The Mobilgard 570 is a special anti-wear cylinder oil designed to extend piston ring and liner life.
Costamare Shipping, Athens, Greece, the owner of Cosco Yantian has, in consultation with Field engineers from ExxonMobil, introduced Mobilgard 570 anti-wear cylinder oil and the MobilGard CCM programme. As a result, they have been able to triple the piston ring replacement period. What had a life of 16,000 hours was extended by more than 55,000 hours of continuous use. The wear-and –tear of liner wear was noted to have improved greatly resulting in the reduction in cost and optimal vessel performance.
Container ship Cosco Yantian of Dwt 107,498 tons is fitted with MAN Diesel & Turbo 12K98MC MK7 engine and the regular piston overhaul interval for it was 16,000 hours of unmonitored operation. The vessel in her worldwide operations has noted an overall slow steaming in the 10 to 40 % load range; this has proved to be non-viable in the long run.
Extending overhaul periods
Engineers gradually extended the overhaul period on successive pistons in the vessel’s 12-cylinder engine. Overhauls started at 16,000 hours (the MAN recommended interval) and continued systematically at extended intervals, based on the good condition of the engine’s pistons, rings and liners. In cylinder number 11, the overhaul was done at 42,575 hours, with scavenge air port inspections showing that all monitoring parameters were still within the normal range.
Cylinder Condition Monitoring (CCM)
MobilGard Cylinder Condition Monitoring (CCM) can help operators to identify the most appropriate Base Number (BN) cylinder oil, in order to optimise engine feed rates and extend piston overhauls. It can help Control cold corrosion, Extend engine life and Decrease maintenance costs through a series of on-board tests and lab analysis which helps produce real time data on cylinder operating conditions.
Field marketing manager for ExxonMobil Marine Fuels & Lubricants, Iain White is quoted to have said “Cosco Yantian’s piston overhaul intervals were extended by 250 per cent, with wear measurements sitting well within acceptable parameters after more than 55,000 hours of operation. By combining Mobilgard 570 with MobilGard CCM, Costamare Shipping was able to realise considerable financial benefits.”