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The North Saskatchewan River flows southwest to northeast through a 22-km-long valley in the City of Edmonton, supplying the drinking water to dozens of downstream communities. During heavy rains, combined sewers occasionally overflow into the river, which has a significant negative impact on the water quality and the sensitive environment. The West Edmonton Sanitary Sewer (WESS) W12, a syphon connecting the Rat Creek Trunk to the Gold Bar Wastewater Treatment Plant across the river, was designed and constructed to take the overflow to the wastewater treatment plant. Due to the complexity of the project, various 3D technologies were applied to facilitate decision-making processes. 3D models were developed for design review and design conflict detection, while 4D models were established to help create a robust construction schedule. Construction sequencing animation was used to convey design intents and demonstrate construction stages to contractors and workers. The combined applications of 3D technologies helped the project team to identify critical issues, and assured effective communication among engineers, management, contractors, and other parties. Therefore, it provided more opportunities for the success of the project.

Aug 1, 2013

By T. R. Heflin

The paper provides a comprehensive discussion of pump selection for the hydrometallurgical industry. Material suitability, in addition to proper size and design, will provide extended life for pumps in erosion /corrosion service.

Jan 1, 1979

By Roger C. Parsons

"The problems presented by ice formation and interference with processes, structures and mechanical operations in the mining industry can be expected to increase sharply as more of our mineraI needs are supplied from the far north. A process of rapid ice destruction is presented which lends itself to the effective removal or penetration of ice. Suggestions are offered for applying the system to problems related to mining activity in cold environments. The system can be readily adapted to large-scale operation, the reactant components being transported in crystalline form and volatilized on site.IntroductionThe number of operational mines in northern environments, relative to the number of mines in the temperate zone, will increase in the years ahead. This is not surprising, because:(a) in the past, those mines closest to centres of commerce had minimum transport charges and hence were more economic to develop;(b) great centres of commerce were far removed from northern environments;(c) the exhaustion of ores and lowering of grades in temperate zones now offset to some degree the extra transport costs applied to northern ores;(d) the abundance of excess energy in the north in the form of oil, gas and hydropower attracts mining as a means to justify its development; (e) assuming that the frequency of mineral occurrence north of the 52° N latitude is no different than south of it, there are many deposits waiting to be developed.As a result of current and projected activity in northern environments, we are faced today, and will be increasingly so in the future, with mining problems rarely encountered before-problems related to below-freezing temperatures. Engineering activity in permafrost regions will increase as new mining ventures are developed north of the 52° N latitude, roughly coinciding with the -1.1 ° C isotherm in Labrador, the upper temperature boundary for permafrost."

Jan 1, 1982

By C. O. Swanson

Introduction It is thirty-odd years since I first entered the mining field by working underground at Anyox, which makes 1t clear that I can qualify as one of the older generation and claim the privilege of dealing in generalities and broad impressions. In this position I find it interesting to re~ view the salient changes that have taken place during the past quarter-century and indulge in some speculations concerning the future, with the hope that my comments may be of value to others engaged in the field of mining geology. As indicated by the title, the treatment is a perspective from a single viewpoint rather than an attempt to give a complete and impartial analysis. This plan, while deficient in some respects, has the advantage of being more specific than one based on .a. compilation of opinions. An additional advantage is brevity, which would be difficult to obtain on a subject of this scope if it were viewed from all angles. In conformity with the general plan, specific references to the literature have been avoided as much as possible, although a number of publications of general nature are listed at the end of the paper. This procedure is intended to give credit to the sources used without making them in any way responsible for the interpretation. The starting point for the discussion is the situation as it existed twenty-five years ago, when, as a recent graduate, I first had a fairly complete picture of it. However there is one impression of an earlier; stage that seems worth mentioning. In one of my first courses in geology the statement was made that some of the leading authorities of the previous generation, who guided geological thought at about the beginning of the century, were inclined to question the value of an association with mining. This attitude was no doubt exceptional, and certainly it was not adopted by the students who laid the groundwork for mining geology in North America. But its existence even in a limited circle is significant m showing how far the application of geology has advanced as the result of the investigations started during the first part of this century.

