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By P. T. Craddock, H. V. Paliwal, L. K. Gurjar

The Indian cultural heritage of mining, smelting and the use of minerals and metals dates back to ancient times. Although the exact date of the commencement of such activities in India is not certain, Indians are known to have been familiar with gold, silver, copper, tin and lead and to a lesser extent with iron at least since the Vedic period (Table 1).

Jan 1, 1999

By Brian FitzPatrick, Michael J. Weaver

Everyone has a role in site safety, even consultants. This paper presents a summary of how a geotechnical and environmental consulting firm, with field staff on construction and subsurface explorations sites, engaged their staff and leveraged relationships with contractors to assess the construction related risks to which its staff members are exposed. These findings were then integrated into their technical training materials for both new staff and those needing a refresher, so that safety is discussed at the same time as the technical work and not treated as a separate topic. The paper outlines the process of identifying and evaluating the construction related risks that staff members face and presents examples of how the consultant can engage contractors in the process. By doing this, knowledge can be shared and there is a better mutual understanding of the risks associated with common construction and exploration related field tasks. The work resulted in an increase in staff engagement in safety, a better understanding of the true risks that staff face in the field, better relationships with contractors, and lower safety metrics. HISTORY At Haley & Aldrich, Inc., we renewed our safety journey in May 2012. Like many others, we had concerns over injuries our staff experienced in the three previous years, and a potentially significant utility strike we experienced while excavating a trench. In 2009, 2010 and 2011 we experienced an increase in recordable injuries, including two significant injuries, which caused our Experience Modification Rate (EMR) (see note below), Total Recordable Incident Rate (TRIR), and Days Away-Restricted, and Transferred Rate (DART) to rise significantly. See Fig. 1 for details. This caused us to step back and review our approach to safety, and our “safety culture”. The rise in reportable incidents and injuries also corresponded to the beginning of a growth period for the company.

Jan 1, 2019

In the absence of. J. B. Marks, President, the meeting was called to order by George B. Pryde, Past President. After organization, the meeting was turned over to W. J. Reid, Vice-President for Utah. A moving picture, "The Story of Dynamite," was shown by the courtesy of the E. I. DuPont de Nemours Company. This provoked a great deal of discussion and many questions were asked A. E. Anderson, who described the paper. John M. Jennings read a description of the United States Fuel Company's new Hiawatha tipple, after which the meeting adjourned to Hiawatha for lunch and a visit to the tipple and outside workings of the Hiawatha mine. Thursday, August 27, 1925 Meeting called to order at 9:30 by Vice-President W. J. Reid. Papers were read on the subject of "Mechanical Loading," by A. W. Dickinson, 0. G. Sharrer, and the paper of Glen A. Knox was read by the Secretary. General Superintendent George A. Murphy, of the Spring Canyon Coal Company, read a description of their newly completed tipple. The meeting then adjourned for Spring Canyon where lunch was served, and the afternoon spent in viewing the new. tipple. At 8:00 p. m., D. Harrington read a paper on "Rock Dusting," L. C. Clare read a paper on "Mudite's Relation to Nature," and at 11 p. m. the meeting adjourned. Friday, August 28, 1925 Meeting called to order at 9:30 a. m. by Vice-President W. J. Reid. The discussion of preceding papers continued. Paper by Joseph Harrington on "Domestic Fuel Stokers" was read by the Secretary. The expected paper by Mayne Read was not presented as Mr. Read was unable to get to Price on account of railroad conditions. The papers on the "Theory of Spontaneous Combustion," by C. P. Crawford, were also omitted through an error of the Secretary, and particular attention is called to the publication of these two articles. The new tipple of the Columbia Steel Company was described by T. C. Harvey, after which the meeting adjourned for Columbia, where luncheon was served and the nine visited. After the visit to Columbia, the delegates were taken to the Sunnyside mine of the Utah Fuel Company, where an hour was spent. Upon motion, unanimously adopted, the Secretary was instructed to express the sincere appreciation of the delegates to the Price Chamber of Commerce, the Civic Association, the Price News-Advocate, Harry Keene, Harry Duberstein, John M. Jennings, Chairman of the Committee of Arrangements, and Geo. A. Murphy of the Financial Committee, for the complete success in handling the meeting of the Institute. The report of the Membership Committee on the following was accepted: R. E. Birchard, Standardville, Utah. Dave Brown, Spring Canyon, Utah. William Burt, Hiawatha, Utah. A. J. Coats, Fort Collins, Colo. R. P. Fitch, Rains, Utah.

