Tunishning ishlashiRefercer Castusiyauzluksiz kasting ishlab chiqarishning silliqligi va manalarning sifati bilan bevosita bog'liq. Tunish vositalaridan foydalanishdan oldin asosiy jarayonning asosiy parametri sifatida pishirish harorati jismoniy va kimyoviy o'zgarishlar, regensiyadagi materiallarning strukturaviy barqarorligi va xizmat ko'rsatish muddati hal qiluvchi rol o'ynaydi. Sovakka chidamli materiallarning turli xil turlari pishirish jarayonida haroratga bo'lgan munosabatida sezilarli farqlarga ega. Pishiruv haroratining oqilona nazorati o'chib ketgan materiallardan foydalanishning asosiy sharti hisoblanadi. Quyidagilar tog 'qatniyotgan materiallarining ishlashi bo'yicha pishirish haroratining asosiy ta'sirini muntazam ravishda tahlil qilish uchun magniy quruq materiallar va magniy püskülülülülüş qoidalari bilan boshlanadi.
1. Magniyni quruq qatnovga chidamli quyruq quyruqlarga ta'siri
1. Kam harorat bosqichi (<200℃): water release and structural stress control The main change of magnesium dry materials in the low temperature baking stage (usually <200℃) is the release of free water and crystal water. If the heating rate is too fast (such as more than 10℃/min), the rapid evaporation of water will form a pressure gradient inside the material, leading to microcracks or even macro cracks. Studies have shown that when the baking temperature is increased at a rate of 5-8℃/min in the range of 100-150℃, moisture can be evenly removed to avoid stress concentration. A steel plant once had a transverse crack in the working lining of magnesium dry material due to excessively fast heating (15℃/min) in the low temperature stage. The crack width reached 3mm and the length was 400-1200mm, which seriously affected the service life of the tundish. In addition, insufficient insulation time in the low temperature stage will cause residual moisture. The residual moisture will evaporate when the subsequent molten steel is poured, and may invade the molten steel to form pores, while weakening the bonding strength of the refractory material. Experimental data show that after 2 hours of insulation at 150℃, the flexural strength of the dry material can reach 7.87MPa, while the strength of the sample that was not fully insulated is only 5.2MPa, a decrease of 34%.
2. O'rtacha harorat sahna (200 -}}}}}}}}} 800 darajadan o'zgarishi va 200-600 darajadagi o'zgarishlar va pasayish suruntekislik va 200-6}} . 200-400 {{}} {{}}} oralig'ida. Bu vaqtda, agar harorat etarlicha uzoq turmasa va qatron to'liq mustahkamlanmagan bo'lsa, o'rta harorat zonasida quruq moddaning kuchi sezilarli darajada kamayadi. Eksperimentlar shuni ko'rsatadiki, 1 soatlik izolatsiyadan keyin quruq moddaning siqilishi 7,9 mpa, masalan, ko va co l₂ kabi siqilgan, masalan, ko va COB kabi gazni chiqaradi va "past" ga kuch sarflaydi. Harorat 800 darajaga yetganda, agar izolyatsiya vaqti etarli bo'lmasa (masalan<2 hours), the gas produced by the decomposition of the residual resin may form pores inside the refractory material, reducing the corrosion resistance. A steel plant optimized the medium temperature stage process (600℃ insulation for 3 hours) to stabilize the medium temperature strength of the dry material at 6.5-7.2MPa, an increase of 30% compared with before optimization.
3. High temperature stage (>800 daraja): Sinterning zichligi va yuqori haroratli chidamlilik darajasi yuqori haroratli pishirish (800-1200 daraja) - bu magniy quruq materiallarni yo'qotish uchun asosiy bosqichdir. Ushbu harorat doirasida magniy zarralari qayta kristallanadi va zich tuzilmani hosil qiladi, bu esa yuqori haroratning yuqori haroratini yaxshilaydi va regress kompleksiyasining yuqori harorati va eroziyasining eroziyasiga chidamliligini sezilarli darajada yaxshilaydi. Tadqiqotlar shuni ko'rsatadiki, pishirish harorati 1100 darajaga ko'tarilganda, quruq haroratning siqilishi 11,3 mlrd. Agar yuqori harorat bosqichiga harorat etarli bo'lmasa (masalan<1000℃) or the insulation time is short (<3 hours), the refractory material is not fully sintered, the internal porosity increases, and the erosion resistance decreases. After a steel plant increased the high temperature baking temperature from 900℃ to 1100℃, the erosion rate of the tundish working lining dropped from 5mm/furnace to 3mm/furnace, and the number of continuous casting furnaces was extended from 10 furnaces to more than 15 furnaces.
2. Magneum pülürray-ning regeum püskürtüksiyasining qatl etilishidagi quyilishlar ta'siri
1. Haroratni bog'lashning kuchayishi uchun haroratning ta'siri: magniy püskürtün qoplamasi püskürtülür, püskürtülülüğü qoplama va doimiy qatlam o'rtasidagi bog'lanishning kuchiga bevosita ta'sir qiladi. Agar harorat past harorat bosqichi bo'lsa (<150℃), the water in the coating evaporates quickly, which will cause hollowing and peeling of the coating; the medium temperature stage (300-600℃) is the key period for dehydration of cement binder hydration products, and improper temperature control will weaken the bonding strength between the coatings. A steel plant adopts a staged heating process (150℃ insulation for 2 hours → 400℃ insulation for 3 hours → 800℃ insulation for 2 hours), so that the bonding strength between the spray coating and the permanent layer reaches 1.2MPa, which is 40% higher than the original process.
2. Yuqori haroratda eroziyalarga chidamliligi to'g'risida yuqori haroratni urishi ta'siri
Magniyning yuqori haroratini (800 {-}}}}}}}}}}}}}} -}}}}} -}}}}} -}}}} {-}}}} -}}}}} {-}} {{{{-}}} Pishiruv harorati 1000 darajaga yetganda, püskürtü qoplamali püskürteyning eroziy chidamliligi indeksi 1,5 dan 2,2 gacha o'sib boradi, bu to'liq inkor etilmagan qoplamadan 47% ga yuqori. Agar yuqori harorat etarli bo'lmasa (<900 daraja), püskürtü chiqaradigan peritlaz kristallar to'liq rivojlanmagan va eroziya qarshiligi sezilarli darajada pasaymaydi. Po'lat zavodi bir marta 5-chi pechni tashlayotganda qisman purkashni qisman purkashga olib keldi.
