In order to solve the problem of cracks in ZG270-500 cast steel parts, ZG275-485H cast steel appointed in Chinese Standanrd GB7659-87 is selected as for test.

• 针对实际生产中原ZG270-500铸钢件易出现裂纹的问题,选择GB7659-87《焊接结构用碳素钢铸件》中的ZG275-485H作为试验钢。