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By Michael R. Yenchek

The U.S. Bureau of Mines investigated the operational characteristics of spliced portable power cables. This research had a dual purpose: (1) to determine the thermal and mechanical performance of repaired trailing cables and compare them with undamaged cables and (2) to gauge the impact of long-term, localized heating on the insulating and jacketing materials contained in cable splice kits accepted or approved by the Mine Safety and Health Administration. The ranges of splice joint resistance and tensile breaking strength were determined from laboratory measurements. The choice of crimping tools affected the strength of the splice under tension. Thermal profiles of energized spliced cables were constructed, which showed that spliced conductor joints operated 5 to 20°C hotter than the intact cable at rated currents. Accelerated life tests of thermally aged samples of splice kit insulation and jacket materials confirmed a deficiency in the thermal rating of the insulating tape. The recommendations in this report may be utilized to revise splice kit design, splice kit approval criteria, and trailing cable loading guidelines. Characterizing the thermal operating limits of spliced trailing cables may help to minimize the associated risks from explosions, fires, personnel burns, and shock.

Jan 1, 2010

By Donald J. Frendzel

The post-World War II expansion of the Soviet petroleum industry has established the U.S.S.R. as a major oil-producing nation and has led to Russian reentry into the international petroleum trade. The rapid growth of Soviet petroleum production will allow the U.S.S.R. to displace Venezuela as the world's second largest oil-producer in 1960 and to narrow further the gap between Soviet and U.S. crude-oil production. U.S.S.R. crude oil output was only a tenth of U.S. production in 1946, but it will be more than a third at the end of 1960 and more than half in 1965. The Soviet Seven-Year Plan (1959-65) for oil provides for substantial increases in petroleum production, refining, storage, and distribution facilities. Crude oil production and primary distillation capacity are to double, considerable storage capacity is planned, and pipelines for crude oil and petroleum products are to increase threefold. According to the Soviets, the initial phases of this plan (1959 and 1960) have been completed successfully. However, this progress has been achieved with difficulty.

Jan 1, 1961

By PáDeáBosscher, A Bruwier, M Weidenbach, C Philippe, T Ly, A Van Den Bosch

In the mining business the cost of grinding media represents up to 40 per cent of the total milling cost and therefore grinding media optimisation has a direct impact on the concentratorsÆ bottom line. In the process of optimising grinding media alloys, Magotteaux developed its own methodology which consists of a series of analyses, tests, calculations and evaluations and assist the concentrator in optimising their processes.This paper presents the Prominent Hill case study where this methodology has been applied on both the secondary ball mill and regrind IsaMill«.The analysis of the wear conditions in the secondary ball mill allows Magotteaux to select a series of grinding media alloys to be tested to reduce grinding media consumption. By marking these different grinding media types with a unique drilling pattern, one can quantify the relative wear performance and cost effectiveness of each grinding media type within the same milling environment. After selecting the most economical grinding media composition a full scale industrial trial, involving topping up the selected grinding media is carried out and the media wear performance closely monitored and analysed.For stirred grinding mills, suppliers propose different grinding media, mainly ceramic beads, with specific properties and cost. Therefore the concentratorsÆ choice is a compromise between grinding efficiency, wear resistance and cost. The selection of the correct grinding media for stirred milling and the assessment procedure will be presented in this paper. The test results of the new stirred grinding media type in the regrind IsaMill« at Prominent Hill are presented and analysed.CITATION:Weidenbach, M, Van Den Bosch, A, Bruwier, A, Ly, T, De Bosscher, P and Philippe, C, 2012. Forging ahead - A collaboration between the OZ Minerals Prominent Hill Concentrator and Magotteaux to improve plant performance, in Proceedings 11th AusIMM Mill OperatorsÆ Conference, pp 105-110 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 29, 2012

By N. Del Bel Belluz

Drilling underground in the Grasberg De-watering drifts has routinely hit water aquifers with high flow rates and pressures. Two types of holes are utilized; pilot-holes to probe ahead of the tunnel development to intersect aquifers ahead of the face; and de-watering holes to de-water rock formations that will drain water from the Grasberg pit and allow tunnel development to proceed safely. Recently, rates of 1050 psi static pressure have been recorded with flows from a NQ hole measured at 1350 gpm (US). The water flows can be slightly acidic, necessitating the use of stainless steel collar gear to resist corrosion. These rates were anticipated and contingencies were planned early to deal with these conditions. The collar gear is used to control water flows whereby the water is treated as an important resource. As a result, pm has established procedures to maintain safety of the drill crews, enable coring of the rock and to maintain safety of the miners who are driving the drifts.

