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By R. H. Marshall, J. Welchner, E. S. Rowland

This paper presents results on an extension into the realm of high-carbon steels of some work recently published1 on the effects of time at temperature, quenching temperature and prior structure on the hardenability of one 0.20 and four 0.40 per cent carbon alloy steels. It was shown at that time that unless the conditions of time, temperature and prior structure are substantially the same in performing the hardenability test as in conducting hardening of parts in production, the correlation of hardenability information with the hardness and properties of production parts is often not of satisfactory accuracy. The general effects of these variables on the austenitic grain size, distribution of excess carbides and critical cooling rate have been known for many years and one or more have been investigated by Shepherd,2,3 Davenport and Bain,4 Digges,5,6 Digges and Jordan,' Post and associates8 and Roberts and Mehl,9 to mention only a few. There has been no systematic investigation, however, into the quantitative variations produced on the hardenability of commercial high-carbon steels by changes in these factors of time, temperature and prior structure. Procedure A plain carbon hypereutectoid steel, S.A.E. 52100 and Graph-Mo, a molybdenum-bearing high-carbon steel containing some graphite, were chosen for this investigation. The chemical analyses of these electric-furnace steels are given in Table I. The procedure used was exactly that reported previously,' hence the details will not be repeated here. Normalized (165o°F.) and spheroidized prior structures were utilized on all steels with hot-rolled and quenched (I600°F. oil) prior conditions added for the plain carbon steel. The end-quench test developed by Jominy10 was sclected for use in this investigation and, with the noted exceptions, the American Society for Testing Materials standard procedure was followed. The effect of time at temperature was examined at intervals of o, 10 and 40 min. and 4 hr., and a few 16-hr. tests were run. Salt-bath heating of the specimens was employed to control and minimize the

Jan 1, 1944

By H. H. McGregor

Introductory remarks by author When Mr R. C. J. Goode suggested preparation of a paper in the area of manpower utilization in South Africa, I was, while keen to accept his invitation, somewhat hesitant for two reasons. Firstly, I recognized the great difficulty of making a factual contribution, because of the lack of really relevant statistical information available, the fact that much of it is out of date, and the difficulty of researching and co-ordinating it and of evaluating a statistically sound resultant viewpoint. Experience in the actual preparation of this paper has done nothing to change my view in this respect. Secondly, it is obvious that a paper presented to a meeting of this Institute, by a member of it, would be expected to devote considerable attention to the subject in the mining industry. I am not directly employed by the mining industry, although my company has carried out extensive assignments for various sectors of it both in this country and in other parts of the world, since the 1939-45 war. I am more conscious than most of the tremendous technical and managerial skills at the disposal of the industry in this country, and consequently am equally conscious of the hazards of publishing facts and figures which might be taken to indicate any criticism of performance. I am aware that some of the information that I am about to present may indeed generate comment, and possibly even critical comment. I would like to be regarded therefore in presenting this information, as a member of the group, rather than an external critic. Under these circumstances, comment can only be constructive, and this is my earnest hope. The contribution of my paper, if contribution there is, will I hope be in the area of assessing labour productivity in mining, and in secondary industry in such a way that the performance of each against its own past results is comparable. This task has not for the present been to my knowledge attempted, and in advance I wish to take out authors' insurance against legitimate criticism from professional economists and others, by stating that I am well aware of possible short-comings in the arguments. Nevertheless I believe that under the circumstances I have, with the important assistance of several people, been able to take the subject further than has been the case in the past. Finally, I have related productivity in the mining industry and in secondary industry to a target of productivity in the Republic of South Africa. I was fortunate recently in being able to attend a series of lectures by a prominent economist in America. He introduced his subject by calling it 'A broad survey of macro-economics'. Perhaps I might be permitted to describe my paper, in the same idiom, as 'The macro-management of labour'.

Jan 6, 1970

By Samuel Taylor

IF I LIVE another fourteen months and am still con-nected with the coal industry, I shall then have com-pleted a half century with it. Since May, 1874, when .I first entered the bituminous workings as a miner, I think I have held almost every position connected with a mine except possibly that of mule driver, for which I was unfitted by reason of my religious upbringing. We are all agreed, at least I have not heard it contra-dicted, that there is serious over-production in the bituminous industry. This has come about in various ways and is easily explained. During the Fuel Admin-istration, I recall making an estimate of the possible output of the bituminous mines of the country provided they were given a full force of men and a full-car supply; my estimate was a little over a billion tons a year. A few months ago, the late Francis H. Peabody, of Chicago, made a practically identical estimate. If, however, both of these conditions should happen con-currently, there would very soon be no market for the coal, and many of the mines would close down. Even today, if 10 per cent. more cars were furnished, to the bituminous mines, market prices would drop very seriously.