Jan 1, 1949

By B. A. Watters, G. A. Parslow, F. H. Mcdougall

Carbonate-rich rocks occur at several localities within the Flin Flon volcanic sequence of the eastern Amisk Lake area. The rocks occur in two areas: as a group of small occurrences on islands within Amisk Lake and as two much larger linear belts running parallel to the regional structure east of Amisk Lake. Mineralogically, the rocks consist of talc and Ca-poor ankerite with occasional graphite. Segregation of these minerals and colour variation impart a well-defined planar fabric to the rocks and where the units are fairly continuous (e.g. Mosher Lake), their trend and attitude suggests a concordant relationship to the volcanics. Major and trace analysis of22 samples confirms the presence of two types, with one type being represented in each of the two areas. Most of the elements studied can be used to characterize the two groups, but three elements in particular give a clear separation: Mg, AI and Ni. Recalculation of the major element analyses, on a water and carbonate-f ree basis, indicates that one group (large concordant bodies with high MgO, high Ni and low AI20.J is altered ultrabasic material of peridotitic or dunitic composition. Because no relict igneous material is observed, and the contacts are apparently very sharp, it is possible that the hydration-carbonization process occurred simultaneously with intrusion, .in a closed system. The other group (small occurrences with relatively low MgO, low Ni and high AI203J represents alteration of basaltic rocks. AIthough some analyses suggest the introduction of calcium, as carbonate, along with the volatiles, the major oxides have remained remarkably stable during the alteration process(es).

Jan 1, 1981

By K. D. Eng, W. T. Tierney

"During the past century, the development of vehicular transportation has benefitted tremendously from the performance improvement in engines in a situation where low-cost, plentiful fuel supplies were the order of the day. Engine advances were enhanced by and also dictated fuel modification to better adapt the energy source to the power plant.In discussing the several aspects of the change in approach from ""an engine and its fuel to a fuel and its engine"", the authors touch on the following areas:1. Description of an engine concept that provides the needed flexibility in fuel appetite at good efficiency to cope with future requirement s.2. The constraints placed on liquid fuel resource energy utilization efficiency by special engine-required fuel properties and the fuel efficiency of the various engine types available.3. Future vehicle engine fuel sources. This review will put into perspective the problem associated with the net energy available from future fuel sources under extensive research and development at present.4. A brief review of test data to show that fuel-tolerant and fuel-efficient engines are viable and that, in a fuel-resource-limited future, they can be a ""light at the end of the tunnel.""The Texaco Controlled Combustion System (TCCS)The TCCS is a unique means for stratified charge operation of an internal combustion engine in such a manner as to eliminate the requirement for octane or cetane number specification for the fuel. Octane rating is an empirical engine test method that evaluates a gasoline's resistance to spontaneous ignition or ""knock."" Cetane is based on a different engine test, which determines a diesel fuel's ease of spontaneous ignition . High cetane number enhances cold starting and permits high-speed diesel engine operation. As one would expect, the fuels in current use cover a band when the two values, octane and cetane, are plotted against each other."

