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Jan 1, 1922

Jan 1, 1922

By J. B. Knaebel, M. W. Von Bernewitz

OUTSTANDING FACTORS that have largely induced the current great interest in the reopening of old mines and the search for new deposits are the increased relative value of gold, the certainty of a market for it, and the decreased activity and poor profits in other lines of endeavor. It is easy to understand why a miner out of a job and unable to find any other means of livelihood would naturally take to the hills with his pan, pick, and shovel; but never before have inexperienced, would-be prospectors and placer miners materialized from the factories and farms, the haberdasheries, and the oil and gasoline supply stations, in such numbers as the last couple of years have witnessed, except when rich strikes of the proportions of a Klondike have been made. What, may one ask, has occasioned this condition? Unemployment has put these men in a receptive frame of mind, and newspaper and magazine articles have done the rest-- The Gold Miner of Los Angeles (a new weekly), The Mid- Week Pictorial (New York) for Sept. 3, 1932, and Popular Science Monthly for August, 1932, for instance. Even the Saturday Evening Post had an article on a promising part of Colorado. Stories that good wages may be had for the panning in nearly every western state have been featured by daily papers, popular "scientific" magazines, and quasi- technical journals. These tales have been eagerly grasped by thousands of people whose ignorance of mining has only served to increase their enthusiasm.

Jan 1, 1932

By A. F. Banks

INTRODUCTION Selective flocculation-flotation as a method of desliming potash flotation feed has been practiced in the Cominco Ltd. potash plant since November. 1974 when it was installed to replace a less efficient mechanical desliming process. The plant was designed for a consistent feed containing 4.5% insolubles. In practice the quantity and quality of the insoluble material is quite variable. This variability led to serious problems in the deslime circuit and consequently had an adverse effect on sylvite flotation performance. A costly mechanical solution to the problem was being seriously considered when it was drawn to our attention that a selective flocculation-flotation process had been developed. The process was tried first in the laboratory on the Cominco Ltd. ore, then on a pilot basis on 25% of the mill feed and finally full scale. The time from being informed of the process to full scale operation was 18 months. It has since been incorporated into a tailings regrind circuit. The original mine design called for the mining of an 11 foot height up to the top of the three clay seams. These had to be taken as they were a zone of structural weakness. It also assumed that the beds would be uniform with only a few disturbances. Very soon after the initial start up it was found that permanent openings had to take in the layers right up to the upper clay seams and because of the mining process that this material would have to be milled when encountered. The number of disturbed areas in the mine is greater than the design anticipated. In operation the insoluble content of the mill feed varies from 4.5% to 8% plus with the peaks being very short- term to relatively long, from hours to day. In terms of quality, the insolubles in the mining horizon are relatively soft and easily liberated, whereas those above are hard and liberate slowly.

Jan 1, 1979

[JAMES A. BARR Consulting Engineer Mt. Pleasant, Tennessee Washington) D.C. BEHRE DOLBEAR & COMPANY Consulting Mining Engineers and Geologists 11 Broadway New York 4, N. Y. BLANDFORD C. BURGESS Registered Professional Engineer Mining Consultant Monticello, Georgia GLENVILLE A. COLLINS Mining Engineer Uranium examinations Cable "Coins" 210 La Arcada Bldg. Santa Barbara, Calif. COWIN & CO. Mining Engineers and Contractors Consulting Shaft & Slope Sinking Appraisal Mine Development Reports Mine Plant Construction I- 18th St. S. W. B'ham, Ala., Phone 56-5566]

Jan 1, 1952

By A. E. Bellis

The time effect in reheating certain steels below the critical range is very marked. The increased toughness, shock-resisting power, and machinability of steel subjected to a long, high drawing temperature has been thoroughly demonstrated and is of practical importance, particularly in the manufacture of "smokeless" rifle-barrel steel. The time effect in tempering is most important when a maximum drawing effect is desired, in which case the highest physical properties as well as ease of machining are important considerations. These are the conditions in drilling a rifle barrel. A hole, 0.30 in. in diameter and 24 in. long for the Springfield rifle, and 30 in. long for the Russian military rifle, has to be drilled in the heat-treated material. This barrel-drilling operation is probably the most difficult one in rifle manufacture, and anyone who has been connected with rifle manufacture knows how seriously production is affected when "hard" or non-uniform steel for barrels is encountered. The importance of high physical properties (tensile strength, toughness and resilience) in a rifle barrel is obvious. The physical properties of two different lots of barrel steel are given below. The first lot, No. 1, gave serious trouble in the drilling operation; the second gave no trouble at all.

