A small-bore, two-stroke engine being built by Makita for a chemical tanker will be the first Japanese-built prime mover with has ABB’s latest low-speed turbochargers
Introduced in 2019 by ABB Turbocharging, the A255-L turbochargers will be applied on a 6S40ME-B9.5 engine being built by Makita, which manufactures small-bore, two-stroke MAN engines under the license. The A255-L is designed to provide high turbocharging efficiency from a small unit, reducing overall engine size, providing ship designers with greater flexibility in engine room design for small bore two-stroke marine engines.
The engine and A255-L turbochargers completed shop tests and delivered the units to the shipyard. Makita’s tests confirmed good turbocharger performance across the entire load range, with turbocharger efficiency exceeding 70%, reports ABB Turbocharging.
The A255-L is based on ABB’s long-established A200-L design and provides benefits both in capex and opex by reducing the turbocharger footprint. The turbochargers are designed to be compatible with NOx and SOx abatement technologies, helping shipowners comply with future regulation on air pollution and greenhouse gas (GHG) emissions.
Scaled down from ABB Turbocharging’s A100-L and A200-L designs, the A255-L and the A260-L – introduced at the same time – are designed to operate on all fuel types and on engines specified for both IMO Tier II or Tier III emissions levels. The turbochargers are designed mainly for smaller vessels of 10,000 to 40,000 dwt that use small bore two-stroke engines. Typical vessels include bulk carriers, tankers and car carriers, many of which are built in Asia.
Both A255-L and A260-L turbochargers can be used on low-pressure, Otto-cycle dual-fuel engines to optimise combustion, improving engine efficiency while lowering GHG emissions. The high turbocharging efficiency provided by the new compact turbochargers maintains high air-fuel ratio in high-load operation, reducing the tendency for fast combustion which can adversely affect operation and emissions. The A255-L and A260-L turbochargers also facilitate the utilisation of emission abatement technologies for NOx and SOx reduction.
A manufacturer of marine engines for over 100 years, Makita builds marine engines for vessels between 10,000 and 40,000 dwt, with a number of ‘firsts’ to its credit. In 1982, Makita completed the 4,080-hp Makita-Mitsui-B&W 6L35MC engine, the first of its type in the world. In 2013, when Makita began production of the MAN B&W’s ME Series using electronic control, it built two of Japan’s first engines of this new type, the S46ME-B and the S35ME-B, followed by manufacture of the first S30ME-B in 2014.
“As an engine manufacturer, downsizing, weight reduction and high turbocharger efficiency are very important,” said a Makita spokesperson. “A highly reliable turbocharger is particularly important for chemical tankers as service opportunities are limited.”
ABB head of global sales low-speed turbochargers Alexandros Karamitsos, added: “Coming at a time when cost pressures are increasing, the order from Makita demonstrates both the high performance and the competitiveness of A255-L.”