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By Dominc C. Torre

INTRODUCTION Rapidly increasing capacities of equipment used to load and handle material at the face require improved haulage equipment and better methods of transporting the mined materials or "muck" to the shaft or slope and out of the mine to the processing plant on the surface. Increasingly, those transportation demands are being satisfied with underground belt conveyors. Such con¬veyors provide the most readily available, most efficient, and most reliable method of carrying materials in a continuous and rapid flow from the face loading equip¬ment to the surface plant. Almost universally, belt con¬veyors are used in coal mines and those nonmetallic and metallic mines operating in relatively flat bedded deposits. Belt conveyors are available in a wide range of capacities, mainly limited by belt width, belt speed, and weight of the material to be transported. They can be used on the level, on grades, on the surface, or under¬ground. They provide a rapid and constant flow of material, transporting the material as quickly as it is mined. Length of belt conveyors is almost unlimited. Where the haulage distance exceeds the practical capacity of a single conveyor unit, two or more conveyors can be used in series. Single conveyors more than 1.6 km (1.0 mile) long are common; multiple-unit conveyors in series operation are transporting materials over distances exceeding 16.1 km (10 miles). Depending upon mate¬rials being transported, job conditions, cost of the terrain being spanned, and alternative haulage methods avail¬able, conveyors can be conceivably economical for even greater distances. Table 1 lists maximum belt speeds recommended for most materials, relating belt speeds to belt widths. Table 2 lists capacities of typical conveyors of various widths and speeds, transporting commonly mined mate¬rials of various weights. ADVANTAGES OF CONVEYOR SYSTEMS For several years after their initial introduction, belt conveyors were available only with rigid side frames or a supporting structure of steel and concrete. That con¬struction limited underground applications, due to the cost and relative inconvenience of extending or retract¬ing the belt conveyor in the confined underground environment. However, during the last 20 years, wire-¬rope side-frame belt conveyors, as shown in Fig. 1, have become widely used in underground applications. Even wider use can be anticipated with their application to the fast movement of materials in surface mining operations. Advantages of the wire-rope side-frame belt con¬veyors were realized first in panel or section belt haulage in coal mines. Soon afterward, use of those conveyors was extended to gathering and main-line haulage. The mobility of the wire-rope side-frame conveyor is the principal reason for its success. The conveyor can be extended, retracted, dismantled, moved, and reassembled easily, even in relatively confined under¬ground spaces. The intermediate structure consists of rope support stands, wire-rope side frames, wire-rope tie-off stands, and the necessary carrying idlers and return idlers. An important and very attractive feature is the ability to suspend the conveyor from the roof in an underground mine, as shown in Fig. 2, leaving more room for improved housekeeping and allowing passage of face-service equipment, haulage vehicles, and other mining equipment. The conveyor's open construction allows quick and easy visual inspection of its com¬ponents for failures or malfunctions; it also facilitates checking and correcting conveyor-belt alignment. Other advantages contributing to the attractiveness and widespread application of wire-rope side-frame conveyors in main-line, slope, and surface installations include: lower capital costs, lower installation costs, lower maintenance costs, reduced impact on idlers and belting, reduced spillage and minimal cleanup, improved conformation to undulating terrain or mine bottoms, and the ability to span most obstacles without heavy structural support. CONVEYOR CLASSIFICATIONS Underground belt conveyors are classified normally according to their function. Generally, conveyors are classified into one of four main categories: 1) Panel or section conveyors normally receive the material to be transported directly from the face-haulage equipment. 2) Gathering conveyors are secondary haulage units that usually receive material from two or more panel conveyors. 3) Main-line conveyors transport all the material mined in the underground operations to the slope or shaft. Normally, they receive the material from two or more gathering conveyors. 4) Slope conveyors generally operate in tandem with the main-line conveyor, providing continuous Table 1. Maximum Belt Speeds Recommended for General Use Run-of-Mine Hard Ores and Belt Width, Coal and Earth, Primary Crushed mm (in.) m/s (fpm) Stone, m/s (fpm) 356(14) 1.52 (300) 1.52 (300) 406(16) 1.52 (300) 1.52 (300) 457(18) 2.03 (400) 1.78 (350) 508(20) 2.03 (400) 1.78 (350) 610(24) 2.54 (500) 2.29 (450) 660(26) 2.54 (500) 2.29 (450) 762(30) 3.05 (600) 2.79 (550) 914(36) 3.30 (650) 3.05 (600) 1067 (42) 3.56 (700) 3.05 (600) 1219 (48) 3.56 (700) 3.30 (650) 1372 (54) 3.56 (700) 3.30 (650) 1524 (60) 3.56 (700) 3.30 (650) 1676 (66) 4.06 (800) 3.81 (750) 1829 (72) 4.06 (800) 3.

