Engine condition monitoring provides a clear indication of performance, lubrication and wear conditions for slow-speed two-stroke marine diesel engines. This is achieved through detailed analysis of engine performance variables combined with advanced dilution analysis of used cylinder, fuel and system lubricating oils.
Through this holistic diagnostic approach, we can help identify any issues before they become problematic, provide practical guidance and pinpoint corrective actions.
How does engine condition monitoring work?
We analyse eight key condition indicators that significantly affect the efficient operation of your engine:
- Fuel oil quality.
- Air cooler and scavenge air.
- Combustion performance.
- Cylinder oil feed rate.
- Cylinder drain oil condition.
- Liner and ring wear.
- System oil condition.
- Engine performance indicators.
This is combined with advanced dilution theory (Flame ADT) from Flame Diagnostic, which normalises the effects of dilution within the system drain oil to allow meaningful analysis to be carried out. Without this vital process, changing conditions may not be revealed.
Through the combination of eight-point analysis and ADT, we provide greater insight into the performance of marine engines. This can result in benefits such as:
- reduced cylinder lubricating oil consumption
- less unplanned downtime due to repairs
- more fuel efficient operation, leading to reduced emissions
- reduced maintenance costs.
The benefits of managed optimisation – cylinder lubricating oil feed rate
For most large two-stroke engines, which are likely to be operating with a cylinder lubricating oil (CLO) feed rate of around 1.0 – 1.6 g/kWh, greater control can normally be achieved by using mechanical feed rate systems.
However, there can still be a tendency to over-lubricate since there is no way to provide confidence to the ship’s engineers that rate reductions are appropriate to the operation of each specific engine. Fitting wear detection systems can only show that wear is occurring and will not reveal underlying conditions.
The extra savings which can result from using a targeted optimisation programme such as engine condition monitoring can be significant, especially when considered over the fleet. For a ship achieving a 1.0g/kWh feed rate, even a modest 0.1g/kWh reduction in feed rate will represent a significant cost saving.
For example, based on the standard calculation, a hard working engine rated at 50,000 kW, operating at 85% MCR for 7,000 hours annually with a nominal CLO consumption of 1.0g/kWh, will use 297.5 tonnes of cylinder oil per year. At US$ 1,700 per tonne, the annual cost will be US$505, 000. A feed rate reduction over the year of 0.1g/kWhr will net a reduction in CLO usage of almost 30 tonnes, yielding a return of US$ 50,000.
Savings such as this are only made possible by the combination of FOBAS Engine’s eight-point analysis and the application of Flame ADT.
Without any capital expenditure, engine condition monitoring offers a significant increase in day-to-day knowledge of operational engine performance. This can empower shipboard crews, allowing staff to make the necessary adjustments to achieve an optimum operational condition and can help ensure that unforeseen problems are identified much earlier.