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By AIME

A NATIVE son of Salt Lake City. David Douglas Moffat has contributed greatly to both the mineral industries and civic progress in the State of Utah. He was born in 1880 and his whole life bas been intimately associated with mining and milling. His father, one of Utah's pioneer mining men, was superintendent of a mill at Park City. When Moffat was only 18 years of age he went to Philipsburg Mont., where he spent several years as a machinist, and later as master mechanic for the Granite Bi-Metallic Mining Co. He returned to Park City in 1903 as master mechanic and night mill foreman for the Ontario Silver Mining Co. After a few years of varied experience he became, in 1910. general foreman of the Boston Consolidated Will at Garfield, Utah.

Jan 1, 1947

By Robert E. Tally

THE membership of the American Institute of Mining and Metallurgical Engineers is composed largely of technicians, operating engineers, and executives in the mining, metallurgical and petroleum industries. The Institute also has its student, junior and associate membership and its Woman's Auxiliary. Primarily, it is a technical society, devoting itself largely to the encouragement of progress within the industries it represents, and to the discussion and dissemination of facts regarding this progress to its membership. The wisdom of this policy is reflected by the prestige and position which the society has gained, not only .among its members but throughout the entire mining world.

Jan 1, 1932

HOWARD N. EAVENSON, Chairman C. T. HAYDEN, Vice-chairman, Bituminous Coal Production CHARLES DORRANC~ Vice-chairman, Anthracite Coal Production HOWARD P. ZELLW, Vice-chairman, Evaluation of Coal for Coke Making W. H. F'LTLWEILER, Vice- Chairman Gas and Its Manufacture 3. B. MORROW, Vice chairman, Coal Preparation

Jan 1, 1928

Jan 1, 1890

Jan 1, 1954

By B. F. Koch

COPPER reverberatories develop large amounts of exit gases of a temperature in the neighborhood of 2000°F. The gases are not only of a noxious nature but must usually be disposed of at considerable heights above the yard level by a stack. Handling these gases at the temperature mentioned would require rather expensive construction of conveying flues and stack. Moreover, wasting such amounts of heat is certainly most uneconomical. Numerous investigations have indicated that waste heat boilers of the water-tube type are the most practical and economical means for utilizing that heat although the gases are heavily laden with rock dust and copper-bearing slag, which upon cooling form hard deposits on the surfaces of dampers or heat absorbing elements placed in the gas stream. Avoiding Slag and Dust Deposits Based largely on the experience of the paper industry in burning black liquor, a waste heat boiler design was developed a few years ago, providing not only extensive water-wall surfaces for cooling the gases below the fusing point of the slag but also settling out, as far as possible, the solidified particles of slag by creating low gas velocity. Matter carried in a stream of gases or air has a tendency to maintain its original direction upon a change in the direction of the flow of the conveying medium. Reverberatory waste heat boilers installed at Hurley and Morenci endeavored to utilize that tendency for the elimination of slagging particles at predetermined places and before they would strike the tube banks of the boilers. Both installations were successful in minimizing the slagging of boiler tubes and thereby minimizing the need for hand lancing. However, the low draft carried at the up-take of the reverberatory furnaces resulted in a positive pressure in the upper part of the furnace of the waste heat boilers, causing the emission of gases from lancing doors and making more difficult the already unwelcome work of cleaning the boilers by handlancing. Attempting to correct this nuisance as much as possible, the overall height of the Chuquicamata waste heat boilers has been reduced to the minimum considered necessary to obtain proper water circulation in furnace walls. Moreover, it is attempted to solidify slag and dust particles by providing large amounts of water-cooled surfaces before the gas stream reaches super-heater and convection banks of the boilers. The furnaces have been made as deep as an economical and practical arrangement of headers for water

Jan 1, 1952

WILDER D. BANCROFT,* Washington, D. C. (written discussion?).¬In two-phase systems there are three possibilities and Mr. Alexander has only considered two. We may have the first phase the internal one and the second the external one; we may have the first phase the external one and the second phase the internal one; and we may have both phases continuous. This last case occurs when we have a roll of wire fencing standing in the air; the wire is continuous and so is the air. It is quite probable that this case occurs very often in alloys and it it, therefore, important that it should not be overlooked. With gulch,

Jan 3, 1919

By John Birkinbine

Four meetings of the Institute have been held in the anthracite coal-fields of Pennsylvania, and excursioris into the district, in connection with meetings elsewhere, have familiarized our members with

Jan 1, 1892

By Douglas A. Anderson

We have instrumented well-controlled free-face blasts with six- component borehole strain gages, in order to determine the complete strain tensor as a function of time due to explosive loading. The strain tensors have been diagonalized to determine the principal strain time-histories, and further processed to determine the octahedral shear strains as a function of time. Principal strain time-histories, when compared with a computer model, indicate the arrival of various direct and reflected phases. Strong shear strains coincide with the expected arrival time of shear waves. These shear waves are probably instrumental in the fragmentation of confined rock due to explosive loading, and should be incorporated in models of the fragmentation process.

