DCV Balder is a Deepwater Construction Vessel (DCV) operated by Heerema Marine Contractors

Heerema Marine Contractors

Heerema Marine Contractors is a contractor most notable for operation of three of the largest crane vessels in the offshore industry.-History:...

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The Balder was constructed in 1978 as semi-submersible

Semi-submersible

A semi-submersible is a specialised marine vessel with good stability and seakeeping characteristics. The semi-submersible vessel design is commonly used in a number of specific offshore roles such as for offshore drilling rigs, safety vessels, oil production platforms and heavy lift cranes.The...

 crane vessel

Crane vessel

A crane vessel, crane ship or floating crane is a ship with a crane specialized in lifting heavy loads. The largest crane vessels are used for offshore construction. Conventional monohulls are used, but the largest crane vessels are often catamaran or semi-submersible types as they have increased...

 by Mitsui Engineering & Shipbuilding Co., Ltd.

Mitsui

is one of the largest corporate conglomerates in Japan and one of the largest publicly traded companies in the world.-History:Founded by Mitsui Takatoshi , who was the fourth son of a shopkeeper in Matsusaka, in what is now today's Mie prefecture...

. Balder and sister vessel, Hermod

Hermod (ship)

SSCV Hermod is a semi-submersible crane vessel operated by Heerema Marine Contractors.-History:Semi submersible crane vessel Hermod was constructed in 1979 by Mitsui Engineering & Shipbuilding Co., Ltd.. Hermod and sister vessel, Balder were the world's first semi-submersible crane vessels...

 were the world's first semi-submersible crane vessels. In the early 1980s these vessels set several lift records while operating in the North Sea. Conversion to a DCV was carried out in 2001 by Verolme Botlek BV in the Netherlands

Netherlands

The Netherlands is a constituent country of the Kingdom of the Netherlands, located mainly in North-West Europe and with several islands in the Caribbean. Mainland Netherlands borders the North Sea to the north and west, Belgium to the south, and Germany to the east, and shares maritime borders...

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The hull consists of two floaters with three columns each.