Jan 1, 1982

By Paul. E. Pesonen

Since early in 1940 the Bureau of Mines has been concerned with possible means of utilizing manganese-bearing materials from the Missouri Valley manganese deposit. During the period between July 1945 and August 1947, the Bureau of Mines undertook to complete certain phases of the problem by re-evaluating the results of earlier work and supplementing the findings by additional operations and field studies considered necessary to permit drawing of final conclusions. Distinctive discoloration marks the outcrop of the manganese deposit which is exposed on both flanks of the Missouri River Valley and its major tributaries for a peripheral distance of approximately 523 miles in south-central South Dakota. The apparent magnitude of the deposit, judged largely from observation of the outcrop, had led to much speculation as to its actual value in terms of tonnage and grade. Similarly, investigative work aimed at developing a means of winning a usable manganese-rich product from the deposit had reached no conclusion, except that certain methods showed more promise than others for accomplishing the final objective.

Jan 1, 1948

By Tim Gitzel

Thank you for your introduction, and thank you to the CIM for inviting me to make a presentation to you today. This is my first opportunity to report to you on the status of the Canadian uranium industry and I am pleased to tell you that the industry is in good shape, and well positioned for the future. As you will no doubt be aware, Saskatchewan benefits from the world?s largest known highgrade deposits of uranium as well as from a high level of provincial, public and northern community support. It is within this unique combination of geology and community that our industry operates. Uranium markets have been extremely competitive for a number of years for several reasons. First, deregulation in the nuclear electric power industry has tended to encourage fuel buyers to use up their large inventories built up at a time when rapidly increasing demand was anticipated. Second, alternate sources from surplus commercial stocks, military materials and reprocessed fuel have presented a major additional source of uranium supply. Today, these secondary supplies are meeting about half of uranium reactor feed requirements. Canada (that is, Saskatchewan) is the world?s largest ?natural? uranium producer with about a third of the global production. Saskatchewan?s mines produced more than 30 million pounds of yellowcake in 2002. Despite low prices, steady demand for uranium will continue. In fact, an increase in world uranium production in 2002 helped feed a more than 3 per cent increase in reactor fuel demand. Low cost production is important for surviving low market prices, but investments are based on longer-term strategies rather than simply responding to market cycles. Cost is not the only issue. In these times of increasing regulatory and public scrutiny we must continue to earn the trust of our stakeholders by adopting the highest standards and staying on the leading edge of technical, social and environmental developments. Managing these issues is as important as traditional concerns of ore grade and cost of production. The last two decades of the 20th century saw the Province of Saskatchewan rise to prominence as the leader in uranium production from facilities, which were at the time deemed world class. These facilities are now either at - or nearing - the end of their production years. We are now bringing on new facilities that will position Saskatchewan to remain the world leader in uranium production for many years to come.

