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By Pat C. Hautala, J. R. Hoskins

This is a new era for the minerals industry. Never before has there been more need for effective communication. So said Robert Anderson, chairman and chief executive officer of Hanna Mining Co. He was speaking to the American Mining Congress's Communication Workshop. The question is whether there is enough industry concern to meet the challenge. Anderson observed that increased workshop attendance, in continuing tough times, reflects the industry's concern for communication. But, why were students, faculty, engineers, supervisors, and managers not at the conference? Communication applies to every manager, Anderson said. But he was the only operating manager present. And only one company sent operating supervisors. The remaining conference participants were public relations personnel, generally with nonmining backgrounds. And the program dealt mostly with public relations issues. Role of Communication in the Minerals Industry. It is well known that the minerals industry faces economic, political, and social problems. Economic shifts and foreign competition have created an international minerals industry and an international marketplace. This, in turn, calls for worldwide communication. Other factors effecting communication are: • Governmental protectionism as well as regulatory reforms call for increased interaction with governing officials. • Changing social values have created environmental issues and anti-industry attitudes. This intensifies the need for improved public relations. • Traditional work values are shifting towards self-actualization and humanistic movements. The work force is better educated and more informed. Employees demand more satisfaction, equality, and job autonomy. • The mining industry's task of managing its human resources is complicated by layoffs, job uncertainties, and bleak outlooks concerning employee morale and motivation. Technology and Information for a New Era As noted, this is a new communications era, one propelled by technology and information. Technology has led to reduced demand for raw materials by developing substitutes. Copper demand, for example, will never fully recover. Copper cables are replaced by fiberoptics; copper transmission lines, with aluminum. Technology has shifted the US from traditional to high tech and service industries. The speed, frequency, and scope of information transmission have greatly increased. But the most significant characteristic of this information is not the pace of advancing technology. It is the dramatic increase in the importance and frequency of our personal transactions. Knowledge has replaced raw materials and capital as the strategic resource. Information has replaced energy as the transforming resource. And the game against nature has become an interpersonal game (D. Bell, Post-industrial society, Physics Today, '76). In Megatrends, John Naisbitt says that information will soon double every 20 months. So, professionals will become "information workers." And communication will be the life channel of the information age. Thomas Wolfe said you can't go home again. Hanna Anderson said we are, indeed, facing a new day. It will never again be "business as usual." We must move into the information age with the rest of society. We cannot trust that the world will continue to rely on our products. Nor can we place the responsibility and control for problems and solutions outside the minerals industry. Improved communication is not a panacea. But, Anderson said, it is critical to the minerals industry. What is Communication? The word communication is overused. It is applied to every aspect of our lives. Satirist Tom Lehrer got sick of hearing about the need to communicate. He said, "It seems to me that if someone is having all that trouble communicating, the very least he can do is shut up!" Obviously, we cannot follow that advice (though we might wish that some others would do so). Communication is always going on. It is inevitable. Yet we have many misconceptions about com-

Jan 1, 1985

By Alan A. Bergeron, J. L. Michels, R. L. Collins

Advanced communication and monitoring systems were developed and demonstrated in three underground mines representing different mining techniques, geographical areas, and material mined. The first mine was a large coal mine in western Pennsylvania that used room and pillar techniques and continuous mining methods. The system developed for this mine provided private telephone channels, environmental monitoring, and control of underground equipment, all on a single coaxial cable, with all system operations under the direction of a minicomputer. Many advanced features were incorporated into the system, such as paging of roving personnel, two-way section wireless, through-the-earth emergency communication, and redundant signal paths. Television was multiplexed into the system for underground equipment surveillance. A hoist radio system completed the complement of equipment at the mine. The second mine was a magnetite ore mine in eastern Pennsylvania that used block caving mining techniques. A radio system was developed that provided two-way communications between trackless vehicles and roving personnel. A unique system of uhf/vhf repeaters combined with a flleaky-feeder" transmission line offered operational and emergency features not previously found in mine communication systems. Evacuation alarming, personnel paging, fan-hole drill operator communications, and maintenance and safety vehicle dispatch were provided. The system required no dispatcher and operated during power failure. A hoist communications/shaft inspection system completed the installation. The third mine was a deep silver mine in the Cour d’Alene district of Idaho. The system developed for this mine utilizes a single wire pair to provide up to 14 voice channels. A unique combination of PBX, telephone carrier system, and intercoms offered private conversations, selective signaling, and emergency backup communications. Two hoist communication systems were installed to provide a voice link and in-cage belling signal between hoistman and cage.

