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By Martin F. Milligan

THIS short discussion of the effects of deoxidation on the mechanical properties of cast steels is intended to serve as general introduction to the subject of this afternoon's session. The subject is covered in detail in Mr. Carter's excellent paper. My material has been collected from the works of various investigators, several of whom are present today. For a definition of deoxidation, as applied to steel-furnace melting practice, we can best go to Briggs' book, "The Metallurgy of Steel Castings." Briggs says that deoxidation "includes all the phenomena in the final preparation of steel that would permit it to solidify free from gas cavities and from dissolved oxygen of all kinds." Various practices are used by welters to produce these end results.

Jan 1, 1947

By Thomas E. Bruner

With drilling costs playing a pivotal role in the economics of most mineral exploration programs, there has been a significant effort over the past decade to trim expenditures in this area. One result of these cost-cutting measures has been the substantial shift to use of rotary drills. By the mid-1970's, rotary drilling accounted for six times as much footage as core drilling in exploration work. Among the various rotary drilling techniques, the use of dual-tube drilling for continuous sampling is attracting growing interest. Factors such as drilling speed and cost advantages, coupled with favorable comparisons between chip samples and solid core samples, have helped to spark this interest.

Jan 4, 1979

Discussion of the paper of CLARENCE A. WRIGHT, presented at the St. Louis meeting, October, 1917, and printed in Bulletin No. 130, October, 1917, pp. 1565 to 1591. H. A. WHEELER, St. Louis, Mo.-This paper by Mr. Wright is one of the most thorough and exhaustive studies that has been made of the milling practice in the Joplin district. Mr. Wright spent about two years there, in behalf of the U. S. Bureau of Mines and the Missouri Geological Survey, and this paper, which is the result of his work, will, repay careful reading by any student of ore dressing and is invaluable to an operator in that district.

Jan 1, 1918

By P. E. Palmer, A. H. Daane, C. E. Habermann

Jan 1, 1965

By E. F. Young

The Porter Tunnel will open up 10 million tons of coal for Philadelphia & Reading which can be taken without hoists or pumps.

Jan 3, 1951

By Phyllis A. Lyday

Jan 1, 1985

By Persifor Frazer

The ore property of Mr. Augustus bop is situated about one and a half miles south of the New Windsor Station of the Western Maryland Railroad and is connected with the town of New Windsor by the Liberty and New Windsor Turnpike. It is about forty miles distant from Baltimore, and about seven miles west from the county town of Westminster, and a little more northeast from the celebrated Liberty Copper Mines. (See accompanying Map I and 2.) The property comprises about 140 acres, lying principally

Jan 1, 1881

By Douglas W. Fuerstenau, Kalanadh V. S. Sastry

Based on an analysis of green pellet size distributions and kinetic data on ball growth with taconite concentrates, a ballability index has been developed to quantify ball growth behavior as a function of moisture and bentonite additions. The applicability of the ballability index to such other particulate materials as pulverized limestone and ground magnesite is shown.

Jan 1, 1973

By G. W. Powell

ACCORDING to crank,' the accumulation equations for inter diffusion in a binary system whose molal volume is a function of concentration are

Jan 1, 1965

By John L. Ryon

Experimentation with ammonium nitrate fuel oil mixtures at three under-ground salt mines revealed its excellent applications at those properties. The author relates the present blasting practice used at these mines by the International Salt Co.

Jan 4, 1961

By D. W. Gentry, H. E. Sherer

Determining the age at which to replace a specific piece of mining equipment, and choice of the best possible replacement, is a problem common to nearly all mining operations. This paper examines the data required for intelligent equipment replacement decisions and discusses how to predict future repair cost from historic data, determine the total cost of various replacement alternatives, and evaluate the different replacement alternatives. Various operations research and computer methods were used to develop this easily-used, practical equipment replacement method.

