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ANNUAL meeting of the Woman's Auxiliary of the American Institute of Mining and Metal-lurgical Engineers convened on Tuesday morn-ing, Feb. 20, the president, Mrs. H. W. Hardinge, presiding. President Hardinge, in opening the meet-ing, said: "I have the honor and great pleasure to welcome you to our seventh annual meeting. It has been a happy year, though I started in fear and trembling. My fear is partly gone and my trembling becomes less as time goes on. Never has a chairman had such splendid cooperation and harmony in her work; no. matter how much was asked nor what the task, I have always received the same answer, `We are with you, of course we can do it.' Often the road has been untried and the way full of snares, but we have all pulled together. Is it any wonder we have had a prosperous year? I cannot thank the governing -board and officers enough for their help." Mrs. Hardinge described her trip through the West last summer, during which she visited many of the local sections of the Auxiliary. She also spoke of the work of the Rossiter Raymond memorial library which has been started as an activity of the Woman's Auxiliary. Mrs. Reynders read the minutes of the last annual meeting, and Mrs. Kemp read the treasurer's report. The latter showed that on Feb. 1, 1922, there was a bank balance of $683.61 and on Feb. 10, 1923, the bal-ance was $947.93. Mrs. Westervelt expressed the sorrow of the Auxiliary for the death -of Mrs. Florence Howe Hall and of Mrs. Levi P. Holbrook.

Jan 4, 1923

By N. A. Karl, D. R. Wilburn

"This summary of international mineral exploration activities for the year 2015 draws upon information from industry sources, published literature, SNL Metals & Mining (SNL) (Charlottesville, VA) database and specialists in the U.S. Geological Survey (USGS) National Minerals Information Center. The summary provides data on exploration budgets by region and mineral commodity, identifies significant mineral discoveries and areas of mineral exploration, discusses government programs affecting the mineral exploration industry, and presents analyses of exploration activities performed by the mineral industry.Three types of information are reported and analyzed in this annual review of international exploration: budgetary statistics expressed in U.S. dollars provided by SNL; regional and site-specific exploration activities that took place in 2015 as compiled by the USGS; and regional events that affected exploration activities including economic, social and political conditions, which were derived from published sources and discussions with USGS and industry specialists. Commodity and regional compilations are presented in this summary. Because multiple sources were used to develop commodity and regional compilations, statistics may vary depending on the source and type of data that are being reported.The SNL data summarize planned company budgets for worldwide exploration activities in 2015 for 24 nonfuel mineral commodities and metal alloys and are based on company surveys. Surveys focused on precious metals (gold, platinum-group metals and silver), base metals, (cobalt, copper, lead, molybdenum, nickel, tin and zinc), bulk commodities (bauxite, chromite, iron ore, manganese, phosphate and potash), and other commodities (diamond, graphite, heavy-mineral sands, lithium, niobium, rareearth elements (REE), tantalum, tungsten and uranium).USGS data compilations and analyses are based on information provided by USGS mineral commodity and country specialists, as well as industry contacts and published trade journals. The USGS data summarize exploration site data collected for more than 80 minerals and materials, with a focus on base metals, diamond and precious metals. The USGS analyzed available information to assess the level of exploration activity in 2015 and to report trends in mineral exploration activity for the period 2005 through 2015. These analyses identify where mineral exploration is occurring by commodity and region and the intensity of activity that is taking place in each region for selected mineral commodities, and determines those factors that most affect changes in exploration activity."

May 1, 2016

By Gary E. Melickian

Last year's review was characterized as a year of politics and began an era of legislation. The 1972 review can be similarly characterized, with even more rigid health and safety regulations and environmental legislation. The mining industry should be aware of what's happening in the nuclear power and other fields as a result of the National Environmental Policy Act (NEPA) of 1969, where the environmental impact of most major construction activities are already under close scrutiny. Section 102 of NEPA requires that all federal agencies include a detailed statement on specified environmental conditions as part of every report on proposed actions significantly affecting the quality of the human environment. All such environmental reports must consider the same general conditions: • The environmental impact of the proposed action. • Any adverse environmental effects which cannot be avoided should the proposal be implemented. • Alternatives to the proposed action. • The relationship between local short-term uses of man's environment and the maintenance and enhancement of long-term productivity. • Any irreversible and irretrievable commitments of resources which would be involved in the proposed action should it be implemented.