May 1, 2003

By John B. Phillips

The mine is entered by a central vertical shaft, strongly timbered, and containing two compartments-one for the passenger cage, the other for the large skips bringing the ore to the surface. A man-way, for emergencies, is also provided, parallel to the shaft. The cage is a single-deck steel box, carrying about thirty persons; by means of arrangements above and below, it can also hoist and lower materials needed in the workings. Levels are run at intervals of 100 feet. In special cases, where the ore conditions warrant, sub-levels are operated, such as those at 1,113 feet and 1,123 feet (Fig. 7), which are connected by winzes with the 11 th level. One of these was pushed for 40 feet, and then abandoned because it was unprofitable to take up ore of the grade encountered. The ore between levels is removed by stoping. The drifts follow the course of the veins as much as possible, with numerous cross-cuts. Winzes, raises, connections, etc., are blasted out where needed. The main drifts are at least 8 ft. high by about 9 ft. wide. All former narrow drifts had to be widened some time ago, by ruling of the Ontario Department of Mines, to lessen the danger of accidents with cars in the small passages. Accurate plans of the under-ground workings are kept in the office, and extensive surveying is always being done underground to keep the maps up to date, measure the cubical contents of stopes, and so forth. Timber is extensively used in the construction of supports and chutes, and in the sinking of the shaft. Steel and concrete are too ex pensive to compete with timber, which 1s abundant in such sections as have escaped forest tires.

Jan 1, 1926

By K. Musgrave

"The ISO 9000 Quality Management System Standards have become internationally accepted as the way to manage quality assurance. The author has developed a Maintenance Management System Standard using ISO 9001as a model and is working with a major basemetal mining company to implement this. This paper describes the structure of the standard and the steps required for its implementation.Using a management standard ensures that a system is maintained, reviewed by internal audit, and when instances of failing to follow the procedures (nonconformances) occur, that corrective action is taken. It also ensures that regular reviews are made and that the sys-tem is continuously improved.The Standard is designed so that if an organization decides to register to an ISO 9000standard, the Maintenance Management System will be in a format that is compatible and can be incorporated with little effort into the Quality System.IntroductionIn reviewing maintenance operations at many mining companies, and often seeing those same organizations some years later, two recurring issues have been noticed..The first issue is how dependent effective maintenance is upon individual supervisors and crews. In one situation, a mine that had an excellent maintenance system in the 1980s. Now, with new supervisors and crews, it is starting to develop a system that will bring it back to where it once was. No written procedures remain from the earlier excellent system.The second issue is that most operations feel that maintenance is the sole responsibility of the maintenance supervisors and crews. Nothing could be further from the truth. Maintenance, like safety, is everyone’s responsibility. If the operator does not report problems and perform daily checks, and if the production supervisor runs equipment until it fails, then nothing the maintenance crew does will prevent emergency breakdowns and lost production. More importantly, equipment will be operated in unsafe conditions, putting employees at risk and, with today’s regulations, leaving supervisors open to prosecution.The Maintenance Management System outlined in this paper is designed to establish the present best practices as standard procedures, to provide a continual review so that these practices are improved in the future, and to identify instances where the system fails so that corrective action is taken. The mine referred to above is using this approach to make sure that, this time, the system it implements will survive."

Jan 1, 1997

By A. M. Khan, I. Fatt

A new type of steady-state thermal conductivity apparatus is presented and described. Results of measurements on Berea sandstone, Solehofen limestone, Bandera sandstone and Bakelite are presented. The measurements were made in a two-hour period at temperatures up to 80C and axial stress to 125 bars. Results show that the thermoelectric heat pump and tbermistor-controlled electric heater can be used in a steady-state apparatus for measuring thermal conductivity of mck. Steady-state is reached within two hours. With Urethane foam insulation, not more than 3 per cent of heat is lost by radial flaw. The apparatus can be used as a comparator or for absolute thermal conductivity determinations. INTRODUCTION Calculations of heat flow through the earth, both for scientific purposes and engineering design, require thermal-conductivity data on rock. However, the high variability of rock often makes handbook thermal-conductivity data of little value. For engineering purposes in particular, it is desirable to have measured data on samples of the rock mass under study. Laboratory methods for measuring thermal conductivity of rock use either time-dependent1-3 or steady - state temperatures .4,5 The time -dependent (transient) techniques give thermal diffusivity from which thermal conductivity can be calculated if the specific heat and density of the sample is known. Most transient techniques require lengthy and involved sample preparation. Also, the accuracy tends to be low. Steady-state techniques are more exact and are the most commonly used. The steady-state methods, however, also have their difficulties. A long time is often required to reach steady state, troubles have been encountered in establishing good thermal contact between the heating and cooling elements and the rock sample, and unaccounted-for heat losses are difficult to prevent. In this paper we present a description of a new type of steady-state thermal conductivity apparatus. With it, measurements have been made in two hours at temperatures up to 80C and axial stress to 125 bars. Sample preparation is simple and no thermal conductivity standard is needed.6 APPARATUS Our steady-state apparatus is an improvement . over the conduction pile used by Zierfuss and van der vliet4 and Somerton.5 A linear heat flux is established through a conduction pile consisting of the rock sample and a standard material of known thermal conductivity in series. The thermal conductivity of the sample is calculated from the ratio of the temperature drop across the sample

