EA033664B1 - Molding of a foamed glass product with an outer protective crust - Google Patents

Abstract

A method of producing mold casted, sealed foam glass components with an outer protective crust, as insulation and fire protection for pipes and structural components, building panels and other uses. According to one aspect the method is based on mixing a reactive ingredient (foaming agent) with one or more oxidants, and then adding this into crushed or milled glass, blending it, and then this is again added into a closed mold/casting die made from titanium, graphite or another suitable material, and heated until the glass melts and the reactive ingredient and the oxidant react and decompose and produce bubbles of gas in the melted mixture.

Description

Technical field

The invention relates to foamed glass, in particular to a molded molded foamed glass product in the form of pipe insulation, in particular to a method for molded foam glass for prefabricated pipe insulation with a protective surface layer.

State of the art

Foamed glass is traditionally obtained by mixing crushed or crushed glass with one or more foaming agents, for example coal, as the main reaction ingredient in an open casting mold of heat-resistant steel or other heat-resistant material. When heated, the mixture expands with the formation of foamed glass. After this, the foamed glass is removed from the open casting mold and cut into blocks, which are subsequently further cut into desired shapes, for example, shapes intended for use as pipe insulation.

However, the traditional method has a number of the following disadvantages.

The traditional method of producing foamed glass products, in particular profiles for pipe insulation, is a laborious process, and therefore the cost to the end user is high.

On the outer surface of the profiles obtained in the traditional way, open pores are formed due to block cutting.

In addition to this, open pores appear on all surfaces of the cut, no matter what shape the final product has. As a result of this, a final product is obtained having sharp edges, which leads to increased friction in the pipe sections with which it is in contact. Open pores on the surface are directly exposed to moisture, which causes the surface to absorb water.

In addition, if the porous structure of traditional foamed glass obtained using coal as the main reaction ingredients is disturbed, small amounts of SO _{2 are released} , which, when reacted with water, and especially with salt water, increases the risk of corrosion under insulation (CUI, corrosion under insulation) due to electrochemical corrosion.

In addition, foamed glass made using coal as the main reaction ingredients is electrically conductive due to its high carbon content. Together, friction, water and electrical conductivity significantly increase the risk of pipe corrosion under insulation (CUI). In addition, in cases where foamed glass is used as protection against fire, carbon residues along with chemical energy will contribute to the fire scenario - and thereby reduce the fire resistance of insulation.

In addition, foamed glass obtained in the traditional way has a relatively low compression resistance (600 kPa), which limits the fineness of the profiles of insulating products that can be made of foamed glass without breaking it. In addition, foamed glass obtained in the traditional way will emit sulfur upon fragmentation, for example, due to vibration or direct pressure. This released sulfur when interacting with available moisture will lead to a change in pH. As a result, in direct contact with the pipes, the risk of CUI is significantly increased.

SUMMARY OF THE INVENTION

The present invention relates to a method for manufacturing molded molded sealed foamed glass components with a protective surface layer for use as insulation and fire protection of pipes and structural elements, building panels and other applications. According to one aspect, the method is based on mixing a reaction ingredient (blowing agent) with one or more oxidizing agents, then adding it to a broken or ground glass, homogenizing the mixture and then adding it to a closed mold / die made of titanium, graphite or another suitable material, and subsequent heating so that the glass melts, and the reaction ingredient and oxidizing agent react and decompose with the release of gas bubbles in the molten mixture. The method is based on mixing the calculated amount of the reaction mixture (blowing agent + oxidizing agents) with broken / ground glass, loading the mixture into a closed mold / casting matrix (made of a material such as titanium, graphite, ceramic or a metal alloy) with suitable heat resistance and properties expanding and heating the mold so that the glass melts, and the reaction ingredients emit gas bubbles, forming foam material of the required density and mechanical strength.

In one aspect, the reaction ingredient is SiC, and the oxidizing agent is MnO ₂ , which react to form CO ₂ bubbles.

According to another aspect, the reaction ingredient is Si ₃ N., or AIN, and the oxidizing agent is MnO ₂ which react to form N2 bubbles. In this case, the following reaction equations apply:

- 1,033664

1½ Si ₃ N ₄ + 3MnO ₂ - + _^3/2 SiO ₂ + 3MnO + N ₂

2AIN + 3MnO ₂ - + AI ₂ O ₃ + 3MnO + N ₂

According to another aspect, as the molar ratio of MnO ₂ with Si ₃ N ₄ or with AIN increases, a small amount of O ₂ bubbles will be released in addition to N2 bubbles, increasing the size of the bubbles and decreasing the density of the product.

