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"With a longstanding reputation for engineering expertise, Weir Minerals continually develops solutions and technology to better serve the mining industry. Recognizing that throatbush wear rate has a major impact on the overall efficiency of slurry pumps, Weir Minerals has developed superior rotating and axial adjustment technology.In many applications, the pump’s throatbush is the component that has the shortest life compared to the impeller and liners, with considerable variability.Adjusting the gap between the throatbush and the impeller front shroud reduces hydraulic recirculation in the pump. This prevents localized wear on the throatbush, improves hydraulic efficiency and lowers the total ownership cost for the operator. To avoid impacting the plant’s production, these adjustments are often performed while the pump is operating. However, this can have safety implications for individuals working at the front of the pump unit.“Manually adjusting an alloy throatbush on a large pump requires several people and is laborintensive. It requires mechanical tools to adjust the four pusher bolts, one at a time, in order to reduce the gap between the throatbush and impeller. We wanted to find a safer and quicker way to extend the wear life of the pump with regular adjustments, which led us to development of this technology,” said Marcus Lane, global product manager for centrifugal pumps for Weir Minerals.“Our automated throatbush adjustment solutions are available for pumps fitted with either rubber or alloy throatbushes on Warman slurry pumps used in the most arduous applications, and have been designed with our customers’ safety and pump operation in mind. By mechanizing the adjustment procedure, personnel are removed from the line of fire, and the accuracy of axial movement is increased,” said Ron Bourgeois, director of slurry pumping technology group for Weir Minerals."

Mar 1, 2019

By Robert B. Parsons

"Two recent decisions by the Canadian courts could reduce the taxes paid by many profitable mines in Canada. At a time when the mining sector is hurting from an ever increasing tax burden and soft prices, the results of two cases are welcome news. Mining companies are well advised to check prior years' tax returns in the context of these developments. IntroductionSince 1976, the income tax legislation has provided a reduced rate of tax for taxpayers engaged in the mining of mineral resources, through the mechanism of the ""resource allowance"". The deduction given for the resource allowance effectively reduces the federal rate of tax by one quarter on resource profits. In general terms, ""resource profits"" are defined to include a taxpayer's income from: the production and processing in Canada of ore to any stage that is not beyond the prime metal stage (or the pellet stage or its equivalent in the case of iron ore); and, royalties computed with reference to the amount of value of production from mining operations in Canada.In computing income from these sources, the taxpayer must deduct expenses that may reasonably be regarded as applicable to those sources, with the exception of expenditures for Canadian exploration and development or financing costs.As a result of the mechanics of the calculation of the resource allowance, one quickly realizes that the lower the expenses deducted from the resource profits, the higher the resource profits and consequently the higher the 25% resource allowance. The impact of the recent court cases is to narrow the range of expenses which are required to be deducted in the determination of the resource profits.The two cases are outlined below."

Jan 1, 1991

The Honourable Tony McGrady, Queensland Minister for Minerals & Energy and our local member; the Deputy Mayor of Mount Isa, Alderman Bob Moore; members and guests of the Australian Institute of Mining and Metallurgy; Ladies and Gentlemen; welcome to the Carpentaria and Mount Isa Region Development Forum.Withoutdoubtwearein an exceptional placeatan extraordinary time. In this region we have a numberofexistinganddeveloping mines, plus several major deposits in pre-feasibility oradvanced definition stage, and we continue to see further vigorous exploration. All this mining industryactivity is occurring against a backdrop of wider political, social and economic change, affectingmostofAustralia. The North West Queensland Branch of the Institute decided that the time was ripe for an open forum where issues involved with developing the region's assets be presented and discussed between members of the industry and also the general public.That then is the aim of this meeting: it is to be a place of learning and discussion about issues relevantto the developmentofthese deposits. To this end feel free to use the microphones in the aisles at question time to direct your questions to the speakers.

