NORHOF N2 Cold Gas Supply System #855 Series
Norhof manufactures N2 cold gas supply systems. Nitrogen (LN2) is used as the cooling medium and is taken from a storage vessel (Dewar) with low pressure (max. 300 mBar) and delivered (pumped) through a line to the application in a gaseous cold flow
Working principle
The pressure above the liquid level inside the Dewar is built by heating a small amount of liquid in the bottom of the Dewar. With only up to 300 mBar of overpressure, the cold gas will gentle flow out of the outlet pipe. In these systems a pressure less storage Dewar is used as a reservoir for LN2. On the Dewar our unique cold gas pump is mounted. Inside the housing of the pump a microprocessor is used to control the various actions, depending upon the mode selected. The selection of a particular mode is made by a 16-position switch, also located inside the pump housing. By controlling the pressure at time of cold gas transport, the flow is controlled and thus any temperature between ambient and -160°C can be realized.
Important:
cold N2 gas supply may have its application advantages, however, important to know it has much lower heat removal capacity compared with liquid Nitrogen
Any #855 series model will work without modifications as:
– autonomous stand-alone unit;
– direct remote controlled unit;
(controlled by your existing PID controller, PLC, computer with A/D conversion card, etc.);
– will operate on 24 V, DC or with our power supply (115V or 230 V);
– a system with almost no installation time required.
– no need for a pressurized supply of LN2;
– no need for a cryogenic solenoid valve ;
– no need for additional control instruments.
When LN2 is required, a small overpressure is generated by a small heater element in the LN2, and liquid flows out of the system like water from a tap, without spilling, noise, vibrations etc.
Software
To display sensor temperature, vessel pressure, status of LED’s on the pump etc. our Norhof Monitoring software is included with #855 series pump. This software works under Windows ’98 – 2000 – ME – NT – Vista – W7 – Windows 10 – Windows 11
