Search Documents

By Bert S. Hall

"The purpose of this paper is to review the evidence at hand concerning the earliest centuries of cast iron in Europe, from roughly 1400 A.D. until the second half of the sixteenth century. For the most part it is concerned with the relationship between two technologies which emerged first in China and then later appear in Western lands, gunpowder weapons and iron founding. We should not assume, as I hope to show later in this discussion, that weapons constituted the only product for which the iron founder had any market, but it is clearly true that attempts to produce weapons constituted the most severe technical challenge for the early founder. Firearms appear for the first time in Europe in the 1320s and develop into significant weapons on the field of battle by the end of the century. Theirs is a complex history, subject neither to easy summary treatment nor to simplified models of development. I hope to be able, through the analysis of the evidence concerning cast iron, to show that one important strand in the fabric of gunpowder's history concerns the materials from which cannon could be made. This question is subject to a number of shades of meaning, because ""cannon"" can be made for many purposes under a profusion of different names, and under sharply varying conditions of use. As a result, the question of materials is frequently really a question of competing materials, and involves a complex set of factors, of which production costs and the ultimate safety of the user seem the most important. Judged in this manner cast iron was an important but unsatisfactory metal for weapons purposes until 1543, at which time English founders learned to make iron muzzle-loading cannon which could rival bronze ordnance in most important performance criteria, but which cost much less to produce. With that event, the history of cast iron and the history of weapons entered into the close relationship that persisted until the advent of rifled artillery made of steel in the middle of the nineteenth century."

Jan 1, 1999

By Staff

One hundred thousand miles of flying over the North country without a single air casualty; much of it over virgin territory probably never before visited by white men; some of it over regions that abound with possibilities for minerals; all of it effective, for exploration and the establishment of bases and supply-stations, and for the carrying of men and their tools and provisions- this, briefly, is the record of Northern Aerial Minerals Exploration, Limited, a Canadian company organized Jess than nine months ago, which has been functioning, without interruption, during spring, summer, and now into winter. Our planes have ranged from the Alaskan boundary on the west to the Labrador coast on the east, and from the Transcontinental railway north to the Arctic circle. Our prospectors, carried on trips of hundreds, and occasionally thousands, of miles, have gone over large sections of country which were never before explored, and at the end of the prospecting season the Company finds itself in possession of several groups of important gold claims, which look most promising. In addition to this, we have been in contact with deposits of almost every known mineral.

Jan 1, 1929

By J .. A. Nemes, I. Ragai

This paper discusses one of the common problems associated with sheet metal forming processes, which is spring back. The materials presented here, stainless steel 410 and Inconel 718, are commonly used in aerospace applications for their superior material properties. Standard tensile tests were performed to determine their tensile properties, as well as material anisotropy. In addition, the effect of anisotropy on springback was assessed experimentally through simple multiple-bending experiments in different directions to the rolling direction. Finally, draw-bending experiments were carried out to study the effect of forming conditions, such as blank holding force, on the final springback angles of the formed parts. For both materials, it was found that the R-values measured for different sheets exhibited variation. However, the specimen orientation does not have a large effect on material tensile behavior or springback angle for simple bending. For the Inconel 718 specimens, the springback angle slightly increases with each stage of deformation during multiple bend experiments. The effect of the blank holding force on springback angles was also examined and found to have a significant effect on thin specimens.

Jan 1, 2006

By M. Greyling, C. Panaou, M. Bellino

Commonly the most frequent method of calculating the overall mass balance of a multi mineral platinum-group metal (PGM) concentrator circuit in Southern Africa has been through the use of spreadsheets, typically Microsoft EXCEL®. While there are some advantages in using spreadsheet based mass balances during the conceptual design phase of the project, their use becomes limited in the detailed design phase of the project. This paper discusses the successful application of METSIM® for mass balancing of a PGM concentrator and highlights the benefits gained during the conceptual and design phase of the project.