Jan 1, 1993

By Robert B. Parsons

"The Canadian mining industry is not off to a good start in the 1993/94 budget season. Of the five provinces and territories to table budgets as of March 31, 1993, the industry's scorecard shows: one win, one tie, and three losses.IntroductionBy the end of March, five of Canada's twelve provincial and territorial governments had tabled their 1993/94 budgets. The mining industry is off to a bad start. The industry's scorecard shows one win, one tie, and three losses. Only Newfoundland appears to be paying any attention to the industry's concerns about the impact of taxation on competitiveness. It is particularly disconcerting to see that non-profit based taxes continue to increase, at a time when these taxes are the focus of a united attack by the entire industry.NewfoundlandFirst, the good news. On March 18, 1993, Finance Minister Winston Baker announced the following changes to the province's mining tax regime:"

Jan 1, 1993

Mr. President, Ladies and Gentlemen, it gives me great pleasure to welcome you, on behalf of the Council and Administration, to this University and extend to you our very best wishes for a most successful and stimulating symposium. We as a College of the University of N.S.W. were always proud of the excellent support we received from your Institute members and the close association that existed between our organisations. Now we have matured into the University of Wollongong and have to stand on our own feet, we will need all the support we can get from such bodies as yours to ensure that we are not only producing graduates but are also playing a vital role in the community. Although there is no planning for a school of Mining Engineering in the near future, we do look forward to this being a viable proposition eventually and we will then be able to offer to your Institute wider facilities for your activities and ones which will embrace both the Mining and Metallurgy phases. Thank you Mr. President.

Jan 1, 1975

By Charles L. Hosler

My function here today is not to illuminate any particular subject but simply to welcome you to Penn State and to the College of Earth and Mineral Sciences. Our college is, of course, dedicated to the same thing to which most of you have dedicated your lives--the exploration of the earth, the extraction of materials from it, and the production of useful things from those materials. We have about 2,000 students engaged in studying in preparation for service in these activities at the present time. Like other colleges of our type, we've undergone a great expansion just at a time when university budgets are contracting. This creates an interesting situation as to how we can best use our resources. This, of course, is the thing a lot of you are going to be talking about here--how we can best use the world's resources. As you well know, the expectations of the people of the world are rising, and, with the numbers of people increasing and with finite resources, there never was a time in history when it was more important that we become "quantitative" in our discovery, estimation, extraction, and utilization of those resources. I think it is admirable and very timely that you are gathered together to discuss your various approaches to this particu¬lar problem of quantifying and making most efficient use of the resources of the world. Yours is sort of a hidden profession, not just because you actually go underground, but because the public in general is not aware of where the materials they use come from. If you are successful in your professions the public will continue to be unaware. Only if you fail will your essential function become patently obvious. I wish you success both in your professional pursuits and in this particular meeting.

Jan 1, 1977

By Carrie Smith

This fall, the Society for Mining, Metallurgy & Exploration (SME) will begin a new chapter by welcoming its new executive director and chief executive officer (CEO). Melissa Russell, a successful nonprofit executive with more than 30 years of experience in global association management, officially stepped into the role on Sept. 29, 2025. She succeeds longtime CEO Dave Kanagy, CAE, who is retiring in March 2026 after more than two decades of transformative leadership. “I am honored to begin this new chapter with SME and inspired by the vital role this community plays in shaping our world,” said Russell. “I look forward to listening, learning and working alongside this remarkable group of professionals to advance innovation, champion sustainability and create a brilliant future together.” Russell brings a deep portfolio of leadership experience in technical and industrial associations to SME. Most recently, she served as executive director of the Institute of Electrical and Electronics Engineers (IEEE) Computer Society, the largest of the IEEE’s 39 societies, with more than 50,000 members across 150 countries. During her tenure, she strengthened global engagement, advanced financial sustainability and launched strategic humanitarian initiatives.

