Gas injection micro-discharge valve

I. Product Introduction:
The gas-injection micro-exhaust valve, also known as the vacuum breaker, is used for pipeline exhaust. It is widely applied in independent heating systems, central heating systems, heating boilers, central air conditioners, floor heating, solar heating systems, etc. Since water usually dissolves a certain amount of air, and the solubility of air decreases as temperature rises, during the circulation process, gas gradually separates from water and aggregates to form large bubbles or even gas columns. Therefore, as long as there is water replenishment, gas will be generated frequently. At this time, the exhaust valve is needed to discharge the accumulated gas in the pipeline to ensure unobstructed flow of the pipeline medium and prevent the hazards caused by negative pressure on the pipeline due to accumulated gas.

II. Product Features:
1. The float is made of low-density PPR and composite materials, which will not deform even when soaked in high-temperature water for a long time and will not cause difficulty in float movement.
2. The float lever is made of hard plastic, and the connection between the lever and the float as well as the support is a movable connection, so it will not rust during long-term operation, which would otherwise cause system failure and water leakage.
3. The sealing end face of the lever is supported by a spring, which can expand and contract accordingly with the movement of the lever, thus ensuring sealing performance when there is no exhaust.

III. Product Principle:
It is generally installed at the highest point of the system because when gas overflows from the system, it will climb upward along the pipeline and finally gather at the highest point of the system. When gas enters the exhaust valve cavity and gathers at the upper part of the valve, as the gas in the valve increases, the gas pressure rises above the system pressure, causing the water level in the cavity to drop. The float drops along with the water level, thus opening the exhaust port. After the gas is exhausted, the water level rises, and the float rises accordingly, thus closing the exhaust port. Similarly, when negative pressure occurs in the system, the water level in the valve cavity drops and the exhaust port opens. Since the external atmospheric pressure is higher than the system pressure at this time, air will enter the system through the exhaust port, preventing the hazards of negative pressure.

IV. Performance Requirements:
1. The exhaust valve should have a large exhaust volume. When the pipeline is filled with water from an empty state, it can quickly exhaust gas within a very short time and restore normal water supply capacity.
2. When negative pressure is generated in the pipeline, the piston of the exhaust valve should open quickly to inhale a large amount of external air rapidly, ensuring that the pipeline will not be damaged by negative pressure. Moreover, it should be able to discharge the trace air accumulated in the pipeline under working pressure.
3. The exhaust valve should have a relatively high air-closing pressure. Within a short time before the piston closes, it should have sufficient capacity to exhaust all the air in the pipeline, improving water transmission efficiency.
4. The water-closing pressure of the exhaust valve should not exceed 0.02 MPa, so that the exhaust valve can close under low water pressure, thus avoiding a large amount of water gushing out.
5. The exhaust valve should use a stainless steel float (float bucket) as the opening and closing component.
6. The exhaust valve body should be equipped with an anti-shock inner cylinder to prevent high-speed water flow from directly impacting the float (float bucket) after large-scale exhaust, which would cause premature damage to the float (float bucket).
7. For exhaust valves with DN ≥ 100, a split structure is adopted, consisting of a large-flow exhaust valve and an automatic exhaust valve, to meet the requirements of pipeline pressure. The automatic exhaust valve should use a compound lever mechanism to greatly amplify the buoyancy of the float, with a low closing water level, so that impurities in water are less likely to contact the sealing surface, and the exhaust port will not be blocked, greatly improving its anti-blocking performance. Meanwhile, under high pressure, due to the boosting effect of the compound lever, the float can drop synchronously with the water level, and the opening and closing component will not be sucked by high pressure like traditional valves, thus ensuring normal exhaust.
8. For working conditions with high flow rate, frequent pump start-up, and DN ≥ 100, to mitigate water flow impact, the exhaust valve should be equipped with a buffer plug valve. The buffer plug valve can prevent large-scale water spray without affecting large-scale exhaust, so that water transmission efficiency will not be affected, and water hammer can be effectively prevented.

V. External Dimensions: