Respiratory valve is a safe and energy-saving product to maintain the pressure balance of storage tank and reduce the volatility of medium. Respiratory valve makes full use of the pressure-bearing capacity of storage tank to reduce medium discharge. Its principle is to control the positive exhaust pressure and negative suction pressure of storage tank by using the weight of positive and negative pressure valve discs.When the medium is pumped out of the tank, so that the pressure of the upper gas space inside the tank decreases, reaching the negative operating pressure of the breathing valve, the atmosphere outside the tank will open the negative pressure valve disc of the breathing valve, so that the outside gas enters the tank, so that the pressure in the tank will not continue to drop, so as to balance the pressure inside and outside the tank, so as to protect the safety device of the tank.
