Cryogenic Liquid Container
Cryogenic liquid containers (commonly referred to as liquid cylinders) are double-walled vacuum vessels designed for reliable and economical transportation and storage of cryogenic gases at temperatures that typically drop below -130degF (9oC). A liquid container offers two main advantages over compressed gas cylinders: 1) it stores large volumes at relatively lower pressure, and 2) providing access to cryogenic liquids that are easily manageable compared to compressed cylinders. Cryogenic liquid containers may sometimes be incorrectly called “dewars”, although dewars are open nonpressurized vessels meant solely for holding cryogenic liquids.
Specification of Cryogenic Liquid Container
| Model | DSW450-175-1.37 | DSW450-175-2.3 | DSW450-195-1.37 | DSW450-195-2.3 | DSW450-210-1.37 | DSW450-210-2.3 | DSW450-210-3.0 | |
| Nominal volume(L) | 175 | 175 | 195 | 195 | 210 | 210 | 210 | |
| Effective capacity(L) | 160 | 160 | 177 | 177 | 191 | 191 | 191 | |
| Dimension(diameter*height) | Φ510*1557 | Φ510*1557 | Φ510*1673 | Φ510*1673 | Φ510*1767 | Φ510*1673 | Φ510*1673 | |
| Working pressure (Mpa) | 1.37 | 2.3 | 1.37 | 2.3 | 1.37 | 2.3 | 3.0 | |
| Safety valve open pressure(Mpa) | 1.59 | 2.41 | 1.59 | 2.41 | 1.59 | 2.41 | 3.45 | |
| Bursting disk open pressure(Mpa) | 2.41 | 3.6 | 2.41 | 3.6 | 2.41 | 3.6 | 5.17 | |
| Evaporation rate(Lin)(%/d) | <2.1 | <2.1 | <2.0 | <2.0 | <2.0 | <2.0 | <2.0 | |
| Empty weight(kg) | ≈130 | ≈142 | ≈133 | ≈152 | ≈131 | ≈165 | ≈165 | |
| Max filling weight (kg) | LO2 | ≈182 | ≈182 | ≈202 | ≈202 | ≈218 | ≈218 | ≈218 |
| LN2 | ≈129 | ≈129 | ≈142 | ≈142 | ≈154 | ≈154 | ≈154 | |
| LAr | ≈224 | ≈224 | ≈248 | ≈248 | ≈268 | ≈268 | ≈268 | |
| LNG | ≈68 | ≈68 | ≈75 | ≈75 | ≈75 | ≈75 | ≈75 | |
| LCO2 | — | ≈188 | — | ≈209 | — | ≈225 | ≈225 | |
| Level gauge | Floating level | Floating level | Floating level | Floating level | Floating level | Floating level | Floating level | |
| Surface treatment | Polish | Polish | Polish | Polish | Polish | Polish | Polish | |
| Base type | Rubber base | Rubber base | Rubber base | Rubber base | Rubber base | Rubber base | Rubber base | |
APPLICATION OF Cryogenic Liquid Container
Cryogenic products commonly available as liquid containers include liquid nitrogen (LIN), liquid argon (LAR), liquid oxygen (LOX), and liquid helium (LHE). Carbon dioxide and nitrous oxide can also be found as refrigerated liquids in similar containers.
While these containers may appear to be well insulated, heat can still infiltrate their products due to an enormous temperature gap between cryogenic liquid and ambient conditions. This heat leak causes some vaporization which if left unused will collect in a space above the liquid and create a pressure build-up.
Head pressure refers to the buildup of air in a container that builds gradually over time and vents periodically through its pressure relief valve, usually venting out via vaporization rates between 0.4% and 3% of its volume per day vaporized through vaporization rates that vary widely within any given day. It’s normal and safe, making up part of its function.
Inspection of cryogenic liquid container:
The relevant welding seams will be subject to 100% RT non-destructive testing and penetrant testing (PT) according to the technological requirements of storage tank production(cryogenic liquid container).
High-purity nitrogen (up to 99.999%) will be used to conduct the strength testing.
Finally, advanced helium mass spectrometer leak detectors (with precision up to 2×10-9Pa.L/s) will be used to conduct Helium mass spectrometer leak detection.
The inner containers of the storage tanks will be passivated by overall pickling to meet the cleanliness requirements for dangerous goods.
Imported ultraviolet black light lamps will be used to make sure that there is no oil stain and other organic impurities in the inner containers.
The inner and outer containers, after cleaning, will be assembled at a time interval of less than 2.5 hours.
After assembling, the inner containers and interlayers will be filled with nitrogen to protect them from dust and organic impurities, to ensure cleanliness.
The inner and outer surfaces of the outer containers will be subject to overall sandblasting treatment to meet the requirements of the Sa-2.5 standard.
When the surfaces of steel plates show a metallic color, a vacuum cleaner will be used to suck off the dust adhered to the surface to further ensure the vacuum degree in the interlayer.
Special high-quality perlite is used as the insulation material in the interlayer.
The perlite will be treated by using our company’s special process before being in the interlayer.
All the internal cylinders, after being manufactured, will be subject to gas-tight and pressure performance tests.
Both the internal and outer cylinders will be subject to rigorous Helium mass spectrum leak detection.
After the production is completed, all the pipe openings will be opened to carry out nitrogen purging and replacement, to meet the oxygen usage standard.
After this, all the pipelines and valves will be sealed and the tanks will be filled with 0.2MPa high-purity nitrogen for protecting the tanks.
