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By R. R. Hornor, Geo. M. Hunt

The purpose of this paper is to point out some of the benefits and economies to be derived by the better selection , preparation, storage , preservation and utilization of mine timber , and to give some specific information on certain wood preservatives and processes suitable for mine timber preservation . The paper is based largely upon data obtained by actual experimentation and service tests conducted by the U. S. Forest Products Laboratory , Madison, Wisconsin, on wood preservation , covering a period of many years , and upon a field survey during the past summer by one of the mining engineers of the U. S. Bureau of Mines of some of the principal mining districts of Michigan , South Dakota , Montana , and Idaho , in which he made a general ' study of mine timber in metal mines , particular attention "being given to timber decay ; the conditions under which it takes place most actively ; the measures , if any , that are being used to combat it; and, finally, the advantages that might be anticipated in the use of chemically treated timber to prevent decay and thus prolong its life .

Feb 1, 1922

By J. Eric Nylund

"Intensive mechanization and automation in the LKAB, Kiruna Mine in Sweden have resulted in substantial rise in productivity and decrease in production cost. Capital investment in a modern mine today averages a considerable amount per miner and costs increase with requirements for more efficient methods and equipment. Equipment reliability becomes more and more important. Equipment maintenance requirements are directly proportional to equipment reliability and grade of availability. Weaknesses in the equipment result in unnecessary costs with regard to maintenance which can add up considerably per year, but of more importance are the costs caused by equipment breakdown. These breakdowns disturb or interrupt the production and often cause damage to other parts of the system. This paper discusses the important parameters involved in mine car wheel wear and the design principles of wheels, axle suspension and track.IntroductionTrains operating in an underground mine do not follow the same standard of performance as trains operating on surface railways. The differences in speed, curve radius and environment require different methods of calculation for underground train systems, and when judging the parameters involved one must keep in mind these differences at all times.While surface railway technology was given all possible attention over the last century no one was seriously looking into underground rail haulage in the sense of rail vehicles performance on the track until LKAB in 1975 started to question the methods of calculations used. Even though LKAB by then attained mine car maintenance cost that was 1/6 to 1/10 of other mining companies they were not pleased with the situation. The objective for the ensuing engineering work was to derive the reasons for wear and breakdowns. Once those reasons were established, the design of a completely new generation of mine cars could start. The result of these efforts were beyond all expectations. The maintenance cost on mine cars had been reduced to 1/15 of prior car generation which already had comparatively low cost.The most significant cost savings were made on wheel maintenance, which earlier represented 50% to 55% of car maintenance. Wheel life was increased from an average of 3 to 30 years or more.The LKAB theories around wheel wear are described in the following report."

Jan 1, 1987

By S. A. G. Poppen, J. Konopka

"Petro-Canada's project investigative and experimental underground work in the Galt coal seam at Kipp, Alberta included the construction of an emergency egress and ventilation raise from surface.The Galt coal seam is 206 m below the surface and covered by 8 m of shale, sandstone and clay beds of the Oldman Formation, 128 m of shale, bentonite beds and sandstone of the Bearpaw Formation, and 70 m of glacial till and basal gravel. Free water was encountered from sand lenses in the glacial till and the basal gravel.Excavation for the ventilation raise was a nominal 2 m diameter and it was lined with a welded, continuous, steel liner of 1.2 m 1.D.Excavation in the glacial till was carried out with a surface bucket drill rig combined with hand mining. Ground support in the glacial till consisted of liner plates and backfill grout. The Bearpaw and Oldman formations were excavated by employing standard raise boring techniques. The individual liner sections of the continuous steel liner were assembled on surface and the entire liner column was lowered into the raise by employing hydraulic lift climbers. The liner column was back-filled with concrete.IntroductionThe Lethbridge Coal Field comprises an area of approximately 1 165 square km in the vicinity of Lethbridge in southern Alberta. Pacific Petroleums Ltd. proposed in a Preliminary Disclosure in January 1979 ""to open an experimental mine prior to development of a producing underground mine with an initial rate of 540,000 tonnes per year"". A 2 900-hectare group of leases in the Kipp-Coalhurst area was selected as the primary target for the Kipp experimental mine. The scope of work for the experimental mine included the construction of an access shaft with production capabilities, the construction of a ventilation and emergency exit raise, drive-ages in coal to yield a bulk sample, gathering of geotechnical information and the testing of experimental mining methods."

