RU2237564C2 - Insulating coating dismounting method - Google Patents

Abstract

FIELD: processes of assembling-disassembling metallic and non-metallic units, mainly procedures of dismounting insulating coatings in marine ships.

SUBSTANCE: method comprises steps of acting upon insulating layer in order to provide bending of layer and its tearing off metallic base; making through puncture in insulating layer; feeding through said puncture jet of water under pressure 120 - 170 MPa; forming between insulating layer and metallic base hydraulic wedge directed by its point to zone of joining insulating layer with metallic base.

EFFECT: simplified process of stripping coating from metallic base due to applying effort to joining zone of material at easily power supplying to joining zone, elimination of using strength cutting tool.

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Description

The claimed invention relates to the processing of products, in particular to the assembly, disassembly of metal, non-metallic assemblies and is intended primarily for the dismantling of insulating coatings on ships.

Various methods are known for solving this problem. For example, on May 10, 1999, an application for a patent of the Russian Federation for an invention was published under the name "Method for underwater hydrodynamic cleaning of ship hulls and a device for its implementation" (No. 98111015 from 06/18/98; IPC 63 V 59/08, 08 V 3 / 02). The method includes exposing the surface to be cleaned with a jet of water under pressure to ensure the occurrence of cavitation in the cleaning zone. The occurrence of cavitation is ensured by the simultaneous action of a stream of water and acoustic radiation on the surface being cleaned.

The disadvantage of this direction of solving the problem is environmental pollution by flying particles of material removed from the surface being cleaned. This is due to the fact that the working area is open.

The well-known "Method of removing plastics from the surfaces of products", which issued a patent of the Russian Federation No. 2060884 (application No. 93056071 from 12/21/93, IPC B 29 V 17/02).

The method relates to the regeneration of plastics and can be used, for example, to remove rubber attached to a metal surface. The method includes pre-heating the removed plastic, the heating being carried out with hot gas, and the place of heating is isolated from the environment.

The disadvantage of this method is the possibility of harmful emissions into the atmosphere, because thermal insulation protects against heat loss, but it is almost impossible to make it airtight in the field. In addition, the scope of the method is rather narrowly limited, due to the need for heaters, the complexity, and sometimes the impossibility of isolating the heating place. This applies, for example, to the disposal of nuclear submarines.

The well-known "Method of dismantling insulating coatings", which issued a patent of the Russian Federation No. 2107641 (application No. 96102349 dated 05.02.96, IPC 63 V 59/06).

The method is carried out by high-frequency thermal exposure of the adhesive layer between the coating and the metal surface below it. The thermal effect on the adhesive layer is produced from the metal side by induction heating in the high-frequency magnetic field of the inductor located on the coating side, with a certain range of field frequency, temperature and heating rate.

The disadvantage of this method is the possibility of harmful emissions into the environment, the effect of a magnetic field on personnel and equipment located near the place of work.

A known method of dismantling insulation coatings using a mechanical tool (UK application No. 2237186, IPC B 63 V 59/06, 1991, publ. 1993 in the abstract journal "Inventions of the World", No. 1, issue 47, VNIIPI) . With this method, the removal of the coating from the surface of the vessel is carried out using a rotating device equipped with a cleaning tool.

The disadvantages of the method are its great complexity and destruction of the coating itself, as well as the limited applicability of the method, due to the limited durability of the cutting tool.

The well-known "Method of separating the rubber layer from a metal base with a high coefficient of adhesion", which issued a patent of the Russian Federation No. 2105651 (application No. 96110540 from 05/27/96, IPC B 23 P 11/00, 19/00).

The essence of the known method consists in exposing the rubber layer (insulation coating). The impact is carried out by a tool in the form of a plate with a ledge. The plate is placed perpendicular to the separation surface in contact with the step surface with the end face of the rubber layer and the free surface of the latter adjacent to it. The tool is moved along the separation surface, ensuring the deformation of the rubber layer in the form of a wave, until it is separated from the metal base.

The disadvantage of this method is the difficulty of implementing it on surfaces having large areas, for example, for cleaning ship hulls. This is due to the fact that the width of the surface being cleaned in one pass is determined by the width of the tool, which is limited by the strength of its material. As the width of the tool increases, the load on it increases. In this case, it becomes necessary to increase the power of the tool drive and the strength of the tool holder. In addition, it is difficult to place the tool drive on the surface of the hull.

The closest analogue of the claimed invention is a method of tearing off the outer layer of a protective film described in the invention under the name “Method of protecting the underwater part of the ship’s hull”, for which RF patent No. 2021946 C1, IPC 7 V 63 V 59/04 was issued, published October 30, 1994 .

The method includes forming a closed cavity under a layer of a protective film (insulation coating) glued to the metal base (lower part of the ship’s hull), injecting water into it, acting on the film (coating), causing it to bend and detach from the base. Such an effect may be the gravity of adhering organics and / or the flow of water when the viscous resistance to the movement of the vessel due to fouling with a layer of organic matter exceeds the mechanical characteristics of the adhesive.