Jan 2, 1973

By W J. Haylock, K Wasiel

PX4 Software Pty Ltd is a Brisbane-based company, which specialises in providing tenement management software to mining and exploration teams operating in Australia and several international jurisdictions, including the United States, Africa, and Canada. Whilst the company is experiencing substantial growth due to a demand from both the minerals and mining technology sector, there is a crucial gap in the market for critical minerals, which will be required to achieve the net-zero emissions goal set by the Paris Agreement for 2050. To help understand and address the technology gap identified by the unprecedented demand, PX4 Software undertook the Annual Survey of Technological Transformation in the Exploration Industry. This survey involved interviews with 12 very distinguished subject matter experts in the fields of Geoscience and Geology from across the globe. From this survey, we have defined eight major categories of exploration technologies. Notably, the most transformative of these technologies over the past 65 years falls into the Geophysical Methodology category, specifically focusing on image and signal processing of both airborne and downhole data. Advances in computing power during this period have significantly improved data processing quality, enhancing orebody modelling, and targeting. This has had a profound impact on the industry. Moreover, the survey reveals that future transformative technologies are expected to centre on the automation of existing processes through AI and Machine Learning techniques. This is expected to help facilitate the identification of critical mineral systems and thus enable the exploration industry to make more informed decisions based on data analysis using Machine Learning and AI.

Sep 1, 2024

By M-A. Thibault, C. Gauthierand, J-P. Gagné, J-Y. Carrier, P. Rochette, G. Dufour

"Anodes consumed in the electrolytic process for the production of primary aluminium are considered consumables. They need to be replaced at regular intervals of approximately one month. The so-called anode butts which are removed from the cells contain the metal supports (rods), cast iron thimbles, crust and residual carbon material. Cleaning is required to remove the waste material before the rods are fitted with new anodes. An inspection is required to ascertain if repairs to the rods are necessary. Presently, this inspection is carried out visually. ST AS, in 2004 in collaboration with Alcoa Deschambault, initiated a project to develop an automated inspection system. The objectives were to find a technical solution to perform these functions with a very simple system. Such a system was designed around ""artificial vision"". The inspection system developed uses only one fixed camera and does not require a separate step in the process for the anode rod assembly to perform the inspection. This paper presents the initial steps of the work performed to develop the equipment and software as well as a summary of the results obtained."

Jan 1, 2006

By Robert Maddin

THE application of electrolytic polishing of metals introduced a new technique for preparing surfaces, especially for single crystals. This procedure has generally been assumed to eliminate the strain introduced by mechanical polishing and to result in a more truly representative surface, particularly in the case of soft metallic materials. However, apparently little information is available concerning specific characteristics of a surface prepared electrolytically. The conventional method of mechanical polishing is known to produce a layer of distorted metal which is usually removed by a suitable chemical etchant. To what depth the strain introduced by mechanical polishing penetrates into the lattice is still obscure. The present investigation illustrates the apparently anomalous appearances of glide ellipses on electrolytically polished surfaces of aluminum single crystals. EXPERIMENTAL PROCEDURE AND RESULTS Aluminum single crystals, 99.975 pct pure, remaining from the investigation of Found,1 were polished electrolytically using a solution of fluoboric acid and a low current density. Laue back-reflection technique, interpreted after the manner of Greninger,2 was used to determine the orientation and the specimen axis rotation of the crystals. Three flat surfaces about 4 mm wide parallel to the specimen axis, one perpendicular to the theoretical slip direction and the other two 1200 apart, were polished mechanically and repolished electrolytically. A tensile load was applied using a Southwark-Emery tensile machine at a rate of about 40 lb per min. Elongation was measured by noting the initial and final gauge lengths. X ray diffraction was used to obtain the usual X and X values in order to calculate the elongation and shear by plotting stereographically the specimen axis rotation by means of the Schmid-Boas formula.3 In Table I may be found the value of the gauge diameter, measured elongation, calculated elongation and shear for the crystals investigated. Fig 1 shows the initial and final positions of the specimen axes of the crystals. [ ] At a low magnification the slip lines developed on specimen Al-I appeared straight and rather evenly spaced. However, at a high magnification, the slip lines were seen to be composed of small markings which were present throughout the length of the specimen (Fig 2). The distance between the markings was fairly constant and their directions all parallel to one another. Fig 3-5, photographed on different surfaces of the specimen, illustrate the interesting appearance of these lines. It may be noticed from Fig 4 that the markings, which present the appearance of