Jan 1, 1984

By Eckley B. Coxe

IN making surveys in the anthracite coal regions of Pennsylvania, the ordinary engineer's chain (50 or 100 feet long) is generally used, both above and below ground. Sometimes, where it is difficult to chain, as, for instance, across a chasm, a wire is stretched from one station to the other, the distance is marked on the wire and its length is then measured with the ordinary chain. Having had occasion lately to make some surveys where it was necessary to determine with great accuracy the position of the land or property line, not

Jan 1, 1874

By D. S. Choi, H. von Schonfeldt, H. D. Dahl

The design of pillars around a longwall panel in which the effect of the adjacent and worked-out panel is taken into consideration is discussed. A mathematical model is used to duplicate field observations such as opening closure and pillar rib movement. The model is then used to predict the effect of changes in mining geometry on the opening stability.

Jan 1, 1976

By D. E. Etter, J. E. Selle

HIGH-PURITY cerium metals, supplied as 99.9 pct pure, by various suppliers, vary widely in melting points and in the shapes of the differential thermal-analysis curves obtained as the samples are heated. A definite correlation is noted between the melting point, amount of premelting, and the number of inclusions present in the material. Briefly, the DTA apparatus, previously de-

Jan 1, 1964

By H. Rush Spedden, Arvid Thunaes

Pilot plant test work in 1942 and 1943 showed that by a combination of desliming, fine-size classification, and Sullivan deck concentration it is possible to recover heavy minerals such as cassiterite at least as fine as 10 microns in size. This appreciable improvement in gravity concentration practice has been substantiated by several full-sized plants.

Jan 8, 1950

By Dale K. Fields

With today's technological advances in mineral processing equipment, there is an increasing demand for accurate system control. This can only come about through representative sampling. The purpose of this paper is to guide in the selection of sampling equipment and outline design parameters for the cutters used in dry and wet sampling without adding redundant mathematical probability formulas. Special attention will also be given to the equipment wed in conjunction with samplers and sampling system, such as feeders, crushers, chutes, launders, and controls.

Jan 1, 1980

1-Coal and Coal Products HOWARD N EAVENSON, Chairman C. T. HAYDEN, Vice-chairman, Bituminous Coal Production CHARLES DORRANCE, Vice-chairman, Anthracite Coal Production HOWARD P. ZELLER, Vice-chairman, Evaluation of Coal for Coke Making W H. FULWEILER, Vice-chairman, Gas and Its Manufacture J. B. MORROW, Vice-chairman, Coal Preparation Bituminous Coal Production C. T. HAYDEN, Chairman R L ADAMS EUGENE MCAULIFFE HAROLD J ROSE WILLIAM H BLAUVELT H E NOLD D. A RUSSELL GEORGE W EVANS JAMES W PAUL CECIL W. SMITH JOHN A GARCIA GEORGE S RICE SAMUEL A TAYLOR H. S GEISMER W F RITTMAN F G TRYON FRANK HAAS J D ROGERS FRANCIS R WADLEIGH CHESTER M LINGLE

Jan 1, 1923

By D. S. Hutton, W. C. Leslie

S. Floreen (1nteumtio)lal Nickel Co.)— One fairly simple way to differentiate between embrittlement due to surface microcracks or due to a dislocation barrier effect might be to load a brittle rock salt crystal in tension to some stress just below the fracture stress and then immerse the loaded crystal in water. If a surface film is retarding plastic flow then one should observe some plastic deformation of the rock salt as

Jan 1, 1962

By Eckley B. Coxe

In making surveys in the anthracite coal regions of Pennsylvania, the ordinary engineer's chain (50 or 100 feet long) is generally used, both above and below ground. Sometimes, where it is difficult to chain, as, for instance, across a chasm, a wire is stretched from one station to the other, the distance is marked on the wire and its length is then measured with the ordinary chain. Having had occasion lately to make some surveys where it was necessary to determine with great accuracy the position of the land or property line, not