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Thermoproperties of foundry moulds in dependence on different used foundry sands
Šuráň, Jiří ; Rusín, Karel (referee) ; Cupák, Petr (advisor)
The project elaborated in frame of engineering studies is submitting the study of thermal properties of holding mixtures using different types of sand. Were tested a total of 5 sands: zirkon, ŠH22, chromite, olivine and dunite. Molding compounds were tested for thermal capacity, thermal conductivity and heat accumulation. The highest heat capacity was achieved in dunite sand. The largest heat accumulation had mixture with chromite sand and the best thermal conductivity was found in a mixture with olivine sand.
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Research plasticity of foundry sands
Macků, Martin ; Křístek, Jiří (referee) ; Rusín, Karel (advisor)
The subject of this thesis was to develop a comprehensive methodology for evaluating the plasticity of molding sand. This study was focused on four types of mixtures that are used in the foundry industry. For the evaluation of plasticity was important to provide an indicator of the deformation ability, calculation of deformation and logarithmic transformation for compression. Plasticity methodology was applied in this work only on the pressure effect. Studies of this issue can have a great influence on the production of correct forms due to the ability to withstand tension without breaking form.
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Base sands for manufacture of foundry moulds and cores
Sedláčková, Petra ; Rusín, Karel (referee) ; Cupák, Petr (advisor)
This bachelor thesis describes a summary of sands which are used for foundry molding materials, and includes fields of their utilization. Surface structures of grains as well as their typical chemical and physical parameters are introduced. Czech quartz sands Provodín and Střeleč are described, further also the Slovak sand Šajdíkove Humence, Polish sands Szczakowa a Grudzeń Las, German sands Frechen and Haltern, and the American sand GBM. Out of non-quartz sands, there are listed: chamotte, Molochit, LK Sand from the Sand Team company, ceramic sands CKL and CKI from the Giba company, olivine, dunit (Magnolit), zircon, chromite, magnesite and chrom-magnesite, salt (salt cores). In the summary, there are also listed special sands of the German Hüttenes-Albertus company which are described in detail in Appendix 1. Sands are compared in graphs and tables according to these requirements: thermal expansion, a grain shape and medium grain size, a volume of elutriated parts smaller than 0.9 mm, refractoriness and a point of sintering.
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Water soluble foundry binders with heat hardening
Vaverka, Jiří ; Rusín, Karel (referee) ; Cupák, Petr (advisor)
This thesis is focused on water soluble foundry binders with heat hardening. The thesis comprises general description of moulding mixtures, the description of the most common methods used for heat hardening and primarily the list of current and alternative binders, which reduce negative environmental impact of foundries. Also their qualities, benefits and drawbacks are included.
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Water soluble foundry binders with heat hardening
Dratnal, Lukáš ; Rusín, Karel (referee) ; Cupák, Petr (advisor)
With the increasing foundry requirements we are forced to develop new kinds of foundry binders, either organic or inorganic. There are several requirements for the molding composition and for the proper function. The sand mixture must exhibit appropriate technological, economic and also ecological characteristics. Many environmentally harmful wastes are created from the organic substances contained mainly in binders and catalysts used for molding of the mixture. A good application can be the water-soluble binder cured by heat. These binders allow easy and fast processing and a mixture recoverability.
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Comparison of technological, environmental and economical properties of various binder systems of mould sand mixtures
Ambrož, Ondřej ; Rusín, Karel (referee) ; Cupák, Petr (advisor)
This bachelor thesis is focused on a comparison of technological, environmental and economical properties of various binder systems of mould sand mixtures. The thesis comprises basic overview of the systems used in foundry practice and the individual systems are described properties, advantages, disadvantages and applications. There are mentioned harmful substances which are generated during the preparation of the sand mixture and during casting. Requirements for ecological production castings are a prerequisite for the development of new methods which are environmentally friendly and are also characterized by favorable technological and economic characteristics.
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