According to one aspect, the reaction ingredient AIN has a fractional size of from 0.5 to 12 microns and can be from 0 to 15 wt.% The mixture.

In one aspect, the SiC reaction ingredient has a fractional size of from 3 to 40 microns and can range from 0 to 15 wt.% Of the mixture.

In one aspect, the ground glass has a fractional size of from 0.001 to 1.6 mm, preferably from 0.001 to 0.7 mm.

When used in this context, it should be understood that the ranges also express intermediate ranges, as if they were expressed in a special way. For example, a range of 0-15 will also include ranges such as 1-14, 1-13, 1-12, 2-14, 2-13, and so on.

A mold / die for casting, according to one aspect, is intended to produce a semi-cylindrical pipe insulation profile adapted to a particular pipe size or shape. The size and / or design of the profile can, however, be varied to obtain prefabricated profiles of different shapes for various applications, for example for building panels.

The amount of finely ground glass and the blowing agent is selected for the internal volume of the mold / die, so that the amount of foamed glass after heating and expansion is at least equal to that in the die. For example, in the case of a mold with an internal volume of 8 l and a desired density of 200 kg / m ^3, 1.6 kg of the glass mixture is loaded into the mold before heating. Preferably, the expansion of the foamed glass inside the closed mold will result in a positive (over) pressure inside the mold / die for casting in the range from just above atmospheric pressure to 3 bar above atmospheric pressure (in this context, expressed as from 0 to 3 bar), according to one aspect, from 1 to 3 bar and according to another aspect from 2 to 3 bar. All excess foamed glass can be diverted / blown through a narrow overflow channel, for example, through an opening or slot located in the upper part of the matrix. The size of the channel will be determined by the viscosity of the foamed glass at a specific operating temperature and the required internal pressure in the mold, for example, an overflow channel 1 mm high x 600 mm wide and 5 mm deep will be able to hold glass foam at a temperature of 880 ° C at 1 bar.

The casting matrix is closed and introduced into the heating zone, where it is heated to a temperature, usually in the range from 750 to 1000 ° C, depending on the choice of reaction ingredients and the required internal pressure created by the viscosity and size of the overflow channel. The heat source may consist of heat radiation, heating by air flow, induction heating, or other suitable indirect heat source, such as gas.

During the melting process, the die can be rotated so that the foamed glass is better distributed within the die.

The principle of operation of the overflow channel is that it has a configuration of the cross-sectional area (expressed as length times width) and depth (usually equal to wall thickness), which together define a pressure and viscosity-dependent barrier that can hold back foam inside the mold cavity within a given pressure drop - for any given viscosity (determined by the temperature for each specific glass formula and additives). If the pressure inside the mold exceeds this limit, the channel will act as a safety valve, releasing excess foam before the excess pressure can destroy the mold.

However, the channel is preferably narrow enough to allow a slight increase in pressure (at least 3 bar) relative to atmospheric - in order to provide an excess of pressure, useful to prevent component shrinkage during cooling, and thereby ensure dimensional stability.

Pressure build-up begins when expanding foam displaces all air from the mold cavity, and further expansion is not allowed as long as the pressure is high enough to displace the foam through the overflow channel. The degree of expansion and increase in pressure is given by the quantity and composition of the mixture of glass raw materials and reaction additives. The limiting pressure (at which further expansion will occur due to the displacement of the foam through the channel and preventing further pressure buildup) is determined by the geometric shape of the channel (cross section vs. (versus versus) depth) and the viscosity of the glass formula depending on temperature (depending on additives) . After a sufficient volume of foam is removed through the channel, the pressure drops to a value slightly below the displacement pressure - and further displacement does not occur until the pressure reaches the limit value again.

This feature provides the advantage that there is no need to worry about overflowing the mold — since any excess material will be removed through the overflow channel. In this case, the internal pressure in the foam can be maintained at a high and stable level during the reaction phase, providing dimensional stability by preventing shrinkage and deformation during the cooling phase. Adjustable overpressure in the reaction phase also contributes to a more predictable and uniform distribution of pore sizes in the foam.

