MODIFICATION OF DREDGERS, A CRAZY IDEA OR NOT?

摘要

There can be multiple reasons for modification or conversion of dredgers and all related equipment.Today we see a shortage of dredging material. Due to the large dredging works in the Persian Gulf and other areas.the demand for special equipment is high and not all existing equipment has sufficient capacity or quality to fit the bill. In addition most yards are fully booked for the coming years, so modification is sometimes the only alternative.Modifying equipment might cause problems: 1. How is the technical condition? 2. Which drawings are available? 3. Did new rules become effective? 4. How about efficiency and economical status? For most types of equipment there are a lot of possible modifications. For trailing suction hopper dredgers the hopper capacity can be increased as well as the dredging depth. The loading and unloading process can be improved, etc. For cutter suction dredgers the cutter power and all relevant items can be upgraded, the cutter depth can be increased or just minimized. The swing length and dredging process can be improved by installing a spud carrier system, etc. Existing equipment can be converted into other systems like modifying a split barge into a split hopper dredger, a bucket dredger into slope trimmer, a cutter dredger into deep suction dredger, a tug into a bed leveller etc. Also merchant vessels can be converted into dredging vessels like a naval supply vessel into an aggregate dredger, a module carrier into deep stone dumper/deep dredger, a work vessel into a water injection dredger, etc.In this paper a number of projects will be presented, realized in the last ten years.It can be concluded from these examples that there are very often new possibilities for existing equipment, even when they are of older age.