First introduced at the turn of the millennium, MAN PrimeServ – MAN Diesel & Turbo’s service division – recently retrofitted its 20,000th slide fuel-valve.
Christian Ludwig, Head of Retrofit and Upgrade, MAN Diesel & Turbo, said, “Slide fuel-valves have proved to be very popular within the marine and two-stroke market. The slide fuel-valve’s strong market performance is testimony to the fuel savings and increased environmental profile it brings to working vessels. It is important to note that slide fuel-valves improve the low-load operating capability of engines.”
Slide fuel-valves come as standard on all new MAN B&W engines but can also be retrofitted on MC engines. The slide fuel-valve eliminates the so-called ‘sac volume’, which reduces fuel-oil consumption and, furthermore, eliminates dripping from the fuel-valve nozzle.
Compared to conventional valves, the slide fuel-valve has NOx-reduction potential. The reduced sac volume leads to an improved combustion process, resulting in fewer deposits throughout the gas ways and a reduction in overall emissions, such as HC, NOx and particulate matter. Furthermore, visible smoke conditions are also greatly reduced because of the improved combustion.
Engines fitted with slide fuel-valves have a significant advantage in an era where ‘slow steaming’ (sailing at part load) has become the industry norm. The improved low-load performance with regard to soot formation reduces the need to run at high revolutions in order to clean exhaust channels.
The procedure for replacing standard valves with slide fuel-valves is straightforward and can be carried out by ship personnel after instruction or MAN PrimeServ as required.