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By H. V. Kinsey

"IntroductionTITANIUM is probably the most widely publicized metal today. Much has been written, both in the lay press and the technical press, about its properties and potentialities. In view of the fact that Canada possesses large quantities of titanium-bearing ore, and could conceivably become a major producer of metallic titanium, it was felt that a paper dealing mainly with the physical metallurgy of titanium would be of interest to this Institute. This paper is concerned chiefly with the useful properties of titanium and its alloys and the fundamentals governing the modification of its properties by alloying.Physical Properties of TitaniumTitanium belongs to a family of metals that have been termed 'gas sensitive' (I), because their mechanical properties are altered by certain gases which they readily absorb and retain. Other metals of this group are zirconium, hafnium, vanadium, columbium, tantalum, and chromium. Titanium has a strong affinity for oxygen and nitrogen and once it has absorbed these gases they cannot be removed either by melting in vacuum or by any degassing agent. These gases, when present in excess of about half a per cent oxygen plus nitrogen, render the metal brittle and useless as a structural material.Some of the typical physical properties of titanium are listed in Table I along with those of common structural metals for comparison."

Jan 1, 1953

By J. L. Kohler

Control circuit failures contribute significantly to continuous miner downtime. The time required to put the machine back into production is a function of the time required to diagnose the problem, obtain parts, and make the repair; of these, the diagnostic time is often the largest. A microprocessor-based system with the ability to diagnose all of the common control circuit failures was designed, installed on a continuous miner, and tested. This paper summarizes the development of the diagnostic system, and provides examples of the system's diagnostic capabilities. Implementation issues and the hardware used for the prototype are briefly described. Finally, comments on the system's performance are presented.

Jan 1, 1993

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Jan 1, 1983

By T. W. Turk, S. A. Sass

The engineering design features of the Mercur Gold Project crushing, grinding, carbon-in-leach, bullion, reagent, and tailings disposal areas will be discussed in this paper. It presents a project overview and flowsheet along with selected design alternatives. During the engineering phase, major equipment and other features were selected to optimize design within site location and environmental constraints. The project team organization and procedures were adopted to accommodate multiple optimization studies while maintaining a tight engineering schedule.

Jan 1, 1985

By Pinai Mungsantisuk

Keywords: Pd-Ni alloys, Pd-Fe alloys, Pd-Co alloys, Magnetostriction, Magnetic Properties The presence of congruent melting minima, the occurrence of ferromagnetic transition over a large composition range, and FCC type crystal structure make Pd-Ni, Pd-Co, and Pd-Fe based systems attractive candidates in our search for materials with no rare-earths, large low-field magnetostriction, and good mechanical properties. The presence of paramagnetic-ferromagnetic transition over a broad range of composition also provides opportunity for fundamental studies. In this work, we have examined the magnetic and magnetostrictive behavior of Pd-Ni, Pd-Co, and Pd-Fe alloys over the entire composition range. Alloy sample rods were prepared by arc melting and casting. X-ray diffractometer was used to obtain lattice parameter data. Magnetostriction was measured along the rod axis using strain gages. Magnetic properties were measured using a vibrating sample magnetometer.

