The characteristic sandwich design of the gasket, with alternating combined foil layers of expanded pure graphite and intermediate layers of metal, results in ideal bonding of the material layers and ensures triple safety against leakage. The graphite provides the necessary elasticity to press the metal elements against the seat. Reliable seat tightness is achieved by the metal layers joining seamlessly to the body. 

The specially machined inner contour of the gasket has a crucial impact on the tightness achieved by the valve and can be produced with high-quality surface finishes to meet customer specifications. A wide range of stainless steels and special alloys are available as metallic materials, which can be combined with proven soft materials such as graphite, PTFE and mica. 

For critical and sensitive applications, such as use in oxygen lines, graphite-based butterfly valve seals can be manufactured with the innovative LE-SAFE technology without the use of adhesives. Furthermore, only pure graphite materials from a BAM-tested single batch are used, as well as metal materials that have been recommended for oxygen applications, such as 1.4401/1.4404, 1.4828.