Gallery: Allseas' Giant Vessel Removes Morecambe Bay Platform Topsides

Offshore services firm Allseas said Wednesday it had removed the former DP3 gas production topsides from Spirit Energy’s Morecambe Bay development in the East Irish Sea, using the giant Pioneering Spirit vessel.

This follows the removal of the adjacent DP4 topsides and subsequent transport to the UK in April. 

The two normally unmanned installations used to produce gas as part of Spirit Energy’s complex of eight installations in Morecambe Bay. As the field has matured, the reserves the platforms previously tapped into have been produced by the larger, manned Central Morecambe platform nearby.

"The vessel’s motion-compensated lift technology proved hugely effective in the shallow waters of Morecambe Bay, renowned for strong currents and challenging tidal conditions. For both the DP3 and DP4 operations, it was a matter of hours between arrival in the field and safe execution of the topsides’ lifts," Allseas said.

Pioneering Spirit, dubbed the world's largest offshore construction vessel, will deliver the 5450-tonne DP3 installation to a new disposal and recycling facility at the Fife Energy Park, Scotland, where it will be reunited with the 5400-tonne DP4 structure next week. 

The DP3 topsides on board Pioneering Spirit Allseas’ scope covers engineering, preparation, removal and disposal of two 11,000 tonne normally unmanned installations (NUMIs) and 1000 tonnes of connected subsea infrastructure. 

The latter, including wellheads, pipelines, and umbilicals, was removed by Allseas’ construction support vessel Oceanic in a complicated sequence of approximately 180 lifts. Pioneering Spirit will return to Morecambe Bay to remove the DP3 and DP4 supporting jackets in 2023.

According to Allseas, the DP3 and DP4 topsides removals for Spirit Energy are the vessel’s first heavy-lift assignments outside the North Sea.

"Still a relative newcomer to the offshore heavy lift market, Pioneering Spirit has already installed and removed over 200,000 tonnes of platform weight, moving the work onshore where it is safer and quicker," Allseas said of the vessel which has been in operation since 2016.

"Equipped with motion compensation technology and capable of lifting entire offshore structures up to 48,000 tonnes in just a few hours, Pioneering Spirit spends significantly less time in the field compared to conventional heavy lift barges, which results in drastically reduced emissions footprint," Allseas explained.