When the foaming process is almost complete, and when gas bubbles form and expand to their desired size, the foamed glass will completely fill the die. The casting matrix is slowly cooled to a temperature at which the viscosity is high enough to stabilize the porous structure of the component and limit further shrinkage or deformation in a manner similar to metallurgical annealing.

The mold is then cooled even further to a temperature at which the glass foam becomes rigid enough to be removed from the mold without being damaged in a manner known to the person skilled in the art of glass manufacturing.

The fact that the foamed glass expands inside the closed die to achieve a predetermined size and shape identical to the final product makes it unnecessary to trim and refine the foamed glass half-cylinder before use.

When the foamed glass expands, the pores directly in contact with the walls of the matrix are compressed, making the walls of the outer pores thicker, and the foamed glass profile acquires a smooth and substantially sealed surface layer. This sealed outer surface essentially forms a sealed surface layer, almost a glass surface, where the pores directly from the inside of the surface layer are intact. This creates a smooth surface with low friction, that is, more sparing for the structure to be further insulated. Since the surface layer is airtight, the profile does not absorb moisture into the surface. Combined with the low conductivity of the product, this significantly reduces the risk of CUI.

The advantage of the method according to the invention is that the reaction is essentially chemically neutral, during which only gaseous N ₂ or CO _{2 is released} together with small amounts of O ₂ , which significantly reduces the risk of pipe corrosion compared to traditionally obtained insulation profiles from foamed glass made using coal as a reaction ingredient, where a small portion of SO ₂ is released and mixed with water in case of damage to the porous surface structure.

Another advantage of the invention is that tests carried out using a microwave scanner show that the product is transparent when scanned by microwaves and, therefore, is suitable for detecting moisture in insulation and corrosion under insulation at an early stage using microwave scanning. The specified scan can be carried out in the longitudinal direction of the pipe and is a non-destructive method. Foamed glass, obtained in the traditional way, contains significant amounts of unburned carbon and, therefore, is opaque when microwave scanning. As a result, scanning of insulating half-cylinders for moisture based on microwaves is impossible, and it is also impossible to determine CUI at an early stage without inspection based on a destructive method.

A brief description of the graphic materials

The invention will now be described with reference to drawings, in which FIG. 1 is a perspective view of a semicircular foamed glass product;

FIG. 2 is a cross section of a semicircular foamed glass product with a beveled edge;

FIG. 3 is a cross-sectional view of a semicircular foamed glass product with a seal groove;

FIG. 4 is a perspective view of a mold for a semicircular foamed glass product;

FIG. 5A and B are a cross-sectional view of a mold;

FIG. 6 is a perspective view of a lower semicircular profile;

FIG. 7 is a perspective view of an upper semicircular profile;

FIG. 8 is a cross section of the lower leaf of a mold filled with a glass mixture;

FIG. 9 is a perspective view of a mold for a semicircular foamed glass product with a glass mixture distributed along its length;

FIG. 10 is a cross-sectional view of a semicircular mold;

FIG. 11A, B and C are detailed views of a locking mechanism;

FIG. 12A and B illustrate a T-shaped foamed glass product;

FIG. 13A and B illustrate an arcuate foamed glass product;

FIG. 14A-D illustrate a foamed glass product in the form of a curved segment;

- 3 033664 FIG. 15A, B and C illustrate a foamed glass product in the form of a panel;

FIG. 16 is a cross-sectional view of a semicircular casting mold with expanded foam glass;

FIG. 17A is a top view of the upper leaf of the mold and T-flange reinforcements;

in FIG. 17B shows a T-flange reinforcement;

FIG. 18 is a snapshot depicting an outer sealed surface layer on a pre-molded semi-cylindrical foamed glass component based on CO ₂ 4 600 mm;

FIG. 19 is a snapshot depicting an inner sealed surface layer on a pre-molded semi-cylindrical foam glass component based on CO2 of 4,600 mm;

FIG. 20 is a snapshot depicting an internal porous structure on a pre-molded cylindrical foam glass component based on CO2 of 4,600 mm;

FIG. 21 is a snapshot depicting pre-molded foamed glass based on N2 and O ₂ with a porous structure of the outer surface layer from 0 to 2 mm;

FIG. 22 is a snapshot depicting a pre-molded foam glass based on N ₂ with a porous structure of the outer surface layer from 0 to 1 mm;

FIG. 23 is a snapshot depicting a pre-molded foam glass based on CO ₂ with an outer surface layer. Porous structure from 0 to 4 mm;

