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By Aarón Morales

El autor de este artículo postula y desarrolla 12 principios, como códigos básicos que deben marcar la ruta de todo comportamiento empresarial. Su cuidado y mantenimiento constituye una de las principales responsabilidades de la alta dirección, requieren ser entendidos por todos en todos los niveles y no están sujetos a negociación, pues constituyen el sustento mismo de la empresa.

Aug 30, 2020

By Nelson Reátegui

El presente trabajo describe los sistemas computarizados utilizados en el centro de operaciones, explotación y beneficio de Hierro Perú, compañía minera localizada en el departamento de Ica. Inicialmente, la función de un sistema computarizado se limitaba a la reducción de costos en la mano de obra y a realizar operaciones básicas en los negocios. Posteriormente, esta situación cambió ya que estos sistemas se utilizan en los niveles de la gestión empresarial.l. Asimismo se explica las aplicaciones de este sistema al comercio, al tipo técnico-científico, así como el cálculo de reservas y el desarrollo del sistema computarizado de performance de equipo.

Nov 20, 1978

By Werner Burger

The last decade has witnessed a rapid development and application of slurry and EPB type tunnel boring machines. Both soft ground types are able to excavate tunnels in unstable ground conditions below the water table with positive face support. The most significant component of the excavation process is the cutterhead and tool con-figuration were the excavation and face support meets the geological challenge. The TBM downstream processes cannot take place unless the cutterhead and tools effectively do their job. This paper will review the current state of the art design for both slurry and EPB cutterheads and highlight both common as well as geological specific design features.

Jan 1, 2007

By Jonathan Bishop, Jacob Croall, Wilder Sánchez

El presente trabajo logra demostrar que los efluentes ácidos mineros se pueden tratar directamente a través de membranas de Osmosis Inversa (OI), logrando cumplir con los más altos estándares de calidad de agua tanto Nacionales como Internacionales. Este es un uso Innovador de la tecnología de membranas para el tratamiento de aguas acidas de minería.

Sep 29, 2023

By Violeta Vigo, Mario Adrianzén

La política de desarrollo de proveedores locales de Newmont Yanacocha tiene sus orígenes en 2002, cuando corporativamente se marca una ruta sobre la importancia de generar valor compartido a través de la maximización de oportunidades de contratación de empresas locales como parte de la cadena de abastecimiento. En el marco de esta política entre 2015 y 2021 se implementaron dos programas para acompañar empresas locales a alcanzar el éxito en su gestión: el Programa de Hand Holding para la construcción del proyecto Quecher Main y el proyecto Articulando Proveedores locales de Yanacocha (APLY), en sus dos ediciones.

Sep 30, 2022

By Brad Murray

Evaluating the performance of a shielded tunnel boring machine (TBM) can be difficult because the ground cannot be observed directly and in relation to the TBM attitude within the excavation. It is difficult to determine whether performance problems are caused by ground loading, steering issues, fine muck packing against the shield, or migration of annular grout around the shield. The Arrowhead Tunnels Project in Southern California uses strain gauges on its shielded hard rock TBMs to detect shield strains early and correlate them with tunneling conditions, thereby increasing the chances that problems will be correctly diagnosed and addressed to optimize TBM performance. The frequent automatic measurement of shield strain has also been valuable by confirming whether remedial methods used to free the machine after stoppages are effective. This paper discusses the qualitative interpretation of characteristic strain patterns on the Arrowhead Tunnels TBM shields and discusses installation details and special considerations for setting up a strain measurement system.

Jan 1, 2008

By Rubén Céspedes

El carbón es un combustible utilizado en la industria del cemento -en tanto fuente de energía calorífica para el uso alternativo o combinado del carbón. Por ello, el presente texto señala el empleo del carbón en la industria minera a través de un estudio de factiblidad que indique la rentabilidad del cambio y sus aspectos como características del carbón a utilizarse, innovaciones a equipos a montar y la influencia del carbón a utilizarse, así como se plantea la conversión del petróleo al carbón

May 1, 1985

By Frederic P. Dewey

THE Bureau of the Mint of the United States Treasury maintains 13 offices for the purchase of gold-bullion, and this paper describes an investigation to establish the reasonable differences in the assay-results at the various institutions which may be commercially allowable in the settlements between them. Beginning with the comparative assay of proof-gold at the Philadelphia mint and the Utrecht mint, which shows 0.00002 as the closest agreement now possible, eight tables of comparative results, taken from the regular work of the service, are given. These tables begin with very fine gold, produced in an electrolytic refinery, showing close agreement. in the assay-results, and follow through decreasing gold fineness and . increasing amounts and complexity of base metals to very impure and complex bars produced at cyanide-mills, some of which give widely-varying results. Next is given a series of results on samples, prepared and sent out to various laboratories in the service, to test the influence of different metals and various combinations upon the' agreement of the assay-results; 11 samples were sent out and each one was assayed from 44 to 71 times, making a total of 623 assays. To these are added 107 assays of identical samples of coin-gold. On a previous occasion,' I have endeavored to show the degree of accuracy that may be expected in the ordinary everyday analysis of various materials, and on another occasion2 I

