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Caterpillar unveiled a new dozer, the new Cat D10T2 dozer, that builds on the success the company has had with its D10T model. The newest version of the dozer includes refinements to its power train, automated controls and structures. The result, the company said, is high productivity with superior fuel efficiency, reliable operation with long-lived structures, as well as enhanced access for service technicians and operators. The D10T2 uses the latest load-sensing hydraulics technology combined with Cat advanced engine controls to maximize the amount of material moved for every drop of fuel burned. Improved filtration protects the fuel system, hydraulic system and power train oil system to help ensure high reliability and minimal machine downtime. Refined large structures, such as redesigned track roller frames, deliver longer service before rebuilds. Improved access and egress features enhance safety and productivity of technicians and operators, and optional powered access systems and platforms enable configuring the D10T2 for the site. Caterpillar offers the D10T2 with two variations of the Cat C27 engine with ACERT Technology. One version is U.S. Environmental Protection Agency (EPA) Tier 4 Final certified, and the other is capable of achieving emission levels equivalent to EPA Tier 2 standards. Both engine configurations produce net power of 447 kW (600 hp) in forward gears and 538 kW (722 hp) in reverse gears. The engine controller automatically adjusts power output based on the direction of travel. With the new system, the D10T2 has about 20 percent more power in reverse compared to its predecessor model. The result is faster cycle times and greater productivity in certain applications. The D10T2 is suited for a variety of applications including mining, heavy construction and bulk materials handling.

Mar 1, 2014

By Boleslav Taraba, Antonín Taufer

Thermovision monitoring of surface temperature has been examined for the purpose of detection of spontaneous combustion of early stage. Measurements were carried out in bituminous and subbituminous coal mines. It was found that surface temperature heterogenities can be considered as common phenomenon in mine openings. However, the most of the observed temperature heterogenities were not connected with coal spontaneous combustion of early stage. These, so called [non-spontaneous combustion] temperature heterogenities in surface of mine openings were found to be caused by: l. Different conditions of heat transfer between opening surface and air stream; 2. Low temperature (natural) oxidation of coal; 3. Dissipated heat loses of working machine. Sites of early stage spontaneous combustion of coal were characterized by: 1. More significant, local rise in surface temperature comparing with low temperature coal oxidation; 2. Evolution of carbon monoxide with local concentration near the surface of such site more than about 15 ppm (bituminous coals) or 30 ppm (subbituminous coals). INTRODUCTION Mine fires are a serious hazard to life and result in a considerable loss of coal reserves. Thus, great attention is paid to investigation of new methods enabling already early detection of self-heating of coal. The earlier a fire is observed, the easier would it be to deal with. Detection methods used in coal mines are mainly based on: 1. [Mine air analysis]. Changes in composition of mine air are examined. Products of spontaneous heating of coal, not being present in mine air under normal conditions, are considered as indicators of anomalous behaviour of coal (carbon monoxide, unsaturated hydrocarbons) (Mackenzie-Wood and Strang, 1990). 2. [Temperature measurements]. Sites of higher temperature level comparing surroundings are looking for underground using various direct or indirect methods of temperature measurements. This paper summarizes experience from thermovision monitoring, as one of the latest indirect temperature measurement technique, used for the purpose of early detection of self-heating of coal in mine openings. INFRARED THERMOVISION Infrared thermovision device of AGEMA Infrared systems AB (Sweden) was used for the in situ measurements. The constant value of emissivity factor, 0.95, was pre-set as the most probable level of emissivities of coal and rocks in mine conditions.

Jan 1, 1993

By D. Weston

During recent years there has been a great deal of confusion in the North American mining industry with the introduction of new comminution terminology and claims (without substantiative evidence), for various types of equipment in this field. The authors will attempt to clarify the terminology used, and where possible, give illustrations of plant practice with actual operational and pilot plant data. This is considered necessary in order to obtain a clear picture of the comparison of such equipment to the revolutionary change that the Aerofall Mill has brought to the mining industry.

Jan 1, 1964

By Josh B. Taggart

Some twenty to twenty-five years ago we saw the beginning of mechanization in our coal mines, It has now progressed to the point Chat as instruments of production the pick and shovel are things of the past, They had to give way to better and more efficient methods--so mechanization, followed by and combined with automation, has become common-place in our mines. Our coal could not keep its competitive position without this progress Without it our industry could not look to the future with any degress of confidence. Today we lock back and see cases of regained and salvaged markets. We see better coal products being produced at decreasing costs. We see better utilization of manpower and a stronger, more confident industry, Our hats arc off to those mining men, equipment manufacturers, labor leaders, and others who had the foresight to work toward these ends and the ability to bring them about.

