A Novel Approach to Quantifying the Effect of the Density of Sand Cores on Their Gas Permeability
DOI:
https://doi.org/10.7494/jcme.2022.6.2.33Abstract
The density of moulding mixtures used in the foundry industry plays a significant role since it influences the strength, porosity, and permeability of moulds and cores. The latter is routinely tested in foundries using different solutions to control the properties of the moulding materials that are used to make moulds and cores. In this paper, the gas permeability of sand samples was measured using a custom-made setup to obtain the gas permeability in standard units instead of the usual permeability numbers (PN) with calibrated units. The aim of the work was to explore the effect of density variations in moulding materials on their gas permeabilities. Permeability in this work is quantified in SI units, square metres [m2]. The setup works based on Darcy’s law and the numbers obtained from the measurements can be used to deduce the gas permeability, k, of a sample. Two furan resin bonded mixtures with the same grain size distribution were hand-rammed with varying compaction forces to obtain a variation in density. Cylindrical samples (50 × 50 mm) were prepared using a silica sand aggregate sourced from a Swedish lake. The results of the measurement provided the difference in gas permeability between the samples that have varying densities. The results of permeability were then extrapolated by modifying the viscosity value of the air passed through the sample. In order to find the effect of apparent density variation on the pore characteristics of the samples, mercury intrusion porosimetry (MIP) was also performed. The results were in line with the gas permeability measurements.
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References
Stoll H. (2009). Casting design and performance. Materials Park, OH: ASM International.
Bermudo C., Martín-Béjar S., Trujillo F.J. & Sevilla L. (Eds.). (2019). Use of Additive Manufacturing on Models for Sand Casting Process. Advances on Mechanics, Design Engineering and Manufacturing II, 359–369. Doi: https://doi.org/10.1007/978-3-030-12346-8_35.
Campbell J., Svidró J.T. & Svidró J. (2017). Molding and Casting Processes (190–206). In: https://doi.org/10.31399/asm.hb.v01a.a0006297.
Singh R. (2006). Introduction to basic manufacturing process and workshop technology. New Delhi: New Age International Pvt Ltd Publishers.
Campbell J. (2003). Castings. 2nd Edition. Oxford: Butterworth Heinemann.
Mold & Core Test Handbook. (2001). 3rd Edition. Des Plaines, IL: American Foundry Society.
Ettemeyer F., Lechner P., Hofmann T., Andrä H., Schneider M., Grund D., Volk W. & Günther D. (2020). Digital sand core physics: Predicting physical properties of sand cores by simulations on digital microstructures. International Journal of Solids and Structures, 188–189, 155–168.
Pittman E.D. (1992). Relationship of porosity and permeability to various parameters derived from mercury injection-capillary pressure curves for sandstone. AAPG Bulletin, 76(2), 191–198. Doi: https://doi.org/10.1306/BDFF87A4-1718-11D7-8645000102C1865D.
Dańko R., Dańko J., Burbelko A. & Skrzyński M. (2014). Core Blowing Process – Assessment of Core Sands Properties and Preliminary Model Testing. Archives of Foundry Engineering, 14(1), 25–28.
Dańko R. (2017). Influence of the Matrix Grain Size on the Apparent Density and Bending Strength of Sand Cores. Archives of Foundry Engineering, 17(1), 27–30.
Kashif M., Cao Y., Yuan G., Asif M., Javed K., Mendez J.N., Khan D. & Miruo L. (2019). Pore size distribution, their geometry and connectivity in deeply buried Paleogene Es1 sandstone reservoir, Nanpu Sag, East China. Petroleum Science, 16, 981–1000. Doi: https://doi.org/10.1007/s12182-019-00375-3.
Sundaram D., Svidró J.T., Svidró J. & Diószegi A. (2021). On the Relation between the Gas-Permeability and the Pore Characteristics of Furan Sand. Materials, 14(14), 3803. Doi: http://dx.doi.org/10.3390/ma14143803.
Sundaram D., Svidró J.T., Diószegi A. & Svidró J. (2021). Measurement of Darcian Permeability of foundry sand mixtures. International Journal of Cast Metals Research 34, 97–103. Doi: https://doi.org/10.1080/13640461.2021.1917890.
Winardi L., Littleton H. & Bates C.E. (2005). New Technique for Measuring Permeability of Cores Made from Various Sands, Binders, Additives and Coatings. AFS Transactions, 113, 393–406.
Adams T.C. (1925). Testing Molding Sand to Determine Their Permeability. AFS Transactions, 32, 114–167.
Sutherland W. (1893). The viscosity of gases and molecular force. The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science, 36(223), 507–531.
Darcy H.P.G. (1856). Les Fontaines Publiques de la Ville de Dijon. Paris: Victor Dalmont.
Rouquerol J., Avnir D., Fairbridge C.W., Everett D.H., Haynes J.M., Pernicone N. & Unger K.K. (1994). Recommendations for the characterization of porous solids (Technical Report). Pure and Applied Chemistry, 66(8), 1739–1758.
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Copyright (c) 2022 Dinesh Sundaram, József Tamás Svidró, Judit Svidró, Attila Diószegi
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