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By Diogo Barcellos Moraes

O trabalho surgiu mediante a necessidade de reduzir o tempo de paradas do equipamento de laminação a frio por ruptura de fio maquina durante as reduções nos passes de laminação. Para que não ocorra ruptura do fio máquina durante as reduções nos passes, faz-se necessário uma boa lubrificação do fio maquina antes de iniciar o contato do mesmo com os anéis de laminação e para que isso ocorra de forma eficaz o fio maquina deve estar completamente seco antes de passar pela caixa de lubrificação. Sendo assim, desenvolvemos um secador de fio para que garante a secagem antes da lubrificação, de modo a evitar empedramento do sabão, má lubrificação e consequentemente rupturas.

Aug 16, 2017

By L. M. Gochioco

The Seismic Interactive Interpretation Workstation (IIW) integrates various sets of geophysical and geological data to form a network of information which is stored in a database. Computer models are generated from known drillhole information and later correlated with the processed seismic data. Seismic color processing adds another dimension to the interpretation process. Complex trace attributes provide better definition of subtle features not easily observed from black and white sections. Utilizing the computer workstation, the explorationist gains valuable insight and conducts more intelligent interpretation of seismic data through a more comprehensive network of data analysis.

Jan 1, 1989

By C Sylvestre

Leaders have invested heavily in traditional safety management to improve safety performance over the years. This primarily involved: • fixing the environment (eliminating the hazard) • improving the system (more/less rules, procedures etc) • making safety more conscious (more/better interactions about the importance of safety). These approaches have helped improve safety performance significantly during the last 50 years and will continue to play a role in the future. Although these approaches may be part of an overall solution, they are not enough to prevent many incidents. Today, these three approaches are used more than before, and are used better than ever before. Yet, workplace fatalities in Australia have stagnated from 2013 to 2019, as have the number of incidents, even serious ones. In the USA, workplace fatalities have increased by 15 per cent in the same period.

May 5, 2022

By Kasimcan Koruk, Julian M. Ortiz

A geological model accounting for uncertainties possesses important advantages for resource estimation. Machine learning algorithms (MLAs) employed on multivariate geochemical datasets open up ways to new methodologies for such geological models with ease in comparison to traditional geostatistical methods. This article proposes a two-step MLA with an ensemble implementation to define geological domains and their uncertainties based on geochemical data. The proposed workflow is applied hierarchically on a dataset from a porphyry copper deposit to perform binary classification that can be attributed to alteration domains.

Mar 1, 2024

MAY 17-The last bit of verbal sod had hardly come to rest on the grave of the coal industry-which grave was being eagerly dug with typewriters and microphones by administration hangers-on and even an operator or two-when its leaders gathered for the 1950 Coal Convention of the AMC in Cincinnati on April 24. Surprisingly, mourning clothes were not being worn but the boys had on their diggers preparatory to digging their way out from under the muck. High costs created by wage and welfare demands, together with work stoppages, have caused markets to shrink, but even so, an optimistic air still prevailed as new techniques were disclosed at technical sessions. The administration, however, came in for its share of knocks.

Jan 6, 1950

By J. F. T. Agapito

Significant increases in extraction ratio on the order of six to eight percent, equivalent to as much as 142 t/m of panel advance, have occurred at the Big Island Mine during the last five years with the help of a practical rock mechanics program. This increase in resource recovery also has contributed to improvements in productivity. Both conventional and continuous machine mining have been used to mine two flat-laying trona beds at depths of 250 to 260 m in the Green River Formation in south-western Wyoming.

Jan 1, 1988

By Sven Petersen

In April 2010 three REMUS6000 series autonomous underwater vehicles (AUVs) have been used to simultaneously map large areas near the Mid-Atlantic Ridge (3°N) axis in water depths ranging from 1,000m to 4,000m. One vehicle was provided by the Leibniz-Institute for Marine Science, IFM-GEOMAR (Kiel, Germany) the other two were provided by the Waitt Institute for Discovery (La Jolla, USA) and managed by the Woods Hole Oceanographic Institute (USA). The REMUS6000 vehicles, manufactured by Hydroid Inc. (USA), are "cigar-shaped" vehicles (4m long and weighing approx. 900kg) and consist of a tapered forward section, a cylindrical midsection and a tapered tail section. An internal titanium strongback, which extends through much of the vehicle length, provides the structural integrity and acts as a mounting platform for syntactic foam, equipment housings, various sensors and release mechanisms. The AUVs can be used in various payload configurations such as multibeam bathymetry, electronic still camera, or subbottom profiler. For these missions the electronic still camera configurations was installed. An EDGETECH 2200M dual frequency (120/410 kHz) side scan sonar was used to map the seafloor, but other frequencies are readily available for more options in resolution and range. The 120 kHz side scan transmitter was used for most missions in order to map large areas (increased range) and to be able to fly at higher altitudes (between 70m and 90m) above the rough seabed encountered in this area. The maximum slant range was between 600m and 700m on both sides resulting in a swath width of up to 1.2 km. Line spacing ranged from nearly 1,000m in flat areas down to 400m in steep terrain. Side-scan mosaics were generated with a 1m resolution. Selected areas were targeted by the higher resolution 410 kHz transmitter as well as by bottom photographs flying as low as a few meters above the seabed. The vehicles navigated autonomously using a combination of inertial navigation (Kearfott T-24 or T-16 INS) and long baseline acoustic navigation by computing their range to two moored acoustic transponders. Working efficiently in this rough topography at speeds above 3 knots was only possible due to the obstacle avoidance capabilities of these AUVs.