Jan 1, 1998

By Tamas Kekesi

Anion exchange in HCl media is considered an efficient alternative to the combination of the conventional purification methods. Anion-exchange distribution functions have been determined for cobalt and the main impurity elements by the technique of batch equilibration. Results were confirmed by spectrophotometric investigations and elution tests. Based on the new and the available distribution functions, combined with the assessment of thermodynamic stability, a procedure of anion exchange separation has been devised to eliminate virtually all the impurities from the cobalt-chloride solution. Separation of copper has been enhanced by the introduction of a preliminary step under reduced conditions. The rest of the impurities are eliminated in a second anion-exchange step applying rinsing and elution stages under oxidized conditions. The optimum parameters of the procedure have been determined according to performance characteristics (purification ratios, yields and volume efficiencies) derived from the analysis of elution curves obtained with laboratory scale ion-exchange columns. Special computer programs have been developed to facilitate thermodynamic simulation, analytical correction and data processing.

Jan 1, 2003

By Edmund S. Leaver

The selection of a process for treating a gold ore is governed primarily by the characteristics of the ore under consideration. The form in which the gold occurs, its mode of association with other minerals, and the size and surface condition of the gold particles are important factors which influence materially the choice of procedure for recovering gold. A knowledge of these characteristics may be obtained by microscopic and chemical methods combined with experimental testing. Cyanidation and amalgamation, either alone or in conjunction with flotation and gravity methods, are peculiarly adapted to the treatment of gold ores, especially those of relatively low grade. Gold alloys readily with mercury provided both present clean surfaces. The presence of oils and grease, antimony and arsenic minerals, or soluble sulphides have a harmful effect. Very small, flaky particles of gold frequently are lost in amalgamation because of noncontact with the mercury. Fine gold in pyrite, or gold having rusty or contaminated surfaces, is often lost for the same reason. Grinding or some form of abrasion sometimes removes surface films of iron oxide or substances of a similar nature, and alkalies or other chemicals are used to remove grease. Gold is readily soluble in cyanide solution, and this method of treatment is particularly effective in the recovery of gold from the tailings resulting from other types of concentration procedure. Cyanide solutions must contact the gold to insure recovery, and the porosity of the ore treated and the fineness of grinding required are important governing factors. The use of lime in cyanidation is necessary to protect the cyanide, to precipitate undesirable substances, and to settle slimes. Certain substances in ores are harmful in cyanidation; chief among them are those that combine with cyanide, forming cyanides, and carbon which precipitates gold from solution. Arsenic and antimony are also harmful if present in sufficient quantity. These and other difficulties encountered in cyaniding certain ores often are overcome by roasting prior to leaching. Zinc dust is used almost universally for precipitating precious metals from cyanide solutions. The refining and melting of the product may be accomplished by oxidizing the zinc before melting it in graphite pots with fluxes, although sulphuric acid is now used largely to remove the zinc before melting. Straight cyanidation practice is being replaced by flotation as a major process, followed by cyanide leaching of the tailings, but amalgamation is still needed as a primary process for the recovery of coarse gold before either flotation or cyanidation.

Jan 1, 1935

By Riley S. J

The basic aim of mine planning is to design mine layouts and schedules that achieve optimisation of operations, minimum cost and maximum resource recovery. Successful accomplishment of this aim is facilitated by timely and comprehensive rehabilitation planning commencing at the pre-feasibility stage and continuing until the end of mining. Incorporation of a final landfomt design for waste rock dumps in a mine plan requires a prediction of surface stability, which may be achieved through erosion modelling. Erosion prediction models can be placed in two broad categories: soil loss prediction models eg USLE and CREAMS, and geomorphic models such as SIBERIA. A waste rock dump landform design based on selected slope form and grade and drainage systems should be developed as part of planning. A digital terrain model (DTM) of the landfonn should then be produced which can be modelled for long-term erosional stability using pre-determined parameter values. If acceptable standards of stability are not achieved, the landform should be redesigned and remodelled until the desired result is obtained. The planning process incorporating models requires knowledge of spoil or waste rock properties and model parameter values. This information is site specific and can be obtained from drill cores or costeans at the pre-mining stage and from spoil or waste rock during the mining stage. Realistic model parameter values are critical in post-mining landfonn design and can be obtained by several methods, including rainfall simulation, monitoring, geochemical analyses and grain size analysis.

