The type of cut, the cut clearance and the pre-tension determine the extent to which the piston ring or metallic seal is able to seal. The pre-tension refers to the space between the cut ends before installation. The cut clearance is the space between the cut ends after installation, in other words, when the piston ring is mounted in the application. The cut clearance determines, among others, the leakage. If the cut clearance is too large, additional leakage can/will occur. Leakage will decrease the efficiency of the piston ring or seal and shorten its lifespan.
An insufficient cut clearance can also cause problems. If the piston ring or metallic seal expands due to friction or ambient temperature and the clearance available in the cut is insufficient, this could lead to uneven pressure. When the heat increases this much, the piston ring or metallic seal will expand further, creating even more friction and leading to damage to the counter material.
The degree to which the cut needs to seal differs from application to application. The images below show various cut types. If you have any questions about the function of the cut, or if would you like to know which cut would be best for your application, please feel free to contact us.