Jan 4, 1923

By N. Theron, R. F. Meeser

The global emphasis on conserving energy resources has led to the adoption of hybrid power systems in vehicles. Optimally applied, hybrid systems can save up to 40% on fuel costs. To optimally manage a hybrid vehicle's energy flow it is necessary to know, in real time, all the energy requirements to complete a given route. The energy consumption depends mainly on the vehicle mass, speed profile, and route topography. Of these, the topographic profile is the one factor that is only route-dependent and not influenced by the vehicle or driving styles. The heading vs. distance profile is also an example of a route characteristic not influenced by the vehicle or driving style. In this study the topographic and heading profiles are used to identify routes, and are easily measured by means of digital barometric pressure and compass sensors. Correlations between the current route and previously travelled/stored routes are performed based on their topographic and heading profiles in a point-by-point manner. Above-ground tests were first performed using a road vehicle and six routes to evaluate the system. The system consistently and correctly identified a 20 km route within the first 4 km. It also proved to function correctly in underground tests through the implementation of an instrumented hand-held surveyor's wheel. This system finds direct practical application in optimizing the energy management of an underground hybrid locomotive used by the mining industry in South Africa, but can also be of benefit in applications where route identification is required and using GPS is not feasible.

Jan 26, 2023

By N. Golchinfar

Tunnels in deep mines are subjected to high stresses. Fracture and failure of the rock mass around an opening can occur when mining-induced stresses are high. In burst-prone grounds, mining-induced seismicity can cause additional dynamic loading which can further increase the stress around the tunnels. When the dynamic stress reaches the rock mass strength, fracturing can occur and rockburst may happen (depending on loading stiffness around the failed rock mass). Rock support installed in the tunnel must be capable of dissipating dynamic energy and holding the failed rocks. Hence, it is important to estimate the depth of failure for rock support design. This paper focuses on how to model depth of failure under dynamic loading. In the modeling, two scenarios of rock failure are considered. In the first scenario, rock failure occurs under static loading and subsequent dynamic loading further increases the depth of failure. In the second scenario, no failure occurs under static loading but in the subsequent dynamic loading, failure around the tunnel is created.

Aug 1, 2013

"What is your history and how did you get involved in mining?Like many SME members, I came from a mining community with a family history in mining, in my case Walkerville, MT. Both of my grandfathers were underground miners. My father was a miner for a short time. He later sold drinks to the miners. Unfathomable by today’s standards, my dad would pick up the miners’ checks at the pay office and have them cashed and waiting with a shot and beer for the miners when their shift ended. My mother was a nurse, who from time to time, would patch up an unfortunate miner. I remember walking past multiple picket lines on the way to and from grade school, watching homes being boarded-up. I grew up with a deep respect for the critical relationship between labor and management.I had no intention of going into mining and initially set out to pursue a career in chemical engineering. But I attended my first two years of engineering at Montana Tech, due to the proximity and affordability. This is where I met Dr. Tom Finch, a mining professor who taught statics to the engineering students. After a coaching session in a hallway, half way through my sophomore year, I switched to mineral processing engineering. In his colorful way, Professor Finch advised me that, “You do not want to make #@*!! erasers and #@*!! Jell-O the rest of your life go talk to the guys in mineral processing.” He was very persuasive and here I am today.How about your involvement with SME?I encountered SME out of school and a little later in my career. Terry Maio and Jim Arnold invited me to local section meetings in the Missouri Lead Belt. That was my first exposure to the technical programming and relationship building that was possible at the local level. After Ozark Lead shut down and I relocated to Nevada, Rich Johnson, Scott Barr and Dave Collins encouraged me to attend my first annual meeting in Salt Lake City, UT. I joined SME at that time and was fortunate to be engaged by members like Art Schweizer and Jim Arnold, and I soon began the leadership progression for the Mineral & Metallurgical Processing Division. Since then, I have supported SME at the national and the local level serving in multiple roles and capacities."

