高压电动截止阀执行机构断裂原因分析

Analysis of Fracture Causes of Actuator of High Pressure Electric Globe Valve

针对XX试验区19#高压电动截止阀执行机构出现脖颈断裂的问题,本文通过宏观断口形貌分析、硬度检测、金相组织检测、有限元模拟等手段进行研究。结果表明:截止阀在开启过程中受较大冲击载荷及震动,长期反复使用加剧了支架内部裂纹的出现,加之变截面圆弧处理不当导致裂纹进一步扩展成为失效的直接原因,但根本原因是灰铸铁材料抗拉强度低导致电动执行机构脖颈失效。根据研究结果对结构进行优化设计,避免执行机构断裂的再次发生,并将结果推广至其他试验区,有效保证试验区整机运行的安全性。

Aiming at the problem of neck fracture of the 19#high-voltage electric globe valve actuator in the XX test area,this paper studies by means of macro fracture morphology analysis,hardness testing,metallographic structure testing,and finite element simulation.The results show that the globe valve is subjected to large shock loads and vibrations during the opening process,and the long-term repeated use aggravates the appearance of internal cracks in the bracket.In addition,the improper treatment of the variable cross-section arc leads to the further expansion of cracks,which is the direct cause of the failure,but the root cause is gray.The low tensile strength of the cast iron material causes the neck of the electric actuator to fail.According to the research results,the structure is optimized to avoid the recurrence of actuator breakage,and the results are extended to other test areas to effectively ensure the safety of the whole machine operation in the test area.