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By Samuel W. Woods

The Tacoma, Washington plant is one of six plants in the United States Gypsum Company's Acoustical and Mineral Fiber Division. The Tacoma facility was acquired in 1959 along with six other mineral wool plants from the American Rock Wool Company. Originally, the Tacoma plant was built as a carbide plant during the Second World War and after that was converted and operated as a mineral wool plant by several insulation companies. Through these early years, the use of raw materials at Tacoma consisted primarily of slags along with small percentages and various combinations of silica (in various forms such as gravel), limestone and basalt. These raw materials were melted in cupolas using coke as the heat source. Raw material usage and types as well as mineral wool production methods and equipment remained without major changes for many years.

Jan 1, 1983

By Shan Mafi

he Broken Aro coal mine is located at the Woodbury Wildlife Preserve 11 km (7 miles) west of Coshocton, OH on State Route 541. Underground min¬ing at the 16-hm2 (40-acre) site took place during the 1910s. During the past five years, surface mining has occurred along the western and northern perimeters of the underground region. The Ohio Department of Natural Resources (ODNR), R&F Coal and American Electric Power (AEP) are involved in a project to remine the abandoned underground complex. The program also includes installing a mine seal made of fixated flue gas desulfurization (FGD) material. Previous mining activity in this area has resulted in an acid mine drainage (AMD) problem on portions of the reserve. In particular, a prominent AMD source is present in the Simmons Run drainage. The project goal is to eliminate or reduce the AMD that is discharging into the watershed. It was initially hoped that the Simmons Run drainage area could be economically mined. Accordingly, this area was included in the mine permit. However, experience with other previously mined areas on this reserve showed that the old mine workings were more extensive than originally thought. Old mine workings present several problems. The most significant are reduced coal recovery, poor coal quality and AMD liability. All of these problems increase mining costs. And the more extensive the old workings, the more significant the increase in cost. Based on R&F's experience with old mine workings in this area, it was decided that economic recovery of the Simmons Run drainage reserve was not possible. As a result, R&F excluded the Simmons Run drainage area from its early mine plans. Some time after it was decided not to affect the Simmons Run drainage area, R&F and ODNR's Division of Mining and Reclamation discussed the possibility of removing this area from the permit and attempting to correct the AMD problem as an Abandoned Mine Lands (AML) project. Specifically, the discussion centered around mining through a portion of the old mine workings to expose the mine openings in the highwall. Once exposed, the mine openings would be sealed using FGD material from the nearby Conesville power plant operated by AEP. In addition, there was interest in reclaiming the old tipple and associated gob pile located adjacent to Coshocton County Road 17 on the opposite side of Simmons Run. R&F attempted to eliminate the AMD problem by sealing the mine openings with FGD material. Once the seals were installed, they were covered with overburden. Monitoring wells were installed to determine the effectiveness of the seal and the inundation progress in the old mine workings as well as monitoring the quality of ground water. The project was jointly funded by revenue from the sale of the coal recovered during the project and AML funds. The FGD seal is expected to cause well water levels to increase above preseal elevations. However, the additional head pressure due to increased water depths in the underground mine may cause seepage through the bottom of the mine or out through the perimeter. The in¬creased water depth in the underground mine is expected to cause lower oxygen concentrations in the underground mine water. Since acidity is produced by oxidation of iron pyrites, less oxygen should result in better quality water. Monitoring wells will be installed before seal installation so that pre- and postseal water levels and well water quality can be determined. Surface sampling locations will be identified. These will be monitored before and after seal placement.

Jan 1, 1998

By J. M. Keane

Critical to successful dump and heap leaching for copper is an adequate testing program for evaluation of the applicable parameters. This paper deals with testing methods to establish best conditions for dump and heap leaching of copper so that commercial operations can proceed on a rational basis. Discussion is also offered of ore occurrences suitable for dump and heap leaching.

