Twelve mobile cranes in operation during the construction of a pipeline in Delft

Richard Rijbroek is an environmental manager at Denys and supervised the construction of the pipeline in Delft. The client is Nederlandse Gasunie NV. Rijbroek explains: "Preparations for the "WarmtelinQ" project have been underway for three years. We will use the residual heat from industry in the port of Rotterdam and from waste incineration plants to heat homes and businesses in South Holland." The pipeline runs from the port of Rotterdam to The Hague via Vlaardingen.

Cranes bend the pipeline into a predefined curve

A drill head was installed on one side of the 1,000 metre long district heating pipeline, as Harm van Dijk, project manager of the Dutch crane operator Boer B.V., explains: "We are drilling a bore here for the heating network. The pipeline is drilled into the ground." To do this, the pipeline has to be lifted up and placed in a certain curve so that it is drilled into the ground at a defined angle.

According to van Dijk, the length of the retractable arch is 275 metres: "To get the exact curvature, we form the arch with ten cranes. Each of these cranes lifts 18 tonnes. For this reason we need machines with a capacity of 90 - 140 tonnes here. On the other side of the motorway, we used a 300-tonne and a 400-tonne crane because of the large overhang." The kilometre-long pipeline cannot be completely pre-assembled on the ground, as a motorway and a bridge cross the route. It was therefore stored on containers at a sufficient height as required.