Jan 1, 2005

By H. Powell

"This paper discusses how elemental analysis of conveyed bulk flows in real time using PGNAA (Prompt Gamma Neutron Activation Analysis) technology has resulted in significant improvements in advancing plant control in mineral processing operations. PGNAA through belt, full stream, continuous, multi-elemental, real time analysis technology is explained. Capabilities and limitations in plant operating environments are discussed including comparison with other real time, on-line technologies through review of published information available for on-conveyor minerals applications. Case studies include an iron ore and copper-gold company, both of which consider the technology an essential component in advanced plant control necessary in new process flow sheet designs, rather than an optimisation tool.INTRODUCTION Process operators rely on supply of a reasonable ore quality and consistency from the mine. Unfortunately neither the mining nor process operators have much control over the ore quality once it has been put into the crusher. Grade control typically stops once the material is designated as ore and the process plant operator needs to process it irrespective of quality. Plant control is most effective when technologies measure process streams directly and preferably in real time. Measuring sampling streams that are not representative of the primary flow will result in incorrect plant control decisions. Sampling coarse conveyed flows is expensive and impractical at many operations, however, this does not mean those flows cannot be measured. Investigations to find techniques suitable for real time elemental analysis have focussed on the application of known laboratory techniques to process streams. For conveyed applications, development of neutron irradiation techniques were most promising and early studies indicated potential success for bauxite measurement (Beurton et al, 1995). Tran & Evans (2001) concluded there was no equivalent technology to PGNAA in terms of material penetration power and that the technology was eminently suitable for basic industries such as cement. Nelson and Riddle (2003) evaluated PGNAA for possible use in the phosphate industry by using a unit installed in a cement plant to test performance on phosphate samples and ultimately recommended its use for further characterisation of the mine’s various ore types to improve stockpile allocation and grade control"

Jan 1, 2014

Anglo Platinum commenced commercial underground borehole radar (BHR) surveys during 2006 following a series of trial surveys using both the ?slimline? Geomole and Aardwolf systems. Current borehole radar systems comprise radio frequency transmitter ? receiver antennae operating at 30 -100MHz that measure the time taken for a transmitted pulse to traverse a rock volume and be received (Fig 1). The time taken can be converted to distance if the transmission speed of the pulse through the rock volume is known. The transmitted pulse may be reflected off a suitably orientated geological reflector (in reflection mode) or may be recorded in receivers located in other boreholes (cross-hole tomographic mode). In the Bushveld Complex lithologies, these radar systems have ranges of 30-50 metres in reflection mode depending on the electrical properties of local stratigraphic units. Both the Merensky Reef (MR) and the underlying UG2 have been shown to act as reflectors, which offer the opportunity of using BHR as an imaging or mapping tool. Reflection of the radar signal occurs wherever a strong contrast in dielectric constants occurs such as between norite and harzburgite or where chromitite stringers are present. [ ] Fig 1 Main elements of a borehole radar system Much experience has been gained in the practical application of BHR surveys in platinum mining. The value of a BHR survey is that it provides a continuous line of information to ?connect the dots? rather than a few discrete pierce points. BHR surveys can be used to mitigate risk in three crucial areas: ? Mine planning at the strategic as well as tactical level ? geotechnical evaluation of proposed shaft sites, detailed profiling or mapping of reef and disruptions of the reef such as faults, rolls and potholes; ? Mineral resource classification ? identification of structural discontinuities in orebodies affecting resource classification e.g. potholes and reef facies; ? Safety ? identifying areas with poor ground conditions that are often associated with faults, dykes and potholes.

Jan 1, 2007

By AIME AIME

THERE is a constant reiteration in some quarters that technical societies are autocratic and that democracy is utterly lacking and that members would welcome democratic societies in which they had full, control of affairs. While we may not speak for other societies, than our own, in so far as th's Institute is concerned such charges- can only come from people uninformed as to the circumstances. It. is no curtailment of the democratic privileges of the members that a -slate is prepared by the Nominating Committee to be voted on at the annual meeting. The Constitution of the, institute stipulates how the nominating committee shall; be chosen and who shall compose it, which prevents anything like- a- clique controlling- the situation. The Constitution further provides how the nominees shall be distributed geographically and the by-laws specify geographical boundaries: for-these nomination districts. Further more, any man or complete ticket can be placed in nomination by means of a petition signed-by only; twenty-five members,- and three or four times such an independent slate has been so nominated and elected.

Jan 1, 1920

By John W. Chandler

The property of the lava Cap Gold: Mining Corporation is in the Nevada City-Grass Valley mining district about 5 miles east of Crass Valley, Calif. At present (July 1940) the plant is mining end milling about 390 tons of gold-silver ore a day; about 310 men are employed. This paper describes the mining methods used and presents mining costs for 1939, when 60,704 tons were mined by cut-and-fill stoping and 55,676 tons by square-setting.