Jan 1, 1985

By Joseph L. Walker

INTRODUCTION In looking over the diversity of the papers that are being presented during this meeting on The Industrial Practice of Fine Coal Processing one cannot help but be impressed with the progress the industry has made in beneficiating fine raw coals, and in the number of innovations that are under study to increase recovery and to improve the quality of the finest size particles produced at a preparation plant. Those who are not in our industry, who look at the technical program, might be confused, when they see that the papers include such topics as cleaning to zero and heavy media cyclone cleaning 28M x 100M; application and performance of fine coal jigs, tables, hydrocyclones, spirals, and flotation; filtration, dewatering and thermal drying; and ancilliary aspects such as fines handling, instrumentation and process control plus screening and liberation. This is an observation and not a criticism of the diversity of papers being presented. The program fits within the parameters of fine coal preparation as the term "coal preparation" is defined, but perhaps not as the term "fine coal" is defined. Admittedly these definitions are sometimes loose. However, each should be made more definitive if a meaningful fine coal preparation overview is to be possible. COAL PREPARATION DEFINED In the opinion of the writer, the term "coal preparation" should be defined as including all work activities that are performed on all components of a run-of-mine coal from the time it leaves a surface reserve or an underground portal, until all components are either ready for shipment or are stowed on, or in the earth in an environmentally acceptable manner. This definition excludes the work that is performed to improve coal quality or handleability inside the mine or pit. This work is commonly called "face" or "pit" preparation. FINE COAL DEFINED The term "fine coal" means different things to different people. In the past, anthracite finer than No. 3 Buckwheat (3/16 in.) was considered fines which often were discarded from the breaker as an unsalable by product; and bituminous coals finer that about 1/4 in. (slack) were either discarded or sold at cost to prevent an accumulation of "no bills" which referred to a product having no immediate sale. Although a standard definition of "fine coal" is yet to be accepted by the industry, a designation of coals by particle-size range has evolved through the wide use of three-circuit flowsheets, wherein the optimum size range by washer type determines the size fractions: a coarse-coal circuit for the plus 3/8 in., a -11- coal circuit for the 3/8 in. x 28 Mesh, and a fine-coal circuit for the remaining 28 Mesh x 0. Logically, the term "fine coal" should refer to some resultant size fraction or some top size by zero. This definition should include a 28 Mesh x 0 feed to a flotation cell but should exclude a 28 x 100 Mesh size fraction fed to a heavy media cyclone. Failure to include the resultant sizes in the definition precludes accounting of the full range of particle sizes present in the feed to the plant. Since the 28 Mesh x 0 fraction is treated in the final circuit of the three discreet washing circuits, now almost always used in U.S. commercial applications, and since it contains all of its resultant sizes, in the writer's opinion, it should be designated "fine coal". FINE COAL CLEANING Cleaning coal fines, which in the past was at best marginally profitable, is now an essential part of coal preparation strategy for a number of reasons : 1. Raw coals now cost more to produce and

Jan 1, 1988

By Ronald Allum

Underground copper mining at Magma Copper Company's San Manuel Mine has been un going since 1955. The block caving mine has been producing copper ore at the rate of over 16 million tons per year. Depressed market conditions during the 1980's forced Magma to look at new technology. Late in 1984, Magma began testing new equipment and mining methods at the underground mine at San Manuel, Arizona. The tests resulted in a move towards mechanized production using new procedures and equipment. The goal was to increase efficiency and cut costs through mechanization.

