High-power fibre laser cleaning for green shipbuilding

Abstract

Blasting techniques in shipbuilding and ship repair have been developed for surface preparation of steel to a standard equivalent to SA2.5 as defined by ISO Standard 8501. The usage of consuma-bles, such as abrasive materials, air and water, constitutes a recurring cost in these processes. When blasting work is carried out in the open space, such as during a dry docking, abrasive blasting gen-erates a lot of dusts which in turn pollutes the environment with consequential social and economi-cal costs. Laser blasting or laser cleaning, which has not been introduced commercially in shipbuild-ing and ship repair, offers an alternative for green manufacturing and green repairs. Laser cleaning has significant advantages on these issues over the conventional blasting techniques. It is a well-controlled process with unique properties, such as precise treatment, high selectivity, and high flexi-bility. A cleaning technique using a high-power fibre laser is developed for the surface preparation of steel. Fibre laser has advantages of compact system, automation capability, and low maintenance cost. We report the laser cleaning results using a 500-W pulsed high-power fibre laser. The laser cleaning is able to meet the SA 2.5 requirements of blast cleaning as described in the International Organization for Standardization (ISO) standard 8501.