Piling on the pressure and staying flexible
Installation contractor Seajacks has used Damen’s Shipdock subsidiary to good effect to prepare some of fleet for tough offshore assignments. Seajacks was a major installation contractor on the Meerwind* wind farm offshore Germany where it deployed two of its vessels, Zaratan and Leviathan to install foundation piles, transition pieces and turbines.
“We were responsible for a series of sub-contractor services to complete the main installation and there was benefit for us mobilising in Holland.” explains Alex Low, contracts manager for Seajacks. Seajacks transported and installed 80 monopile foundations – each 675 tonnes and 68 m tall – plus 80 transition pieces and turbine generators. To do this, the Zaratan had to be equipped with a specialised pile guide tool which was installed by the Damen Shipdock shipyard in Amsterdam, the Netherlands. A competitive tender was prepared for the scope of work on Zaratan, which Shipdock won and executed. This involved installation of grillages, and the piling system which allowed monopiles to be upended and positioned in one exercise. Also there was electrical work, sea fastening and welding.
“This was the vessel’s first job,” Low recalls, as the newly built Zaratan was prepared for Meerwind immediately after delivery from Lamprell’s rig construction yard in Abu Dhabi. “We had a very good working relationship with Shipdock from day one,” says Low. “I was the overall project manager for Meerwind and Shipdock was very good and they worked with us and developed a good planning document and a good time schedule.
“One of the biggest challenges for us was that we had to go into a shipyard, and hand the shipyard a scope of work. But separate to that we had to plan and fit it around the shipyard’s own workscope.” Low says careful preparation was necessary: “We had to plan all these works and execute it and one of the benefits of Shipdock was supporting us with that planning and remaining flexible and accommodating us.”
The Zaratan schedule was always subject to change by the delivery of critical supplies and the time taken for specific work. “Shipdock really did strike up a partnership approach with us, where we had a very efficient relationship with a common goal of getting the vessel mobilised on time,” Low remembers. Zaratan arrived mid July 2012 and left at the end of August.
Because modifications were so well planned, Seajacks mobilised Zaratan for a turbine maintenance assignment at Dong Energy’s Gunfleet Sands wind farm in the midst of the modification programme, but still completed the vessel on time. Low says this could only have been achieved through a good working relationship with Shipdock.
Seajacks turned to Shipdock again to modify the Seajacks Leviathan, to replace a 300 tonne Huisman crane with a 400t Kenz crane, which involved significant reinforcement of the jackup’s hull – “…Really invasive work to the hull structure,” Low says, as well as further equipment modifications and associated electrical and testing work. “Shipdock did a very good job. We were there on site with our superintendents for the whole process and it went very well, on time, on budget and it was done to a very good quality.”
Leviathan arrived at Shipdock in July 2012 and left early September. It has returned since for a five-year re-certification survey, and another Seajacks vessel may also use Shipdock in future.
For Low what differentiates Shipdock is the attention to detail: “They submit the right level of detail and planning.” As a quantity surveyor by training, Low says Shipdock staff were clear during meetings and that was apparent in clarification sessions.
“The evidence came from their documents, and they were very open in clarification meetings, and we were able to strike up a very good working relationship. Delays are not desired and they have a big [financial] consequence …which is a key service they provide.”
* WindMW is the German owned company responsible for development of the Meerwind project, backed by Blackstone the New York, US headquartered private equity group.