Mar 1, 2017

By M. C. Manderson

The sharp drop in world phosphate demand that took place in 1975 due to temporarily high prices, now seems to be reversing itself. And prices for both phosphate rock and phosphate fertilizers, which declined dramatically from their 1975 highs, now appear to be bottoming out. This recent price weakness has delayed new mining ventures that had been planned for completion by around 1980. While there is ample capacity to supply near-term rock needs, the stage seems to be emerging for a better supply-demand and price environment in the late 1970's and early 1980's.

Jan 1, 1979

L. S. PANYITY.-I made inquiries from the Smith and Dunn people, who are the originators of the compressed air and gas method of increasing the production of oil wells, as to how much pressure the sand will stand; that is, relative to the original rock pressure. They tell me that they have not been able to show, up to date, any pressure in a sand greater than the original pressure. I have also made 'a statement to that effect, but I am really dubious as to whether that is right, as I am not sure that you cannot get a greater pressure. However, I think that a greater pressure would be dangerous because it might cause a loss of gas. C. H. SHAW, ? Lawton, Okla.-In regard to the gas that was put into the pool up in New York State, may it not be possible that, on account of errors, etc., in measuring or computing, there is a mistake in the apparent fact that more gas was gotten out than was put in? L. S. PANYITY.-Unfortunately, I have not the papers I expected from those people to show the actual conditions, but I do not doubt that such

Jan 4, 1919

By Ted Klemetti, Gabriel Esterhuizen, John L. Ellenberger

"Advanced numerical models can be used to evaluate entry support systems in coal mines. However, these methods require specialized software and specialized skills to create the models and evaluate the results. Practicing support design engineers require a method to rapidly assess a proposed support system for a given geotechnical scenario. A prediction equation that can be used to assess roof support systems has been developed from the results of hundreds of FLAC3D analyses that were conducted during recent research. These models were validated against field cases and empirical design approaches and were found to adequately predict entry stability in coal mines. The understanding developed from the model outcomes was used to develop an equation to predict entry roof stability against large roof falls. Least-squares error analysis was conducted to find appropriate parameters for the nonlinear equation. The developed equation can be solved using spreadsheet software, allowing for rapid assessment of alternative support system performance in variable geological conditions. The performance of the prediction equation is evaluated against empirical design methods and against selected case histories of support practices at currently operating mines. Examples are presented that demonstrate the performance of the equation in variable geological settings. The stability factor (SF) prediction equation can be used as an assessment tool to assist in the design of coal mine roof support systems.IntroductionGround falls represent a significant proportion of injuries and fatalities in underground coal mines in the US. During 2013, ground falls were responsible for 4 of the 14 fatalities and 16.6 % of the 1,577 reportable lost-time injuries (MSHA, 2015). In addition, each year about 400 to 500 large roof falls are reported that can extend up to or above the bolted horizon. Large roof falls and associated ground fall hazards can be mitigated through improved support design.The research presented here particularly addresses the problem of large roof falls that extend more than 90 cm (3 ft) above the roof line of an entry and may extend above the bolted horizon. Smaller roof falls that fall out between supports or extend less than 90 cm (3 ft) above the roof line are excluded. These smaller roof falls can be controlled by appropriate surface support such as roof screen or other skin control methods. Also excluded are roof falls that are associated with an individual geological structure such as a slip of fault. Structure-related instabilities can be controlled by strategically locating individual roof bolts or other supports appropriate for the local situation."

