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By C. F. Dietz

WHEN thinking of industrial relations, we must not confine the term to what is ordinarily called "welfare work;" viz., organizing baseball teams, departmental parties, athletic contests, and such things. These are all of interest but not very helpful in solving the problems of industry. We must think of industrial relations as that understanding developed between workers and management that permits of harmonious progress because of a mutual understanding of each other's problems. Most of the industrial unrest, discontent, mistrust, or antagonism is due to misunderstanding; and that misunderstanding is the direct result of not having taken the workers into our confidence. If they are merely cogs in a machine, employed to do certain things, and have no interest in anything but the receipt of the pay envelope, we cannot expect intelligent harmonious progress. There are still some people who think that the interests of management, or capital invested in a business, and the interests of the worker are diametrically opposed. That is an unfortunate belief; the interests are identical. If the worker does not understand what his part of the work represents, what the management's part represents, and what the invested capital's part represents, he is bound to have a misconception, of the matter and will think only in terms of the pay envelope. The methods used for producing a better understanding between workers and management do not much matter so long as the end is attained. Some plants prefer shop committees; others attempt to work through the foremen in the various departments; others, by personal contact-between the management and the men, especially if a shop is small. It does not really matter how the end is attained as long as the object is accomplished. The best type of industrial relations can probably be attained when the mystery is taken out of industry-when the workers understand what they. are a part of, what their function is, what they are contributing. They should also understand something of fundamental economics-that it is not just a question of getting all they can and giving just as little as possible but that their contribution makes for expansion, progress, and permanence, and opens a field of activity for themselves that other-wise would probably be blocked.

Jan 6, 1925

By F. Chen, L. J. Gaydos, L. M. Demers, D. C. Kuhn, S. C. Sun

"In this report, we demonstrate that NF-KB, a ubiquitous transcription factor, plays an essential role in silica-induced inflammatory mediator production in the mouse macrophage cell line RAW 264.7. Compared to the effect of lipopolysaccharide (LPS), silica mediated a stronger activation of NF-KB p50/p50 homodimer at early phase of poststimulation. Furthermore, activation of NF-xB by silica and LPS appears to be mediated by different signal transduction pathways. Both silica and LPS increased mRNA expression in these cells for cyclooxygenase II, inducible nitric oxide synthase, tumor necrosis factor-a and interleukin- I a. This expression was attenuated along with the inhibition of NF-KB activation. It is well documented that exposure of alveolar macrophages to silica can initiate excessive production of inflammatory mediators and cytokines from several early response genes (1-3). At the DNA level, a common structural characteristic of these genes is the presence of one to five NF-lCB binding sequences (KB) in the 5'-flanking region (4-6). In resting cells, NF-KB is retained in the cytoplasm in an inactive form by binding to inhibitory protein known as hcBcx, hcB~. p 105 (precursor of p50) and p 100 (precursor of p52) (7-9). Upon cellular stimulation, these inhibitory proteins are proteolytically degraded or processed by certain proteases, which allows the liberated NF-KB to translocate into the nucleus as an activated form to initiate or regulate early response gene transcription by binding to its consensus element (GGGRNNYYCC)(7).In this report, we demonstrate that silica can efficiently induce NF-lCB activation in RAW 264.7 cells, and that silica displays different characteristic from LPS in the activation of NF-KB, both with respect to NF-KB subtype composition and the signal transduction pathway that leads to the activation of NF-KB. In addition, abrogation of NF-KB activation by inhibiting the protease can dramatically reduce the mRNA expression of cyclooxygenase II, inducible nitric oxide synthase, tumor necrosis factor-ex (TNF-o.) and interleukin-lex (IL-lex). These findings strongly suggest that NF-KB plays an essential role in silica-induced inflammatory mediator production in the monocyte/ macrophage cells."

Dec 1, 1996

The grades of alluvial ore deposits are low compared with grades of hard rock mining. This factor, combined with other parameters of irregular distribution of particles, bedrock irregularities, size of particles, nugget effect, ore characteristics, and wet horizons, combine to place alluvial deposits among the most difficult to evaluate, and on which to establish an ore reserve with a high degree of confidence. With increased geological input, correct selection and implementation of sampling method, due regard to sample representativity and process design, these confidence levels can be achieved.

Jan 1, 1987

By Oscar Marreros D

Luego de que Centromin realizara los estudios de los taludes del tajo Raúl Rojas a través de los métodos Janbu y Bishop, se recomendó que el talud final del lado oeste se mantuviera con el diseño planeado a 45° puesto que así lo requerían las instalaciones de la concentradora al límite del tajo. Posteriormente, este diseño se eliminó porque se comprobó la estabilidad del talud estudiado. En ese sentido, el presente texto señala los nuevos análisis de mecánica de rocas para la estabilidad en cuña, donde se eliminan los riesgos de seguridad de la concentradora y se disminuye la cantidad de desmonte.

