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Heat Treatment of Steel Castings
Table of ContentsHeating for QuenchingQuenching ProcessDrawing Operation In an effort to employ cast steel of a stronger structure than that found in the annealed steel castings, the possibilities of heat treatment which will increase the strength without materially decreasing the ductility may be resorted to. The following abstracted report (which is a brief outline of what has already been done by
Round Tables Recovery of Minerals from Fine & Slimes
Table of ContentsGeneral PrinciplesFilm SizingFilm Sizing Appliances in GeneralBuddlesRound Tables in GeneralRound Tables of the Intermittent TypeConvex Round Tables—Intermittent ActionConcave Round Table—Intermittent TypeRound Tables of the Continuous TypeExamples of Round Tables of the Continuous TypeRevolving Tables with Stationary FixturesStationary Tables with Revolving FixturesPrinciple of Operation of the Linkenbach TablePercussion Pound TablesThe Bartsch Round TablePrinciples of Separation of the Bartsch Percussion Round TableRevolving Round
California Gold Dredging
Gold dredging has won an important place in the industry of mining, and it has done so by right of hard-earned merit. Probably no branch of mining has come so prominently to the front in so short a time; by proving its commercial value it has opened to the financier an opportunity for safe and large investments. Ten years ago
Cyanide Destruction Hypochlorite / Chlorine
In the Cyanide Destruction by Hypochlorite reaction, the pH has a strong inverse effect on the ORP. Thus, wastewater treatment facilities must closely control the pH to achieve consistent ORP control, especially if they use hypochlorite as the oxidizing agent. Adding hypochlorite raises the pH, which, if unchecked, lowers the ORP. calling for additional hypochlorite. Controlling the pH at a setting
Fire Clay
Table of ContentsNova ScotiaSaskatchewanBritish ColumbiaConclusions With the rapid development of Canadian industries calling for the use of fire-brick for the lining of furnaces or cement-kilns, for constructing brick-kilns or coke-ovens, for lead-furnaces, etc., the question has often arisen whether the provinces within the Dominion have not the necessary raw materials for the manufacture of such refractory wares. The materials came
Arsenic and Antimony Assay for Electrolytic Copper
Table of ContentsArsenic and Antimony in Converter CopperTitrating solutionsArsenic and Antimony in Refined Copper As the electrolytic plant of this company operates at a current density of approximately 35 to 40 amperes per square foot when running up to capacity, the arsenic and antimony content of the anodes delivered to the plant is of considerable importance as bearing on the
Topographic Maps for Mining Engineer
Few authors of treatises and papers on engineering subjects have given adequate attention to topographic maps. The statement applies especially to mining engineering in all branches. Even those who have discussed such maps have treated the subject only in a general way. Therefore it is proposed to outline in this paper a few of the uncommon yet important relationships which
Timbering Underground Mining Tunnels & Galleries
This paper is not intended to be a technical discussion of square-set framing as used in mines, but merely a short description of the different kinds of framing that have been used in the Butte mines, and what has been decided upon, after years of practical experience, as being the best, taking into consideration the physical condition of the veins
“Wood” Flotation Process & Machine
Table of Contents Molybdenite FlotationCopper Ores In my opinion, the concentration of minerals by flotation is the most interesting problem in ore-dressing, and will command eventually far more consideration than it has at present. For many ores it furnishes a complete method of concentration absolutely independent of specific gravity, and thus simplifies the milling of many difficult combinations. Not having to
Beehive Oven
During the latter half of the nineteenth century and the early years of the twentieth, the major percentage of metallurgical coke produced in the United States came from beehive ovens. It was not until 1893 that the first battery of by-product ovens came into operation (at Syracuse, N. Y.), and only in 1919 did the total production of by-product coke first
Sorting Classifiers
Table of ContentsLaboratory Test on Model Size Three-Pocket UnitThe Adoption of the Constriction PlateThe Classifier in Actual PracticeDesliming ClassifiersTable Feed ClassifiersInner Cone The purpose of this paper is to present a brief sketch of the development of this hindered-settling “sorting” classifier, but primarily to show the actual results obtained in practice with the classifier working on the Butte copper ores at
Vacuum Melting Of Low Alloy Steel
Table of ContentsLaboratory EquipmentExperimental Melting and Casting ProcedureComparison of Air- and Vacuum-Melted SteelNonmetallic InclusionsGas AnalysisComposition Changes During Vacuum MeltingCondensable Metallic VaporsLoss of Alloying ConstituentsConclusions The effect of vacuum melting on the elimination of gases and nonmetallic inclusions for six low-alloy steels was investigated. The purpose of these studies was the analysis and comparison of differences in gas content and inclusions in