Jan 1, 1962

By Henry H. Roos

The productivity of the underground driller has increased 500-600% during the past 20 years. This increase is not due so much to improved percussion drills as it is to improved drill support equipment and modernization of mining methods, Efforts to mechanize drilling in mining operations were made as early as the late 1800's; and, patents on rock drill manipulating machinery date back to 1906. However, the great rush to mechanization began in the 1950's when the development of trackless mining methods gave mining engineers and equipment designers their first opportunity to create improved operating conditions for the equipment and to match the equipment with these conditions. Accordingly, this paper will summarize the developments of the past 20 years and will attempt a forecast of developments that can be expected during the next few years.

Jan 1, 1970

By Gary Almeraris, Vincent Jr Tirolo

Traditionally, “Means and Methods” were the sole responsibility of Contractors. However, because of a number of litigious projects in the 1970s, Owners and their Engineers began including Suggested Methods of Construction (SMC) in Contract Drawings. By the late 1990s these SMCs were becoming baseline “Means and Methods” with Contractor recommended changes often considered as Value Engineering proposals. By 2004, the word “Suggested” was sometimes changed to “Prescriptive.” Owners are also purchasing TBMs and other mining equipment for Contractors prior to bid. Is limiting the contracting community’s innovation in developing their own “Means and Methods” and selecting their own equipment in the best interests of the Owner? Does it reduce the Owner’s, Engineer’s or the Contractor’s risk? Are claims reduced and finally what is the impact on the bid? A questionnaire was sent to more than fifty senior engineering field and management personnel representing more than 30 heavy construction companies to ask their opinion on these questions.

Jan 1, 2005

By S. Kim Juniper

"This presentation aims to serve as a primer on conservation, research and regulatory organizations interested in the environmental impact of deep-sea mining. It will also consider a recent, early-stage proposal for an experimental SMS mining operation aimed at increasing our understanding of mining impacts and ecosystem recovery.Over the past 5 years, as deep-sea mining has been moving closer to reality, it has attracted growing attention from deep-sea biologists, conservation groups and operators of deep-sea research vehicles and observing systems. Several new international research organizations have emerged that have a direct interest in deep-sea biodiversity conservation, and the environmental impact of ocean mining. These include INDEEP, which evolved from the 10-year Census of Marine Life program, the Deep Ocean Stewardship Initiative that has recently hosted several high profile international meetings, and the VentBase forum of academics, industry and regulators that aims to develop environmental best practices and informational documents for all stakeholders involved in Seafloor Massive Sulphide (SMS) mining. InterRidge, currently hosted by China, represents a decades old partnership of deep-sea biologists and economic geologists who discovered the more than 100 known hydrothermal vent fields and SMS deposits on midocean ridges and in other settings of seafloor volcanism. In 2012 InterRidge formed an industry liaison group to examine how the mid-ocean ridge researcher community could contribute to the development of environmentally responsible practices for the exploration and exploitation of SMS deposits. While initial meetings with industry were promising, InterRidge members are currently debating the relative merits of sharing exploration know-how and understanding of vent ecosystems with industry, against the need to maintain their independence as stewards of deep-sea ecosystems."