Jan 1, 2011

By Timothy Batchler, Khaled Mohamed

Standing supports have been used in coal mines for decades to enhance roof support capability. Occasionally, standing supports are used to resist the lateral movement of spalled ribs. Researchers from the National Institute for Occupational Safety and Health (NIOSH) are conducting a testing program for standing supports to investigate the effect of lateral loading on their vertical loading capacities and the factors affecting their lateral loading capacities. The Mine Roof Simulator (MRS) was used to determine the response of steel props to vertical and horizontal loadings. Finite element models (FEMs) were developed and verified using the tested steel props. Prop models were used to study the effect of a range of roof and floor materials — gray shale, shale and claystone — on the critical buckling loads of the steel props.

Dec 1, 2022

By Hiroki Kumakura, Kotaro Seki, Takashi Nagai, Masahito Abe, Daiki Noguchi

A large amount of platinum group metals (PGM) are used in automobile catalyst. It is important to recover the metals from wasted catalyst. PGM in the catalyst are supported by ceramics for four-wheel vehicle or metals such as stainless steel for two-wheel ones. The recycling process of PGM from the metal-supported catalyst has not been developed, while the process for ceramic-supported catalyst was developed, such as Rose process. We designed a noble recycling process of PGM from metal-supported catalyst using complex oxides between PbO and PGM oxide. In this study, complex oxides, PbPt2O4, PbPdO2, PbRh2O4 and so on were synthesized at about 773–973 K. And the dissolution behavior of these compounds to hydrochloric acid was investigated. PbPt2O4 and PbPdO2 were dissolved to hydrochloric acid easily, but PbRh2O4 was not.

Mar 1, 2017

By H J. J Boshoff, A J. Karrasch

Mine planners frequently face the challenge of mitigating the impact of climatic events on mining operations, such as floods and droughts. Specific water management infrastructure can be implemented to meet operational requirements in response to these events. However, the effect of flood protection, for instance, may reduce the resilience of the site to drought. The probability and duration of unfavourable climate sequences significantly influences the net present value (NPV) of implementing specific water management infrastructure.Good life-of-mine planning will consider the incremental development of the project, and provide staged development plans. Water management infrastructure and the timing of implementation are facets of this process.CITATION:Boshoff, H J J and Karrasch, A J, 2016. A decision-making framework for water supply and flood protection options in net present value terms, in Proceedings Life-of-Mine 2016 Conference , pp 196–199 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016

By Steve Dillingham

A blast site incident has just occurred. Tensions are high, and, as the blaster, you’re in charge of the crisis at hand. Your mind is reeling, your thoughts frantic. The main areas of concern for you at the scene are to deal with immediate problems...aid the injured, take a head count, assess the damage, call emergency response, contact company headquarters, calm the neighbors, update your customer, and respond to the press on site. You feel as if all the bases have been covered...but, then again, have they? One of the biggest mistakes blasters and their companies can make is not including their Insurance carrier in the critical on-site accident procedures and emergency call list. Unfortunately, many companies believe that they are immune to the perils that can often, within a matter of minutes, create chaos that only happens to someone else.

Jan 1, 2002

By Sukumar Bandopadhyay

The Marine Minerals Technology Center (MMTC) was authorized by an act of the United States Congress in 1996. The act established several marine minerals research centers in the U.S., including one at the University of Alaska Fairbanks. The Alaska MMTC is funded through the Minerals Management Service of the Department of the Interior and concentrates its research in the Arctic seas region. Recent research projects at the MMTC include, among others, application of a geographic information system (GIS) to the gold placer deposits offshore Nome, Alaska, development of a marine gold placer reserve definition model using a neural network, and development of an expert system model for submarine tailings disposal (STD) planning and decision-making. Although geostatistics remains the most prevalent method used today for ore grade estimation, researchers have made numerous improvements over the years for accurately predicting grades of ore using other estimation techniques. One such technique, the neural network, has recently emerged as an alternative to geostatistics for grade estimation purposes. A neural network is a non-linear, model-free estimator that is well-suited for noisy and/or sparse data environments. Neural networks perform best with non-linear spatial data, contrary to the stationary assumption of ordinary Kriging techniques. In the marine placer ore reserve definition model, the neural network technique was used to estimate placer gold reserves offshore Nome. This study demonstrated the utility of neural network modeling over other traditional ore reserve estimation methods, especially for high cut-off grades. Some of the relevant issues of neural network modeling were also addressed in the study. In testing, the neural network produced results that were close to those from geostatistical techniques including Kriging, polygonal, and inverse distance methods.