Jan 11, 1981

By N. Coulson, P. F. Stewart

The Mine Health and Safety Act No. 29 of 1996, as amended, embeds an occupational health and safety management system that facilitates communication between representatives of the state, capital, and labour. In underground mines, two communication loops between these role players serve to separate the production chain of command from the political tripartite relations. Worker-elected health and safety representatives are involved in both communication loops, but are severely constrained in escalating their occupational health and safety concerns to the legalpolitical level. This has a direct bearing on the exercise of the Right to Refuse Dangerous Work (RRDW). As previously reported, health and safety representatives were found to primarily consult their production supervisors in preference to their trade-union representatives. This follow-up article presents production supervisor perspectives on the RRDW. The study demonstrates how, for mineworkers, the two distinct communication subsystems constrain, rather than facilitate, implementation of the RRDW.

Apr 14, 2024

By Alan J. Solomon

The function of advertising is communication. Viewing the advertisements of mineral suppliers exposes the reader to a broad spectrum of purposes: announcements of new products, availability and supply, departmental services, company image, etc. It is the advertiser's hope that the message being conveyed is the same message being perceived by the viewer. To maximize this probability, the advertiser at least must carefully construct precise copy, identify the target audience and select the appropriate advertising medium. A truly successful and efficient ad, however, also must accurately reflect a product's life cycle, i.e., the rise and fall in demand for a product. Buggy whips and radio tubes are classic examples of items formerly in high demand. Industrial minerals are similarly affected by occurrences of product life cycles.

Jan 1, 1983

Any communication system requires at least three elements in order to function: a transmitting device, a receiving device, and a transmission line or propagation medium. Even the device children use, tin cans connected with string, consists or these three elements. One speaks into one can (transmitter), which vibrates at the same frequencies as the voice. The string (transmission path) picks up the vibrations of the can and carries them along its entire length. The other can (receiver) detects the vibration and reproduces the original sounds to a lesser extent depending on distance, tightness of string, type of string, etc. All communication systems depend on these three elements: transmitter, transmission path, and receiver. Communication systems can be divided into three fundamental categories: wired phone systems, radio systems, and carrier current systems. Sections 2.2, 2.3, and 2.4, respectively, describe these systems and explain the basic principles of how each works. Hybrid systems are those systems that use various combinations of the three basic communication methods. Hybrid systems are described in section 2.5. There are some other methods of signaling (stench warning, bell signaling, etc.) that can be used in underground mines to transmit or convey information. These systems, although they cannot be considered true communication systems since they do not provide voice or even two-way communication, are briefly described in section 2.6. 2.2 Wired Phone Systems Wired phone systems are all those that depend on a wire connection between phones with the wire carrying the voice signals. Figure 2-1 is a diagram of two typical wired phone systems.The top panel shows a simple single pair party line system. In this system each phone is connected to a common pair of wires, and a person speaking into one phone will be heard at all the other phones on the line. The bottom panel shows a multipair private line phone system. In this type of system, each phone is connected by its own individual pair of wires to a central switch or telephone exchange. To establish a call between two phones in this system, the lines between the two phones must be connected (switched together) within the telephone exchange. In early exchanges, the connections were made manually by an operator. These exchanges are called Private Branch Exchanges (PBX's). Today, equipment within the exchange can automatically connect each phone to any other phone in the system. These exchanges are called Private Automatic Branch Exchanges (PABX's). There are many different types of automatic exchanges. Some utilize switches to physically make each connection according to the number dialed. Other, more advanced exchanges are completely solid state and may even be computer controlled. [ ]

