The HX2 / HXF2 flame arrestor breather valve with dual nozzles is a two‑way breather valve installed on the roof of fixed roof storage tanks. It is equipped with two independent piping connections – one for directing excess gas to a recovery system during overpressure, and the other for admitting nitrogen or purified air during vacuum. The valve integrates a pressure disc and a vacuum disc that open automatically at set points, along with a built‑in stainless steel corrugated flame arrestor element to prevent external flame propagation into the tank. Its core purpose is to safely balance tank pressure during filling, emptying, or temperature changes while achieving centralized vent gas recovery and controlled intake gas supply, meeting the combined requirements of vapor recovery, nitrogen blanketing, and explosion‑proof fire protection.

HX2 and HXF2 with dual-connection flame arrester breather valves product diagram

1. Two independent channels – The vent nozzle and intake nozzle are completely separate, avoiding crossflow interference and facilitating connection to recovery networks and gas supply lines respectively.

2. Precise setpressure control – The pressure disc and vacuum disc operate independently at their respective set values, with a tapered metaltometal hard seal ensuring zero leakage after closure.

3. Flame arrestor safety element – Multilayer stainless steel corrugated plate element effectively quenches flames from either direction, meeting petrochemical tank fire safety codes.

4. High capacity, low resistance – Flow path is hydraulically optimized to minimize breathing resistance, accommodating high flow rates during rapid loading/unloading.

5. Corrosionresistant material selection – Housing available in aluminum alloy, carbon steel, or stainless steel; all moving internals are stainless steel, suitable for oil, solvents, and various chemical media.

6. Allweather outdoor design – Top rain and dust cover with internal drainage structure prevents accumulation of water and debris.

7. Easy maintenance – The disc assembly can be extracted as a whole, and the flame arrestor element can be removed for cleaning without pipeline cutting or hot work.