Focus on sustainability
As emissions are caused by burning fuel, it is only natural that an engine that consumes considerably less fuel also produces significantly fewer emissions. The brand-new Wärtsilä 31 not only complies with the existing IMO Tier II emission standard, it also meets the IMO Tier III legislation that came into force in the beginning of 2016. Moreover, the dual-fuel concept allows vessels easily to switch between diesel and gas, depending on where they are operating.
“As the market leader in fuel efficiency, the vessel will produce a significantly lower amount of CO2, CO, THC and SOX. With the dual-fuel version, it can operate on diesel in a Tier II area and then switch to gas when it enters a Tier III area (such as an Emission Control Area, or ECA). The switch is instantaneous – there’s no need to wait for the change-over – the vessel can just carry on sailing at the same speed.”
Less maintenance, more uptime
As regards maintenance, the costs associated with the new Wärtsilä 31 have been reduced by approximately 20%. Whereas standard engines of similar output require a first maintenance stop after about 1,000 operating hours, the first stop on the new engine takes place after 8,000 hours.
“Because we know how crucial uptime is to our customers’ profitability, reducing the need for maintenance was one of our top priorities for this new engine,” explains Åstrand. “Not only do its components have a longer lifetime, we’ve also invested a great deal of energy in reducing the amount of time needed to maintain it.”
Remote access to operational data enables advanced support and immediate response from Wärtsilä to ensure the vessel´s or power plant’s safe operation regardless of its location. A dedicated expert with senior level technical experience gives advice to the crew via phone and e-mail. This reduces unscheduled maintenance visits on board.
The modular design of the new Wärtsilä 31 allows for entire engine modules easily to be taken out and replaced. This reduces maintenance time as a module can simply be exchanged, instead of dismounting each individual part.
“This shift from single spare parts to ‘exchange units’ – meaning the replacement of complete units or modules, such as power units, injectors and high pressure fuel pumps – contributes to more efficient servicing and maximises uptime,” says Åstrand.
When an engine requires maintenance, downtime will be drastically reduced as an entire module can simply be taken out and replaced by an exchange unit. The exchange modules are listed in the spare part manual and available from stock.
Operational flexibility is a major concern for offshore applications as many vessels operate at low load but also require fast power-taking capability. Operators need to ensure that they can operate at low loads while maximising fuel efficiency and profitability. The Wärtsilä 31 can easily be adapted for different operating profiles, with a variety of tunings, thanks to the advanced engine automation system combined with the flexibility of the fuel injection and air admission systems. Further improvements for low load operations can also be achieved by installing the low load efficiency package, which includes some mechanical changes.
“Thanks to an extremely high level of automation, we’ve been able to optimise several points that we wouldn’t have been able to adapt in the past,” explains Tirelli.
“Many mechanical systems couldn’t be tuned for different operating profiles, but modern electronic and hydraulic systems are easy to adapt to match the operating needs of the customer,” agrees Åstrand, adding that if an owner wants to change the way an existing vessel operates, it can always be re-tuned to match the new requirements.