Jan 1, 1984

By J. R. Mackie

Reserve Mining Company, the first large-scale taconite pellet producer in the United States, mines it's crude ore at the Peter Mitchell Mire located on the eastern end of the Mesabi Iron Range near Babbitt, MN. The ore is processed at Reserve's beneficiation plant on the north shore of lake Superior at Silver Bay, M. The mine and plant are linked by a 47 mile, double track, railroad which is owned and operated by Reserve. (see Fig 1). At rated capacity, the mine can produce 33 million It/yr of crude ore, 15 million It/yr of waste rock and 1.0 - 1.4 million yd3/yr of glacial till stripping. Haulage of all mined material is accomplished using trucks. Ore is transported by tractor-trailer side dump units which have capacitys ranging from 83 to 110 long tons. Waste rock and glacial till is transported in end dump units of 50 to 120 LT capacity. Loading is accomplished by 11/13 yd3 power shovels and 7/10 yd3 front-end loaders.

Jan 1, 1985

By H. M. Otte, A. G. Crocker

SLIP, twinning, stacking faults, and precipitates on well-defined planes in a crystal produce traces that are visible on either a polished or an etched surface. The purpose of this note is to establish the usefulness and limitations of the information obtained from such traces when determining the orientation of single crystals or grains in a polycrystal. Attention will be confined specifically to traces produced by octahedral planes in cubic crystals, though most of the remarks can be taken as more generally valid. The problem of determining the crystal orientation is completely solved in principle' and in particular for the special case under consideration.1'2 Tables are available3 in which the orientations can simply be looked up when given the two or three angles between the traces. Thus a quick and simple method is available for obtaining the orientation of a crystal from surface traces. In this note two examples will be given from recently published papers and will show the use of the method with the aid of the Tables, as well as some of the precautions that should be taken in the procedure. As part of an analysis of X-ray Kossel lines, Peters and Ogilvie 4 determined from them the crystallographic orientation of the specimen. They chose a Cu-5.10 wt pct Si alloy that had been partly transformed from the a (fee) phase to the k (hcp) phase. The latter formed as very straight platelets along the octahedral planes of the a phase, and a photograph (Fig. 7 of Ref. 4) was reproduced in the paper4 of the region for which the orientation had been determined from the Kossel lines. Apart from a very small area (about 0.15 mm diam) near the top center of the photograph, the region shown was clearly all of one orientation. Traces in four different directions were readily identified. Starting with the smallest angle and proceeding counterclockwise, the angles between the traces were measured to be 27° 43', 55° 16', 64 3 43 1, and32"26'. These add up to 1802 08 1, indicating a cumulative error of 8'. The correct values should, of course, be taken from the original glass plates, or at least from prints on distortion-free paper, so the precision of the quoted values is actually greater than their accuracy. The solutions can be looked up in the Tables3 in four ways, depending on how the angles are paired, tion for the minutes of arc is required and the solution obtained will be identical for all the four pairs if the values of the angles are not in error. In a practical situation, such as this one, there are several sources of error, so that the four solutions obtained will all be slightly different. An arithmetic average of the four solutions is mathematically incorrect, but may, in special cases, give an answer close to the correct one. A rigorous procedure for refining the orientation has been described by Mackenzie;5 he gives a least-squares method that can be applied, if necessary, to this type of problem. The orientation thus determined can be compared with the one from the Kosel lines and discrepancies larger than the experimental error assigned to nonor thogonality of the X-ray or electron beam to the specimen. Here the example will only be used to illustrate the general procedure for making a very rapid rough check. From measurements on the stereographic projection, Fig. 9 of the paper,4 we can determine that the surface normal is approximately (0.434, 0.704, 0.562). From the Tables3 we find, using 28°, 55" as a good approximation to the first pair (27°43', 55°16'), that the surface normal is (0.453, 0.678, 0.579).* These two values are within 2 deg of each

