Why the exhaust valve must be installed in the water supply pipeline?

Why the exhaust valve must be installed in the water supply pipeline?

When the water pump stops working, negative pressure will be generated at any time, and the floating ball will drop at any time, and a large amount of suction will be performed to ensure the safety of the pipeline. In the exhaust state, the buoy pulls down one end of the lever due to gravity. At this time, the lever is in a tilted state, and a gap appears in the contact part between the lever and the exhaust hole.

The air is discharged from the vent hole through this gap. With the discharge of air, the water level rises, and the buoy floats upward under the buoyancy of the water. The sealing end surface on the lever gradually presses the vent hole until the entire vent hole is completely Blocked, the exhaust valve is completely closed at this time.

Precautions for setting the exhaust valve:

1. The exhaust valve must be installed vertically, that is, it must be ensured that the buoy inside it is in a vertical state, so as not to affect the exhaust.

2. When installing the exhaust valve, it is best to install it together with the block valve, so that when the exhaust valve needs to be removed for maintenance, the airtightness of the system can be ensured and the water will not flow out.

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

The function of the exhaust valve is mainly to remove the air inside the pipeline. Because there is usually a certain amount of air dissolved in water, and the solubility of air decreases with the increase of temperature, so that the gas gradually separates from the water during the water circulation, and gradually gathers together to form large bubbles or even air columns. Because of the replenishment of water, gas is often generated.

Generally used in independent heating systems, central heating systems, heating boilers, central air conditioning, floor heating and solar heating systems and other pipeline exhaust.

Performance requirements of the exhaust valve:

1. The exhaust valve should have a large exhaust volume. When the empty pipe is filled with water, it can quickly exhaust and return to the normal water supply capacity in a very short time.

2. When the exhaust valve has negative pressure in the pipe, the piston should be able to open quickly and quickly suck in a large amount of outside air to ensure that the pipeline will not be damaged by negative pressure. And under the working pressure, the trace air accumulated in the pipeline can be discharged.

3. The exhaust valve should have a relatively high air closing pressure, and within a short period of time before the piston closes, it should have sufficient capacity to discharge the air in the pipeline to improve the water delivery efficiency.

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

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

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

7. The exhaust valve with DN ≥ 100 adopts a split structure, which is composed of a large number of exhaust valves and automatic exhaust valves to meet the requirements of pipeline pressure. The automatic exhaust valve should adopt a double lever mechanism, so that the buoyancy of the floating ball can be greatly amplified, and the closing water level is low, impurities in the water are not easy to contact the sealing surface, the exhaust port will not be blocked, and its anti-clogging performance can be greatly improved.

At the same time, under high pressure, due to the force of the double lever, the floating ball can drop synchronously with the water level, and the opening and closing parts will not be sucked by high pressure like traditional valves, so as to exhaust normally.

8. For the working conditions of high flow rate, frequent pump start, and caliber DN≧100, in order to slow down the impact of water flow, the exhaust valve should be equipped with a buffer plug valve. The buffer plug valve should be able to prevent a large amount of water spray but not affect a large amount of exhaust, so that the water delivery efficiency will not be affected, and the water hammer can be effectively prevented.