Jan 1, 1988

By V. P. Petrov, V. S. Znamensky

There are a great number of asbestos deposits in the USSR, and some are quite large. The main deposits of chrysotile asbestos are shown in Fig. 1. The Bazhenovo deposit, which is located in the Sverdlovsk region, is the largest and has been mined since 1889. Systematic studies of asbestos deposits were begun from the very be- ginning of Soviet government and are most often connected with the names K.E. Tarasov, P.M. Tatarinov, B.J. Merenkov, N.D. Sobolev, F.V. Syromjatnikov, V.N. Lodochnikov, V.P. Petrov, V.P. Eremeev, L.A. Sokolova, V.R. Artemov, and V.F. Dybkov. Investigations by these people and others helped the USSR be one of the most important producers of asbestos in the world. In this chapter, the main asbestos deposits of the USSR are explained in a general outline from the point of view of their genesis, common features, and differences that must be taken into account for forecasting, exploration, and the mining of asbestos. All chrysotile asbestos deposits of the USSR were formed from magnesium rock as a result of comparatively low grade temperature, hydrothermal alteration, and free crystallization of fibrous chrysotile in open cavities that served as catalysts. Chrysotile, a widely distributed rock-forming mineral, is not in general an important mineral for industry as it is a long fibrous and main vein variety. However, it must serve for geologists as an important prospecting criteria. And, the geologist should search for the mineral not only in places of possible chrysotile generation, but in places where asbestos may be crystallized in its long fibers. The Soviet geologists distinguish chrysotile asbestos deposits in two groups: (1) ultrabasic rocks and (2) sedimentary dolomite terranes, taking into account how the maternal rock was affected by hydrothermal solutions. The largest deposits are related to ultrabasite. In dolomite, the largest deposits are small and their asbestos contains almost no iron, which makes it a better filler for insulating plastics. There are a few types of asbestos deposits within the limits of the ultrabasic group, the largest being a Bazhenovo type to which the deposits of the Urals are attributed. This Bazhenovo asbestos is characterized by the most complete zonality of disposition for various kinds of asbestization. These types of deposits are, for the most part, the only ones presently working in the USSR. The Bazhenovo deposit is connected to the gabbro-peridotite intrusive belt that is about 180 km long and is broken into a number of fault blocks as shown in Fig. 2. Granitoid veins of intruded rocks are found along the deepest faults, and were sources of hydrothermal solutions that affected the maternal rock. The nearest granitoid vein, ultrabasite, is substituted by listwanite that consists of quartz, talc, carbonate, and some other essentially talcous rock. The next zone of hydrothermal alteration is composed of serpentine. The boundry between serpentinite and unaltered ultrabasite is as irregular, diffuse, and rough as the boundaries between all other zones. Nearer the vein of granitic rock, ultrabasite is entirely serpentinized into massif serpentinization that penetrates through cracks and fissures. There is an unaltered ultrabasite space between fissures, and the biggest block is preserved unaltered in the central part of the massif. The Soviet geologists call this ultrabasic sopka. Preservation of the unchanged blocks is of great importance for deposit formation as volume changes are impossible during the process of asbestization and serpentinization. It may be confidently said that asbestization in Bazhenovo type deposits is possible only when alteration of ultrabasite has not completely occurred. Under conditions of massif volume, a very big mass of substance must be carried out of the ultrabasite for the progressive stage of serpentinization. However, in the regressive stage,

Jan 1, 1986

By Egon Pohl, Friedrich Steinhäusler, Werner Hofmann

INTRODUCTION Anticipated increase of nuclear fuel production in the future coincides with growing concern about the occupational health risk of miners from inhaled radon decay products. As a consequence it has been suggested to even lower presently permitted exposure levels (NIOSH, 1980) and implement more stringent control on measurement programmes. Compliance with these regulations requires large investments in new or modified ventilation systems as well as in increased expenditure for staff and instrumentation for health physics operational monitoring. Since both costs are directly related to the overall ore production costs, this can have far reaching implications with regards to the economic feasibility of certain mining operations and consequently reduce estimates of low-cost minable ore reserves. In addition there is increasing evidence that the radon problem is not limited to the nuclear fuel cycle only, but can also represent a significant hazard to non-uranium miners. A key component in the cost-effective implementation of legislative control measures is the monitoring system employed. The choice of system is decisive for the total costs of installation and maintenance, manpower requirements and accuracy of nuclide determination. In the following operational specifications are defined for monitors in mining and milling environments. Different types of available instrumentation are discussed with regard to their suitability for practical radiation protection in underground mines, open cut mines and mills. ATMOSPHERIC CHARACTERISTICS Underground mines Radon in the air of underground mining operations is exhaled from surrounding rock surfaces, crushed material and, to a lesser extent, from water seepage. Whilst in uranium mines radon releasing ore bodies are generally localized in distinct areas, radon sources in non-uranium mines can be very dispersed throughout the system of mine tunnels. The ventilation scheme used influences the absolute atmospheric level of radon as well as the equilibrium conditions between radon and its decay products (factor F). In uranium mines mechanical forced-air ventilation is normally the only way to achieve and maintain legally required nuclide levels. This causes the F-factor to be rather low, e.g. in French CFA-mines F is of the order of 0.2 (Francois, Pradel, Zettwoog, 1975). At the same time the fraction of unattached radon decay products (fp) can increase due to the high air velocities employed. However, it is possible to find non-uranium mines with either natural draught ventilation only or assisted on demand by forced air ventilation during special operations or climatic conditions. Thereby the F-factor is more dependent on seasonal changes of temperature differences between outdoors and mine atmosphere and work routines. As a result F can cover a wide range from 0.02 to 0.95 (Steinhäusler, 1976). The use of filters or electro-precipitators in mine ventilation systems can modify the atmospheric characteristics twofold as it generally decreases the content of radon decay products, but at the same time increases the content of the unattached fraction fp . Average concentration levels of radon decay products are mostly lower in mechanically ventilated non-uranium mines than in equally ventilated uranium mines and are below 0.3 Working Level (UNSCEAR, 1977). However, some working places in non-uranium mines, specially with only natural draught ventilation can occassionally approach maximum permissible levels as defined for uranium mines (Strong, Laidlaw, O&apos;Riordan, 1975; Snihs, 1976; Sciocchetti, Scacco, Clemente, 1981). Open pit- and surface mines Radionuclide levels of radon decay products in the atmosphere of these mines are mostly too low to represent a significant inhalation hazard for miners, ranging typically from 0.03 to 0.1 Working Level (Steinhäusler, 1976). However, personnel using airpurifying respirators or working in cabins ventilated with filtered air can be exposed to a radon atmosphere with low value for the F-factor (F [<] 0.1) and high fp-value up to 80 % (Leach and Lokan, 1979). Mills Atmospheric radon concentration in crushing, grinding, drying and packing sections depends on the radium 226 content of the ore, ore storage methods and ventilation system employed. Providing adequate ventilation ([>] 2 air changes per hour) and control of dust production radon and its decay products represent only a minor problem (Saconney, 1979). MONITORING OF OCCUPATIONAL EXPOSURE Objectives Operational monitoring of the working places provides information on: - confirmation of appropriate control of the routine mining methods employed - indication of abnormal conditions. Although this type of monitoring enables the location