Jan 2, 1918

By AIME AIME

NO MORE SUITABLE time and place than LOS Angeles on Thursday and Friday, July 28 and 29, could have been chosen for the Western Regional Meeting of the~1nstitutk. After attending two clays of technical sessions and enjoying the luncheons and dinners of the meeting, visitors, on the following days, could see the opening ceremonies and events of the Olympic Games, which started on July 30 and continued to Aug. 14. Such d spectacle can be seen only once in a generation in this country.

Jan 1, 1932

By R. M. Scafe

Although hydrogen has been intensively studied in its relation to steel quality, the methods of sampling and determinations are still open to question. It is true that various procedures have been proposed but actually there has not been sufficient agreement to establish a common base from which to work. As a result, it is difficult, to say the least, to correlate the reported results of some of the investigators in this field. The present symposium, premised on methods rather than effects, should prove of considerable value. For the purpose of this discussion two methods of sampling and analysis will be considered. First, sampling of molten steel in the ingot mold by use of an evacuated tube and cylinder using conventional methods of analysis for the gases collected; second, analysis by vacuum extraction involving the use of heating equipment and the determination of the amount of hydrogen evolved from solid steel samples by measurement at reduced pressures. Both methods have been used at Duquesne Steel Works and it is believed that either may be used with considerable benefit if the limitations of each method are recognized. Evacuated Tube and Cylinder Sampling devices for gases in molten steel suggested by various investigators range from very cumbersome and complicated devices to the relatively simple evacuated tube and cylinder used by Soler for deter- mining the CO content of the bath. This latter device was adopted (Fig. I) and modified to meet conditions at Duquesne Works. The principal modifications were in placing the cylinder at the side of the tube and the use of a sleeve on the immersion end of the tube. The first modification was made so that the cylinder could be readily detached and taken to the laboratory; the second, because of the difficulty encountered in obtaining an airtight seal after sampling and because of our practice of re-using the tube. Rigid control of the method of sampling and of the handling of the sample according to plan are of primary importance in hydrogen determinations. This applies to both the sampling of molten steel and the determination of the hydrogen content of cold steel samples. Except for a few preliminary samples taken from spoons, all work on molten steels using the evacuated tube was confined to the sampling and analysis of molten steel during the pour. As mentioned, uniformity of sampling was a basic consideration. As a result, every effort was made to follow definite sampling techniques and procedures. These included control of the depth below the surface from which the sample was taken, the timing between the shutoff and taking of the sample, as well as maintenance and care of the equipment. The distance below the surface at which the sample was taken was readily controlled bv means of a crosspiece and centering device attached to the tube. The steel was poured into the mold to the hot-top junction, the tube was then lowered into the 75

Jan 1, 1945

By H. B. Charmbury, D. R. Mitchell

Everyone in the coal industry from top management to the preparation engineer is vitally interterested in recovering as much salable coal as possible from the run-of-mine product. Coal losses from a preparation plant occur in the solid refuse material being discharged from the plant and in the bleed-off slurry from the water circuit. The refuse is generally hauled from the plant in solid form by trucks, conveyors, or aerial trams to the refuse or culm banks or it may be crushed and transported by hydraulic methods to refuse ponds or dams. The loss of coal in refuse material and the extent of this problem has been covered in another paper. The loss of salable coal in the plant bleed-off slurry is one of the water circuit problems in coal preparation plants. Slurries originate at various places in the processing circuits and are usually disposed of by transportation to waste ponds known as slurry ponds. Even though the combustible material discharged as slurry and refuse from the plant is labeled a loss, the loss must only be considered temporary. There is a tendency at the present time to examine refuse and slurry losses and to reprocess these materials to recover valuable coal.