FIG. 24 is a snapshot depicting a pre-molded foam glass based on N2 200 mm x 98 mm x 20 mm with an outer surface layer. Porous structure from 0 to 2 mm;

FIG. 25 is a snapshot depicting a sintered tablet of a glass mixture at a temperature of from 650 to 750 ° C;

in FIG. 26 shows a sintered glass mixture of a crescent shape at a temperature of from 650 to 750 ° C;

in FIG. 27 shows a sintered glass mixture re-heated to a temperature of 850 ° C;

FIG. 28 is a snapshot depicting pre-molded foam glass with an internal porous structure based on N ₂ from 0 to 2 mm.

DETAILED DESCRIPTION OF THE INVENTION

According to one aspect of the invention, a method for producing foamed glass components with a smooth outer surface layer is provided. This aspect of the invention will be described with reference to a preferred embodiment comprising a die for casting semi-cylindrical insulating sections for pipes and the like, as shown in FIG. 1, 2 and 3. Although a semicircular profile is shown, it should be understood that other forms are also possible within the scope of the invention.

As shown in FIG. 4, 5A and B, the die for casting includes a lower mold leaf 1 having a lower semicircular profile 2, as shown in detail in FIG. 6, elongated in the longitudinal direction by a certain length, as a rule, from 200 to 600 mm; however, if necessary, it may be longer. The lower leaf 1 may have longitudinal recesses 3 to provide better heat distribution and reduce the weight of the mold.

The mold also includes an upper mold flap 4 having a corresponding upper semicircular profile 5 and a lid 6, shown in detail in FIG. 7. When the upper leaf 4 is attached to the lower leaf 1, a cavity 7 is formed, such as that shown in FIG. 4, having the form of a manufactured component. The upper leaf 4 may have longitudinal recesses 8 to provide better heat distribution and reduce the weight of the mold.

The upper and lower leaflets of the mold have T-flange reinforcements 9 and 10, respectively.

The mold is preferably made of titanium; however, it can also be made of another heat-resistant material, such as graphite.

The radius of the semicircular profiles, as well as the distance between the semicircular surfaces 2 and 5, is determined depending on the diameter of the insulated pipe and the thickness of the required insulation; as a rule, it is from 20 to 50 mm.

As shown in FIG. 8, a weighed mixture of ground glass and a blowing agent is added to the lower leaf 1 of the mold and uniformly distributed along its length, as shown in FIG. 9. The upper leaf 4 of the mold is attached to the lower leaf 1 of the mold and secured in place using the mechanism shown in FIG. 10, 11A, B and C. The locking mechanism includes locking pins 11 that engage the holes 12 with the locking channel 13. The locking channel 13 may be located in the groove 14, as shown in FIG. 17A. The holes 12 in the blocking channel correspond to the holes 15 in the profile 5, as can be seen in FIG. 5A. The locking mechanism is activated by inserting the pins into the holes and sliding the channel in the locking direction 17 or released by sliding in the 18 direction of the hole.

Preferably, a release agent, for example kaolin powder, is applied to the inner surfaces of the cavity of the mold, and more preferably, to all surfaces of the mold

- 4,033,664 water. The purpose of the release agent is to prevent adhesion between the casting component and the mold wall. Kaolin powder is mixed with water to form a suspension, then dried at a temperature of 100-300 ° C for two hours.

The mold, in the case when it is made of titanium, can also be preferably machined over its surfaces using the contact layer 19, as shown in FIG. 4 containing CoNiCrAlY to protect the mold from oxidation at high temperature. The contact layer preferably has the same coefficient of thermal expansion as the mold.

End plates 20 having protrusions 21, as shown in FIG. 9 are attached with slots 22 for engaging with the protrusions shown in FIG. 6, thereby sealing the mold.

The die for casting can be installed on a device that allows the matrix to rotate in the heating zone during the casting phase.

As shown in FIG. 10, channels 23 are located between the lower and upper leaflets of the mold. The channels are designed to relieve excess pressure, allowing you to release excess foamed glass or pressurize during the casting phase by creating pressure throughout the furnace. The channels are shown as a gap between the upper and lower cusps, however, the channels can also be located elsewhere in the mold, provided that the gases can freely stand out and allowing excess foam to leak out during the casting phase.

