Abstract: As the crude oil transportation channel of offshore platform,the mixed transportation submarine pipeline may not be able to operate under safe working conditions due to corrosion and external damage during production. When the degree of corrosion reaches a certain limit,a new submarine pipeline needs to be replaced. In the process of replacing two mixed transportation submarine pipelines on an offshore platform due to corrosion defects,in order to solve the problems of long shutdown time and impact on output,the temporary production scheme of water injection submarine pipeline was adopted. The temporary production of WHPX and WHPY platforms was realized through on-site process transformation after assessing the temporary mixed transportation capacity of water injection submarine pipeline,analyzing the risk of temporary production resumption and designing the instrument control scheme.

Key words: water injection pipeline reflux, transportation capacity, process transformation