X-Rings seals for dynamic applications

The X-Rings are four lobed gaskets that can provide twice the sealing surface of a standard O-Ring. They come in a variety of elastomeric materials for standard and special applications and are suitable as sealing systems for the majority of liquids and gases. Thanks to their double-sealing action, less squeeze is required to maintain an effective seal, thus causing less friction in dynamic applications. The X-Rings are generally used in dynamic systems, but their application is still limited by pressure and velocity.
Advantages of X-Rings vs O-Rings:

  • The four-lobed configuration of the X-Ring resists distortion called "Spiral Twist" that is sometimes encountered by an O-Ring upon installation;
  • Less friction and wear which will increase seal life and lower maintenance costs;
  • Excellent sealing performance under pressure, thanks to its profile;
  • The grooves on the inside and outside diameter of the X-Ring retain lubricant thereby easing the setting in motion.

X-rings for rotary shaft

In applications with rotary shaft, the sealing ring must be installed according to the rotary sealing system principle, based on which the elastomeric ring will shrink when hot. Following standard installation procedures (inner diameter ring < shaft diameter) causes friction which will further shrink the gasket. The rotary shaft will be subject to increased pressure by the ring and the lubricant film between shaft and ring will not form properly, thus causing higher wear which will reduce seal life. To avoid such a situation, the rings diameter should be 2-5% larger than the shaft diameter.

Once in its housing, the ring is compressed in the radial direction and kept in place against the shaft by the housing walls. It will appear slightly undulated, but this improves lubrication.