quad rings

Quad-Ring® Seals are four-lipped seals with a specially developed sealing profile that actually provides twice the number of sealing surfaces as an O-ring. The four-lobed design not only provides lower fiction than an O-ring, but also, due to its square cross section, it resists spiral twist. Quad-Ring® Seals are available in a wide range of elastomer materials for both standard and special applications. Quad-Ring ® Seals are vulcanized as a continuous ring. Their dimensions are specified with the inside diameter "d1" and the cross-section "W." Quad-Ring® Seals are supplied to the American Standard AS-568A and are completely interchangeable with O-rings in these sizes. Quad-Rings® Seals are available in all standard O-Ring sizes from 1/32" to 26", as well as custom seals for unique applications.

Features:
• High Sealing Effect - There are two sealing surfaces to give a positive seal with less friction. 
  Due to an improved pressure profile over Quad-Ring© Seal cross-section, a high sealing effect
  is achieved.
• Avoiding Spiral Twist - To minimize breakaway friction, an O-Ring groove must be wide enough
  to allow rolling or twisting of the seal. In the long stroke of a reciprocating seal application, this
  twisting action can strain and eventually tear the rubber, causing a failure mode known as
  spiral  twist. To prevent spiral twist, the Quad-Ring® seal’s four-lobed configuration is designed
  to withstand the distortion and extrusion often caused by high or pulsating pressure. To
  accommodate these forces, a Quad-Ring® seal uses a narrower groove than a comparable O-
  Ring seal.

• Longer Seal Life - Because less-squeeze means less friction with the four-lobe design, seals
  last longer. This means equipment in which the Quad-Ring® seal is installed will operate
  longer and require less maintenance.
• No Parting Line on Sealing Surface - Unlike O-Rings, where partitioning lines are on the
  sealing surface, Quad-Rings® seal’s parting lines lie between the lobes, away from the sealing
  surface. This design eliminates the problems of leakage resulting from a parting line’s irregular
  surface. The recessed mold parting line provides no flash or parting line on the surface of the
  seal and ensures "zero leakage." What's more, a lubricant reservoir formed between the
  sealing lips improves performance at start-up.