Jan 1, 1994

By Heinrich Ries

Fullers' earth is a clay-like substance, which has the property of decolorizing or clarifying oils. An ultimate chemical analysis shows it to differ from most ordinary clays in having usually a high percentage of combined water and a low amount of alumina. There is probably a large amount of hydrous silica present. Fullers' earth possesses little or no plasticity, and in order to work properly has to be ground very fine. A chemical analysis is of little value at present in determining its quality; only a practical test suffices. Up to about two years ago all of the fullers' earth used in this country was imported from England; but about that time deposits were discovered in Florida, "† and since then rumors of its occurrence have been coming from all parts of the country. Next to the Florida deposits of fullers' earth, those of South Dakota are the most extensive thus far discovered in this country. The earth was first discovered near Fairburn, Custer county, and other deposits have since been prospected at Argyle, Minnekahta and other localities. Fairburn.—One of the first deposits located and opened up is five miles southeast of Fairburn, Custer county. The mine is a mile from the Fremont, Elkhorn and Missouri Valley Railroad, and the section exposed shows, beginning at the top: Feet. Micaceous sandy clay,......... 6 Fullers' earth,..........9 Micaceous sandstone,......... The fullers' earth passes upwards into the sandy clay, but in its purer portions it is a yellowish, gritty clay, with a somewhat

Jan 1, 1898

During the first five years of operation, the Lihir gold mine has steadily increased plant throughput rate to over 4 Mtpa, well above the original design capacity of 2.8 Mtpa. Understanding how future variations in ore type impact on plant performance has been an integral part of LihirÆs development program. This paper discusses the key drivers for significant improvements to the plant, including a second oxygen plant, a pilot flotation plant, an autoclave heat recovery circuit, a pebble crushing circuit and additional autoclave feed pumping capacity. The result is a process plant with the flexibility to accommodate variations in ore type without significant loss of throughput.

Jan 1, 2003

By Mark Jolly, Nasim Soleimanian

"During the last 20 years CFD (Computational Fluid Dynamics) has been used as a tool to aid furnace designers and manufacturers to improve energy efficiency and effectiveness of glass furnaces. However as the models are maturing the effect of feeding equipment used to push the raw material into the furnace has not been included in the process models. This paper investigates the effects of batch pattern in the melt space caused by charging equipment on the energy efficiency of the furnace focusing on the melting zone. A simple batch patterns sensitivity study has been performed using purpose built software (Glass Furnace Model-GFM). It is concluded that in order to further reduce the energy consumption of the furnace it is necessary to model the batch charging process in more detail to find more opportunities for improvement.Introduction Glass manufacturing is a conservative industry which applies to all the four major segments (float glass, container glass, fiberglass, and specialty glasses). Risks due to the high capital investment, very long service life of the furnaces, and the demand for high performance and quality from the outset translates into evolutionary progress rather than revolutionary. The main problem facing glass manufacturers are the financial cost of manufacture, its impact on the environment, and mounting pressure imposed by the authorities for greener manufacturing and reduction in emissions.The main energy intensive activities involved in continuous glass manufacturing are: the need for high temperature to create and maintain the viscous flow, homogenisation of glass melt (melt residence time), and maintaining the two to achieve continuous output of glass at the right quality. The high temperature and long duration of homogenisation has resulted in the design oflarge furnaces, which have high energy consumption, low specific performance, and high C02 emissions. As an example in the container glass sector the most efficient furnace has a specific primary energy consumption of 3.8 GJ /tonne of glass at a level of 50% cullet in the batch. Even very small improvements in efficiency by optimising operation would have a high impact [1-14]. Given the conservative nature of the industry and the costs involved in experimental data gathering, CFD modeling of the process has been used extensively during last two decades to not only improve our understanding of the process but also as a tool in predicting possible optimisation windows, e.g. Glass Furnace Model ( GFM), a commercially available piece of software that has been developed to optimise furnace operation."