Jan 1, 1981

By Akram Marseet, Andrew J. Petruska, Rik Banerjee

Event cameras are used for their performance in high dynamic-range lighting conditions which are canonical to active mining environments. Direct labeling of event-based image data to train a model to perform semantic segmentation using traditional methods is slow and error-prone. This study proposes a framework to use roughly hand-labeled color images from a mine as an input to an intermediary probabilistic algorithm called alphamatting to generate a ground-truth data set. These high-fidelity labels can be used to train a semantic segmentation model to differentiate the support strap from the roof. This model can then be leveraged to segment an event-based scene to enable autonomous roof bolting. This pipeline has been shown to achieve an accuracy of 88% with a false positive rate of 3%.

Feb 1, 2024

By Yuan Le, Dominic Reda, Vojtech Ernst Gall, Kurt Zeidler, Tomasz Kecerski

High Speed 2 (HS2) mandated that Building Information Modelling (BIM) processes be implemented during design and construction. Gall Zeidler Consultants (GZ) was responsible for developing the BIM Models for the portals, tunnels, and cross passages of the of the 16 km-long Chiltern twin-bore Tunnel. In addition, GZ developed the GBR for the Chiltern Tunnels and incorporated the relevant information into the Project’s BIM framework. This paper presents the implemented BIM framework, describes the modelling approach, and discusses the advantages and challenges of implementing BIM, particularly how BIM improved interface coordination and how BIM was used in feasibility assessments of different construction options.

Jun 13, 2023

By J-M M. Rendu

Geostatistics are increasingly recognized as powerful tools for reserve evaluation and grade control. It is also generally accepted that geologic input is required for the results of a geostatistical study to be meaningful. The role of the geologist is significant at all stages, whether it be to oversee the creation of the database, to assist in the statistical and semivariogran studies, to ensure appropriate block evaluation and kriging, or to review the results obtained. However the link between geology and geostatistics is often complex and not well understood. A presentation is made of the areas where geologic input is needed, and of the tools which the geologist should have at his disposition to ensure that his role is fulfilled. Organization of a Geostatisticel Study To be acceptable as the basis for financial investment, a geostatistical reserve estimation should be composed of four phases, the last phase being optional: Phase 1 - Background discussions, Phase 2 - Computation, Phase 3 - Reserve reporting, Phase 4 - Reserve audit. During the background discussions (Phase 1) the role of the geologist is primordial, as it is then that most decisions will be made concerning the geologic factors to be included in the geostatistical model.