High Melting Point Metals Casting Furnace
Table of ContentsDescription of Melting FurnaceMelting Furnace OperationOperation With Specific MetalsMelting & Casting TitaniumZirconium Melting & CastingHafnium Melting & CastingMelting & Casting ColumbiumMelting & Casting MolybdenumCasting Melted TantalumMelting & Casting TungstenMelting & Casting ChromiumMelting & Casting CopperMelting & Casting IronMelting & Casting Metal A laboratory furnace was developed for use in studying the interrelationships among variables associated with skull melting and
How to Save Hole Sludge in Diamond Drilling
Table of ContentsCombination of Core- and Sludge-AnalysesRepresentation of ResultsCross-Sections of Drilling Set the standard sludge box just below the floor of the shanty and in such position that there is room to siphon off the water and take out the sample without moving the box. Connect a tee to the top of the standpipe or casing and lead a pipe
Sampling of Gold Bullion for Quality Control – Elemental Analysis
At the Seventh International Congress of Applied Chemistry I presented a paper, The Assay and Valuation of Gold-Bullion, in which are briefly mentioned a few illustrations of different methods of sampling gold-bullion, particularly cyanide-bars. Since then I have carried on an extensive investigation upon the sampling of gold-bullion in relation to its effects upon the assay-results, in connection with the
Coarse Gold Sampling Method
As run for student class-work the mill contains a feeder, stamps, plate, and vanner. Results in the past indicate that the work of these machines is just as efficient as that of a regular mill handling the same class of ore. It has been the custom to obtain ore principally from Nova Scotia, mainly because it is the nearest source
How to Survey & Sample Diamond Drill Holes
Table of ContentsSurveying in Non-Magnetic FormationsSurveying in Magnetic FormationsDeflections of Drill-HolesDaily ReportsSamples from Drill-Holes Here is a paper on surveying and sampling diamond-drill holes. The present paper gives a more thorough description of these methods, together with a few changes and notes suggested by further experience. Since, the methods, used constantly by the Cleveland-Cliffs Iron Co., have been developed to
How to Make Salt by Solar Evaporation
Table of ContentsSalt Making ProcessesSolar EvaporationMethod of Salt ManufacturingThe Water of Great Salt LakeThe Salt IndustrySalt Making in CaliforniaSalt-Making SeasonStrength of Brine UsedPondsMethods of Pumping BrineHarvesting SaltWaste BitternMilling Salt Making Processes The production of salt in the United States divides itself at the outset into two distinct classes: The mining of rock salt and its purification and separation into marketable
Rolled Steel Roll Shells Manufacturing
Table of ContentsChemical and Physical RequirementsManufactureLife of Shells Without going into an elaborate history of the subject, the following may be mentioned treating on the evolution of roll shells. During the early days of mining-machinery construction, cast iron was used for practically all such grinding devices as those under consideration, usually some good mixture of gray iron being the most
Roll Crushers: Principles, Applications, and Benefits in Mineral Processing | 911 Metallurgist
Table of ContentsRolls for Coarse CrushingRolls for Fine GranulationFrazee RollsRolls for Fine Crushing The art of crushing ores and other materials by means of rolls is a comparatively recent one. While the first record of rolls using iron crushing-surfaces dates back to the year 1806, when they were employed in Cornwall, their principal development has taken place during the past
Reverberatory Smelting
Table of ContentsExperiences With Various FuelsWhat Constitutes Good FuelCharacter of the True CoalPercentage of FinesMoistureAsh and ClinkerDescription and Discussion of Coals UsedOther Important FactorsPreheating the ChargePreheating the AirProducing Steam with Waste Heat In reverberatory smelting, fuel is the chief item of expense, as it commonly is in processes using large percentages of it. Hence the most suitable supply is eagerly
Mine Shaft Sinking Method
Table of ContentsShaft TimberingSinking Equipment and MethodsHandling Shaft WaterRock HandlingMiscellaneous Details The following is not offered as an extended paper on the subject of shaft sinking, but more as a description of the present practice of shaft sinking in the Butte district. The Anaconda company is sinking at present the following shafts: Badger State, Moose, Mountain Consolidated, Mountain View, Pennsylvania and
Mine Bulkheads – Design, Construction & Cost
Table of ContentsDesignConstructionCost While the installation of mine bulkheads to retain water under high pressure is by no means a rarity, the following points which arose in the designing and placing of two of these bulkheads may be of interest: The Hibernia magnetite mine, located about 40 miles west of New York, in the State of New Jersey, is partly