Liaoyang Jinding Cryogenic Equipment Co., Ltd. specializes in the R&D and manufacturing of cryogenic liquid storage and transportation equipment. Main products include cryogenic storage tanks, vaporizers and pressure regulating devices, widely used in metallurgy, chemical, medical, food and other industries.

1. Vacuum Insulation Technology Principle

Liquid nitrogen storage tanks adopt double-wall vacuum powder insulation structure. The inner shell is welded from 16MnDR stainless steel plates with a design temperature of -196°C; the outer shell is made of Q345R pressure vessel steel plates. The interlayer between the inner and outer shells is evacuated to high vacuum (≤5Pa) and filled with perlite (expanded perlite), minimizing heat transferred through conduction, convection and radiation.

2. Interlayer Structure Composition

• Inner shell: 16MnDR stainless steel, corrosion-resistant and low-temperature brittle fracture resistant
• Outer shell: Q345R carbon steel, bearing atmospheric pressure and vacuum negative pressure
• Insulation layer: perlite + high vacuum, maintaining vacuum for long term
• Support structure: bottom base + upper tension belt, reducing cold bridges
• Safety accessories: rupture disc, safety valve, liquid level gauge, pressure gauge

3. Operation and Maintenance Points

1. Regularly check the vacuum level (vacuum transmitter reading should be ≤10Pa);
2. Frost or sweating on the outer shell indicates vacuum failure, and vacuum should be re-evacuated promptly;
3. Calibrate the safety valve once a year and replace the rupture disc every 3-5 years;
4. Avoid overfilling, leaving 10% vapor space.

4. Standards

GB/T 18442 "Fixed Vacuum-Insulated Cryogenic Pressure Vessels", TSG 21 "Safety and Technical Supervision Regulations for Fixed Pressure Vessels".