Jan 1, 1982

By V. G. Minenko, A. L. Samusev

For efficient leaching of gold from sulfide ores and the oxidation of sulfides into sulfates, it is necessary to introduce a substantial amount of oxidant - atomic oxygen, hydrogen peroxide, ozone, potassium or sodium hypochlorite. In this paper, hypochlorite electrochemical treatment is proposed as an effective method of intensification of refractory ore leaching. The objective of the study is to increase the gold recovery from refractory ores with the application of chlorinated solutions that are modified by chemical or electrochemical treatment. The advantages of the use of the modified chlorinated solutions instead of cyanide for gold-sulfide leaching are considered to be the following: a high concentration of the oxidizing agent (hypochlorite ions) in solution helps to achieve a high speed of gold dissolution in the form of chloride complexes; the possibility to produce hydrochloric acid solutions that may be used for the recovering gold by electrolysis; the possibility of the processing of carbonaceous, arsenic-bearing and others kinds of refractory gold ores. The mechanism of the interaction of the modified chlorine solutions with gold-bearing sulfides (pyrite and arsenopyrite) was investigated. The efficiency of the application of chemical and electrochemical leaching method was proved. The main factor that limits the rate of gold dissolution is a high concentration of sulfate ions (SO4 2-) formed in the solution by the oxidation of sulfide minerals. The optimal parameters of chemical and electrochemical leaching method and effective ways to remove sulfate ions were determined. The method helps to increase the level of the gold recovery up to 87% from refractory ores. The intensification of leaching by chemical and electrochemical treatment opens up opportunities for the creation of modern efficient and environmentally-friendly technologies that may be applied for gold extraction from refractory gold ores.

Jan 1, 2016

Train on Different Equipment - * Immersive?s interchangeable cabin controls technology - ?clip on & off? * Change Simulator from one machine to another in minutes * No technical expertise required to swap * Real, functioning, controls and displays are used to aid rapid learning Immersive has produced a range of Conversion Kits to suit most equipment. Modular design - Easy to convert from one machine model to another with a Conversion Kit. Caterpillar Models Trucks - 769D, 773D, 777D Trucks - 785B, 789B, 793B Trucks - 785C, 789C, 793C, 797 Excavator/Shovel - 5130, 5230 Front end loader ? 992, 994 Dozer ? D10, D11 Komatsu Models Trucks - HD325, 785-5, 985-5 Trucks - 730E, 830E, 930E Dozers - D375A-3, D475A-3 Shovel - PC8000 P&H Shovels - 4100A, 4100XPB, 4100BOSS Hitachi Shovels - EX2500, EX5500 O&K Shovel - RH200 Bell Articulated Truck - B40C

May 1, 2003

Orebodies of the Renison Bell - Mt. Bischoff tinfield in Tasmania are stratabound, conformable lenses of massive cassiterite-bearing pyrrhotite, with underlying discordant, fault-fracture-controlled and more siliceous ore. The deposits occur in eugeosynclinal, trough-deposited sedimentary and mafic volcanic rocks which are stratigraphically equivalent to diff erentiated volcanic rocks that contain volcanogenic massive base metal sulphide deposits in a parallel arc to the east. Textures of the massive pyrrhotite ore suggest that it has undergone metamorphic recrystallization. Although the massive ore contains both monoclinic and hexagonal pyrrhotite, a study of a few samples from one orebody suggests that their distribution is stratigraphically controlled, with the monoclinic variety abundant only at the base. The distribution pattern of rare-earth elements in massive ore is similar to that of volcanogenic massive base metal sulphides in New Brunswick, and suggests that mixing of sea water with exhalative hydrothermal brines occurred during ore deposition. Tin is a common accessory element in many volcanogenic massive base metal sulphide deposits providing strong evidence that it, too, is transported and deposited by volcanic affiliated hydrothermal brines. Sedimentary rocks containing the massive orebodies are fine grained, thinly laminated, compositionally banded and of mixed chemical sedimentary-tuffaceous origin. They include finely recrystallized chert, carbonate-rich and pyritic varieties; and soft sediment deformation structures in these rocks suggest that dense sulphides deformed underlying, less dense chert prior to lithification. Close to ore the chert becomes massive and coarsely recrystallized, as does the carbonate, which is here strongly enriched in Fe and Mn. Apatite is present in pyritic, cherty and carbonate-rich beds and in the ore itself, in all of which it shows a similar pattern of rare-earth element distribution, suggesting that it is of marine sedimentary origin. These deposits have traditionally been considered as epigenetic replacements of favourable carbonate horizons by hydro thermal flu ids derived from later Devonian porphyritic intrusions. Some of these intrusions have associated tinbearing greisens. The above relationships suggest, alternatively, that, like massive base metal sulphides, the tin deposits were of original syn-sedimentary origin. Circulating hydrothermal brines generated during early Cambrian eugeosynclinal subsidence and tectonism rose through steep fault-fractures, there giving rise to the discordant orebodies, and were discharged on the sea floor, where the massive pyrrhotite lenses were precipitated with the associated cherts and carbonates. In some places, Devonian intrusions remobilized the earlier deposits, forming greisens and newepigenetic veins. Finally , the geologic selling of these deposits, in trough deposited sedimentary and mafic volcanic rocks, suggests another favourable environment for massive sulphide exploration which is quite different from the domal felsic volcanic environment so heavily favoured currently in North America

