Some of the most demanding applications for any type of valve are found in the chemical processing industry. Parts and components in these systems have to be extremely resistant to operating in high and low temperatures as well as with media that can be extremely corrosive and reactive.
The use of a chemical check valve in a system is often critical, for both safety, as well as to avoid possible dangerous operating conditions. These valves have to be selected to not only handle the physical conditions of chemical processing systems but to also have a long-life cycle and high levels of reliability.
The Important Features of a Check Valve
A chemical check valve, like all other types of check valves, is designed to allow the flow of the media in one direction only. The pressure of the media keeps the check valve open and the single direct flow working. Choosing the correct size of valve will be a factor of the pressure range throughout the system, with the highs and lows critical to consider.
Should the pressure drop the ball, gate, diaphragm or other component will immediately engage, preventing any backflow through the system. It is essential that these valves operate consistently and reliability as they may be in the open position for extended periods of time.
Other types of chemical check valve options are frequently used in some systems. A good example of this is a check valve that is used in a nitrogen purge of a system. The check valve allows the nitrogen to be introduced into the system but then, as the pressure on the nitrogen drops, the valve immediately closely, eliminating and backflushing of the chemical into the nitrogen lines.
There are many different uses of these check valves in chemical processing systems. They can be found on vacuum lines, evaporators, condensate returns and even on compressor discharge lines.