Jan 1, 1985

By O. A. Bascur

In recent years, metal-producing companies have increased their investment in automation and technological innovation, embracing new opportunities to enable transformational change. Transformation to a digital plant can fundamentally revolutionize how industrial complexes operate. The abundant and growing quantity of real-time data and events collected in the grinding and flotation circuits in a mineral processing plant can be used to solve operational issues and optimize plant performance. A grade recovery model is used to identify the best operating conditions in real time. The strategy for increasing the value of instrumentation in current plants is reviewed. An optimal Gaudin size distribution model provides augmented information from traditional sensors to find the optimal grind cut size to reduce metal losses in the flotation circuits. Sensors in flotation circuits enable an estimate of the recovery and determination of the optimal froth depth and aeration using an air hold up flotation model. A strategy of classifying data for on-line generation of insights to using operational intelligence tools is described. The implementation of a recovery/grind strategy with industrial examples in non-ferrous mineral processing is presented.

By T. A. Gray

The environmental liabilities of coal waste disposal sites can have a major impact on a mining project&apos;s economic viability. Developing a waste disposal site is no longer simply an exercise in completing paperwork to obtain a permit, with the proliferation of environmental regulations in recent years, managing disposal sites now requires design creativity, short term and long term planning and detailed monitoring to maximize the benefits to the mining company. Operating costs and future capital costs for expansion of existing sites, new site development and regulatory compliance should be reviewed periodically and considered in the overall management plan. This paper discusses various management methods that are being employed in the industry to improve waste disposal operations both environmentally and profitably.

Jan 1, 1994

By J. D. Noll, J. A. Organiscak, A. B. Cecala

Over the past decade, a substantial effort has been made to improve the air quality inside enclosed cabs of both underground and surface mobile mining equipment to reduce respirable dust exposures by the equipment operators. As part of this effort, the U.S. National Institute for Occupational Safety and Health, (NIOSH) completed a comprehensive laboratory study that determined the significant factors for cab filtration and pressurization systems. From this information, a major underground mining equipment manufacturer designed a filtration and pressurization system that was incorporated into the enclosed cabs of its equipment. A long-term evaluation was performed on the effectiveness of this filtration and pressurization system to improve the air quality in the enclosed cabs of two different pieces of equipment, a face drill and a roof-bolter machine, at an underground limestone mine. This long-term evaluation demonstrated a significant reduction in dust levels between outside-to-inside cab respirable dust concentrations. During this evaluation, a modification to remove one of the filters on the roof-bolter machine simplified the design without sacrificing the system’s efficiency. Tests using particle count instruments performed during nonproduction time periods on both pieces of equipment indicated protection factors greater than 100 when comparing respirable-sized dust particles inside the enclosed cab relative to outside.

Jan 1, 2012

By W. Hu

Gravity concentration has been the main method for tin ore beneficiation, based on the significant difference of density between cassiterite and gangue in the tin ore. However, with the exhaustion of rich and coarse reserves, the proportion of tin distribution in slime be-comes as high as 50 to 70% and has a size range of -19 urn. In some sulfide tin ore, most of the tin is of the minus 10-urn size fraction, and thus slime processing has gained importance in tin ore processing. Some innovations are being developed, such as the centrifugal cone separator, belt concentrator, slime table, B-M separator, and slime flotation. Direct flotation with tolyl arsonic acid has been practiced with success.

Jan 1, 1989

By R. J. Smith

Hornestake&apos;s Mclaughlin Mine is the first commercial application of pressure oxidation pretreatment of gold prior to cyanidation. Inherent to the autoclave process are several liquid/solid separations. Flocculant consumption represents a significant portion of the consumable reagent costs at McLaughlan. This paper focuses on the efforts of the Operating, Metallurgy and Engineering groups to improve thickener operation and minimize flocculant consumption. An operating philosophy incorporating feed solids control, increasing flocculant dilution water and minimizing flocculant solution shear has resulted in a reduction in 1986 flocculant costs of $0.054/t ($0.06 st) versus 1985 costs. Additional changes are projected to result in a further cost reduction of $0.20/t ($0.22/.st) in 1987.

Jan 1, 1988

By D. S. Ramey

In-situ leaching of the oxidized copper mineral resource at the San Manuel mine has proven to be a technically and economically viable method of copper extraction. Although this leaching method has been modeled to predict future production capabilities, the expected magnitude of the ultimate recovery from any portion of the present mine is not fully understood. A closely controlled test has been designed, constructed, and is now operating to determine the rate and magnitude of copper recovery. The test, initiated in June 1992, is scheduled to operate for approximately 18 months. This paper presents an overview of the test design and current results.

