406 KB15 KB200020242014Mauder, TomásŠtětina, Josefštevilka:4letnik:48str. 521-524COBISSID:1073578ISSN:1580-2949URN:URN:NBN:SI:doc-USV32DP1enInštitut za kovinske materiale in tehnologijeMateriali in tehnologijecontinuous castingfuzzy optimizationkontinuirano ulivanjemehka optimizacijasecondary coolingsekundarno hlajenjetemperature fieldtemperaturno poljeOptimization of the secondary cooling in a continuous casting process with different slab cross-sections| Optimizacija sekundarnega hlajenja pri kontinuirnem ulivanju slabov z različnimi prerezi|Although the continuous casting of steel began almost 60 years ago, its production still suffers from many serious defects in the final structure. Cracks in the solidifying slab are mainly caused by variable thermal conditions and mechanical stresses. It is well known that the secondary cooling zone has an important effect on the internal and surface quality. Thus, the optimal control of the cooling intensity in secondary cooling is inevitable in order to obtain high-quality products. Nowadays, the control of the slab temperature via numerical temperature-field models is a common practice for controlling the quality of the slabs. This leads to cooling regulation according to the actual casting speed, casting temperature, cross-section of casting slab, chemical composition of steel, etc. Unfortunately, the actual practice in many steelworks is that the cooling regulation is determined as a simple linear function of the casting speed. In order to deal with this problem, the fuzzy-optimization algorithm and numerical model of the temperature field were created. Their combination can provide instructions for how to control the secondary cooling and obtain high-quality of steel. This paper mainly describes the differences between the optimal cooling of different slab cross-sections (width between 800 mm and 1600 mm, thickness between 180 mm and 250 mm). The results show that the proper setting of secondary cooling cannot be done without a consideration of all the main casting factorsČeprav je kontinuirano ulivanje jekla poznano že skoraj 60 let, se v proizvodnji še vedno pojavljajo številne resne napake slabov. Razpoke pri strjevanju slaba so v glavnem posledica spremenljivih toplotnih razmer in mehanskih napetosti. Znano je, da ima sekundarna hladilna cona pomemben učinek na kakovost notranjosti in površine. Zato je za visoko kakovost proizvoda neizogibna optimalna kontrola intenzivnosti sekundarnega hlajenja. Danes se zagotavlja kontrola slabov z uporabo numeričnih modelov temperaturnega polja. To vodi do regulacije ohlajanja, skladno z dejansko hitrostjo ulivanja, temperaturo ulivanja, prereza ulitega slaba, kemijske sestave jekla itd. Da bi obvladali te težave, sta bila postavljena algoritem mehke optimizacije in numerični model temperaturnega polja. Njuna kombinacija lahko da napotke, kako kontrolirati sekundarno hlajenje in zagotoviti veliko kvaliteto jekla. Ta članek opisuje razlike med optimalnim ohlajanjem različnih prerezov slabov (širine med 800 mm in 1600 mm in debeline med 180 mm in 250 mm). Rezultati kažejo, da pravilna nastavitev sekundarnega hlajenja ni mogoča brez upoštevanja glavnih dejavnikov pri ulivanjuTEXTznanstveno časopisjejournalsSlovenian National E-content AggregatorNational and University Library of SloveniaInštitut za kovinske materiale in tehnologije