In any type of system or application, choosing the components that match the specifics of the system is always critical to the operation. Unfortunately, small mistakes in the choice of a given component can lead to equipment breakdowns, reduced life cycles, or even performance issues.
In pneumatic and hydraulic types of systems, valves are essential for both control of the volume of flow of media through the system through automatic or manual control, but also for eliminating concerns with backflow through the system. These types of valves have specific pressure range settings that allow them to open and close automatically based on the pressure differences on the inlet and outlet side of the valve.
The Cracking Pressure
The cracking pressure on a valve is the lowest or the minimum pressure on the upstream or inlet side of the valve that allows the valve to open. A check valve always has a stated cracking pressure, and this pressure has to be reached before there is any flow of the media through the valve.
A low cracking pressure valve is used in systems with low pressure requirements. In other words, these check valves open or crack at a specific pressure to allow air flow at a lower pressure than may be seen in other similar sized lines and tubes.
A good example of a system that requires a low cracking pressure valve is for the pneumatic tools and devices used in a dental office. There is no need to have high pressure systems in these applications, and high pressure would be potentially dangerous and unsafe for patients.
While most low cracking pressure valves are small or miniature types of check valves, they can also be designed for other types of applications. Be sure to choose not only the right cracking pressure for the application but also the correct option in valve material and design for optimal performance and life cycle.
