The trend for increasing power density in turbochargers is advancing with the release of two compact models for small and medium-bore two-stroke engines.
ABB Turbocharging’s A255-L and A260-L, unveiled at CIMAC World Congress, build on the turbocharger platform first developed in 2009 with the launch of its A100 model. High turbocharging efficiency has been retained while size, weight and service costs have been cut. While the A165-L cut service cost by 10% and weight by 28% compared to the previous TPL73-B model (launched in 1999), the A255 and A260 reduce service cost by 30% and weight by 50%.
ABB Turbocharging head of global sales low-speed turbochargers Alexandros Karamitsos said: “Further focus will be placed on turbocharger efficiency in the future, alongside higher compressor pressure ratio demands, to enable two-stroke engines to reach their full potential. Our new turbochargers will deliver the highest levels of turbocharger efficiency and power density while enabling small-bore two-stroke engines to achieve lower fuel consumption and comply with emissions regulations.”
The two new frame sizes are suitable for two-stroke engines typically used on vessels up to 40,000 dwt including bulk carriers, tankers, container feeders and car carriers. They can be used with either diesel or dual-fuel engines, and in conjunction with NOx or SOx after treatment.
A range of matching components will be available to fit specific engine builder requirements. ABB Turbocharging said the new units fit into its ‘dry dock-to-dry dock’ service approach, requiring no intermediate turbocharger inspection between overhauls.
The A200 series was introduced in 2013 as a response to slow-steaming, with a higher volume flow contributing to fuel efficiency as opposed to the higher pressure ratios and power outputs sought by the earlier A100 versions. While the design approach has been adapted to reflect ship operation trends, the focus on improving power density has remained a steady focus for all turbocharger companies. This contributes to the Energy Efficiency Design Index – allowing more power to be squeezed from smaller engines – and offers greater flexibility in engine room design.