Fatigue failure of a Slickline wire induced by corrosion pits

• A Slickline wire was examined in order to assess its causes of failure.
• The fatigue fracture initiated at corrosion pits produced by the operation.
• Normal loading conditions were able to propagate a fatigue crack in the wire.
• The drawing process induced internal cracks that contributed to the failure.

A Slickline wire failed after nearly 400 h of service. In order to find out the main causes and the sequence of this failure, a detailed analysis was carried out on a fracture fragment of this component. This analysis revealed that the operation of the wire produced a series of superficial discontinuities, comprising corrosion pits, fatigue cracking and wear grooves, that provided several stress raisers which served as the initiation point for the failure. Additionally, the manufacturing process introduced some longitudinal cracks that helped in the propagation of the final fracture. Finally, due to the presence of dimples in the last portion of the failure, it could be concluded that the ductility of the material was not compromised.