Jan 1, 1979

By Pierre Antoine Dhaiti, Gilbert Sergerie, Michel Dagbert, Jean-Maurice Brodeur

"Quality of iron ore is generally determined by several factors which can be correlated or independent. Among these f actors, we generally find per cent iron, silica, magnetite or hardness. Forecasting the short- and long-term fluctuations of these f actors in the future pit is an important feature of mine planning in these deposits. Computer simulation provides a realistic answer to these questions. It allows to generate values for the most important quality features of each shovel load with the proper correlations between them as well as between one load and the next being fully reproduced. Then different sampling schemes f or grade control or blending facilities can be examined on the simulated data. The mechanics of the simulation procedure and its potential applications are described in an example.IntroductionThe purpose of this paper is to illustrate the use of in-situ grade simulation in the planning o f the grade control in an iron ore min e. More precisely, given a production unit of given size, we need to know how many samples have to be collected in that unit so that we ca n recognize its grade with a reasonable precision. Conclusions that we would like to arrive at are of the type: with 4 blasthole samples we ca n get the iron grade of a 10,000 ton bloc k with less than a ± 2% Fe error 95% of the time.The approach t hat we take to solve this problem is simulation. We simulate the grade of samples and the grade of the block that contains these samples. We repeat the simulation for hundred s o f blocks. By comparing the sample grade with the block grade in each case, we determine the actual number o f blocks where the difference sample-bloc k is less than a given limit."

Jan 1, 1983

By E. Goodwin

"Maclaren Forest Products Inc.Lime is commonly used for the neutralization of acid, and the removal of heavy metals in mine waste waters. However, the precipitation of heavy metals as hydroxides must take place under conditions of controlled pH, to produce minimum concentrations of dissolved metals. An account is presented explaining the concepts applied to lime-treatment processes at Bell Mine during the period of a supernatant discharge to Babine Lake; October 18, 1982to January 25, 1983. IntroductionBell Mine of Maclaren Forest Products Inc., Babine Mining Division, an open-pit copper mine, is located on Newman Peninsula, Babine Lake approximately 65 kilometres northeast of the town of Smithers, British Columbia (Fig. 1).A depressed market for copper metal in 1982 forced a management decision to suspend operations at the mine for an indefinite period from October 3 I, 1982. For some time prior to the mine closing date, mine management was concerned about the increasing level of supernatant in the tailings pond , and its possible effects on the stability of the dam when cycloning of mill tailings ceased. Consideration of these potential hazards led to an application being filed with the Provincial Waste Management for a permit to discharge the excess water to Babine Lake. This large lake, an important link with several significant salmon spawning sites, is a major contributor to the British Columbia commercial fishing industry. Jurisdiction for the environmental affairs in the area is shared by the Department of Fisheries and Oceans, the Environmental Protection Service, and the Provincial Waste Management Branch. These agencies were directly concerned in the formulation of discharge permit following joint consultation, and exchange of information with the company on environmental concerns. An approval was finally granted to discharge approximately 1,000,000 cubic metres of supernatant from the tailings impoundment at Bell Mine into Hagan Arm, Babine Lake from October 18, 1982 with a daily discharge not to exceed 9000 cubic metres. Provisions were made that a particular discharge procedure be followed, and that the company would be responsible for setting up a sampling and monitoring program to safeguard the quality of the effluent."

