The Platts hardness factor of coal seam is less than 1 (f < 1), and the structure is simple. The inclination angle is between 27° and 55°, with an average of 45°. ... a 13 are polynomial coefficients, constants, as shown in Table 3. Table 3 Polynomial coefficient values of coal face displacement prediction model. Full size table.
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where μ s is the coefficient of static friction and μ k is the coefficient of kinetic friction. The value of μ s is generally higher than the value of μ k for a given combination of materials.. Coefficients of friction between materials are best determined through testing. However, it is possible to find tables in the literature for friction coefficients between …
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In the study by Sachpazis (1990), equations with high correlation coefficients between the USC and the SHH for the calcium carbonate rocks were determined. ... Hardness is an empirical test used to identify and classify materials and therefore the hardness value of rock varies according to the applied hardness method. …
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LNG. View our key LNG price assessment Platts JKM™ for spot physical cargoes delivered ex-ship into Japan and South Korea (with normalized prices for spot cargoes to China and Taiwan also included) alongside JKM™ swaps. Access daily LNG spot market assessments: delivered ex-ship prices for Northwest (NWE) and Mediterranean (MED), …
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Vickers Hardness Sensitivity Coefficients ISO 6507-1 defines the Vickers hardness value, HV, as: 2 2 2 sin 0.102 d F HV = × α where: F = force (in N) α = plane angle of the indenter (136°) d = mean indentation diagonal length (in mm) Partial derivatives allow the sensitivity coefficients for force, indenter angle, and indentation diagonal
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The characteristics of the selected substrate include high porosity and permeability coefficient, stable chemical properties, strong decontamination ability, etc., …
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Iron ore is one of the most important mineral resources supporting national economy development,whether we can make economical ues of it,which is in relation to the healthy development of steel industry and industry security.But with the mass exploiting of iron ore,the iron ore with the high grade and easy to separate have became scarcity,so ...
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The Platts hardness factor of coal seam is less than 1 (f < 1), and the structure is simple. The inclination angle is between 27° and 55°, with an average of 45°. …
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With an inclined width of 195 m and a mining depth of 1000 m, with the working face had an inclination angle of 3 to 10 and the Platts hardness coefficient of …
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Different rocks have different hardness indexes and drillability are also different. Ruggedness is often used to indicate how easy it is to break a rock. The size of the firmness is expressed by the firmness coefficient. The firmness coefficient is also called the hardness coefficient, which is also called the Platts hardness coefficient f value.
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In addition to the API key, some Platts API datasets may require an access token to be included in every API request. This token can be generated using y... Sat, 19 Aug, 2023 at 7:11 AM. How do I get access to Platts API? In order to get access, you first need to get accredited into our system for the data you are interested in. ...
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Ore Hardness Grade δ Pressure (kg/cm 2) Platts Hardness Coefficient Crushability Coefficient Grindability Coefficient Examples; Very Soft <200 <2: 1.3-1.4: 2.00: Gypsum Stone Slate: Soft: 200-800: 2-8: 1.15-1.25: 1.50: Limestone: ... Crushability Coefficient Formula: Grindability Coefficient Formula:
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Material 4140 coefficients of linear thermal expansion: Temperature, °C (°F) Value (10-6 /K) Treatment or condition: 20-100 (68-212) 12.2: Oil hardened, tempered: 20-200 (68-392) 12.6: ... and the corresponding Rockwell hardness can be obtained. Forging. Material 4140 forging temperature is about 1232 °C (2250 °F).
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The experimental values of compressive strength of argillaceous sandstone and sandy mudstone are 20~42 MPa, platts hardness coefficient f = 3.2, and the roof …
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1, the mining object high hardness (Platts hardness coefficient =16 18), the material block degree (weight>500 kgaccounted for 30%), the Qing (eating) foundation work, this is the worst condition. As in Lianyungangportconstruction, mining rock are gneissic granite, bucket teeth service life is very short, only 8 – 12 days.
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The flushing effect also will be very low when the Platts coefficient of coal near the flushing hole is very high. ... Generally, coal with high hardness is commonly considered to be a non-outburst risk; however, several coal mines with hard coal seams in China have experienced coal and gas outbursts. Coals with different degrees of ...
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Numerical analysis of influencing factors of steeply inclined coal . The Platts hardness factor of coal seam is less than 1 (f < 1), and the structure is simple The inclination angle is between 27° and 55°, with an average of 45° Table 3 Polynomial coefficient values of coal face ZrB2/Mo multilayers were prepared by the magnetron sputtering technique on Si …
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The results show that there is a "concave" quadratic relationship between the filling step and the maximum displacement of the floor, and there is a "convex" quadratic relationship …
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Coefficient of thermal expansion, 10-6 /K (μin./in. ·°F) 12.3 at 20-100 ℃ (68-212 °F) Oil hardened, tempered 600 °C (1110 °F) ... The high hardness of 4340 alloy steel requires that the material be welded in the annealed or tempered state and then heat treated to resist martensite formation and cold cracking. However, as in motor shaft ...
