The reason why the seals have different hardness is to adapt to different working pressures. Macroscopically, the hardness of the seals suitable for different pressure ranges can be referred to the following table.
Scope of use
Suitable for low pressure working environment
Suitable for general stress work environment
Suitable for high pressure working environment
2. If you know the specific value of the working pressure of the seal, you can make a more precise choice according to the table below. However, before looking at the table carefully, please also pay attention to the gap tolerance according to the diagram on the right.