超超临界汽轮机大型铸件加工工艺及质量控制

Machining Technology and Quality Control of Large Castings for Ultra-supercritical Steam Turbine

高中压汽缸、蒸汽阀门是超超临界汽轮机组重要的高温铸件,该类件制造和运行过程中均易出现裂纹、缩孔、夹渣缺陷。为了保证机组的安全运行,重要铸件须选择合理的材料并采用合适的加工工艺。本文研究了高温铸件的加工、检验工艺流程。通过对铸件典型质量事件分析,阐述了大型铸件缺陷的基本分析和处理流程。提出了铸件质量检验的主要措施。

High/medium pressure cylinder and steam valve are important high temperature castings for ultra supercritical steam turbine. Cracks, shrinkage holes and slag inclusion are easy to appear during manufacturing and operation of the parts.In order to ensure the safe operation of the unit, the important castings must select reasonable materials and adopt appropriate processing technology. The processing and inspection process of high temperature castings were studied. Based on the analysis of typical quality events of the castings, the basic analysis and treatment flow of defects in large castings were described. The main measures for the quality inspection of the castings were put forward.