美国铸造工作者协会所属的铁水球化处理委员会,于1978年对美国所有生产球墨铸铁的铸造厂进行了调查。R.A.加里逊等人报导了这次调查所取得富有启发性的结果。填写调查表的制造厂,占美国生产球铁工厂总数的63%。有68%的球墨铸铁是用冲天炉生产的。但是,每周产量低于100吨的小型铸造厂,用冲天炉生产球铁的只占32％,其余68%是用电炉生产的。值得注意的是,与1957年所进行的调查相比,通过相应的炉料调整,原铁水含硫量已 In 1978, the United States Foundry Workers Association’s Iron Ball Water Treatment Committee investigated all foundries in the United States producing ductile iron. R.A. Garrison et al. Reported on the inspiring results of the survey. Fills in the questionnaire factory, accounted for 63% of the total number of ductile iron factories in the United States. 68% of ductile iron is produced using cupola. However, small foundries that produce less than 100 tons per week use only 32% of the ductile iron to produce ductile iron and the remaining 68% are produced in electric furnaces. It is noteworthy that, compared with the survey conducted in 1957, through the corresponding charge adjustment, the original hot metal has sulfur content