Jan 1, 1986

By D. A. Stokes

"In October of 1980, Fording's 15 000-ton capacity clean coal silo was put into operation. The silo was unique in that it was designed to allow the mass flow of material, coupled with a sophisticated computer-controlled dynamic loadout/weighing system.On May 1, 1982, an explosion, attributed to a methane buildup, devastated the top of the silo. .As a contingent plan to minimize the effect of the production loss the conveyance to the silo top was reconstructed and the silo' was back in operation by mid-June 1982, although the silo top was left open to prevent further methane buildup. As dust emissions occurred during loading ofthe silo, an extensive study was undertaken to establish dust control for the silo, while at the same time providing methane detection and control.The study, conducted for Fording by the Cambrian Engineering Group of Calgary, involved an extensive search and investigation of existing coal silos. The study concluded that there IS no universally accepted method of controlling methane emissions in coal silos.The study also produced a unique conceptual design for handling methane, while at the same time, protecting the environment . Fording's Clean Coal SiloThe silo, located at Fording Coal's Fording River metallurgical coal operation, is utilized for the storage and load out of cleaned thermally-dried metallurgical coal.The silo was constructed in 1979 and 1980 to reduce unit train loadout times and to facilitate the handling of “special shipments"" of coal. The silo went into operation in October 1980, under manual control and utilized computerized, automated loading by February 198I.The silo is 21 m in diameter and 76 m high, with a nominal capacity of IS 000 live tonnes. The coal storage portion of the silo is 21 m in diameter and 48 m high, utilizing 2 steep-angled hopper outlets allowing mass flow of the stored coal during train loading. Each hopper has a control gate and a discharge chute, one chute for bulk loading, the other for trim loading of coal into the rail cars."

Jan 1, 1986

By Lucien Piché

"IN any opportunity such as I am now given, I suppose that one should not fail to say that what the world has to offer to this year's graduates in science and in engineering is the greatest promise ever held out. High-ranking new scientists and engineers -particularly those with the Ph.D. degree -find themselves in an apparently delightful situation; the glow of attention that surrounds them and the dazzling starting salaries that are offered to them may indeed be turning their heads a bit and the attitudes of some of them are sometimes expressed with a smugness that can find its equivalent only in freshmen. On the average, however, the new graduates are, without any doubt, the best trained ever, or at least they have been the most expensive to train in the universities.There appear to be exciting opportunities for competent, well-trained and educated scientists and engineers far beyond the numbers that can be annually produced, and the demands for excellence in depth as well as in breadth of training probably will continue to increase for many years to come. The problem is visible all around us in Canada that there is much more money to buy brains than there are brains to be bought."

Jan 1, 1966

By J. S. Stachulak

"IntroductionInco Limited operates nine underground mines on the rim of the Sudbury Basin. These operation s are situated near the city of Sudbury, 589 km west of Montreal, and 363 km north of Toronto. The ores are mined primarily for nickel and copper, and the principal minerals are pentlandite, chalcopyrite , and pyrrhotite. Total ore production from underground is in excess of 51 000 tons per day.The total volume of fresh air supplied to the nine mines is six million cu.ft/min. There are 50 main fans in operation at these mines, powered by electric motors totaling 11 200 kW (15 000 hp).The trend in metal mining during recent years towards mechanization and high-tonnage production methods has greatly increased ventilation requirements. The now of air must quickly dilute and carry away diesel exhaust fumes, dust created by mining operations, and the fumes of the explosives used in blasting. Mechanical ventilation is required to obtain the necessary volume and control, as natural ventilation pressures alone are, for the most part, inadequate and unreliable. In the event of a mine fire or other needs, close control of ventilation is essential.There are two unique heating systems presently in operation at Inco: Creighton Natural Heat Exchanger and Stobie Ice Stopes."