Jan 1, 1948

By AIME AIME

FIVE days, extending from Monday, Feb. 18 to Friday, Feb. 22, inclusive, will be required for the annual meeting this year. The first fours days will be devoted to reading and discussion of papers, general and committee business meetings, two lectures, luncheons, dinners and all the pleasures of a big, general reunion. The fifth day will be given over to an all-day excursion for both men and women by special train to West Point, in celebration of the birthday of the first President of the United States. Washington having been an engineer and now after one hundred and thirty-one years the country having selected as President another engineer in the person of Herbert Hoover, our own past president and honorary member, it is proposed to celebrate with a good old-fashioned picnic and inspect the school. The authorities at the Military Academy have undertaken to welcome the engineers and do whatever they may to make our pilgrimage notable. Other social features planned for the week are numerous. Luncheon will be served as usual at the building each day of the meeting to all members and guests. This year a very nominal charge will be made, primarily to overcome deficits due to irregular attendance. Monday noon, the Non-metallic Minerals Committee will lunch at the Engineers' Club and in the evening the Milling Methods Committee will dine there. The Annual Smoker will be held at Hotel Astor after dinner. Professional entertainment of high order is promised, but not too much to interfere with the numerous group reunions that characterize this func- tion.

Jan 1, 1929

A glance at the following chart reveals that because of the continued poor economy, the slump in industrial mineral production continued into 1980. Gypsum was down 17% from 1979; cement down 9%, sand and gravel, 17%, and crushed stone, 11%. All these downward trends reflect the high interest rates and high costs that slowed construction starts. Domestic fluorspar was down 21% and imports off 14% due to the steel iudustry slump. However, potash production was up 8% and phosphate, 5%. Increased drilling activity spurred au increase in barite production of 25%. Most other industrial minerals posted losses with only a few insignificant increases. As expected, prices were higher, reflecting increases due to high costs for labor, supplies, and above all, energy. Increasing energy and transportation costs also had their effect on industrial mineral production. Railroad freight rates increased 16-22% including fuel surcharge; truck rates increased 11-14%a; and ocean freight rates increased 20% for finished goods. The 1979 shortage of boa and hopper cars did not continue into 1980-most likely due to low production of many of the hulk industrial mineral commodities. All in all, 1980 was not a good Year for industrial minerals.

Jan 5, 1981

When I reached Warren after the "de luxe" South American expedition I had little idea what was in store for me. From the large check Thayer had handed me just before I left New York I was pretty sure the future would be good, and that before long it would involve Anaconda. Evidently, Mr. Thayer had left it to Dr. Ricketts and John Greenway to work out the details The next morning Greenway asked me to come to his office and told me that he and Dr. Ricketts had discussed the question and that Anaconda would make me an offer I could not refuse. They proposed to pay me almost $1000 a month, more than twice my current salary. They had agreed that I should stay with Calumet and Arizona for the rest of the year to help with Bisbee development and anything I could to assist with the New Cornelia plans and construction Of course I could not turn down such a flattering offer, as I had about reached the limit of advancement with a much smaller company in anything save a high executive job, and it would be a long time before I could be ready to change from exploration and geology to operating. Greenway and I agreed that I would stay with him for the remaining eight months of 1916 without any particular title but helping in any way I thought would be most useful. Bisbee and Ajo Study It turned out to be a busy half year, in addition to many good times with my Bisbee friends. The Uplift Club did not meet as regularly as in earlier years, but Mason Ross, Jim Lewis, Bill Gohring, Roy Mitchell, Hubert d'Autremont, Arthur Notman, and I did have many "bull sessions" and poker games. I saw much more of Greenway than before and made many trips with him to Ajo and later to the new