Jan 1, 2005

By R. E. Johnson

Seventy years after the start of the Industrial Revolution in Great Britain, as reckoned from Arkwright's water frame patented in 1769, there was a significant development of the metallurgical industry in Virginia. In Britain, crucible steel had been rediscovered by Benjamin Huntsman in 17~0, and this made spring and tool steel more generally available. The metal-turning, screw-cutting lathe, including the basic principles recognized in today's engine lathe, was developed by Henry Maudslay about 1797. Wrought iron, as manufactured by Henry Cort's process patented in 1784, was readily available. Richard Trevithick's highpressure steam locomotive had met its test on the Pennydarren tramroad in 1804, and George Stephenson had built his famous Rocket, along with several other locomotives, at Newcastle around 1828. Puddling furnaces and a rolling mill had been placed in operation at the Tredegar Iron Works in Glyn Sirhowy, Monmouthshire, Wales, in 1807. In the United States, expanding commerce and a growing population resulted in continuing development from the Chesapeake to Virginia's Blue Ridge, and this demanded improved means of transportation. Ore deposits rich in hematite had been found in Virginia's Piedmont during the Colonial period, and a number of blast furnaces now dotted that area. The products of these operations were mostly pots, kettles, stove parts and like items for local trade. The James River and Kanawha Canal was incorporated in January 1785. Its eastern leg, winding along the slope of the high bluffs overlooking the river, was completed about 1800. About two dozen railroads were chartered in Virginia between 1830 and 1837. With expanding population and steady industrial development came a need for metallurgical products. Throughout the eastern United States, numerous metallurgical enterprises sprang up, and many of these flourished. The purpose of this article is to outline the development of one Southern metallurgical company, the Tredegar Iron Works, which was to have a significant impact on the industrial development of Virginia and the fighting of the American Civil War. Although the Tredegar Iron Works no longer exists, remnants of the early operations have been restored, and the current status of the site is also presented.

Jan 1, 1999

By Jarrett. K. M.

Nobody has, as yet, made a perfect machine. Therefore, when a machine is operating and functioning as it is designed to do, there is always some vibration present. This is easily and simply measurable with present-day equipment and any increase in the amount of vibration will indicate a potential failure. When an increase is noted, vibration analysis can pinpoint the cause of the potential failure and remedial action can be taken before an unscheduled shutdown is necessary or a breakdown occurs.

Jan 1, 1972

By Nicholas C. Williams

This paper presents the development of a demand reduction and responsive strategy capable of reducing the electrical power demand, particularly during peak conditions. The work presented includes a case study of a UK colliery. Areas explained are the equipment installation at the mine; the development of the demand reduction strategy including the load profile database and prediction optimisation model. Some live production data from the power meter installation at the mine is also presented.

Aug 1, 2013

By D. C. Rance

"The Quintette Coal Limited property is located in the north east coal area of British Columbia. A basic agreement with the Japanese steel industry was ex ecuted on January 27, 1981 for the sale of 69.5 million tonnes of Quintette metallurgical coal over a 14.5-year period. This contract period can be extended by Jive years by mutual agree ment. Sale agreements have also been signed for the sale of 19.4 million tonnes of oxidized coal over a 15-year period. Work started on site development in the late summer of 1981, and at present, two of the four eventual pits-the McConkey and Frame-are under development. The pits are currently in a pres/ripping phase. These pits are notable for the stripping volumes that have to be removed from relatively small pit areas. in order to provide for the required detailed rapid short-range planning of these pits, engineering will be computerized, as will the truck dispatch system. The mining area lies 21.1 km from the plant site by road and the transport of raw coal LO the plant is by means of a highspeed conveyor system which has a total length of 13.4 km with a vertical drop of 740 m. The surface plant facility was designed on a modularized basis to facilitate maintenance, and is designed to enable the use ofgravity flow ofraw coal and heavy media in the plant to minimize the use of pumps. The construction of the plant and mine site facilities is on-going, and the first coal production is scheduled for early December 1983. Introduction Quintette Coal Limited is a Canadian company incorporated in the province of British Columbia in 1971. Denison Mines Limited is the manager of Quintette's activities. Equity in Quintette Coal Limited is held by several shareholders, with interests as follows: Denison Mines 'Limited, 500Jo; Charbonnages de France International S.A., 120Jo; and Japanese interest, 38%. The project will develop almost 120 million tonnes of coal for marketing during its first 20 years of production. All of the planned production tonnage has been committed to Japanese markets. Most of the coal will be metallurgical grade, and the remainder will be a high-quality thermal coal. The Mcconkey and Frame pits, which will initially provide the mine's production, will commence production in early December 1983 and will, in 1985, reach the full annual production of 5 million tonnes clean metallurgical coal and 1,380,000 tonnes of clean thermal coal."

