Application Example: Quad-Ring® Brand Face Seal
Application description: Cover for a Static Pressure Vessel, U. S. Customary Units (inches)
- Inside pressure of 50 psi
- Bore diameter 0.500" ±0.005
- Desired Maximum groove OD of 0.750" -0.005/+0.000
- 0.103" cross-section Quad-Ring® Brand seal
- Cover is flat
|Ring Size||Cross Section||AXIAL Static Recommended
Gland Depth "C"
|RADIAL Static Squeeze Groove
With "D" +0.005/-0.000
|Q4102 - Q4178||0.103 ±0.003||0.089||0.115|
- Determine the groove depth:
Since the cover is flat, the groove depth is simply the gland depth. For this static application, the recommended gland depth from the table is 0.089.
Groove Depth = Gland Depth = 0.089 -0.002/+0.000
For the purpose of this example, a tolerance on this dimension of -0.002/+0.000 is assumed.
- Calculate the groove inside diameter.
From the table, the groove width for a 0.103 cross-section seal is 0.115 -0.000/+0.005.
Groove I.D. = Minimum Groove O.D. - (2 x Groove Width)
= 0.745 - (2 X 0.115)
= 0.515 -0.005/+0.000
For the purpose of this example, a tolerance on this dimension of -0.000/+0.005 is assumed.
- Calculate the Minimum Gland Volume:
Minimum Gland Volume = ((Min Groove O.D. - Max Groove I.D.) / 2) x Min Gland Depth
= ((0.745 - 0.515 )/2) X 0.087
= 0.010 in2
- Calculate the Maximum Quad-Ring® Brand Seal Volume:
Maximum Quad-Ring® Brand
Seal Volume = (Max Quad-Ring® Brand Cross-section)2 X 0.8215
= (0.106)2 X 0.8215
= 0.00923 in2
- Compare the Minimum Gland Volume to the Maximum Quad-Ring® Brand Seal Volume
In this application the maximum seal volume is less than the minimum gland volume, so the seal should function satisfactorily.
- Calculate the Minimum and Maximum Seal Squeeze
a. Max Seal Squeeze = 1 - (Min Gland Depth / Max Seal Cross-section
= 1 - (0.087 / 0.106)
= 0.179 = 17.9%
b. Min Seal Squeeze = 1 - (Max Gland Depth / Min Seal Cross-section)
= 1 - (0.089/.100)
= 0.11 = 11%
Therefore, sufficient squeeze should exist to seal this application.
- Select the Seal Size
Refer to the Selection Guide and turn to the section which lists the seals having a 0.103 cross-section. Since this is an internal pressure application, the seal OD should always be seated against the groove OD, which has a maximum size of 0.750. Since the Selection Guide Table provides seal ID information, determine the minimum required ID by subtracting the minimum seal cross-section:
Min ID= 0.750 - 2 x Min seal Cross-section = 0.750 X (2 X 0.100) = 0.550
A 4114 seal would always have a minimum ID greater than 0.550.