Double bottom hull for tank ship
AssigneeSaudi Arabian Oil Company
InventorsFouad Abdul Karim Al-Rammah, Thomas J. Scott
Life of this patent
Estimating the term…
Abstract
A new tank ship, or an older ship which might not otherwise be economically retrofitted to comply with current regulations, is provided with a double hull requiring essentially no internal steel structural support by distributing and compacting sand in the bottom of the tank or cargo hold, applying a layer of reinforced concrete to the sand, laying steel plates on the surface of the cured concrete and welding the abutting edges of the plates to the hull, interior bulkheads, and to each other, to form a second fluid-tight bottom in the tank. The construction method can be used to retrofit older tankers to comply with Regulation 13G of MARPOL.
Claims29
A method of providing a second bottom to a cargo hold in a steel hull ship, said second bottom being supported without a steel structure, the method comprising:
- a) applying a first layer of sand to the bottom of the ship's cargo hold over an area that is to be covered by a second bottom;
- b) compacting the first layer of sand;
- c) applying one or more additional layers of sand to the first layer of compacted sand;
- d) separately compacting each of the one or more additional layers of sand after the layer has been applied;
- e) applying a layer of reinforced concrete to the uppermost layer of compacted sand;
- f) placing one or more steel plates on top of the cured layer of reinforced concrete and in abutting relationship with the side walls of the cargo hold, and/or with each other;
- and
- g) welding the one or more steel plates to the side walls of the cargo hold, and/or to each other in fluid-tight relation, to thereby provide a continuous second bottom to the cargo hold capable of supporting and retaining cargo placed in the cargo hold.
A double bottom construction for a steel hull ship, the double bottom extending from the interior surface of the hull to interior bulkheads, comprising:
- a) a load-bearing layer of compacted sand in contact with the hull of the ship;
- b) a layer of poured-in-place reinforced concrete on the surface of the layer of compacted sand;
- c) steel plating in contact with the surface of the cured layer of reinforced concrete and in close-fitting relation with the hull and bulkheads;
- d) weldments joining the steel plating to the hull and bulkheads in fluid-tight relation, whereby a second bearing bottom is rigidly supported without an underlying steel supporting structure.
The invention of 21 which complies with Regulation 13G of MARPOL.
Dependencies are inferred from the claim text.