Silicone heat-resistant: varieties and their features

In construction, it is often necessary to seal cracks and joints exposed to high temperature effects. Means for solving such problems must simultaneously withstand temperature fluctuations and maintain plasticity. A real breakthrough in this field was the invention of a special formulation, which is performed on the basis of silicone rubber.

Features of application

Before applying silicate pastes, the surface must be moistened. Silicone heat-resistant should be used at a temperature ranging from +5 to + 40 °. If the temperature of the external environment drops below zero, the composition will not simply freeze. The optimum temperature for use is + 20 °. The master should always use personal protective equipment in the form of gloves, as the sealing silicone mixtures can contain substances that can cause chemical burns on the skin.

In order to avoid contamination of surfaces that should not be exposed to sealant, paint canvas must be used on their bases , which is glued on both sides of the seam. Experts advise to strictly adhere to the instruction, which provides for compliance with the thickness of the seam, it should not be more than recommended. This is due to the fact that there is a risk of cracks in the operation of the material, which may never harden.

Varieties of sealants

Silicone heat-resistant is based on polymers, which can be completely different, which gives the composition certain characteristics. Such mixtures are realized in tubes that can have different volume and configuration. On sale it is possible to meet two-component compositions which before the beginning of works provide for necessity of mixing. Quite often they are used by professionals for the reason that strict requirements are imposed on the staff. When mixing, it is necessary to measure the parts, strictly following the instructions. However, the error is still permissible, but it is only 1 g. If the ingredients are mixed incorrectly, a reaction will occur, and the availability of silicone is only a few hours.

To solve domestic problems, it is best to use one of the types of silicone sealants, which is presented in pasty form, since they are easier to apply. For furnaces and chimneys it is recommended to purchase high-temperature compositions, they are presented for sale in the form of heat-resistant, heat-resistant and heat-resistant materials.

Features of heat-resistant sealants

Silicone heat-resistant is one of the types of described compositions and is used for places that will be heated up to 350 ° during operation. The area of their application is the external surfaces of fireplaces and cracks. With the help of heat-resistant sealant, it is possible to fill the gap between the bricks in the masonry. However, there is no need to use a heat-resistant sealant between stove casting. It can be used to seal sandwich panels and roofing, as well as joints of brick chimneys.

But in this there are exceptions, which are expressed in metal chimneys. But to seal the cracks in the hot water supply system with the help of heat-resistant sealant it is possible.

Description of heat-resistant or heat-resistant sealants

Silicone heat-resistant can be presented in a heat-resistant or heat-resistant form. These compositions can withstand a temperature of 2500 °. In the case of a fireplace or stove, the scope of application is limited to masonry and casting, as well as combustion chambers and combustion chambers in boilers. With regard to chimneys, the heat-resistant sealant can be used in areas of articulation and seams. This should include the place near the outlet pipe of the chimney. These mixtures can be used in areas that are in direct contact with the flame. However, before you buy such a heat-resistant silicone, you should ask whether there are among its characteristics of fire resistance and fire resistance.

Technical characteristics of heat-resistant sealant

Heat resistant sealant is made on the basis of silicone. The temperature regime can vary depending on the composition. Thus, to increase the heat resistance to the ingredients , iron oxide is added . Such sealants cope with the effect of temperature up to 250 °. For a short time, the temperature may rise to 315 °. If iron oxide is present among the ingredients, the paste will have a reddish-brown tinge. Such mixtures are used for fireplaces or stoves made of bricks.

The appearance of the surface when sealing the slots will not be spoiled, since the sealant is almost invisible. It is important to pay attention to the composition of the silicone sealant, since it can be neutral or acidic. In the latter case, acetic acid will be released upon solidification. Such mixtures can not be used with metals that are unstable to corrosion.

Additional features of heat-resistant sealants

The mixtures described above are UV-resistant, so they can be used for external work, as well as for sealing the roofing passage. They are characterized by water resistance and high adhesion. The composition retains plasticity, it does not crack under vibration and deformation. The curing speed can be from several hours to several days, this characteristic will depend on the composition of the mixture.

Technical characteristics of heat-resistant sealants

Sealing silicone heat resistant pastes are intended for filling slots on surfaces operated at a temperature of 1200 to 1300 °. A short-term increase is possible up to 1600 °. Therefore, these sealants are often used in places where direct contact with open fire is possible. If you plan to assemble a chimney or any other structure that will be collapsible, then you need to work joints. When loosening the two links it will be possible to crush the sealant and disconnect the parts. If you glue the surfaces to be glued, the design will be almost monolithic, and it will not be possible to disassemble it without damaging it.

Heat-resistant silicone sealants have poor adhesion to smooth materials, so before applying, the surface must be treated with an abrasive, and then rinsed and degreased again. Before sealing the surface, it is not necessary to wet it, and the dried compound can be removed with a damp rag. Some formulations require the creation of special conditions. Thus, furnace sealants should be dried for several hours at different burning rates. If you follow the instructions exactly, you will be able to get a sealed connection or joint.

Description of the silicone sealant KLSE for creating forms

On sale it is possible to meet one more kind of hermetic - heat-resistant silicone for forms. The obtained products can be operated at a temperature that does not exceed 400 °. If this threshold is higher, then after a while the shape will lose its elasticity. The sealant described is a flowable composition that has a brick color. It is realized as a base and contains a catalyst. Curing takes place for 24 hours at room temperature, as a result, it is possible to get rubber-like products.

The surface of the original, from which it is supposed to take off the form, must be degreased, cleaned of rust and dirt, if the surface is porous, then it is best to use a separating composition. The mixture should process the original product and leave it in that condition for a day or less. If the ambient temperature is below the recommended temperature, the curing time may increase. It will be necessary to work out the compound in half an hour.

Alternative variants of silicone heat-resistant sealants

If you are looking for a heat-resistant cushion, you can choose "Pentelast-1110", which is used as a liquid gasket in joints and for sealing threaded pipelines. It is able to maintain performance at temperatures from -50 to + 250 °. Short-term exposure to high temperatures is also possible, but not more than 10 hours. In this case, the thermometer can rise to 300 °.

With vulcanization, there are no toxic and acidic emissions. If necessary, you can use also food - grade silicone RTV 118 Q, which is colorless and is a one-component glue-sealant. It is applied at room temperature, and in the initial state it is a paste. The application can be carried out on horizontal and vertical surfaces. The operating temperature range varies from -60 to + 260 °.

Other offers

Silicone sheet heat resistant is also popular in carrying out certain types of work. The dimensions of the plate can vary from 300x300 to 500x500 mm. Its thickness varies from 1 to 12 mm. This material is made of silicone and can be used in food equipment at temperatures from -50 to +250 °. The products are safe, chemically resistant, non-toxic and environmentally friendly. Silicone molding is heat-resistant used for the manufacture of gaskets. The latter can be used to seal fixed connections.

But heat-resistant silicone spray is a universal lubricant, which protects and protects metals, rubber or plastic, as well as wood. With its help you can get rid of unpleasant sounds. The material creates a waterproof protective film that does not leave greasy stains.