Jan 1, 2015

LIST OF MEMBERS, ASSOCIATES AND JUNIOR ASSOCIATES ALPHABETICALLY ARRANGED ||Abad, Leopoldo F, College of Min, Univ of California Berkeley, Cal '23 ||Abarquez, Ramon F, Met, Bureau of Seience Manila, P I '24 ||Abbey, Robert Graham, Student, Case School of Applied Science Cleveland, Ohio '21 Abbort, A N , Mines Supt , Mazapil Copper Co , Ltd Concepcion del Oro, Zacatecas, Mexieo '23 Abbott, Clarence E , Gen'l Supt , Iron Mines Div , Tenn Coal, Iron & R R Co , 1405 Minnesota Ave , Bessemer, Ala '04 Abbott, Louis Benjamin, Chief Engr, Consolidation Coal Co, Elkhorn Div Jenkins, Ky '15 Abbott, Robert R , Met Engr , Peerless Motor Car Co Cleveland, Ohio '12 ||Abbott, Wells Osborn, Ray Consolidated Copper Co Hayden, Ariz '23 Abeel, George H, Jr, Cons Min Engr 4812 W 17th St, Los Angeles, Cal '18 Abel, Albert E, Asst to Pres, Valley Mould & Iron Corpn Sharpsville, Pa '19 Abeloff, Miran S Address Wanted '21 Abernathy, G E, Kansas State Teachers College Pittsburg, Kans '20 Abey, Hiroshi, Min & Met Engr. Takata & Co, 2 Yeirakucho, Niehome, Kolimachi-ku, Tokyo, Japan '17 ||Aborn, Robert H 24 Groveland St, Auburndale, Mass '19 Abouchar, Sylvain Sley, Min Engr & Geol , Care of S H Sekaly, 13 Rue El Nimr, Cario, Egypt '17 Abraham, Arthur W 1828 N Alexandria Ave, Los Angeles, Cal '20 Abrahams, A. I 115 East 82nd St. New York, N Y '14 ||Abrahamson, C. Walter, Min Engr, Brule Min Co Stambaugh, Mich '21 Abrams, Charles Jackson Columbia Bldg, Spokane, Wash '21 Abrams, David H, Min Engr, S E Dickey & Co, 809-11 Johnstown Trust Bldg, Johnstown, Pa '20 Acker, E 01C, Met 128 East Washington Lane, Germantown, Philadelphia, Pa '86 Acker, William L, Diamond Drill Contractor Mears Bldg, Scranton, Pa '18 Ackerman, Ernest R, Pres Lawrenee Portland Cement Co Plainfield, Union Co, N J '15 Adachi, Jinzoo 11 Shiba Park, Shiba-Ku, Tokyo, Japan '88 Adachi, Yuich, Meeh Engr, Anzan Steel Works, Anzan, South Manchuria, China, (Via Dairen) '21

Jan 1, 1923

By B. M. Larsen, T. E. Brower

A perspective is presented of the steel plant sulphur distribution and elimination problem from coal to liquid steel ready for teeming, giving distributions of sulphur over a range of coke sulphur content, and some methods of sulphur control, in the blast furnace, external desulphuriza-tion between blast furnace and open hearth, distribution between fuel, slag, and metal, and methods and limitations of control of sulphur in the open hearth furnace. AS a part of the 1951 AIME symposium on sulphur in steelmaking, it was thought that a discussion of the distribution of sulphur throughout the whole series of operations, from coal and ore to finished steel ingots, might have some value in giving a perspective on the whole problem. The following discussion is an attempt to present such an overall picture. The order is that of the actual plant operations, beginning with a very brief consideration of the coking process. Sulphur in Coal and Coke Since by far the largest source of sulphur entering the steelmaking cycle is in the coal used to make coke for the blast furnace, it would seem reasonable to eliminate some of it, either from the coal, or the coke, or during the coking process. This has appeared impracticable up to the present, at least, for two main reasons: the low activity of the organic sulphur in either coal or coke, and because of price limitations involved in treating a low cost material such as coke. A variable portion, usually M or less, of the sulphur is present in coal in the form of pyrites or similar compounds, and a large part of this sulphur may be removed in the coal washery. Most of the sulphur, however, is normally present as "organic" sulphur, intimately associated with the coal structure. Its distribution prevents any separation by mechanical means. Its low activity makes improbable ' any rapid chemical removal, although hydrogen will remove sulphur from both coal and coke. Thus, prolonged recirculation of coke oven gas in the coking process would tend to leave a smaller percentage of the total sulphur in the coke residue. Table I shows a typical distribution of sulphur from coal into products in the coking process. As the sulphur in the coal increases, the sulphur in the coke tends to increase in about the same proportion. Sulphur in the Blast Furnace The best picture of the situation in the blast furnace is provided by a sulphur balance of raw materials entering, and of products leaving, the furnace. The difficulties in accurate weighing and sampling of the variable solid materials entering this process, and the number of hours required for the raw materials to descend through the furnace under variable operating conditions, make it difficult to obtain an accurate balance. However, balances made over periods of weeks or months tend to average out some of these uncertainties. Table I1 presents three typical sulphur balances similar to a number that the writers have calculated. In most of these the slag volume calculated from the sulphur balance is, in some instances more, and in other instances less, than the value corresponding to the best input and output balances of the other slag constituents (lime, silica, alumina, etc.). Probably the greatest source of error in these calculations is the sulphur content of the slag. Despite some possible inaccuracies the balances of Table II show rather definitely the following points: 1—That 87 to 95 pct of the total sulphur input is in the coke and 95 to 97 pct of the total sulphur output is in the slag. Also, that if any sulphur leaves the furnace with the gas it is relatively small, amounting to a possible 1 pct or less. 2—At the lower sulphur coke level of 0.86 pct the total amount of sulphur charged is 15 Ib of sulphur per ton iron increasing to 26 lb per ton at the higher sulphur, intimately associated with the coal struc-rare burdens containing sulphur-rich ores will the total sulphur burden fail to be nearly proportional to the content in the coke used. 3—The 7 to 9 pct of the total sulphur input from the limestone of furnaces B and C is due to the relatively high sulphur content of the stone, 0.226 and 0.265 pct, respectively. In the case of furnace A, the sulphur content of the limestone was only 0.06 pct which resulted in only 3 pct of the total sulphur input coming from this source. It is rather interesting to compare the sulphur balances of a typical ferromanganese furnace with

