| Damage to submarine pipeline has been the most significant problem that disturbs on-sea oil exploitation in development of submarine line. In-time repair for various damages of submarine pipeline is of great significance to ensure oil/gas production on sea. The paper mainly studies the galvanic corrosion which aroused by two different metals joined in seawater when we repair the damaged submarine pipeline temporarily. In order to find out the rules of galvanic corrosion'change in marine, galvanic corrosion scope and its intensity, we process a particular experiment research on galvanic corrosion which formed by brass and pipeline steels in laboratory and on-site.We make several experiments in laboratory. Firstly, in order to be familiar with the waters'condition of Chengdao, we make several tests on the temperature, oxygen content, salinity, pH value, suspended solids and corrosive behavior of seawater which is fetched in different season and different depth of the sea. Then we make research on the galvanic corrosion of three pipeline steels X52, X56, ang16Mn in seawater; test their changing rule according to different velocity, temperature, time and area ratio. Therefore, we can conclude the primary factors which influence the reliability of the temporary repairing technology through analyzing the above rules. Finally, we measure the circuit potential, the potential distribution and the probability of reversion of cathode/anode which formed by brass and 16Mn in order to make sure the galvanic corrosion scope and its intensity in seawater. We also negated the probability of reversion of cathode/anode through this study.When we processed the experiment in the ocean, a section of pipeline which imitates the temporary repairing technology was designed for the experiment. Through this experiment, we profoundly understand the galvanic corrosion in the ocean, and finally evaluated the reliability of the temporary repairing technology.
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