Precautions for using breather valves

A breathing valve, also known as a pressure/vacuum breathing valve or safety breathing valve, is a safety device used to prevent storage tanks from being damaged due to excessive differences in internal and external pressures. They are typically installed on storage tanks used for storing volatile liquids in industries such as petroleum and chemicals; they prevent overpressure or vacuum conditions in the tanks due to gas expansion or contraction, and help reduce vapor loss of the liquid medium. ### Structure of a breathing valve A breathing valve typically consists of the following main components: 1. **Valve body**: This is the outer casing of the entire breathing valve, and it is usually made from corrosion-resistant materials such as aluminum alloy or stainless steel. 2. **Intake valve**: When the pressure inside the tank drops to a certain level (vacuum pressure), the intake valve opens, allowing outside air to enter the tank and preventing it from deforming due to the internal pressure being lower than the external pressure. 3. **Vent valve**: When the pressure inside the tank rises to a certain level, the vent valve opens to release the gas from the tank, preventing it from exploding or deforming due to internal pressure exceeding the design limit. 4. **Valve disc and seat**: The valve disc is pressed against a seat equipped with a pressure mechanism such as a spring or weight, to keep the valve properly closed. 5. **Spring or weight**: Used to provide the force that closes the valve disc; the preset pressure determines the opening pressure point of the valve. ### Performance of breather valves 1. **Pressure regulation**: Breather valves typically come with adjustable pressure settings, namely the pressure release value and the vacuum intake value, which can be adjusted according to actual needs. 2. **Sealing performance**: Ensure reliable sealing until the set pressure and vacuum levels are reached, thereby preventing leakage of the medium. 3. **Response sensitivity**: It can quickly respond to changes in pressure within the storage tank, enabling timely opening or closing. 4. **Corrosion resistance**: Depending on the storage medium, the material of the breathing valve should possess good chemical resistance and corrosion resistance. ### Precautions for use 1. **Proper installation**: Follow the manufacturer’s instruction manual to ensure that the breathing valve is installed correctly, avoiding reverse installation. 2. **Set pressure**: The opening pressure and vacuum value must be set correctly based on the design pressure of the tank and the properties of the medium stored therein. 3. **Regular inspections**: Regularly inspect and maintain the breathing valve to ensure its proper functioning, including checking components such as springs, valve discs, and seals. 4. **Cleaning and maintenance**: Keep the inside and outside of the breathing valve clean to prevent the valve from getting stuck or its sealing performance from declining due to dirt or deposits. 5. **Replace parts**: If wear or damage is detected, replace the parts promptly to prevent the valve from failing. 6. **Prevention of freezing**: In cold climates, it is necessary to prevent freezing inside the breathing valve; freezing can cause the valve to fail to open or close properly. 7. **Safety Protection**: Ensure that adequate safety measures are in place in the surrounding area to prevent harm to operators or equipment in the event of an emergency release. 8. **Compliance with regulations**: Adherence to relevant safety and environmental standards or regulatory requirements, such as API, OSHA, etc. In summary, a vent valve is an important device for ensuring the safety of storage tanks and reducing medium loss. Proper installation, maintenance, and use are essential for its proper operation. .

See: Uses and working principle of breathing valves: https://bbs.hcbbs.com/forum.php?mod=viewthread&tid=1924819&shareuid=301199. Working principle of breathing valves: https://bbs.hcbbs.com/forum.php?mod=viewthread&tid=894073&shareuid=301199. Animated explanation of the working principle of breathing valves: https://bbs.hcbbs.com/forum.php?mod=viewthread&tid=328745&shareuid=301199