Jan 1, 1966

By Donald Hulse

"Mining has been a source of controversy for at least 500 years. “Since there has always been the greatest disagreement amongst men concerning metals and mining, some praising, others utterly condemning them…” (Agricola, 1556). In 2016, it is widely recognized that mineral resources and reserves must give due regard to the social license in order to operate.“Most commonly, the social license to operate (SLO) is understood to refer to ‘the ongoing acceptance and approval of a [project] by local community members and other stakeholders that can affect its profitability’ (Moffat, 2014).” “Social License to Operate has gained traction, in part, because it is also a concept which – while remaining poorly, technically defined – is generally easily and widely understood by community stakeholders (Bice, 2014).”A generation ago we learned that mining is based on a stable platform supported by three pillars, geology, mining and metallurgy. The three-legged stool is a very stable structure (Fig. 1).In 2016, it seems that we have added some other legs to the stool (Fig 2). The Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves (JORC Code) addresses “social, and governmental factors…” (JORC 2012), and refers specifically to social license in Section 4 of the Report Template “Estimation and Reporting of Ore Reserves.”The Canadian Institute of Mining, Metallurgy and Petroleum (CIM) Guidelines refer to “environmental, legal and social data…(CIM 2003).”Compared to these, the 2014 SME Guide is positively verbose stating “a discussion of any potential social or community related requirements and plans for the project and the status of any negotiations or agreements with local communities,” (SME 2014) although in all cases the scope of this disclosure is left at the discretion of the competent person.When there are more than three legs on the stool, it is imperative that all legs be constructed exactly to the design. Any one or more legs that are out of alignment will cause the stool to wobble.Engineers are trained to create designs to meet specifications. Loads can be estimated, forces calculated and cost studies completed that will lead to, not only a stable design, but the most efficient design that meets the specifications."

Jan 1, 2015

By Witold J. S. Ostrowski

The shaft structure being part of an underground mine, depends on programned functional duties, and on geological and hydrological conditions. The majority of Canadian metal mine shafts are in hard competent igneous rocks, which are in an elastic state of equilibrium around the excavation. Others penetrate soft sedimentary or very weak water-bearing rock formations in which the equilibrium varies from plastic to hydrostatic. Knowledge of how to interpret the underground conditions, determine acting forces and design proper structures is essential for the production and safety of the future mine.

Jan 1, 1973

A composite iron ore-reductant pellet is a mixture of fine iron ore and fines of coal/char/coke, bonded at essentially room temperature with sufficient green strength for subsequent handling. In ironmaking, these pellets offer the advantage of fast reduction, utilisation of fines, non-coking coal and coke breeze. The composite pellet-based alternative ironmaking processes constitute a promising route for ironmaking in future. The present paper is a brief review of kinetics and mechanism of reduction of iron oxides into iron and other associated reactions, when these pellets are heated to high temperature. It would draw significantly from investigations conducted by the author and his co-workers.