Jan 1, 1967

By J. Groyecki, M. Markuszewicz, J. Lassota, A. Zawada

The ratio of stable to unstable inclusions was found to ploy an essential role in the process of sccorldar-y recrystatlizalion in Si-Fe. The analysis of the free energy of inclusions in the range of heat-treatment of individual inclusions to be predicted. The effects MnS. ns inslable inclusions. were investigated. TO secure a high induction, the secondary recryslulliztt-lion associated wilh the texture is necessary. To obtain a low core loss an additional refiuing in the solid state is required. It has been found that sulfur can be more easily removed in racunm than in hydrogen and thai this process was hindered by the prescrzce of INCLUSIONS play an essential role in the development of cube-on-edge texture in Si-Fe. Their function consists in restraining the growth of primary grains up to about 900°C and in passing subsequently into solution at higher temperatures. This process is accompanied by the selective growth of secondary grains with (110)[001] orientation. The general effect of inclusions depends on such factors as the type of impurities, their amount. dispersion and stability, the conditions of diffusion in the space of lattice of metal, and the reactions at the metal/gas interface. In recent years, some of these factors were the subject of a special investigation. A positive influence of Mns, siN,' and vN3 has been established. The quantity of impurities4 and their dispersion5 have been found to be of major importance. Attention was called to the vital importance of diffusion and the conditions under which the impurities are removed from metal., It has also been demonstrated that in Fe-Si alloys by the techniques of powder metallurgy a special opportunity exists to obtain the (110)[001] type texture. 6 The aim of this work was to conduct qualitative investigations on the influence of inclusion stability on the development of cube-on-edge texture in a metal containing approximately 3 pct Si. Experiments were carried out on cast alloys and on those manufactured by powder-metallurgy techniques. The results obtained from these experiments were utilized to explain the phenomena involved and to analyze the relationships between stable and unstable inclusions and the magnetic properties of alloys. EXPERIMENTS AND RESULTS The raw materials used in these experiments were the powder of carbonyl iron with the analysis (in pct) 0.044 C, 0.01 Mn, 0.005 Si, 0.009 P, 0.002 S, traces of Cu, 0.06 Ni, 0.0015 Al, 0.03 Cr, 0.02 Mo, 0.01 Ti, 0.002 Co, traces of Pb, and the powder of silicon containing 94.14 Si, 0.003 S, 0.048 C. The powders were ground and mechanically mixed in 100-g batches. and then pressed at 9 tons per sq cm into 74 by 24 by 8 mm blocks. Sintering was carried out at 1100°C for 12 hr in vacuum (2 x lo-' Tr) or in hydrogen. In this instance the material was heated slowly and subjected to prolonged soaking at 350°, 650°, and 750 2C, respectively, to secure reduction of ferro-oxides. This was checked by making measurements of the dew point, which was found to change from -15" to -35°C after reduction. The compacts after sintering were hot-rolled to 2.4 mm, annealed at 800 C, and finally cold-reduced to 0.35 mm with intermediate annealing at 800°C at a gage of about 0.8 mm. Impurities were added in the powdered form and mixed with iron and silicon powders. Sulfur in the elemental state, electrolytic manganese, and pure aluminum oxide were employed. Besides, to obtain a material with low contents of impurities, especially

