Design category for seals with a block-like body and a less pronounced sealing edge. A characteristic feature is how the preload is applied not only by the sealing lips, but also by the body of the seal becoming deformed.
Compact seals are often combined with guide elements to form piston seals. Compact seals for piston rods are often installed with a supporting ring (back ring) in order to improve gap bridging. Two-part compact seals are also used quite often. These types of seals are elastomer/energised plastic faced seals. They consist of a sealing ring (generally with bronze or carbon-filled PTFE) which is subjected to a preload by an elastically deformed O-ring The installation spaces for the piston and rod are set out in the DIN 7425 standard (Figure K 22).
Figure K 22: Two-part compact seals fit inside uniform installation spaces in accordance with DIN/ISO 7425.