Apr 1, 1991

By M. J. O'Hara

El diseño de taludes económicos y estables es una técnica que se aplica en el minado superficial que va desde la exploración hasta el final de las operaciones de extracción y reforestación. Las especialidades que conforman esta técnica son: geología estructural, mecánica de rocas, mecánica de suelos, sismología y matemáticas. En ese sentido, el presente texto describe el estado actual en que se encuentran estas ciencias aplicadas y sus limitaciones para ofrecer soluciones confiables en el diseño de taludes.

Jan 1, 1972

By John Palomino Melgarejo, Jose Soto

Compañía de minas Buenaventura en concordancia con su política ambiental y en cumplimiento con sus normas legales vigentes ha venido cumpliendo la ejecución del plan de cierre de la Unidad Esperanza; la estabilización Física, geoquímica e Hidrológica fueron la base de los trabajos operativos, para ello se realizó una revisión minuciosa de las especificaciones técnicas de ingeniería de detalle para el cierre de bocaminas con efluentes y se ha propuesto nuevas actividades de ingeniería para la correcta ejecución de los trabajos programados. Así mismo se complementó nuevos productos los cuales dan un valor agregado a los trabajos de impermeabilización de bocaminas asegurando su funcionalidad al largo del tiempo.

Sep 1, 2017

By Mariana Peixoto

Muitos componentes de ferro fundido ficam expostos a altas temperaturas quando em serviço, podendo ocorrer a decomposição da perlita através da difusão do carbono da cementita para as lamelas de grafita, resultando em alteração microestrutural e degradação das propriedades mecânicas. A influência que a temperatura e o tempo de exposição têm sobre a microestrutura de um ferro fundido cinzento foi avaliado em amostras de quatro ferros fundidos de mesma base, com diferentes percentuais de cromo e molibdênio. Ensaios de banho de sal a uma temperatura de 500ºC foram realizados em corpos de prova com diâmetro de 10 mm. Os ensaios foram realizados com tempos de exposição a esta temperatura, após homogeneização térmica do material, de 0, 1, 2 e 4 horas. As análises metalográficas evidenciam a ocorrência da decomposição da perlita. Adicionalmente foram realizados ensaios de microdureza, a qual se mostrou sensível às alterações microestruturais geradas pela temperatura elevada. O ferro fundido com maior percentual de cromo e molibdênio apresentou melhor estabilidade da microestrutura para as condições ensaiadas.

Aug 17, 2017

By Belmira Benedita de Lima

Estudos no sistema Nb-B mostram a fase Nb5B6 com formação peritética a partir do líquido, porém sua estabilidade abaixo de 2.000°C não é comprovada experimentalmente. Há também dúvidas sobre a ocorrência da fase Nb2B3 neste binário. Este trabalho tem como objetivo o estudo da estabilidade das fases Nb5B6 e Nb2B3 nas temperaturas de 1.400°C e 1.800°C. Amostras com composições nas estequiometrias Nb5B6 e Nb2B3 foram produzidas através de fusão a arco assim como confeccionadas a partir de misturas de pós de B e NbB. Pastilhas com composição Nb5B6 foram produzidas com e sem adição de semente da fase Nb5B6. Os tratamentos térmicos em 1.400°C foram realizados por até 10h enquanto aqueles em 1800°C por até 1h, todos em atmosfera estática de argônio. As microestruturas das amostras, tanto no estado bruto de fusão como após tratamento térmico, foram caracterizadas por difração de raios X (XRD). Os resultados confirmam a formação fase Nb5B6 a partir do líquido e nas amostras produzidas via metalurgia do pó. A fase Nb2B3 não é observada nas amostras no estado bruto de fusão e nas amostras produzidas via metalurgia do pó tratadas termicamente a 1.800°C, porém, esta fase se estabiliza nas amostras produzidas via metalurgia do pó tratadas a 1.400°C, indicando sua estabilidade com formação peritetóide a partir das fases Nb3B4 e NbB2, abaixo de 1.800°C.

Aug 8, 2018

By Samuel Vasconcellos

Em plantas de separação do tipo PSA ocorrem oscilações na vazão de ar intrínsecas a este processo, devido à repressurização dos vasos pré-purificadores ser feita em intervalos muito curtos. Por meio da instalação de um buffer tank foi possível tornar a coluna de destilação mais estável, aumentando a produção de líquidos, reduzindo a demanda de energia e otimizando a pré-purificação.