Jan 1, 1999

By E. L. Martheleur

The use of electricity in coal mines dates almost from the time when it was realized chat it could be used to produce mechanical power. The first motor put in service underground was installed to drive a small pump nearly 40 years ago, and since then the use of electricity in mines has reached an extent undreamed of at that time. We now find its universal adoption in all the mining countries of the world. Great progress has been made in the development of mining electrical apparatus in the last decade, and excellent and adequate material is now available for the use of electricity underground. Although mining accidents, due to the use of electricity, are not frequent, the miner is justified in demanding chat all electrical apparatus for installation below ground be constructed with a greater degree of safety than that used on the surface. That this view is shared by the authorities of the different mining countries is evidenced by governmental regulations relative to the use, erection, and maintenance of electrical apparatus below ground. Those with which we are specially concerned are the regulations for the installation and use of electricity in the coal mines of Nova Scotia. The potential dangers of electricity in coal mines are: Shock or burns by contact from live parts. Shock or burns by contact with parts which, although normally dead, have become accidentally alive. Fire. Explosion of gas or coal-dust Explosion of apparatus.

Jan 1, 1928

By Nelson P. Hulst

COMMITTEES. DULUTH.-Nelson P. Hulst, Chairman; J. B. Adams, W. C. Agnew, M. H. Alworth, C. W. Andrews, R. Angst, William R. Appleby, C. E. Bailey, G. G. Barnum, E. F. Bradt, Mylie Bunnell, George L. Cheesebrough, Peter Christen¬sen, F. A. Cokefair, T. F. Cole, C. A. Congdon, N. Cowling, George H. Crosby, M. D. Cullum, C. d'Autremont, Jr., H. L. Dresser, C. T. Fairbairn. Walter Fitch, F. L. Gilbert, J. T. Hale, G. G. Hartley, E. B. Hawkins, M. S. Hawkins, J. H. Hearding, Louis Hill, L. J. Hopkins, F. E. House, J. C. Hunter, 0. D. Kinney, J. W. Kreitter, E. J. Longyear, Alexander McDougal, W. A. McGonagle, A. M. Marshall, W. N. Merriam, T. D. Merrill, John Millan, P. Mitchell, Clarence Moore, Hon. Page Morris, C. H. Munger, Henry Nolte, W. J. Olcott, A. L. Ordean, Thomas Owens, F. A. Patrick, H. M. Peyton; D. M. Philbin, Capt. Charles Potter (U. S. A.), L. W. Powell, Harry Roberts, Louis Rouchleau, George A. St. Clair, J. U. Sebenius, Joseph Sellwood, Amos Shepherd, W. B. Silvey, George Spencer, George C. Stone, H. B. Sturtevant, George D. Swift, Kirby Thomas, C. D. Thompson, A. D. Thomson, G. A. Tomlinson, Charles Trezona, R. R. Trezona, Maj. J. H. Upham, Charles Van Barneveld, W. W. Walker, J. L. Washburn, A. C. Weirs, H. J. Wessinger, A. B. Wolvin, Dwight E. Woodbridge. HOUGHTON.-W. E. Parnall, Chairman; W. D. Calverley, Secretary; W. B. Anderson, L. S. Austin, Jacob Baer, William Bath, F. J. Bawden., Simon Beahan, John Been, C. H. Benedict, Walter Bloomfield, S. H. Brady, Samuel Brady, Henry Brett, A. L. Burgan, F. I. Cairns, W. H. Cake, Arthur L. Carnahan, William Carpenter, Phillip Carroll, John J. Case, T. L. Chadbourne, W. A. Childs, B. F. Chynoweth, Captain James Chynoweth, H. P. Clausen, F. G. Coggin, H. D. Conant, J. B. Cooper, J. R. Cooper, John Cuddihy, Thomas Cummings, Robert Davidson, J. B. Dee, J. R. Dee, T. S. Dee, Theodore Dengler, M. M. Dennis, Captain Thomas Dennis,. F. W. Denton, A. D. Edwards, R. M. Edwards, C. S. Fales, Daniel Fisher, Henry Fisher, James Fisher, A. L. Floeter, Frank H. Getchell, M. C. Getchell, W. M. Gibson, W. M. Gilliland, James G. Glanville, George Goodale, H. S. Goodell, A. R. Gray, Edward Grierson, Homer Guck, H. D. Haddock, Captain Josiah Hall, John L. Harris, Captain S. B. Har¬ris, Enos Harrold, F. William Hartmann, George L. Heath, C. M. Hoar, Thomas Hoatson, 0. P. Hood, Captain Thomas Hooper, Captain Joshua D. Husking, Dr. L. L. Hubbard, Arno Jaelinig, E. D. Johnson, G. A. Koenig, Edward Koepel, C. H. Krause, R. H. Leach, A. W. Leonard, James MacNaughton, Edward McCormick, Thomas McDonald, R. T. McKeever, F. W. McNair, James McRae, John Mackey, John C. Mann, Major G. A. Marr, Captain Thomas Maslin, Harry Mercer, James Merton, Michael Messner, William F. Miller, Captain J. Milligan, Dr. J. W. Moore, Charles H. Moss, H. F. Nickerson, Charles L. Noetzel, P. H. Paine, John Penrose, Captain John Pentecost, Graham Pope, R. C. Pryor, James Ramsay, J. T. Reeder, Allen F. Rees, J. H. Rice, W. G. Rice, James