Jan 1, 2013

By C Moorhead, J Jones

A common problem in the mining industry is that company geologists can operate in relative isolation to the rest of the company (Jones and Moorhead, 2011). This may result in poor knowledge transfer and often priority conflicts with geology, operations and project departments. This problem is amplified by the acquisition of mineralogy capabilities and other metallurgical (met) test work undertaken by many companies in order to solve for complex orebody problems. Met data is often not located and viewed in 3D space so that geologists and engineers can create and work with geometallurgical (geomet) models (Bye, 2006). Visualisation of data in an interactive graphical 3D model provides a bridge enabling met professionals to collaborate with engineers and geologists to provide a common understanding of the relevance of geomet data.In recognition of this problem, Newcrest has undertaken an effective collaboration strategy to improve internal and external engagement through the use of large visualisation displays (Jones, 2009). The displays are underpinned by IT systems and information management practices that recognise the needs of underlying disciplines. Today it is generally understood within Newcrest that this is required to improve decision-making, deliver faster cycle times and improve governance.Collaboration in companies has been generally associated with the introduction of new IT functions (IBM, 2008). However, the science and engineering process that are used to structure modern IT-based collaboration systems and practices are now known to be simplistic compared to the long-standing practices associated with collaboration and knowledge management in disciplines such as geology and mining.CITATION:Jones, J and Moorhead, C, 2013. Geometallurgical communication as a distributed information system, in Proceedings The Second AusIMM International Geometallurgy Conference (GeoMet) 2013 , pp 133-138 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 29, 2013

By S. A. Allen

The Eufaula bauxite district of Barbour and Henry Counties in southeast Alabama covers an area approximately 14 miles long, 6 miles wide at the eastern extremity near the Chattahoochee River, and 10 miles wide at the western end near the east fork of the Choctawhatchee River (see figs. 1 and 2). The long axis of this polygon bears a little south of east.

Jan 1, 1949

By C. M. Campbell

IN 1934 Newfoundland, after extravagant operation based on exaggerated ideas of what she had to work with, became bankrupt, ceased to be a self-governing Dominion, and passed into the hands of a Commission. Since the days of Dawson, Canadians have been taught that no country in the world is as rich as their own. This idea has become a religion; contrary views are heresy, and are suppressed even by technical organizations and government departments. Following the alleged habit of the ostrich, we have buried our heads in the sand and have refused to face the facts. This policy of "to have today and to hell with tomorrow" is now bearing fruit. After forty years of operation on the basis of unlimited natural wealth, with resulting over-expansion, wholesale depletion of capital assets, and huge borrowings, we are, now that our wealth has been shown to be very limited, face to face with the status of Newfoundland. Already, in this Province, commission government of bankrupt municipalities is not uncommon. The ostrich is referred to as the most foolish bird in the world. That is not the case-no ostrich ever hid his head in the sand. In the clear air of his home on the South African veldt, an area characterized by low bushes, he is a conspicuous object. When danger approaches, he lowers his head; matches his background, the bushes; and danger passes him by. This leaves the Canadian, with his head still in the sand, to fill the r61e cast for the ostrich. Fortunately, a few Canadians never did get their heads covered; others are getting them out far enough to see what is going on. Their comments are very much to the point. "Nowhere in the world," says Mr. Meighen, "has more harm been done to any country by an exaggeration of its resources and potentialities than has been done in Canada'.

