In addition to the general requirements for sealing ring materials, the following conditions must also be observed for the sealing ring:
(1) Flexible and resilient;
(2) Appropriate mechanical strength, including expansion strength, elongation and tear strength.
(3) Stable in performance, not easy to swell in the medium, and low in thermal shrinkage (Joule effect).
(4) easy processing and molding, and can maintain precise dimensions.
(5) Do not corrode the contact surface and do not contaminate the medium.
The most suitable and most commonly used material for meeting the above requirements is rubber, so the sealing ring is mostly made of rubber material. There are many varieties of rubber, and there are new types of rubber. When designing and selecting, it is necessary to understand the characteristics of various rubbers and make reasonable choices.