Installation of the breathing valve

There are no particular requirements for the installation of a vent valve, but the following points should be noted: 1. It should be installed at the highest point in the gas space of the storage tank. 2. When 2 breather valves need to be installed, they should be symmetrical with respect to the center of the tank roof. 3. If a nitrogen seal is also used, the interface of the nitrogen seal tube should be kept away from the interface of the breather valve, and it should be inserted into the tank by 200 mm from the top, so as to prevent nitrogen from escaping directly through the breather valve. 4. Some vent valves now come equipped with a nitrogen interface; in such cases, the nitrogen sealing pipeline can be connected directly to this interface. 5. Some vent valves now come equipped with a flame arrester, so there is no need to install an additional one. 6. If an additional flame arrester is required, connect it after the breather valve, at the end of the pipeline.

(1) The breather valve should be installed at the highest point of the gas space in the storage tank, in order to reduce material evaporation losses and to provide the most direct and largest pathway to the breather valve. Generally, for vertical tanks, the vent valves should be installed as far as possible within the central roof area of the tank. For tanks whose roofs require insulation, they can be installed near the ladder platform ； (2) When two breather valves need to be installed, they are arranged symmetrically with respect to the center of the tank roof ； (3) If a breathing valve is used on a nitrogen-sealed tank, the connection point of the nitrogen supply pipe must be kept away from the breathing valve interface, and it should be inserted into the tank from the top by about 200 mm; this prevents the nitrogen from being discharged directly once it enters the tank, thereby achieving the purpose of nitrogen sealing. Precautions for installing breather valves: With the rapid development of industry in China, breather valves are being used more and more widely in fields such as metallurgy and petrochemicals, and their stability and reliability have become increasingly important. The performance of these valves directly affects the automatic control process. This article will provide a detailed explanation of the use and maintenance of electric control valves. 1. Precautions for installation and use: For newly designed and installed control systems, to ensure that the breathing valve functions properly during operation and to maintain the safe operation of the system, it is necessary to first check whether the markings on the valve match the design specifications before installing it. At the same time, the following items should also be debugged. Basic error limit ； Total journey deviation ； hysteresis ； dead zone ； Leakage amount (performed in applications with strict requirements). If a major overhaul is carried out on the breathing valve in the original system, in addition to verifying the items mentioned above, it is also necessary to check the sealing integrity of areas such as the packing gland and connections of the old valve. In practical use, many problems with breathing valves are not caused by the quality of the valves themselves, but rather by improper installation or use – factors such as an inappropriate installation environment, incorrect location or orientation, or unclean pipelines. Therefore, the following points should be taken into consideration when installing and using breather valves: The HX series of breather valves are field instruments, and the operating environment should have a temperature range of –25 to 60°C with a relative humidity of ≤95%. If it is installed in an outdoor or high-temperature environment, waterproofing and cooling measures should be taken. In areas with a source of vibration, one should stay away from it or take additional vibration prevention measures. Breather valves should generally be installed vertically; in special cases, they can be tilted. If the tilt angle is large or if the valve’s own weight is too great, support elements should be added to protect the valve. Pipes equipped with 24/7 flame arrestor breather valves should generally not be placed too high above the ground or floor. When the pipe height exceeds 2 meters, a platform should be provided as much as possible to facilitate the operation of the handwheel and ease maintenance. Before installing the all-weather flame arrestor vent, the pipeline should be cleaned to remove dirt and slag. After installation, to ensure that no impurities remain inside the valve body, the valve should be cleaned again; that is, all valves should be opened when the medium is introduced, to prevent impurities from getting stuck. After using the handwheel mechanism, it should be returned to its original neutral position. To enable the production process to continue in the event of a failure or maintenance of the breather valve, a bypass line should be provided for it. Special attention should also be paid to whether the installation location of the breathing valve meets the requirements of the process. The installation of the electrical components of the all-weather explosion-proof breather valve shall be carried out in accordance with the relevant construction requirements for electrical equipment. In the case of flameproof products, they shall be installed in accordance with the requirements of the \"Code for Installation of Electrical Equipment in Explosive Atmospheres\". If the wires on site are of the SBH type or other six-core or eight-core rubber-insulated cables with an outer diameter of around Φ11.3 mm. During maintenance, it is strictly prohibited to power on and open the cover in explosive environments, as well as to pry at the flameproof surface. At the same time, avoid damaging or scratching the flameproof surface during disassembly and assembly, and restore it to its original flameproof condition after maintenance. After disassembling and repairing the reducer of the actuator, attention should be paid to lubrication by adding oil; low-speed motors generally should not be disassembled, cleaned, or lubricated. After assembly, it is also necessary to check whether the valve position matches the indication of the valve opening degree. 2. Common failure locations and cause analysis: The performance of the breathing manhole directly affects the quality of operation of the entire control system. Since the breathing manhole is in direct contact with the medium being handled on-site, and operates in a very harsh environment, it is prone to various failures. During the production process, in addition to promptly resolving these faults, regular maintenance and periodic inspections are also necessary. Especially for breathing valves used in particularly harsh environments, greater attention should be paid to maintenance and regular inspections.

I found it extremely useful; the two people above provided very detailed explanations.

(1) The breather should be installed at the highest point of the gas space in the storage tank, in order to reduce material evaporation losses and to provide the most direct and largest path leading to the breather valve. Generally, for vertical tanks, the breather valve should be installed as close as possible to the central roof area of the tank. For tanks whose roofs require insulation, it can be installed near the ladder platform ； (2) When two breather valves need to be installed, they should be arranged symmetrically with respect to the center of the tank roof ； (3) If a breathing valve is used on a nitrogen-sealed tank, the connection point of the nitrogen supply pipe should be placed far away from the breathing valve interface, and it should be inserted into the tank from the top by about 200 mm; this prevents the nitrogen from being discharged directly once it enters the tank, thus achieving the purpose of nitrogen sealing.

From the forum, I saw that the breather valve can be installed in reverse, but this wasn’t mentioned here. Please advise

Could you tell me where these requirements come from? Thank you! Is it that specification or standard?

It’s very useful! It is possible to identify some potential problems