Jan 1, 1960

Jan 1, 1909

By H. J. Maguire

(Presented by invitation at a meeting of the Spokane Local Section, Feb. 17, 1912.) THOSE familiar with mill-practice understand the work required of an average bucket-elevator, but I wish to call special attention to the wear on the buckets. I have been studying in what manner the life and service of the bucket might be improved, and I feel that an adjustable lip, attachable to each bucket without the aid of rivets, will be of material advantage. For illustration, consider the feed-elevator of a typical mill in the Cur d'Alène district. The ore is carried by water in a launder from the feed-rolls and dumped in the "boot" of the elevator, directly in front of the ascending bucket. Middlings from the return-rolls are similarly handled. Under this condition the bucket not only carries the ore, but also picks it up, and this latter requirement determines the life and service of the bucket. It might be said that it would be better practice to convey the feed to the elevator and dump it directly into the bucket, but at one mill at which this plan was tried the results were disappointing and the rubber belt was badly worn. The wear of the bucket is confined to the lip and the corners which have to pick up the material. When the lip on a corner of a 7- by 12-in. malleable cast-iron bucket is worn down about 3 in., the bucket is of no further value as a carrier and has to be replaced. The worn bucket, containing about three¬quarters by weight of the metal of the original bucket, has a scrap value of about 10 per cent. of that of a new bucket. To the cost of the bucket, however, should be added the time-cost of replacing the old bucket by a new one. This time-cost is considerable when the loss per hour, to cease operating the mill, is about $200. It is out of the question to put lips on a bucket unless the latter was originally fitted with this device. For if it is attempted to fit lips upon buckets not originally provided with

Sep 1, 1912

By David Donoghue

EFFORTS made in the year 1930 and in previous years restricted pro-duction in most of the fields of Texas to a point that was satisfactory, at the beginning of 1931, to the majority of producers and buyers. In the Panhandle, North Texas and West Central Texas districts, a few operators with refinery affiliations or contracts either ignored, or by virtue of injunction suits, did not comply with the Railroad Commission's orders, and there was some oil sold at less than posted prices, which, with the Oklahoma City difficulties, caused the first general price reduction. More could have been done perhaps to help the situation on the Gulf Coast and in the Laredo district, but natural advantages are not readily surrendered.

Jan 1, 1932

By P. E. Cavanagh

SINCE the 1930's' the production of iron ore in Canada has increased from zero to about 15 million tons per year. In the same short period of about 25 years, the steel industry has doubled in output, while the consumption of steel has also doubled. In the 1930's all Canadian steel was made from imported iron ore, whereas today, Canada is exporting considerably more iron ore than she imports. It appears certain that the production of iron ore in Canada will at least double in the near future, and should be over 45 million tons per year at the end of the next 25 years, in 1980. It also appears certain that most of this iron ore will be exported to the United States, with some proportion going to Europe. In this situation, it is logical and proper at the present time for Canadians to consider means of converting some of all of this Canadian iron ore into semi-finished or finished products in Canada.

Jan 6, 1958

By J. A. Faucher

The mining industry has undergone significant technological advances in metallurgical process methods in recent years. The 1000 tpd concentrator of St. Lawrence Colum-bium Metals Corp. portrays the continuing effort made by the industry to achieve economical concentration of new and difficult ores. During the active search for sources of uranium in the early fifties, radioactive minerals were found in the Oka district near Montreal. The compatatively small quantities of uranium which were found occurred in association with widespread columbium (niobium) mineralization which included perovskite, a calcium titanate containing roughly 40% Cb2O5; niocalite, a silicate containing some 20% Cb2O5; and pyrochlore, a calcium niobate containing 45 -70% Cb2O5 as well as fluorine and some water. An idealized formula for one type of pyrochlore is: A typical chemical analysis of pyrochlore is shown in Table I. An important feature of this analysis is the lack of tin, lead, sulphur and P2O5 which conforms with the requirements of most consumers. In general the cerium content varies with sodium content and any increase in Ta2O5 lowers the Cb2O5 content of the concentrate. However, Ta2O5 rarely exceeds 0.5%. The carbonatite host rock of the columbium mineralization has the average mineral composition shown in Table 11. In Table 11, the term "diopside" is used to cover all silicates except mica which is shown separately because of the problems involved with its separation during the concentration process. In some ore zones, small quantities of rare earth minerals, such as monazite are present.

