As liquefied natural gas (LNG) continues to increase its share in the energy mix, LNG receiving terminals, storage tanks, and cryogenic transportation systems place higher demands on the performance and stability of insulation materials. LNG operating temperatures typically drop to around -162℃, requiring insulation systems to not only possess excellent thermal insulation capabilities but also maintain structural and performance stability in long-term low-temperature environments. LNG elastic felt, as a crucial material in cryogenic insulation systems, directly impacts system safety and energy efficiency. This article will analyze its material properties, thermal performance, mechanical stability, and environmental adaptability.

I. Material Properties of LNG Elastic Felt

LNG elastic felt is typically made from flexible fiber materials or modified elastomer composite structures, exhibiting excellent low-temperature flexibility and shrinkage resistance. Compared to traditional rigid insulation materials, elastic felt is less prone to brittleness in extremely low-temperature environments and can adapt to low-temperature shrinkage deformation.

Its main characteristics include:

1. Low thermal conductivity, reducing cold loss.

2. Good flexibility, adapting to tank and pipeline deformation.

3. Strong resistance to low-temperature embrittlement.

4. Possesses certain earthquake resistance and buffering capabilities.

These fundamental properties provide the conditions for its long-term stable operation in LNG insulation systems.

II. Thermal Performance Stability Analysis

In LNG systems, the temperature difference is enormous, exceeding 150℃. If the insulation material's performance is unstable, it will lead to increased cold loss and even frost formation.

LNG elastic felt exhibits minimal change in thermal conductivity at low temperatures. After low-temperature cycling tests, the material structure remains stable and does not develop significant cracks due to repeated cooling and contraction. With a reasonable thickness design, it can effectively control cold loss and maintain system thermal balance.

Furthermore, the elastic structure can absorb a certain amount of thermal stress, reducing internal stress concentration caused by temperature gradients, thereby improving overall stability.

III. Low-Temperature Shrinkage and Structural Adaptability

LNG systems experience significant shrinkage during cooling. If the insulation material cannot adapt to the deformation synchronously, cracking or delamination is likely to occur. The advantage of elastic felt lies in its flexible structure, which can adjust its shape according to equipment shrinkage, reducing interfacial stress.

In large storage tanks and complex pipeline joints, elastic felt is easier to continuously cover, reducing the number of seams and thus lowering the risk of cold bridging. This structural adaptability is one of the key indicators for assessing system stability.

IV. Moisture and Vapor Control Capabilities

Cryogenic systems have extremely high requirements for moisture control. Once moisture enters the insulation layer and freezes, it can lead to structural damage. LNG elastic felt is typically used in conjunction with a moisture barrier and sealing system to form a complete moisture barrier system.

If the material itself has hydrophobic properties, the risk of water absorption can be further reduced. With proper design and construction specifications, the impact of moisture penetration on system stability can be effectively controlled.

V. Mechanical Stability and Vibration Resistance

LNG transportation systems may experience operational vibrations and external loads. Elastic felt has a certain buffering capacity, which can reduce the impact of vibrations on the insulation layer and reduce the risk of material pulverization or breakage.

In practical engineering, the overall mechanical stability of the system can be further enhanced through reasonable fixing methods and external protective structure design.

VI. Key Factors Affecting Long-Term Stability

1. Material Quality and Manufacturing Process Level

2. Is the overall structural design of the insulation system scientific?

3. Construction quality of the moisture-proof layer and sealing layer.

4. Is external mechanical protection adequate?

5. Regular inspection and maintenance management.

If the above aspects are properly controlled, the LNG elastic felt insulation system can typically achieve a stable operating cycle of over 20 years.

VII. Overall Conclusion

LNG elastic felt exhibits excellent thermal stability and structural adaptability in ultra-low temperature environments. Its flexibility effectively alleviates low-temperature shrinkage stress and reduces the risk of material cracking. Under reasonable design and standardized construction conditions, the system can maintain a stable cold insulation effect for a long period.

For LNG storage and transportation projects, selecting stable elastic felt materials and constructing a complete moisture-proof and protective system are crucial guarantees for ensuring safe system operation and energy efficiency. With the continuous improvement of cryogenic engineering technology, LNG elastic felt will play an even more critical role in high-standard cold insulation systems.