Jan 1, 1967

By H. K. Birnbaum, H. B. Aaron

he authors suggest that a number of the types of yield phenomena which have been observed in high-purity fcc metals are due to dislocation interactions bccurring at the surface of the crystals rather than due to volume effects. Since rather different inter-pretationS2,7,12,14,15,21-23 of these effects have been suggested, it is of some importance to ascertain the role of the surface in these yield phenomena. It should be first noted that the high-purity fcc metals appear to exhibit several distinct types of yield phenomena. The "unloading yield point" which is observed on reloading the specimen after removing the applied load has been found to be independent of the time of holding in the unloaded condition. If however the specimen is aged while under load and re-tested without removing the load, a yield point is observed which does depend on the aging time and tem-perature. Feng and Kramer suggest that the removal of the unloading yield point on removing sufficient material from the surface of the specimen indicates that the effect is associated with dislocation interactions at the specimen surface. Their observations are counter to those of Haasen and Kelly5 and Birnbaum.12 Since the unloading yield points are extremely small (-2 pct of the flow stress) the results of the surface removal will depend on whether the material is removed uniformly over the gage length. The introduction of small etch pits or the removal of more material from one portion of the specimen than from another will result in preferential yielding and obliteration of the yield point. With the normal electropolishing techniques it would be difficult to avoid these effects. The data obtained by Aaron and Birnbaum, Fig. 10, on aluminum polycrystalline specimens indicate that, although the unloading yield point and the strain-aging yield point are not simply additive, a time- and temperature-dependent yield point is observed under conditions where no creep is observed. This does not agree with the results of Feng and Kramer but does agree with the results on copper15 and gold.7~23 The source of the discrepancy may be the procedure used by Feng and Kramer to correct their time-dependent yield points for the effect of creep. Since the strain-aging yield point is not independent of the pre-aging strain rate, Fig. 11, the effects of creep cannot

Jan 1, 1967

By J. C. Loretto

"OPENING REMARKS Yesterday and today we have heard some very interesting papers on operating matters and some of you are probably wondering what we are now doing talking about Communications in Plant Design. Let me tell you! Before the techniques we have heard being discussed can be used, there has to be a properly operating plant. It is certainly a fact that many mineral processing plants achieve only limited success and a number of them can even be said to be failures. Some of you sitting here are probably living with operating problems that are clue to errors in the design.If the histories of these problem plants are examined, it will be found that in many cases, the necessary skills were available during the period of the plant design. There was extensive operating know¬ledge together with a full range of project expertise. Why then the failures? In a substantial number of cases it can be traced to the old, old problem of communications. As plants get bigger, money costs more and smooth startups become more important, it becomes less and less economic to fix up any design errors during plant operations.During our careers in mineral processing, nearly all of us will be involved in at least one plant design and I feel that it is as well if we understand some of these communication difficulties that can lead to a problem plant. There is little point in us being experts in mineral processing if the knowledge we have acquired doesn't somehow get incorporated into the plant.I would, therefore, like to present this short paper that mentions a few of the significant communication problems that can occur during the design of mining and mineral processing plants, together with some thoughts on answers to these problems."

Jan 1, 1973

By Charles Will Wright

The present struggle for economic and industrial supremacy by the Communist world is against the United States, its main target, and the other Free World nations. The basis of industrial power is minerals, so the Communist nations are building up mineral production within their borders, often regardless of costs, and are acquiring quantities of mineral products from Free World countries for future use. They are contracting for additional supplies and advancing funds for the development of these quantities. A number of the less developed mineral producing countries of the Free World are being infiltrated by Communists and Communistic influence. This situation is well known, but as yet little has been done to oppose these activities or to awaken the public to their seriousness. The Communist countries are still far behind the Free World Nations in production of many essential minerals. But, shortages are being made up from Free World nations in exchange for petroleum, manganese ore, chromite and other products. Restrictions on shipments of strategic materials to Communist countries have not been maintained.

Jan 1, 1964

By Leonard Harris, Rosa H. Harris

"It is becoming increasingly obvious to mining and exploration companies, when operating overseas, that their activities should not conflict with the interests of the surrounding communities. The world's largest gold heap leach operation, Minera Yanacocha has installed community assistance programs in Peru concerned with health, education, electrification, agricultural assistance and road improvements. The programs are conducted with joint venture partners consisting of the company, the community people, the contractors and suppliers, government and non government organizations and a ladies association composed of the employees' wives and female staff.IntroductionThe l 990's is the decade highlighted by enormous investments in mineral exploration and mining projects in the developing world. Figure 1 illustrates the distribution of exploration spending by mining companies in 1995."