Jan 1, 1964

By H. L. Hollis

The paper read by Mr. George J. Snelus, in 1894, before the Iron and Steel Institute of Great Britain* so fully and ably described the Walrand-Leghisel process that there remains very little to add beyond recording some changes in practice, made since that date, and observed by the writer last summer, at several continental works, and the further fact that the process has now been for some time in successful operation in this country. Briefiy stated, the Walrand-LegBnisel process is an addition to the Bessemer operation, with the object of obtaining quiet and more fluid steel, and consequently sound castings and ingots. This is achieved by adding ferro-silicon at approximately the time of flame-drop in the ordinary Bessemer operation, and making an after-blow. The high calorific power of silicon is well known, and the rapid combustion of it immediately before

Jan 1, 1897

By M. G. Cheney

Careful estimates indicate that during 1942 new discoveries and extensions in West Central Texas added oil reserves slightly in excess of the eight million barrels produced. Drilling activity fell 40 per cent below 1941 and 82 per cent below the normal drilling activity of the late 1920's. Total production for the district continued its downward trend, now being less than % of the 42.7 million barrels peak in 1921. Rapid revival of activity is not probable under existing conditions, as costs of discovery, development and operations on the average probably now exceed current market price for the oil, the latter having remained constant since the spring of I941. Costs have advanced materially since the third quarter of 1941, when reports to the Tariff Commission indicated a margin of profit of 13.3 per barrel. Physical as well as economic conditions are holding back the amount of drilling in this district. The lenticular sands are not suited to 40-acre spacing regulations. There is no surplus of experienced oil-field labor. To reduce costs, much second-hand material is used for all except the deeper wells.. Price controls have retarded movement of used equipment by prescribing maximum prices that arc too low for the better grade materizl, thus making , owners reluctant to sell. On the other hand, buyers are unwilling to pay ceiling prices asked by sellers for poor material. Seventeen new oil fields and five new gas fields were found during 1942. Extensions and deeper 'drilling brought favorable results in eight older fields. The most significant new developments appear to have been in Coleman, Jones, Shackelford and Taylor Counties. A 5800-ft. completion in Wise County brought this county into the producing column for the first time. None of these new discoveries can he rated above one million barrel reserve on the basis of present development. Probably the most important development was discovery of a deeper pay (Gunsight lime) in the Wimberly field of Jones County, which shows promise of producing over an area of about 1000 acres. Jones and Shackelford Counties still lead the district in total annual production. Discovery of the Reddin pool, north central Taylor County, is credited to geochemical methods, making one success out of five or more wildcats based on such methods. Geophysical surveying increased decidedly during 1942 and returns from these studies are expected during coming years. Most of the wildcatting in the district is still based on surface and subsurface geological structural mapping, study of log data as to distribution of prospective producing reservoirs, and drilling in proximity to previous showings of oil and gas. Geological debate continues as to the proper correlation of the 100 to 300 ft. of gray lime that has produced more than 100 million barrels in the Parks, Brecken-ridge, Curry, Eliasville, Ibex, Pioneer and other important fields of this district. Fossils indicate that this limestone is younger than the Atoka beds of Oklahoma. On a structural basis most geologists include this formation with the Bend but a number of paleontologists believe it is more properly classified with the Strawn.

Jan 1, 1943

By M. G. Cheney

Careful estimates indicate that during 1942 new discoveries and extensions in West Central Texas added oil reserves slightly in excess of the eight million barrels produced. Drilling activity fell 40 per cent below 1941 and 82 per cent below the normal drilling activity of the late 1920's. Total production for the district continued its downward trend, now being less than % of the 42.7 million barrels peak in 1921. Rapid revival of activity is not probable under existing conditions, as costs of discovery, development and operations on the average probably now exceed current market price for the oil, the latter having remained constant since the spring of I941. Costs have advanced materially since the third quarter of 1941, when reports to the Tariff Commission indicated a margin of profit of 13.3 per barrel. Physical as well as economic conditions are holding back the amount of drilling in this district. The lenticular sands are not suited to 40-acre spacing regulations. There is no surplus of experienced oil-field labor. To reduce costs, much second-hand material is used for all except the deeper wells.. Price controls have retarded movement of used equipment by prescribing maximum prices that arc too low for the better grade materizl, thus making , owners reluctant to sell. On the other hand, buyers are unwilling to pay ceiling prices asked by sellers for poor material. Seventeen new oil fields and five new gas fields were found during 1942. Extensions and deeper 'drilling brought favorable results in eight older fields. The most significant new developments appear to have been in Coleman, Jones, Shackelford and Taylor Counties. A 5800-ft. completion in Wise County brought this county into the producing column for the first time. None of these new discoveries can he rated above one million barrel reserve on the basis of present development. Probably the most important development was discovery of a deeper pay (Gunsight lime) in the Wimberly field of Jones County, which shows promise of producing over an area of about 1000 acres. Jones and Shackelford Counties still lead the district in total annual production. Discovery of the Reddin pool, north central Taylor County, is credited to geochemical methods, making one success out of five or more wildcats based on such methods. Geophysical surveying increased decidedly during 1942 and returns from these studies are expected during coming years. Most of the wildcatting in the district is still based on surface and subsurface geological structural mapping, study of log data as to distribution of prospective producing reservoirs, and drilling in proximity to previous showings of oil and gas. Geological debate continues as to the proper correlation of the 100 to 300 ft. of gray lime that has produced more than 100 million barrels in the Parks, Brecken-ridge, Curry, Eliasville, Ibex, Pioneer and other important fields of this district. Fossils indicate that this limestone is younger than the Atoka beds of Oklahoma. On a structural basis most geologists include this formation with the Bend but a number of paleontologists believe it is more properly classified with the Strawn.