Jan 1, 1985

By Nick Vayenas, Ming Cai, Hongbin Zhang Lorrie Fava, Enrique Acuña

"A hybrid methodology is proposed to improve the accuracy of Diesel Particulate Matter (DPM) concentrations simulated in a ventilation network model by using Computational Fluid Dynamics (CFD). DPM, as a primary concern for underground hard-rock mines, has been studied in two dominant numerical models, ventilation network solvers and computational fluid dynamics. Ventilation network solvers are efficient, but they are not able to provide three-dimensional DPM concentration contours and only accept area-average DPM data as input. CFD simulations are time-consuming, but generating DPM concentration results with high accuracy. Besides, both monitoring points and planes can be created in a CFD model, which can take both point data and area-average DPM data as input. The hybrid methodology is intended to combine the advantages of the two by using the CFD results to update the network model results at key locations. A field study was conducted in a dead-end heading in an underground gold mine in the United States. Real-time DPM monitors were used to collect data. A CFD model and a network model were built for the experiment area. The CFD model was calibrated to the experimental data. In the study presented here, results from a calibrated CFD model are converted to equivalent diesel emission rates in the ventilation network model at a shared outlet. The hybrid methodology is used to provide better input for the network model. INTRODUCTION Mine ventilation system is one of the most important parts for an underground mine. It not only provides fresh air to the personnel but also helps clear the contaminants generated from the diesel-powered equipment. For most underground metal and non-metal mines, diesel particulate matter is the main contaminant. It is also the focus of this paper."

Jan 1, 2019

By D. Royston

Reducing SAG Mill feed size has been a major trend in recent years. ?Mine to mill? strategies have reduced blasted-rock size, and in a growing number of operations reducing the primary crusher CSS and/or adding additional crushing upstream of the SAG mill have reduced rock feed size. While reducing feed size will increase SAG mill throughput, issues arise in terms of retaining charge in the mill, exposing the shell lining to impact damage, and maintaining milling performance should the pre-crush system shut down. This paper reviews the past experience on pre-crushing for SAG mills and provides an analysis of liner design (in particular grates and shell liners) for pre-crushed feed.

Jan 1, 2012

By T. W. Wlodek, Zygmunt Kowalczyk

In the period from 1946 to 1964, the annual output of co al from Polish mines increased from 4 7.3 to 117.35 million tons. In this paper, the methods of bringing about this increase in productivity through the building of some twelve new collieries (producing some 15 million tons annually) and the modernization, reconstruction and extension of some thirty-six older collieries are discussed.

Jan 1, 1967

By J. Bouchard, M. Levesque, D. Georges-Filteau, P. Radziszewski, G. LeBlanc

"Grinding mills are infamous for their extremely low energy efficiency. This paper reports the results of an investigation that characterized energy outputs in industrial grinding mill circuits. It identifies and discusses the potential for recovering energy from grinding circuits. Agnico-Eagle Goldex Division, Mine Canadian Malartic, and New Gold New Afton Mine participated in the study by providing operating data for three semi-autogenous grinding mills and four ball mills. Results showed that on average, 79% of the supplied electrical energy was converted to heat absorbed by the slurry, 8% was lost through the drive system, and approximately 2% was transmitted to the ambient air. Only 9% of the input energy was actually used for grinding. The remaining 91%—wasted as heat—could potentially be recovered using suitable technologies or integrated energy management systems. This topic remains to be further investigated. ¦ KEYWORDS Comminution processes, Energy recovery potential, Grinding mills RÉSUMÉ Les broyeurs sont tristement célèbres pour leur rendement énergétique médiocre. Cet article présente les résultats d’une étude qui caractérise les rendements énergétiques des circuits industriels de broyage et examine les possibilités de récupération d’énergie dans les circuits de broyage. La mine Goldex d’Agnico Eagle, Mine Canadian Malartic et la mine New Afton de New Gold ont participé à l’étude en fournissant des données de fonctionnement pour trois broyeurs semi-autogènes et quatre broyeurs à boulets. Les résultats montrent qu’en moyenne 79 % de l’énergie électrique fournie sont convertis en chaleur absorbée par la pulpe, 8 % sont perdus dans le système d’entraînement et environ 2 % sont dispersés dans l’air ambiant. Seuls 9 % de l’énergie primaire sont, de fait, utilisés pour le broyage ; les 91 % restants (perdus sous forme de chaleur) peuvent potentiellement être récupérés à l’aide de technologies adaptées ou intégrées dans des systèmes de gestion de l’énergie. Cette question demeure toutefois ouverte. ¦ MOTS CLÉS broyeurs, potentiel de récupération de l’énergie, procédés de comminution INTRODUCTION Grinding is largely recognized as a very inefficient process; energy efficiency estimates range from < 1 to 2% (Fuerstenau & Abouzeid, 2002; Tromans & Meech, 2002, 2004) when comparing the input energy to that required for generating new mineral surfaces. Criticizing an “ill definition of the reference for the output energy,” Fuerstenau and Abouzeid (2002) proposed a “more meaningful baseline” would be “the energy for producing new surface area by the ¬mens.” Based on this reference, they concluded that “the ball mill is reasonably efficient energetically,” exhibiting an efficiency of approximately 15% for quartz."

