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Why tank insulation is provided on refrigerated cargo tanks?

Thermal insulation must be fitted to refrigerated cargo tanks for the following reasons:
• To minimise heat flow into cargo tanks, thus reducing boil-off.
• To protect the tanker structure around the cargo tanks from the effects of low temperature.
 

Insulation materials for use on gas carriers should possess the following main characteristics:
• Low thermal conductivity.
• Ability to bear loads.
• Ability to withstand mechanical damage.
• Light weight.
• Unaffected by cargo liquid or vapour.

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