Wärtsilä Dual-fuel Engines for LNG Carrier Newbuilds
Each of the four 174,000 m3 capacity vessels will be fitted with four Wärtsilä 34DF dual-fuel generating sets running primarily on LNG fuel to provide the ships with auxiliary power. Their total power output will be 56 MW. Among the reasons given for the Wärtsilä 34DF engine being chosen for these ships were its proven reliability, efficiency, and economic fuel consumption. Delivery of the engines to the yard will commence in the second half of 2018. The vessels are scheduled to be delivered commencing in 2019.
Wärtsilä is reporting that its continuing positive order trend from reputable international LNG carrier owners is the result of the company's advanced technologies, especially in gas and dual-fuel engine applications. Furthermore, the company's extensive global service network, which is unmatched in the marine sector, is often cited as a major factor in the decision to purchase from Wärtsilä.
The Wärtsilä 34DF engine features advanced dual-fuel technology, and is known for its efficiency. It is used for both main engine and generating set applications. The Wärtsilä 34DF is manufactured in configurations from 6L to 16V, giving 500 kW per cylinder and a total maximum mechanical output of 8000 kW. The engine speed is 720 / 750 rpm.
Based on the Wärtsilä 32 diesel engine introduced in the mid-1990s, the engine's fuel flexibility means that it can be optimised for constant speed generating sets, as well as for variable speed mechanical drives in main engine applications. The Wärtsilä 34DF dual-fuel engine was upgraded in 2013 with a higher MCR (maximum continuous rating) and better efficiency than its earlier version, the first of which was delivered in 2010. Furthermore, the special efforts made to upgrade the propulsion performance with controlled pitch propellers (CPP) are now being applied also to fixed pitch propellers (FPP). The mid-range capabilities of the Wärtsilä 34DF are considered as being the benchmark for gas fuelled engines.
The 100th Wärtsilä 34DF dual-fuel marine engine was delivered from the factory in 2016.