TS-147
Development of Spray-Coated Cylinder Liner for Diesel Engine
Takao TANAKA*, Shinichi MIYAKE*, Shoichi TAGUCHI*, Takayuki GOTO*, and Thomas S. KNUDSEN**
ABSTRACT
As a material of the cylinder liner, a lamella graphite cast iron is applied for all Mitsui-MAN-B&W 2 stroke crosshead type diesel engines because of soundness of material strength and sliding performance against wear.
Recently, however, the required capability on the cylinder liner, especially for the sliding performance is being raised in accordance with the phased rating up of the engines.
For developing the cylinder liner to meet the severer load condition in the future, the improvement of sliding performance is considered as most necessary. As one of the influential measures, Spray-Coated cylinder liner is being developed.
This paper describes the development process, the production of a full-scale model and the service test experience of Spray-Coated cylinder liner.
Key Words: Cylinder liner, 2 stroke crosshead diesel engine, Sliding performance, Plasma coating, Wear rate
1. INRODUCTION
In these years, Mitsui Engineering & Shipbuilding Co. Ltd. has suffered from several cases of scuffing trouble on the cylinder liners. The causes of the trouble cases have been categorized to several items, and the appropriate measures have been applied in accordance with each mechanism. As the results of these activities to increase the margin for the sliding performance in the cylinder, Mitsui-MAN B&W engines of MC series have established very good cylinder performance.
Based on the above recent history, we think that more margin for sliding performance will be desired for furlher power up on the engines. We consider that one of the most promising candidates is spray-coated cylinder liner. The superior sliding performance of spray coating has been proven, for one example by the application on piston rings and cylinder liners in these years.
This paper describes our attitude and challenge for applying the coating on cylinder liners for 2 stroke crosshead diesel engines.
2. EXPERIENCES OF SPRAY-COATED CYLINDER LINERS
2.1 Service experience of Mitsui-ADD 4 stroke engine
Mitsui-ADD 4 stroke engines are applied with spray-coated cylinder liners from the beginning of their service operation, and they have been recording excellent cylinder performance with high anti-wear character and high bonding strength of coating. The engine specification and the wear rate data are shown in Table 1, and overhauled cylinder liner and piston rings are shown on Fig. 1 and Fig. 2.
Table 1 Mitsui-ADD 4 stroke Engine Spec. and Wear Rate Data