Jan 1, 1941

By Bruce I. Thomas

The Fairbanks mining district forms an arc 40 miles long and 8 miles wide on the north side of the Tanana Valley in central Alaska. This is a region of broad valleys and rounded hills that range in elevation from 600 to 2,600 feet Lode-gold production started in 1910 and has continued sporadically to the present, but the largest single mine produced only 40 tons per 24-hour day. Total recorded lode-gold production of the district is 241,000 fine troy ounces of gold from ore that averaged 1.32 fine ounces per ton. The ore was mined chiefly from narrow veins and veinlets alined along anticlinal folds at Ester Dome and the Pedro Dome-Cleary area. The only proven reserves are reported to be at the Ryan Lode at Ester Dome and at the Keystone Mines, Inc., holdings in the Pedro Dome-Cleary area. An inferred lode-gold resource for the district of approximately 4,000,000 ounces is considered to indicate only the order of magnitude of the lode-gold potential because of the absence of detailed data needed to evaluate the numerous deposits.

Jan 1, 1973

By S. Dessureault

The relatively recent explosion of available data in all business sectors has induced a common expression of “drowning in data, starving for information.” The mining sector is affected by the information age through equipment-based sensors, process monitoring, and traditional enterprise data sources. Information technologists have developed techniques such as data mining that apply new and old statistical algorithms to large datasets. Mine planners and managers can apply these tools for improved planning and control, thereby increasing the use of the highly underutilized information system infrastructure in most modern mines. This paper describes the use of data mining and its enabling technology, data warehousing, in the development of an energy consumption model for large surface mines using real historical data.

Jan 1, 2007

By William Gleason

"Modern society demands much more from the mining industry than just the raw materials it produces. In addition to providing copper, gold, coal and other minerals that make society function, the industry must conduct its operations in a safe and environmentally sustainable manner. This includes the equipment used and the engines that power the machines.In the United States, Tier 4 diesel engine standards that were set by the U.S. Environmental Protection Agency (EPA) are the strictest emissions requirement for off-highway diesel engines. This requirement regulates the amount of particulate matter (PM) and nitrogen oxides (NOx) that can be emitted from an off-highway diesel engine. In Europe, the Euro V standards are driving technology advancement in the sector.The European Euro V standards are required for new equipment manufactured beginning in January 2019. U.S. Tier 4 standards for heavy-duty off-road engines came into effect with model-year 2014 vehicles and equipment. China 6 standards come into effect in July 2020. India’s Bharat Stage VI standards will take full effect in 2020, and the phase-in of BSVIcompliant clean fuels began in April 2018.Caterpillar, Cummins and MTU are three of the leading manufacturers of engines for the mining sector. Each company is working toward creating efficient engines that can function in the often harsh environments found at openpit and underground mines around the world. In short, society is placing demands that are challenging engine manufacturers to deliver a product that can do more work while consuming less fuel and emitting fewer emissions.Technologies range from selective catalytic reduction (SCR) and diesel particulate filters (DPFs) to other engine strategies and emissions control technologies, which deliver near-zero black carbon and nitrogen oxide emissions, and lower greenhouse gas emissions. Caterpillar’s investmentCaterpillar, the world’s largest producer of mining equipment and mining engines, has been at the forefront of the changing demands placed on the industry and has remained on the cutting edge of engine development over the years, thanks to its investments in the sector.“Caterpillar made the choice to fund major engine and machine development work — even during a deep trough in the mining industry — so that Cat machines would meet Tier 4/EU Stage 5 mandated compliance dates of Jan. 1, 2018 / Jan. 1, 2019, respectively. For Caterpillar, these efforts enabled our mining trucks to provide improved engine component life to help our customers’ total cost of ownership (TCO) and produce a neutral TCO compared to our Tier 2 products,” said Jeff Castleman, new product introduction manager, large mining trucks for Caterpillar."

