Subsea 7 DSV undergoes engine overhaul
Royston has completed an overhaul of diesel engines on the 140-m (459-ft) long Subsea 7 diving support vessel Seven Atlantic.
Engineers undertook the 30,000 running hour service on the generator engines onboard the vessel as part of a general refurbishment and maintenance of critical power plant.
TheSeven Atlantic, built in 2009, is said to be one of the largest vessels of its type in the world, operating a 24-person saturation diving system.
Royston disassembled the Wärtsilä W7L32 diesel generator No.5 to install new cylinder heads, air start valves, indicator cocks, injectors, and cylinder seals.
Relief valves, pistons and conrods, cylinder liners, bearing blocks, crankshaft and turbocharger were sent to the company’s Newcastle workshop for checking and repairs before being returned ahead of the final reassembly and inspection of the engine.
In addition, the company overhauled the turbocharger on the Wärtsilä W7L32 diesel generator No.3.
Due to the need for a 12,000 running hour overhaul, the NA297 Napier turbochargers from both engines were removed, stripped, cleaned, inspected, and balanced at the company’s test and repair facility.
Royston engineers also undertook load testing in line with the engine manufacturer’s specification.
Shawn Doering, Royston’s service manager on the contract, said: “Our experience with the engine and vessel type ensured the work was carried out efficiently and effectively, enabling the vessel to return to sea-going operations as quickly as possible.”
TheSeven Atlantic’s power plant comprises six Wartsila 7L engines, each driving a 3360kVA Van Kaick generator, generating 6.6 kV (mains voltage). The propulsion installation runs on marine gasoil and provides power for propulsion, dive systems, crane activities and others.