Breathing valve is a kind of air breather which install on the petrochemical fixed storage tank, in order to avoid tank over the pressure or over vacuum making the storage tank destruct, prevent the outside flame enter ,reduce the tank fluid volatile.
Model QHXF-2000 is designed to vent to atmosphere to protect your tank from damage created by over-pressure or excessive vacuum.Costly product evaporation losses due to normal tank "breathing" are greatly reduced.Because it retains toxic vapous,atmospheric contamination is minimized.This helps to provide increased fire protection and safety.
Most atmospheric tanks require a venting device that will allow large volumes of vapor to escape under relatively low pressures. Usually the allowable set pressure is in inches of water column pressure, both for positive and vacuum conditions. This is because most large storage tanks have a relatively low maximum allowable working pressure.
Operating pressure: Type A: +355pa(+36mmH2O) -295pa(-30mmH2O) Type B: +980pa(+100mmH2O) -295pa(-30mmH2O) Type C: +1970pa(+200mmH2O) -295pa(-30mmH2O) Type D: according to user requirement (special pressure rating)
Note: under normal circumstances, (fire) breathing valve operating pressure to B shall prevail;
Applicable materials: gasoline, kerosene, diesel, aromatics, sulfur, air and other petrochemical materials;