Aug 1, 2019

By Remco Offenberg, Marcel Bielefeld, Martijn van Delft

The question of the continued suitability of existing foundations arises when the function of the superstructure changes. This can occur when the superstructure is replaced or when the existing structure is expanded, leading to higher loads on the existing foundation. Quite often it is a challenge to define the suitability (with respect to integrity, bearing capacity or both). The lack of information on the existing foundation (such as pile dimensions, installation records, original soil investigation, design calculations, etc.) makes it frequently seemingly impossible to assess whether the foundation or foundation elements can be re-used. The paper outlines the tools available to an engineer to evaluate existing foundation piles for potential re-use. The paper illustrates the application of these tools through a few case studies from The Netherlands, including the evaluation of a 400 years old bridge foundation to address increasing traffic loads.

May 1, 2022

By T. Onnela

Metso Mining and Construction Technology is one of the world leading suppliers of equipment and knowhow for aggregate and mining industry. The processing capacity, ease of use, and reliability are featuring Metso?s state-of-the-art cone crushers. Crushing is a complicated process affected by numerous parameters. The optimized crusher kinematics is one of the key factors for high performance. To fine tune the crusher kinematics and crushing chambers one needs to know how different parameters affect. The main cone crusher parameters are head angle and diameter, gyration point, shaft speed, eccentricity, stroke length, and inclination and design of crushing cavity. Selecting the correct combination of these parameters is a multi task optimization challenge. In practical life there are more factors to achieve satisfactory performance, like crushing chamber wear and profile management keeping the performance constant over the whole wear life, control of crusher frame loads, ability to handle disturbances in feed material etc. The extensive research work has lead to a solution that enables the highest possible material density in the crushing chamber. This design provides maximum reduction of processed material and thus increased share of 0/10 mm product. High density in the cavity offers further benefits, such as high throughput capacity, less material contact with wear parts and even load on crusher frame and bearings. The challenge that an equipment supplier involved with high density crushing is how to design a robust cone crusher, which is able to cope with the high crushing forces due to high resistance from the crushed material against the gyration movement. Metso has launched a new series of cone crushers HP3, HP4 and HP5 that are all able to work in high density crushing applications The test results and evidence from over 300 installations clearly prove the effectiveness and importance of high density crushing. Keywords: cone crusher, crushing chamber, crusher kinematics

Sep 1, 2012

By E. B. Freidina

We have investigated a new electrochemical process for preparing lead-calcium alloys. Calcium metal, reduced fiom a molten chloride mixture, forms an alloy with liquid lead cathode. The addition of calcium carbonate to conventional CaC12-NaCl electrolyte enables us to avoid chlorine production on the anode and replace it with oxygen and carbon dioxide. The ternary system CaClz-NaC1-CaCO3 has a range of melt compositions, where the electrolysis can be held below 650°C. In order to prevent the side reaction of carbon deposition on the cathode we have separated the anolyte from the catholyte with alumina diaphragm. The factors, which affect the level of impurities and the current efficiency of the process, are discussed.

Jan 1, 1999

By Stephen G. Mlot

The evaluation of mineral projects involves the identification, mitigation and management of significant uncertainty. Benchmarking is an essential and effective way of increasing confidence and reducing uncertainty associated with input parameters and assumptions. Comprehensive and detailed benchmarking will ensure ?best practice? technologies, methods and systems have been considered and that the appropriate practices can be identified and incorporated into the project. In conjunction with the involvement of experienced industry practitioners, benchmarking is best employed throughout project evaluation to enable early identification of ?errors?, producing more accurate and predictable outcomes. Considerable time and effort is required to gather data and information, which should be benchmarked by the project evaluation team. There is a history of mining projects underperforming, on production, on costs and on return to the investors. The quality of mine plans and feasibility studies, and the quality of the input data is being questioned in many ways. Benchmarking assists sound project evaluation practices, by providing a database of actual results, to validate project inputs and outcomes, ensuring they are realistic and achievable. Benchmarking also provides unbiased, statistical support as the basis for sound investment decision making and ensures well considered decisions are made resulting in a more efficient study process. The evaluation of the quality of projects which are the subject of transactions also benefits from the use of real data obtained from a benchmarking database. Vendors are quick to highlight the benefits of their projects, and conceal the flaws, inflating the value. Buyers will want to quantify the potential of a project through the due diligence process relying on actual results from benchmarking. For the reasons broadly outlined above, benchmarking should be considered as an essential component of effective Project Evaluation.

