As a device for quickly removing gas from pipelines, exhaust valves are essential equipment for improving the efficiency of water conveying equipment and protecting pipelines from deformation and rupture. The exhaust valve is installed at the pump outlet or in the water supply and distribution pipeline to largely eliminate the accumulated air in the pipeline and improve the efficiency of water pipes and pumps. And once negative pressure occurs in the pipeline, this valve can quickly suck in air to prevent damage to the pipeline caused by negative pressure. The exhaust valve is generally used for pipe exhaust of independent heating system, central heating system, heating boiler, central air conditioning, floor heating and solar heating system.

Precautions for setting exhaust valves:

1. The exhaust valve must be installed vertically, that is, it must ensure that the internal float is in a vertical state to avoid affecting the exhaust.

2. When installing the exhaust valve, it is best to install it together with the isolation valve, so that when the exhaust valve needs to be removed for maintenance, it can ensure that the system is sealed and water does not flow out.

3. The exhaust valve is generally installed at the highest point of the system, which is beneficial for improving exhaust efficiency.

Performance requirements for exhaust valves:

1. The exhaust valve should have a large exhaust capacity, which can quickly exhaust and restore to normal water supply capacity in a very short time when the pipeline is empty and filled with water.

2. When there is negative pressure generated in the exhaust valve inside the pipe, the piston should be able to quickly open and absorb a large amount of external air to ensure that the pipeline will not be damaged due to negative pressure. And it can expel trace amounts of air accumulated in the pipeline under working pressure.

3. The exhaust valve should have a relatively high air closing pressure, and should have sufficient capacity to exhaust the air in the pipeline in a short period of time before the piston is closed, thereby improving the water delivery efficiency.

4. The water closing pressure of the exhaust valve should not exceed 0.02 MPa, and the exhaust valve can be closed at a lower water pressure to avoid a large amount of water gushing out.

5. The exhaust valve should use stainless steel floating balls (floating barrels) as the opening and closing parts.

6. The exhaust valve body should be equipped with an anti impact protection inner cylinder to prevent premature damage to the floating ball (bucket) caused by the direct impact of high-speed water flow after a large amount of exhaust.

7. For exhaust valves with DN ≥ 100, a split structure is adopted, consisting of a large number of exhaust valves and automatic exhaust valves to meet the requirements of pipeline pressure.

8. For high flow rates, frequent start of water pumps, and operating conditions with a diameter DN ≥ 100, a buffer plug valve should be installed on the exhaust valve to reduce water flow impact. The buffer plug valve should be able to prevent a large amount of water spray without affecting a large amount of exhaust, so that the water delivery efficiency is not affected, and effectively prevent the occurrence of water hammer.