汽轮机主油泵泵壳铸件的铸造工艺设计

介绍了汽轮机主油泵泵壳铸件的结构及技术要求,详细阐述了该铸件的铸造工艺,并利用CAD和MAGMA数值模拟软件研究了主油泵泵壳铸件缩孔、缩松缺陷的形成原因和防止措施,最终通过实践验证,形成较为优化的铸件铸造技术方案,得出以下结论:(1)对于类似泵壳结构的中小球墨铸铁件,采取无冒口工艺设计不能完全解决缩孔、缩松缺陷;(2)主油泵泵壳类球墨铸铁件可以采用冒口直接补缩来解决缩孔、缩松缺陷,选用高补缩效率的特种冒口进行直接补缩,可显著地提高铸件质量;(3)对于热节分布复杂的球墨铸铁件,合理匹配使用冒口和冷铁等工艺措施,是形成组织致密铸件的核心技术之一。

Casting Process Design of Steam Turbine Main Oil Pump Shell Castings

The structure and technical requirements of the castings of the main oil pump casing of steam turbine were introduced. The casting process of the casting was described in detail. The formation of shrinkage and porosity of the main oil pump castings were studied by CAD and MAGMA simulation softwwere. Finally,through practice verification,a more optimized casting technical plan was formed,and the following conclusions were drawn:(1)For small and medium-sized nodular iron castings with similar pump casing structure,no rwaser process design could not completely solve shrinkage and shrinkage defects.(2)The main oil pump shell type nodular iron parts could be directly fed by the rwaser to solve the shrinkage and porosity defects. Special rwaser with high feeding efficiency was used for direct feeding,which could significouldtly improve the casting quality.(3)For the nodular iron castings with complex hot section dwastribution,the reasonable matching of the rwaser and cold iron was one of the key technologies for forming dense compact castings.