Jan 1, 1984

By Theodore Barry

The task of developing controls in the mining and manufacturing industries to give them a tighter grip on operating costs has afforded this author an interesting vantage point for observing certain practices common to both industries. Of course, each of these industries has problems unique to itself, but all industries have many common problems. After all, every industry is a business and every business is concerned with the task of producing its wares as profitably as possible. While many differences between businesses in different industries are known, the author is convinced through experience that the mining industry has much more in common with the manufacturing industry than is generally acknowledged. Four principal questions come to mind in the comparison of mining with manufacturing: How different are the management control methods in these two worlds? How do both industries go about the task of controlling costs? How does the mining industry compare in terms of the effectiveness of its workers? And perhaps most important, what can the mining industry learn from what the manufacturing industry is doing?

Jan 11, 1962

By C. H. G. Bushell, M. Malnarich

Reagent control in flotation is more an art than a science. Operators vary the amount of re- agents used according to the metallurgy obtained. The amount of collector may be increased, for example, if tailings losses are high and decreased if concentrate grades are low. Often control decisions are based on only one assay, such as the tailings analysis by microscopic or quick assaying techniques. This method of control has given reasonably satisfactory results but is clearly far from perfect. No adjustment in reagent addition can be made until information is received that metallurgy has deteriorated, that is, until the optimum time for adjustment has already passed. The first adjustment probably will be an overcorrection or an undercorrection, and time will be required to establish the best new addition rates. The seriousness of the problem depends on variability of the ore. In ore of continually shifting composition and complexity, mill results will shift back and forth from excessively high concentrate grades and high tailings losses to excessively low concentrate grades and low tailings losses. Economic incentive for improved control also increases with increasing size of mill. Even a small improvement in percentage recovery in a large mill pays for expensive control equipment.

Jul 1, 1956

By S. F. Shaw

THE principles involved in lifting oil in wells flowing naturally are identical with those underlying the flowing of wells by means of the air-gas lift, and information of a dependable nature obtained in the study of the air-lift can be applied to wells with natural flow. A well flowing naturally is one in which the lifting is done by means of the gas-lift, for which the gas is supplied entirely by the formation from which the oil is derived. In air-gas lift operations, there is insufficient gas supplied by the formation to lift the oil to the surface in an efficient manner, therefore additional gas for this purpose must be furnished from an outside source. There may, at times, be conditions obtaining in natural flowing wells different from those in wells flowed by gas-lift, but these differences do not at all conflict with the main principles of gas-lift work. One such condition is met with in wells in which the gas supplied by the formation is in considerable excess of that required to lift the oil to surface; this excess may be so great as to reduce the quantity of oil that can be lifted through the particular diameter of casing or tubing that has been lowered into the well. This same condition can be brought about, however, by supplying a large excess of gas from an outside source to an artificial gas-lift well, and a study of the effects obtained from injecting a large excess into the well can be applied directly to handling wells flowing naturally which have a large excess of gas supplied by the underground reservoir.

Jan 1, 1929

The Library of the above-named Societies is open from 9 A.M. to 9 P.M. on all week-clays, except holidays, from September 1 to June 30, and from 9 A.M. to 6 P.M. during July and August. The Library contains about 55,000 volumes, including sets of technical periodicals and the publications of scientific and technical societies. Members of the Institute, with few exceptions, are forced to spend a portion of their time in localities isolated from sources of information. To these the Library can render valuable service through correspondence; letters requesting information will receive special attention. The Library is prepared to furnish references and copies of articles on mining and metallurgical subjects; to determine the existence of mining-maps, and to furnish general information as to the geology and mineral resources of all countries. All communications should be made as definite as possible so that the information received may be what is desired and not include collateral matter which may not be of interest. The time spent in searching for such collateral matter will be saved, and the information will be sent more promptly and in more usable shape. The members of the Institute can be of service to the Library by forwarding copies of mining-reports, maps privately issued, and similar material, which will be classified, indexed, and made available to other members. Suggestions for additions to the Library, either by purchase or personal solicitation as gifts, will be welcomed. It is hoped that members while in the city will use the Library freely, and assurance is given that most careful service will be rendered to them.

