Decom North Sea

Picture1
Back to Directory

Company Overview

Allseas Group S.A. is a world-leading contractor in offshore pipeline installation, heavy lift and subsea construction. 


Our approach is to support clients already in the conceptual design stage, and offer services for project management, engineering and procurement up to and including installation and commissioning.

Allseas owns and operates a state-of-the-art fleet of specialised heavy-lift, pipelay and subsea installation vessels designed and built in-house. The latest addition to our fleet, the 382 m long, 124 m wide dynamically positioned heavy lift and pipelay vessel “Pioneering Spirit”, is designed for the single-lift installation and removal of large oil and gas platforms and the installation of record-weight pipelines. In August 2016 the vessel successfully removed the 13,500 t Yme platform in a single lift, setting a record with its first commercial contract. 

The emergence of “Pioneering Spirit” signifies a step-change in offshore installation and decommissioning. Designed to install and decommission platform topsides of up to 48,000 t and jackets of up to 25,000 t in a single lift, she will significantly reduce the amount of offshore work associated with installation and decommissioning by moving the work onshore where it is safer and more cost effective. Complementing the lifting systems is a 5000 t special purpose crane for additional lifts such as lighter topsides and jackets, modules and bridges. Moreover, with an S-lay tension capacity of 2000 t, she surpasses Allseas’ “Solitaire” as the world's largest pipelay vessel.  

The current trend of dismantling, lifting, removing and transporting heavy offshore structures, such as topsides and jackets, module by module is an expensive, high-risk activity for those involved. It also poses a serious threat to the environment. An entirely different concept, “Pioneering Spirit’s” unique single-lift capacity for platforms surpasses the capabilities of existing crane vessels, thereby extending the currently existing installation and decommissioning capabilities.  

For over 30 years, Allseas has developed cutting-edge technologies and has pushed boundaries in offshore technology. By continuously growing our know-how and expertise, we have developed into a world-leading offshore contractor. We continuously challenge ourselves to think outside the box to improve our business and the product of clients.

Allseas Group S A News

Decom North Sea logo
We're very sorry…

The browser you are using predates the modern web technology used to build it, making it impossible for you to use this site in the way it was intended to be used. Please update your browser to one of the following, and try visiting again: Mozilla Firefox, Google Chrome, Opera.