Compact Contender In High-Speed Stakes

Due to be introduced at the Euromaritime Exhibition in Marseilles next week, the 6F21 diesel covers a power band up to 735kW at 2,300rpm crankshaft speed and is characterised by a claimed ‘best in class’ power density.

As the latest outcome of the steady investment in Baudouin since its acquisition by the Weichai Group of China 13 years ago, the 127mm-bore addition to the portfolio incorporates a two-stage turbocharger system, two intercoolers and high-pressure common-rail fuel injection, operating at 2,200bar.

The engine structure is strengthened to withstand high torque and a cylinder pressure in excess of 200bar, although this has been achieved through the use of light materials, so as to keep overall weight down. Cast iron and steel have been employed only where stress and temperature criteria so demand. The flywheel housing, oil sump, covers, brackets, supports, and heat exchanger bodies have all been constructed from light alloys.

Conceived for the broad market spread encompassed by high-speed diesel power, the 6F21 is offered at three duty ratings, common to which is the 2,300rpm maximum rotational speed. Thus, the P3 intermittent duty model for pilot boats, small passenger vessels and workcraft, delivers 599kW, and the P4 light duty engine for military and fast rescue vessels, survey ships and other vessels turns out 662kW, while the P5 high-performance version, for the leisure market, yields 735kW.

With main dimensions of 1,470 x 1,100 x 1,075mm main dimensions, making for what Baudouin describes as “the most compact marine engine in our history”, the six-cylinder in-line 6F21 is suited to the smallest of machinery rooms.

Ease of maintenance has been an important tenet of the design project, as expressed in the adoption of individual cylinder heads, ease of access to key components without necessitating engine dismantling, and front mounting of fuel filters.

Weichai has ploughed more than EUR100m (US$105m) into Baudouin since taking over the 1918-founded company in 2009. In the first year of Chinese ownership, an R&D centre was opened at the Cassis headquarters, near Marseilles in southern France, giving rise to a new generation of engines. Recent years have seen the third iteration of the M26 high-speed type, wherein the common-rail structure has enabled compliance with the latest emission regulations, and the release of the M33 engine, which has helped increase penetration in the tug, workboat and fishing vessel sectors.

Subsequent work has included research into a dual-fuel engine for the marine market.

MAIN PARTICULARS – Baudouin 6F21 engine