Sep 1, 2014

By P. T. Bissert, L. Yan, J. R. Srednicki, J. A. Yonkey

"Refuge alternatives (RAs) are required in underground coal mines to support life post-disaster. RAs are mandated by MSHA to maintain an apparent temperature (AT) at or below 95°F (35°C) while providing a safe and livable shelter for a minimum of 96 hours. Because strata composition and mine temperatures will affect the final AT within an occupied RA, NIOSH researchers have collaborated with five underground coal mines across the US to characterize the effects of geographic location and seasonal temperature fluctuations on mine air temperature, relative humidity, and mine strata temperatures. The data collected indicates that some mines will experience greater temperature fluctuations than others, based on geographic location. The mine which demonstrated the greatest temperature differential over the course of the year resulted in a mine air temperature that ranged from 53.4°F (11.9°C) to 84.2°F (29.0°C) and a rib surface temperature that ranged from 55.4°F (13.0°C) to 82.8°F (28.2°C). This data suggests that the location and seasonal peak temperature can significantly affect the mine strata temperature, which could lead to a fully occupied RA exceeding the 95°F (35°C) AT limit over the course of 96 hours. The data reported in this paper could be used to examine the heat buildup inside an RA for actual mine conditions. Thermal simulations could be implemented to evaluate maximum occupancy ratings based on actual mine temperatures and strata compositions. INTRODUCTION In the event of a mine disaster, miners’ primary focus is to escape. Should their attempt be futile, they can enter a refuge alternative (RA) to await rescue. In 2008, the Mine Safety and Health Administration (MSHA) mandated that underground coal mines implement RAs within 1,000 ft (304.8 m) of the working face and spaced within one-hour travel distances in outby areas where persons work such that persons in outby areas are never more than than a 30-minute travel distance from an RA or safe exit. These RAs are required to provide a safe and habitable shelter for a minimum of 96 hours and to prevent the apparent temperature (AT) from exceeding 95°F (35°C) [1]. There is concern throughout the industry that in some cases the internal ambient of occupied RAs may exceed the 95°F (35°C) AT limit due to the potentially hot mine atmosphere as well as the metabolic heat generated by RA occupants and the carbon dioxide scrubbing system. The National Institute for Occupational Safety and Health (NIOSH) has conducted tests in its Safety Research Coal Mine (SRCM) and its Experimental Mine (EM) to investigate heat buildup in RAs. It was found that the number of occupants in an RA may need to be reduced based on the ambient mine temperature, which varies from mine to mine [2]. Further testing and analyses were completed to evaluate the mechanisms (conduction, convection, radiation) by which heat is transferred from an RA to the mine surroundings. Additionally, the effects of varying mine strata compositions on the heat buildup inside an RA were studied [3]. The mine strata temperatures will increase due to heat transfer from within an RA. Depending on the mine strata composition, some mines may be more thermally conductive than others. For example, sandstone is much more conductive than shale or coal (i.e. it disippates heat at a quicker rate). All things being equal, the air temperature inside of an RA after 96 hours will be higher for a mine with strata that has low thermal conductivity compared to a mine with high thermal conductivity."

Jan 1, 2017

By David R. Delling

Tenneco is a large, diversified, energy-based company which has grown rapidly during its forty year life. We're the youngest corporation among Fortune's top 20 companies. Tenneco Minerals Company is the division of the Corporation responsible for nonfuel minerals exploration, development and operations. Tenneco Minerals Company is headquartered in Lakewood, Colorado. Exploration offices are in Colorado, Nevada, Alaska, and Perth, Australia. We currently operate two gold mines in Nevada and a large underground trona mine and soda ash processing plant in Wyoming. The latter has a capacity of 907 000 tonnes per year of soda ash and is the subject of my presentation today.

Jan 1, 1984

By H. G. Stephenson

Canada and the United states are both developed countries with economies which are extremely dependant on oil. Canada exports 37% of its production (to the United states) and imports 35% of its consumption (mainly into Eastern Canada), making the country self-sufficient in oil. Canada is attempting to increase its oil production so as to simultaneously reduce its dependence on foreign oil while producing more oil for export. The United states -imports no less than 50% of its total consumption of 17 million barrels/day. Canada's exports to the United states form only 7% of the United States total imports. The United States would clearly prefer to achieve self-sufficiency in oil. Consequently both countries are dependent on foreign oil. The united States is however in the sensitive situation of depending, for its imports, on countries which are susceptible to destabilizing political events. It is the author's hypothesis that recent developments in underground oil recovery from the Athabasca oil Sands of Alberta may well, for both countries, form part of the solution to these problems.

Jan 1, 1991

By G. R. Doubek

Dual Tube Reverse Circulation (DTRC) drilling has been extensively used for collecting groundwater information for the dewatering program at Amax Gold Inc. Sleeper Mine. This paper presents a discuss ion of the types of data which can be collected from DTRC drilling, as well as the effect submergence has on the data. A simple low-cost method of injection testing has been developed using DTRC equipment, allowing quantitative data to be obtained from exploration or test holes. Potential yields can be determined for each drill location, allowing siting and design of production wells to be optimized.

Jan 1, 1992

By R. R. Bhappu

The metallurgical processing industry is in the midst of a hydrometallurgical revolution with mining companies looking for low cost, energy efficient and environmentally friendly technologies for processing sulfide ores and concentrates. The Intec Copper Process is one of the most advanced of these technologies and has the potential to greatly change the way copper concentrates are treated in the future. Specifically, the Intec process has the ability to be built on a small scale and at mine sites while being much more economic than conventional smelting. Intec Copper has constructed a I tonne of copper per day demonstration plant in Sydney, Australia designed to verify metallurgical and operational performance. This paper will describe the process in more detail and provide preliminary results of the process based on the plant's performance. It will also compare the Intec Copper Process with a few of the competing technologies and evaluate the relative economic merits of Intec.

