Narrow Results

In order to enhance the corrosion resistance of mooring chain, the composite coatings are carried out on the surface of 22MnCrNiMo steel for mooring chain by double-pulsed electrodeposition technology using centrifugal force in the rotating device. The microstructure and anti-corrosion performance of the composite coatings have been investigated experimentally. This paper mainly focuses on the experimental work to determine the structural characteristics and corrosion resistance of composite coatings in the presence of nano-SiC. The results show that the presence of nano-SiC has a significant effect on the preparation of composite coating during the process. The surface of the coating becomes compact and smooth at a moderate concentration of nano-SiC particles. Furthermore, the best corrosion resistance of the composite coatings can be obtained when the concentration of nano-SiC particles is 2.0g.L${}^{-1}$ after salt spray treatment.

Mooring systems experience high tidal waves, storms and harsh environmental conditions. Therefore, ensuring the integrity of mooring chain is important. The aim of the work reported in this paper is to develop a robotic system that performs in-service non-destructive testing of mooring chains. The inspection system is an autonomous device that operates in air as well as underwater. The permanent magnet adhesion crawler robot developed can climb mooring chains at a speed of 42cm/minute with a pay load of 50N. FEA study of the magnetic adhesion module, structural analysis, prototyping and testing of the robot is presented in this paper.

When a mooring chain is broken due to a high wave, a moored ship can be drifted and stranded. In order to attenuate damages to facilities in a port, it is important to predict the movement of a moored floating object driven by high waves. In some previous numerical methods for this kind of prediction, it was difficult to simulate a floating object appropriately under high waves including a fragmentation and a coalescence of water like a breaking wave. On the other hand, the particle method is suitable for analysis under such a complicated water surface change. Therefore, in this study, a simulation model of moored buoy based on a particle method is developed.