TS-66
Relation between Recent Low Grade Fuel and Reliability of Marine Diesel Engines
Yuji WAKATSUKI*, Kei WATANABE*, Tetsuya YAMAMOTO*, Tatsuo TAKAISHI**
ABSTRACT
On the piston running behavior, low speed two-stroke diesel engine has been improved in many aspects, and further efforts are being made for higher reliability. On the other hand, as well known for the adverse factors outside of the engine, fuel originated ones are majors to the piston running behavior. In this paper, these factors are spot-lighted, which would be a useful information to the shipowners and operators for safe operation of the vessels, we Mitsubishi Heavy Industries, Ltd. (MHI) do believe.
Key words: Low speed diesel engine, FCC catalytic fines, combustibility, ULO, low sulfur content
1. Introduction
A special task force was organized in MHI with their specialists in R & D centers in order to thoroughly investigate the influence of the recent low grade fuel oil with the collaboration of shipowners and oil suppliers. And detailed investigations revealed that the recent low grade fuel oil has following four adverse factors to piston running behavior;
1) FCC catalytic fines
2) Improper combustibility
3) Used Lubricating Oil
4) Low sulfur content
2. History of cylinder liner excessive wear
In Fig. 1, one typical example is given on the damage caused by low grade fuel oil. Cylinder liner excessive wear occurred just after using fuel oil from a certain supplier. And after changing the supplier of fuel oil, these excessive wear completely ceased.
Furthermore, excessive wear happened after using fuel from the same supplier on other 4 sister vessels, which were in service for Far East to North Pacific Ocean route. (Fig. 2) On the other hand, another sister vessel (#6) in Far East to Europe route had never experienced excessive wear.
Fig. 1 History of cylinder liner wears
Fig. 2 Relation between the supplier of fuel oil and the cylinder liner excessive wear
* Mitsubishi Heavy Industries, Ltd.
Kobe Shipyard & Machinery Works
1 -1 -1 Wadasaki-cho, Hyogo-ku, Kobe 655-8585 Japan
FAX: +81 -78-672-5985
E-mail: yuji_wakatsuki@kind.kobe.mhi.co.jp
** Mitsubishi Heavy Industries, Ltd.
Nagasaki Research & Development Center