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The hardness of the ore is expressed by the compressive strength of the ore or the Platts hardness coefficient (The compressive strength divided by 100 is …
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The texture coefficient, Vickers hardness, and Schmidt hammer rebound number were tested and assigned to each rock type. After that, a set of laboratory drilling tests were carried out on each sample using a new test rig developed for this purpose. As a standard method for vibration analysis, the "root mean square (RMS)" value was applied ...
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The Platts hardness coefficient and permeability of the coal seams are in the range of 0.2–0.8 and 4 × 10 − 4 –1 × 10 −3 mD, respectively. The gas content is between 10 and 22 m 3 /t, and the gas pressure can reach 6.0 MPa.
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1, the mining object high hardness (Platts hardness coefficient =16 18), the material block degree (weight>500 kgaccounted for 30%), the Qing (eating) foundation work, this is the worst condition. As in Lianyungangportconstruction, mining rock are gneissic granite, bucket teeth service life is very short, only 8 – 12 days.
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Platts therefore no longer specifies the Conradson Carbon Residue (CCR) measurement used in some of Platt's fuel oil assessments in order to remain consistent with the ISO 8217:2010 standard. The two measuring bases express the results of two different, but
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By size Platts hardness coefficient can be divided into five ore hardness level> Platts hardness grade ore ore hardness coefficient is very soft, for example <2 bituminous coal, lignite, water quenched slag, ash, clay, mix 2-4 soft limestone, shale, clayey sandstone, slag, coal gangue 4-8 in a hard limestone, gypsum, quartz sandstones, fluorite ...
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applies to drilling or breaking rock with a high Platts hardness coefficient. Background In 2015, the BP Statistical Yearbook of World Energy pointed out that China is still the world's largest energy consumer, which accounts for 23% of global consumption and 61% of global net growth. Coal resource consumption accounts for 66.03% of total ...
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Coefficient of friction Compression set after 24 hr at 175C % Compressive modulus GPa Compressive strength MPa Elongation at break % Hardness - Rockwell Izod impact strengt h J m-1 Poisson's ratio Tear strength N mm-1 Tensile modulus GPa Tensile strength MPa Cellulose Acetate Butyrate CAB - - - - - 60 99 260 - - 0.3-2.0 20-60 Ethylene-
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Hardness and thickness are important dimensions of plating materials because the effectiveness, longevity, and cost of the final product depend, not only on the …
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The coal seam floor is mostly soft IIIb, and the stability of coal seam roof and floor is not good; the hardness of the top and bottom of the main coal seams is quite different, most of the Platts coefficient is less than 6, and the excavation is good, which is suitable for large-scale and mechanized mining. ">
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Olivier Lamarche 1, James A Platts, Anne Hersey. Affiliation 1 Department of Chemistry, Cardiff University, P.O. Box 912, Cardiff CF10 3TB, Wales, U.K. PMID: 15154749 ... and hydrogen bond acidity and basicity descriptors are validated for their ability to predict the various partition coefficients of 80 challenging molecules. As well as this ...
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A technology of mechanical properties and ore, used in the application of stable shear force to test the strength of materials, grain processing, testing the hardness of materials, etc. Pulverization and other problems, to achieve the effect of reducing the content of particle size, reasonable composition, and increasing the content of the intermediate easily …
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In most cases, opting for T5 heat treatment or T6 heat treatment will only increase the hardness of A356 aluminum alloy. Under normal circumstances, T6 heat treatment will increase the hardness of A356 aluminum alloy by 12 to 15 Webster hardness. Of course, it will also improve other mechanical properties for better die casting results. ...
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In the test, the hard granite, a kind of solid and compact rock with the Platts hardness coefficient of 15–17, was selected as the grinding material. The mass loss of …
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Since the coefficient of hardness mainly reflects only fracturing under compressive loads, and in real conditions tensile and shearing forces are often used, it becomes necessary to introduce ...
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With advantages such as concise and compact structure, safe and reliable, short auxiliary time, flexible response, operate and maintain simple and convenient etc. Drilling rock in ideal drilling speed among Platts hardness coefficient f=6~15. 3.
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Platts is constantly reevaluating this model, discussing industry feedback and trends to make the Platts Analytics Yields and Netbacks valuations more accurate. Where Platts Analytics Yields and Netbacks can be found Platts Analytics Yields and Netbacks calculations are produced every day for all locations. They are available through several
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DOI: 10.1016/J.JAFREARSCI.2015.01.005 Corpus ID: 129311365; Correlation between Schmidt hardness and coefficient of restitution of rocks @article{Ansari2015CorrelationBS, title={Correlation between Schmidt hardness and coefficient of restitution of rocks}, author={M. K. Ansari and M S Ahmad and Rajesh …
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The global Iron Ore specifications guide contains the primary specifications and methodologies for Platts Iron Ore global catalogue of price assessments. The various sections of this guide are designed to give S&P Global Commodity Insights subscribers as much detail as possible about a wide range of methodology and specification issues.
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The hardness is low (Platts hardness: 1– 3), and the particles are fragile. The hydraulic permeability coefficient is relatively small: 1 × 10 −13 – 2 × 10 −9: ... The characteristics of the selected substrate include high porosity and permeability coefficient, stable chemical properties, strong decontamination ability, etc., which ...
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