Jan 1, 1993

By Daniel Lum

The limestone resources of Hawaii are derived chiefly from emerged fringing coral reef and coastal dune deposits of Pleistocene age. These deposits are most abundant on the island of Oahu and other older islands and least abundant on the island of Hawaii, the youngest. Their origin and depositional environment were influenced by glacio-eustatic rising and falling of sea levels during Pleistocene time. Dredged reef limestone deposits from two deep-water harbor projects have provided additional resources. Limestone uses include cement and lime manufacturing, concrete sand and aggregate, mad base material, beach sand replenishment, agricultural lime and golf course construction.

Jan 1, 1982

By MANZOOR ALI BROHI, IZHAR MITHAL JISKANI, Atta Ur Rehman, SHUAI HAN, MUHAMMAD TARIQ, NIAZ MUHAMMAD SHAHANI

The analysis of mine safety indicators using a scientific method can improve mine safety and assist management in making informed decisions. This research establishes a mine safety evaluation index and proposes an integrative evaluation model based on the entropy weight and grey clustering methods. The index consists of 27 indicators classified into seven criteria: working environment (A), miners’ attributes (B), safety policies and education (E), prevention and control (F), and monitoring and supervision system (G). Using Pakistan’s mine safety situation as a case study, the proposed model categorized the indicators into five safety levels (very low, low, medium, high, very high) for the present situation and for their relevance in terms of future safety improvement. The results show all of the criteria falling into the very low level for the current mine safety situation. Three of the criteria — C, E and G — are identified as having very high levels of significance for future safety improvements.

By A. B. Cecala

Video technology coupled with datalogging exposure monitors have been used to evaluate worker exposure to different types of contaminants. However, previous application of this technology used a stationary video camera to record the worker?s activity while the worker wore some type of contaminant monitor. these techniques are not applicable to mobile workers in the mining industry because of their need to move around the operation while performing their duties. the Helmet-Cam is a recently developed exposure assessment tool that integrates a person-wearable video recorder with a datalogging dust monitor. these are worn by the miner in a backpack, safety belt or safety vest to identify areas or job tasks of elevated exposure. After a miner performs his or her job while wearing the unit, the video and dust exposure data filesare downloaded to a computer and then merged together through a NIOSH-developed computer software program called enhanced Video Analysis of Dust exposure (eVADe). by providing synchronized playback of the merged video footage and dust exposure data, the eVADe software allows for the assessment and identificationof key work areas and processes, as well as work tasks that significantlyimpact a worker?s personal respirable dust exposure. the Helmet-Cam technology has been tested at a number of metal/nonmetal mining operations and has proven to be a valuable assessment tool. mining companies wishing to use this technique can purchase a commercially available video camera and an instantaneous dust monitor to obtain the necessary data, and the NIOSH-developed eVADe software will be available for download at no cost on the NIOSH website.

Sep 1, 2013

By S. Frimpong, E. Siami-Irdemoosa, S. R. Dindarloo

"Electric and hydraulic shovels are the dominant loading machinery in surface mining operations. Despite their critical role in production and their high capital and operating costs, no reliable and comprehensive quantitative performance metric is available. In this paper, a stochastic shovel effectiveness (SSE) measure is proposed for the purpose of quantifying the performance effectiveness of these shovels. The SSE is based on the widely used method of overall equipment effectiveness (OEE) in the manufacturing industry. The OEE measures the performance effectiveness of equipment by multiplying its mechanical availability, utilization and production quality. In manufacturing processes, quality rate is the ratio of the total number of products minus the number of defective products – equivalent to the number of acceptable products – to the total number of products. The SSE similarly uses the mechanical-availability and utilization terms, but instead of quality rate it uses a new parameter named bucket rate.The variability or randomness of the input data, that is, availability, utilization and bucket rate, are further incorporated into the SSE, and a final stochastic SSE distribution is derived in the form of a probability density function. One hydraulic and one electric shovel in a surface mining operation were selected to test the validity of the proposed method. The SSE scores for the two shovels, operating continuously for one year, were derived and compared. As with the OEE, the three-parameter SSE method yielded more representative results for overall performance measurement than a single-parameter approach. Using Monte Carlo simulation, a three-parameter Weibull and a normal distribution were derived for quantifying the overall effectiveness of hydraulic and electric shovels, respectively. As a decision aid, the proposed methodology promises to render a more informative tool than traditional metrics for mine equipment maintenance and management."

Jan 1, 2015