Failure analysis of hydrofracturing tieback string and improvement proposals

Hydrofracturing tieback is easy to produce yield failure due to various loads and complex forces. This paper analyzes the deformation causes of the tieback string during fracturing of well A in Dongsheng gas field. Through ANSYS finite element software analysis, it is clear that the reason of deformation of the pipe column is caused by the stress exceeding its yield strength limit. The analysis shows that increasing the selfstrength of the tieback string and applying the annulus equilibrium pressure during fracturing can effectively reduce the damage risk of the tieback string, and puts forward some improvement proposals.