Jan 1, 1941

By Alexander N. Winchell

"THE MICHIGAN COPPER DISTRICT.Location. The copper mines of Michigan are all in the north¬ern part of that state on the Keweenaw Peninsula, which extends from the (Michigan) mainland for about seventy miles northeast¬erly toward the middle of Lake Superior. The mines occur in a belt or zone occupying the central portion of the peninsula from end to end.. The most productive mines for many years past have been those located not far from the city of Houghton in' the central part of the zone, in a section extending about ten miles southwest of Houghton and fifteen miles northeast. The most important mines in order of.location, from the northeast to south¬west, are the following: Mohawk, Ahmeek, Allouez, North Kearsarge, Wolverine, South Kearsarge, Centennial, Calumet. and Hecla, Osceola, Franklin, Quincy, Hancock, Isle Royale, Superior, Baltic, Trimountain, and Champion. The first three named are in Keweenaw county and all of the others are in Houghton county. Still farther to the southwest are the Lake, Mass, Adventure, Michigan, Victoria, and White Pine mines. These are in Ontonagon county.History. The exploitation of these copper mines extends back into prehistoric times. There is little evidence that the American Indians carried on mining operations in this region in the period shortly before the advent of white men, but there is abundant evidence that the ancestors of the Indians, •or some earlier inhabitants of the region, carried on primitive mining operations. For example, Mr. S. O. Knapp, Agent of the Minne¬sota Mining Company, in the winter of 1847-48, made the first discovery of prehistoric mining. This event is described as fol ,lows by Foster and Whitney : Location: As shown on the accompanying map, the Mar-quette district extends from the region of Marquette on Lake Superior westward for about forty miles. The main basin of the district is only about three to six miles wide, but outlying areas which are commonly regarded as belonging to the same mining unit, make the north and south dimension of the district about twenty miles. The most productive portion of the area is in the vicinity of Negaunee and Ishpeming, .about ten miles from Mar¬quette, but important mines are found also all along the range as far west as Michigamme and also to the south in the fold known as the Republic Trough. Comparatively recent developments indicate that important ore bodies have been developed in the outlying Swanzy district about eighteen Miles nearly due south of Marquette.The Marquette Iron District.History: The first discovery of iron ore in the Lake Supe¬rior region was probably that made in 1844 near the site of Ne-gaunee by the government surveying party in charge of William A. Burt, sent out under the direction of Douglass Houghton. This surveying party was using a solar compass, invented by Mr. Burt, and noticed variations in the direction of the magnetic needle at various times and places, but. on the 19th of September, while running the east line of Township 47 North, Range 27 West, the needle varied from its normal position until it stood nearly at right angles thereto."

Jan 1, 1920

By E. Emami, J. Valencia, J. Sattarvand

The knowledge of the final location of a drillhole is critical in obtaining the expected blasting results. This paper proposes a new methodology to control the drilling accuracy in open-pit mines using aerial images and machine learning. Specifically, it investigates how support vector machines (SVM) and convolutional neural networks (CNN) are useful for automatically detecting blastholes over drone images captured in blasting patterns. Several datasets were obtained from different mines in Nevada (USA) and were used to train and test models. We then processed those images to create orthomosaic and digital elevation representations of the patterns. Thousands of patches were then extracted and augmented to develop SVM and CNN models. The results demonstrate that machine learning is useful for drillhole detection and, in this way, to control the drilling accuracy and use the explosive energy more efficiently.

Sep 1, 2021

By M J. Noy

The automated measurement of rock fragmentation particle size distribution in the muck during muck excavation has been developing over the last 16 years. The introduction of stereo camera imaging of the muck has provided improved automated particle segmentation for image-based measurement algorithms. Recently, a new vision system processing algorithm has been developed. The inclusion of 2D texture in the analysis has provided a significant improvement in the definition of the finer size fractions, which has resulted in the automated analysis no longer requiring calibration.The previous stereo vision system algorithm required analysis calibration to account for poor ‘small particle’ definition in the 3D surface profile. This was because of the depth perception limitations of the stereo camera system at greater than 8 m. The new algorithm has been implemented on a number of shovel-installed vision systems, and the algorithm’s performance in automated analysis has been assessed against a diligent manual analysis of the same fragmentation images. The new algorithm provides improved distribution resolution and accuracy.CITATION:Noy, M J, 2015. Evaluation of a new vision system algorithm for automated fragmentation measurement from a shovel, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 721–726 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

By V. Ramachandran

In view of the increasing environmental regulations that have been promulgated in the last 30 years, non-ferrous smelters and refineries have learnt to handle effectively the process waste streams that need to be bled from the system for impurities' control The cations of concern are copper, lead, zinc, cadmium, mercury, thallium, nickel, silver, sodium and potassium. Anionic species of arsenic and selenium also need to be addressed, Sulfates and chlorides-not a major concern at present-have come under scrutiny in the recent past. The current paper reviews several treatment options with reference to a) types of waste streams processed b )process chemistry c)discharge options and recovery of treated water and d) sludge disposal The long term goal of any smelter and/lor refinery should be to achieve zero liquid discharge from the plant. Methods to obtain zero discharge are discussed.