Although the figures depict a semicircular casting mold for obtaining semicircular pipe insulation, it is possible to mount two dies in one round die casting matrix having two cavities. This may be necessary if induction heating is selected, since it leads to more efficient heat transfer.

In FIG. 12A and B, FIG. 13A and B, FIG. 14 A-D and FIG. 15 A-C show examples of die castings having a T-profile 24, a bend 25, a curve segment 26, and a flat panel 27, respectively. The flat panel can be molded horizontally or vertically.

According to the method, the matrix is filled with a uniformly mixed mixture consisting of finely ground glass containing a fraction, the size of which can vary from 0.005 to 1.6 mm, and up to 15% by weight of a blowing agent including a reaction ingredient and an oxidizing agent. The number of foaming agents and the size of the fractions of ground glass is determined based on the desired density of the foamed glass. The weight filled into the matrix is calculated based on the estimated density of the finished foam glass and the internal volume of the die for casting.

Table 1

Glass Powder / Sheet Glass Reaction ingredient Oxidizing agent Density 88 wt.% SiC 10 wt.% MnO ₂ 2 wt.% 190 kg / m ³ 90 wt.% AIN 10 wt.% MnO ₂ 0 wt.% 225 kg / m ³ 93 wt.% AIN 4 wt.% MnO ₂ 3 wt.% 180 kg / m ³

The casting matrix is sealed and placed in a heating zone, for example, a radiation-heated furnace or an air-circulation furnace, and then heated to a first temperature plateau at least equal to the melting temperature of the glass to form a glass melt. The first temperature plateau is maintained for a sufficient time to allow the reaction ingredient and oxidizing agent to substantially evenly disperse in the molten glass.

Thereafter, the mold is heated to a second temperature plateau in the range of 750 to 1000 ° C., whereby the reaction ingredient and the oxidizing agent react with the formation of gas bubbles inside the molten glass, thereby forming the desired glass foam 28, as shown in FIG. 16. The reaction temperature is maintained while the foamed glass expands and fills the mold cavity. The internal pressure in the mold is from 0 to 3 bar.

Then the mold is gradually cooled to a third temperature plateau from 730 to 650 ° C, allowing the viscosity of the foam to increase and stabilize the shape and size of the component, before a larger drop in temperature inside the gas bubbles leads to a decrease in their volume and deformation of the component. In one aspect, the mold is cooled to a third temperature at a rate of 3 ° C./min or slower.

At this temperature, the foam also forms a strong and durable surface layer 29, 30 and 31 on surfaces in contact with the mold, as can be seen in FIG. 1. This surface layer gives the component high strength and forms a gas- and waterproof membrane, providing additional protection against condensation, water penetration and corrosion under insulation (CUI).

Then the mold is cooled to the fourth temperature plateau in the range from 400 to 250 ° C, relieving internal stresses in the component before being removed from the mold.

After that, the mold is cooled to the fifth temperature plateau, to the temperature of extraction from the mold, at which the foamed glass is sufficiently cured so as not to deform or crack when removed from the mold.

When the mold is sufficiently cooled, the foamed glass component can be extracted from the mold.

table 2

Reaction ingredient 1. Stud Excerpt h: m 2. stage Exposure h: m Lower h: m 3. stage Lower h: m 4. stage Lower h: m 5. stage SiC 800 ° C 1:00 900 ° C 1:00 3 o'clock 720 ° C 12:00 300 ° C 2 a.m. 50 ° C Ain 750 ° C 1:00 870 ° C 0:30 2 a.m. 680 ° C 12:00 300 ° C 2 a.m. 50 ° C

According to another aspect of the invention, the raw material mixture can be sintered to produce preformed pelletized parts during the preliminary firing process at a temperature of from 640 to 750 ° C., as can be seen in FIG. 25 to then either cut them into sickle shaped fragments, as shown in FIG. 26; The crescent shape of the sintered parts of the mixture will accordingly coincide with the curved profile of the mold. This method facilitates the filling of the peripheral parts of the matrix with a more complex geometric shape and provides uniform density and mass distribution.

The heat source may consist of heat from air circulation, as in this case, or heat transmitted by radiation; however, it can also consist of an induction furnace in which a casting die is placed between the induction coils in order to heat it there to the required temperature. If necessary, other suitable sources of indirect heating, for example a gas burner, can also be used.

