Arctic aspirations

With a major Russian Arctic contract already in the bag for next year, the Tideway Group is looking at early payback on its €115 million investment in the industry's first ice-class fallpipe rockdump vessel.

Dubbed Flintstone, the DP2 vessel was launched at Singapore's Sembawang shipyard in April and is expected to be operational in northwest Europe from 1 April next year, quite possibly making its rock placement debut in company with its two sister vessels Rollingstone and Seahorse during the latter stages of Tideway's huge contract with Saipem for Nord Stream gas pipeline post-lay protection works.

Pioneering and challenging Barents Sea work also beckons for Flintstone following the recent contract award by Russia's Sevmash for scour protection around the Prirazlomnaya concrete gravity based oil platform to be installed by Global Maritime near Murmansk. It was this job, the precursor to other upcoming projects in the region such as Shtokman, that persuaded Tideway to secure ice class notation for Flintstone through Lloyd's Register. ‘No other fallpipe vessel can do a project like that; it's the only vessel with an ice class,' enthuses Tideway director Hugo Bouvy.

The company's first fallpipe vessel newbuild has other impressive attributes too, adds Bouvy, with a lot of advantages expected to stem from the purpose-built dimension.

Sizewise, with a load carrying capacity of 19-20,000t, Flintstone represents a substantial scaling up on the company's earlier fallpipe vessel conversions – Rollingstone (11,500t) and Seahorse (17,500t) – yet although roughly double the size of Rollingstone the newcomer will be just 15m longer. It's much wider though – 32m in all – making Flintstone's design transit speed of around 15 knots all the more impressive. Bouvy expects this feature, along with the vessel's draft of only 7.85m when fully loaded, to be a decisive factor on the bigger and more geographically diverse oil & gas projects his company is encountering today in places like Mexico, Canada, Russia, Australia, Brazil, India, Vietnam, Angola and northern Norway.

‘This is very much our next-generation vessel,' says Bouvy. ‘People tend to think of rock placement as a very archaic and simple industry, but it's quite a sophisticated business now.'

As an example of the progress made, he points to Flintstone's advanced fallpipe design. Having established a world record water depth for fallpipes – 980m – with Rollingstone on the Balearic pipeline project offshore Spain last year, the company opted to put a system on Flintstone that could work in 2000m of water. But Tideway knew it would have to move away from conventional fallpipe designs with a combination of steel and GRP hanging from wires since at such depths the wires' elasticity would cause the fallpipe to ‘dance' as the vessel moved.

Tideway looked for a different solution, one in which the pipe would carry itself, and Flintstone will boast serial number 1. Borrowing from tubular handling and connection technologies more familiar to drillers, the company believes it has devised a system that not only deals with the weight problem but also remains very strong and facilitates quick assembly. The patented system, consisting of high tensile aluminium pipe sections joined by a double-bayonet type connector, involves quite a complex logistical chain that begins with the aluminium extrusion process at Alcoa's specialist Russian plant, then moves to an Alcoa facility in the US for connector and pipe welding and finally arrives in the Netherlands around the end of this year for coating and installation on the vessel. The pipes will lay horizontally on the deck and then be upended, drill pipe fashion, using a pipe handling system developed by Tideway in conjunction with Huisman in Schiedam (see page 77).

Broad way

Hugo Bouvy envisages Flintstone ushering in a new and more versatile era for the company as it seeks to broaden its market offering not just in the oil and gas sector, where rock placement and landfall work today generates 80% of revenues, but also in the wider energy and renewables arena which he expects will continue to provide the other 20%.

Flintstone's arrival, he believes, will free up fallpipe fleet capacity currently constrained by the demands of the new breed of international mega-projects such as the Nord Stream twin gas lines running from Russia to Germany via the Baltic. ‘That's an enormous project for us and by the time we have finished, around the end of 2012, we will have installed 2.5 million tonnes of rock, sourced from Finland, Sweden and Norway,' explains Bouvy. Seahorse started preparing the seabed for it on 1 March this year, with Rollingstone joining in mid-April, and the vessels have since gone back and forth between Finland and Russia. In September, Allseas' Solitaire is due to start laying pipe over the rock berms these vessels have created, following which Tideway will begin backfill operations.

‘We believe we are very well equipped for such projects, but we really need the new vessel otherwise we would have found our hands a bit tied by Nord Stream. And we would never want to be in a situation where we have to disappoint key customers. Flintstone will help relieve some of that pressure, while also allowing us to continue exploring other business opportunities presenting themselves today for DP2 vessels with a lot of deck space,' says Bouvy.

‘We can readily put a turntable on one of our vessels and start laying cables,' he adds, harking back to Tideway's involvement in the installation and protection of the first NorNed submarine power cable between Norway and the Netherlands (OE September 2007) and the installation through parent company DEME of all power cables for the Thornton Bank windfarm project. With Tideway now also pre-sweeping for the UK-Netherlands cable (BritNed), a second NorNed line under discussion and more interconnectors planned between Norway and Germany, Denmark and Norway, France and England, and Finland and Iceland, Bouvy rates this market as an ‘extremely interesting' one.

Interconnectors and the renewables sector also bring with them more conventional rock placement opportunities. Tideway, which has its head office in Breda, is contracted to provide the rock protection for the BritNed cable crossings and other sections along the route where trenching is not an option. The company also handled Thornton Bank's infield and export cables offshore Belgium and, having prepared the foundations for Dong Energy's Walney wind farm off the UK, Tideway's sidestone dumping vessel Pompei will return in October to provide scour protection around Walney's 52 monopiles. Next year another 52 monopiles will have to be installed for this project again requiring installation of foundations and rock dumping for scour protection reasons.

Tideway also recently picked up work on the UK South West Regional Development Agency's pioneering ‘Wave Hub' project, which requires the placement of rock to protect JDR Cable Systems' 16km power cable – in up to 50m of water off the coast of Cornwall – from fishing gear (see page 109).

‘We will also be able to do interventions with our new vessel,' concludes Bouvy, pointing out that Flintstone will come equipped with a mass flow excavation system which can be guided and monitored by the fallpipe's ROV system. ‘So potentially the one vessel can be deployed for soil and rock removal, pipe repair and reinstating the rock protection afterwards.' OE

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