Jan 1, 1976

By Harry M. Conger

Thirty years ago, the U.S. gold mining industry was hanging on by its fingernails. Save for one great mine, the Homestake, most production was coming from copper smelters such as Kennecott and Magma. Even Homestake itself was under great pressure from rising costs and a fixed price for gold. The outlook was dim, to say the least. Today, as it has for most of the past decade, the American gold mining industry stands among the world leaders in production, and in the development of mining and mineral processing technology. What caused this dramatic change? Obviously, the freeing of the gold price was a major factor, as was the decline in South African production, but these events alone could not have created the U.S. strength we see today. It was technology, investment, and the determination of miners to build an entirely new industry that were the indispensable ingredients. The U.S. Bureau of Mines, with great foresight, had begun the research that led to heap leaching before the gold price began to rise, and Newmont had committed to build a small mill at Carlin, a move then considered quite risky. From that point, the U.S. gold mining industry was placed on lower-grade ores then being found in Nevada and elsewhere, but it was soon apparent that we would have to develop new technologies to deal with more refractory ores, carbonaceous as well as sulfide-bearing. This is now being done with considerable success. Despite its success, or perhaps because of it, the gold mining industry has come under pressure from various groups who characterize their activities as motivated by "public interest." The public interest they refer to properly include the health and safety workers and impacted communities, as well as protection of the environment, and with these concerns we miners have relatively little argument. In fact, we consider health, safety and the environment among our highest priorities, and not just because regulations may require us to do so. The argument, however, is not about the regulation of a viable mining industry, it is about a well-organized movement to attack and condemn mining in the media and to misrepresent its importance to the Nation and its willingness to accept responsible regulation. Once largely local or regional, the interest groups to which I refer are now quite large, national in scope, and even becoming international. This trend, taken together with finances raised from their dues and contributions, would make the interest groups formidable adversaries for mining, but their grip on the media enormously magnifies their influence. Unfortunately, it also makes possible the wide dissemination of incomplete, incorrect or slanted information. I am not here to "bash" the interest groups. On the whole, I believe that many of them have made positive contributions to society. As conservationists, however, I question their authority to make, or foster, decisions about which American industries and communities live and which die. To illustrate, I would like to present for your consideration the problem of cyanide, one of the issues over which the gold mining industry is most threatened. CYANIDE-POISON OR MIRACLE SOLVENT? Let me get this out of the way right up front: cyanide in most of its chemical forms is toxic. In some forms it is also listed as a carcinogen. These are adverse characteristics cyanide shares with a considerable number of industrial chemicals, including some that are widely used without the stringent regulations already in place for the mining uses of cyanide. In these uses, by the way, the risk to humans comes from direct ingestion of cyanide or cyanide-bearing solutions, or from the accidental acidification of solutions leading to release of hydrocyanic acid gas. That these risks are under control in mining can be seen from the fact that, in modern U.S. practice, there has never been a documented fatality attributed to cyanide! Because of its toxicity, cyanide cannot enter and be accumulated in the food chain. It can, however, be a threat to birds and animals that ingest cyanide-bearing solutions. Protection against this is, quite properly, a responsibility of individual mining operations, and considerable sums are spent each year to prevent or reduce bird and animal exposures. It should be evident, though, that many human activities, including highway traffic, windmills, use of pesticides and the like, result in bird and animal losses. Mining's use of cyanide, and the measures taken to protect birds and animals, should be considered in context. Cyanide must be kept out of surface streams and groundwater, and existing regulations mandate this. Any cyanide residues left in leach heaps, waste dumps and disused facilities must be eliminated, and we have proven technologies to do this now, just as we have means to detoxify tailings prior to disposal. The gold mining industry decries those rare instances when irresponsible operators fail to deal with contamination, and agrees that they should be held responsible. We do not agree, however, that the great majority of responsible companies should be punished, in advance, for accidents that have never happened. So much for the poison, what about the "miracle solvent?" Is that an overstatement? Well, consider the fact that gold has been called "noble" from earliest times, because it does not oxidize under atmospheric exposure, and that it appeared to the ancients to be utterly insoluble. Later generations of scientists did discover that it could be dissolved, but only by a combination of acids so potent that it became known as aqua Regia. Later still, it was found that chlorine would also dissolve gold, and attempts were made to base commercial processes on this, without a great deal of success. It remained