Aug 1, 1909

By A. Meléndez

El presente trabajo señala el proceso del entrenamiento para Ingenieros de minas en la corporación minera Cerro Verde a través del plan de perfeccionamiento profesional elaborado por la misma empresa privada. El objetivo del plan es darle al profesional egresado, la experiencia práctica adecuada que complemente la formación académica. Asimismo se busca la eficiencia de su profesión, desarrollar la competitividad y el estímulo de superación del egresado dentro de la empresa minera.

Nov 20, 1972

Study on Beneficiation Technology of a Refractory Fluorite Ore in North China

Sep 13, 2010

By Keith L. Harris

The economy continued to expand during the second quarter, but at a much slower pace than expected. According to latest estimates released by the Department of Commerce, the real gross national product (GNP) grew at a seasonally adjusted annual rate of 0.6% compared with a revised growth rate of 3.8%2 for the first quarter of 1986 and 2.3% for the second quarter of 1985 (table 1). The strong growth of personal consumption expenditures, Government purchases of goods and services, and residential investment was moderated by the growing trade deficit, declining investment in business inventories, and the continuing lag in nonresidential investment. Much of the decreased capital spending for the nonresidential sector for the first and second quarters resulted from reduced petroleum exploration and drilling in response to low petroleum prices. Capital spending and trade continue to be areas of weakness for the economy. Real new plant and equipment expenditures for 1986 are estimated to be 1.3% below those of 1985 (table 2). Real net exports of goods and services decreased $24.6 billion, as exports declined 5.6% and imports grew 16.5%. About two-thirds of the $19.3 billion increase in imports was in petroleum and petroleum products, which, because of their lower prices, should help the economy in the future. In response to the sluggishness of the economy, the Federal Reserve System reduced its discount rate from 6.5% to 6% in early July. Inflation, as measured by the fixed-weighted GNP price index, declined from a revised 2.5% in the first quarter to 1.9% in the second quarter because of significantly lower energy prices.

Jan 1, 1986

By Hudalgo Ch. Raúl

El presente trabajo señala la importancia de SIMSA como elemento integrador de las funciones de diversas áreas (los trabajadores y los responsables operativos) en el sector minero. En este sentido, la mina San Vicente ha optado por una función más activa en el control de eficiencias de consumos de materiales, costos, presupuesto y apoyo en sistemas. Como consecuencia de esto, la mina ha mejorado la recuperación del yacimiento a un 80% y reducido la dilución a 30% en condiciones geológicas difíciles. Así también se ha mejorado las técnicas de perforación y sostenimiento y se ha generado un clima laboral ameno entre el empresario minero y sus trabajadores.

Nov 24, 1993

By M Scott, J J. McEwan

Silver and silver alloys tarnish readily by the formation of tarnish on the surface when exposed to a wide range of sulphur-containing atmospheres. This tarnish is unsightly and undesirable and can be removed either with a silver polish or a chemical dip. Polishes are, however, not suitable for irregular and embossed surfaces such as on coins, medallions and jewellery items, because of uneven removal of the tarnish layer and excessive wear. Successful tarnish protection can be achieved by either storing the items away from the aggressive atmosphere or by coating/treating the exposed surfaces with a protective layer. Storage is feasible for collections but is not suitable for items that are handled or worn regularly, such as jewellery. A number of commercial coatings and treatments have been developed, but to date there has not been a systematic evaluation of tarnish protection. This paper details the performance of a range of generic coatings in an accelerated tarnish test. The degree of tarnish was evaluated by means of loss in reflectivity and change in colour. Four coatings/treatments improved the tarnish resistance of silver by more than tenfold. These include an organic lacquer, rhodium electroplating and an organic self-assembled monolayer (SAM) conversion coating. Research is continuing to optimise these coatings. Keywords: silver alloys, tarnish resistant coatings, silver polishes.

Jan 1, 2006

The contribution of minerals to the growth and development of the United States is best demonstrated by the uses which have evolved during the past two centures. During pre-Revolutionary days the colonies were essentially agricultural in character, producing cotton, tobacco, rice, indigo, grains and flour, fish, livestock, dairy products, and timber. Shipbuilding was the major manufacturing industry. In 1763, the total value of exports for Virginia, Maryland, New York, Pennsylvania, and Massachusetts was £2,722,000, of which £55,000, or 2 percent, was for "copper ore, and iron in pigs" (3)1 and £49,000 was for 21,000 barrels or hogsheads of "pot-ash." The value of 75 ships built for sale in 1763 by the colonies was £61,500.