Jan 1, 1952

By Tom Barczak

Early in my career, while giving a presentation on shield design for longwall mining at one of the International Conferences on Ground Control in Mining, the late Jim Scott told me that I was finally getting it, because ?I was starting to think like a rock!? Although I didn?t realize it at the time, those few words changed my career forever. At the start of my career, I did a lot of laboratory testing, taking advantage of the unique capabilities of the Mine Roof Simulator to study the performance and design characteristics of longwall shields. I had a pretty good handle on what made shields work and what made them fail, but I was still struggling with how and why they develop their in-service loads and what they were actually controlling as opposed to being passive bystanders in a world beyond their control. It became clear to me that the simplistic models of dead weight loading could not explain the behavior I saw and measured underground. The problem did not go away when I started studying standing support systems. Again, I learned much about the strength, stiffness, and stability of these supports and helped the industry develop several new support products that attempted to provide more efficient support designs. But here, too, the simplistic models of dead weight loading did not seem to fit for me. That?s when I began to incorporate the ground reaction concept as a way of integrating the support response and the ground behavior into a cohesive design methodology. The concept has its limitations, no doubt, but I believe some form of it will be the future of not only designing supports but also, in the broader sense, enhancing the engineering aspects of ground control. The paper presented at the International Conference on Ground Control last year by Esterhuizen (2010) on pillar behavior is evidence of this. Think like a rock. Jim Scott was right. It takes two to dance. You can?t dance alone and you will never understand ground control by thinking like a support! ?Dumb as a box of rocks?? I don?t think so. The answer lies in the rocks!

Jan 1, 2011

By P Lindsay

A numerical model has been developed to simulate the effectiveness and costs of a number of conceptual remedial measures aimed at reducing acidity and metal concentrations in the Ngakawau River and its tributaries near the Stockton Coal Mine, situated on the West Coast of New Zealand. The Stockton Coal Mine has been in operation over the past 100 years. During that time, seepage from waste rock dumps has contributed to elevated acidity and metal concentrations in the Ngakawau River and some of its tributaries. The yearly mean rainfall at the mine site is 6000 mm. The model, developed using GoldSim software, simulates rainfall, run-off and stream discharge for 26 tributaries. It then calculates acidity and metal concentrations in the mine impacted tributaries and the dilution downstream from the mine. The model has been calibrated to measured flow and acidity and metal concentrations in the Ngakawau River and some of its tributaries. Acidity and metal loads are removed from the system in accordance with specified efficiencies and capacities of the respective conceptual remedial measures. The user can compare specific remedial measures, or a combination of conceptual remedial measures. The model predicts the acidity and metal concentrations at a number of monitoring stations for any remedial strategy selected by the user. It also calculates the capital and operational costs for that particular remedial strategy. This paper presents the development of the numerical model and describes how the end-user can use it to compare the efficiency and costs of various remedial strategies by running different æwhat ifÆ scenarios.

