Van Ha,
Mover did not disrespect you. I suspect there could be a slight problem with the translation between your two languages but not much.
This part of his answer is exactly correct.
"Anyway, a cold box is a method of insulating (usually) an air separation plant. Rather than insulating each pipe, component, vessel etc., the entire process train and distillation column is contained in a box filled with insulating material. The piping etc. expands and contracts within the grains of insulation material (sometimes called Perlite), hopefully without too much resistance."
If I would gotten to your question before Mover, I would maybe have used slightly different words but I would have said the same thing.
Please give him the benefit of the doubt.
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Jop