In the field of cryogenic insulation, the choice of materials directly affects the thermal efficiency and safety of the system. LNG elastic felt and rubber-plastic materials are currently two major insulation materials widely used in cryogenic engineering. Especially in cryogenic systems such as liquefied natural gas (LNG), liquefied petroleum gas (LPG), and chilled water pipelines, the quality of insulation is crucial. This article will compare and analyze the cryogenic performance of LNG elastic felt and rubber-plastic materials from multiple perspectives, including material structure, insulation performance, anti-condensation capability, and application scenarios, to help engineers select the most suitable cryogenic insulation material based on actual needs.

I. Differences in Material Structure and Basic Properties

1. Material Structure of LNG Elastic Felt

LNG elastic felt is a flexible composite insulation material specifically designed for cryogenic environments, typically made of composite materials such as polyurethane, rubber, and glass fiber. Its internal microporous structure effectively reduces heat transfer and possesses an extremely low thermal conductivity. LNG elastic felt has high resistance to cold shrinkage and can maintain stable insulation performance in cryogenic environments.

2. Structural Characteristics of Rubber and Plastic Materials

Rubber and plastic materials (such as closed-cell rubber and plastic insulation materials) are mainly made of synthetic rubber, forming a closed-cell structure through a foaming process. The closed-cell structure of rubber and plastic materials effectively prevents water vapor penetration and condensation, and possesses a certain degree of flexibility, making them suitable for complex pipe and equipment surfaces.

II. Comparison of Low-Temperature Insulation Performance

1. Insulation Effect of LNG Elastic Felt

LNG elastic felt typically has a thermal conductivity between 0.018 and 0.023 W/(m·K), exhibiting excellent insulation performance, especially suitable for low-temperature systems such as cryogenic storage tanks, pipelines, and heat exchange equipment. Due to its ultra-thin and highly efficient insulation characteristics, it can provide excellent thermal insulation even with a thin layer thickness.

2. Insulation Effect of Rubber and Plastic Materials

The thermal conductivity of rubber and plastic materials is typically between 0.032 and 0.038 W/(m·K), which is relatively high. Especially in low-temperature environments, its insulation performance is not as good as that of LNG elastic felt. While rubber and plastic materials are widely used in conventional cryogenic pipeline insulation, achieving the same insulation effect as LNG elastic felt typically requires a larger thickness.

III. Comparison of Anti-condensation Performance

1. Anti-condensation Performance of LNG Elastic Felt

LNG elastic felt has an extremely low thermal conductivity and excellent closed-cell structure, effectively isolating the internal system from the effects of external temperature changes and preventing condensation on the pipeline surface. Especially in scenarios with large temperature fluctuations, LNG elastic felt exhibits strong anti-condensation capabilities.

2. Anti-condensation Capacity of Rubber and Plastic Materials

Rubber and plastic materials have a good closed-cell structure, preventing water vapor from entering the insulation layer and reducing the risk of condensation. Their anti-condensation performance is excellent in cryogenic systems, especially suitable for systems such as chilled water pipelines and refrigerant pipelines.

IV. Comparison of Resistance to Cold Shrinkage

1. Resistance to Cold Shrinkage of LNG Elastic Felt

LNG elastic felt has extremely strong resistance to cold shrinkage, able to withstand temperature differences in cryogenic environments, and will not loosen or crack during long-term operation at low temperatures. This allows LNG elastic felt to maintain stable insulation performance even under extreme low temperatures and large temperature variations.

2. Resistance to Cold Shrinkage of Rubber and Plastic Materials

Although rubber and plastic materials have good resistance to cold shrinkage, their stability at extremely low temperatures is relatively poor compared to LNG elastic felt, especially in environments with large temperature differences, where the insulation layer may shrink or crack.

V. Comparison of Applicable Scenarios

| Application Scenarios | LNG Elastic Felt | Rubber and Plastic Materials |

| ------ | ------- | ----- |

| Cryogenic Pipeline Insulation | ✔ Preferred | ✔ Commonly Used |

| LNG Storage Tanks | ✔ Applicable | △ Not Recommended |

| Chilled Water Pipelines | △ General | ✔ Commonly Used |

| Refrigerant Pipelines | △ Not Recommended | ✔ Preferred |

| High Temperature Fluctuation Environment | ✔ Applicable | △ Not Recommended |

From the perspective of applicable scenarios, LNG elastic felt is more suitable for scenarios with extremely high requirements for low temperature insulation, such as cryogenic storage tanks and LNG transportation pipelines, while rubber and plastic materials are more suitable for low temperature environments such as conventional refrigeration pipelines and air conditioning systems.

VI. Economic Efficiency and Long-Term Benefit Analysis

LNG Elastic Felt: Initial investment is higher, but due to its ultra-thin insulation effect, it can bring significant long-term benefits in energy saving and space utilization. Suitable for projects with high requirements for insulation performance, especially under conditions of large temperature fluctuations.

Rubber and plastic materials: Low initial cost, easy construction, suitable for most conventional cryogenic systems, and cost-effective. However, due to the need for greater thickness to achieve the same insulation effect, long-term energy consumption is relatively high.

A comparison of the cryogenic performance of LNG elastic felt and rubber and plastic materials shows that LNG elastic felt has significantly better insulation performance and resistance to cold shrinkage in cryogenic environments than rubber and plastic materials. The ultra-low thermal conductivity of aerogel makes it more advantageous in projects requiring energy conservation and with limited space, while rubber and plastic materials offer better economy and construction flexibility in conventional cryogenic environments.

Therefore, when selecting cryogenic insulation materials, engineers should consider the specific needs of the project, budget, construction conditions, and long-term operational benefits to choose the most suitable material.