Jan 1, 1905

By Clarence R. Zink

A problem has always existed in deep and fast drilling situations such as coal overburden drilling, or when drilling with a tight annulus, such as 9 7/8" bits and 8 5/8" pipe. This problem is the difficulty experienced by blasthole bit and blasthole drill rig manufacturers to attain large jumps in bit and drill rig productivity through bit and rig design, when drilling in these specific situations. In other drilling situations, these large jumps in productivity have been easily attained.

Jan 1, 1998

By George A. Roche

Since our firm was established by Mr. Price in 1937, we have followed an investment philosophy which is based on the belief that investment in growth stocks is the most assured way of achieving superior, long term investment accomplishment. There are many criteria that we use to select growth companies but the most important is a combination of superior management operating in an industry with above average growth potential. This growth stock approach is the cornerstone of our investment strategy for two of the three mutual funds sponsored by the Price organization and for our private clients. However, during the past 5 years we have seen inflation accelerate due to a variety of factors including the inability of our government to meet seemingly unlimited needs with limited revenue sources. While there might be temporary periods of price stability, we believe that inflation will still continue to be the investor's greatest problem in future years. Our conviction that inflation would increase combined with the acceleration of inflation in the late 1960s stimulated an intensive investment research effort, on our part, to identify those companies with strong natural resource bases -- who own or control large, secure, and low cost tangible assets. Over the longer term and in an environment of a depreciating dollar some of these firms should be able to develop and sell these assets at higher prices. While we still believe that investing in growth companies is a sound investment strategy to offset inflation, we also believe that certain natural resource companies will show well above average investment performance. In the newest Price mutual fund, The Rowe Price New Era Fund, we have, as a matter of policy, placed a large portion of the portfolio in natural resource companies.

Jan 1, 1972

By Daniel Connor, O&apos

The Cal-Sag Relief Sewer is a 2.6 m (8 ft 6 in.) diameter 9.1 km (5.7 mile) rock tunnel bored in dolomite for the Metropolitan Sanitary District of Greater Chicago. Included in the project are 18 shafts varying in depth free 70 m (230 ft) to 41 m (135 ft). This paper discusses how Healy/Vanessa reduced costs by eliminating conventional hand excavation by hoisting muck from a high production Robbins TBM (Tunnel Boring Machine) through small diameter drilled shafts and using a trailing rail-utility backup system.