Jan 1, 1925

Heap leaching of copper sulphide and oxide ores' has been conducted at Rum Jungle since the end of 1965.A review of operations was made and this led to an examination of some theoretical aspects of copper sulphide heap leaching. Ox,ygen diffusion was indicated to be the factor controlling copper leaching rate at Rum Jungle and in other similar operations. Suggestions are made for measuring the heap leaching rate. Prediction of full scale operational results from pilot scale testwork are discussed.

Jan 1, 1969

ALABAMA. Aldrich.-Aldrich, W. F. Anniston.-Noble, A. E., 20th St. and Wilmer Ave. Auburn.-Brown, R. L., Box 0. Bessemer.-Abbott, C. E., T. C., I. & R.R. Co. Ferguson, V., U. S. C. I. Pipe & Fdy. Co. Williams, E. P., Tenn. C., I. & R. R. Co. Birmingham.-Aldricb, T. H. Aldrich, T. H., Jr., 406 Woodward Bldg. Allen, A. W., 1616 S. 14th Ave. Bowron, J., 1401 S, 20th St. Burbidge, T. A., Browu-Marx Bldg. Coxe, E. H., Tenn. C., I. & R. R. Co. Crawford, G. G., Tenn. C., 1. & R. R. Co. Crockard, F. H., Woodward Bldg. Dimmick, F. D., Dimmick Pipe Co. Ellis, E. E., 1515 Brown-Marx Bldg. Fairbairn, C. T., Woodward Bldg. Fies, M. H., 2316 Highland Ave. Hiller, E., 516 Brown-Marx Bldg. Hillman, M. P. G., 707 Empire Bldg. Ludwig, C. P., 12th Ave. and 12th St. McCormack, G. B., Lookout Mt. Iron Co. McCrery, C., Tenn. C., I. & R. R. Co. Moffett, C. A , 909 Brown-Marx Bldg. Peters, R.. Jr., Brown-Marx Bldg.

Jan 1, 1917

By Met M. E, Worner H. K

During the past two years, a large number of creep tests has been carried out on electrolytic lead, special assay lead and ordinary refined (Port Pirie) lead. Some of these tests have already been reported.1§ In addition, an attempt has been made to estimate the influence of the individual elements present in small traces in Port Pirie lead. The present paper gives the results obtained when small additions are made to "U" lead of the composition shown in Table 1.(which has been used throughout these investigations during the past few years). The additions were silver, antimony, bismuth and zinc. The results of the addition of tellurium have already been communicated. This investigation was intended to run parallel with a similar one using electrolytic lead as a basis and adding one element at a time.Actually, the experiments using "U" lead have got rather ahead of the others. The important point has emerged, however, that the effect of a .given addition may be appreciably influenced by the presence of traces of other elements.In most of these tests, an initial stress of 500lb. per sq. in. has been used. Whilst it is fully appreciated that this stress is higher than those used in practice, it has to be borne in mind that an improvement in creep resistance was *Manuscript received December 11th, 1936.

