30 Nov 2021

An update on the construction of the Combat Support Ship

The selection of Wärtsilä 31 diesel generators was based on the ambition to ensure that the CSS is as efficient as possible in terms of fuel consumption and exhaust emissions

Rick van de Weg

Installing four of the world’s most efficient four-stroke gen sets and 8,000 pieces of piping

Just over six months since the keel-laying of the Royal Netherlands Navy’s Combat Support Ship (CSS) at its yard in Galati, Romania, and Damen Naval is pleased to report that construction of the 179-metre long vessel is on track.

Damen’s design for the CSS consists of a total of 178 different sections. The construction drawings of 116 sections have been finalized, 80 sections have already been fabricated at the yard, and 22 are currently under construction, together representing a total amount of cut steel of 6,600 tonnes. Damen Naval project director Arjan Risseeuw describes the scene at the yard: “It’s starting to take shape – the whole yard is full of pieces of ship and we are slowly starting to put them together.”

Diesel Generators milestone

The construction of the sections is taking place at the same time as the installation of some equipment. This equipment includes small items – for example, more than 8,400 pieces of pipework have been fitted into the finished sections – as well as larger items. In fact, last month saw the placing of the heaviest items of equipment: four Wärtsilä 31 diesel generators. The selection of this generator by Damen Naval and the Defence Materiel Organisation (DMO) was based on the ambition to ensure that the CSS is as efficient as possible in terms of fuel consumption and exhaust emissions.

With that in mind, the Wärtsilä 31 will go a long way in achieving that goal. It is equipped with a selective catalytic reduction unit that will ensure that the CSS is compliant with IMO Tier III regulations concerning NOx emissions. It displays optimum fuel efficiency across its entire operating range and has even been recognised by Guinness World Records as ‘the world's most efficient four-stroke diesel’. Combined with the hull shape and propeller design, the Wärtsilä 31 will reduce the CSS's fuel consumption by about 6 per cent.

Furthermore, Damen has worked closely with Wärtsilä and DMO on reducing the levels of noise and vibrations of the four generator sets. To this end, the engine and generator have been built on a base frame structure. “Placing the generator sets in the sections was a real feat. Now that they are in place, the sections can be built over them,” Risseeuw adds.

Looking on to 2022

The construction of the CSS continues alongside the passing of the project’s key milestones. “If we look ahead, there are a number of highlights coming up,” says Risseeuw. “At the beginning of February, we will be pulling the first cables. And another big event is the lateral launch of modules 2 and 3 in April. In addition, we are busy with the engineering and construction of a float so that we can move the hull from dry to wet dock.”

Throughout the CSS project, Damen Naval has been keen to note that the construction of this naval vessel is a collaborative effort between DMO, Damen Naval and a large number of Dutch subcontractor companies. To date, 133 such supplier contracts have been awarded. 98 of these contracts, with a total value exceeding EUR 110 million, bring in the involvement of Dutch maritime companies. “Every project is special, and it is nice to be able to build a ship for our own Royal Navy again after ten years. And having so many Dutch suppliers involved is the icing on the cake!” Risseeuw concludes.