After the air is compressed by the air compressor, after dust removal, oil removal and drying, it enters the air storage tank, enters the left adsorption tower through the air intake valve and the left suction intake valve. The pressure of the tower rises, the oxygen molecules in the compressed air are adsorbed by carbon molecular sieve, and the unadsorbed nitrogen passes through the adsorption bed and enters the nitrogen storage tank through the left suction valve and the nitrogen gas production valve. This process is called left suction. The duration is tens of seconds.

After the end of the left suction process, the left adsorption tower and the right adsorption tower are connected through the upper and lower pressure balancing valves, so that the pressure of the two towers is balanced, this process is called pressure balancing, and the duration is 2 to 3 seconds. After the end of pressure equalization, the compressed air enters the right adsorption tower through the air intake valve and the right suction intake valve, the oxygen molecules in the compressed air are adsorbed by carbon molecular sieve, and the enriched nitrogen enters the nitrogen storage tank through the right suction gas valve and the nitrogen gas production valve, this process is called right suction, and the duration is tens of seconds.

At the same time, the oxygen adsorbed by the carbon molecular sieve in the left adsorption tower is released back to the atmosphere through the pressure reduction of the left exhaust valve, which is called desorption. On the contrary, when the left column adsorbs, the right column also desorbs.

In order to completely discharge the oxygen released from the pressure reduction in the molecular sieve to the atmosphere, nitrogen is blown through a normally open reverse blow valve to purge the desorption adsorption tower and blow the oxygen in the tower out of the adsorption tower. This process is called blowback, and it goes hand in hand with desorption.

After the end of the right suction, enter the pressure balancing process, and then switch to the left suction process, and continue the cycle. 

The work flow of the nitrogen machine is completed by the programmable controller controlling three two-position five-way pilot solenoid valves, and then the solenoid valves respectively control the opening and closing of eight pneumatic pipeline valves. Three two-position five-way pilot solenoid valves respectively control the state of left suction, pressure balancing and right suction. The time flow of left suction, pressure balancing and right suction has been stored in the programmable controller. In the state of power failure, the pilot gas of three two-position five-way pilot solenoid valves is connected to the closing port of the pneumatic pipeline valve. When the process is in the left suction state, the solenoid valve controlling the left suction is powered on, and the pilot gas is connected to the opening port of the left suction intake valve, the left suction production valve and the right exhaust valve, so that these three valves are opened to complete the left suction process and the right adsorption tower desorption. When the process is in the state of pressure balancing, the solenoid valve that controls pressure balancing is energized, and other valves are closed; The pilot gas is connected to the opening port of the upper pressure balancing valve and the lower pressure balancing valve to open the two valves and complete the pressure balancing process. When the process is in the right suction state, the solenoid valve that controls the right suction is powered on, and the pilot gas is connected to the right suction intake valve, right suction production valve and left exhaust valve opening port, so that these three valves are opened to complete the right suction process and the left adsorption tower desorption. In each process, all valves except those that should be opened should be closed.