With increasing temperature of the die for casting, the following occurs: the glass powder melts and decreases in volume, since the structure of particles with gaps between them is compressed. At the same time, the oxidizing agent will decompose with the release of oxygen; when the temperature is high enough, the reaction ingredient will begin to decompose to give off gas, either N2 or CO ₂ , depending on the combination of reaction ingredients selected. Due to the low viscosity of the molten glass, the gas will be evenly distributed in the liquid and form small bubbles. Due to the uniform distribution of the reaction ingredients in the glass powder during heating, and also due to the pressure from the surrounding walls and the pressure exerted by the foamed glass in an attempt to pass through narrow overflow channels, the formation of bubbles will be substantially uniform. The internal gas pressure inside the bubbles will tend to expand the size of the bubbles. The higher the temperature and lower the viscosity of the glass mass, the faster the expansion occurs, and the larger the bubbles become.

In order to avoid fusion of bubbles at an early stage of the process, a seed / nucleation agent may be added to the mixture before homogenization; for example, 0.1-2% finely divided kaolin powder.

According to another aspect of the invention, an insulating product is described. The product is made of foamed glass material having the following physical properties.

The foamed glass material according to the invention is molded in the form of the following types of products.

Prefabricated pipe insulation

A molded pipe insulator including a semicircular profile made of foam glass with a smooth surface layer on the outer and inner surfaces, which is substantially airtight and waterproof, has an internal pore size in the range of 0.2 to 4 mm , outer pore size 14.15.15 from 0 to 1 mm, density below 240 kg / m ³ , compressive strength (ASTM D695) above 2 MPa, tensile strength (ISO 527) above 0.22 MPa, tensile strength by bending (ISO 178) above 0.72 MPa, thermal conductivity at 20 ° C less than 0.060 W / mK and hardening point higher than 850 ° C.

As seen in FIG. 2 and 3, the pipe insulation profiles can be cast with a beveled edge 32 or a groove 33 designed to accommodate a sealing seal.

Prefabricated panels for protection against fire and insulation of walls and pipes

Cast product for fire and insulation protection for drawers, walls and roofs, including a flat profile / panel from 15 to 40 mm thick, made of foamed glass, with a smooth surface layer on all sides 25, 26, which is essentially airtight and waterproof, has an internal pore size in the range of 0.2 mm to 4 mm, an external pore size of 0 to 1 mm, a density below 240 kg / m ³ , compressive strength (ASTM D695) above 2 MPa, tensile strength (ISO 527) above 0.22 MPa, ultimate bending strength ((ISO 178) above 0.72 MPa, thermal conductivity at 20 ° C less than 0 , 060 W / mK and a solidification point above 850 ° C.

- 6,033,664

Description of Embodiments

Table 3

Products Density Pore size Compressive strength Thermal Conductivity W / mK Solidification point Pipe insulation 180 kg / m ³ 0.5 mm - 2 mm 2 MPa 0,038 850 ° C Panels 225 kg / m ³ 0.5 mm - 4 mm 2 MPa 0,040 900 ° C

Table 4

Analysis of thermal conductivity at a temperature of 20 ° C:

Material: 7 wt.% AIN + MnO ₂ and 93 wt.% Sheet glass

No. Repetitions ID sensor Start time Thermal activity W * Vs) (m ² ) K Conductivity (W / mK) t environment ΔΤ (° C) V0 103 1 H191 10:37:50 60 0,040 20.75 2.11 3464.77 104 1 H191 10:39:34 58 0,040 20.52 2.11 3463.09 105 1 H191 10:41:17 58 0,040 20.32 2.11 3461.67 106 1 H191 10:43:00 57 0,040 20.14 2.11 3460.10 107 1 H191 10:45:01 52 0,040 19.98 2.13 3457.78 108 1 H191 10:46:44 57 0,040 19.83 2.11 3457.58 109 1 H191 10:48:27 57 0,040 19.73 2.12 3456.91 110 1 H191 10:50:11 57 0,040 19.64 2.12 3456.03 111 1 H191 10:51:54 58 0,040 19.54 2.12 3455.37 112 1 H191 10:53:37 56 0,040 19.48 2.12 3454.54

CLAIM

Claims (20)

