|Hardness||20 to 90 Shore A|
The packing set comprises an endless U-ring firmly supported by a header ring. The lips of the U-ring are slightly flared to provide an interference fit for initial sealing. When system pressure is applied, the sealing force is increased significantly by reaction within the tongue-shaped cavity of the U-ring.
Under slight axial compression, the header ring also spreads the U-ring lips slightly to improve low pressure sealing efficiency.