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Yunlin Project Blog

Yunlin Blog – Steel fabrication with Sledge Hammer

18 Feb 2021 – Operating as a partner instead of just a supplier

Jumbo contracted Sledge Hammer to fabricate almost 3,000 tonnes of seafastening components for its Yunlin transport scope. Here, Sledge Hammer Managing Director John Dorreman highlights the importance of early involvement in engineering to create a win-win situation for all parties.

Yunlin is a 640MW offshore wind farm under construction off the coast of Taiwan. It is being developed by German onshore and offshore wind farm operator wpd, the Starwind Offshore consortium and Greenwing Energy. Jumbo was contracted to execute the transportation and (part of) the installation of Yunlin’s wind turbine substructures. This series of Blogs takes a closer look the work involved.

Can you tell us about Sledge Hammer. What do you do? Who are your clients?
Sledge Hammer is an offshore contractor for the fabrication of grillages and other seafastening structures. We also support clients with the mobilization – outfitting of seagoing barges and heavy lift vessels – and demobilization – clean offs – of their projects. Among others, our main clients include Jumbo, Saipem, Heerema, Seaway Heavy Lifting, Allseas, Cosco, and Scaldis.

How did Sledge Hammer get involved in the Yunlin offshore wind farm project?
What happened in this project was very rare for us. It started with Jumbo inviting us to make a presentation to their client wpd. We used that opportunity to introduce our company to wpd; to show that Jumbo had made the right choice in choosing Sledge Hammer. wpd was happy, and the ball started rolling from there.

What was the first step?
In the engineering phase, we had several meetings with Jumbo to improve the engineering and translate this to common practice. This procedure went very well and Jumbo was open for discussion; they create the right atmosphere for this collaboration. When we approach a big project like this, we like to sit around the table with our client and see what challenges need to be sorted out. If you do this in the early stages, then it is a win-win for everybody. If you wait until the engineering is finished, then you are too late. The engineering package has already gone to all the stakeholders – the client, the classification societies, and the surveyors.

What was Sledge Hammer’s scope of work?
We split the fabrication into two batches. The first batch was for 48 saddles and 96 load spread beams with a total weight of 1,722 tonnes. We finished this batch in 15 weeks, averaging 115 tonnes of production per week. The second batch was for 32 saddles, 64 spreader beams and 64 interfaces, again with a total weight of more than 1,000 tonnes and averaging more than 100 tonnes of production per week. We also worked with Jumbo on six vessel mobilisations, installing grillages with the assistance of their crews

Did the Yunlin project give you any challenges?
In terms of welding procedures and general quality demands, this was standard for Sledge Hammer. The biggest challenge was due to the volume; at 2,800 tonnes, it was a big job. We have quite a big workshop, but it was a continuous process to create space. However, we are used to working under time pressure – for example; I have 30 years of experience in this line of work. We completed both batches a couple of weeks ahead of schedule and within the agreed budget – that was good stress relief for all.

Can you describe the process of working with Jumbo?
We at Sledge Hammer are lucky with Jumbo because we have matching mentalities; this is very positive. We have to earn money, but always in a safe way, with decent social behaviour to all parties involved. We try to deduct costs for our customers, but we understand that achieving the agreed delivery time is more important than the price alone. In the offshore industry, having the best price but not being reliable will kill your company.

It is clear that you understand the dynamics of the supply chain.
Indeed. We are not a VOR-minded [Variation Order Request] company. We try to offer a lump sum price that can be expected from our experience and common sense. What’s more, we like to operate as a partner and not just as a supplier. This is actually one of the lessons learned from Yunlin. We work with Jumbo’s sales department during their tendering phases, aiming to achieve efficiency in the required structures and lower prices; resulting in higher scoring rates for Jumbo.

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