Outlet function module:
When the oil outlet pump runs, the oil inlet pump stops, the oil outlet shut-off valve opens and the oil inlet shut-off valve closes.
The green oil is output outward through the oil outlet pump, and the liquid level of the oil tank decreases slowly. Due to the decrease of the liquid level, the pressure in the oil tank is low. At this time, nitrogen automatically enters the oil tank through the nitrogen sealing valve, so as to maintain the set positive pressure on the tank top At this time, the single call valve and safety relief valve on the tank top are closed.
The pressure transmitter on the top of the oil tank is working and outputs the pressure signal. If the tank top pressure is lower than the lower limit, the computer will give an alarm. If it is lower than the safety interlock value, it will immediately enter the safety interlock state and open the tank top safety relief valve. The oil and gas connected with the tank top pipeline enters the tank to maintain the set positive pressure in the tank. At this time, if the tank top pressure still drops and reaches the set lower and lower limits, the air outside the tank enters the tank through the negative pressure breathing valve to make the pressure in the tank reach the set safety value and achieve the purpose of protecting the tank.