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New Products Equipment

Jan 7, 1953

By Charles P. Williams

THE successful production of zinc white or oxide on a commercial scale in this country dates from the issue of the patent of Samuel Wetherill, for the preparation of the material (November, 1855), and

Jan 1, 1877

By R. A. Wood, R. I. Jaffee, H. R. Ogden, D. N. Williams

CERTAIN titanium alloys when quenched to retain the 0 phase at room temperature show extensive transformation of 0 to martensitic a during deformation. Alloys of this type are usually characterized by low tensile yield strength, a large spread between yield strength and ultimate strength, and high uniform elongation. A previous investigation of this phenomenon concluded that the principal contribution of the martensitic transformation was to increase the amount of deformation prior to fail-

Jan 1, 1964

By L. P. Bayvel

The method of spectral transparency was investigated. A device for measuring particle sizes based on this method was developed, tested and applied. The device affords measurements of particle size distribution in the range from 0.1 to 4 µm. It proved possible to measure sizes not only of spherical particles but also of non- spherical ones. The spectral range in which it is necessary to determine transparency for particle size measurements was found.

Jan 1, 1980

By H. H. Pentz

THIS paper gives the derivation of a practical formula for the calcu-lation of slopes in seismic reflection prospecting. The derived formula is an approximation and can be used where the slope of the reflecting horizon is less than 250 ft. per 1000 and the depth to the reflecting horizon is greater than 2500 ft. The slope of sediments in oil regions is generally considerably less than 250 ft. per 1000. This is particularly true of the Gulf Coast, with the exception of the salt domes, which usually have the sediments at a greater slope than 250 ft. per 1000.

Jan 1, 1937

By E. V. Given

Designing a tailing dam is a major step toward fully integrated mill operation. In the case of large concentrators considerable planning is necessary, and the site of the tailing disposal area may very well dictate the location of the concentrator itself. Before a suitable location can be selected several pertinent factors should be investigated: estimated life expectancy of the mine and, if possible, approximate total tonnage; knowledge of daily mill capacity; and the possibility of future mill expansion. In addition, the area should be able to store tailing for many years and, from a cost and maintenance stand- point, gravity flow will probably be desired.

Jan 7, 1959

By J. Clayton Nichols

The principal mines of this region are 7 miles SE. from Gusa, and about 4 miles in a direct line from the seacoast. Gusa is a small town on the north coast of Mindanao, 4 miles east from Cagayan, the capital of the province of Misamis. The mines are reached by steep, narrow trails over ridges varying in altitude from 1100 to 1600 feet above sealevel. The whole region is covered with a thick growth of tall grass, except a few spots on the sides of some of the hills, where there are patches of timber and jungle.

Jan 1, 1902

THE shipments of high-grade manganese ore, con-taining 35 per cent or more of manganese, from the mines in the United States in 1926 were slightly less than half as large as similar shipments in 1925, accord-ing to the United States Bureau of Mines, Department of Commerce. The shipments in 1926 by 45 producers amounted to 46,258 long tons as compared with 98,324 long tons by 42 producers in 1925. This decrease was due to the falling off of the shipments from Montana. The domestic production of metallurgical ore in 1926 was 26,530 tons; that of chemical ore, 19,728 tons. Montana was the largest shipper with 5713 tons of metallurgical ore and 17,904 tons of chemical ore. The largest individual shipper of metallurgical ore was the Crescent Mine in the Olympic Mountain Region, Clallam Co., Washington, from which the shipments for the year were 3162 tons. The mine was operated by lessees and reverted to the owners in July, and thereafter to the close of the year no .ore was shipped.

