TECHNOLOGY DEVICES OF HEAT-INSULATING COATINGS 2. Filling thermal insulation

Filling insulation arrange hot and cold surfaces. For filling, fibrous, powdered and granular materials are used - mineral and glass wool, foam plastic, perlite sand, pumice stone, slags, ashes.

Expanded perlite sand is used for insulating backfill at a temperature of insulated surfaces from - 200 to 875 ° C, for thermal insulation of structures of complex shape as backfilling in a specially installed casing. Sand fines are used on hot surfaces, medium and coarse sand is used on surfaces with negative temperatures. To exclude precipitation of material during operation, the structure should not be subjected to vibration.

Expanded vermiculite is a free-flowing, granular material of a flaky structure. This non-combustible material is transported and stored in paper bags in conditions that exclude its moisture, pollution and compaction. It is used as a heat insulating filling at a temperature of insulated surfaces from - 260 to + 1100 ° C and up to +900 ° C when isolating vibrating surfaces.

Means of mechanization feed, lay and level the filling with an even layer of a predetermined thickness with the necessary compaction until reaching the design density on a horizontal surface. The heat insulation must be insulated from external influences of precipitation, blowing, any mechanical damage and deformations. If precipitation is the main external factor, then a roll-up waterproofing carpet is spread over thermal insulation, on top of which a strong cement-sand or asphalt screed is arranged.

If the upper structures are insulated from weathering, then it is enough to perform a protective coating over it - a layer of cement-sand or asphalt screed. Often, especially when building a roofing covering, a protective screed made of the same materials is arranged according to the filled-in thermal insulation, and a multi-layer roll roof is glued on top.

When arranging the backfill waterproofing on vertical surfaces, it is necessary to provide measures that guarantee the rigidity of the heat insulation design solution and fixation of the backfill materials along the entire height of the insulated structure. Metal studs with a diameter of 3 mm and a length corresponding to the thickness of the insulation, with the location of the studs in a checkerboard pattern with a step of up to 350 mm, are fastened in the insulated vertical surface. The studs are tensioned with a metal grid with 15x15 mm cells. Then, in the space between the insulated surface and the grid, the insulator is covered in layers from bottom to top for the entire width of the insulation, each layer is compacted. After the thermal insulation has been performed on a metal grid, a layer of cement-sand plaster 20 mm thick is arranged; upon drying of which, a layer of fabric is pasted on top and painted. Apply a layer of cement-sand plaster, preferably not manually, but by means of gunning, if necessary, arrange a waterproofing layer for thermal insulation.

Filling insulation is distinguished by simplicity of the device, low labor intensity and low cost. The main disadvantages are the low mechanical strength of the insulation, the low resistance of vibration, the settling of the insulation over time and the exposure of the upper layers.