Jan 1, 1983

By Oliver Bowles

ASBESTOS is a name applied to a group of naturally fibrous minerals. As indicated in a later section devoted to a detailed discussion of the early history of asbestos, the tern may be defined as a. fibrous form of serpentine or amphibole. It does not include fibrous forms of other minerals, such as wollastonite, nemalite (fibrous brucite), or the fibrous forms of calcite or gypsum. A material that has the characteristics of silk or cotton and at the same time will not burn is unique. Because it combines these qualities with other advantageous properties, asbestos has specialized uses for which no substitutes are yet available. Asbestos furnishes a major raw material for a great variety of essential products and their manufacture constitutes a vast industry. The United States leads all countries in the manufacture of asbestos products. The value of such commodities manufactured in 1952 exceeded $332 million. They are not only of vast importance to budding construction and industry but axe absolutely, essential to certain important fields of use, for example, steam packings and friction materials, such as brake-band linings on automobiles.

Jan 1, 1955

By Edwin B. Cook

Studies of flame and combustion phenomena at the Bureau of Mines have been facilitated by computer evaluation of the thermodynamic properties of gases formed by constant-pressure burning.4 5 This report is the sixth of a series6-10 presenting results of such calculations; it deals also with constant-volume deuterium-air flames.

Jan 1, 1961

By F. H. Deily, D. S. Rowley, R. J. Howe

By Zabetakis M. G.

This Bureau of Mines report presents a brief summary of the explosion trends in United States coal mines for the past 160 years. These trends show that in spite of the overall improvements in mine safety, the number of fatalities from ignitions of methane has actually increased in recent years. Suggestions are made of procedures that can be utilized to reverse this trend.

Jan 1, 1973

There is no doubt that the mining sector is considered to be the backbone of many countries. Furthermore, it has played an important role in the prosperity of nations, whether developed or developing. Saudi Arabia is one of these countries that has a large variety of metallic and non-metallic mineral resources that range in size and value occurrences of limited potential to deposits large enough to sustain profitable exploitation. Therefore, the Saudi government needs to reinforce the capacity of the sectoral institutions to better regulate and promote the sustainable development of the sector. The ability to overcome the administrative and legal complications that constrain private sector participation in the minerals sector, through new mining code which will streamline the procedures for obtaining licenses and will add more predictability and transparency to the application process, are proposed for increasing the sustainable development. This paper will outline how the Saudi government is tackling the major challenges that face the minerals industry. This paper provides the background to the Saudi Arabian mineral sector and its industrial base. Finally, the paper identifies the problems and constraints that face the minerals sector in Saudi Arabia and provides an assessment of the effects of government policies and planning efforts in the minerals sector, particularly during the period of the development plans which started in 1970.

Jan 1, 2009

By The Staff

BEFORE going into detail on the subject to be presented, a brief outline of the Company's earl y history would not be out of place. Prospecting and mining on a small scale was started in 1876 on the site of the present open pit at Thetford Mines. The property was purchased from the Crown in 1878 and Johnson's Company was incorporated in 1885. It is owned and operated today by descendants of the original shareholders. Many employees, through their fathers and grandfathers, have service records dating back three generations. The principal asbestos deposit at Thetford Mines is pear-shaped, with surface dimensions of about 2,200 feet in length by 1,300 feet in maximum . width. Its long axis strikes northeast and the dip is nearly vertical, but irregular in detail. It is known to extend to a depth 1,200 feet below the original surface, but its area at that depth has not been determined. Ownership of this deposit is divided among three active Companies: the Asbestos Corporation, Limited; Bell Asbestos Mines, Limited; and John-son's Company. Johnson's Company owns a section about 1,000 feet in length and 500 feet in width, bounded on the northeast by the King mine of the Asbestos Corporation and on the northwest by the Bell pit. On Johnson ground, there was originally a large outcrop o~ asbestos rock which dipped toward the south below overburden. This was mined until recently by open pit, the overburden being stripped off as far southward from the original outcrop as was economically possible. As the. pit was deepened, within side walls maintained at a maximum safe slope, its floor area, of course, became progressively smaller, and eventually the pit would have wedged out against the Bell property line. It became necessary, there-fore, to introduce some other method of mining before production became seriously curtailed by a shrinkage of the pit area.