Jan 1, 1985

By Jacque Trottier, Marcel Vallée, Gratien Gélinas

"Mineral exploration in Canada traditionally has gone from boom to bust in cyclical pat-terns following market and discovery cycles, but other endemic factors related to exploration financing and performance have contributed to the amplitude and recurrence of these fluctuations. In view of these problems, junior exploration is reviewed here in a marketing perspective, looking at the 4 Ps: Product, Price, Placement and Promotion.In the 1980s, MEDA incentives gave the shares of junior and mining companies significant price and promotion advantages, and contributed to excessive exploration funding. Many were thus led to minimize the basic values needed for continued investor interest: appropriate levels of product quality, sustained share value and customer satisfaction. Basic changes are needed to improve the marketing of junior mineral exploration in the future, with or without improved fiscal incentives. To be successful, the required improvements must come from the technical participants, but the financial partners also need to be involved.Exploration in Canada must be marketed with vigour, both in Canada and internationally. Exploration, mine development and mine production are essential to our economy. They are environmentally acceptable and they are welcome in Quebec and in most Canadian provinces and territories. Canadian exploration and mining are entrepreneurial industries that must take better advantage of their strengths and achievements and remove the shortcomings that hinder them: nobody can do it for them!"

Jan 1, 1996

By Bill Linville

Producing oil, gas, and coal in sufficient amounts to satisfy U.S. demands for fuels, electrical power, and chemicals promises to be one of the country's major challenges during the 1970's. Adding significantly to this challenge is the urgent task of satisfying soaring fuel and power demands without destroying the natural environment or jeopardizing long-range requirements for resources. The Bureau of Mines, U.S. Department of the Interior, is engaged in a comprehensive program of research to help industry meet this challenge. This report reviews the aims of the research program and accomplishments in 1970; the first 11 sections cover coal programs, nine sect ions are then devoted to petroleum, and the concluding five sections deal with oil shale research. Figure 1 shows the nationwide distribution of Bureau of Mines energy research installations; Full addresses are given in appendix A. Many of the publications resulting from the Bureau?s energy research efforts are discussed throughout the report; others are listed in appendix B.

Jan 1, 1971

By B. Leonard

As of November 2012, the Alberta government listed 53 oil and gas, oil sands, and mining construction projects either proposed or currently under construction. These industrial plant construction projects have an estimated value greater than 105 million dollars. A common construction method employed for industrial plant projects is fast-track construction, which is used to reduce construction time. Contractors begin fast-track construction with highly generic scheduling information. This high level schedule turns into a lower level schedule as more detailed information becomes available. From a contractor?s perspective, a challenge faced using fast-track construction is the visualization of generic and constantly changing project schedules. This paper discusses the use of a Plant Information Modeling (PIM) system, designed to create a 4D animation to visualize project schedules for fast-track industrial plant construction projects. The proposed PIM system creates a modified project schedule by obtaining specific information from a generic construction schedule. Obtaining the information involves grouping schedule activities in accordance with the level of detail in a 3D model, and the level of detail in a project schedule. The modified project schedule is then used in conjunction with a 3D model to simulate the construction sequence in the form of a 4D animation. This allows for 4D visualization of project activities, installation dates, and crane movements. Furthermore, as engineering reaches completion, the PIM system creates a streamlined channel for schedule information updates to be easily uploaded into the model for a more accurate 4D visualization. Through analyzing a nonmodular construction case study, this paper discusses the successes and benefits of the PIM system for 4D visualization, such as increased productivity, shortened construction time, increased constructability, and decreased field costs.

Aug 1, 2013

By H. F. Yancey

Traditionally the Pacific Northwest has relied on hydroelectric power, which has been both abundant and cheap. However, comparatively few hydroelectric sites capable of providing low-cost power remain, therefore the need for supplemental thermal generation, perhaps within the next decade, is generally recognized. Based on the present cost and availability of competing fuels, coal seems to be the logical choice for projected thermal power plants. Power companies and public utilities have become interested in establishing reserves of coal for future use. One deposit explored in 1958-59 lies in southern Thurston and northern Lewis Counties, Wash., near Centralia. Drilling, totaling 22,700 feet, proved the existence of 70 million tons of strippable coal--an ample reserve for the projected power plant. The coal, like most others and particularly those of Washington and Oregon, when mined in full seam section by mechanical methods, would require cleaning to make it suitable for use. The amount and nature of the impurities in this coal dictated a thorough investigation of its cleaning characteristics to establish economic factors and to insure proper preparation-plant design. Therefore, arrangements were made through a cooperative agreement to conduct such work at the Seattle Coal Research Laboratory of the Bureau of Mines. This report describes that investigation. The results are of interest primarily in connection with the utilization of this particular deposit, but some of the information developed is applicable to other deposits of low-rank coals in the West, because the impurities in these coals differ greatly in behavior from those generally associated with the higher rank coals of the Appalachian field.

