As a liquid nitrogen transfer and supply vessel, self-pressurising liquid nitrogen tanks focus on the transfer of liquid nitrogen!
Throughout the supply of liquid nitrogen, the valves of the transfer containers are activated and the pipes are kept open.
With less valves used correctly, pressurisation is difficult to achieve; if the pipes are not open, even if pressurisation is achieved, the liquid nitrogen will not be output!
In practice, liquid nitrogen transfer vessel transfer failures also tend to come from pipes that are frozen, and the reason for this is improper use!
So what should I do if I accidentally encounter frozen pipes?
The freezing of the pipes is still caused by water molecules entering the tank and coming into contact with the low temperature of liquid nitrogen.
To solve this, apart from melting the freeze, you have to avoid the re-entry of moist water molecules in the air!
Firstly, the ice melting operation of the liquid nitrogen transfer vessel.
(a)Do not be tempted to knock on the valve in an attempt to shatter the ice by vibration until the location of the ice jam has been determined internally.
The correct way to handle this is to empty the liner of the liquid nitrogen transfer vessel before proceeding with the ice melt.
1.Emptying the liquid nitrogen container: close the booster valve, open the drain valve and empty the valve, feed the dry gas through the emptying valve, increase the pressure inside the container and empty the residual liquid nitrogen under pressure.
2.Ice melting: Blow out the ice blocked pipe with dry hot nitrogen to blow out the ice and then drain the liquid.
Avoiding the entry of moist water molecules is even easier, just open the drain valve when the liquid nitrogen output is complete!
A lot of ice jams in pipes are caused by not opening the venting valve in time when the liquid nitrogen transfer vessel is at rest!