Jan 1, 1995

By Fredrick D. Palmer

The World is Turning to Coal Peabody?s View ?We believe the world is increasingly energy-short, led by unprecedented demand from population centers and economic hubs in Asia, the Middle East and South America ?This occurs as:?Traditional energy sources are clearly constrained, requiring coal-based alternatives?Energy-rich nations leverage political gain from their assets, and nations urgently look to improve energy security ?In this environment:?Oil, coal and gas face a greater long-term convergence, ?Coal?s traditional regionalized nature becomes global, and ?Coal?s compact energy form becomes an attractive source for liquids and substitute natural gas ?The world is blessed with an abundance of coal to help meet all human energy needs

Jan 1, 2008

By Carlos León, David Estrella, Javier Linares

"Recently, Antamina has completed an expansion program of its operations which increased the thoughput in grinding from acapacity of 109 to 130 ktpd. After commissioning, throughput could be exceeded in grinding and downstream processes but primary crushing became a major bottleneck to the overall production process.With an objective to increase the processing capacity of the primary crusher system, a multidisciplinary team was formed with members of Mine, Concentrator and Maintenance departments, who analyzed the overall context of this process restriction. The main implementations developed were: automatic discharge systems of trucks, logic to count trucks and elaboration of a daily performance report. Following implementation of developed improvements, the numbers of discharged trucks to crusher were increased from 449 to 614 units per day. As a result, the expansion target of 130 ktpd was exceeded and processing capacity was increased from 109 ktpd to 145 ktpd. This improvement adds very significant economical value for Antamina.INTRODUCTIONAntamina is a copper-zinc mine located in the Peruvian Andes. Compañía Minera Antamina is owned by BHP Billiton (33.75%), Xstrata (33.75%), Teck Cominco (22.5%), and Mitsubishi (10%). The mine was commissioned in 2001 with a capital investment of US$2.3 billion, and had a nominal 77,000 ktpd mill capacity. Mining, milling, flotation, and tailings impoundment take place at the mine site, which sits at an altitude of 4,300 m above sea level. The deposit is a polymetallic skarn ore body with intrusive phases of quartz-monzonite porphyry into Cretaceous aged limestone. Copper is present mainly as chalcopyrite with a minor bornite component. Zinc is present as sphalerite. Molybdenum is present as molybdenite. Some lead, bismuth, and silver are associated with the sulphides. The deposit is currently classified into six main ore types [Dechert, 2006], grouped into two categories: copper and copper-zinc. The mill produces four concentrate types: copper, molybdenum, zinc, and lead-bismuth. Copper and zinc, concentrates are transported by pipeline down to the port of Huarmey. Molybdenum and lead-bismuth concentrates are bagged and trucked to port."

Jan 1, 2013

By Dave Gilbert

The Antamina tailings beach is considered a fundamental design component, as well as a predictive control for phreatic surface control. In this sense, the paper point out the development and purpose of the tailings beach , as well as what future opportunities may exist. These present and future opportunities, include implications of the beach as an evaporative surface control thus reducing pond volume. These desireable outcomes include better control of the phreatic surface in a rockfill dam, and reduction of pond water volume.

Sep 21, 2013

By G. S. Scott

Mine fires have occurred since the mining of coal was begun, and they are still occurring. The resulting economic waste may become considerable (219),3 especially if a fire is allowed to assume major proportions or to get beyond control temporarily. It is important, therefore, to act promptly whenever a fire is suspected and to have every action count. To do this effectively, it is necessary to know at the earliest possible moment and thereafter what is happening in a remote or inaccessible area. It is equally important to know before¬hand what may be expected as a result of any proposed combative measure. The logical method of combatting a fire demands the cooperation of both mining engineer and chemist. They should decide the course of action to be taken, drawing upon the mining engineer's intimate knowledge of the physical structure of the fire area, the cost and time required for proposed operations, and the probable efficiency with which they could be carried out, and upon the chemist's knowledge of the results to be expected therefrom.