Jan 1, 1936

The Arizona Committee, consisting of GERALD F. G. SHERMAN, Chairman, ARTHUR NOTMAN, Secretary, NORMAN CARMICHAEL, B. BRITTON GOTTSBERGER, W. L. CLARK, J. C. GREENWAY, W. G. MCBRIDE, FOREST RUTHERFORD, has arranged the following program for the Arizona Meeting, which has been approved by the President of the 'Institute and by the Executive Committee. It is printed herewith for the information of members, and probably will not be changed in any material respect. Monday, September 18, 1916.-Arrive at El Paso, Texas,, 6.30 A.M. Arrive at Deming, N. Mex., 9.30 A.M. Arrive at Chino, Ariz., 11.30 A.M., where luncheon will be served, after which there will be a visit to the Chino mines. From there the train will proceed to Hurley, N. Mex., where a visit will be made to the mill of the Chino Copper Co. Tuesday, September 19, 1916.-Arrive at Douglas, Ariz., at 8.00 A.M. The morning will be spent at the reduction works of the Copper Queen Consolidated Mining Co. "and of the Calumet & Arizona Mining Co. After luncheon a technical session will be held, with "Smelting" as a special subject for discussion. There will be a banquet in the evening, followed by another technical session or-a business meeting.

Jan 6, 1916

By Steve Hubbard, Brad Marchant, Rolando Cuadra

"Triton Mining Corporation acquired the rights to Mina El Limon in Nicaragua in 1993 by international bid. The bid included the gold operations at Limon and an exploration concession of approximately 4000 km2. Triton assumed control of operations and exploration in May 1994.The Limon mine is located in west-central Nicaragua, approximately 100 kilometers northwest of Managua. The climate is tropical, characterized by a wet season from May through October, and a dry season November through April. Gold at Limon is associated with both banded quartz and silicified breccia veins in Tertiary volcanic rocks, belonging to the lower Coyol Group. Mining is from two open pits and one mechanized underground operation. A second underground mine is currently under development for production during 1997.This paper describes the expansion of the milling facility at El Limon from a nominal capacity of 400 tonnes/day, producing approximately 20,000 ounces of gold annually, to the existing 900 tonne per day mill operation. Engineering of the new mill facility was initiated in September 1994 and construction was completed a year later."

Jan 1, 1997

By D. R. Parker

"This paper canvasses emerging trends in public policy and law, which may influence the zinc industry's interest in recycling. There are forces at work beyond direct economic benefits that will drive recycling of zinc, including:• corporate determination to pursue sustainable practices and product stewardship.• public perceptions and pressure,• customer and investor demand,• workforce recruitment, and• protection and expansion of marketsIn this paper, these ""indirect"" forces are examined with particular focus on the zinc industry: It is concluded that, in today's world with an emerging precautionary approach to policy and law making, public perception concerning the environmental implications of metal products, and the need to conserve resources for future generation, a strong industry response is required."

Jan 1, 2000

By C. Richard Tinsley

INTRODUCTION The economic analysis (Chapter 3), the engineering studies (Chapter 10), the credit structure (and the consequential funding sources) - Chapter 11, and the overall feasibility structure for any venture are all directed to determining one major decision element: How much and how certain is the reward for taking these risks? Risk assessment is a surprisingly weak area of analysis and is usually addressed in a checklist fashion. It is much preferable to deal within a risk system so that the inevitable tradeoffs among risks are correctly made. DEFINITION The first step toward risk definition must be to ascertain all of the risks to which a project or a company is exposed; otherwise one will remain ignorant of the possibility of a financially crippling loss until it occurs. (Carter and Crockford, 1974). However, simply stating what "risk" is can lead to debate. For example, risk could be (adapted from Vaughan, 1982): -the chance of a loss - uncertainty of loss -possibility of loss - uncertainty -dispersion of actual from expected results - probability of an outcome different from the one expected - possibility of an occurrence of an undesirable contingency -a condition in which a possibility of a loss exists. For the minerals industry financier, the last definition is probably the most appropriate. However, from a mineral company's point of view the definition might well include the possibility of not achieving the expected financial return. RISK CLASSIFICATION Risk identification will be readily agreed as the all-important first step. There are five major "branches" of risk classification. These are: -Statistical -Modellers -Checklist -Project Financing -Insurance The Statistical set discovered probability theory and any risk discussion soon deteriorates into a mathematical jungle (Megill, 1977; Hartman, 1976; Reutlinger, 1970; and Pouliquen, 1970).Their use of terminology tells its own story: coin toss (binomial distribution), gamblers' ruin, delphi (oracle) techniques, monte-carlo simulations, random walks, etcetera. These techniques inadequately represent the judgements necessary in an increasingly complicated and interrelated world. The risk Modellers have turned to the computer to handle these inter-relationships but soon find barriers because of "simultaneity". Certainly the computer has its uses to conduct various analyses (marketed as "sensitivity" analyses) but very often one finds that this involves changing one or two variables at a time, all other things being equal. Unfortunately, in a modern and complex world all other things do not remain equal. The statisticians will, no doubt, jump to their own defence by citing this

