R octagonal gasket refers to the metal gasket of octagonal-shaped
section by processing metal materials. It is of pressure energized
seal in radial direction. The average diameter of the gasket is
slightly larger than the average diameter of the gasket groove. The
angle between ring gasket and bevel face of gasket groove is around
23. It has good sealing as the contact between gasket and the ring
joint faces, especially the outside face, and is pressed tightly to
keep good sealing performance.