Jan 6, 1927

By James Boyd

All mining and milling enterprises must be based on adequate ore reserves. Reserves must be established by physical exploration, and the orebody should be of sufficient size and grade to insure recovery of capital invested in mine purchase, development, and mill construction and to provide a reasonable profit. Determination of these economic factors is so complicated, and present costs of mine development and construction so great, that analysis can be made only by competent persons qualified by experience in this field. What rate for maximum efficiency? Unfortunately, even today mills are built before deposits have been adequately outlined, and there are rusting monuments to such folly in nearly every mining region. Also there is a tendency to be guided by the philosophy that "if a little is good, a lot is better," which leads to the conclusion that mining at a given rate and making so much per ton will yield a profit of so many dollars per day. Consequently, why not build a mill to treat twice as much per day and make twice as much money?

Jun 1, 1956

Jan 1, 1920

Jan 1, 1920

By W. O. Hotchkiss

IN CONSIDERING the question of mining methods the possible rate of production deserves much more attention than it often receives. Hoover's theorem that, in order to show the greatest profit, an orebody should be worked out in the shortest practicable time, should be better known. The author recently' obtained detailed statements of costs from iron-mine superintendents of the Lake Superior district. In discussing these, the effect of rate of mining on cost of production was considered and detailed estimates were made. The methods by which these estimates were made and the way in which they were presented are here described to illustrate the importance of this factor in mining operations. The saving due to lower costs is not the only factor that should be considered. The greater profit per ton is of much importance but of equal importance are the greater profit per ton that will be made on a greater number of tons per year, and the fact that the total profit will be received in a shorter; period. This last makes a great difference in the present value of a property, by shortening the period of discount on future profits. Another item of importance to those operating a number of mines is that the tonnage needed to supply the market can be obtained most profitably by operating the smallest number of mines that will supply the amount required when each is worked to maximum capacity. In the Lake Superior iron district there are many grades of ore, and the requirements for each are known. If the demand for a certain grade can be supplied from mines now operating, the development and mining of a new orebody of the same grade must result in lower rates of production and lower profits to all mines producing this grade. If a company is mining the same grade of ore from three mines when it can supply its needs by operating only two, by operating only two it can obtain the greatest profit. Royalty rates, lease terms, and other considerations modify this general statement, but if all three properties

Jan 5, 1922

By S. T. Sorrell

To obtain a negative determination for prime farmlands in its approved lignite surface mine permit application, Phillips Coal Co. conducted a soils mapping effort and a historic land use survey. In addressing the justification for topsoil substitute materials, the company relied on results of a geochemical evaluation to demonstrate improved drainage, trafficability, and fertility. It also relied on results of field test plots. Post-mining land use was determined through the use of overlay maps considering existing land use, vegetation, and historic prime farmland. The reclamation plan incorporated these elements plus indicator species, existing vegetation, and wildlife needs.

Jan 1, 1985

By A. M. Gaudin

IT is only in recent years that substantial progress has been made in developing a physico-chemical picture of the solid state. The molecular concept, so useful in dealing with gases, was naturally carried over to the field of crystalline solids; it has resulted in the firm implanting of erroneous concepts that only now are being eradicated successfully. Two simply written and effective books on the subject are Crystal Chemistry by Stillwell1 and An Introduction to Crystal Chemistry by Evans.' A more complete treatment of the subject is available in a book by Wells.' The monograph by Hückel4 also touches on a subject most easily perceived by reference to the brief introduction by Bragg,5 that master of the field. These texts make it clear that while some solids are built of molecules, many are built of ions, others of atoms connected in the form of giant molecules, and still others of cations and electrons. The various lattices in which these entities are systematically arranged, the joint use of several of these entities, and the transitional character of some of the bonds make for the great variety of crystalline solids. The purpose of this paper is to point out a most important corollary of present views on the structure of solids. In this connection the classification of solids in Table I is helpful. Atomic crystals are those formed by the noble gases, e.g., helium and argon. They are soft, sublime at very low temperature, of very low specific gravities, and not encountered in ores. Molecular crystals are uncommon among inorganic materials, common among organic materials. Typical examples from both inorganic and organic fields are sulphur, iodine, naphthalene, benzene, and carbon tetrachloride. These crystals are soft and have low specific gravities; where the molecules are small, the sublimation temperature is low. Filament and sheet crystals are rare. They are typified by elemental selenium and elemental arsenic, respectively. Graphite and molybdenite come near being sheet crystals. These crystals are soft in some directions, tough in others, sublime at various temperatures. Diamantine crystals, typified by diamond, are very few in number, stable at high temperatures, and extremely hard. Ionic crystals are common. Most salts, acids, and alkalies belong in the two classes of ionic crystals; examples are rock salt, fluorite, calcite, and angle-site. The salts, acids, and alkalies that do not belong in these classes are more properly regarded as transitional between ionic crystals, framework crystals, and diamantine crystals, e.g., ice and quartz. Fiber crystals are relatively uncommon mineral-ogically speaking, but common in the fields of living processes. Examples are asbestos, silk, cellulose, and wool. Many fiber crystals are so little known even now that their crystallinity may be doubted. Layer crystals, among the more interesting and useful of solids, include a wide variety of substances