1. A method of manufacturing a foamed glass component by heating a mixture containing crushed or ground glass, a reaction ingredient and an oxidizing agent, characterized in that the method also includes the following steps: a) providing a sealable mold having an internal cavity, the cavity corresponding to the shape of the resulting foamed glass component, filling the mold with the mixture and then sealing the mold, b) placement of the mold inside the heat source, c) heating the mold to a first temperature level at least equal to the melting temperature of the glass, with the formation of a molten glass, d) maintaining the first temperature level for a time sufficient to ensure uniform distribution of the ingredients in the molten glass, e) heating the mold to a second temperature level corresponding to the reaction temperature in the range from 750 to 1000 ° C, in which the reaction ingredient and the oxidizing agent react with the formation of gas bubbles inside the molten glass, as a result of which the molten glass swells to form a glass foam, f) maintaining the mold at least at the reaction temperature until the expanded glass expands and the cavity is filled, g) the gradual cooling of the mold to a third temperature level in the range from 730 to 650 ° C, in which the viscosity of the glass foam inside the mold gradually increases and a sealed surface layer forms on the surface of the foam in contact with the mold, h) the gradual cooling of the mold to the fourth temperature level in the range from 400 to 250 ° C, i) cooling the mold to a fifth temperature level corresponding to removal from the mold at which the foamed glass hardens sufficiently so as not to deform or crack when removed from the mold, and j) removing the foamed glass component from the mold. 2. The method according to claim 1, characterized in that the crushed or ground glass has a fractional size from 0 to 1800 μm, the reaction ingredient is AIN, Si ₃ N ₄ or SiC, and the oxidizing agent is MnO ₂ . 3. The method according to claim 2, characterized in that the foamed glass has an inner pore size in the range from 0.2 to 4 mm, an outer pore size from 0 to 1 mm, a density below 240 kg / m ³ , compression resistance (ASTM D695 ) above 2 MPa, tensile strength (ISO 527) above 0.22 MPa, bending strength (ISO 178) above 0.72 MPa, thermal conductivity at 20 ° C less than 0.060 W / mK and solidification point above 850 ° C . 4. The method according to claim 1, characterized in that the internal pressure in the mold when glass - 7 033664 foam expands, filling the mold, is a positive pressure exceeding atmospheric pressure by a value from 0 to 3 bar. 5. The method according to claim 1, characterized in that the mold is cooled to a third temperature at a rate of 3 ° C / min or slower. 6. The method according to claim 1, characterized in that the mold is made of titanium. 7. The method according to claim 1, characterized in that the inner surface of the cavity of the mold is coated with a release agent. 8. The method according to claim 6, characterized in that the glass mixture further comprises a seed agent. 9. The method according to claim 1, characterized in that the component is a semicircular profile suitable for use as an insulating material for pipes. 10. The method according to claim 1, characterized in that the component is a profile suitable for use as a flame retardant material. 11. The method according to claim 1, characterized in that the component is a flat profile suitable for use as a fireproof panel for roofs and walls in buildings. 12. The method according to claim 1, characterized in that the glass mixture is pre-sintered and formed into prefabricated crescent-shaped parts. 13. The method according to claim 1, characterized in that the mold includes a channel or duct adapted to release excess foamed glass at a given pressure. 14. The method according to claim 1, characterized in that the mold is treated with a contact layer consisting of CoNiCrAlY, as a protection against corrosion. 15. The method according to any one of claims 1 to 14, characterized in that the foamed glass component is an insulation for pipes. 16. The method according to any one of claims 1 to 14, characterized in that the foamed glass component is a building panel. 17. Refractory insulation comprising foamed glass, characterized in that the insulation includes foamed glass obtained by injection molding into a predetermined shape according to the method of claim 1, wherein said foamed glass has a smooth, substantially sealed and waterproof surface layer on its the outer surface, foamed glass of insulation has an internal pore size in the range from 0.2 to 4 mm, an external pore size from 0 to 1 mm, a density below 240 kg / m ³ , compressive strength (ASTM D695) above 2 MPa, tensile strength gap (ISO 527) you above 0.22 MPa, bending strength (ISO 178) is higher than 0.72 MPa, thermal conductivity at 20 ° C is less than 0.060 W / mK and the solidification point is higher than 850 ° C. 18. Insulation according to claim 17, characterized in that the predetermined shape includes an elongated semicircular profile adapted for use as pipe insulation. 19. Insulation according to claim 17, characterized in that the predetermined shape includes a flat panel adapted for use as a building material. 20. The insulation according to claim 17, characterized in that the insulation is substantially transparent for scanning by microwave radiation.