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By M Lewis, A Cook

This paper is based on the technology and functionality of a Modular Mining IntelliMINE« system which is a real-time decision-making tool. The IntelliMINE« system, incorporating Dispatch, is a fully Integrated Mine Management System. Measuring, quantifying and analysing the performance of mining is considered a fundamental and strategic step towards changing the nature of technical and operational decision-making at the majority of international mining corporations. Successful implementation of electronic data capture devices and computerised tools have enabled many mining operations to improve their competitive position with an improvement in the utilisation of the key assets, mineral resources, capital mining equipment and human resources. Real Time Mine Management Systems are designed to direct the emphasis away from collecting data and focus decision makers on the real issues with well-presented and reliable information. The systems provide a common stream of information to enable senior management, operations, maintenance, technical and process plant staff to make complementary decisions based on reliable, accurate and timely data. The mine asset information tools focus all employees on performance and give them feedback on their area of responsibility. The resulting tangible benefits can be delivered in different forms depending on the mining method, ore type, workplace culture and the current competitive position. Typical areas of improvement reported by system users are:reduction in capital expenditure on mining equipment fleets; more effective planning and budgeting parameters and procedures; increased control over ore-extraction and processing; increased employee accountability and organisational performance; and improved co-ordination between planning, operations, maintenance and processing. These improvements can be delivered in different forms depending on the status of the mine and commodity markets. In times of market oversupply and low commodity prices, the benefits can be delivered to the bottom line in terms of reduced cash costs, reduced capital and operating resources to maintain constant production. In times of market expansion, existing capital resources will be more productive delivering increased production and revenue. Mine management systems have the potential to transform a traditional mine operation into a learning organisation with an improved understanding of the critical performance issues and enable development of relevant strategies to continually identify and eliminate operational inefficiencies. The effectiveness of each strategy and operational change can be accurately monitored and its success (or otherwise) will be quantified. The latest downturn in the world metal prices has forced many mining companies to focus on cost reduction and productivity improvements as a means of remaining competitive. Maintenance represents a significant proportion of the overall operating costs in the mining industry. A structured proactive maintenance approach such as Reliability Centered Maintenance (RCM) can achieve significant cost reductions and productivity improvements. Remote condition monitoring systems are becoming increasingly commonplace and have the potential to identify problems prior to failure. Detection of equipment degradation prior to failure will enable repairs to be scheduled, thereby reducing costs and interruptions to production.

Jan 1, 2000

Legislation introduced for Queensland and New South Wales Coal mines provides different levels of prescription regarding specification of mine seals û generally in relation to capacity to withstand overpressure. In Queensland, the Coal Mining Safety and Health Regulation (2001), Section 341 (d) places a further onus on the statutory ventilation officer to æensure all ventilation control devices at the mine are properly constructed and maintainedÆ and that the ventilation officer æmust ensure a ventilation control device mentioned in the regulation à and installed at the mine meets the design criteria statedÆ for the ætype of deviceÆ. Based on the experience of the author, it appears that risk management and life cycle approach to seals has not been adopted to the same extent as for other aspects of operations. Further, because of the number of disciplines and personnel involved that may influence various factors affecting seal integrity, the opportunity for oversight or unclear allocation of responsibility is considerable. While suppliers can provide explosion or design rated seals, this should only be a starting point for application of the product in a coal mine. Application is often considered by mine planning staff (taking into consideration mine environment parameters such as water, control of gas, spontaneous combustion risk, etc) in conjunction with the colliery ventilation officer, and then construction completed by contractors under supervision of operational staff. After construction, seals often are managed by operational personnel with input from the ventilation officer. Input of the geotechnical engineer into pillar design, roadway opening size, ground support specification and most stable seal location is also required. The need for a customised design approach for each seal site is proposed in order to take into account the many and variable factors that may influence a site so that improved seal performance reliability and predictability can be developed. A program of quantitative as well as qualitative monitoring of performance and triggers for rectification or maintenance action is required, and would provide support to the aforementioned proposal. Many mines rely on visual/audible inspection and periodic bag sampling as the primary means of assessment. Other significant factors such as seal material properties, rib degradation, convergence, floor heave, effects of water on both structural integrity of the seal as well as the air tightness of the seal do not generally receive the same level of attention. Based on the above observations, the author has compiled a reference checklist in regard to the above matters, including aspects of and approaches to mine and pillar design, geotechnical modelling and data collection, civil engineering design, site evaluation and practical options available.

Jan 1, 2005

By W. Hodge Caraway

This report presents the results of an evaluation of several indirect methods of measuring the water content of oil-reservoir rocks. The water content of oil-base cores is considered to be most nearly representative of the water content of the undisturbed petroleum reservoir and therefore, the direct method of measuring the volumes of water in cores cut in oil-base drilling fluid was adopted as a standard for comparison. The indirect methods evaluated included (1) displacement through a semipermeable membrane by air, (2) centrifuge, (3) evaporation, (4) mercury injection, (5) chloride dilution and (6) electric logs. Approximately 270 samples of cores from petroleum-reservoir rocks were used in the study. The cores, most of which were cut with oil-base mud in the hole, were taken from oilfields in California, Texas Gulf coast, Colorado, Oklahoma, and Alaska.