Jan 1, 1985

By W. W. Krech, T. E. Perkins

As fractures are propagated through rocks, energy is absorbed near the extending crack tip. Apparent surface energies for several rocks have been measured by cleavage under dynamic con-ditions. At nominal crack velocities from 0.5 to 500 in (min, measurements showed that fractures propagated in discrete jumps. Calculated surface energies and moduli were relatively insensitive to nominal rate of cleavage. in another set of experiments, rocks were cleaved under high confining stresses. The rocks were submerged in low leak-off fluids which formed a filter cake on the freshly cleaved surfaces (similar to the hydraulic lracturing process). Apparent surface energies were increased substantially as the surrounding fluid pressure was increased. Moduli in bending increased significantly upon application of the first 1,000 psi but were insensitive to stress level at greater pressures. INTRODUCTION For almost 20 years, hydraulic fracturing processes have been utilized effectively to stimulate oil and gas wells. During this period, some process improvements have resulted from studies of fracture orientation, mechanics of fracturing, areas generated, conductivities of cracks, etc. Yet many questions remain concerning the conditions and pressures needed during fracture propagation. In this paper we will report additional studies of the mechanics of fracture extension. It was shown previously3 that large rock samples could be cleaved under controlled conditions so as to measure the apparent surface energy (that amount of energy absorbed per unit area of new surface created). In this paper we consider the effects of two additional factors on surface energies, viz.: (1) effect of cleavage rate and (2) effect of confining stress level. THEORY Cleavage experiments were conducted on rock samples similar to that illustrated in Fig. 1. Blocks of rock several inches wide, 2- to 3-in. thick, and up to 3 ft in length were grooved longitudinally with shallow guide slots. A crack was initiated and allowed to extend along the web as the top of the rock specimen was pulled (or pushed) apart. Auxiliary equipment permits the measurement of (1) force applied at the top, (2) separation at the top and (3) crack length. (Further experimental details will be given in the next section.) The rock beams created by the crack are considered ton be cantilever beams. The deflection (or separation of the rock beams) at any point is calculated 4,5 by the beam Eq. 1.

Jan 1, 1967

By Cínthia Toshimi Ogata

Processos de fundição de ligas de alumínio com altos teores de Mg são um desafio da indústria, uma vez que diferentes taxas de resfriamento ocorrem em geometrias diversas. Este trabalho tem como objetivo caracterizar a liga de alumínio AA5052 com variações em teores de Mg por meio de experimentos de solidificação direcional transitória, e compreender seus efeitos com relação a evolução de parâmetros térmicos, microestruturais, e propriedade mecânica. As leis experimentais de evolução do espaçamento dendrítico primário (?1) com relação a taxa de resfriamento resultam em: ?_1=640 ?T ?_L?^(-1/4) para a liga 5052 com 2,4%Mg e ?_1=300 ?T ?_L?^(-1/4) para a liga com 3,2%Mg. As leis de crescimento de espaçamento dendrítico secundário (?2) com relação a velocidade de solidificação resultaram em: ?_2=27 ?V_L?^(-1,1) para a liga 5052 com 2,4%Mg e ?_2=15 ?V_L?^(-1,1) para as ligas com 2,6%Mg e 3,2%Mg. Maiores teores de Mg na liga AA5052 proporcionaram uma expressiva redução no valor de ?2 para uma determinada VL. A evolução da dureza mostrou-se diretamente relacionada ao tamanho e a distribuição dos intermetálicos presentes, sendo ?2 o fator predominante neste controle.