Oct 1, 2025

By J. B. Caine

This year we are extending our educational experiment of last year to new fields. The subject to be discussed at the educa¬tional meeting Saturday morning has nothing to do with melting or metallurgy, but is electricity and how we should use it in the operation of our furnaces. Your Committee feels that all of us could know more about the fuel we use to make our steel. May I emphasize that this session is separate from the rest of the program; there is no registration fee; and I want to urge all of you, especially those in this vicinity, to bring your assistants to this meeting. It will be well worth your while.

Jan 1, 1947

By Allen V. Reicks

Modern conveyor pulleys are welded steel structures subjected to dynamic loads. In this paper, fatigue notch and fracture mechanics methods are applied to several weld joints on typical pulley constructions. These methods are used to analyze field applications and are correlated with laboratory testing. Generalized approaches are presented which provide high confidence in pulley design with corresponding high reliability.

Jan 1, 1996

By H. Saari, M. Pates, P. C. Patnaik, A. Merati

Single crystal nickel-base superalloys such as PWA1484 exhibit superior performance compared to conventional superalloys, and are used extensively in turbine blade applications requiring good high temperature properties. The life of these blades is typically limited by cracks and erosion. Due to the high cost of these blades, welding techniques are being considered to weld/repair worn components, extending their useful lives and delaying the need for expensive replacement components. However, the sensitivities for solidification cracking and post weld heat treatment cracking are relatively high in these alloys. Electron beam (EB) welding can deliver concentrated heat sources and has the potential to address these issues. Numerous welding trials and structural tests must be conducted to identify the optimum method and welding parameters. Weldability is studied over a range of material conditions, welding parameters, and directions. The influence of welding parameters on the fusion zone microstructure and resultant weldability is investigated using combination of microscopic examination and micro-hardness testing. This paper summarizes some of the results of a feasibility study conducted to understand the effects of welding parameters on localized microstructural features, cracking sensitivity, and mechanical properties of autogenously EB welded coupons of single crystal PWA1484.

Jan 1, 2004

By H. J. White

The effect of alloying elements on the mechanical properties and weldability of wrought gamma prime strengthened nickel- base superalloys is well known. An understanding of the basic guidelines concerning alloying additions has led to the invention and development of HAYNES® 282® alloy for applications in aircraft and land base gas turbines and other high-performance high-temperature environments. The alloy combines exceptional high temperature properties with good weldability and fabricability. At high temperatures (~ 900 °C), the alloy is stronger in creep strength than Waspaloy alloy (UNS N07001) and it approaches the creep strength of R-41 alloy (UNS N07041). Because the alloy has better thermal stability, fabricability, and weldability than Waspaloy and R-41 alloys, it is currently being considered as a candidate universal consumable for welding/ repair welding of gamma prime strengthened nickel based superalloys and it is also being considered as a suitable replacement for applications where R- 41, Waspaloy, and 263 (UNS N07263) alloys are currently being used. The alloy was designed to have improved resistance to strain age cracking, a problem common to gamma prime strengthened nickel based superalloys. In this paper, we present (1) results from hot ductility testing of annealed and annealed/aged material; (2) results from Time Resolved X-ray Diffraction (TRXRD) studies during a welding thermal cycle of annealed and annealed/aged material, and (3) gas metal arc (GMA) and gas tungsten arc (GTA) welding of annealed and annealed/aged material.