Jan 1, 1997

By C. A. Clark

The Chagres Smelter is located 80 kilometres north of Santiago - Chile, in the middle of an agricultural valley which is also one of the poorest districts in the country. This condition sets the main focus for the smelter's Corporate Social Responsibility (CSR) programmes, which ultimately aim at building self sustainable social and economic capital in accordance with the local capacities. With the help of Anglo American's SEAT (Socio Economic Assessment Toolbox), a corporately developed instrument designed to help the operations understand the needs of the communities and the impacts of those operations, the Chagres Smelter implemented several programmes, such as the CETTA (Experimental and Applied Technology Transfer Centre) programme. This project started in 2003, and consists of creating a centre for the transfer of sustainable techniques and skills for the small agricultural and livestock producers that live in the rural areas near the Chagres Smelter. Its main impacts are: Improved production quality (goat cheese and bee honey) and access to relevant markets, improved training and self-sustainability levels of producers, enhanced socio-economic level of the District's inhabitants by improving their income earning opportunities and technical knowledge, creation and promotion of a local brand as a symbol of quality products from the valley and a positive environmental impact of good breeding and native flora protection practices in the area. Other relevant social programmes are the 'Environmental Strivers', which created a recycling centre in the community; and the 'Beautiful Valley" project, which provides management knowledge and skills to local youngsters and leaders who can contribute to finding solutions for local environmental needs.

Jan 1, 2007

By Ben Bradshaw

Context ? Community engagement has become an increasingly significant and challenging part of mineral exploration and mine development; indeed, opposition from communities proximate to a proposed mine site has been known to derail technologically- and financially-sound projects. ? These cases suggest that mining firms need to better understand how to engage constructively with local communities in the pursuit of their claims. ? While a range of publications exist promoting various community engagement strategies, these recommendations, when viewed as a whole, are disjointed and largely untested in real development contexts. Aims of Presentation 1. Synthesize industry, NGO, government and academic publications focused on community engagement best practice in order to highlight those practices that are most commonly recommended. 2. Review the (Canadian) mining industry?s experience with some of these strategies based on existing case material in order to identify the extent to which commonly prescribed strategies are used and validated in practice.

May 1, 2010

By M Scoble, A Ostry, J Shandro

Mining companies are not ill-informed on the topic of community health. There have been a number of research studies that have illuminated community health issues associated with mining, especially in the western Canadian province of British Columbia. However, what is missing amongst the literature is the perspective of mine managers and mining executives on this topic. This is important as mine managers and executives face a number of issues related to community health and are under pressure to consider the topic in more detail. This paper presents results from an exploratory qualitative investigation based on grounded theory research techniques into current community health considerations from the perspectives of mine executives and mine managers working in Western Canada. Interviews were conducted between February and May 2012 with 11 mining versus ten mining executives and managers who represented operating mines or mining umbrella organisations in Western Canada. Participants report on general community health issues that are perceived to be important, the perceived role that the mining sector should play?in contributing to community health and how this differs in Western Canada as compared to locations abroad, and?risks companyÆs face in making community health contributions. This paper concludes by drawing attention to pressing health needs that are present in Northern, rural and Aboriginal populations in Western Canada and provides a platform for future research initiatives focused on improving the health and well-being of communities associated with the mining industry. CITATION:Shandro, J, Scoble, M and Ostry, A, 2012. Community health considerations from mining executives and managers in western Canada, in Proceedings International Mine Management 2012, pp 97-104 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 20, 2012

By S. E. Cook

This article uses the case of the Royal Bafokeng Nation to argue that royalties and dividends from mineral resources, if managed well, can provide direct benefits to the surrounding community even while the state collects its share of mining revenues through taxation. The key to this model is the effective management of the resource income flowing into community coffers. Where some of this income may fund urgent interventions in the community, a portion of the income can also be used to establish an intergenerational wealth fund to meet the needs of future generations. As a depleting resource, minerals like gold and platinum are not a sustainable source of income, and must be replaced over time by more regenerative income streams. These strategies and dynamics are manifest in the Royal Bafokeng Nation?s status as both community and quasi-municipality, a labour hosting and a labour sending community, a mine operator and a mine owner. The Royal Bafokeng Nation also owns one of South Africa?s largest community-based investment companies, which channels revenue derived from platinum deposits into a broad investment portfolio that in turn funds an aggressive social development program for 150,000 people living in twenty-nine rural villages.

