As operators increasingly opted for subsea field developments in the 1980s, the need to re-enter subsea wells to maintain production rates became more apparent. Operators were buying a completion and workover riser system to re-enter the wells, but they wanted a better and simpler way to carry out interventions, recalls Helix commercial engineering vice president Colin Johnston.
“Riserless came first and then riser-based followed,” says Johnston, whose career in intervention started with coiled tubing well servicing in the North Sea in 1989.