Oct 30, 2017

One Hundred Sixteenth Meeting of the Institute, Monday, Feb. 18, to Thursday, Feb. 21, inclusive, 1918. Committee on Arrangements J. E. JOHNSON, JR., Chairman BRADLEY STOUGHTON, Vice-Chairman A. R. LEDOUX J. V. N. DORR L. W. FRANCIS F. T. RUBIDGE G. D. VAN ARSDALE MRS. S. J. JENNINGS E. M. SHIPP RALPH W. DEACON ARTHUR L. WALKER The program for the New York Meeting, in February, 1918, as planned by the Committee on Arrangements at meetings in the middle of December, and therefore subject to slight alteration in detail, is as follows: MONDAY, FEBRUARY 18 9 a. m. to 5 p. m. Registration at Institute Headquarters. 10 a. In. Technical Sessions. 12.30 p. in. Luncheon at Engineering Societies' Building. 2 p. m. : Technical Sessions. 8.30 p. m. War Smoker or Patriotic Meeting. TUESDAY, FEBRUARY 19 10 a.m. Annual Business Meeting, followed by Technical Sessions.

Jan 1, 1918

By AIME AIME

The first Diesel-electric locomotives for the Mesabi iron range of the Lake Superior district were put into service last summer by the Oliver Iron Mining Co., U. S. Steel subsidiary. There were ten of these locomotives, rated 1000 hp. and weighing 125 tons each. They are designed for service from 16 to 24 hours per day to haul trains of loaded ore cars from open-pit mines, 200 to 400 ft. deep, on a two to eight-mile haul to the top of the pit. The locomotives push or pull the trains over switchbacks and up heavy grades with 5 per cent maximum against the load. High tractive effort, less smoke, and ability to negotiate sharp curves were among the reasons for the selection of Diesel-electric locomotives.

Jan 1, 1941

By Howard Martens, Pol Duwez

XPERIMENTS were performed on a Cr-Fc alloy Econtaining 44.7 pet Cr in order to determine the heat evolved during the transformation of the a solid solution into the s phase, and the change in volume accompanying the transformation. Since previous measurements on the rate of formation of a from s indicated that the reaction was quite fast as soon as the equilibrium temperature of 820°C was exceeded by some 50°, standard thermal analysis experiments were performed on heating specimens of s at the rate of approximately 40°C per sec. A definite thermal arrest was observed at 870"C, Fig. 1. This result indicates that the reverse seaction of into a is exothermic. From the heating curve of Fig. 1, taking 15°C per sec as the heating rate in the neighborhood of the transformation, 2.4 sec as the time for transformation, and assuming that the specific heat of the alloy at 850°C is an average between iron and chromium, namely 9.5 cal per mol per "C, the latent heat of transformation is approximately 342 cal per mol. The order of magnitude of this latent heat was also obtained by comparing the heating curve of Fig. 1 with a similar curve obtained with pure iron under identical experimental conditions. It was found that the length of the thermal arrest for s was about 1.8 times as long as that for iron. Since the latent heat of the a to 7 iron transformation is 203 cal per mol1, 2 the latent heat of it to a would be 365 cal per mol, which is in relatively good agreement with the value determined from the heating curve. For the determination of volume change, thermal expansion curves were recorded using a specimen containing 44.7 pet Cr and completely transformed to cr by previous treatment. The curves were recorded at a rate of heating of about 4°C per min and at approximately 840°C a sharr, increase in length of about 0.08 pet took place. Fig. 2. It is therefore established that the specific volume of a near the transformation temperature is about 0.24 pet smaller than that of a, and consequently, when the s phase forms in an a matrix, it would tend to shrink away from the matrix. Since the s phase is known to be extremely brittle, these results offer an explanation for the microscopic cracks often observed in the a phase under the microscope. The results of this study are in qualitative agreement with previously published data on stainless steel 19-9DLa and on a Cr-Fe alloy containing 45 pet Cr.' The increase in density due to the transformation from n to s given in ref. 4 is 0.90 pet. These measurements, however, were made at room temperature. whereas the presently reported 0.24 pet is the change at the temperature at which the transformation takes place during heating. In the graph of Fig. 2, the percentage change in length that would be observed at room temperature is given by the length X, which is about 0.27 pet. This would correspond to 0.81 pet in volume change. Acknowledgment This work was done at the Jet Propulsion Laboratory, California Institute of Technology, under Contract No. DA-04-495-ORD-18 with the Army Ordnance Corps, Washington, D. C. The authors wish to thank this agency for permission to publish the results of this investigation. References I H. Klinkhardt: Measurements of True Specific Heats at High Temperatures. Annalen der Physik (1927) 84, pp. 167-200. - H. Esser and W. Runghardt: Influence of the Method, of Dctcrmination on the Measured Heat Content of Iron. Archtvo ffur Dct Eisenhiittenwesen 11934) 8, pp. 37-38. J. J. Gilman, P. K. Koh, and 0. Zmeskal. Delta Ferrite Formation and its influence on the Formation of Sigma in a Wrought Heat Resisting Steel. Trans. ASM 1 1949) 11, pp. 1371-1388. 1 J. M. Thomas: Discussion of ref. 3. Trans. ASM (1949) 41, pp. 3 390-1392.

