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The all-weather breather valve is a gravity-type structure with overlapping valve seats. It is characterized by a soft contact between the valve disc and the valve seat, with an air cushion in place, which ensures good airtightness and prevents frosting or freezing; it is suitable for use in cold regions. It combines the traditional tank vent valve with the tank flame arrester into one unit, with the flame arrester placed at the inlet of the vent valve, thereby completely preventing any source of fire from entering the vent valve housing. It features a small size, light weight, compact structure, high air flow capacity, and low leakage levels; it also has excellent sealing properties. Especially during work at heights, it is very convenient to inspect and clean the flame arrestor disc as well as the positive and negative pressure valve discs inside this combined vent and flame arrester unit. The all-weather breathing valve is installed on the top of the storage tank; it helps to manage the positive and negative pressures inside the tank, ensuring that there are no obstacles to the flow of liquid in and out of the tank. When liquid is poured into the tank, a large amount of gas is expelled outward (this is known as positive pressure). When the liquid in the tank is discharged outward, air from the outside must be drawn into the tank (this is known as negative pressure). If the breathing valve closes automatically when operation stops, it prevents the liquid and gas inside the tank from leaking out, thus ensuring the quality of the liquid contained within the tank. First, the application range of the all-weather breather valve: The new all-weather breather valve is suitable for storage tanks containing Class A oils with a flash point below 28 °C and Class B oils with a flash point below 60 °C, such as gasoline, benzene, toluene, kerosene, light diesel, engine oil, crude oil, and other similar chemical products. The all-weather breather valve can be used in conjunction with the ZGB corrugated flame arrester. Second, 24/7 maintenance of the breathing valve: To ensure safe use of the breathing valve around the clock, it is necessary to check in advance whether the guide rod and valve disc are flexible before use. For all-weather breather valves, it is necessary to regularly check – within 6 months – whether the positive and negative valve discs function properly, and whether there is any damage to the contact surfaces of these discs; any damage found must be repaired immediately. After the maintenance is complete, if everything is normal, it can be used again. Third, the performance and features of the all-weather vent valve: The casing of the new all-weather vent valve is made of stainless steel, cast steel, and aluminum alloy, offering excellent corrosion resistance ； Simple structure, easy to maintain, safe and convenient ； The performance of the new all-weather breathing valve fully meets the requirements specified in the standard SY7511-87 issued by the Ministry of Petroleum Industry. The valve disc is made of PTFE material, offering resistance to low temperatures and excellent freeze-proof properties ； A breathing valve is a type of safety valve; it is a ventilation device installed on the top of storage tanks to maintain normal pressure inside the tank, preventing damage to the tank caused by excessive pressure or vacuum. It also helps to reduce vapor loss from the liquid. Breathing valves are usually used in conjunction with flame arresters. Today, I would like to recommend vent valve technology to everyone. I’m sharing three excellent articles provided by Sanjing Valves, in the hope that they will help everyone understand and learn more about vent valve technology! First, the characteristics of a breathing valve: The valve body of a breathing valve can withstand 0. With a water pressure of 2 Mpa, there is no penetration or deformation. The low-temperature resistance of the breathing valve: when the relative air humidity is above 70% and the minimum temperature is -30°C, after 24 hours of freezing, the opening pressure of its valve disc meets the requirements for operating pressure (with a permissible pressure difference of ±20 Pa). Second, classification of breather valves: The first type releases air when a certain pressure is reached, either by exhaling or inhaling ； Another option is to design it to breathe out only, which can be understood as using two check valves with appropriate pressures in place. The second type of vent valve is similar to a one-way check valve; it allows air to be exhaled outward but not inhaled inward. When the pressure inside the system increases, gas is released outward through the vent valve, thereby maintaining a constant pressure within the system. Storage tanks for toxic substances are either without breather valves, or equipped with treatment devices such as activated carbon filters. Breather valves are generally used on storage tanks at normal or low pressure; that is, only tanks at normal and low pressure have tank breathing emissions, while high-pressure tanks have no emissions, resulting in no breathing losses or operational losses. The main emissions from fixed-roof tanks are divided into breathing losses and operational losses. Third, the working principle of the breather valve: A breather valve uses a spring-loaded valve plate, and breathing occurs depending on the positive or negative pressure. The breather valve should have the function of releasing both positive and negative pressures; specifically, when the container is under positive pressure, the breather valve opens to allow gas to escape and thereby relieve that positive pressure ； When the container is under negative pressure, the breather valve opens to draw in gas and relieve the negative pressure. This ensures that the pressure remains within a certain range, thereby guaranteeing the safety of the container. Fourth, the method for selecting a breathing valve: 1. Consider the requirements regarding the installation location and temperature range; for example, in cold regions, all-weather breathing valves should be used, while those to be installed in pipelines should be pipeline-type breathing valves. 2. The control pressure of the mechanical breathing valve should be appropriate to the relevant pressure-bearing capacity. 3. The specifications of the mechanical breathing valve shall meet the requirements for the maximum flow rate of breathing gases in and out of the oil tank. Fifth, the following points should be noted regarding the installation and maintenance of vent valves: All types of vent valves should be installed vertically. There should be no resistance at the outlet of the breather valve to prevent pressure buildup. The breathing valve should be tested specifically before installation, and its airtightness should be checked. Breath valves in use should be inspected regularly. Sixth, instructions for using the breathing valve: The breathing valve is installed on the top of the storage tank; it serves to handle gases with positive or negative pressure inside the tank, ensuring that the flow of liquid in and out of the tank is not hindered. When liquid is poured into the tank, a large amount of gas is expelled outward (this is known as positive pressure). When the liquid in the tank is discharged outward, air from the outside must be drawn into the tank (this is known as negative pressure). If the breathing valve closes automatically when operation stops, it prevents the liquid and gas inside the tank from leaking out, thus ensuring the quality of the liquid contained within the tank. Breather valves are used on oil and liquid tanks to release positive and negative pressure gases from within the tank, thereby facilitating the inflow and outflow of liquids in the tank. If a breather valve is not installed on the tank, there will be certain obstacles to the inflow and outflow of liquid inside the tank, which can likely lead to deformation and vibration of the tank. This product features rational design, a simple structure, and ease of use; it is an essential item for storage tanks and cannot be omitted. Seventh, operating pressure of the breathing valve: Class A – positive pressure: 355 Pa (36 mm water column); negative pressure: 295 Pa (30 mm water column). Class B – positive pressure: 980 Pa (100 mm water column); negative pressure: 295 Pa (30 mm water column). Class C – positive pressure: 1765 Pa (180 mm water column); negative pressure: 295 Pa (30 mm water column)