RU2364612C2 - Method for manufacturing of heat insulation coating and composite material for its realisation - Google Patents

Abstract

FIELD: construction.

SUBSTANCE: invention is related to heat insulation coats. Method is described for production of heat insulation coat of item element, which consists in application of composite material on surface of element in the form of suspension of basalt canvas fragments in water gel and thermal treatment of applied material. Composite material is also described for production of heat insulation coat of item element. Composite material contains mixture of filler and binder in the form of suspension of basalt canvas fragments in water gel, besides, fragments of basalt canvas are contained in amount of 10.7-11.7 wt %, and water gel in amount of 88.3-89.3 wt %, besides, water gel includes guar gum in amount of 0.490-0.492 wt %, surface active substance in amount of 0.047-0.049 wt % and water - rest.

EFFECT: suggested method makes it possible to provide for production of highly efficient and strong heat insulation coating of large-size elements of item with vertical and downrun open surfaces without additional fastening of this coating.

6 cl, 4 dwg, 2 ex

Description

The invention relates to the field of high temperature technology, in particular to coatings in need of thermal insulation of machine elements.

A known method of manufacturing a heat-insulating coating of a pipe, which consists in placing concentrically a pipe with a gap of a thin-walled shell equipped with stiffeners, and filling the annular cavity between the pipe and the shell with a heat-insulating material (patent RU No. 2200897, class F16L 59/00, published on March 20, 2003) . The known method provides thermal insulation of pipes intended for underground installation. The method cannot be used for products of a more complex geometric shape, as well as in the field of high-temperature technology, since in the presence of vibrational loads it does not provide sufficient strength of the resulting coating.

Closest to the claimed one is a known method of filling a cavity with an insulating material in a product formed by the surfaces of the constituent elements of the product, which consists in applying a composite material to the surface of at least one element. As a composite material, a suspension of a heat-insulating filler in an organic water-containing binder is used, in particular, a suspension of fragments of basalt canvas in an aqueous gel (application RU No. 2005131747, class C04B 38/08, according to which a decision was made to grant a patent of the Russian Federation, publ. 04/20/2007) . In this method, the applied composite material after the assembly of the product is limited to the surfaces of its elements, while it is not necessary to ensure adhesion of the material to the surface and the mechanical strength of the coating. For the manufacture of heat-insulating coatings on the open surfaces of product elements, this method is unsuitable.

The technical result of the claimed invention is the creation of a method that allows the manufacture of a highly effective and durable heat-insulating coating of product elements, including large ones, with vertical and downward facing open surfaces without additional fasteners for this coating.

The technical result is achieved in a method of manufacturing a heat-insulating coating of an element of an article, which consists in applying a composite of basalt canvas fragments in an aqueous gel to a surface of an element of an element and heat treating the applied material, using a suspension as a composite material in the following ratio, wt.%:

fragments of basalt canvas 10.7-11.7 water gel 88.3-89.3

wherein the aqueous gel includes fresh water, guar gum and a surfactant in the following ratio of components, wt.%:

guar gum 0.490-0.492 surfactant substance 0,047-0,049 water rest

To obtain a suspension, fragments of basalt canvas with a portion of an aqueous gel may be mixed in the amount of from 0.7 to 0.75 wt.% Aqueous gel, and then the resulting mass should be diluted with the remaining portion of the aqueous gel, which increases the uniformity of the suspension.

Composite material can be applied in layers and after applying each layer to dry, which increases the strength of the coating with an increase in its total thickness.

Drying can be carried out with stepwise heating to a temperature not exceeding 300 ° C, which increases the strength of the coating.

An additional layer of fiberglass based on polymer glue can be applied to the coating surface, which provides protection against external mechanical damage.

It is essential that the suspension (composite material) contains basalt canvas in the declared quantities, and the canvas size can be different depending on the configuration of the surface of the product and the scale factor of the product, and in the finished suspension depending on time and mixing parameters, which is also determined by the configuration of the product. However, the optimal result is achieved when using a homogeneous mixture of fragments of basalt canvas and water gel.

Known heat-insulating material, which is a basalt material and / or vermiculite (application RU No. 2001127628, CL EV 17/00, publ. 07.27.2003). High temperature and vibration exclude the use of organic heat-insulating materials with low heat resistance and brittle heat-resistant ceramic materials, as well as dispersed ones, which undergo vibration during vibration. Remaining heat-insulating materials from mineral fibers - cotton, canvas, mat. Their use in the initial state (with low density) causes many complications associated with the manufacture of patterns, their compaction, fixing on the surface and the manufacture of a protective coating.

