某S135钻杆管体断裂失效分析

针对某S135钻杆断裂事件，对失效样品进行了宏观检验、理化性能测试及断口分析。结果显示，失效样品内外表面均被腐蚀，腐蚀坑内有较多裂纹，理化性能符合标准要求。分析表明，钻杆断裂是交变应力和腐蚀介质共同作用的结果，腐蚀坑的提前形成大大缩短了钻杆的使用寿命。建议钻杆下井使用后要彻底清洗，加强存储期间的防护，并在使用前进行无损检测，防止失效事故发生。

Fracture Failure Analysis of S135 Drill Pipe

Aiming at the fracture event of S135 drill pipe, the macro inspection, physical and chemical properties inspection and fracture analysis of the failed sample are carried out. The results show that the physical and chemical properties meet the standard requirements. The internal and external surfaces of the failed sample have been corroded, and many cracks are found in the corrosion pit. The analysis shows that the fracture of the drill pipe is the result of the joint action of alternating stress and corrosion medium. The formation of the corrosion pit in advance greatly shortens the service life of the drill pipe. It is suggested that the drill pipe should be thoroughly cleaned after being used in the well, protected during storage and carried out NDT before use, so as to prevent failure accidents.