Jul 31, 2018

By Frank Tapia, Aldo Gutiérrez

El presente tiene el objetivo de mostrar las principales actividades que se realizan en la estabilización de taludes a doble banco en Sociedad Minera Cerro Verde SAA (Cerro Verde), con el fin de asegurar condiciones seguras y favorables en las operaciones mineras y trabajos en interacción con los taludes de mina.

Sep 30, 2022

By Rafael Lioji Kogake

O Alto Forno n° 2 é responsável por cerca de 40% da produção de gusa na CSN. Uma das principais utilidades responsável pela transformação do minério de ferro em gusa é o ar soprado que é fornecido por dois turbo sopradores da Central Termoelétrica n°2. Para que ocorra o processo de transformação do minério é necessário que o ar soprado seja aquecido. Isto é feito através dos regeneradores, os quais aquecem o ar para cerca de 1.300°C. Como cada regenerador tem um tempo de campanha, é necessário fazer a troca do mesmo a cada 1 hora. Nesse momento de mudança de regenerador, uma parte do ar soprado é desviado para o regenerador que está entrando em operação e ainda está vazio. Com isso, há uma perda pontual de produção indesejada, além de causar instabilidade no processo. A solução encontrada para reduzir este problema foi aumentar a vazão de sopro durante o período de troca de regeneradores, garantindo assim uma maior produção e melhor estabilidade do Alto Forno 2. Este trabalho apresenta o estudo do problema em questão, a metodologia utilizada para a sua implementação e os resultados alcançados.

Jul 31, 2018

By Célio Souza do Rosário

Os cilindros de laminação sempre foram ferramentas utilizadas para estudos e desenvolvimentos técnicos em laminadores, uma vez que uma instabilidade em seu consumo pode indicar alterações ou problemas no processo. Especificamente nos laminadores de tiras a frio a instabilidade representada pelo aumento no consumo dos cilindros de trabalho indica alterações no processo, na matéria-prima ou até mesmo na qualidade do próprio cilindro. Na Laminação a Frio de Cubatão já foram realizados diversos trabalhos com foco na redução de consumo de cilindros, por se tratar de um insumo de custo elevado e influência direta na qualidade do material produzido. Com o mercado consumidor de aços planos cada vez mais exigente, foi necessário desenvolver novas qualidades de aço com resistências elevadas, espessuras menores e tolerâncias dimensionais mais restritas. Para atingir este nível de exigência tornou-se necessário o investimento em equipamentos modernos, e, sobretudo, promover alterações nos processos de fabricação para a sua adequação. São estas alterações que visam atender tais exigências que podem contribuir para o aumento do consumo de cilindros. Este trabalho tem como objetivo identificar as principais causas relacionadas ao aumento do consumo dos cilindros e buscar soluções para sua estabilização.

Jul 30, 2018

By J. A. Barreda

El objetivo del texto es revalorizar el uso de la madera en la explotación minera, a fin de evitar el desabastecimiento y posterior extinción del recurso vegetal. Si bien la demanda de este recurso cada vez mayor en la industria minera, es necesario evaluar su producción en un futuro inmediato. Por ello, es recomendable que las compañías mineras establezcan bosques de eucalipto como reserva personal para un posterior abastecimiento de la mina. Para el establecimiento de tales plantaciones se requiere del apoyo colectivo, las cuales funcionen a manera de unidades, obteniendo una mayor ventaja en ubicación, vigilancia, control, y mejor explotación. Se requiere 700 Ha de plantacíón de 20 años de edad para su cosecha, asi como para la ejecución del proyecto, un capítal inicial de s/ 33 1688 000 00, que se cubrirá en cuatro etapas periódicas con un intervalo de 5 años.

Jul 20, 1960

By H. Meseck

Dynamic pile test methods to establish the bearing capacity of driven piles were developed in the USA more than 20 years ago. In the Federal Republic of Germany, the first dynamic pile tests were carried out at the end of the 70's. Today dynamic pile tests are successfully used to establish the integrity and bearing capacity of driven and bored piles. The Institute of Foundation Engineering and Soil Mechanics at the Technical University of Braunschweig has developed its own method of measuring and evaluation for the execution of dynamic pile tests. The principles of the dynamic pile tests, the measuring and evaluation plant as well as the experience gained with it in the examination of cast-in-place piles are presented in this contribution.