Jan 1, 1991

By C. Chapman, P. Cowx

"INTRODUCTIONTetronics Research and Development Co. Limited has installed several plasma torches for steel heating in continuous caster tundishes. An extensive demonstration program on a 14 tonne tundish reported the following advantages of plasma heating.• close control of steel temperature to ± 5°C;• a reduction of the furnace tapping temperature of up to 20ºC, leading to savings in energy and refractories costs ;• improvement in steel quality, to produce a slab product with an equi-axed crystal structure and a reduced number of large sub-surface slag inclusions;• the virtual elimination of oxygen pickup in the tundish; and• the capability of making ferroalloy trim additions to the tundish to permit a change of steel grade during casting, greatly decreasing inventory costs.The Need for Tundish HeatingIn the continuous casting of steel, the function of the tundish is to transfer the molten metal between the ladle to one or more continuously fed casting moulds. Figure I shows a typical temperature profile of molten steel in the tundish over the first cast cycle. It is observed that a rapid drop in temperature occurs both at the start of the cast, due to the tundish refractories absorbing heat, and also during ladle changeover. In addition, as a result of thermal losses through the ladle sidewalls, there is a gradual decline in the bulk steel temperature over the entire heat cycle. Consequently, in normal tundish operation, it is necessary to cast with a high superheat (25°C to 30°C + above steel liquidus temperature) in order to prevent freeze-up of the strand. Problems of high temperature variation and the potential of the steel solidifying in the tundish are greater for small caster units of low thermal mass . A high steel superheat increases the steelmaking vessel process time and refractory wear and prevents the formation of a uniform equi-axed solidification structure in the cast steel, resulting in centre line segregation and porosity. The large drop in the casting temperature that occurs during unsteady state operation causes an increase in the number of sub-surface inclusions, reducing the value of the product. Accordingly, plasma heating may be employed to maintain the molten steel at an optimum temperature to produce a slab of consistent quality."

Jan 1, 1989

By Carl Sonnen

Reading the newspapers, you will know that opposition to ratification on economic grounds always points to the view that action will result in major price increases for energy (to both industry and households) with consequent severe losses of energy production and a loss of competitiveness for energy-intensive producers (i.e., in your kinds of industries). You might think of this as the ?carbon tax? fear, and you should note that many of the initial policy development experiments included variations of this theme. Analysis reported in late 2000 and into early 2002 reported reductions in energy production in the long run of between 10% and 20%. At the upper end of that view, these were the kinds of numbers reported in the Industry Canada study ?leaked? to the Press last week. The consequences of this approach included significantly uneven negative effects for some provinces (e.g., Alberta, but also Saskatchewan and Newfoundland). It had been agreed by the First Ministers of Canada, however, that the policy should not yield those results so development in recent months has focused on eliminating sector and therefore provincial ?sore thumbs?. Although an emissions trading system, which represents this type of approach and directly impacts costs of production, continues to be featured in the new or current policy and is applied to the Minerals Industries among others, it is designed to be implemented in such fashion that the costs are more moderate than before. And because the industries covered by permits are almost all price takers, there is no device for moving an increased price signal forward to ?consumers?. What this does do is even out negative effects among sectors in the economy and for provinces, but at the expense of government financial results.

Nov 1, 2002

By W. W. Muir

"The Baker Mine used a 100-ton per day conventional cyanide leach mill located in northern British Columbia. A production decision was made in early 1980 and the mill was on fine in April 1981.Ore reserves had been estimated at 100,000 Ions averaging 0.9 oz gold per ton and 18 oz silver per ton . Mineralization consists of electrum (Au/Ag) and acanthite (Ag2S).This paper will review plant design and focus on some problems associated with start-up and early operation with the intention of assisting other mine operators by indicating potential problem areas.IntroductionThis paper will discuss operating strategies employed at Baker which improved over-all mill performance. Also included are some ideas which could be steps toward a more efficient operation in a similar setting.Actual dore production by mine life was 37,606 oz gold and 742,117 oz silver.Figure 1 illustrates the relative stability attained over the mine life. Metal recoveries for gold and silver were 92% and 85% respectively.Safety at Baker was of prime importance because of its remote location. Baker received the Mine Safety Association ""Small Mines Award "" in two of its three operating years. At shutdown in late 1983 the mill had operated for over 850 days without a lost-time accident."

