The excellent service experience with PLS can be indicated from this view of a piston ring pack in an RT-flex96C engine. |
Costs for cylinder lubricating oil are more and more becoming a critical issue for vessel operators with market prices for lubricating oil constantly rising while availability can be limited.
Wärtsilä has thus developed an electronically-controlled retrofit lubricating system to serve this demand for lower cylinder oil feed rates: the Retrofit Pulse Lubricating System (PLS). It delivers reduced cylinder oil consumption without compromising piston running reliability.
The guide feed rate for Wärtsilä RTA and RT-flex engines retrofitted with the Pulse Lubrication System is 0.8 g/kWh of cylinder lubricating oil.
Typical annual savings of well above US$ 200,000 can be achieved with the pulse lubricating system compared with the Wärtsilä Accumulator System for a Wärtsilä 12RTA96C engine operating for 7000 hours a year at an an engine load of 85% CMCR with cylinder oil costing US$ 1700/tonne. |
The reduction in cylinder oil feed rate allowed by the Pulse Lubricating System, compared with the existing accumulator system, is made possible through the improved distribution of cylinder lubricating oil to the piston rings and the fully flexible, precise timing of oil delivery.
The benefits of the Pulse Lubricating System are thus:
- Reduced cylinder oil feed rates and thus reduced engine operating costs
- Precisely timed delivery of lubricating oil to the piston rings package
- Accurately metered quantities of lubricating oil delivered to the piston rings package
- Improved distribution of cylinder oil on the liner.
The main components of the Pulse Lubricating System are:
- Pulse lubricating module, consisting of a dosage pump with electronically-controlled timing
- Lubricators, up to eight in a single row around the cylinder liner
- Filter and measuring system
- Servo oil supply unit (on RTA engines) or pressure reducing unit (on RT-flex engines)
- Control system
- Crank angle sensors, two of which one is redundant.
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Availability
The Pulse Lubricating System is available now for retrofitting to RT-flex96C and RTA96C engines, and will be available from January 2007 for RT-flex84T-D and RTA84T-D engines. Additional engine types will be added to these in 2007.
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Service experience
Service experience has been gained with the Retrofit Pulse Lubricating System both on the Wärtsilä RTX-3 research engine and on shipboard test engines. The first production engine fully fitted with Retrofit PLS successfully passed its shop test in May 2006, with other engines following.
The first Retrofit PLS test started on the RTX-3 research engine in June 2003. Shipboard testing began with a Wärtsilä RTA58T in September 2004 and later on an RT-flex96C engine. Shipboard testing has accumulated more than 14,000 running hours. Throughout the outstanding performance of the Retrofit Pulse Lubricating System was confi rmed, with all testing being at or below the guide feed rate of 0.8 g/kWh.