Jan 1, 1999

By Carleton K. Smith

Due to special job or client requirements, there will always be some variation in the philosophy of organizing and controlling construction under a project management contract. In typical cases, however, some standard procedures apply. Controls on a construction project are best described only in general terms. They should apply to the total job and can be most effective only when all pieces of the job organization fit together to support a control system for the entire project. Controls are more than a system of reports, schedules, and tabulations-they are the result of an integrated organization dedicated to getting a job done on time and within budget. One of the most important aspects of project control is the construction organization. It must include the right people, facilities, and site equipment, as well as the authority to do what's necessary to accomplish the work. This should be set up to function with as little involvement from off-site or the home office as possible. However, the jobsite construction group must work within established policies and guidelines and is subject to continuous off-site or home office monitoring. In other words, the job-site leaders need to have a clear definition of their responsibility, their authority, and the necessary people and equipment to make things happen. With that philosophy in mind, this is how Bechtel sets up a new job to be

Jan 10, 1980

By Ralf Plinninger, Pafos Busch, Richard Gradnik

This paper presents the details of the Bad Bergzabern tunnel project. This tunnel is the main part of the B427 federal road bypass, intended to improve the regional traffic infrastructure and to reduce the traffic load in the historic city centre of the health resort Bad Bergzabern. Located in the south-western part of Germany, the project area is situated at the eastern margin of the so-called Palatinate Forest, a low mountain region of mainly triassic sediments with a complex and variable geological history. The German federal government, represented by the office of mobility of Rhineland- Palatinate, awarded the contract to BeMo Tunnelling, a specialized Tunnelling company with a long history of innovation and success in NATM tunnelling. The contract includes the construction of two separate tubes with a length of approximately 1,44 km (0.9 mi)—the road (main) tunnel with a cross section of 101 m2 (1,090 sq ft) and a parallel rescue tunnel with a cross section of ca. 23 m2 (250 sq ft.) Both are connected by six cross passages. Tunnels and cross passages are excavated according to the principles of the New Austrian Tunnelling Method (NATM). Due to BeMo Tunnelling’s technical expertise and capabilities, the project team was able to engineer a speed-up concept that saves money and time for the construction team and client. This paper presents the innovative approach BeMo Tunnelling made to optimize the execution of the tunnelling works and the challenges the project team is facing with regard to a complicated geological situation, countermeasures against an increasing effect of climate change and volatile prices for construction materials.

Jun 13, 2023

By T. Payne

Underground heat issues are mainly focused on the detrimental effects to a workers health. However, working in hot, humid conditions has other negative effects. Studies have shown that safety, productivity, workforce morale and operating cost are also worsened in these conditions. The human body has several mechanisms for rejecting heat and remaining cool. However, once the air temperature exceeds about 34°C, the only effective mechanism is by evaporation of sweat from the skin. This is assisted by acclimatisation which is the human body?s enhanced ability to combat extended exposure to heat. The body has to remain well hydrated when working in heat as even small degrees of dehydration cause significant decreases in the ability to work in heat. There are two ways in which heat load can be reduced: Through use of refrigeration/vent/cooling to reduce thermal stress on workers; Reduce the contribution that heat sources have to underground heat load (e.g. reduce idle time, fleet size, etc). Some of the sources of underground heat have the potential to be more manageable than others. Geothermal heat and heat from autocompression will be found in all mining situations in varying degrees depending on geothermal gradient and surface temperature, however, the use of equipment and blasting may be streamlined to reduce the underground heat load. It is through a combination of the available options that most mines will successfully control their heat related problems. Mt Isa, which has been a focus for heat related study in Australia, has successfully implemented protocols for working in heat. Through combining these with the installation of a surface bulk air cooling plant, Mt Isa has consistently reduced the incidence of heat illness. This is likely to be the most cost effective method of reducing heat load for deep mines in Australia. Shallower mines which may only occasionally encounter hot conditions should consider more portable cooling options. This study will review the heat issues in underground Australian metalliferous mines.