Known is a composite material for filling a cavity in an article containing a mixture of a filler and a binder in the form of a suspension of fragments of basalt canvas in an aqueous gel (application RU No. 2005131747, class С04В 38/08, according to which a decision was made to grant a patent of the Russian Federation, published on 04/20/2007 ) This material is designed to fill cavities and after assembly of the product is limited to the surfaces of its elements. In this case, it is not necessary to ensure adhesion of the material to the surface and the mechanical strength of the coating. This material is unsuitable for the manufacture of a heat-insulating coating on open vertical and downward surfaces of the product element.

The technical result of the claimed invention is the creation of a composite material for the manufacture of a highly effective and durable heat-insulating coating of product elements, including large ones, with vertical and downward facing open surfaces without additional fasteners for this coating.

The technical result is achieved in a composite material for the manufacture of a heat-insulating coating of an element of an article containing a mixture of filler and a binder in the form of a suspension of fragments of basalt canvas in an aqueous gel, using a suspension in the following ratio of components, wt.%:

fragments of basalt canvas 10.7-11.7 water gel 88.3-89.3

wherein the aqueous gel includes fresh water, guar gum and a surfactant in the following ratio of components, wt.%:

guar gum 0.490-0.492 surfactant substance 0,047-0,049 water rest

Any surfactant classes that can be used, for example, in the production of detergents, oil and gas, textile, chemical industries, construction, etc. (sulfonol-P, cocamidopropylbetaine, monoethanolamide, diethanolamide, sodium lauryl sulfate and etc.).

The invention is illustrated by examples of the method, the composition of the composite material and figure 1-4, where:

figure 1 shows a plate with a heat-insulating coating;

figure 2 is a side view of the plate;

figure 3 is a model of the pipe;

figure 4 is a side view of the model pipe.

Composite material and the coating itself are made as follows.

As a composite material, a suspension is used in the following ratio of components, wt.%:

fragments of basalt canvas 10.7-11.7 water gel 88.3-89.3

wherein the aqueous gel includes fresh water, guar gum and a surfactant in the following ratio of components, wt.%:

guar gum 0.490-0.492 surfactant substance 0,047-0,049 water rest

For the manufacture of an aqueous gel, the required amount of water is taken into the container, and with active stirring of the water with a frame screw mixer, a gel sample (guar gum) is loaded into the container by scattering. After stirring until a gel with a uniform consistency is kept for 30 minutes to one hour. With active stirring of the gel, a surfactant is gradually added to the container and stirring is continued for 3 to 10 minutes.

From 0.7 to 0.75 wt.%, A separate container is taken from the gel to make a suspension. Fragments of basalt canvas are portionwise loaded into a container with the remaining part of the aqueous gel, followed by vigorous stirring after each portion until a homogeneous mixture is obtained. Each portion of fragments of basalt canvas is from 1/7 to 1/10 of the total canvas volume. After loading the last portion of the canvas fragments, mixing is continued until a dense fine-grained (2-3 mm) mass is homogeneous in consistency. A selected portion of the aqueous gel is introduced into the prepared mass, followed by stirring until a dense plastic mass — a composite material — is homogeneous in consistency.

The coating is made by applying a composite material to the surface of the product element in layers and after applying each layer, drying is carried out, which is carried out by step heating to a temperature not exceeding 300 ° C. An additional layer of fiberglass based on polymer glue is applied to the coating surface.

Example 1

The manufacture of the coating on a flat plate 1 of steel on the vertical and facing down surfaces (Fig.1, 2). Used composite material in the following ratio of components, wt.%:

fragments of basalt canvas 11,2 water gel 88.8

The composition of the aqueous gel, wt.%:

fresh water 99,461 guar gum 0.491 monoethanolamide 0,048

To obtain a suspension, 0.7 wt.% Aqueous gel was taken, averaged size 25 mm × 25 mm × 25 mm was mixed with basalt canvas fragments and diluted with the remaining part of the aqueous gel.

The composite material was applied to the surface of the plate 1 in two sections 2 and 3. Section 2, where the surface is degreased, and section 3, where the surface is coated with KO-814 varnish to protect against corrosion. The plate size is 210 × 360 mm, the width of sections 2 and 3 is 90 mm. The thickness t of the applied layer is 30 mm. Within 60 minutes of exposure, the layer is held on the surface of the plate both when it is vertically located and when the surface is facing down (on the "ceiling" surface).