Jan 1, 2006

By Charles M. Ryder

In presenting this paper to the Institute I beg to mention, first, the results which I have obtained and the apparatus which I have employed, and to follow this with a brief description of the steps by which I hare perfected this process. My present mode of testing is as follows: I obtain, either from the furnace or from the finished product in any stage in which it may chance to be, a small test-piece, usually about 3/4 of an inch square by 3 1/2 inches in length. I place this test-piece upon the poles of an ordinary electro-magnet, for about one minute, and thus magnetize it to its extreme limit. I then place it upon an indicator (which I will shortly describe), on which indicator there is already placed a piece of steel of similar form which has been magnetized in the same manner, the percentage of carbon of this second piece being definitely known. I then, by means of a scale, which forms part of the indicator, marked in degrees of carbonization, read the exact percentage of carbon contained in the piece under examination. My apparatus consists of an ordinary electro-magnet, connected with a suitable battery of moderate power, by which I magnetize the pieces as before described, and of an indicator which consists of a magnetic needle suitably mounted or suspended, so that it is free to deviate a few degrees only from the zero point, and having a rest, which is used to check the vibrations when in use, and to support its weight when not in use. At a right angle to the natural position of the needle I have a scale about 3 feet long, the zero point of which coincides with the natural position of the needle. This scale is marked in each direction from the zero point in degrees of carbonization. The marking of the scale is in accordance with the following rule: Taking the carbonization of the steel as a basis, I maintain the same proportion between the squares of the distances on the scale as exists between the percentages of carbon in the steel, for instance, if .08 of

By Charles M. Ryder

IN presenting this paper to the Institute I beg to mention, first, the results which I have obtained and the apparatus which I have employed, and to follow this with a brief description of the steps by which I have perfected this process. My present mode of testing is as follows : I obtain, either from the furnace or from the finished product in any stage in which it may chance to be, a small test-piece, usually about 4 of an inch square by 3 1/2 inches in length. I place this test-piece upon the poles of an ordinary electro-magnet, for about one minute, and thus magnetize it to its extreme limit. I then place it upon an indicator (which I will shortly describe), on which indicator there is already placed a piece of steel of similar form which has been magnetized in the same manner, the percentage of carbon of this second piece being definitely known. I then, by means of a scale, which forms part of the indicator, marked in degrees of carbonization, read the exact percentage of carbon contained in the piece under examination. My apparatus consists of an ordinary electro-magnet, connected with a suitable battery of moderate power, by which I magnetize the pieces as before described, and of an indicator which consists of a magnetic needle suitably mounted or suspended, so that it is free to deviate a few degrees only from the zero point, and having a rest, which is used to check the vibrations when in use, and to support its weight when not in use. At a right angle to the natural position of the needle I have a scale about 3 feet long, the zero point of which coincides with the natural position of the needle. This scale is marked in each direction from the zero point in degrees of carbonization. The marking of the scale is in accordance with the following rule: Taking the carbonization of the steel as a basis, I maintain the same proportion between the squares of the distances on the scale as exists between the percentages of carbon in the steel, for instance, if .08 of

Jan 1, 1877

By CHARLES COURT

I must tell you at the outset that I come to this conference deeply disturbed at the 'role of Government in international dealings in mineral and energy resources'. I am disturbed by- the confusion that now passes for policy. I am disturbed by the short- range view of critical problems taken by a majority of Governments. I am equally disturbed by the even shorter range of view taken by a growing army of industries. Many of them clamour for Governments to solve their problems in a specific way, with little regard for any other sector but their own-and with even less regard for the fact that every time a Government takes over some of their responsibilities they surrender some of their freedom. I would not say that longer range views don't exist. But I would say that they don't prevail at the present time. Instead, we are seeing the constant development of many policies for individual problems which don't tackle the fundamental causes. We must get back to basics without delay.

