The HX3/HXF3 breathing valve with suction connection is a bidirectional breathing valve installed on the top of a fixed top storage tank. It is equipped with an independent suction connection (which can be connected to nitrogen or other protective gases) and an exhalation channel, integrating positive pressure exhalation, negative pressure safety air supply, and fire prevention functions. When the pressure inside the tank is higher than the set value, the positive pressure valve disc opens, and volatile gases are discharged into the atmosphere or recovery system through the flame retardant layer; When negative pressure is generated inside the tank, the negative pressure valve disc opens, and protective gas (such as nitrogen) or air is introduced through the suction pipe to quickly replenish the pressure inside the tank. This valve is mainly used for nitrogen sealing protection and safety ventilation system of storage tanks. Its core purpose is to automatically supplement dry inert gas through suction connection when the tank is discharged or the temperature drops sharply, preventing air from entering the tank and forming explosive mixtures. At the same time, it has overpressure relief and flame retardant functions, ensuring the safety of the storage tank and the quality of the medium.

HX3 and HXF3 breathing valves with suction connection product diagram

1. Independent suction pipe design: The dedicated suction pipe can be connected to a nitrogen pipe network or an air filter to achieve controlled air supply and avoid direct suction of external humid air or dust when the tank is under negative pressure.

2. Bi directional breathing function: The positive pressure valve disc and negative pressure valve disc operate independently, allowing for overpressure exhalation and negative pressure inhalation. The pressure setting value can be adjusted as needed.

3. Built in flame retardant layer: using stainless steel corrugated plate flame retardant core, effectively blocking flame propagation, in compliance with the fire prevention regulations for petrochemical storage tanks.

4. Constant pressure opening and closing, reliable sealing: The valve disc and seat adopt flat or conical hard sealing, and the opening pressure and reseating pressure are stable, with zero leakage when closing.

5. All day protective structure: The top is equipped with a rain and dust cover, and the internal drainage design prevents water accumulation, making it suitable for harsh outdoor environments.

6. Corrosion resistant material: The valve body can be made of aluminum alloy, cast steel or stainless steel, and the valve disc and flame retardant core are made of stainless steel, suitable for various corrosive media.

7. High ventilation volume, low pressure drop: optimized flow channel design, low respiratory resistance, meeting the exhaust and replenishment needs of the storage tank during rapid liquid inflow and outflow.

8. Easy maintenance: The flame retardant core can be removed for cleaning, the valve disc component is easy to disassemble, and the suction connection interface is standardized for easy connection.

HX3 type with suction connection breathing valve DN50-250    HXF3 type with suction connection flame retardant breathing valve DN50-250、

Drawing of Parts

Performance Specification Table

Operation Pressure Reference Table

HX3 type with suction connection breathing valve DN50-250    HXF3 type with suction connection flame retardant breathing valve DN50-250

Outline dimension table