Product Catalog
Breathing Manhole
Breather Manhole is a large-diameter safety venting device installed on the top of atmospheric and low-pressure storage tanks. It can be used in conjunction with breather valves or independently, providing routine breathing as well as emergency overpressure and vacuum protection. It enables ultra-high-flow pressure relief during fire accidents, integrating flame arrest, sealing and environmental protection functions.
- Parameters
- Drawing
- Application areas
Working Principle
Overpressure Venting: When tank internal pressure exceeds the set value of the breather manhole, the exhaust disc fully opens automatically to release pressure at high flow rate; the disc reseals when pressure drops to approximately 90% of the set point.
Negative Pressure Intake: When tank negative pressure exceeds the set value of the breather manhole, the intake disc fully opens automatically for high-flow pressure compensation; the disc reseals when pressure rises back to around 90% of the set point.
Sealed Standby: Under normal operating pressure, the disc is sealed by its own weight or spring force to isolate ambient air and reduce medium volatilization.
Applicable Standards
HG/T 21515-2014, Atmospheric Manholes
API Standard 2000, Venting of Atmospheric and Low-Pressure Storage Tanks (Standard for High-Flow Venting Equipment)
Product Features
Low opening-closing differential pressure; the lift height reaches at least 1/3 of the nominal diameter of the breather manhole.
Equipped with high-quality springs featuring excellent anti-fatigue performance.
Multiple optional materials are available for valve seat and valve plug fabrication, suitable for various working conditions.
Both valve plug and valve seat assemblies are field-replaceable.
Certified discharge curves applicable to all product sizes.
Flange standards can be customized as per customer requirements (GB, HG, ANSI, DIN, GOST).
Parameter
| Parameter Item | Standard Value | Optional / Remarks |
|---|---|---|
| Nominal Diameter | DN400 ~ DN600 | Common sizes: DN400/500/600 |
| Type | Weight-loaded type, Spring-loaded type | Select according to operating pressure |
| Set Pressure | Exhale: Max. 100 kPa / Inhale: Min. -3 kPa | Conventional values |
| Housing Material | Carbon Steel (Q235, WCB), 304 Stainless Steel, 316L Stainless Steel, Aluminum Alloy, Steel lined with PTFE | 316L is selected for anti-corrosion service |
| Disc Material | Aluminum Alloy, 304 Stainless Steel, 316L Stainless Steel | Light weight, excellent sealing performance |
| Sealing Elements | PTFE, FKM (Fluoroelastomer) | Oil resistance & solvent resistance |
| Flange Standard | Flanges compliant with GB, HG, ANSI, DIN, GOST | Non-standard customization available |
| Optional Accessories | Flame arrestor function, heat tracing function | Select according to medium characteristics |
| All data above are for reference only. Please contact us for detailed parameters. | ||
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