Jan 1, 1978

CONTENTS PAGE BAIN, EDGAR C.-The Nature of Martensite. Discussed by Ancel St. John, Henry S. Rawdon, Jerome Alexander, Howard Scott 1 FEILD, ALEXANDER L.-Effect of Zirconium on Hot-rolling Properties of High-sulfur Steels and the Occurrence of Zirconium Sulfide. Discussed by Beram D. Saklatwalla, Bradley. Stoughton, Andrew M'Cance, George F. Comstock, Alexander L. Feild 12 SAUVEUR, ALBERT and KRIVOBOK, V. N.-Use of Sodium Picrate in Revealing Dendritic Segregation in Iron Alloys. Discussed by George F. Comstock, John H. Hall 17 KINNEY, C. L., JR.-Economic Significance of Metalloids in Basic Pig Iron in Basil Open-hearth Practice. Discussed by V. J. Pazzetti, George B. Waterhouse, C. L. Kinney, Jr 19 NEAD, J. H.-Absorption of Sulfur from Producer Gas in Open-hearth Furnaces.. Discussed by George B. Waterhouse, C. L. Kinney, Jr 26 PRIESTLY, WILLIAM J.-Effect on Steel of Variations in Rate of Cooling in Ingot Molds. Discussed by Emil Gathmann, Paul E. McKinney, George A. Dornin. 27 MONYPENNY, JOHN H. G.-Stainless Steel, with Particular Reference to the Milder Varieties (Stainless Iron). Discussed by P. A. E.-Armstrong, Beram D. Saklatwalla 33 ROYSTER, P. H., and JOSEPH, T. L.-Effect of Coke Combustibility on Stock Descent in Blast Furnaces. Discussed by Ralph H. Sweetser,. Richard Franchot, Sidney Cornell, T. L. Joseph 41 DAVIS, F. W., and BOLE, G. A.-Observations on Requirements of Refractories for Open Hearth. Discussed by C. L. Kinney, Jr., L. F. Reinartz, P. E. McKinney 46

Jan 5, 1924

By Connor Langford, Murray Gant, Ken Massé

For public organizations, preparing accurate project cost estimates is a critical component in capital project planning. Project delivery methods provide a structured approach to moving projects through the design and construction lifecycle, and typically use cost estimates as key inputs at each stage to determine if the project will advance. As design stages can occur years or even decades before construction contracts are awarded, estimates need to make reasonable assumptions about how the work may be executed (means and methods) as well as potential future market trends so that appropriate values for material pricing, labour costs, escalation, and owner’s costs can be included. This process is challenging enough during stable markets, as historic trends can often be misleading and require a suitable understanding of economic factors to use appropriately. When you mix in the market volatility that has been observed since 2020, developing accurate project cost estimates becomes even more challenging. In cases such as this, having a structured approach to cost estimating that includes an adequate risk-based reserves cannot be overstated as it provides the basis for ongoing project decisions. This paper explores some of the historic and more recent market trends that have impacted key aspects of project cost estimates for capital project planning. It also provides recommendations on how to develop cost estimates for infrastructure projects, with examples from Metro Vancouver, which plans for and delivers regional-scale services to 2.6 million residents. A brief commentary on the use of escalation clauses in contracts is also presented.

Jun 13, 2023

The Fourth Session of the Forty-Sixth Meeting of the Rocky Mountain Coal Mining Institute convened at the Hotel Colorado, Glenwood Springs, Colorado, June 21, 1950, at 9:30 a. m., G., E. Sorenson, President, presiding. PRESIDENT SORENSON: The meeting will conic to order, please. Gentlemen, we have quite a program this morning, so we had better push this thing along. Be fore we start this morning, I would like to ask Mr. Davis if he wouldn't come up and say a word or two for us. He is the editor of Coal Age. Mr. Davis. MR. DAVIS: This is quite an unexpected honor. I didn't know that I would be called on to speak to you. It will be brief, but very sincere. I have enjoyed every minute of my stay here with you people in the west. It is my first visit out this way, and I have enjoyed every minute of it. I have two more weeks to go out here, and I will probably see a lot of you in your own back yards.

Jan 1, 1950

I must tell you at the outset that I come to this conference deeply disturbed at the `role of Government in international dealings in mineral and energy resources'. I am disturbed by the confusion that now passes for policy. I am disturbed by the short- range view of critical problems taken by a majority of Governments. I am equally disturbed by the even shorter range of view taken by a growing army of industries. Many of them clamour for Governments to solve their problems in a specific way, with little regard for any other sector but their own-and with even less regard for the fact that every time a Government takes over some of their responsibilities they surrender some of their freedom. I would not say that longer range views don't exist. But I would say that they don't prevail at the present time. Instead, we are seeing the con- stant development of many policies for individual problems which don't tackle the fundamental causes. We must get back to basics without delay.

Jan 1, 1978