It is possible to use such adhesives that can “respond” to various influences (temperature, pressure, electric fields, adhesive solubility, etc.), which allows the layer to be torn off not only mechanically, but also as a result of the influence of these factors.

The method provides a convenient cleaning of the lower part of the hull from overgrown organics afloat.

However, the application of the known method for dismantling the insulation coating is associated with significant inconvenience. In particular, spontaneous separation of the coating may deprive the protection of a vessel that is still in operation. The opposite can happen when the vessel was sent for recycling and the coating did not come off, and it would be necessary to “drive” the vessel additionally until the coating was torn off or to find other ways to apply force to the coating to tear it off.

The problem that is solved by the claimed invention is to simplify and increase the convenience of cleaning technology.

The essence of the invention lies in the fact that in the method of dismantling the insulating coating act on the insulating layer, causing it to bend and tear from the metal base. A feature of the claimed invention is that for bending the insulation coating, a through puncture is performed in it, a jet of water is supplied through the puncture under a pressure of at least 120 MPa, a hydraulic wedge is formed between the layer and the metal base, directed by the tip to the junction of the insulation layer and the metal base.

The technical result, which determines the solution of the problem, is to simplify the application of force to the junction of the shared materials due to a more convenient supply of energy to this zone.

As a rule, the dismantling of ships is carried out near the coastal structures, so the water supply from the coastal communications will not cause difficulties. It is not difficult to place the installation for supplying water under pressure on a dismantled vessel, and to supply water to the working area through a pipeline. The pipeline may be of such a length as is necessary to treat the entire surface. It is also easy to provide for periodic transfers of the water supply unit if the pipeline is not long enough.

The presence in the claimed invention features that distinguish it from the prototype, allows us to consider it appropriate to the condition of "novelty."

New features (performing a through puncture in the insulating layer, supplying a jet of water through a puncture under a pressure of at least 120 MPa, the formation of a hydraulic wedge between the layer and the metal base of the wedge pointed to the junction of materials) were not detected in technical solutions of a similar purpose. On this basis, we can conclude that the claimed invention meets the condition of "inventive step".

The drawing shows the beginning of the separation of the insulating coating from the metal base.

EXAMPLE

The rubber (insulating) coating fixed with glue on the submarine’s hull (metal base) was removed. For this, a rubber coating 3 was pierced with a metal needle 1 in the form of a tube with a beveled end 2 until the end of the end 2 of the needle 1 was punched into the metal base 4. From the installation (not shown in the drawing) through a pipeline (not shown in the drawing) connected to the needle 1, and hole 5 of needle 1, high-pressure water was supplied to the puncture zone — the operating pressure of the pump in the installation was selected and maintained within 120-170 MPa.

Due to the braking pressure of the water jet in the zone of the needle 1, a hotbed of adhesive bond destruction was formed, a water bubble formed, and the coating was bent. As water arrived, the pressure in the bubble increased. After the pressure exceeded the tensile strength of the adhesive joint, a hydraulic wedge 6 was formed, directed by the tip to the junction of the materials. The hydraulic wedge 6 spread around a circle, the center of which was the needle 1, up to the butt welds (not shown) of the detachable sheet 3 with other sheets of rubber coating. The propagation speed was proportional to the backwater (intake) of water in the cavity of the wedge 6. The final size of the separation zone 3 of the coating was determined by a conditional circle with a radius of 0.2-0.3 m, limited by butt joints. When water (wedge tip 6) exits into the seam zone, water breakthrough occurs and growth of the wedge cavity 6 stops - a condition for stopping water supply. The separation time of the coating 3 in the indicated area was about 20 seconds. It was found that relative to the total surface of the coating sheet 3, the separation area was up to 80%. The total area of local sites on which the separation of coating 3 was performed was at least 10 m ² .

Even incomplete separation of the coating by the proposed method in combination with subsequent mechanical removal significantly simplifies and speeds up the process of removing the rubber coating from the submarine’s hull, making it more convenient, which was established during interagency tests of the technology developed on the basis of the claimed invention.

Thus, the information presented indicates the fulfillment of the following set of conditions when using the claimed invention:

- a tool embodying the inventive method in its implementation, is intended for processing products, mainly for the dismantling of insulating coatings on ships;

- for the proposed method in the form in which it is described in the claims, the possibility of its implementation using the means and methods described in the application and known prior to the priority date is confirmed.

Therefore, the claimed invention meets the condition of "industrial applicability".

Claims (1)

The method of dismantling the insulating coating, according to which they act on the insulating layer, causing the layer to bend and detach from the metal base, characterized in that a through puncture is performed in the insulating layer, a stream of water is supplied through the puncture under a pressure of 120-170 MPa, they are formed between the layer and the metal base hydraulic wedge directed by a tip to the junction of the insulating layer and the metal base.