Jan 1, 1944

By J. B. Warriner

S. A. TAYLOR, Pittsburgh, Pa.-What was the distance of haul? J. B. WARRINER.-There is practically no limit to the haul. The length is determined entirely by the feasible location for a dump. -I have known of hauls up to 2 miles in length. R. V. NORRIS, Wilkes-Barre, Pa.-This paper was originally presented to the Anthracite Section as the result of the appointment of Mr. Warriner as the Chairman of the committee to study this matter and present this paper. As he has stated, he obtained data very freely from all the stripping operations in the region, and it is a type of paper of which we should have more in the Transactions. Two or three things in it strike me as particularly valuable. The two tables, 1 and 2, showing the coal remaining, have been the result of a great amount of study, as it is not an easy matter to obtain data as to the amount of coal left in mining. As an example, one of the, anthracite mines was mined and robbed out in 1850, so the maps show. That mine is today producing 250,000 tons of coal, over 50 per cent. from the bed which on the maps is marked as exhausted. What actually happened is that the seam was on a light pitch inconvenient to mine. There was ample thickness of coal and the chambers were driven at a convenient pitch through this 30,-ft. bed, leaving top and bottom, taking out about 10 ft. The pillars were removed and the working caved and marked as gone. That is the type of area that is now being stripped, which explains the reason for the enormous amount of coal left in, and the fact that Mr. Warriner has worked out the actual results from a large number of strippings is of great interest to the operators in any region handling thick coal which has been mined over in the past, generation. The modern mining, of course, is different. We do not have all the coal we want in big veins, and we do not mine it that way. Another interesting feature of the paper to me was the study of losses. It is not uncommon to assume that after you have stripped off the overburden all the coal goes to market. Mr. Warriner has shown that there is a loss ranging up to 10 or 15 per cent. that does not go, so 'that estimates made on stripping, figuring on all the coal, are subject to this very material correction.

Jan 4, 1917

By James H. Nulty, Joseph S. Roti

INTRODUCTION During a recent panel discussion on the topic of millwater antiscalants, the question was posed: "What would you like to see in the future?" Answer: 'We need an antiscalant that: can be fed without a pump (no maintenance), functions on residual basis (no fault), can be tested for colorimetrically in sub-part-per- mi 11 ion concentrations (no guessing) and will recycle back to the mill from tailings (no cost).” Impossible? Based upon today's level of technology, such a product does not exist. However, a few of the qualifications listed above are certainly food for future thought. Meanwhile, progress is being made in upgrading three essential elements in this critical area of ore processing. They are: 1. Antiscalant reagent research and development. 2. On-line monitoring programs. 3. Reagent storage and feed systems. The objective of this paper is to out- line the current direction being taken in each of these areas and to present case histories as examples of how theory has been applied in field situations to better improve operations. LABORATORY SCREENING TESTS Recent technical papers have explained the various generic chemical raw materials which are available in the marketplace. While the merits of each chemical component are open to debate, the processes used by most major reagent suppliers to evaluate products in the laboratory are fairly standard. Common techniques incorporate both static and dynamic conditions in the search for the most cost effective product. Static Test Perhaps the most common test procedure used is based upon NACE Standard Test Method 03-74, which is "a laboratory screening test to determine the ability of scale inhibitors to prevent precipitation of calcium sulfate and calcium carbonate from solution." The objective of this test is to measure the change in calcium ion concentration in a container of saturated stock solution prepared from calcium chloride and sodium carbonate which is heated in a water bath. After 12 hours at constant temperature (160°), the mother liquor is pipetted into a beaker and a titrated for gm/l of unprecipitated calcium ion. A simultaneous test is performed on stock solution with antiscalant added. The results are then charted to determine the most effective antiscalant (with respect to preventing precipitation of calcite). It should be noted that this procedure examines only the ability of a chemical additive to retain calcite in a saturated solution where thermal stress is applied. This is commonly referred to as sequestration or stabilization. It has been documented that products which act in this manner (i.e., inorganic and organic phosphates) are good scale inhibitors. However, low molecular weight anionic polymers function in a much different manner by distorting calcite crystal size, shape and charge density, thus preventing scale formation. Because of this different mode of operation, static tests may not prove conclusive where polymers and sequestrants are being compared. The simplicity of this test makes it easily adaptable for field use, although modifications are often made.