Jan 1, 1941

By R. Yang

This paper presents a kinematic approach for blast modeling with examples of blast models that were developed previously. A kinematic approach was applied successfully in developing blasting models that can simulate all blast design parameters for field applications. Several applied blasting models have been developed and applied widely in the world. A kinematic approach to blast modeling refers to using measurements of kinematic quantities such as the velocity, strain, or displacement and well-established assumptions to model blasting phenomena, rather than being restricted to use first principal of physics, such as, the stress- and material-constitutive relations. The kinematic quantities are easy to measure in the field. Due to the complexity and inhomogeneity of rock mass properties, using first principles of physics, many parameters of rock and explosive properties must be involved, which are hard or impossible to quantify. This creates a major impediment when trying to simulate the total process of blasting based upon first principles of physics. The 3D kinematic model for muckpile formation was developed and applied to open pit blasts. The multiple blasthole fragmentation model developed during recent years has been applied successfully to many mine sites around the globe. These models are typical examples of blast modeling using the kinematic approach, which enables the models to catch major trends of the blasting process and explicitly simulate full blast design parameters and complex geometries. Blast modeling using the kinematic approach results in easy model calibration and validation against field measurements and effective applications to practical problems. Using kinematic models of the muckpile formation and the multiple blasthole fragmentation model, this paper demonstrates the merits of the kinematic approach for blast modeling. New developments of the models were also presented in the paper, which illustrate the potential of the kinematic modelling approach.

Mar 2, 2022

By Qinghua Gu, BUQING XUE, XUEXIAN LI, JIANGSHAN SONG, Qian Wang

To solve the problem of time-consuming and low precision in updating the open-pit vehicle transportation network, a high precision road network model construction method for unmanned vehicles in open-pit mines is proposed. This method can be divided into two steps. In the first step, an improved deep learning image processing model named DeepLabv3 + C (DeepLabv3 + Concat) is presented. Then, the road information extracted by the DeepLabv3 + C network is used to construct a three-dimensional model of the open-pit mine road network. In the second step, aiming at the time-consuming problem of unmanned vehicle meeting in open-pit mines, a vehicle meeting strategy was proposed. This strategy is used to guide the navigation of unmanned vehicles in open-pit mines. Besides, the DeepLabv3 + C network is verified by comparing the mIOU (means Intersection Over Union), accuracy, and continuity of road image extraction with the mainstream networks. The road network model constructed in the first step is quantitatively analyzed, and its performance is compared with GPS trajectory clustering methods. At the end of the paper, vehicle running simulation is carried out on the road network model by using Unity (a 3D visualization simulation software). The results show that the road network model constructed by this method can meet the navigation requirements of unmanned vehicles in open-pit mines, and the feasibility of the vehicle meeting strategy is proved.

Jan 11, 2022

By W. B. Boggs

The Noranda smelter was built by Noranda Mines, Limited, from the designs of A. E. Wheeler, consulting metallurgist, New York, for the reduction of ores and concentrates from the Horne mine, and to treat, on a custom basis, ores and concentrates from other mines in the Rouyn district. The smelter is situated at Noranda in western Quebec, about 330 miles directly north of Toronto. Ground was first broken for construction in November, 1925, before the completion of the branch railway into the district, which was not finished until October, 1926. After many difficulties and delays due to the Jack 'of transportation and the severe weather during the winter months, the smelter was started in December, 1927, and the first blister copper was poured on December 17th. The smelter was built throughout in two duplicate units, each with a rated capacity of 500 tons of ore per day. Operations were started with only one unit, and after several months it was found that one unit alone would smelt 1,000 tons of ore per day. At this time only one shaft, No. 3, existed, and its hoisting capacity and the capacity of the original crushing plant were insufficient to supply ore for two units at the increased tonnage. Accordingly No. 4 shaft was sunk and a new crushing plant provided to handle the ore hoisted there. This work was completed in the latter part of November, 1929, and since that time both smelter units have been operating.

