Let’s discuss what the temperature is inside everyone’s chillers (with pearlescent sand filled in), and what the temperature on the surface of the chillers is

The temperature inside the cold box has not been measured, while the temperature outside the cold box is essentially the ambient temperature. If issues such as \"sweating\" or \"frosting\" occur in certain areas, it may be due to uneven filling of the perlite.

The temperature within the cold box is uneven, with the lowest value being over 80 K

The exact internal temperature is unknown, but the surface temperature is roughly the same as the outside temperature; it changes depending on the environment! If there are liquid droplets or frost on the outer surface above the breather valve or purge valve, it may indicate an internal leak; in such cases, the pearlescent sand needs to be replenished, and if it is not properly placed, similar conditions will appear on the outer surface　

It depends on the specific circumstances. For example, in a cryogenic tank there are low-temperature towers and pipes, and the temperature of the low-temperature liquid can reach well below minus 200 degrees. As a result, the temperature of the steel structure in direct contact with this liquid can be very low. Of course, in most cases, insulating materials such as slag wool are used between the cryogenic container and the steel structure to prevent the steel structure from becoming too cold and becoming brittle. Even so, the steel structure still can reach temperatures in the low teens degrees below zero, because heat can also be transferred through radiation. For the cold box walls, thanks to the insulating effect of the perlite sand, most of the heat loss through radiation and convection can be prevented, allowing the temperature to remain close to normal levels. Of course, except for the leakage of low-temperature liquids inside the cold box. This post was last edited by zjywwjg on 2009-3-6 08:48]

If the pearlescent sand gets wet, the temperature on its surface will be much lower than the ambient temperature, resulting in a loss of insulation effects and serious problems.

The temperature inside the cold box essentially represents the base temperature; there are two temperature measurement points used to monitor the insulation performance – one located near the distillation tower at -4 degrees Celsius, and the other further away at around room temperature. Monitoring is basically not carried out outside the cold box, unless frost forms and sweating occurs on the walls of the cold box.