Jan 1, 2010

By D. Mukerjee, Ramen Datta, Sanak Mishra, R. Veeraraghavan, K. L. Rohira

"Recent efforts at Steel Authority of India Limited (SAIL) has led to the successful development of atmospheric and marine corrosion resistant high tensile Thermo Mechanically Treated (TMT) bars with minimum specified yield strength of 50 kg.mm-2. These rebars are increasingly being used for a wide range of end-applications, namely, concrete reinforcement structures, bridges, flyovers, dams etc. Welding is an important processing tool for each of the above applications. In view of the importance of welding, a comprehensive evaluation of the weldability properties has been carried for the two grades of steels using Submerged Metal Arc Welding (SMAW) process; the most popularly used technique of welding of reinforcement bars (re bars).Implant tests were conducted to assess the cold cracking susceptibility of the steels. The static fatigue limit (SFL) value, determined for the atmospheric corrosion resistant (Cu-TMT) rebars under no preheat and no rebalcing conditions was found to be 63.8 kg mm-2, which was significantly higher than the Minimum Specified Yield Strength (MSYS) (50 kg.mm-2). This indicates adequate resistance to hydrogen induced cracking (HIC). On the other hand, the SFL value obtained for the marine corrosion resistant rebars (Cu-Cr TMT) under no preheat, no rebaking conditions was found to be inconsistent. Repeat of the test with fully rebaked electrodes (350°C-2h) resulted in a high SFL value (60.3 kg mm-2)_The rigidity of the structure or restraint influences the susceptibility of the weld joint to cracking. The cracking tendency increases with restraint intensity (K) of an assembly. The critical restraint intensities determined for the two steels were found to be· in excess of 1680 kg/mm.mm, indicating good welding behaviour with the following welding conditions : for Cu-TMT rebars with no preheat and no rebaking and for Cu-Cr TMT rebars with no preheat and fully baked electrodes; that is under low hydrogen levels."

Jan 1, 1998

By R. K. Hopkins

Fox a great many years fusion welding has been used in and around petroleum refineries, but it is only within six or seven years that the more important pressure vessels have been constructed by this process, because before that time the properties of fusion welds would not withstand such rigorous service. Since the adoption of fusion welding for the construction of this equipment, the refiner has required pressure vessels suitable for operation over a very wide range of conditions. On the one hand, vessels must operate at extremely high temperatures, in the range of 950° to 1000° F., and on the other vessels must be suitable for operation at sub-zero temperatures down as low as -75° F. Also, vessels are required suitable for operation at pressures upwards of 1000 lb. per sq. in., and as low as a 29-in. vacuum. In addition, vessels are required to withstand the attack of very corrosive mediums. It has been a rather difficult task for the fabricator to meet all of these requirements, but as a result of the extensive research carried on by steel manufacturers and several fabricators of class I vessels, practically all of these demands have been met. In order to meet the refiners' requirements for this wide range of conditions, the fabricator has worked closely with the metallurgist. This has enabled him to choose the proper base metal for each service condition, but it has been the fabricator's problem to develop a welding rod and welding technique, as well as a heat-treatment, that would produce in the welded vessel characteristics in and around the weld comparable to those in the base metal. Where corrosion is not a serious problem, and where the operating temperatures are not too high, ordinary carbon steel has served very well. But when corrosion is serious, and/or when the temperatures are either very high or very low, it is necessary to use some form of alloy steel to give satisfactory service.

Jan 1, 1935

By R. K. Hopkins

For a great many years fusion welding has been used in and around petroleum refineries, but it is only within six or seven years that the more important pressure vessels have been constructed by this process, because before that time the properties of fusion welds would not with-stand such rigorous service. Since the adoption of fusion welding for the construction of this equipment, the refiner has required pressure vessels suitable for operation over a very wide range of conditions. On the one hand, vessels must operate at extremely high temperatures, in the range of 950° to 1000° F., and on the other vessels must be suitable for operation at sub-zero temperatures down as low as -75° F. Also, vessels are required suitable for operation at pressures upwards of 1000 lb. per sq. in., and as low as a 29-in. vacuum. In addition, vessels are required to withstand the attack of very corrosive mediums. It has been a rather difficult task for the fabricator to meet all of these require-ments, but as a result of the extensive research carried on by steel manu-facturers and several fabricators of class I vessels, practically all of these demands have been met. In order to meet the refiners' requirements for this wide range of conditions, the fabricator has worked closely with the metallurgist. This has enabled him to choose the proper base metal for each service condition, but it has been the fabricator's problem to develop a welding rod and welding technique, as well as a heat-treatment, that would produce in the welded vessel characteristics in and around the weld comparable to those in the base metal. Where corrosion is not a serious problem, and where the operating temperatures are not too high, ordinary carbon steel has served very well. But when corrosion is serious, and/or when the temperatures are either very high or very low, it is necessary to use some form of alloy steel to give satisfactory service.

