This paper mainly discusses forming mechanism of casting blowholes , introduces several inspecting methods briefly and puts forward prevention measures.

着重论述了气孔的形成机理。简要地介绍了几种检验气孔的方法，还从四方面提出气孔的防止措施。

Results indicate that the defects arise from the non-conformance of the protective flux to specified requirements in physical properties, which incurs blowholes at the subsurface of the steel plate.

分析结果表明，这种表面缺陷是由复合保护渣物理性能不合格而引起的皮下气泡。