Selecting the correct seal for a particular function depends upon many factors. 

The main factors are outlined below:

• The medium in which the seal will be working
• The system pressure
• The operating temperature
• The possibility of "shock-loading" pressure
• The speed, length and frequency of stroke
• The matching finish of the cylinder dynamic surfaces

The type of application:

• Constant pressure, as in mining roof supports
• Pulsating pressure, primarily encountered in single-acting cylinders
• Altering pressure, encountered only with double-acting seals such as that in earth-moving machinery
• The type of housing, whether one-piece or two-piece design