Explain the mechanical properties of insulating materials.

1 Answer

Answer :

i) Mechanical strength: Mechanical strength depends on temperature and humidity. a) Temperature: High temperature badly affects the mechanical strength of insulating material. While selecting material precautions should be taken that it should withstand high temperature. b) Humidity: Non-hygroscopic materials should be selected, humidity badly affects mechanical strength. 

ii) Viscosity: Viscosity is important in liquid dielectrics used in varnishes for impregnation. Low viscosity liquids are more mobile and helpful in transmission of heat by circulation. iii) Porosity: High porosity insulating materials will increase the moisture holding capacity, which is harmful for insulating material, hence porosity is undesired. 

iv) Solubility: In some cases, the insulation can be applied only after dissolving, it in some solvent. 

v) Mouldability: In manufacturing solid insulating material should have property of easy moulding and machined into required shape and size.

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