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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