Jan 4, 1913

By C. L. Berrien

Before the present company was formed, in 1916, each group of mines comprising the old organizations made its detailed daily and monthly mine cost records along the lines used before the consolidation; that is, there was no attempt made to standardize and compare the stope costs of all mines. The general cost sheets for all mines, however, were standardized, and cumulative labor cost sheets were compiled in the general superintendent's office. At most of the mines, a daily record or distribution sheet for each working place was kept, showing the number of men, hours of drilling, hours of timbering, hours of tramming, cars of ore, cars of waste, sticks of powder and feet of fuse. This information was kept by each shift boss and entered on the distribution sheet by him or, at some mines, by a tram boss. The superintendent solved his own problems under the direction of the general superintendent, but without coming in touch with other superintendents, either through records or general conferences. Probably 95 per cent. of the stopes were square-set worked by day's pay; there were some back-filling and shrinkage stopes. Many of the development places, such as shaft sinking, station cutting, drifting and raises had always been run by contract. These contracts were given, for no definite period, at so much per linear foot and were measured monthly, or when completed, the men being paid monthly. In some cases, fairness to the employee was not maintained. On the whole, there was no standardization. There were no stope contracts, because of the objections of the Western Federation of Miners to general contracting in the mines. Changes in Stoping Methods Early in 1916, W. B. Daly, then general superintendent, and the author, then assistant general superintendent, visited the Southwest mining districts with the object of finding some improved mining

Jan 1, 1923

By C. L. Berrien

Before the present company was formed, in 1916, each group of mines comprising the old organizations made its detailed daily and monthly mine cost records along the lines used before the consolidation; that is, there was no attempt made to standardize and compare the stope costs of all mines. The general cost sheets for all mines, however, were standardized, and cumulative labor cost sheets were compiled in the general superintendent's office. At most of the mines, a daily record or distribution sheet for each working place was kept, showing the number of men, hours of drilling, hours of timbering, hours of tramming, cars of ore, cars of waste, sticks of powder and feet of fuse. This information was kept by each shift boss and entered on the distribution sheet by him or, at some mines, by a tram boss. The superintendent solved his own problems under the direction of the general superintendent, but without coming in touch with other superintendents, either through records or general conferences. Probably 95 per cent. of the stopes were square-set worked by day's pay; there were some back-filling and shrinkage stopes. Many of the development places, such as shaft sinking, station cutting, drifting and raises had always been run by contract. These contracts were given, for no definite period, at so much per linear foot and were measured monthly, or when completed, the men being paid monthly. In some cases, fairness to the employee was not maintained. On the whole, there was no standardization. There were no stope contracts, because of the objections of the Western Federation of Miners to general contracting in the mines. Changes in Stoping Methods Early in 1916, W. B. Daly, then general superintendent, and the author, then assistant general superintendent, visited the Southwest mining districts with the object of finding some improved mining

Jan 1, 1923

By Duk-Won Park

The PSU/MVS program, one of the computer programs for ventilation network analysis most recently developed at The Pennsylvania State University, was applied to the analysis of modifications to an existing ventilation system for a coal mine located in southern West Virginia. The program is well designed and has diversified capabilities which allow the users to make decisions on the optimum size and number of fans, the location and number of airshafts, and the optimum operational procedures. The mine had 10 working faces, from which the average production rate was about 5900 tons of clean coal per day. Two vane-axial mine fans were used in parallel at a shaft, and both of them operated simultaneously. One additional shaft was in the final construction stage and it would be used in four months to alleviate the load for the existing fans and distribute intake air more evenly. The overall ventilation surveys, including the altimeter pressure survey and the air quantity survey, were carried out in the mine entries, shafts, slopes, and gob areas. Computations were made using the above-mentioned computer program on the present condition and after one additional fan was placed in operation at the new shaft. Also, recommendations were made on the air route and fan blade settings for the most economical and efficient ventilation system. Further studies were carried out to decide the proper period when the third air shaft would be required according to the long-term mining plan. Additional branches were added for the next 4 years of the production plan, and the ventilation conditions were tested at the end of each year. Numerous combinations of blade settings and modifications of air routes were tested. It was recommended that the third air shaft be added at the end of the third year so as not to experience fan stall.

