为了减少氧化物系夹杂生成，通常采用RH、喷粉等二次精炼装置、以及在与大气隔绝情况下出钢、炉渣改质、选择优质耐材等措施，但是这些措施要使钢中全氧低于5pg／g是不可能的，即使钢中全氧为5～7μg／g，则由于氧化物系夹杂也往往能使成品报废。新日铁室兰厂为了消除氧化物夹 In order to reduce the generation of oxide inclusions, secondary refining equipment such as RH, dusting and the like, as well as tapping, slag modification and selection of high-quality refractories in the case of isolation from the atmosphere are generally adopted. However, Below 5 pg / g is impossible. Even if the total oxygen in the steel is 5 to 7 μg / g, the finished product may often be discarded due to the inclusion of the oxide system. Nippon Steel Muroran plant in order to eliminate the oxide folder