| 摘要 |
<p>PURPOSE:To prevent a plastic insulation from cracks by forming it with layers of foaming plastics and ones with nonfoaming plastics laid one over the other and thereby absorbing the thermal contraction stress generated by temperature difference. CONSTITUTION:A plastic insulation 2 is formed with insulating layers of nonfoaming plastics 7 and ones of foaming plastics 8 laid one over the other. The thermal contraction stress generated by temperature difference between the outside and inside in case this type of insulation is applied to a tank containing such liquid at extra-low temperature as liquefied natural gas and liquid nitrogen, will not cause any longer a thorough crack extending over the full thickness of the plastic insulation, and the tank is thus prevented from deterioration in its insulating performance.</p> |