Jan 1, 1956

By AIME AIME

NINETEEN states have on their statutes laws requiring engineers practicing within their borders to be licensed sixteen other states have such laws under consideration. While mining engineers are not specifically referred to in every case, they are referred to by implication. In only a few states have mining engineers taken any active interest in this subject, either in support or in opposition, yet it is a matter of very grave importance to them. By some it is thought that it is now too late to take any active steps toward preventing or repealing a type of legislation for which there appears to be a growing demand from some source. And it is further thought that the best course for those who are interested is to endeavor to guide legislation so that the remaining states may enact laws containing as few objectionable features as possible.

Jan 1, 1921

By A. J. Teplitz, T. Bardeen

In the course of an investigation of lost circulation, a new tool has been developed which gives a qualitative measure of the relative velocity between the fluid column in the borehole and the tool. The position of a diaphragm in the side wall of the instrument depends on the flow through the device. This position is established by using the conductive borehole fluid in a potentiometric circuit. The instrument has high sensitivity and can detect changes in velocity as low as. 5 ft/min. Lost circulation mud additives do not interfere with the satisfactory performance of the tool. In a number of circulation losses of the pressure induced type, the instrument has shown that the losses were confined to extremely narrow zones (less than I ft), indicating that such ruptures occur in a more or less horizontal rather than vertical plane as has often been assumed. This pinpointing of the zone of loss is important in remedial procedures since it allows the treatment to be applied directly to the point of loss rather than to the entire open hole. The device can also be employed for indicating points of entry of water in producing wells. INTRODUCTION The need for an improved means of locating the positions of lost returns zones became evident during an investigation of lost circulation difficulties in the Gulf Coast area.1 With instrumentation available at the time, it had been learned that, contrary to common belief, the position of the thief zone responsible for a given loss seldom coincided with the point of bit penetration at the time the loss was encountered. In the majority of cases, the losses were found to be occurring at some distance removed from the bottom of the hole —sometimes as much as a few thousand feet. This information, along with other observations made during the investigation, led to improved techniques' for dealing with lost circulation problems. Highlighted, however, among the results of this work and of similar studies subsequently conducted in drilling operations in other parts of the country, was the indication that a considerable portion of the difficulty and expense involved in treating prolonged circulation losses is due to the unsystematic application of remedial measures to one or more apertures of unknown position. Basis of Tests It is worth considering that if the troublesome formation could somehow be transported to the surface where it could be directly observed, there would likely be little difficulty in readily effecting a seal. Although this is a decided oversimplification of the situation, it does appear that the chief obstacles to similar ease of handling of a lost circulation zone in a well are lack of visibility and of ready accessibility. The latter handicap is overcome to a considerable extent by placement techniques already in use, and other procedures now in the process of development are expected to offer further improvement. But in the matter of visual observation, the technique to be presently described appears to afford a quite satisfactory substitute.

Jan 1, 1957

Jan 1, 1940

Jan 1, 1942

Jan 1, 1940

Jan 1, 1914