Jan 1, 1959

By J. W. Allen

This report reviews the work performed on Task M of Bu-Mines Contract H0220073 to develop an engineering model of a surface and subsurface communications system for normal mine operations and for post disaster rescue operations. The system concept provides for one-way transmission of digital information between a number of identifiable subsurface terminals or subcenters and a single surface station. It also provides 2-way voice communications between the subcenters and the surface station. The basic communications link is electromagnetic signaling through-the-earth, but the system is also capable of using mine phone lines as an alternate link. Engineering models of three subcenters and one surface terminal (see Figure 1-1) have been fabricated in order to demonstrate the system's performance. The system concept, however, permits up to 20 subcenters to be incorporated if desired. Additional subcenters are also feasible for large mines if they can be deployed in the mine to operate on a noninterfering basis.

Jan 1, 1973

By A. Monomakhoff

If a conductor traversed by an electric current is broken, a conduction forms in the air between the two broken ends of the wire. This conduction manifests itself in an initial phase by an electric spark and, in a second phase, by an arc if the the circuit continues to supply sufficient power. This arc goes out when the distance between the two ends of the conductor becomes sufficiently large. If the break occurs in an explosive atmosphere, the energy contributed by the arc can cause an explosion. To avoid such accidents, electric circuits that may be utilized in hazardous atmospheres can be made "intrinsically safe". The investigation which we conducted is part of a research project on the intrinsic safety of arcs of high intensity but short duration, in the case of resistive circuits. We developed an electronic system which makes it possible to limit the duration of an arc at the level of the break of a conductor traversed by a current with a possible maximum intensity of 80 amperes. This experimental device for monitoring and measuring the parameters of the arc has shown that arcs of high intensity but with a duration limited to a few microseconds do not ignite an explosive methane-air mixture.

Jan 1, 1975

By J. P. Bennett, K. S. Kwong

Slagging gasifiers are used to produce chemicals and/or electricity from feedstocks such as coal and/or petroleum coke. A gasifier environment includes pressures from 400 to 1000 psi, temperatures from 1250-1550°C, are cyclic, reducing gases of CO and 112, and molten ash that interacts with the refractory liner materials. The high Cr2O3 refractory liners of gasifiers fail within 3 to 24 months. Gasifier users seek materials with increased reliability and service life. This paper discusses causes of refractory failure and efforts to increase refractory service life.

Jan 1, 2004

The successful operation of diesel equipment underground does not entirely depend on selection of robust, reliable, easily maintained machines. Results are also heavily influenced by the following factors: Design and condition of the operating area. Skill of operators. Correct maintenance facilities. Experience, skill and initiative of maintenance personnel. If the mine layout does not allow access to a central workshop area, the effect of any shortcomings will be magnified. The best results will only be obtained by close co-operation between mining and maintenance departments right from the initial planning stages.

Jan 1, 1977

By Tim Wolf

The paper "Weld Notch Affects on Pulley and Belt Conveyor Reliability" has done an excellent job of describing theoretical fatigue and fracture mechanics methods used in modern weld design. From this foundation, we intend to further detail areas previously discussed and present new research in the application of these principles to pulley weldment life prediction. Affects of changes in alternating stress range, mean stress, and residual stress have been investigated using controlled laboratory fatigue tests on a pulley weldment. Comparisons between these results, weld codes, and theoretical fatigue predictions will be made and discussed.

Jan 1, 1998

By C Fenton

The mining industry is a relatively minor user of water, which has historically been largely soured from private schemes. Frequently mines are often located in areas with limited available water resources. Water reform is increasingly affecting access to water for new mining projects and mining companies are being required to consider the value of water and the implications of reliability in their planning. This paper seeks to briefly review the water reform process in Australia and how it is affecting the mining industry with reference to some recent project experience.

Jan 1, 2003

Mine planning for ore recovery by open stoping and pillar recovery is becoming more sophisticated, but there are basic operating constraints which must be imposed if this planning is to realise the production results on which the mine is dependant. The production reliability of an open stope is usually a high priority and common design problems can be identified. A range of practical considerations which should be considered at the mine planning stage are reviewed including equipment performance, blasting technology, ventilation requirements, development layouts, lead time, ground conditions, support, backfilling and ore recovery.

Jan 1, 1982

By K. D. Allen, M. J. Blattman

The problem of measuring the amount of rock removed during a given time interval is faced by most mining operations. Many methods have been developed with varying degrees of success, dependent upon the mining method and the availability of usable data. The Rosebud Mine has been in production for nearly two years, employing several techniques to estimate monthly production from underground production stopes. The use of three-dimensional solids generated from survey data has greatly improved the reliability and confidence of monthly production reports. The authors will summarize the methodology currently being utilized at Rosebud.

