MV Lone successfully converts into pipelaying vessel for First E&P’s Madu/Anyala Surf 1 offshore campaign in Nigeria

Oil was discovered in Nigeria in 1956, with production starting just a few years later. Since then, with some exceptions due to economic circumstances, the Nigerian oil industry has grown constantly to become a – global giant. Nowadays, Nigeria is Africa’s main oil producer: With 18 operating pipelines and an average daily production of over two million barrels in 2019, Nigeria ranks eleventh among the largest oil producers world-wide.

With its latest job in Nigeria, MV Lone not only took a huge step in supporting the Nigerian oil industry, but most notably got to demonstrate the diverse opportunities that SAL can facilitate within the offshore market. The innovative thinking of SAL’s engineering experts made it possible to use every centimetre on deck of MV Lone in order to transform the heavy lift vessel into a well-equipped pipelaying vessel for an important Nigerian offshore campaign.

Although the Madu / Anyala Surf 1 campaign was not SAL’s first offshore job in the waters of Nigeria, it certainly was a oneof-a-kind project: “It leaves us with great pride that we succeeded in transforming our heavy lift vessel MV Lone into a pipelaying vessel. This gave us the opportunity to get involved in our first lay project of flexible flowlines and umbilicals,” said SAL’s Director Business Development (Africa) Paul Okpurughre.

For SAL, the project scope included special purpose vessel (SPS) mobilization, the loading of a carousel and two reels, the spooling of flexible flowlines and umbilicals, the loading of a midwater arch, as well as the mobilization of a lay system for the J-lay installation. It also included the installation of the midwater arch on the seabed as well as the placement of the above-mentioned flexible flowlines and umbilicals in J-lay method.

The mobilization of MV Lone took place in Rotterdam (NL), Hartlepool (UK), Rosyth (UK) and Lagos (NGA) over a total of 57 days. In Rotterdam, the weather deck was reinforced with underdeck stanchions to accommodate the carousel, which weighed 1450 tonnes, as well as the pipelay tower and temporary living quarters with space for an additional 78 people. Two spooled reels were also added.

In Rosyth, umbilicals from three reels were directly spooled to the carousel. After sailing to Hartlepool for another transpooling of umbilicals to the carousel, the midwater arch, two rigid risers and four pieces of 25 m pin piles were loaded in Rosyth. The last stop for the mobilization of MV Lone was in Lagos, where two ROVs and other equipment were added to the vessel.

“It took thorough planning to mobilize MV Lone according to the project requirements and to make sure we were able to fulfil the project scope without having to return to port to pick up further equipment,” explained Paul Okpurughre. “It was quite an engineering challenge,” he continued, “but in the end, we succeeded in transforming our vessel MV Lone into a proper pipelaying vessel. All despite the fact that the beginning of the corona crisis made it quite difficult for all involved parties to get their staff where needed.”

The deployment of a 21 metre-tall subsea structure, the so-called midwater arch (21.4 × 19.7 × 14.4 metres, 130 tonnes), was carried out using MV Lone’s Fly-Jib. “To fulfil all project requirements, it was crucial to enlarge MV Lone’s lifting height and outreach. Luckily, we were able to meet the clients’ demands with our Fly-Jib and safely installed the midwater arch on the seabed,” said Paul Okpurughre.

Following the installation of the midwater arch, four risers (51 × 3 metres, up to 30.5 tonnes each) were lifted, stored underwater and later installed by another vessel. “In my opinion, the most exciting part of this project was the lay operation of about 26 kilometres of flexible flowlines and umbilicals. We not only did this in DP mode, using the J-lay method, and near a drilling rig, but also at a tremendous speed of up to 760 metres per hour – almost as fast as a proper pipelaying vessel,” explained Paul Okpurughre with pure excitement. “With a total of 100 people on board, and despite the challenges the COVID-19 pandemic confronted us with, I am thankful for the amazing opportunity this project presented us at SAL,” he continued. “Without the great teamwork of all parties involved and the collaborative efforts of everyone, it would not have been such a successful story to tell.”

The offshore work for the Surf 1 campaign took 30 days and marked a significant step in the development of the Anyala and Madu fields.