一般中小厂生产大型的铜铸件,由于没有大容量的反射炉,而坩埚炉或感应炉容量又有限,因此难以实现。我厂自1963年开始生产连续铸管以来,因生产需要,同时生产重达100～750公斤的低锡青铜外结晶器(如图1所示)。根据低锡青铜含锡量(<2％)和锌量(<1.2％)低的特点,采用三节炉熔化,炉外浇包内添加 Small and medium-sized factories generally produce large copper castings, because there is no large-capacity reflex furnace, and crucible furnace or induction furnace capacity is limited, so difficult to achieve. Since 1963, our factory has been producing continuous cast pipes, due to the need of production, we also produce low tin bronze outside mold weighing 100 ~ 750kg (as shown in Figure 1). According to the low tin content of bronze (<2%) and the low amount of zinc (<1.2%), the furnace is melted in three stages,