游车大钩断裂原因分析及预防措施

对游车大钩断裂事故进行了调查研究,对其断口形貌进行了宏观和微观分析,发现游车大钩为脆性断裂,断口起源于原始缺陷。对游车大钩使用工况和受力状态进行了分析,认为其断裂位置不在危险截面。对游车大钩的化学成分、机械性能和金相组织进行了全面试验分析,发现游车大钩材质不符合标准要求,且出厂之前存在原始裂纹。依据试验分析结果,最终判定游车大钩断裂主要与游车大钩存在原始缺陷和材料韧性不足有关。为有效地防止类似事故再次发生,建议油田采取预防措施,对钻机提升系统实施驻厂监督,加强钻机系统的到货验收和检查,严格对在用钻机提升系统关键部件定期进行探伤检查和维修。

Failure analysis of traveling block hook fracture and preventative measures

This paper presents an investigation on the fracture accident of traveling block hook.It is found that traveling block hook was brittle fracture and crack originated from original flaw per Macro fractography and micro fractography.It is considered that traveling block hook broke at non-risk section through analysis on its service condition and bear status. It is known that there was original crack in traveling block hook before leaving manufactory and its toughness was poor from chemical composition analysis,mechanical property test,and metallography.It is concluded that traveling block hook broke because of original crack and poor toughness according to the test and analysis results.It is proposed that oil field should take the following preventable measures: supervise for the key drilling and production hoisting equipments during fabricating in manufactory;strengthen check and accept ance for drilling and production hoisting equipments;lnspect and maintenance strictly and periodically for drilling and production hoisting equipment being used.