Study on the impact toughness and diffusible hydrogen of G105 drill pipe steel in wet H₂S environment

ABSTRACT

In order to investigate the influence of wet H₂S environment on impact toughness of G105 drill pipe steel, the impact test of drill pipe exposed to NACE A solution for different time was carried out. Meanwhile, the diffusible hydrogen concentration was measured to study the relationship between diffusible hydrogen and impact toughness damage. The results suggest that with the increase of corrosion time, the impact energy of G105 drill pipes decreases from 107.7 to 88.4 J, and the dynamic fracture toughness decreases gradually. The impact toughness damage increases as the diffusion hydrogen concentration increases. However, the impact energy recovery happened after hydrogen releasing. The quasi-cleavage features occur with the increasing of hydrogen concentration.

KEYWORDS:

• G105 drill pipes
• H₂S corrosion
• dynamic fracture toughness
• diffusible hydrogen

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The present work was supported by the Key Laboratory of Ministry of Education of Oil & Gas Equipment (grant number OGE201202-02), Key Projects of Sichuan Provincial Education Department (grant number 15ZA0057) and Key Laboratory of Material of Oil & Gas Sichuan Province Education Department (grant number X151516KCL01).