Jan 1, 1943

By W. M. Raynor

LARGE quantities of "midnight oil" have been consumed by researchers in attempting to develop a process to produce cold ductile zirconium at low cost. The tantalizing facts that zirconium is a bright, silvery, tarnish-proof metal and is 2 1/2 times as abundant in the earth's crust as copper, and thirteen times as plentiful as lead have resulted in much speculation on uses, ranging from automobile radiator grills to kitchen sinks. but unfortunately no low-cost process of producing it has so far been found. In the case of zirconium, we cannot say that "virtue is its own reward" for the principal virtues of the metal, namely, corrosion resistance at ordinary temperatures and ability to absorb gases at high temperature, are the very characteristics that defeat all of the usual recovery methods such as sintering, plating, or direct chemical reduction. The only method giving a pure metal sufficiently low in oxides, nitrides, etc. to be truly cold-malleable is the one developed by Van Arkel and DeBoer in 1925. This process involves decomposition of zirconium tetraiodide in contact with a hot filament and pre

Jan 1, 1947

By J. E. Norton

Production statistics show that during the period of emergence from the depression the coal industry was becoming increasingly cognizant of the economic and competitive necessity for mechanizing. About 1935 many of its leaders were becoming aware also of the alarming scarcity of men properly trained to cope with the new problems of mechanization. In order to get a factual statement of this problem, a special AIME Coal Division Committee was requested to survey the condition. Its investigation disclosed that graduates of mining schools going into coal mining numbered 16 in 1937 and 15 in 1938. With this as a background, Pittsburgh Coal Co. foresaw that a comprehensive program was necessary if it was to enlist the services of trained technical men, who were an indispensable part of a mechanization program. The purpose of this paper is to review the program set up, to comment on the successes and failures and to outline the future course of action. Summer Work An inescapable conclusion from the mechanization statistics was that the opportunities in coal mining were good. Not only was there a void in technical skill to fill from past years, but the accelerating rate of mechanization indicated an increasing demand for technically trained men for the future. The remedy lay primarily in presenting facts con cerning the coal industry to the undergraduate engineers before they made their professional occupational choice. Based on this idea, one of the key points in the program was summer vacation work for the undergraduate, which, through the inducement of summer earnings, brought men into the mines to take a look at the prospects. This was more successful than statistics indicate because the war scrambled badly the orderly working of the program, but it could not obscure the value of a summer work program. A decided advantage was that it gave the company a preview of the graduate. An observation on this part of the program is that it is extremely hard to gauge lower classmen, and we found it wise to give them the benefit of the doubt, as the last two years in college bring about surprisingly rapid development in some men. We could readily single out the men at the opposite ends of the scale of competence. Comprehensive Training Program Having adopted summer work as a means of interesting undergraduates, the Location Weeks Introduction............................... I Underground mining operations............... 27 Coal preparation............................ 24 Inspection—safety, mech., prep............... 31 Mine engineering and survey................. 16 Industrial relations.......................... 12 Operating staff—costs, time study............. 8 Miscellaneous............................... I Total.................................... 120 problem of attracting graduates was met by establishing a training program that covered approximately 120 weeks and

Jan 1, 1949

The Howe Memorial Lecture, in memory of Henry Marion Howe, Past President of the Institute, was authorized in April, 1923, as an annual address to be delivered by invitation under the auspices of the Institute by an individual of recognized and outstanding attainment in the science and practice of iron and steel metallurgy or metallography, chosen by the Board of Directors

Jan 1, 1942