Jan 1, 1976

By C. Travis Anderson

"Nickel is an essential metal in stainless steel, armor plate, and nickel steels and also in nonferrous alleys, such as monel metal and cupre-nickel, which are used in marine service. Nickel is one of the metals that must be greatly restricted in civilian use to provide the amounts needed for our War program. Consequently, it is desirable to investigate every possible substitute.The 5-cent coin no z in use contains 2.3 percent nickel. At the end of 1941, about 450 tons of nickel was being consumed annually to produce these coins. If the nickel used for that purpose in 9141 had been diverted to military use, 15,000 tons of armor plate could have been produced. As nickel is vitally needed for military as well as essential civilian products, it would seem desirable to substitute some other alloy for the 25 percent nickel alloy now being used. The Bureau of Mines has been asked to suggest possible substitutes.The substitute should have physical properties similar to the alloy now being used. It should have a metallic appearance and ring and a reasonably white color, so to be distinguishable from the present 1-cent coin. It should also be reasonably resistant to corrosion."

Aug 1, 1942

By Godofredo Torreblanca

El presente trabajo identifica, inventaria y estima los montos de inversión de los “peligros históricos” que conforman los “pasivos de seguridad” en la unidad de producción Morococha, -en tanto, representan las mayores causas ocultas de los incidentes /accidente, de forma que priorizan el nivel de riesgo que representan para tomar las medidas preventivas y crear un sistema de gestión de seguridad. De otro lado, los pasivos se han codificado para facilitar su administración y seguimiento, en aspectos relacionados con posibles fallas en el diseño de las instalaciones, peligros por antigüedad de equipos y herramientas, peligros por infraestructura minera defectuosa, y todo aquello que pueda representar un riesgo para los trabajadores (labores con secciones reducidas, tajeos sin chimeneas de ventilación, equipos defectuosos o inadecuados, instalaciones inadecuadas, instalaciones eléctricas sub estándares, etc.).

Sep 14, 2009

By Rudy E. Barrientos Ontón

El presente texto describe los datos geopolíticos, reforma económica y poltíca nacional de competencia y regulación minera de uno de los principales líderes en la industria minera, Australia. Dicho país es similar al Perú -en tanto alberga recursos naturales como minerales e hidrocarburos, cuyos ingresos, producto de la extracción, son fuente para la realización de actividades conducentes al desarrollo sostenible.

Sep 1, 2014

By Richard J. Hartman

Current design practice is to select steel sheet piling sections using sufficient section modulus and yield strength to resist the calculated bending moment. Thus, section modulus is the only property of the sheet pile cross section used in the selection process. Full scale laboratory testing documented that section modulus alone is insufficient to predict the strength of sheet piling. During testing, sheet pile sections with equivalent section modulus exhibited as much as 75 percent difference in load resisting capacity. Analytical study following the testing established that, in addition to the traditional longitudinal (vertical) stress in sheet piling, transverse (horizontal) stresses are also present. Transverse stresses reduce the ability of the sheet piling to function in the intended manner. It was found that transverse stresses result from the pressure applied by soil and water and that the capacity of the sheet piling diminishes with increased pressure. All sheet piling is subject to this behavior. This paper describes the testing and the results and establishes that a problem exists. A two dimensional procedure is described that assists in evaluating transverse stresses and their effect on sheet pile capacity. A method of creating design aids for use by engineers is illustrated.

Jan 1, 2006

By Raul Prebisch

Como última parte del análisis sobre la realidad latinoamericana, el presente texto señala el estrangulamiento o crisis del desarrollo, las disparidades sobre la demanda y sus efectos sobre el desarrollo económico, el fin de la etapa fácil de la política sustitutiva, la industrialización hacia adentro y las exportaciones, la reciprocidad implícita en los grandes centros, la necesidad de rebajar los aranceles, la expansión del comercio mundial y la debilidad congénita de la periferia y la relación de precios del intercambio.

Jul 1, 1964

By Willy Contreras, Omar Barrios, Ned Vásquez

Entre los diferentes tipos de riesgos asociados con la minería subterránea, uno de los más críticos son las vibraciones generadas por efecto de las voladuras. En este contexto, las vibraciones por voladura son un riesgo inherentemente ligado con los eventos sísmicos. Por tal motivo, es de suma importancia realizar un estricto control de vibraciones para minimizar el daño al macizo rocoso que a su vez nos permitirá: reducir la sobreexcavación, optimizar los recursos para el sostenimiento de labores, mitigar los riesgos subsecuentes por subsidencia o estallido de rocas y sobre todo la continuidad de la operación minera cuando está cerca a comunidades sensibles a su área de influencia.

Sep 29, 2023