Jan 1, 2005

By J. M. Mutmansky

The SIMAN (SIMulation ANalysis) computer language is a general-purpose, discrete-continuous simulation language for modeling a variety of multi-component systems. The language has been described by its author in a textbook (Pegden, 1985) and in a paper (Pegden, 1986) and is available in a mainframe version, a minicomputer version and a microcomputer version. The language was designed for and has been extensively used for modeling manufacturing systems but possesses many features that are advantageous in the modeling of mining materials handling systems. Consequently, the authors have applied the language to the simulation of an open pit shovel/truck operation to test its usefulness for simulating mine materials handling systems. This paper presents a short background on simulation languages, the capabilities and modeling framework of the SIMAN language, a description of the application of SIMAN to a shovel-track operation and some results and conclusions on the use of the language for mining materials handling systems.

Jan 1, 1988

By William Gleason

With its 2011 acquisition of rival equipment company Bucyrus International, Caterpillar added underground mining and large shovels to its line of products and further solidified its standing as the leading mining equipment manufacturer in the world with solutions for every aspect of mining. When Caterpillar spent $8.8 billion to acquire Bucyrus, the global mining business was flourishing, as mining companies around the world worked to keep up with demands for nearly every commodity. Flash forward to 2013, and the global mining landscape looks very different. Lower demand for raw material from China and India and falling commodity prices have forced most mining companies to pull back on their production. The reductions from the mining industry have hit equipment makers like Caterpillar and Komatsu hard. In October, Caterpillar reported that its quarterly earnings had fallen 44 percent. The changing conditions have also changed the narrative from Caterpillar and other equipment makers to customers from offering solutions to move the most tons per hour, to now offering solutions for the lowest cost per ton. In September, Caterpillar hosted some of its mining customers and the trade press at its Tinaja Hills Demonstration and Learning Center near Tucson, AZ to talk about its range of products, from its MineStar System designed to help increase efficiency through better equipment management and planning, all the way up to the massive Cat 7495 and 7495HF electric rope shovel lines acquired through the Bucyrus takeover

Dec 1, 2013

By Unkown

The Province-wide road ban on movement of heavy loads has had the effect of curtailing or stopping development in several areas. In the Leduc area, the discovery well has been restricted in flow to only a fraction of normal due to limited storage space, but drilling at Imperial Leduc Nos. 2, 3, and 4 has been continued for the past few weeks. The No. 2 well is within 100 feet of the producing horizon and should be completed within the next few days. According to reports, it has been logging slightly lower, structurally, than the discovery well, but, regardless of the outcome, it has been an important test to determine westerly cross-section of the Leduc structure. No official reports have been made available of any tests made during the drilling of the well, but it is understood that promising oil and gas shows have been indicated in higher formations. Actual drilling operations have not been commenced by any of the other companies holding leases in the immediate area but it is expected that, when road bans are removed and equipment is assured, several wells will be commenced. Announcement has been made that Imperial Oil, Limited, will drill a well near Battle lake, about thirty-five miles southwest of the Leduc field. Location of the well has been made following an extensive seismograph survey of the area, with total depth of the test well expected to be in the 8,000- to 8,500-foot range. Drilling will be done with the heavy-duty rig last used at the De Winton test. Imperial Oil have abandoned hope of oil production in the Provost area after drilling nine wells, but will retain their interest in the gas field that has been developed. Of the wells drilled, four indicated gas flows ranging from 1,060 to 13,200 M.c.f. per day.

