The composite high-speed exhaust valve is a key piece of equipment in pipeline engineering to ensure the safety and efficiency of fluid transportation. Its core functions can be summarized in three points:
High-speed exhaust: During the pipeline filling stage, the valve is fully open, rapidly expelling air from the pipe (exhausting up to 15% of the pipeline flow rate), preventing insufficient water output or pipeline vibration caused by air pockets.
Micro-exhaust: During normal operation, it continuously expels trace amounts of air dissolved in the water, preventing air resistance buildup that could affect system efficiency.
Negative pressure compensation: When the pump stops or power is lost, a sudden drop in pipeline pressure creates negative pressure. The valve automatically draws in air within 3 seconds, preventing pipeline deformation or rupture due to negative pressure (such as in water hammer accidents).
Typical Application Scenarios:
Clear Water Pipeline Systems (e.g., urban water supply, long-distance water transmission)
Heating Systems (central air conditioning, solar heating, underfloor heating)
Industrial Fluid Transportation (requires gas removal to ensure metering accuracy)
Composite High-speed Exhaust Valve Drawning
Composite High-Speed Air Vent Valve Structure and Principle: Dual-valve collaboration, anti-clogging design
Dual-valve combination structure
Main Air Vent Valve: Large-diameter design, responsible for high-speed air venting during the water filling stage.
Micro-Air Vent Valve: Small-diameter design, continuously venting trace amounts of air during operation.
Anti-Blow-Off Casing: Protects the float from being blown up by high-speed airflow and blocking the vent, ensuring stable valve operation under high pressure and high-speed airflow.
Three Stages of Working Principle
Water Filling Stage: The float is in the open position under gravity, venting a large amount of air until the water level in the pipe rises.
Operation Stage: The float closes the main valve as the water level rises, while the micro-air vent valve continues to operate.
Pump Shutdown Stage: The system pressure drops sharply, the float falls and opens the air inlet, completing negative pressure compensation within 3 seconds.
Key Technical Parameters
Material: Valve bodies commonly use WCB (carbon steel) or CF8 (stainless steel), suitable for clean water, raw water, and other media.
Pressure Rating: 1.6-16MPa, covering most water transmission scenarios.
Diameter Range: DN25-DN400, flexibly selectable according to pipe size.
Application Specifications for Composite High-Speed Air Vent Valves: Installation and Maintenance Points
Installation Location
Vertical Installation: Preferably choose the top of a riser or the end of a horizontal pipe to ensure gas naturally accumulates at the valve.
Gas-Liquid Separation Zone: It is recommended to install a manhole or buffer section to prevent gas and liquid from mixing and affecting air venting efficiency.
Protective Measures
Buffer Plug Valve: Required for systems with frequent water outages to prevent water flow impact from damaging internal valve components.
Insulation and Freeze Protection: When installed outdoors, insulate the valve and pipeline to prevent freezing and cracking at low temperatures.
Prohibited Scenarios: Strictly prohibited for use in sewage pipes containing solid particles to prevent impurities from clogging the air vent.
Maintenance Recommendations
Regular Inspection: Check for wear on the float and seals, and clean impurities from the vent.
Matching Isolation Valve: Allows for valve isolation during maintenance, preventing system drainage.