Jan 1, 1957

By Leonard J. Prosser, Dennis R. Dolinar, John L. Ellenberger, Gabriel S. Esterhuizen, Anthony T. Iannacchione

The room-and-pillar mining method is used extensively in underground limestone mines in the Eastern and Midwestern U.S. The rock mass is typically a near-horizontal, bedded deposit at relatively shallow depth. A survey of 34 mines was conducted in which data on roof spans, rock mass properties and support practices were collected as part of a National Institute for Occupational Safety and Health research project into ground control in limestone mines. The average room width is 13.5 m (44 ft), accommodating large mechanized equipment. The results show that the immediate roof beam can consist of many individual layers and can contain several near-vertical joints. In spite of the room widths, the roof is naturally stable in many mines. Observed roof instabilities can generally be related to excessive horizontal stresses or unfavorable geological structures that cause block fallout or beam failure of the bedded roof rocks. The survey showed that the rock mass quality of the limestone does not vary significantly throughout the Eastern and Midwestern U.S. Roof conditions and the need for support were found to be closely related to the thickness and competence of the first layer of limestone in the roof. The findings highlight the need to identify local geological structures and the roof beam characteristics so that support alternatives can be evaluated. Monitoring and observational technologies that are available for identifying potentially unstable roof are presented, which include: roof characterization using the Rock Fall Risk Index, automated logging of roofbolt hole drilling, microseismic monitoring and displacement monitoring.

By Richard Paul Seelig

The following review covers published information on pressing of metal powders at room temperature. Only those operations are considered which occur between the time the powder is filled into the cavity and the compact is ejected from the die. Thus, this review does not concern hot pressing, coining or sizing feed or flow problems, commercial presses nor designs. It was also necessary to disregard to a large extent the effect of pressing on subsequent operations and on properties after sintering. 'The pressing operation is considered independently in its function to compact loose metal powder into useful shapes which can subsequently be handled. There are some comments by the writer in connection with a few of the findings quoted in the literature in order to stimulate thought and discussion. The selection of references quoted in the text is in some cases arbitrary although an attempt was made to favor papers containing novel ideas, techniques or results which mag stimulate future research. In order to enable the reader to check further into the subjects mentioned, the original, rather extensive, bibliography is appended even though not all the references are touched on in the printed version of this review. The equipment used by various workers, for example a die design created by Bridgman,22 is very interesting. 'The die insert has a conical external surface. The vertical pressure exerted on the punch transmits itself to the die which in turn is pushed harder into its tapered retainer. Thus, the higher the pressure exerted on the punch, the higher also the pressure exerted inwards on the die inserts. Inasmuch as this pressure counteracts the internal pressure from the compact the two stresses balance each other so that it is possible to obtain tremendous pressures without breaking the die. The die collar was made from an oil hardening tool steel, heat treated to a tensile strength of some 300,000 psi. The die was closed at the bottom by a plug made from special tool steels. Bridgman found that there is no steel which will withstand a com-pressive stress of 700,000 psi without continuous slow flow or immediate fracture. Therefore, the only material suitable for use in the pressing punch was sintered carbide. In view of the ingenious design it was possible to use special tool steel as die material. Jones22 raises the question whether this method of pressing has practical application in powder metallurgy. Although these tremendous pressures cannot readily be utilized without many special precautions, the tapered die and retainer idea is believed to be useful even for lower pressures. Bridgman, himself," alls attention to the fact that the properties

