Analysis of causes of casing elevator fracture

作者:Luo Faqian; Lu Shuanlu*; Li Helin; Qin Changyi; Zhou Jie; Tang Jiping; Chi Jun
来源:Engineering Failure Analysis, 2007, 14(4): 606-613.
DOI:10.1016/j.engfailanal.2006.03.012

摘要

A fracture accident occurred with a 244.5 mm-350 ton casing elevator and a traveling hook during casing running down. This paper gives an investigation of this accident, and analyzes the causes based on fracture surface examination and material tests. Some simulation tests are performed in order to validate the fracture mechanism. It is concluded that the casing elevator fracture originated from quenching cracks caused by surface carburization. Calculations of the fracture load acting on the casing elevator showed that the casing elevator broke first, resulting in hook fracture.