LNG elastic felt is mainly used for insulation of liquefied natural gas storage tanks, cryogenic pipelines, and cryogenic equipment. Its construction quality directly affects the system's insulation effect, structural safety, and long-term operational stability. Due to the extremely low application temperature range, the requirements for detail control during construction are significantly higher than for conventional insulation materials.

I. Material and Environmental Inspection Before Construction

Before construction, verify that the specifications, thickness, density, and design conditions of the LNG elastic felt match the design conditions, paying particular attention to its applicable minimum temperature and elastic recovery performance. Materials should be stored in their original packaging, avoiding direct sunlight, rain, or prolonged compression.

The construction environment should be kept dry and clean. The substrate surface must be free of oil, moisture, frost, or sharp protrusions. If the substrate moisture content is too high, it must be dried first; otherwise, interface frost or delamination risks may occur during low-temperature operation.

II. Substrate Treatment and Adhesion Requirements

LNG elastic felt relies on good adhesion to achieve a continuous insulation layer. Before construction, the surface of metal pipelines or equipment should be cleaned and given necessary anti-corrosion treatment. The anti-corrosion layer must be fully cured before insulation construction can begin.

During installation, ensure the elastic felt adheres tightly to the substrate, avoiding any gaps, bulges, or obvious wrinkles. Poor adhesion can create localized cold bridges at low temperatures, increasing cold loss and potentially causing frost formation.

III. Cutting and Wrapping Construction Key Points

Use sharp tools to cut the elastic felt, ensuring accurate dimensions and tight joints. The cut surface should be smooth to avoid tearing the material structure, which would affect its elasticity and low-temperature adaptability.

During wrapping, spread the material evenly along the pipeline or equipment structure, avoiding forced stretching. Excessive stretching can create internal stress during low-temperature contraction, potentially leading to joint cracking or localized detachment.

IV. Overlap and Joint Treatment Requirements

Joints are a critical control point in LNG elastic felt installation. Adjacent materials should be overlapped appropriately, with overlap widths meeting design and process requirements to ensure a continuous insulation layer.

All joints should be tightly sealed with a system-compatible sealant to prevent cold air intrusion and moisture penetration. When constructing multi-layer structures, the joints of each layer should be staggered to avoid forming continuous cold bridges.

V. Precautions for Multi-Layer Structure Construction

In LNG cryogenic systems, elastic felt is typically constructed using a multi-layered stacked structure. During construction, each layer should be laid strictly according to the design sequence. After each layer is completed, its fit, integrity, and sealing should be checked before proceeding to the next layer.

No impurities or air layers should be trapped between layers to prevent localized frost formation or interlayer slippage during low-temperature operation.

VI. Moisture-proofing and External Protective Layer Construction Requirements

While LNG elastic felt itself has a certain resistance to cold shrinkage, the overall moisture-proof performance of the system depends on the external protective structure. During construction, ensure the moisture-proof layer is continuous and undamaged, and pay special attention to sealing the joints.

The external protective layer should possess sufficient mechanical strength to prevent damage from external forces during operation or maintenance, and to prevent structural loosening due to temperature changes.

VII. Fixing Methods and Stress Control

The installation of fasteners should adhere to the principle of "stable without compressing." The spacing between fixing points must meet design requirements to avoid localized stress concentration.

Metal clamps or binding straps should not be used to directly compress the elastic felt. Isolation or cushioning measures should be taken to prevent the material from being compressed and deformed during long-term low-temperature operation.

VIII. Key Inspection Points After Construction

After construction, the following should be checked:

Whether the insulation layer is continuous and intact;

Whether the joints and overlaps are reliably sealed;

Whether the material shows obvious stretching, damage, or compression;

Whether the moisture-proof and external protective structures are airtight.

If necessary, local inspections or cold-state verifications can be conducted before system commissioning to identify potential risks in advance.

Overall, the core of LNG elastic felt construction lies in the control of continuity, fit, and sealing. Only by strictly adhering to process requirements during the construction phase can its elastic adaptability and long-term stable insulation performance in extremely low-temperature environments be fully utilized.