HX/XY-RK type breathing manholeDetailed product description：

The main purpose of HX/XY-RK breathing manhole is to develop it based on market demand and advanced technical information at home and abroad. Breathing manhole is a safety emergency ventilation device installed on storage tanks for petroleum, chemical and other materials. Breathing manholes are usually used in conjunction with fire-resistant breathing valves to avoid accidents caused by sudden overpressure or vacuum inside the tank, which can damage the tank; It can also play a role in safety and fire prevention. The breathing manhole is currently the ideal device for protecting tank safety in China, and the product fills the domestic gap.

HX/XY-RK breathing manhole model meaning:


The breathing manhole adopts an all-weather sealing structure, with a counterweight to adjust the opening and closing of the suction valve disc and the relief cover. Stainless steel corrugated tape is used as a flame retardant layer to prevent the passage of flames, and double drawer openings are provided to facilitate the cleaning and replacement of the flame retardant layer, shortening the time. In summary, this breathing manhole has advantages such as constant pressure discharge, constant pressure suction, flexible closure, safe fire resistance, compact structure, good sealing performance, and safety and reliability.

Main technical parameters

1. Operating pressure: positive pressure+1765Pa180mmH20 negative pressure -392Pa-40mmH20.
2. Fire resistance level: BS5501: IIA standardized.
3. Operating temperature:+50-30 ℃.
4. Scope of use: Especially suitable for storing materials in dome shaped atmospheric pressure tanks capped with nitrogen gas.

Working Principle

Under normal operation of the flame retardant breathing valve, the breathing manhole remains sealed and the storage tank is at normal pressure. When the normal operation of the breathing valve cannot meet the sudden overpressure of the storage tank caused by unexpected reasons, the relief cover of the breathing manhole will automatically open for emergency pressure relief to maintain normal pressure inside the tank; When the pressure inside the tank drops sharply or exceeds the vacuum, the suction valve opens to rapidly suck in the atmosphere, maintaining the normal pressure inside the tank; When sparks or flames are inhaled into the atmosphere, the flame barrier acts as a "wall effect" to prevent the flame from passing through and protect the safety of the storage tank.

HX/XY-RK type breathing manhole main material