The Sewage Composite Exhaust Valve (SCAR Composite Exhaust Valve) is an exhaust equipment for sewage pipeline projects, primarily installed at pump outlets, distribution pipelines, or local high points of pipelines to expel accumulated gases within the pipes, preventing airlock and avoiding pipeline vibration and cracking. The valve is available in models such as SCAR and SCARX, suitable for media including clean water, sewage, and silt-laden waters, and applicable to scenarios such as urban and industrial sewage treatment plants. The valve body is cylindrical in shape, made of HT200 cast iron, and internally equipped with a 304 stainless steel float ball, lever mechanism, and nitrile rubber sealing components. Its operation is divided into three stages: the valve disc opens to release a large amount of exhaust gas during water filling; after the water level rises, the float ball closes the main exhaust port; during normal water transport, a small amount of gas is排出 through small holes, and air is吸入 to protect the pipeline when the pipeline is under negative pressure. Key parameters include nominal pressure of 1.0 MPa, applicable temperature range of 0-80°C, and flange connection specifications covering DN50-DN200. The improved model uses the lever mechanism to position the float ball to prevent debris entanglement, and the accompanying maintenance valve ensures easy maintenance.

Working Principle

As water begins to fill the pipe, the valve disc is in the open position, venting air in large quantities. Once the air is exhausted, the valve is filled with water, the float rises and closes the valve disc, halting the venting. When water is normally flowing through the pipe, if a small amount of air accumulates inside to a sufficient degree, the water level inside the valve drops, and at this point, the air is expelled through small holes. When the pump stops, the water in the pipe may empty or a vacuum may be created, at which time the plug head quickly opens,吸入 air, ensuring the safety of the pipeline.

Note: The exhaust valve must not experience a pressure below 0.02 Mpa during use; otherwise, it may leak. A valve must be provided for maintenance purposes.

Primary Technical Parameters

Nominal Pressure: 1.0 Mpa

2. Nominal Pipe Size: DN25 to 200mm for flange connection

3. Applicable Media: Water, Wastewater

4. Operating Temperature: 0-80℃

5. Flange Standard: GB/T 17241.6

6. Test Standard: GB/T 13927

7. Valve Body: HT200

8. Buoy and Check Valve: 304 Stainless Steel

9. Sealing Materials: Nitrile Rubber