The sealing principle of the Quad-Ring/X-Ring is nearly the same as the O-ring sealing. The initial sealing is achieved by the diametrical squeeze in a right angled groove. The system pressure itself creates a positive sealing force.
Following are some advantages of Quad-Rings/X-Rings:
With X-Rings the standard grooves are deeper In comparison with O-ring glands. So the diametrical squeeze is lower than with O-rings. This makes dynamic sealing possible with reduced friction.
The four lips of the X-Ring create more sealing capacity and at the same time a groove for lubrication,which is very favourable for dynamic sealing.
The most important advantage of the X-Ring is the high stability for dynamic applications. In the situation that an O-ring rolls in the groove and creates torsion, a X-Ring will slide with no negative results.