Aug 1, 2013

By M. A. Trevits

Mine seals are used in underground coal mines throughout the United States to isolate abandoned mining areas from the active mine workings. The objective of adding inert gas to a sealed mine area is to quickly reduce the oxygen concentration in the sealed area to a level that will not support combustion. In the US, this process is typically conducted from the ground surface and because surface-to-mine access is constrained by so many variables, it is very difficult to provide a source of inert gas to the place where it is needed underground. To alleviate this problem On Site Gas Systems, under a NIOSH contract, built a nitrogen (N2) generation plant that operates in the underground environment. The purpose of this work was to create a reliable in-mine mobile plant that would extract N2 gas from the mine atmosphere and use the gas to create and maintain a safe sealed mine area. The plant is based on a novel design using pressure swing adsorption technology and is sized to fit on a standard shield car or mine dolly for easy transport in and around an underground coal mine. The plant is capable of producing about 900 scf/min of N2 gas at ambient mine conditions. After an exhaustive series of laboratory tests, the plant was field tested at the NIOSH Safety Research Coal Mine (SRCM) where a portion of the mine was sealed and rendered inert. During the test, the movement of the injected gas was monitored at several underground points to observe the progress and extent of the inerting process. This paper describes the plant design and the results of the field test at the SRCM. Disclaimer: The findings and conclusions in this report are those of the authors and do not necessarily represent the views of NIOSH.

Jan 1, 2009

Sulfidisation Promotion Effect of Ammonium Sulfate on the Flotation of Copper Oxide Ores

Sep 13, 2010

By W. H., Bassett

IN January, 1926, the writer began a study of the commercial value of beryllium in its relation to copper. The purpose of the investigation was not to make a mere laboratory study of the characteristics of beryllium-copper alloys, but to determine under mill conditions the behavior of copper when alloyed with beryllium and when other metals were added to such alloys; in other words, it was considered important to know whether the alloy bars could be hot-rolled or cold-worked, and what limits in composition would have to be established for these two methods of working. Consequently, more stress has been placed on the practical application of the alloys in engineering and commercial use than on a discussion of the metallography of the specimens examined, although this part of the matter has not been entirely neglected. Credit should be first given to G. Oesterheld,1 who, in 1916, published the copper-beryllium equilibrium diagram. Fig. 1 has been copied from the original article with the simple substitution of English words. It will be noted from Fig. 1 that alpha solid solutions are formed, up to about 1.5 per cent. Be (10.5 atom.). The freezing-point curve, after falling from 4.2 per cent. Be (23.5 atom.), enters into a very complicated form over the entire beta region. There is a possible compound, Cu2Be, at about 6.5 per cent. Be (32.3 atom.). The pure gamma range extends from 11.2 to 12.2 per cent. Be. (46.5 to 49 atom.), after which the liquidus rises rapidly to 30 per cent. Be. (75 atom.). The delta solution extends from 25 per cent. to an unknown percentage of beryllium. There is a eutectoid point at 575" C., extending from 1.5 to 11.2 per cent. Be., the maximum time interval of which occurs at 6 per cent. Be. Below this line the beta solution is described as breaking up into alpha and gamma. Microscopically, the eutectiferous alloy thus formed closely resembles pearlite, and requires a high magnification for its resolution.

Jan 1, 1927

By William Reisz

Many different types of drills coming in a wide range of sizes and configurations are used in the blasting industry today. While each system may have its own unique attributes and capabilities, it may hold its own perils as well. This article will focus primarily on hazards that are mutual to most every type of drilling system.

Jan 1, 2013