Jan 1, 1961

By M. H. Leite, R. Corthésy, D. E. Gill

"La connaissance des contraintes naturelles qui prévalent dans les massifs rocheux est un prérequis indispensable pour la conception sécuritaire et économique des excavations comme on en retrouve dans les exploitations minières souterraines. Certains chercheurs se sont attardés à colliger les résultats de mesures de ces contraintes et les ont utilisés pour produire des modèles de prédiction basés sur leur traitement statistique. Ces modèles de prédiction sont très populaires auprès des exploitants miniers puisqu’ils permettent, du moins dans les étapes préliminaires de design, d’obtenir de façon s’apéconomique mais approximative, une partie des paramètres dont ils ont besoin. Dans le cadre d’un projet initié en 1994 avec la collaboration de l’IRSST, il a été décidé de produire un modèle de prédiction englobant une partie de la zone périphérique de la faille de Cadillac, soit une zone plus restreinte que le Bouclier Canadien utilisé jusqu’ici comme région pour l’élaboration de tels modèles. Pour produire ce modèle de nouvelles données obtenues avec une technique permettant d’exercer un excellent contrôle de qualité ont été ajoutées à celles déjà disponibles. Une telle régionalisation des données de base permet d’obtenir un modèle où les intensités et les orientations des contraintes principales sont beaucoup moins dispersées que ce que rapportent les modèles publiés jusqu’à ce jour. Enfin, il est démontré que le modèle proposé pour la région étudiée est en toute probabilité plus sécuritaire que les modèles plus généraux publiés à ce jour. Knowledge of the in situ state of stress existing in a rock mass is essential to the safe and economical design of underground mining excavations. Prediction models have been published, based on the statistical treatment of stress measurement results. Such prediction models are very popular among mine operators because they allow them, at least at a preliminary design stage, to economically obtain part of the information needed, even if this information is approximative. In 1994, a research project financed by IRSST was initiated aiming to produce a prediction model that would comprise a peripheral zone around the Cadillac fault. This region is more confined than the Canadian Shield on which the existing prediction models have been based up to now. In order to produce such a model, existing stress measurement results have been used in conjunction with new stress measurements that have been performed based on a technique which allows full control of the quality of the measurements. Restricting the data upon which the model is based to a more specific region gives a model in which the intensities and the orientations of principal stresses are far less scattered than the results published to date. Finally, it is shown that the proposed model is probably safer for the studied region than the models previously published."

Jan 1, 1998

By John Jermain Porter

(San Francisco Meeting, October, 1911.) THE value of any particular ore, coke, or limestone, for iron-making, depends upon its effect, first, upon the quality or value of the resultant product; and second, upon the cost of smelting. The factors under the first head are the percentages of phosphorus, manganese, and other elements, which remain in the pig-iron ; while those under the second head are the percentages of iron, carbon, or lime, the slag-forming constituents, which must be fluxed, and any other ingredients which give rise to variations in cost of fuel and flux. The first of these criteria of value is perhaps not capable of being reduced to a general formula embracing all cases, since it must vary to a great extent with market-fluctuations. For example, Bessemer pig is worth sometimes more and sometimes less than foundry-pig ; and the premium paid for high manganese varies within wide limits. The second, or smelting-value, however, can be expressed numerically with a fair degree of accuracy; and it is with this phase of valuation that the present paper is concerned. The utility of a means of comparing numerically the relative smelting-values of different ores, cokes, and limestones, is self-evident, although it may not have importance in Northern practice, where materials are largely standardized. On the other hand, there are, especially in the South, many furnace-managers who must use a great variety of materials of widely varying grade; and it is with special reference to this district, and in connection with the efficiency-methods which I have elsewhere proposed,1 that the methods herein described were devised.

Mar 1, 1912