Jan 1, 1930

By J. S. Hansen

To advance technology that can conserve critical materials, the Bureau of Mines investigated a cast-on hard-surfacing that wear resistance and confines alloy additions to wear-prone surfaces. Wear-resistant material in form is on a polystyrene , the is embedded in a mold of unbonded s and the wear-resistant material is transferred to a cas surface at the time of For low-stress abrasion, derived from high-carbon ferro-chrome had higher wear resistance than did commercially available weld-hard. The microstructure of the was typi-white iron carbides. Free carbon added to the ferrochrome powder produced more M7C3 carbides than did material contained in surfacings made from ferrochrome alone, and improved the wear resistance. Several white iron powders with greatly reduced chromium contents also white iron contain-M7C3 carbides. One derived from white iron powder had wear resistance to that of weld-deposited hard facings. Among the parameters investigated, surfacing thickness was found to have a or influence on diffusion of elements out of the , microstructure, and wear resistance. The results of field tests on bucket-wheel excavator teeth and plowshares with cast-on hard surfacing are given.

Jan 1, 1985

By M Thompson

"The Jaguar concentrator, 60 km north of Leonora, Western Australia (WA), consists of a standard closed circuit semi-autogenous grinding (SAG) and ball mill producing a float feed of approximately 60 micron at 70 t/h. Following comminution, separate copper and zinc concentrates are produced by differential flotation. These concentrates are subsequently dewatered by thickening and then filtration.Separate audits of the Jaguar Operation’s copper and zinc concentrate thickeners were conducted to evaluate their performance, following occasions where site personnel had identified unnecessary loss of copper and zinc concentrate to the thickener overflow. The feedwells were identified as the source of the observed problems due to the following issues with their design/duty:lack of retention time in the feedwell as current design is completely opennot conducive to effective mixing required for efficient flocculationdiameter of the zinc concentrate thickener feedwell was undersize for its duty.To improve the performance of the thickeners, it is planned to replace both concentrate thickener feedwells with a high rate design for their respective duties in February 2016. The audits also identified that the feed system requires modifications with particular importance placed on minimising air entrainment of slurry into the thickener feedwell. Minimisation of air entrainment is hoped to be achieved by providing constant head pressure through installation of weir arrangements in the feedboxes and redirecting each feed pipe so that it feeds tangentially into the feedwell. In addition, improvements to the control philosophy of both thickeners will be made with the installation of an ultrasonic bed level probe and bed mass sensor, in order to make real-time adjustments to the underflow pump speed to maintain steady state operation.Following the feedwell replacement and modifications to both thickeners it is expected that losses of recovered copper and zinc will decrease to undetectable levels. Subsequently it is anticipated that a more consistent, homogenous underflow can be produced for downstream filtration.Citation:Thompson, M, 2016. Concentrate Thickeners Feedwell Replacement, in Proceedings 13th AusIMM Mill Operators’ Conference 2016, pp 273–278 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Oct 10, 2016

By Mohan Dutt

This paper is concerned with applied platinum resistance thermometry which involves many considerations absent in precision thermometry. The historical development of the Callendar-Van Dusen Equation which describes the resistance- temperature relation of pure platinum is discussed. The advantage of using platinum resistance temperature sensors over thermocouples is described, and the improvements in design and construction of these sensors that have come about in the past few years are discussed. Integral and remote bridges that convert resistance changes into voltage together with signal conditioning techniques and equipment for voltage or current signals are described. Errors encountered in temperature measuring schemes and methods to reduce these errors are summarized.

Jan 1, 1969

By A. C. Johnson

This report is one of a series being prepared by the Bureau of Mines on exploration, development, mining methods, and costs at various mines in the United States. It describes operations at the Black Rock mine, Wah Chang Mining Corp., Mono County, Calif. The purpose of these reports is to promote development and conservation of our mineral resources by disseminating technologic information on mining methods, practices, and costs. The Black Rock tungsten mine of the Wah Chang Mining Corp. is 33 miles north of Bishop, Calif., in the Benton Range, Mono County, Calif. The property was acquired in August 1950 and a well-planned program of exploration, development, and exploitation resulted in a good production record with low costs. Operations were halted in July 1957, about 6 months after suspension of the tungsten purchase program by the Federal Government.

