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Verification of computer simulation in the field of thermal properties of foundry moulds
Šupa, Jan ; Rusín, Karel (referee) ; Cupák, Petr (advisor)
This diploma thesis deals with thermal qualities of moulding mixtures of foundry mould of various types of sand grains and a computer simulation of the solidification of the cast. The aim of this work is to compare the values of thermal qualities of moulding materials bonded with water glass taken in experimental measurements to the values of thermal qualities of moulding materials connected with organic binding agent contained in simulation software. A sample cast will be moulded in order to evaluate cooling capacities of individual moulding mixtures according the shift of thermal axis. These results will consequently be compared to the results of the simulation.
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Binder systems on the base aluminasilicate
Tůmová, Veronika ; Cupák, Petr (referee) ; Rusín, Karel (advisor)
This thesis describes influence of plasticizers and setting accelerators in binder system based aluminasilikates. Following survey includes changes of characteristics of aluminate cements in combination with various setting accelerators. Practical testing and measuring summarizes and compares interdependence of structure, compressive strength, permeability and abrasion resistance. As a final part of thesis individual mixes are analysed economically and are accompanied by suggestions for future use and use in working experience.
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Water soluble foundry binders with heat dehydratation hardening
Šebesta, Pavel ; Rusín, Karel (referee) ; Cupák, Petr (advisor)
Environmental pressure on foundries has forced manufacturers to develop new organic and inorganic binders. One of the options is water soluble binders that can be hardened by dehydration. In addition to tenacity characteristics and regenerability of the forming mixtures another considered aspect is the amount of emissions generated by casting. Use of these new binders does not require expensive modifications of the machines for work with the forming mixtures.
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Optimalization of Technological Properties of Cement Sand Mixtures
Burianová, Klára ; Jelínek, Petr (referee) ; Tegel, Michal (referee) ; Rusín, Karel (advisor)
The work deals with optimization of the technological properties of cement-sand mixtures. The main objective is to find the correct mixture of the individual components which contribute to the rapid solidification of the mixture, hence shorter dismantling. The content is also of a method of measuring and recording during the plasticity of the mixture. Also assessment of the velocity of hydration heat cement mixture in the initial stage of the solidification process in the course of the strength properties of the mixture. To assess these phenomena was used calorimetric method used for measuring hydration heat cement mixture. Further measurements plasticity mixtures and mechanical and physical methods for measuring the compressive strength with the help of a measuring instrument LRU-D.
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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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Systems of self-setting foundry mixtures on the base portland cements
Janíčková, Petra ; Cupák, Petr (referee) ; Rusín, Karel (advisor)
The project elaborated in frame of engineering studies branch N2332-00. The project is submitting design of technology production sand mixture with cement binder – Portland binder CEM I 42,5 N. Pursuant to of the literary pursuit a problem of the sand mixture with cement binder was tested few sand mixture. As optimal composition it turned out application sand mixture with 2 % CaCl2 content and 1 – 2 % Dextrin content. Sand mixture with cement has good moulder and regenerating.
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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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Optimalization of properties of moulding sands in water core of cylinder heads
Hlavsa, Petr ; Malec, Silvestr (referee) ; Rusín, Karel (advisor)
Submitted thesis deals with the change of existing binding system for the Hot–Box method for hardening serving for manufacturing of shell cores the water space of cylinder heads comprise of. Objectives for proposing new binding system for Warm–Box method of hardening under heat are to achieve reduction in creation of condensates and gas substances in binding material compared with existing binding system. Further the thesis is aimed at achieving optimal operating hardness the cores have by reduced batches of binding system and by reduced temperatures of cores in scope reflecting manufacturing conditions in the company Nemak Slovakia s.r.o. While resolving issues there were used methods for evaluating quality of opening materials, core mixtures and cores, further methods for evaluating quality of melt, casts and basic methods for statistical processing of results.
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