What You Should Know About Breather Valves

You can regard the breather valve as a pressure relief valve. Usually, it is used as a protective device in atmospheric and low-pressure storage tanks.

The valves can prevent an explosion in tanks due to the increased pressure. Moreover, they can also restrict implosion that can arise during the filling or emptying of the storage tanks. However, the valves do not allow the vapour to go away until the tank reaches the preset pressure.

Breather valves can also protect the storage tank when the tank is in out-breathing mode. They save the tank by controlling the in-breathing and out-breathing apart from during pressure increase.

While breathing in and out, a tank needs a proper vent that can release the excess air that comes into play during the loading and unloading operations.

Also, breather valves can protect tanks from rupture due to overpressure or against collapse caused by vacuum.

A proper venting system can protect storage tanks from the propagation of flames, which can cause an explosion. For example, a storage tank carrying flammable liquid needs to breathe and reduce the evaporation loss, and breather valves can help the tank maintain balance.

Functions of breather valves:

• Reduction of vapour loss from storage tanks
• Prevention of pressure and vacuum that exceeds the tank limit
• Prevention of flammable conditions
• Protecting the contents of the tank from moisture intrusion.

Selecting a Breather Valve

When you select a breather valve, you should ensure that it can reduce the moisture entering the container. The primary function of these valves is to protect the tank from excessive pressure and vacuum. As such, the valves should remain sealed except during the airlift and in extreme temperature conditions.

It will help if you explore certain factors about the container to select the best breather valves, such as:

• Maximum pressure and vacuum that the tank can withstand
• The tank volume
• How quickly the pressure change can take place
• The temperature change that can happen during the storage
• Relative humidity and temperature of the storage area

The Types of Breather Valve

Breather valves are of the following types:

Pressure or Vacuum Relief Valve

The valves can be a single unit or two-unit, in two-unit. At the same time, one unit controls the vacuum, the other controls the pressure.

Pilot Operated Relief Valve

These valves protect the tank from low pressure and vacuum. As a result, they can do away with the need for overpressure design requirements.

Air Operated Relief Valve

These valves can reduce evaporation loss and have high efficiency. Usually, these valves are used where polymerization and crystallization can take place—the valves lower content loss from a tank.

Emergency Vent Valve

These valves are used for emergency conditions such as fire outbreaks or temperature rise due to chemical reactions. In such situations, the evaporation rate would be high, and that increases the pressure and temperature. And, standard breather valves cannot handle such high temperature and pressure. So, emergency vent valves are necessary.

Other important devices are level indicators used to measure fluid levels in tanks, drums. pressure vessels etc

Conclusion

We believe that this article has helped you understand what a breather valve is and its uses. Moreover, it can also help you select the right breather valve for your business.