Effect of scratching on galvanic corrosion in oil and gas environments

Book · Fri Aug 01 04:00:00 EDT 1997

OSTI ID:504740

Hara, T; Asahi, H ^[1]; Kaneta, H ^[2]

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1. Nippon Steel Corp., Chiba (Japan). Steel Research Lab.
2. Japan National Oil Corp., Chiba (Japan). Petroleum Engineering Lab.

Galvanic corrosion behavior in oil and gas environments when the metal specimens were mechanically scratched was investigated by electrochemical method by using material combinations from carbon steel to duplex stainless steels. Galvanic current and coupled potential increased with mechanical scratching and immediately started to decrease and finally returned to the value before scratching in both sweet and sour environments. Therefore, an increase in galvanic corrosion rate by scratching is negligible small for the long term and localized corrosion due to mechanical scratching does not occur. The change in coupled potential immediately after scratching was small in sweet environments and large in sour environments. It is considered that in case of rapid forming corrosion film of less noble metal, galvanic current after scratching decreased rapidly, however, in case of slow forming corrosion film of less noble side, galvanic current after scratching decreased gradually.

• OSTI ID: 504740
• Report Number(s): CONF-970332--
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
03 NATURAL GAS
36 MATERIALS SCIENCE
CARBON DIOXIDE
CARBON STEELS
DEFECTS
ELECTROCHEMICAL CORROSION
EXPERIMENTAL DATA
HYDROGEN SULFIDES
NATURAL GAS WELLS
OIL WELLS
STAINLESS STEELS
SURFACE PROPERTIES