Jan 1, 2013

By L. Wilson, M. Kotzel, T. Pienaar

An empirical equation is presented for the maximum airblast from unconfined charges. This has been tested at a number of sites and with charges ranging from 0.1kg to 311kg. The equation is developed to predict community response to potential explosive test range sites and the testing has added to our knowledge of the effectiveness of mitigating measures. The first site had 10m to 15m high walls that were intended to ameliorate the airblast. These walls functioned to a limited extent and reduced the airblast levels by 2dB to 5dB. The airblast was affected somewhat by topography. Noise levels at the nearest residences exceeded 130dB for charges larger than 1kg, whereas the vibration levels were very small. Formal complaints were received where the airblast level exceeded 128dB as per conventional expectations. Pedestrians and pets in the suburbs were startled by the blasts, emphasizing that the community response is much more sensitive to noise and airblast than vibration levels. The maximum airblast levels were too high for this site to be used on a regular basis. At another site, the airblast levels were significantly increased downwind by up to 10dB due to a moderate wind. A third site, at a quarry, produced unconfined airblast levels beneath the derived limits, but are much higher than the normal quarry blasting. By involving community forums there were no complaints, possibly due to desensitization by the normal blasting activities. The study has highlighted new areas for research in understanding the effect of noise, air blast and vibration on the low cost and informal housing typical in South Africa

Jan 1, 2011

By Sarah Wilson, John Kaplin

Plans are underway to extend commuter rail service underground into downtown San Francisco. The Salesforce Transit Center (STC) was completed in 2018 and will serve as a new transit hub, including a commuter rail station after two future connecting tunnel segments are completed. The northern segment, known as the Caltrain Downtown Extension (DTX), which will extend the rail line from its current terminus at 4th and King Streets to the STC, is currently in Preliminary Engineering. The southern segment, the subject of this paper, is a 1.6-mile tunnel known as the Pennsylvania Avenue Extension (PAX), which is currently in the pre-environmental planning stage, with alternative alignments under evaluation including single bore versus twin bore options. This paper discusses project challenges, including highly variable tunneling conditions in soil and rock, a congested urban project site with limited space for construction staging, alignment crossings of large existing buried infrastructure, and complicated interfaces with future and existing rail operations.

Dec 1, 2022

By J. C. White

"During the early development of the Mattabi Mine in 1970, discussions with the Ontario Government revealed their policy of prohibiting, as much as possible, the development of new, isolated, single-industry townsites. Subsequently, Mattabi located its first housing in the Township of Ignace, which is situated 50 miles from the site of the mine and plant. Over 200 employees now commute 100 miles daily to and from work.This paper describes the experience gained and discusses the advantages and disadvantages of a remote townsite."

Jan 1, 1976

By Ludmila Vieira da Silva Matos

O presente artigo investigou como a condição de operação das zonas de resfriamento em máquina de lingotamento de placas contribui para o desempenho de lanças air mist. Tal investigação foi realizada no laboratório da Spraying Systems Brasil a partir das premissas de projeto de uma nova máquina de lingotamento e um novo conceito de lança air mist: menor consumo de ar comprimido, amplo turndown e qualidade de cobertura por toda a curva de operação do resfriamento. As curvas de performance foram montadas para diferentes condições de utilização de ar comprimido: de 1,5 a 4,5bar de pressão constante. Cada lança teve das vazões mínimas às máximas de água ensaiadas. A qualidade do perfil do jato produzido foi verificada para cada ponto das curvas obtidas, em mesa de distribuição no laboratório da Spraying Systems. Com as imagens em mãos, foi possível selecionar aquelas condições de vazão de água e pressão de ar comprimido com melhores perfis de jato e cobertura. Como resultado, a fabricante da máquina pode validar e/ou modificar a curva de trabalho de resfriamento da máquina e garantir as melhores condições do perfil do jato e uniformidade de resfriamento.

Oct 1, 2019