Subsea pipeline emergency maintenance refers to the process of cleaning, cutting and performing dry repair underwater to damaged pipelines, or cutting damaged pipeline sections underwater then lifting them to surface for repair, and then placing them back into seabed after repair. Subsea maintenance equipment mainly consists of pipeline recovery tools, cement coating cleaning equipment, pipeline cutting tools.

Cement coating cleaning equipment can clamp subsea pipeline, drive high-pressure water nozzle to move axially and radially along pipeline during maintenance, completing pipeline cement layer and anti-corrosion layer cleaning.