Talking about the construction method of LNG cryogenic storage tank

The cryogenic storage tank is a vertical or horizontal double-layer vacuum insulation storage tank for storing liquid oxygen, nitrogen, argon, carbon dioxide and other media. The operating pressure of the LNG cryogenic storage tank is 15KPa and the operating temperature is -162 ° C. It is a flat-bottomed double-walled cylinder. The tank body is composed of two layers, the inside and the outside, with a heat-insulating structure and a cold-keeping layer. The inner tank is used to store liquefied natural gas, while the outer shell is used to protect and keep cold. In order to reduce the introduction of external heat into the tank, the inner and outer tanks are designed separately and independently.

Today Jianshen pressure vessel will introduce the construction method of LNG storage tank. LNG cryogenic storage tanks can generally be divided into flip-mounted construction and front-mounted construction. Let's look at the advantages and disadvantages between them.

Advantages of flip-chip construction:
1. Both internal and external tanks are constructed by hydraulic jacking. No scaffolding is required. Construction of the internal and external tank walls and tank tops requires cranes (external tank top installation), which greatly reduces the construction cost.
2. Except for tank top installation, all installation and inspection work is performed on the ground, with high work efficiency, which is conducive to quality control and safety management. Disadvantages of flip-chip construction:
1. Unable to carry out parallel operations.
2. During the construction of the tank wall, the tank is already a closed space and the ventilation is not smooth.

Advantages of formal construction:
1. The inner and outer tank walls are alternately constructed, and the working surface is relatively wide. Under the premise that resources can be guaranteed, it is beneficial to shorten the construction period.
2. Since scaffolding is provided inside and outside the tank as well as the interlayer, the repair of the non-destructive testing will not affect the installation of the next wall panel.
3. Tank wall construction is carried out in the open air, and good ventilation is maintained at the construction site.

Disadvantages of construction method:
1. The inside and outside of the tank and the mezzanine must be filled with red scaffolds, and the scaffold has a long service life. During the process of assembling the inner and outer tank roofs and upper parts, large cranes are required for long-term cooperation, and the construction cost is high.
2. There are many high-altitude operations, which reduces work efficiency and brings inconvenience to quality control and safety management.