Thermo-insulation

Exfoliated vermiculite and materials based on it are very effective for heat and fire insulation of industrial equipment. This area of application is determined by high porosity, large reflectivity, low thermal conductivity and high thermal vermiculite.

 

The leading specialists of the company "Ukrainian Vermiculite Group developed an effective insulation board materials ПВТ TU U26.8-33909284-002: 2006, combining high thermal insulation properties with a sufficiently high temperature resistance up to 1200 ºC, durability, and low density.

 

Heat insulating vermiculite products can be used for isolation units with a working temperature of 900-1200 ºC. They have less shrinkage during operation than ultra lightweight, and high elasticity of the particles of vermiculite provides the possibility of large-scale products.



Technical indicators ПВТ products :


п/п
Options Units Description
1 Length (max) mm 2340
2 Width (max) mm 1200
3 Thickness mm 20 – 65
4 Density kg/m3 350 – 600
5 Tensile strength:
- Bending
kg/sm2 5 – 15
6 - Compression kg/sm2 6 – 20
7 Thermal conductivity at 25 oС Wt/m•K 0,09 – 0,18
8 Thermal conductivity at 600 oС Wt/m•K 0,19
9 Thermal conductivity at 900 oС Wt/m•K 0,24
10 Absorption (24 hours) % 0 – 80
11 Residual moisture % max 5
12 Application temperature oС от -50 до +1100
13 Linear shrinkage temperature % max 2
14 Sound absorption at a frequency of 500 Hz   0,4 – 0,6
15 Toxicity effects of temperature   not
16 Flammability   not



Heat insulating vermiculite plates have found widespread use in the isolation of heating units:


Плиты

• Removable panels cover the annular furnace;


• External insulation of glass furnaces;


• Lining of roller kiln;


• Insulation of electrolyzers.




Example of vermiculite board in the vaults of electrolysis instead of fireclay bricks at equal other indicators:

Options Fireclay brick Vermiculite board
Coefficient of thermal conductivity at 500 ºC W / mK 1,13 0,16
Application temperature ºC 1600 1200
The thickness of the body (cm) 55 12
Body weight (kg) 2500 400
The surface temperature of ºC 106 81



Practice operation codes electrolyzers showed that the use of vermiculite plates in the vaults can:


• reduce body weight by low-density plates;


• reduce the temperature of the external surface of the body due to low thermal conductivity material;


• reduce the voltage on the heating bath at 0,1 - 0,3 V;


• save 1,5-2% of electricity.



If you use an ПВТ board, as the insulation increases energy savings and lifetime of the aggregates. Moreover, high temperature applications and low density makes it possible to use an OEM board for thermal insulation of any power equipment.

 

Thus, operation in isolation glass furnaces showed that the product must have a temperature of not less than 1000 oС, sizes of products are: the length of 300-500 mm, width 230-500 mm bacor, 370 mm or more in the hanging walls, the thickness of 50-150 mm (insulation thickness).

 

Maximum deviations from the nominal size should be more stringent in the case of execution discrete isolation bacor and less rigid in the solid insulation hanging from the walls of silica brick.

 

Average density of insulation products depending on operating conditions varies within 400-600 kg/m3.

 

Vermiculite boards successfully passed the test and during operation have not changed their technology, thermal and shrinkage indices.

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