Dutch heavy lift firm Hereema Marine Contractors has tested what it says is a revolutionary new way of heavy lifting offshore utilizing two dynamically-positioned vessels, four massive cranes, and a combined lift capacity of more than 20,000 metric tons.
The so-called “QUAD” lifting technique was developed in-house by Hereema as an easier, less-costly way for installing and removing oversized topsides or jackets offshore.
The first test of the technique was successfully carried out on Oct. 22 in the Gulf of Mexico using Hereema’s Thialf and Balder, which are two of the largest semi-submersible crane vessels in the world.
For the test, Thialf and Balder worked in parallel to lift a single load using their four cranes and combined lifting capacity of more than 20,000 tonnes – comprising Thialf’s 14,000 t lift capacity and Balder’s 6,400 t capacity.
In the future, the total capacity using the QUAD technique will made even greater with the arrival of the 20,000 t capacity Sleipnir currently under construction at Sembcorp Marine in Singapore.
“We are proud of the excellent test results with two dynamically-positioned vessels with four cranes working in parallel: Thialf and Balder, two of the world largest semi-submersible crane vessels, both owned and operated by Heerema. As soon as Sleipnir, the largest semi-submersible crane vessel ever built, is in full operation, we are ready to perform the ultimate QUAD lift using our two giants with a combined lifting capacity of Thialf’s 14,000 t and Sleipnir’s 20,000 t”, said CEO Koos-Jan van Brouwershaven of HMC.
The new QUAD lifting method and technology was certified international classification society DNV-GL. Hereema called the technology an an important expansion of HMC’s services as way to lower overall project costs.
“We are looking forward to this with great confidence,” added van Brouwershaven. “With our QUAD lifting method, we definitely enter a new era with more flexibility and efficiency throughout the entire process – from engineering, procurement and construction up to and including the commissioning and installation of the jacket and/or the topside – with lower project costs as a result.”