O-rings can be installed in three different ways.
1. Flange gasket
2. Piston seal
3. Rod seal
Definition of a piston seal: The groove is located in the inner part of a piston, for example, and the O-ring inside is pressed radially (pressing line is at 90° to the axis).
In addition to the type of installation, a distinction is also made between static and dynamic applications.
Static = Without movement
Dynamic: With movement
Piston seals are very common in hydraulic cylinders, for example. Accordingly, the majority of piston seals are used as dynamic seals.