Jan 1, 1986

By Alessandra Regina Machado Schifino

Neste trabalho foi realizado um estudo comparativo entre as normas utilizadas para validação da solda aluminotérmica em trilhos do tipo Premium – Vignole dos modelos TR, utilizada em reparos de trilhos ferroviários. As normas a serem comparadas são: ABNT (Associação Brasileira de Normas Técnicas), AREMA (American Rail Way Engineering and Maintenance of Way Association) e a Norma Europeia (British Standard – Railway Aplication Track – Auminothermic Welding of Rails). Esta comparação será realizada para avaliar a relevância da variação dos parâmetros utilizados em cada uma das normas e quais fatores devem ser analisados em mais de uma norma para que não haja dúvidas se os trilhos estão aptos para serem colocados em operação. Através da realização dos ensaios mecânicos e metalúrgicos, sugeridos pelas normas, encontra-se defeitos causados por diversos fatores, tais como: processo de fabricação, mau uso dos trilhos, falhas operacionais na soldagem, de preenchimento, de solidificação entre outros. Utilizando-se deste conjunto de informações será possível validar as soldas aluminotérmicas testadas.

Oct 30, 2017

By Foluke Salgado de Assis

O presente trabalho tem como objetivo analisar as propriedades em blocos de cerâmica vermelha. O diferencial e originalidade em relação ao que já existe em termos científicos são as evidencias de que gradientes de umidade são mais significativos em secagem rápida o que provoca a presença de tensões residuais, como também em termos da porosidade em temperaturas de queima diferentes e conformação sob condições de presença e ausência de vácuo na produção dos blocos. Nestes casos, danos estruturais como trincas, deformações e fraturas podem surgir no produto final ou durante o carregamento de serviço devido à diminuição dos valores de resistência mecânica. Os resultados evidenciam que corpos de prova submetidos à secagem rápida em comparação a secagem lenta, bem como a diminuição da temperatura de queima e ausência de vácuo durante o processo produtivo, decrescem a propriedade mecânica citada..

Oct 30, 2017

By Alexsander Orrico Marchesi

Este trabalho foi realizado com o objetivo de identificar os motivos das trocas prematuras dos segmentos da máquina de lingotamento contínuo 1 da ArcelorMittal Tubarão e indicar propostas de engenharia para aumentar a sua confiabilidade e disponibilidade operacional . A metodologia utilizada foi a estratificação dos dados históricos, coletados no sistema informatizado de manutenção da empresa (SIM), para identificar, classificar e analisar as causas das trocas prematuras realizadas. A partir disso, baseado em conceitos de engenharia de manutenção, foram utilizados métodos de análises de falhas, como Diagrama de Pareto, Brainstorming, Diagrama de Ishikawa e Matriz Esforço x Impacto para elaboração de propostas de plano de ação modelo 5W1H visando à eliminação dos problemas.

Aug 7, 2018

By Anna Carolina Cerqueira Neves

As fibras sintéticas vêm sendo gradualmente substituídas por fibras naturais. Em comparação com a fibra sintética, fibra natural demonstrou vantagens econômicas e ambientais. Visto que apresenta características interfaciais com matrizes poliméricas que favorecem a absorção de energia de alto impacto pela estrutura. No entanto, até agora pouco foi avaliado sobre a fibra de cânhamo incorporada em matrizes poliméricas. Este estudo tem o objetivo de avaliar a resistência ao impacto deste tipo de compósito com matriz de poliéster reforçada com diferentes porcentagens de fibras de cânhamo. A resistência ao impacto aumenta proporcionalmente com a quantidade relativa de fibras incorporadas como reforço na matriz polimérica. Este desempenho foi relacionado com a dificuldade de ruptura imposta pelas fibras, resultante da interação da matriz de fibra de cânhamo / poliéster de forma a ajudar a absorção da energia de impacto.

Aug 17, 2017