Jan 1, 2019

By W. J. Taylor, T. D. Parris

"Over 90,000 feet of raise have been bored at International Nickel underground mining operations throughout the Sudbury District since the advent of raise boring in the early part of July, 1964. With a total of 10 raise borers on hand at this time, techniques have improved steadily since introduction at INCO mines. The first unit, designed for use in rock of low compressive strength, had to be modified and redesigned to cope with Sudbury Area Precambrian rock. As equipment and boring techniques improved, a specially designed machine for larger holes was developed and is now in use. More powerful units, with a thrust capacity of up to 750,000 pounds, are under investigation. Raises have been bored up to 84-inch diameter, and the changeover to 5- and 6-foot flat reaming heads with improved cutter design has increased performance substantially. As a result, 5-foot-diameter raises have been completed to a length of 750 feet and 6- and 7-foot raises to over 500 feet. Reference is also made to the drilling of over 23,000 feet of drainage and sand-fill holes, ranging up to 7% inches in diameter, with smaller underground rotary drill equipment.Finally, a look into the future indicates the need for further improvements in equipment design to permit economic boring of 7- to 8-foot-diameter raises in Sudbury Area ground types."

Jan 1, 1972

By F. M. Clement

British Columbia, unlike the Prairie Provinces, cannot lay claim to vast prairies. She can, however, claim many valleys, uplands and plateaus that are capable of marked agricultural development. It has been said that British Columbia is not an agricultural province. This may or may not be true, but at the present time agricultural production in this province stands second only to that of forestry. The industry has advanced from a total production of 8 millions in 1908 to a total production of 60 millions in 1924, a total increase of approximately 650 per cent in 16 years. In the last 10 years production has increased from 30 millions to 60 millions. No other industry can point to such a rapid development. In 1908 British Columbia imported 12 million dollars worth of foods compared to the 8 millions which were produced at home. In 1924 she imported 20 million dollars worth of foods compared to the 60 millions worth produced at home. In addition we exported foods to the value of approximately 10 million dollars. British Columbia is therefore self-sufficing in-so-far as values ar.e concerned except for approximately 10 millions of dollars. It is not to be expected that this province will ever grow all the coarse grains that she may require: these, along with certain meats, will always be a heavy item in the imports. We are concerned at the present time more with the value of the products than with the quantities produced: in other words, with quantities only in-so-far as ? quantities improve value.

Jan 1, 1925

By C. R. Tang

The respirable dust real-time monitoring equipment export information is complex, and electromagnetic wave wireless transmission is affected largely under mine conditions. The respirable dust concentration information transmission method based on led light equipment is proposed. The respirable dust concentration data of the individual real-time monitoring equipment is encoded to fit the system transmission; the encoded signal is modulated onto the LED mine lamp; the light signal is transmitted by the spatial channel; the signal is received by the receiver to the photoelectric conversion to restore the respirable dust concentration data for subsequent processing. Simulation and verification experiments showed that the respirable dust concentration information transmission method based on led light equipment can achieve the LED miners? lamps visible light wireless data transmission.

Aug 1, 2013

By J. E. Gill

Introduction During the past summer, detailed geological mapping was extended to cover the entire group of 31 claims owned by Waite-Ackerman-Montgomery Mines, Ltd., and considerable new information was revealed by development and exploratory work underground. These new facts provide a more complete view of the lithology and structure of the area than has heretofore been available. They also necessitate revision of certain interpretations presented last year by Peale (l), and have served to straighten out some of the problems suggested by Porritt (2). The purpose of this paper is to outline in a broad way the relations as now understood and to discuss in detail certain points which should be of interest to members of the Institute. Maps and records by the mine staff have been freely used in arriving at the interpretation presented in the following pages. The writers are especially indebted to Mr. R. V. Porritt, the mine manager, with whom many of the problems touched upon were discussed on the ground and whose intimate knowledge of the geology of the underground workings aided greatly in testing various hypotheses. The writers have profited greatly, also, from close association with Dr. W. F. James during the course of the work. Permission to publish the included data has very kindly been given .by the management.

