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Thermal insulation



The pipe carrying the fluids at a high temperature should be properly insulated to avoid heat loss to the surroundings. The insulation material should have low co-efficient of thermal conductivity. It should not damage the pipe material and should be able to resist the temperature to which it is subjected. Generally “Rock wool” is used for thermal insulation inpower plant.

                                                

                                    Figure: Rock wool Lath Lord.

Use of insulation:

Serial No:
                    Name of insulation
                     Use
1
Magnesia: Magnesia contains 85% carbonate of magnesium and 15% of binder
It is used for temperature up to 3250C
2
Asbestos fiber
It is used for temperature up
to 5000C

3
Mineral wool
It is used for temperature up
to 8750C
4
Expanded mica, hair felt and cork
It is used for temperature up
to 1250C

5
Glass wool
It is used for temperature up
to 3500C


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