Jan 1, 1985

"One of the corporate values mentioned by many companies deals with respect for people. This paper discusses one aspect of this value, namely, the need for clarity of accountabilities and authorities. The job of the manager in achieving this goal is analyzed and the benefits of enhancing the manager-employee conversation outlined. IntroductionCorporate values usually refer to the standards of behaviour that the leaders of the organization expect of all employees, including themselves, in carrying out their duties. Terms such as integrity, respect for the individual, continuous improvement, continuous learning, teamwork, speed, and innovation are quite common. The company-specific values are typically developed by the top executives of the company, and then tested with a broader group of employees. Where the process works, employees have a good understanding of what behaviour is expected of them in doing their work, in making difficult decisions, and in interacting with others.Having spent considerable time in his career investigating and studying the management systems at over 50 of the most successful companies in Canada, the United States, Europe and Japan, the author has had the opportunity to visit organizations such as Hewlett-Packard, 3M, Xerox, Intel, Toyota, NEC, Komatsu, British Airways, and Eastman Chemical. These experiences, together with the work of many other researchers, including the work of Dr. Elliott Jacques, have helped significantly to form the thoughts expressed below.Rather than reviewing the creation of corporate values and their deployment through the organization, these remarks focus on issues over which managers and employees have some control. The value in which managers can have significant impact deals with people and the respect shown them in the workplace. The component of respect to be emphasized is to be clear about expectations or accountabilities for oneself and the people who report to you, and to ensure that personal authority matches those expectations."

Jan 1, 1999

By A. M. Girodo

"Dorbyl Heavy Engineering has been manufacturing winders since 1949 mostly for the South African mining industry.Table 1 shows that the vast majority of winders have been double drum winders. At the greater depths with larger ropes being employed, it became apparent that multi-rope winders would be needed. The high stress variation in Koepe winder ropes at great depths especially beyond 2000 m, ruled out this possibility. Thus the original concept was borne for the Blair multi-rope winder where the stress level variations in the rope would be as per the well known, tried and tested double drum winder. The Blair multi-rope was also devised to increase payload by using multiple ropes.With the increasing costs of transporting men and material coupled with fact that orebodies are getting deeper, various feasibility studies have been carried out by South African mining houses. For this reason Dorbyl Heavy Engineering has done conceptual design work of both double drum and Blair multi-rope winders with diameters up to 8.5 m dia (still well within our manufacturing capabilities). These feasibility studies have looked at depths approaching 4000 m*.This paper covers the typical duties leading to the choice of single drum, double drum, Koepe and Blair multi-rope hoists on South African gold mines. A brief synopsis of Dorbyl hoists in use in the South African mining industry, with some indications of future trends, will be discussed.With current installed depths of wind approaching 2500 m, the Blair multi-rope hoist has been used extensively for the heavier payloads.Some of the main considerations pertinent to the design of the Blair multi-rope hoist are illustrated together with the implications of using this type of hoist to winding depths of3000 m to 4000 m in the foreseeable future."

Jan 1, 1995

Weekly Capacity ? Current Schedule Rate (198.5 tonnes / hour) X Skip Time (112.7 hours) X Effectiveness (85%) = Weekly Capacity (19,015 tonnes) Capacity Conclusions - Existing hoists optimized are best option for Fraser Morgan (>20M + schedule for other). - Peak will have to be managed. - Critical to have equipment & infrastructure in best possible condition to ensure reliability.

Feb 1, 2008