1965年杭州钢铁厂将原来的五吨空气侧吹转炉改建成氧气顶吹转炉,除了氧气吹炼设备及其控制系统外,其余设备和厂房都是利用原有的。行车最大提升能力为30吨。铁水仍由20吨/小时化铁炉供应,每吨钢要消耗100～150公斤焦炭,烧损3％左右的生铁,及消耗25公斤左右的熔剂料,还要占用大片场地和大量人力。因此,如何直接利用高炉铁水供应转炉,就成了迫切需要解决的问题。 In 1965, Hangzhou Iron and Steel Plant converted the original five-ton air-side converter into an oxygen-top converter. Except oxygen blowing equipment and its control system, the other equipment and plants were all made use of original ones. The maximum lifting capacity of 30 tons. The hot metal is still supplied by a 20 t / h iron cooker, consuming 100-150 kg of coke per ton of steel, burning about 3% of pig iron, consuming about 25 kg of flux material, and occupying a large area of ​​workplaces and large manpower. Therefore, how to directly use the blast furnace hot metal to supply converter has become an urgent problem to be solved.