Jan 1, 1999

By Jack Hayes

Vibrating wire strain gages have proven to be a very reliable and effective tool for the measurement of strains associated with the loading of bored piles (drilled shafts). However, when these strains are used to calculate the load, or stresses in the pile, the results can sometimes be confusing and/or difficult to interpret. This paper describes some of these situations, using examples from actual case histories, and discusses some of the difficulties associated with residual load effects, curing and temperature induced strains, load stress distribution effects, estimated modulus and area.

Jan 1, 2002

By Carl Verholek

Remote control systems for industrial applications have advanced since the early 20 years, increasing its capabilities by utilizing new electronic technology. This electronic “tool” has benefited many mining operations, making them a safer place to work and at the same time more productive. Almost any operation that presently uses a man at the controls of the machine or using a wired tether control, is a candidate for improvement by the addition of a remote control. Remote control systems add safety, reliability and productivity at a cost that is usually recovered in mere months after installation.

May 25, 1998

By Tim A. Beattie, John R. Grant, David L. Kennedy

After many years of research, ICI staff have developed a numerical modelling system for the study of detonator/primer/explosive configurations. Results from this work clearly identified that current primer designs were not as effective in delivering their energy potential as needed. Alternative designs were evaluated and several prototypes, all essentially spherical in shape, were built for testing. Results have shown a significant improvement in various aspects of primer performance, including omni-directional pressure transferral and increased energy release rates. Reliable, high performance priming of explosives is now achievable for a much wider application range.

Jan 1, 1991

By J. M. Czaplicki

The problems connected with deep mine hoisting and the increasing complexity of this process can be analysed through the application of such mathematical tools as stochastic modelling to study the effectiveness, reliability or safety of hoist methods. To relate these theoretical investigations to real practice, knowledge about components, their stochastic nature and stochastic order of appearance is necessary. This paper presents results obtained during the ten-year (1976-85) period of research undertaken in the Polish mining industry by the Mining Mechanisation Institute of the Silesian Technical University, Gliwice, Poland.

Jan 1, 1987

By Simon T. Johnson

Potential applications for boom tunnelling machines requires reliable assessment of in-situ performance. The majority of existing classification schemes concentrate on the prediction of excavation rate, neglecting the important influence of tool consumption rates. A statistical approach is taken to the analysis of the performance data, which was obtained first-hand through in-situ monitoring, and laboratory testing of representative rock samples. A statistical discrimination technique is used to produce a scheme for the prediction of performance groups, each of which covers a limited range of cutting rate and/or tool consumption rate.

Jan 1, 1984

By Sue W. Wells, James J. Moore, Stephen D. Lynch, R. Hunter White

This paper describes the products and services that Phelps Dodge Corporation desires from solvent extraction reagent suppliers and the partnering relationship that Phelps Dodge wishes to develop with these suppliers. Product topics include: 1) manufacturing concerns, 2) product and process quality control reporting and 3) reagent customizing to meet individual plant needs. Service subjects include distribution, delivery time, emergency re-supply, terms, and tailoring technical support. The partnering relationship discussion reviews mutual benefits, communications, reliability, cross-functional teams for problem solving and developing new opportunities, and long-term commitment.

Jan 1, 1994

By E. Topuz

Mining equipment, like all other equipment, is subject to failure. Since most failures occur at random and are unexpected, corrective maintenance is usually more expensive and causes more down-time than preventive maintenance. In order to reduce the number of failures and thereby increase the availability of an equipment or system, preventive maintenance can be scheduled at predetermined points of time. The preventive maintenance scheduling policies presented in this paper utilize reliability and probability theories. They can be applied to various production bottlenecks where high cost equipment precludes having sufficient quantities of stand-by units.

Jan 1, 1982

By Robert F. Droullard

The U. S. Bureau of Mines (USBM) has investigated instrumentation and methods for measuring exposure to radon daughters in underground mine atmospheres. Both personal and area monitors have been studied through in-house and contract research. A field study in uranium mines identified some reliability problems that required additional work for the personal dosimeter systems. Improved versions of continuous working level detectors have been developed and tested for use as area monitors in underground mines. Test results for the personal and area monitors were satisfactory for underground mine applications.

Jan 1, 1981

By S. L. Zhu, Brij M. Moudgil, J. L. Pinault

Prompt neutron activation probe (PNAP) was evaluated to determine chemical composition of phosphate rock slurry in-situ. The technique was able to precisely analyze Ca, Si and H using a 252Cf source. Direct measurement of P and Mg was not accurate due to interference by the rare earth elements associated with the Florida Phosphate Rock. The solids loading, particle size distribution and flotation reagents present in the slurry had no significant effect on the accuracy of the measurements. The technique was found to be reliable also under industrial conditions.

Jan 1, 1993