純氧頂吹轉爐煉鋼法
這種方法是1952年以后發展起來的新技術，它是目前世界上采用較多也是較先進的一種方法。純氧頂吹轉爐煉鋼有以下優點：
1、生產速度快 由于用純氧吹煉，就會高速降碳，快速提溫，大大縮短冶煉時間。一座300t轉爐吹煉時間不到20min，包括輔助工作時間在內，一共不超過1h。
2、品種多、質量好純氧頂吹轉爐既能煉普通鋼，也能煉普通低碳鋼。如首都鋼廠采用這種方法成功地試煉了一百多種鋼材。由于用純氧吹煉，鋼中氮、氫等有害氣體含量較低。
3、基建投資和生產費用低 純氧頂吹轉爐的基建投資相當于同樣生產量的平爐車間的60～70％，生產費用也低于平爐。
目前純氧頂吹轉爐隨著氧槍的多孔噴頭的研制成功，大大提高了單位時間內的供氧量，并由于操作技術上的革新（例如，用電子計算技術來調節、控制冶煉過程），不論轉爐容量的大小，吹煉時間基本上相差不多，即使300t轉爐，凈吹氧時時也可縮短到12min左右。在一定限度內，爐容量越大，經濟效果越好，因此頂吹轉爐迅速走向大型化。現在世界上最大的轉爐為350t，并且正在研究建造400～450t轉爐。
Basic oxygen steelmaking (BOS, BOF, Linz-Donawitz-Verfahren, LD-converter) is a method of primary steelmaking in which carbon-rich molten pig iron is made into steel. The LD-converter is named after the Austrian placenames Linz and Donawitz (a district of Leoben). The vast majority of steel manufactured in the world is produced using the basic oxygen furnace. Modern furnaces will take a charge of iron of up to 350 tons and convert it into steel in less than 40 minutes. The LD converter is a refined version of the Bessemer converter where blowing of air is replaced with blowing oxygen.
Blowing oxygen through molten pig iron lowers the carbon content of the alloy and changes it into low-carbon steel.
The process is known as basic due to the pH of the refractories - calcium oxide and magnesium oxide - that line the vessel to withstand the high temperature of molten metal.
Basic oxygen steelmaking (BOS, BOF, Linz-Donawitz-Verfahren, LD-converter) is a method of primary steelmaking in which carbon-rich molten pig iron is made into steel. The LD-converter is named after the Austrian placenames Linz and Donawitz (a district of Leoben). The vast majority of steel manufactured in the world is produced using the basic oxygen furnace. Modern furnaces will take a charge of iron of up to 350 tons and convert it into steel in less than 40 minutes. The LD converter is a refined version of the Bessemer converter where blowing of air is replaced with blowing oxygen.
Blowing oxygen through molten pig iron lowers the carbon content of the alloy and changes it into low-carbon steel.
The process is known as basic due to the pH of the refractories - calcium oxide and magnesium oxide - that line the vessel to withstand the high temperature of molten metal.
History
The first basic oxygen steelmaking process was the LD process developed in 1952 by voestalpine AG in Linz, Austria.[2] Some major steelmaking companies in the US did not convert to this process for some years, with the last Bessemer converter still operating commercially until 1968. The LD process replaced both the previously common Siemens-Martin process, also known as the open-hearth process, and the Bessemer process. European companies replaced open hearth furnaces with BOF rapidly after WWII, but US companies were reluctant to give up the old and tried open hearths. The first company in the U.S. to use this type of furnace was McLouth Steel in Trenton, Michigan.
The first BOF in North America was installed at Dofasco in Hamilton, Ontario, Canada.
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