In urban water supply pipelines, air intake and exhaust valves are generally installed at high positions within the pipelines. Due to the complex terrain and numerous obstacles such as rivers and sewers, More than 30 exhaust valves have been installed along the line. The valve body is made of gray cast iron, and the internal float ball is made of engineering plastic, which is bonded together by two hemispheres. The surface of the bonding area is rough, and the plastic is prone to aging and deformation, resulting in the valve seat and float.

In practical applications, the diameter of the float ball blown by air can be determined. Water is more likely to move a float ball with a larger diameter than air. When this ratio is combined with an appropriate conical Angle at the valve inlet, the impact airflow that is ejected will generate a greater suction force than the collision force, causing the float ball to float downward. As the jet speed increases, so does the suction force. Therefore, any speed of airflow can be smoothly discharged.

The performance and features of dynamic high-speed intake and exhaust valves

In water transmission pipelines, the exhaust volume of the intake and exhaust valves is very important. For instance, if the supply is too small, it often takes a long time to restore the original water supply capacity when water is cut off and then restored. However, if the supply is large, the normal water supply capacity can be restored in a very short time.

The dynamic high-speed intake and exhaust valves far exceed the industry standard requirements. Compared with the traditional large-diameter intake and exhaust valves, the dynamic type is significantly superior in performance and can be converted according to 80% of the exhaust volume. Therefore, whether it is exhaust or intake, it is superior to the traditional intake and exhaust valves.

In addition to the general gas of the intake and exhaust valves, there are three other ways to judge the performance of the intake and exhaust valves. The magnitude of the pressure of the air closure valve; When water overflows from the pipe, can you hold down the floating ball? Can it be sealed without leakage at low pressure (0.02Mpa)?

For dynamic high-speed intake and exhaust valves, due to the adoption of float balls with special diameters and masses and valve inlets with appropriate conical angles, the structure is simple and reasonable, and there will be no phenomenon of float ball movement getting stuck in resistance. Repeated tests have shown that the float ball can close the window smoothly under any water pressure. At the same time, a double-line sealing structure is used to ensure good sealing. During the experiment, when the low pressure is 0.018Mpa, the float ball can closely adhere to the valve to prevent leakage.

The application of Dynamic high-speed intake and exhaust valves

Hammers can be destructive in long-distance water transmission pipelines. Therefore, the air intake and exhaust valves installed are equipped with airbags to ensure stable operation and prevent direct or indirect hammers. After the water transmission pipeline is determined, the pressure increase P of the hammer mainly increases with the increase of the flow velocity Vo. In actual engineering design, the flow velocity can be appropriately reduced. That is to say, by increasing the diameter of the pipe, the danger of hammering can be reduced. However, if the gas in the pipeline cannot be discharged in time, some parts will become air pockets, the flow area will decrease, the flow rate will increase, the hammer will increase, and the danger of the hammer will also increase. Even more harmful water vapor may form to fill the hammer. Therefore, appropriate exhaust valves should be installed at local key positions to discharge the gas in the pipeline ahead of the water flow.