Q Rings vs. Square Cut Rings
Q Rings have an x-shaped profile, commonly called the X-ring, Q-ring, or by the trademarked name Quad Ring. Q Rings are four-lipped seals with a specially developed sealing profile that actually provides twice the number of sealing surfaces as a square cut ring. The four-lobed design not only provides lower fiction than an O-Ring and a square cut ring, but also, due to its square cross section, it resists spiral twist. Q Rings are available in a wide range of elastomer materials for both standard and special applications. When squeezed upon installation, they seal with the 4 small contact surfaces on the top and bottom. This contrasts with the square cut ring’s comparatively larger single contact surfaces top and bottom. Q Rings are vulcanized as a continuous ring. Their dimensions are specified with the inside diameter and the cross-section. Q Rings are supplied to the American Standard AS-568A and are completely interchangeable with O-Rings in these sizes.
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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. Twice the sealing surface means less radial squeeze is needed to create an effective seal resulting in less friction, less wear and longer service life.
Originally, square and rectangular cut rings were used in static applications as a direct replacement for O-Rings. They were considered an inexpensive, loose-tolerance alternative to molded O-Rings, though it is inferior to O-Rings in dynamic applications. Square rings can also be more difficult to install than O-Rings.
Q Rings provide a superior seal and also more advantages than the square cut ring.
Rocket Seals carries a full line of Q Rings in Buna, as well as some sizes in FKM, with a few select sizes in EPR, Silicone and other compounds. We also carry some square cut O-Rings in some standard sizes. Visit our website @ Rocketseals.com 24/7 or call us at 1 (800) 445-7803 to talk with any of our staff.