Jan 1, 1932

By I. M. Marshall

A review of technical literature covering Canadian mining emphasizes the advancement and changes that have been made in mining practice. However, current technical publications rarely outline basic principles or state definite rules that govern profitable mine operation. it may be argued that the broad principles of mining have long a go been outlined in various handbooks, text-books, and periodicals, and that these principles never alter. This is in great part true, but modern machinery, improved meta1-lurgical practice, and other advances, have in part modified these principles or changed the manner of their application. Many engineers hesitate to state specific rules, because it is so easy to quote an exception to a rules that any such statement appears to lose weight upon its very utterance. The exception to rules, and the reluctance to formulate rules, has forced such maxims as "the only rule in mining is the point of a pick," and "gold is where you find it". As an illustration of rules and their exceptions, one might quote the time-honoured maxim that a mill should not be built before a shaft has been sunk on a property in point of fact, Canadian mining history is replete with examples of wasted capital where a mill was built before a shaft had been bottomed. Y et this past year has seen a property enter profitable production whereon the building of the mill was started before the shaft was sunk. Instances such as this should not be accepted as evidence that a rule has been overthrown, but rather as an exception to the rule. The case cited pays tribute to the application of the diamond-drill combined with the correlation of sound geology. Incidentally, both these features emphasize a modern trend in the development of Canadian mining properties-a trend that is perhaps worthy of further comment. It is such trends that affect the principles of mining or modify their application. It is with such that this paper deals, at ]east in part. It is hoped that the statement of principles and the opinions herein outlined will be of sufficient interest to arouse discussion.

Jan 1, 1939

By K. E. Haque

"This paper is a brief overview of the role of oxygen in cyanide leaching of gold feeds (e.g. ore, concentrate). As the majority of gold occurs in the elemental state (Au °), its oxidation is of vital importance for dissolution in the cyanide lixiviant. The cyanidetion at high pH is favourable for the oxidation of Au° with a mild oxidant such as air or oxygen. Beside oxidation of gold, deleterious effects of soluble sulphides, arsenates, antimonates on cyanidation of gold can be alleviated by preaerating the leach slurry with air or oxygen (i.e. preaeration process).If gold is refractory due to its occlusion in sulphides, silicates, tellurides, etc. then gold liberation is possible by roasting in the presence of oxygen or by leaching under oxygen pressure. The data in the recent literature indicate that reactive oxygen supplied by H202, Na202, Ca02 or 03 during cyanidation can accelerate considerably gold oxidation-cyanidation and yield high gold recovery in much shorter leach time. The information compiled in this review leads to the conclusion that oxygen plays a vital role in the dissolution of gold in cyanide lixiviant."

Jan 1, 1992

By Jesus Garcia Iglesias, Jorge Loredo

"Abstract -The Asturian fluorspar district consists of vein and stratiform deposits where mineralization is controlled by a combination of lithological and tectonic factors.It is postulated that these fluorspar deposits have been formed under disequilibrium conditions created during circulation of ascending hydrothermal solutions along faults and other high permeability conduits. Mixing of solutions is inferred from fluid inclusion studies. Cavity filling and replacement processes are very important in localizing the ore deposits and in determining their morphology.Permian volcanic rocks in the area yield a regional positive geochemical anomaly in fluorine implying that Permian vulcanism may be a possible primary source of fluorine.On a regional scale a relationship can be established between some of the ore deposits and important tectonic lineaments. The stratiform deposits preferentially occur within a calcareous-detrital facies located at the margins of basins. These basin margins are related to important synsedimentary faults.Fluorite is the only economic mineral in these deposits. Quartz, carbonates, barite and pyrite are common minerals accompanying fluorite. Other minerals that may occasionally be present as minor components are: marcasite, chalcopyrite, fahlore, sphalerite, galena and related supergene minerals."

Jan 1, 1994

By Kazuhide Nakaniwa

In this research, we devised a measurement method using total stations (TSs) which have ?the Baum? which is a concentric circle reticle, as substitute for crosshairs. The Baum owes its name to the similarity between the concentric circles and trees (Baum in German). By setting one circle on both of edges of cylinders, operators can set their sights on points on the center line of the cylinders, and also can measure positional coordinates of the points. Also, by measuring two different points on the center line, operators can measure the position and tilt of the axes of the cylinders. Furthermore, we developed a pile driving navigation system. Foundation piles are used for various structures, and their forms are generally cylindrical. Especially, although it is difficult to drive tilted pile foundations, their usage are expected to expand due to their high earthquake resistance. Yet, a method to accurately measure the tilts of piles has not been established. However, we proved that operators can obtain adequate accuracy to control foundation piles through the measurement experiment using this system. Using this system, the information of the pile is measured using a TS, transferred to a PDA, and displayed from the operator?s view of the piling machine.

Aug 1, 2013