Jan 1, 1960

By Thomas Kuhn

Germany?s industry heavily depends on the continuous import of mineral commodities such as manganese, copper, nickel, and molybdenum. Due to the strong increase in metal prices since 2002 Germany?s federal geological survey, the Bundesanstalt für Geowissenschaften und Rohstoffe (Federal Institute for Geosciences and Natural Resources, hereafter called BGR) applied for a license area for the exploration of deep-sea manganese nodules in the Pacific manganese nodule belt between the Clarion and Clipperton fracture zones. A 75,000 km2 covering license area was eventually granted to the BGR by the International Seabed Authority (ISA) in 2006. It is separated into two parts: ?W1? (17,000 km2) and ?E1? (58,000 km2; Fig. 1). The BGR obtained initial information on the abundance and grade of nodules in the license area from samples collected during three cruises with R/V Valdivia and one cruise with R/V Sonne between 1976 and 1978 (Rühlemann et al., 2009). Since the accuracy of navigational data obtained during these cruises is outdated and sample coverage is unevenly distributed and sparse in many parts of the license area, BGR has started a new exploration program to investigate the German license area according to the rules, regulations and procedures issued by the ISA for the exploration of Mn nodules in the Area.

Jan 1, 2010

By Dominic Parmantier, Jason Page

"In the past, the designers of DSM have analyzed various failure modes and then specified a minimum unconfined compressive strength (UCS) for the soil-cement. The specified minimum UCS reflected the compressive stress in the soil-cement under design loads and an appropriate factor of safety. With the increased use of finite element analysis for the design of DSM applications where allowable strain as well as stress are considered, there is a growing trend for designers to specify a modulus and occasionally a tensile strength for the soil-cement in addition to the UCS. This paper compares the relationship of modulus and tensile strength to UCS for soil-cement from a recent DSM project with unique testing requirements. These results are compared to published data. The case is made that designers should utilize published relationships to characterize the required strength and stiffness by a single acceptance criterion: UCS.INTRODUCTIONAs the use of DSM has increased in popularity so has the use of service state deformation analysis in lieu of more traditional failure mode analysis. Most DSM designers are interested in the appropriate modulus values and occasionally tensile strength values of soil-cement as well as simply the unconfined compressive strength (UCS) of soil-cement.Although there are numerous published correlations between the UCS, tensile strength and modulus of soil-cement, some DSM project specifications are produced which have acceptance values for tensile strength, modulus, and UCS. If this specification of multiple strength properties is consistent with the nature of soil-cement, then there is really no harm except for the expenditure of client money on unnecessary testing. If however the multiple strength properties specified are inconsistent with the material properties of soil-cement, then the specifications can create the expectation that the DSM contractor can somehow create a custom soil-cement with tensile strengths and modulus characteristics which are unachievable.This paper presents a brief summary of a project in Burnaby, B.C. which specified minimum values for the tensile strength, modulus, and UCS of the soil-cement. A comparison of those test results to published correlations between the UCS and the tensile strength is presented. Additionally, a comparison of modulus derived from two different methods of testing is presented along with a comparison to published correlations between UCS and modulus for soil-cement."

Jan 1, 2015

By P Hanna

Following the Busang fiasco, more detailed guidelines were appended to the latest revision of the JORC Code released in September 1999 (JORC, 1999). Although the definitions and terminology essentially remained unchanged, the additional information in the guidelines has highlighted a number of issues for consideration by geologists undertaking computer-based resource estimations. The three main issues are:Data Integrity û details such as drilling and logging techniques, sampling procedures, assay tests, site visits, data recording and aggregation methods need to be considered. Geological Interpretation û is the Competent Person applying the appropriate software interpretation to the deposit in accordance with the regional setting. Are the correct computer-based tools being applied and are they producing the desired result (without compromise) to the satisfaction of the Competent Person? Modelling Technique û the importance of the relevant experience of the Competent Person not only in regard to the geology, but also with respect to the modelling algorithms and resource calculation methods of the computer software system involved. At the end of the day, it is essential that the Competent Person undertake a reality check on the resource estimation itself. They should also check that the borehole spacing is in accordance with the level of continuity for each critical parameter (such as structure, grade, impurities, etc) for which the resources are categorised.

Jan 1, 2000

Certainly, one of the core processes for the recovery of fine magnetic susceptible iron ore particles, mainly hematite iron ores, is the wet high intensity magnetic separation or WHIMS. This paper outlines a variety of recent developments and innovative process designs in the JONES® type WHIMS. It highlights the latest examples of flow sheets in terms of the diversity of combined rougher, scavenger, cleaner stages and adds to this the new more advanced JONES® type WHIMS equipment technologies like the HIGH FLOW ? HF, the QUATTRO ? Q and the SPLITT OPERATION ? SP. As a result of the increase of the capacity and magnetic intensity, the specific production cost could be decreased. The high worldwide acceptance for this continuous development testifies for the success and state of the art technology.

Sep 1, 2012