Jan 1, 1982

By N. P. Pinto

Compacting below the recrystallization temperature was studied. Ideal density was attained at 550° to 600°C using 25 tsi. Compacts have strength and hardness higher than cold worked beryllium. The recrystallization temperature of this highly stressed metal is that of cast, cold worked beryllium and appears independent of pressing temperature. THE process metallurgy of beryllium is beset by many difficulties that hinder the production of sound beryllium shapes of controlled properties. Most of these obstacles are traceable directly to the low density, low ductility, and high affinity for oxygen of the metal. Castings are susceptible to cracking and porosity, and controlled grain size is not easily attained, yet is critical to further working. Any process must carefully avoid oxygen pickup. Conventional metallurgical processes, including melting, casting, forging, rolling, and extruding have been treated previously,'" as have the conventional powder metallurgical methods.' More recently, a method has been advanced for producing powder compacts of high density by hot pressing at 1000" to 1100°C, using pressures of 0.25 to 0.5 tons per sq in. (tsi).3 Here, Seybolt and coworkers attained theoretical density of 1.85 grams per cc using pres-sure-temperature combinations of 500 psi-1100°C, 750 psi-1075"C, and higher. The warm pressing of beryllium is a practical method for producing bars of controlled properties and appears to have certain advantages, particularly when high strength and hardness are required. Other investigators have studied the hot pressing of various pure metals, such as copper,"-" gold," iron,10-11 and aluminum." Their results indicate that ideal densities may be attained by compacting at temperatures less than 50 pct of the absolute melt-

Jan 1, 1955

By S. Fisher Morris

The New River coal-field embraces that portion of the Appalachian coal formation which lies on the waters of the New River, principally in Fayette and Raleigh counties, West Virginia, covering a strip of territory about forty miles in length along the line of the Chesapeake and Ohio Railroad from Quinnimont to Kanawha Falls, where the New River empties into the Kanawha, the railroad following the banks of the river the whole distance. (See map.) Between Kanawha Falls and the Valley of the Ohio lies the great Kanawha region, and these two coal-fields possess a greater variety of coal than can be found in any other portion of the country, enabling them to furnish the best fuels for any of the various demands of manufacture or domestic use, the Kanawha region possessing many varieties of gas, hard splint, and cannel coal, and the New River region bituminous and semi-bitnminous, steam and coking coal. The New River, in its westward course towards the Kanawha, has cut its way entirely through the Sera1 conglomerate or No. XII of the Pennsylvania Reports, the Umbral red shales of No. XI appearing at the foot of the mountains at the eastern end of the region at Quinnimont, one of the upper ledges of the Conglomerate forming the summits; while at the western end, at Kanawha Falls, the top of the Conglomerate is nearly down to the level of the river, a portion of the " Lower Productive Measures" forming the greater portion of the mountains. These mountains rise abruptly from the banks of the river to a height of from 800 to 1200 feet, leaving only here and there narrow strips of bottom land, a few acres in extent; and as the measures consist principally of hard sandstones, shales, and conglomerates lying ill a nearly horizontal position, the mountain-sides are very precipitous, with many long and high cliffs, which, with the great height of the mountains, give the country a very rugged appearance. Along the sides of these mountains fronting on the New River and its many tributaries there are exposed the outcroppings of several veins of bituminous and. semi-bituminous coal, varying in thickness from a few inches to over four feet, five of them being workable, or

Jan 1, 1880

The evaluation of suppliers of BOP linings included only magnesitic and periclase compositions. Ford utilizes some dolomitic compositions. Do you care to comment on this subject?

Jan 1, 1972

By AIME AIME

PROBABLY no man has been of greater service to the Institute and has kept more in the background than Henry Krumb. A Vice-President continuously) for the last eleven years, apparently neither his picture nor a biographical sketch ever have adorned these pages and were he forewarned in the present instance he would order us to "forget it." He is a Columbia School of Mines man, Class of '98. He worked underground at Rossland, B. C. for a time, then for a year and a half a. chief engineer of the famous Camp Bird at Ouray, Colo. For three wars he was examining engineer for the Guggenheims and since 1901 has been an independent consulting engineer with experience throughout the Americas.

Jan 1, 1939