Jan 1, 1935

By R. K. Hopkins

For a great many years fusion welding has been used in and around petroleum refineries, but it is only within six or seven years that the more important pressure vessels have been constructed by this process, because before that time the properties of fusion welds would not with-stand such rigorous service. Since the adoption of fusion welding for the construction of this equipment, the refiner has required pressure vessels suitable for operation over a very wide range of conditions. On the one hand, vessels must operate at extremely high temperatures, in the range of 950° to 1000° F., and on the other vessels must be suitable for operation at sub-zero temperatures down as low as -75° F. Also, vessels are required suitable for operation at pressures upwards of 1000 lb. per sq. in., and as low as a 29-in. vacuum. In addition, vessels are required to withstand the attack of very corrosive mediums. It has been a rather difficult task for the fabricator to meet all of these require-ments, but as a result of the extensive research carried on by steel manu-facturers and several fabricators of class I vessels, practically all of these demands have been met. In order to meet the refiners' requirements for this wide range of conditions, the fabricator has worked closely with the metallurgist. This has enabled him to choose the proper base metal for each service condition, but it has been the fabricator's problem to develop a welding rod and welding technique, as well as a heat-treatment, that would produce in the welded vessel characteristics in and around the weld comparable to those in the base metal. Where corrosion is not a serious problem, and where the operating temperatures are not too high, ordinary carbon steel has served very well. But when corrosion is serious, and/or when the temperatures are either very high or very low, it is necessary to use some form of alloy steel to give satisfactory service.

Jan 1, 1935

By H. Thomasson

This paper will deal with on-site maintenance welding using the stick electrode, electric arc process. It is primarily concerned with the underlying principles, the application of which, or the lack of such application, governs the success or failure of the operation. It will discuss first the base metal or item to be welded, including the field identification of its weld-ability and the determination of the procedures to be followed. Second, it will outline heat effects and the interrelation between heat applied as part of a welding operation and heat deliberately applied as part of a heat treating cycle, stressing the fact that in welding the same basic principles are effective. The third consideration will be weld metal and its control of both composition and properties. Last, but not least, distortion, shrinkage and residual stress will be considered and practical means for minimizing their adverse effects outlined.

Jan 1, 1967

By C. R. Whittemore

IT can be truly stated that no branch of the engineering industry has progressed more rapidly in the last few years than that of welding. In spite of depressed economic conditions, this industry has continued to advance along scientific lines, replacing the old hit-and-miss method of welding. The development work is intensive, and increased activity is recorded in every sphere of the industry, new applications of existing methods, together with new processes, being added to those already proved in practice. The general acceptance of the welding processes can be measured by their utilization as a manufacturing tool in the metal-working industries. Many manufacturers have partially or wholly adopted welding. These concerns have on their staffs welding specialists, design engineers, and metallurgists, who are qualified to design and supervise the manufacture of welded parts, at a considerable saving to the purchaser. The steady, consistent, and sound growth of welding is based upon investigation of the fundamentals of the various processes, together with their proper application. The classification of welding processes varies in different countries. In Europe, they are divided into two main classes, namely, heterogenous and autogenous. In the former, the parts are joined, as a ruler without melting the edges, and by using as filler a metal different from that of the object welded. Such welding differs from soldering and brazing in that higher temperatures are required to effect the union of the parts. In autogenous welding, the parts are joined by melting of the edges, with or without the addition of a material similar to the parts being joined.