Jan 1, 2003

By Toru H. Okabe

As part of a systematic study on the thermodynamic properties of complex nitrides, phase equilibria of the system Li-M-N (M Mg, AI, Ga) at 900 K were investigated. An attempt to determine the thermodynamic properties of complex nitrides was made by using the galvanic cell method, which utilizes LiMgN as an electrolyte under nitrogen atmosphere. The electromotive force (Emf) of the cell at temperatures between 800 and 1100 K was measured. While the Emf of the cell at 900 K was measured to be 0.137 V, data discrepancies of ±0.03 V were found. It was difficult to determine temperature dependence of the Emf. The Gibbs energy change for the reaction, 113 Li3N (s) + 1/3 Mg3N2 (s) = LiMgN (s), at 900 K was determined to be !'J.Go, (LiMgN) = -13.2 (±2.9) kJ/mol. Using thermodynamic information on the binary nitride from literature, the standard Gibbs energy of LiMgN was derived to be !'J.Go f (LiMgN)= - 121 kJ at 900 K. The thermodynamic stability range of nitride was discussed by constructing isothermal chemical potential diagrams that provide a better understanding of the stability region of the LiMgN phase. The diagram was found to be in good agreement with the isothermal phase diagram determined by the alloy equilibration method. Although the obtained data includes large uncertainties, the results provide a better understanding of the thermodynamic stability of nitrides. The potential application of this complex nitride to nitrogen chemical sensors or a medium for controlling nitrogen potential is also shown.

Jan 1, 2003

By P. T. Bissert, T. J. Lutz, J. A. Yonkey, G. T. Homce

"Underground refuge alternatives (RAs) require an air source to supply breathable air to the occupants. This requires pressure relief valves (PRVs) to prevent unsafe pressures from building up within the RA. The Mine Safety and Health Administration (MSHA) mandates that PRVs prevent pressure from exceeding 1.25 kPa (0.18 psi or 5 in H2O), or as specified by the manufacturer, above mine atmospheric pressure when a fan or compressor is used for the air supply. Research to date by the National Institute for Occupational Safety and Health (NIOSH) suggests that the design and implementation of PRVs used in RAs has not yet had sufficient performance analysis or technical development. In response to this need, NIOSH tested a variety of PRVs using an instrumented test fixture consisting of data acquisition equipment, a centrifugal blower, ductwork, and various sensors to determine if subject PRVs meet the MSHA requirement. Relief pressures and flow characteristics including opening pressure and flow rate were measured for five different PRVs under a variety of conditions. Subject PRVs included two off-the-shelf modified check valves, two check valves used in MSHA-approved built-in-place (BIP) RAs, and a commercially available valve that was designed for a steel RA and is currently being used in some BIP RAs. The test results showed relief pressures ranging from 0.20 to 1.53 kPa (0.8 to 6.1 in H2O) and flow rates up to 19.3 m3/min (683 SCFM). INTRODUCTION The Mine Improvement and New Emergency Response Act of 2006 (MINER Act) was enacted in the wake of three mine explosions/fires that claimed 19 lives that year. Intended to help improve underground coal mine accident preparedness, the MINER Act includes provisions that target mine safety issues in areas such as emergency response planning, adoption of new technology, training and education, and mine safety standards enforcement [1]. Section 13 of the MINER Act specifically directed NIOSH to provide for research into the effectiveness and viability of refuge alternatives (RAs) for underground coal mines. This mandate culminated in the 2009 adoption of changes to 30 CFR mining health and safety regulations, requiring underground coal mines to provide mine emergency RAs and associated components, to provide a life-sustaining environment for persons trapped underground. Such RAs can be either self-contained mobile units or built-in-place (BIP) facilities. The regulatory changes also include provisions establishing requirements for Mine Safety and Health Administration (MSHA) approval of RAs and their components, and among these provisions are numerous criteria for providing a safe breathable atmosphere under positive pressure within the RAs. One specific criterion for maintaining a safe RA atmosphere requires the inclusion of an air pressure relief valve that will activate at a maximum of 1.25 kPa (0.18 psi or 5.0 in. H2O), or at a pressure above mine atmospheric pressure in the RA as specified by the manufacturer when the breathable air is supplied by a fan or compressor [2]."

Jan 1, 2017

By P. J. Finnis

This paper describes the use of wire rope on open-pit mining equipment, giving specifications and examples of the performance achieved. Installation methods are also discussed, making the paper of considerable practical use to mine operators.

Jan 1, 1973