通过宏观分析及材料理化性能分析测试,并结合断面微观分析,对某S135钻杆管体刺穿失效原因进行了分析。结果表明:钻杆刺穿失效的主要原因是热处理工艺不当,使得钻杆外表面形成脱碳层,降低了其力学性能,在钻井过程中复杂的交变应力载荷作用下,钻杆表面腐蚀坑底部首先形成微裂纹并迅速扩展,最终导致钻杆发生早期疲劳失效。 By macroscopical analysis and physical and chemical properties of the test, combined with cross-sectional microscopic analysis of a S135 pipe piercing failure causes were analyzed. The results show that the main reason of drill piercing failure is improper heat treatment process, which causes the decarburization layer to be formed on the outer surface of the drill rod and reduces the mechanical properties. Under the complex alternating stress loads during drilling, the corrosion pit At the bottom, micro-cracks were formed first and then rapidly expanded, leading to early fatigue failure of the drill pipe.