Jan 1, 1947

By Richard Paul Seelig

The following review covers published information on pressing of metal powders at room temperature. Only those operations are considered which occur between the time the powder is filled into the cavity and the compact is ejected from the die. Thus, this review does not concern hot pressing, coining or sizing feed or flow problems, commercial presses nor designs. It was also necessary to disregard to a large extent the effect of pressing on subsequent operations and on properties after sintering. 'The pressing operation is considered independently in its function to compact loose metal powder into useful shapes which can subsequently be handled. There are some comments by the writer in connection with a few of the findings quoted in the literature in order to stimulate thought and discussion. The selection of references quoted in the text is in some cases arbitrary although an attempt was made to favor papers containing novel ideas, techniques or results which mag stimulate future research. In order to enable the reader to check further into the subjects mentioned, the original, rather extensive, bibliography is appended even though not all the references are touched on in the printed version of this review. The equipment used by various workers, for example a die design created by Bridgman,22 is very interesting. 'The die insert has a conical external surface. The vertical pressure exerted on the punch transmits itself to the die which in turn is pushed harder into its tapered retainer. Thus, the higher the pressure exerted on the punch, the higher also the pressure exerted inwards on the die inserts. Inasmuch as this pressure counteracts the internal pressure from the compact the two stresses balance each other so that it is possible to obtain tremendous pressures without breaking the die. The die collar was made from an oil hardening tool steel, heat treated to a tensile strength of some 300,000 psi. The die was closed at the bottom by a plug made from special tool steels. Bridgman found that there is no steel which will withstand a com-pressive stress of 700,000 psi without continuous slow flow or immediate fracture. Therefore, the only material suitable for use in the pressing punch was sintered carbide. In view of the ingenious design it was possible to use special tool steel as die material. Jones22 raises the question whether this method of pressing has practical application in powder metallurgy. Although these tremendous pressures cannot readily be utilized without many special precautions, the tapered die and retainer idea is believed to be useful even for lower pressures. Bridgman, himself," alls attention to the fact that the properties

Jan 1, 1947

By W. H. Bassett

W H. BASSETT was elected first vice-president at . the executive session of the new Board on Tues- day afternoon. Karl Eilers, H. Foster Bain, Thomas T. Read, and H. A. Maloney were respectively re-elected as treasurer, secretary, assistant secretary and assistant treasurer. The new Executive Committee will consist of W. H. Bassett, Chairman, and Richard Peters, Jr., H. C. Bellinger, E. De Golyer, Edgar Rickard. The Finance Committee will be J. V. W. Reynders, Chair- man, Henry Krumb and H. G. Moulton. George D. Barron was reappointed Chairman of the Admissions Committee, and F. Julius Fohs put in charge of the Papers and Publications Committee.

Jan 1, 1929

By AIME AIME

It is with the deepest personal sorrow, and with the regrets of the Steel Company of Canada, that I report to you the death of one of our most valued associates, the late Frank B. McKune, superintendent of the Open-Hearth Department of our company. Many of you will remember Mr. McKune for his long attendance at these meetings, for the intelligent interest he took ill them, as well as for his innovations in steel-production practices.

Jan 1, 1940