increased opportunity for error. This paper presents simple formulas to produce sufficient accuracy for construction design. Two new concepts are presented, referred to as transition pressure and critical pressure. An example demonstrates use of the formulas and concepts presented. To facilitate comprehension and use of the formulas, Greek letters are avoided and most of the English alphabet symbols used refer by association to their definitions. An appendix shows derivation of the formulas.

Jan 1, 1984

It was a pleasure listening to this paper. Gary Works' problems were a lot more extensive than the trunnion bearing problems encountered at the Weirton Steel Division. In our two-vessel shop bearing failures are critical in that with a bearing failure on an operating vessel and the second vessel under rebuild, we are down until the vessel rebuild is completed or the bearing is repaired. The first bearing problem at Weirton occurred after we had been operating three years. The failure occurred during the 8th heat following "bum-in" of the vessel. Immediate steps were taken to change the damaged float bearing without an extensive search for the reason the bearing failed. Once the campaign was run out the bearings were inspected and found to be damaged. Field checks revealed that the bearing pedestals were not properly located and as a result the freedom of the float bearing was restricted. The trunnion pin end to end dimension had decreased due to distortion and deflection in the trunnion ring. These dimensions were within tolerances. The damage to our bearing was similar to that in the exhibits from U.S. Steel-Gary Works. Steps taken to correct what was found in the field checks were as follows: 1. The pedestals were relocated to center the bearings. 2. 4" diameter pins were installed to locate the housing in the pedestals. 3. The bearing pedestals were opened up to allow the bearing housing to move slightly in the pedestal. 4. Lubrication fittings for greasing between the bearing housing and the pedestal were installed.

Jan 1, 1972

By Fred Hellmann

IT IS hardly to be doubted that the opportunity within the grasp of the mine manager for beneficent and helpful action in relation to young engineers seeking employment under him is very broad and very big. It is my experience that a manager usually has a strong inclination to help along those who have chosen the career which he has selected for himself, and to aid them and support them as their steps tread the paths which his own feet have previously followed. He has .a strong sympathy for them in their efforts, he almost yearns to shield them from the mistakes into which he himself fell, and to assist them to avoid the pit-falls of which he knows by bitter experience. Yes, this tendency and inclination is strongly developed in most managers, and they would welcome the opportunity of extending the helping hand, if they knew precisely how best this could be done.

Jan 5, 1923

By John C. Smock

While I was engaged in the preparation of a catalogue or list of mineral localities of the United States, east of the one hundredth meridian, for the U. S. Geological Survey, the thought occurred to me that an arrangement or classification of the iron-ore districts of the eastern part of our country according to their geological horizons would be an interesting topic for a paper, and would furnish a basis upon which to arrange many facts brought out by the constant development of our iron-mining districts. Our text-books of mineralogy, geology, and ore-deposits describe the iron-ores and the

Jan 1, 1884

Jan 1, 1934

By Robert H. Richards

Very little has been published recently on this subject in the mining journals or proceedings of societies. The attention of experts has been diverted perhaps by the demands for pan amalgamation of refractory ores. Yet free milling ores occur in many localities, and it may be interesting to have on record some data as to details of running a small test-mill, especially as details of results do not seem to be accessible to stndents and investigators. Küstel, in 1863, under battery amalgamation, dismisses the subject by stating that "amalgamation on copper-plated platforms, troughs, and other copper fixings" is " very imperfect, and mostly abandoned." J. Arthur Phillips says, in 1867, under placer mining : " A well-amalgamated copper plate is considered as effective for

Jan 1, 1880

By Franc R. Joubin, D. H. James

Uranium exploration in the North Shore area of Lake Huron goes back to 1847 when J. L. LeConte, a distinguished American geologist, identified a pitchblende-like mineral which he called coracite from specimens sent from a locality north of Sault Ste. Marie. In 1948 a search for the LeConte occurrence resulted in discovery of the Camray field, some 70 miles north of Sault Ste. Marie. Prospecting the Camray field yielded about 30 pitchblende occurrences spread over approximately 200 sq miles. Almost without exception these discoveries consisted of narrow, short, pitchblende-filled fractures, within or along the contacts of diabase dykes cutting pre-Cambrian Archean granite and gneiss. Eight discoveries were diamond drilled and three were explored underground, but none proved to be of economic value. Uranium prospecting at this time spread far afield, and it was in 1949 that radioactive conglomerate was discovered in Long Township of the Algoma district midway between and 90 miles from Sault Ste. Marie and Sudbury. F. Joubin examined this discovery at that time but could not interest capital in its development.

Jun 1, 1956

Jan 1, 1935

Jan 1, 1894

By A. A. Venghiattis

This paper is discussed not because of its intrinsic value but because it has been related by its authors to the oilwell gun perforators. It is well known that conditions almost ever present in oilwell perforations are the overburden and the presence of the casing. Because of the lack of information in the paper on the dimensions or confinement of the target rocks, one is led to guess that they were not confined at all and, particularly, that no steel front plates were used on the impact face of the rocks to materialize the presence of the cemented casing. This situation, plus the fact that small steel balls have been used as projectiles instead of actual bullets, makes the whole thing unapplicable to oilwell perforation. When shooting is performed against target rocks confined (as shown on Fig. 1) in such a way as to give a fair image of the overburden applied to the formation to be perforated, as well as of the cemented casing, the following are found. 1. There is no cratering worthy of mention, even with bullets having 10 times higher impact energy per unit projected area than the steel balls mentioned in the article. This has been confirmed with sandstone as well as with other rocks (granite, limestone and chalk). See Figs. 2 and 3. 2. Penetrations vary closely as the logarithm of the impact velocity. On this matter I have established the relation