Patent EA-001832-B1 (EA)
Title: Method for inverting the upwardly convex configuration of the bottom of a liquid product storage tank
Inventor: WITTER ALDYR
IPC: E04H7/06
Filed: 1998-09-08
Abstract: 1. Method for inverting the upwardly convex configuration of the bottom of a liquid-product storage tank having at least one cleaning port, comprising the following stages: - first arranging on the bottom (5) a plurality of containment formwork units (18) distributed over the surface of the bottom except in at least one section extending from the centre of the tank bottom (5) to a region at its periphery in front of a said cleaning port (4), which units form containment areas for the placing of a hardenable material having plastic properties; - then placing in the containment areas formed by the containment formwork (18) a hardenable material which has plastic properties and which has dimensions such that, other than in said at least one section extending from the tank bottom centre to its periphery, the quantity of said hardenable material which has to be placed on the containment areas increases with increasing radial distance from the centre of the conventional bottom (5); and converting said at least one section into a drainage gutter (9) which has a ramp (10) whose gradient is sufficient to encourage flow of the undesirable liquids and sediments to the region in front of the cleaning port (4) from which they can more easily be drained off. 2. Method according to Claim 1, characterized in that the containment formwork (18) extends radially over the conventional bottom (5) of the liquid-product storage tank (1). 3. Method according to Claim 1, characterized in that the conventional bottom (5) is coated with a layer of sealing material. 4. Method according to any one of claims 1 to 3, characterized in that a ramp (10) is formed by applying on the conventional bottom a conic layer of the hardendeble plastic material having plastic properties so as to change the inclination angle of the drainage gutter bottom (9) respective to the inclination angle of the conventional tank bottom 5. Method according to Claim 4, characterized by the step of applying a coating of sealing material to the part of the conventional bottom (5) which forms the ramp (10). 6. Method according to any one of claims 1 to 3, characterized by the step of applying said hardenable plastic material to said at least one section extending from the centre of the tank bottom to its periphery, in a configuration such that the surface of the hardened material in said at least one section is inclined downwardly from the centre of the tank bottom towards the tank periphery with an inclination which differs from that of the conventional tank bottom before conversion. 7. Method according to claim 6, characterised by the step of applying a coating of sealing material to the surface of said hardened material in said at least one section. 8. Method according to any one of Claims 1 to 3 characterized in that the containment formwork (18) is constructed such that part of the top which is at the level of the surface of the layer of the hardenable plastic material can be removed after the applied material has hardened; and in that sealing material is applied to the interior of the gaps formed between the adjacent bodies of the already-hardened plastic material. 9. Method according to claim 1 or 2, characterized by coating with a sealing material the new bottom (7) formed by the application of hardenable plastic material, the side walls of said drainage gutter (9) and the pan of the conventional bottom (5) forming the ramp (10), of the drainage gutter.