Jan 1, 2009

By Zhiguo Chang, QINGXIANG CAI, Ebelia Manda, IZHAR MITHAL JISKANI, XIANG LU, Wei Zhou, Saleem Raza Chalgri

The concept of mine safety is highlighted in the literature of sustainable mining but not extensively discussed. This study analyzes various aspects of underground and surface mine safety and emphasizes its importance in the context of sustainable mining. More specifically, this research attempts to find the relationship between mine hazards and demographic characteristics, examine and compare the perceptual difference among miners, and determine the impact of mine hazards on workplace safety and safety climate. Descriptive analysis, chi-square test, independent samples t test, and linear regression modeling were conducted to achieve study objectives. Results confirmed that mine hazards were significantly associated with age and experience. Miners perceived lower levels of management safety practices, followed by supervisor safety, coworker safety, and job safety. The analysis showed that underground miners reported lower safety scores than surface miners. There was a statistically significant difference between miners’ perception of safety climate (p < 0.05). The results showed that the higher prevalence of mine hazards predicts poor workplace safety and a low safety climate. The regression models revealed that mine hazards have a significant effect on workplace safety (p < 0.05) and safety climate (p < 0.05). In conclusion, the distinctive model of mine safety presented here contributes to the monitoring and design of comprehensive safety interventions and helps to better understand how certain factors interact on multiple levels to influence the overall safety of the industry. In this study, some suggestions are put forward to provide directions to develop a sustainable mine safety system.

Mar 27, 2020

By C. H. Stephenson, Z. White

This paper presents the design approach case study for incorporating a Technogrid® conveyance End-of-wind arresting system within the new South32 Hermosa headframe. Focus is placed on energy absorption requirements, structural integration, and mounting details tailored to the geometry and operational constraints of the headframe. Key considerations include arresting forces, load path continuity, and connection design to ensure reliability and maintainability. The paper also discusses coordination with other headframe systems and the iterative design process used to meet safety standards and client objectives.

Feb 22, 2026

By K. J. Shoop

This study investigates the use of a horizontally-baffled column (7.6 cm inside diameter by 344.2 cm high) to reduce the ash content of a high ash bituminous coal. Tests were carried out to determine how the baffled column responded to changes in feed rate, reagent dosage, and feed quality, and to compare its performance with a conventional column installation in an operating plant. In this paper, the results of this investigation will be reviewed and discussed.

Jan 1, 1997

By Philip Lindstrom

Retreat mining, using yielding steel friction props, over a seven-year period has been successful at a uranium mine operated by Hecla Mining Company in southeast Utah. The support system allow good roof control, maximum profit, complete extraction, and good ventilation. Unusual subsidence observations were made in that some of the surface was raised rather than lowered, Longwall mining, commonly practiced in European coal mines, has a potential of broader application because of mechanization possibilities and better roof control and ventilation at greater depths.

Jan 1, 1964

By W. R. Reed, S. Klima, J. Driscoll, T. W. Beck

"Tests were conducted to determine properties of four foam agents for their potential use in longwall mining dust control. Foam has been tried in underground mining in the past for dust control and is currently being reconsidered for use in underground coal longwall operations in order to help those operations comply with the Mine Safety and Health Administration’s lower coal mine respirable dust standard of 1.5 mg/m3. Foams were generated using two different methods. One method used compressed air and water pressure to generate foam, while the other method used low-pressure air generated by a blower and water pressure using a foam generator developed by the U.S. National Institute for Occupational Safety and Health. Foam property tests, consisting of a foam expansion ratio test and a water drainage test, were conducted to classify foams. Compressed-air-generated foams tended to have low expansion ratios, from 10 to 19, with high water drainage. Blower-air-generated foams had higher foam expansion ratios, from 30 to 60, with lower water drainage. Foams produced within these ranges of expansion ratios are stable and potentially suitable for dust control. The test results eliminated two foam agents for future testing because they had poor expansion ratios. The remaining two foam agents seem to have properties adequate for dust control. These material property tests can be used to classify foams for their potential use in longwall mining dust control. IntroductionAbout one-half of U.S. underground coal is produced by longwall mining, which allows for mining high volumes of coal but generates significant amounts of coal mine dust. This can lead to overexposures for longwall miners and possibly occupational respiratory diseases, including black lung and silicosis, which have no cure and can be disabling or fatal. The only method to avoid these occupational illnesses is through elimination of exposure to respirable coal mine dust and crystalline silica (quartz). The current occupational exposure limit for respirable coal mine dust is 1.5 mg/m3 during each shift that a miner is exposed in the active workings of the mine or in mine facilities (Mine Safety and Health Administration (MSHA), 2015a). When respirable quartz is present, the mine must maintain average concentrations at or below 0.1 mg/m3. If the mine exceeds the 0.1 mg/m3 respirable quartz dust concentration, then the applicable respirable dust standard is reduced, calculated as 10 divided by the percent quartz present (MSHA, 2015b)."

Jan 1, 2018