Jan 1, 1936

By J. G. Price

"The paper reviews state-of-the art welding processes and consumables for structural and pressure equipment applications in offshore environments, particularly the Arctic. Optimum selection of consumables will be discussed with regard to the facility to meet tentative toughness requirements in weldments. Finally, the development of welding procedure specifications will be considered in relation to the prevention of hot or cold cracking and lamellar tearing.Welding RequirementsGeneralThe exploitation of Canadian frontier oil and gas reserves will require a fleet of various types of offshore structures. These will include fixed jacket types and semi-submersibles for the East Coast with huge man-made islands and icebreakers for the Arctic regions. Both these regions will also require supply and drill ships plus subsea pipelines and cargo tankers for transportation. Clearly the welding of these items will plays large part in the over-all integrity and safety of exploration and production operations.The required development in structural steels and pressure vessel steels, for current and future offshore structures, to improve properties, particularly toughness for lower temperature service, has also prompted welding researchers to develop process and consumable combinations to match the parent plate specifications. This development has had to consider particular aspects of weldability such as a low susceptibility to cold cracking and preventing low HAZ toughness. Current research has centred on attempts to increase HAZ toughness with higher heat input welding of newly developed structural steels.The installation of Arctic region pipelines has provided a sound base for future, more complex fabrications in the most severe service temperatures in the Canadian frontier although few of the installations have been designed to the lowest possible exposed temperature of -62°C."

Jan 1, 1987

By H. M. Hobart

THIS paper deals principally with investigations undertaken by the Welding Research Sub-committee of the Welding Committee of the Emergency Fleet Corporation. The general object of the investigations has been to extend the use of welding in the construction of merchant ships and, specifically, to provide a definite basis for obtaining the best economy and efficiency in employing welding in place of riveting in the construction of the hulls of such ships. Composition of Ship-plate Steel The chemical composition of the steel employed in such hull construction varies with the thickness of the plates. Through the courtesy of Mr. H. Jasper Cox of Lloyd's Register of Shipping, the following information may be given concerning the kind of steel plate employed in American Shipyards in 1918 for the hull construction of merchant ships. Lloyd's requirements do not relate to the chemical composition. They require a tensile strength of 58,000 lb. per square inch (40.75 kg. per sq. mm.) for their lower limit and 72,000 lb. per square inch (50.59 kg. per sq. mm.) for their upper limit. For the information of the Committee, Lloyd's obtained from their surveyors at various works data of the carbon content, which is as follows:

Jan 2, 1919

H. G. KNOX,* Norfolk, Va. (written discussion?).-There is one subject that Mr. Hobart seems to have inadvertently omitted from his very valuable paper, and that is corrosion. The shipbuilder, perhaps more than anyone else, has constantly to guard against it, our chief reliance being paint and galvanizing, where practicable. The corrodibility of a welded. joint is salt water must be determined before deciding whether this type of construction is to supersede riveting. At the present time, this question cannot be answered, although considerable work has been started in an attempt to arrive at a conclusion. The British Admiralty and several British shipbuilders have studied it extensively. Their experiments and conclusions have been very carefully followed and reported in this country by Naval Constructor Goodall of the British Navy. To date, these show that no undue fear need be felt from corrosion. At the Norfolk Navy Yard a series of plates welded with various electrodes were submerged in dilute sulfuric acid, such as is used in cleaning prior to galvanizing. While this test may not be conclusive in any quantitative way, it does show a marked difference in the corrodibility of welds made with different electrodes tinder different conditions. To thaw any conclusions from this accelerated this accelerated test would be, however, ill advised. In riveted joints, the exposed heads and points of the rivets always show the greatest tendency to corrode. This is clue to two reasons: first, as they are raised above the surrounding surface the paint is more susceptible to abrasion; and, second, electrolytic action is set up between rivet and plate. These same reasons lead us to expect a tendency of the welded joint to corrode. Various methods have been suggested for decreasing the probable inherent corrodibility of the weld, in addition to the customary coat of paint. These generally embody the introduction of alloys, principally copper; into the electrode material. Plating the electrode with copper is not effective in that the deposited copper segregates in the weld and actually increases the electrolytic action. As far as is known, no extensive test on the so-called copper-bearing alloy steels, which might be made up into electrodes, has been carried out, but when obtainable, electrodes of this alloy will be subjected to service tests.

Jan 6, 1919