Jan 1, 2010

By J. W. Stevenson

The need for a separate ventilation department within the management team was recognized by the management of U. S. Pipe and Foundry before the company was purchased by Jim Walter Corporation in January, 1970. Because the coal beds of the deep underground coal properties owned by Jim Walter Resources lay 1300 to 2200 feet below the surface, efficient mine ventilation practices are essential through shaft openings varying from 16 to 22 feet in diameter. The extremely high methane gas quantity indicated to be in the coal bed because of the depth of cover and documented by various U. S. Bureau of Mines tests and demonstrated by early mining proved the need to implement this early management decision. At U. S. Pipe and Foundry mine ventilation was a function of the Mining Engineering Department with ventilation personnel assigned to the mine receiving their day to day work assignments from the mine manager or mine foreman. At Jim Walter Resources, the General Manager - Ventilation reports to the Senior Vice President, Mining Engineering, who reports directly to the President, Mining Division, Figure 1 (Company Organization Chart). Position descriptions are static; however positions are dynamic and consequently the degree of emphasis of specific duties and responsibilities change depending not only upon the aptitude of the individual performing the job but also upon his ability to meet the needs of his supervisors; and ultimately upon his ability to react to the economic forces directing our society. The following describes the duties and responsibilities of the General Manager - Ventilation, Figure 2.

Jan 1, 1980

The paper presents a brief history of endeavours to start a mining education programme which began in the days when Papua New Guinea's first large mine, at Panguna (Bougainville), was coming into production. The status of the Public Investment Programme in Mining Engineering and the facilities being created for the education and training of Papua New Guinean citizens in mining and mineral processing are also described. Future expansion plans are also detailed including those for the commencement of petroleum engineering and geological engineering which would include courses in mining geology, exploration geology, engineering geology and petroleum geology. The paper also looks at the manpower training requirements in the lower levels of mining industry such as pit foreman, blasting foreman and other similar positions. It stresses the need to start mining technical training programs at pre- employment level and at certificate level in a technical college, possibly Lae Technical Colleqe.

Jan 1, 1991

By A. S. Macfarlane

Mineral resource management (MRM) practice has developed in South Africa over the course of the last ten years, with the purpose of integrating previously isolated technical functions into a value chain aligned, process organization, responsible for mine planning and optimization. The implementation of MRM within various companies has met with varying degrees of success, often resulting in incremental improvements in the planning process and, conversely, often becoming the scapegoat for poor delivery on plans and projects. The reason for this has been, amongst others, a lack of a suitable metric to define the success rate of MRM in the business at hand, in terms of its contribution to the bottom line. This paper is the result of extensive research by the author into this subject, which has resulted in the conclusion that economic value added is an appropriate measure that will lead to real optimization and value creation in mining companies, if applied within a new, holistic model

Jan 1, 2006

Mount Isa Mines' Hilton Mine was brought into large-scale production in 1990/91 at a time of sharply falling metal prices. To ensure the operation's survival and eventual prosperity there was an urgent need to reduce operating costs and increase revenue. A target of a 40 per cent increase in productivity over five years was set. Strategies to obtain the required improvements were developed on the basis of greater involvement and increased contribution from the workforce, major changes to the mining methods and the development and application of new technology. This paper describes the organisational, operational and technological changes that have been implemented at Hilton and presents the results achieved to-date.

Jan 1, 1993

By M. du Plessis, J. P. Gouvea

Mesh based areal support is commonly applied in South-African deep-level gold mines. It forms part of an integrated support system that can cater for both rockfall and rockburst incidents. The application has been successfully applied over many years. Operations have different geotechnical conditions and practical considerations, which has led to the development of various types of mesh and integrated mesh-based support systems (i.e. meshing and lacing versus welded or chain-link mesh sheets). Typically rolls or sheets of mesh is pinned with rockbolts to the surface of an exposed excavation. Applications vary from hangingwall coverage in a conventional stope gully to complete excavation coverage in footwall drives of conventional mines or on-reef drives in massive mechanised mines. It is however critical to understand the behaviour of the rockmass and apply suitable support systems.

Apr 26, 2022

By Paul J. O'brien, George N. Neary

"The base metal mine at Buchans, Newfoundland, has been producing since 1928. For many years, mill tailings were disposed of by dumping into a nearby natural watercourse via which they were transported to Red Indian Lake and deposited. In 1965, environmental concerns prompted the establishment of settling ponds near the mine site. Effluents fed to these ponds included slimes washed from mine backfill sand and waste water pumped from underground as well as mill tailings. Dusting around the perimeter of the ponds was first observed around 1970and within a couple ofyears reached serious proportions. A program to alleviate the condition by developing a vegetative cover over the tailings was commenced in 1974. The work was successfully carried out and demonstrated that the large area of waste could sustain a permanent cover of grasses.This paper outlines the experimental work done at Buchans as well as the procedures followed and the problems encountered in carrying out full-scale revegetation."

Jan 1, 1981