某高温合金测压导管焊缝漏率超标分析

某高温合金测压导管焊缝漏率超标分析 Analysis of overproof for leakage rate of welding line in high temperature alloy measuring pressure conduit 史春山 SHI Chunshan 1 first-author 郭大治 GUO Dazhi 1 四川航天神坤科技有限公司  2. 四川锅炉高级技工学校  四川航天神坤科技有限公司  2. 四川锅炉高级技工学校  Sichuan Aerospace Sunkun Technology Co.,Ltd. Sichuan Aerospace Sunkun Technology Co.,Ltd. 某高温合金测压导管在氦质谱检漏时发现,其一侧焊缝漏率超标,采用化学成分分析、金相检验、断口分析等方法对漏率超标产生的原因进行了分析。结果表明:由于焊接时导管内部未及时通氩气保护,导致焊缝内表面严重氧化,在进行二次焊接时,焊缝中心外表面形成了热裂纹。导管泄漏主要是由于其焊缝内表面大量氧化物降低了焊缝的强度,以及焊缝外表面曾被打磨,打磨处形成应力集中,在导管液压气密试验和反复装配等作用下,热裂纹发生塑性扩展形成了贯穿壁厚的通道。 A high temperature alloy pressure conduit in helium mass spectrometer leak detection,the side seam leakage rate,by using chemical composition analysis,metallographic examination and fracture analysis method analyzes the causes of leakage rate exceeds bid. The results showed that the inner surface of the weld was seriously oxidized due to the failure of argon gas protection in the tube during welding,and thermal cracks formed on the outer surface of the weld center during the second welding of the weld. The leakage of the catheter was mainly due to the fact that a large number of oxides on the inner surface of the weld reduce the strength of the weld,and the outer surface of the weld had been polished,forming a stress concentration at the grinding place. Under the effect of the hydraulic air-tightness test and repeated assembly of the catheter,the thermal crack developed plastically and formed a passage through the wall thickness. 高温合金 导管 热裂纹 漏率超标 high temperature alloy conduit hot crack overproof of leakage rate TG441.7 2022-03-08 6 50