Drying was carried out by heating stepwise to a temperature of 300 ° C. After drying, the layer is firmly held on the plate.

A second layer of composite material was applied, and the total thickness t was 50 mm. The layer is held on vertical and downward facing surfaces.

They carried out drying, producing stepwise heating to 250 ° C. The coating is firmly bonded to the steel plate 1. The coating density is 0.13 g / cm ³ .

Example 2

The manufacture of insulating coatings on the model of the pipe (Fig.3, 4).

Model - pipe 4 of rolled black steel without traces of corrosion and scale. A surface with a low roughness. Outer diameter 252.5 mm, length 268 mm, wall thickness 1.5 mm. On the outer surface, a belt of varnish KO-814 in one layer. The surface of the varnish is smooth.

The pipe section on the surface of which a heat-insulating coating was made is bounded by two polyvinyl chloride walls 5 and 6 with holes in the center corresponding to the size of the pipe. To fix the walls 5 and 6, the cams-clamps are welded to the pipe 7. The surface area bounded by the walls 5 and 6 is varnished with KO-814. Thermal insulation coating 8 was made by applying two layers of composite material.

Used composite material in the following ratio of components, wt.%:

fragments of basalt canvas 11,2 water gel 88.8

The composition of the aqueous gel, wt.%:

fresh water 99,461 guar gum 0.491 diethanolamide 0,048

The size of the basalt canvas fragments is 50 mm × 50 mm × 50 mm. The thickness t of each of the layers was 20-30 mm. The material was applied manually by pressing the first layer with pieces to a steel surface, and the second to the surface of the dry 1st layer. The 1st layer was dried by step heating to 250 ° C. Drying was carried out with the walls 5 and 6 removed while the pipe 4 was in vertical position. The second layer was formed with round walls 5 and 6 providing a coating thickness of 50 mm. The second layer was dried at a temperature of 70 ° C to a state that allows you to remove the walls, then with stepwise heating to 200 ° C.

An additional layer of fiberglass based on a polymer adhesive was applied to the coating surface 8. KS-Universal inorganic liquid-glass adhesive, which is a paste-like adhesive (mastic), was applied to the surface of coating 8, T-11 grade fiberglass was laid and an additional KS-Universal adhesive was applied on top. Got a hard coating that can withstand moderate external loads.

The invention allows for effective thermal insulation of product elements, including large ones, as well as those subject to high-frequency vibration loads.

To achieve the claimed technical result, glue of any composition and chemical nature can be used, since its main task is to impregnate the fabric (basalt canvas), which prevents its destruction during operation. For example, these may be the following adhesives belonging to different classes - VK-20 (based on polyurethane), K-300, K-400, "Octopus", "88", "KS-Universal", starch glue, etc. .d.

Claims (6)

1. A method of manufacturing a heat-insulating coating of an element of an article, which consists in applying a composite of basalt canvas fragments in an aqueous gel to a surface of an element of an element and heat treating the applied material, characterized in that a suspension is used as a composite material in the following ratio of components, wt.%:
fragments of basalt canvas 10.7-11.7 water gel 88.3-89.3
wherein the aqueous gel includes fresh water, guar gum and a surfactant in the following ratio of components, wt.%:
guar gum 0.490-0.492 surface-active substance 0,047-0,049 water rest 2. The method according to claim 1, characterized in that in order to obtain a suspension, fragments of basalt canvas are first mixed with part of the aqueous gel in an amount of from 0.7 to 0.75 wt.%, After which the resulting mass is diluted with the remaining part of the aqueous gel. 3. The method according to claim 1, characterized in that the composite material is applied in layers and after applying each layer, drying is performed. 4. The method according to claim 3, characterized in that the drying is carried out by step heating to a temperature not exceeding 300 ° C. 5. The method according to claim 1, characterized in that an additional layer of fiberglass based on polymer glue is applied to the coating surface. 6. A composite material for the manufacture of a heat-insulating coating of an element of an article containing a mixture of a filler and a binder in the form of a suspension of fragments of basalt canvas in an aqueous gel, characterized in that the suspension is used in the following ratio of components, wt.%:
fragments of basalt canvas 10.7-11.7 water gel 88.3-89.3
wherein the aqueous gel includes fresh water, guar gum and a surfactant in the following ratio of components, wt.%:
guar gum 0.490-0.492 surface-active substance 0,047-0,049 water rest

Images