Patent ID: 8632276

Claim:
A working apparatus for processing underwater bed areas of waterways comprising: a plurality of polygonal hollow pipes, each of said polygonal hollow pipes having an upper end and an outer wall, said polygonal hollow pipes being arranged in parallel side by side and at least substantially without gaps, said upper ends of said polygonal hollow pipes forming a horizontal, at least substantially flat working platform, said working platform having an outer edge; each of said polygonal hollow pipes having on its said outer wall at least one projection extending substantially horizontally and a corresponding plug-on aperture, said plug-on aperture being positioned in said outer wall, said projection having an outer end and a flange disposed on said outer end, said flange extending substantially vertically, a slot being positioned immediately above said corresponding plug-on aperture, said slot running vertically and extending to said upper end of said polygonal hollow pipe; said plug-on aperture being disposed further away from said upper end of said polygonal hollow pipe than said projection, said flange being of greater horizontal dimensions than said slot; and neighbouring said polygonal hollow pipes being in engagement with one another via a respective said projection on one of said polygonal hollow pipes with a corresponding slot in another of said polygonal hollow pipes such that said polygonal hollow pipes cannot be moved relative to one another in the horizontal direction and only at said outer edge of said working platform can at least one said polygonal hollow pipe be pulled out individually in the vertically upward direction.