Abstract: The invention relates to the rapid exchange of a detachably fastened part such as the suction head (3) of the suction pipe (2) of a hopper suction dredge (1) or a part of the suction head by a rapid-action coupling (7,8) and by a device (10,12,13,14,15) on deck (1) which can grip the part (3) while it is still fastened, can remove it after uncoupling and move the other part (16) towards the coupling (7,8) which device preferably comprises a number of arms (12,13) in fixed position relative to one another and rotatable about a horizontal axis (11) each arm (12,13) having a device (14,15) for carrying and releasing a suction head (3,16).