Shelf Subsea’s vessel takes break from saturation diving, turns to FPSO scope

Australia-based Shelf Subsea’s DPIII saturation diving vessel Southern Star has started its second project of 2025 following a short layover in Singapore. 

According to Shelf Subsea, the vessel is engaged in a floating production storage and offloading (FPSO) change-out operation in the Gulf of Thailand, where conditions are currently favorable.

“The FPSO change-out scope is a break from Saturation Diving which the Southern has been doing almost continuously for the last 6 months. The work mainly involving ROV intervention using Shelf’s Quasar 21 and Quasar 31, and air diving. Both ROVs are owned and operated by Shelf Subsea,” the company stated.

Southern Star, a 112-meter vessel equipped with a 150 ton active heave-compensated (AHC) crane and Voith Schneider propulsion systems, is considered to be one of the most advanced diving support vessels (DSVs) in the Asia Pacific region. 

The vessel’s design features, including broad beam, roll reduction stabilization tanks, automatic anti-heeling systems, and Voith thruster roll compensation, are said to allow it to maintain stability in challenging conditions.

This latest project follows Shelf Subsea’s recent work in the region with the Oriental Dragon, another DPIII DSV under the company’s charter. The vessel recently completed a single point mooring (SPM) installation in the Gulf of Thailand, marking the first dive from its saturation diving system, according to Shelf Subsea.

“The SPM installation adds to a growing number of successful projects by Shelf Subsea involving activities related to mooring systems – be it Maintenance, Repair, or new installations,” the company said.

In March 2024, Norwegian shipping investment company ADS Maritime Holding acquired a 10% stake in a 2017-built Southern Star.