Jan 1, 1947

Employing gravity recovery for coarsely liberated gold and sulfide ores has potential to lead to a signifi cant reduction in the energy required for comminution and ultimately can have a significant impact on gold processing. Most of the recognised metallurgical tools at our disposal currently have been designed around recovery of relatively finely ground minerals. In order to change the paradigm of fine grind for liberation, a new set of tools need to be recognised that are capable of separations in the coarser size fractions. Some of these tools already exist and some need to be developed but the key is the way in which the fl ow sheets are arranged. A very strong understanding is required in the existing tools and their capabilities before these new flow sheets can be optimised. Only when we understand the existing gaps in technology can we start to fill these positions with new candidates. Many ores when crushed liberate their gold bearing minerals at coarser sizes than current practice would suggest (Figure 1). In order to characterise this response in ores it is necessary to utilise some new techniques in the lab such as gravity separation and ore sorting at the sizes greater than 15 mm followed by gravity recovery on fractions from 15 mm down to 150 ¦m. The most difficult range has been the mid-sized fraction from 4.0 mm down to around 150 ¦m. This is the size range in which many ores show economic liberation starting to occur and coincidentally this is the range in which many commonly used metallurgical processes reach their operational limits due to physical constraints. Examples of these processes are flotation, hydrocyclones and whole ore leach in agitated tanks which are currently the mainstays of the processing fraternity. This is an ABSTRACT ONLY. No paper was prepared for this presentation.

Aug 1, 2010

Relatively lower recoveries (60%) of coarse phosphate (-16 +35 mesh) particles are attributed to the difficulty in transportation of coarse particles from the pulp to the froth column and rapid drainage of these particles from the froth column to the pulp. Increasing the hydrophobicity of coarse particles by higher, more efficient coating of the collector and using larger froth volumes have been suggested to overcome these problems. In this study, the role of emulsification of the fatty acid-fuel oil collector on the flotation recovery of coarse particles was examined. It was determined that emulsification can not only increase the coarse particle recovery, but do so at higher fractions of fuel oil in the collector, thereby reducing the reagent cost as well.

Jan 1, 1989

By R J. Higgins, M Edraki

What is the meaning of the Life of a Mine (LOM) if that mine results in a requirement for water treatment in perpetuity? ‘In perpetuity’ is of course a duration with no relationship to a Life-of-Mine or what might rightly be regarded by external stakeholders as a fair and reasonable post-mine recovery period. It exceeds the life span of investors, mine managers and governments, indeed even of capital markets as we know them, and of corporate and individual memories.In mine and mine closure planning, decisions are usually based at least to a significant extent on traditional economic analysis underlain by discounted cash flows (DCF). For investments in income-producing facilities, such as mining development and equipment, and ore-processing plant and equipment, this analysis reflects commercial reality and allows for comparison of competing investments. However, for environmental and social infrastructure, the same analysis using the same input parameters, especially the discount rate applied to cash flows, can lead to a bias against the adoption of best practices for non-investor stakeholders. CITATION:Higgins, R J and Edraki, M, 2018. Water treatment in perpetuity – or not?, in Proceedings Life-of-Mine 2018, pp 131–132 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 25, 2018

A coal mine located in southern West Virginia recently set a world record for daily low-seam coal production using a Cat automated longwall plow system. In a 24-hour period on April 10 and 11, 2014, the Pinnacle Mine longwall produced 32,411 t (35,724 st) from the Virginia Pocahontas No. 3 Seam, in a seam height of just 1.42 m (56 in.) along the 298-m (980-ft) longwall face. The Pinnacle Mine, located near the town of Pineville and owned by Cliffs Natural Resources Inc., an international mining and resource company, operates a Cat Gleithobel GH1600 Longwall Plow System. A previous record was set by this system at Pinnacle in August, 2012 when 29,423 t (32,430 st) were mined in a 24-hour period. The record was set by the same system, mining its second panel after a comprehensive rebuild was performed by Carter Machinery, the Cat Dealer in that area. The rebuild encompassed a complete rebuild of the headgate and tailgate armored face conveyor (AFC) drive, the headgate and tailgate special AFC pans, the stageloader drives and return end, the complete crusher and all gearboxes for the plow, AFC and stageloader. Carter acquired the rights to sales and aftermarket support associated with the former Bucyrus mining products, both surface and underground, in 2013. ?Supporting and rebuilding a longwall plow system was a new experience for the Carter service team,? said Chris Curfman, president of Caterpillar Global Mining Sales and Support Division. ?However, given the record production results attained by the rebuilt system at Pinnacle, it?s obvious that they are up to the challenge of supporting the underground product lines at the same high standards and quality level that they have been delivering for many years on the traditional Cat surface mining products.? Tom Bluth, president of Caterpillar Global Mining Products Division, said, ?Caterpillar congratulates the Pinnacle team for this great achievement. Without their efforts and dedication this record would not have been possible. To safely deliver that kind of output from such a thin seam is remarkable. We have been privileged to work alongside their team to demonstrate the capabilities of Cat longwall mining technology. ?

By J. Scarbrough, J. Barrett

Vector Induced Polarization arrays aim to provide unbiased and minimally low spatial sampling of artificially generated electric fields to efficiently investigate the Induced Polarization and Resistivity variations in the subsurface, generally of use in the exploration of disseminated sulphide systems beneath large covered areas.

May 1, 2008