Plastic Main Propellers Making Debut
Japanese classification society ClassNK and Nakashima Propeller Co., Ltd., have installed the world’s first carbon fiber reinforced plastic (CFRP) propeller on a main propulsion system of a merchant vessel.
The CFRP propeller was installed on the Taiko Maru, a domestic 499 GT chemical tanker owned by Sowa Kaiun YK by Marugame-based Koa industry Co., Ltd. in May 2014.
The CFRP propeller installed on the vessel was developed and produced by Nakashima Propeller Co., Ltd., with support from ClassNK, which granted approval for the design and manufacturing process of the CFRP propeller, as well as provided research and funding support for the project as part of the ClassNK Joint R&D for Industry Program.
Despite its ultra-lightweight composition, CFRP exhibits the same, if not superior strength, to the aluminum-bronze composite materials used in conventional propellers, according to ClassNK. Due to the light weight of the propeller, propeller shafts can be manufactured with smaller diameters, contributing to a significant reduction in weight and fuel costs.
The Taiko Maru had already been fitted with CFRP propellers in its side thrusters in September 2012. Based on their successful performance, Sowa Kaiun YK made the decision to extend the use of the CFRP propeller technology to its main propulsion system, making the vessel the first in the world to use a CFRP for its main propulsion system, Class NK reports.
During sea trials the CFRP required 9% less horsepower to operate compared to conventional aluminum-bronze propellers, and Class NK believes that expansion of their use on merchant vessels is expected to contribute to better fuel economy and greater efficiency in operations.
Class NK has also disclosed that it will embark on a joint research project together with Daihatsu Diesel Mfg. Co., Ltd. to test the extensibility of condition based monitoring system and automatic diagnostic system “ClassNK CMAXS LC-A” for auxiliary diesel engines manufactured by Daihatsu Diesel Mfg. Co., Ltd.
The aim of this joint project is to test the extensibility of “ClassNK CMAXS LC-A”, a cloud-based machinery maintenance system that uses software to analyse sensor data obtained in the engine room for automatic condition diagnoses, and to detect any early signs of damage to auxiliary equipment.
According to Class NK, the system will be able to show the condition of a wide variety of equipment in real-time and through the optimisation of scheduled overhaul intervals, and it will subsequently improve the life-cycle costs and enhance the safety of ship operations. The project is scheduled to continue in October 2015.