How much squeeze should an O-ring have?

To provide an effective seal, the O-ring’s inside diameter (I.D.) must be smaller than the piston groove diameter, so that the O-ring is slightly stretched, fitting snugly in the groove. This stretch should be between 1%-5% with 2% as the ideal in most applications. A stretch greater than 5% is not recommended.

How much force does it take to compress an O-ring?

103” cross section is approximately 9 to 18 pounds per linear inch of O-ring. For the same amount of squeeze on a . 070” O-ring, the range is roughly 5-18 pounds per linear inch of O-ring circumference.

What do you call the squeeze on an O ring?

If the squeeze is on the inner and outer surfaces of the O-ring, as in piston or rod seals, it is referred to as RADIAL squeeze. To obtain the correct amount of squeeze for optimum O-ring sealing, careful consideration must be given to the size of the O-ring in relation to the size of the glandular space into which the O-ring is being installed.

How to calculate the O-ring seal squeeze ratio?

The equation for calculating compression is (O-ring CS – Gland height) / O-ring CS. For a radial seal application, gland height is calculated by (Bore diameter – groove diameter) / 2. Parker OES does not have data for fluid pressure from 8000 – 15000psi.

Is there a relationship between O-ring Squeeze and load force?

At 40 percent, pinching of the O-ring between mating components was difficult to avoid, while at 25 percent installation pinching was virtually eliminated. As Figure 3 shows, the relationship is not linear between the amount of squeeze and the compressive load force required to maintain the squeeze.

When do you stop squeezing the O-ring seal?

At the 40 percent level, pinching is difficult to avoid while pinching is eliminated at the 25 percent level. The force that the squeezed elastomer exerts against the mating hardware, creating the seal, tends to decay with time. When that force decays entirely, the O-ring will retain its squeezed shape even when it is no longer squeezed.