**Application description: Water faucet valve, U. S. Customary Units (inches)**

- .25" dynamic stroke

- Rod (shaft) diameter: .374" ±.003

- Bore diameter: .385" ±.003

- 150 psi maximum pressure

- .070" cross-section Quad-Ring® Brand seal

- No side loading

Ring Size | Cross Section | DYNAMIC Recommended Gland Depth "C" |
STATIC Recommended Gland Depth "C |
AXIAL GROOVE Width "D" +.005/-.000 |

Q4004 - Q4050 | .070 ±.003 | .061 | .056 | .080 |

**Calculate the Seal Groove Diameter:**Groove Diameter

= Min Shaft Diameter + (2 X Dynamic Gland Depth)

= .371 + ( 2 X .061)

= .493 +.000 / -.002

(Recall the gland depth values in the chart are given as radial values)

**From the chart, the groove width is**.080 -.000/+.005

**Calculate the Minimum Gland Volume:**

Minimum Gland Volume

= ((Min Groove Dia - Max Rod Dia. / 2) X Min Groove Width

= ((.491 - .377 ) / 2) X .080

= .00456 in2

**Calculate the Maximum Quad-Ring® Brand Seal‚ Volume:**

Maximum Quad-Ring® Brand Seal Volume

= (Max Quad-Ring® Brand Cross-section)2 X .8215

= (.073)2 X .8215

= .0044 in2

**Compare the Minimum Gland Volume to the Maximum Quad-Ring® Brand 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)

Min Gland Depth = (Min Groove Dia. - Max Rod Dia.) / 2

= ( .491 - .377) / 2

= .057

Max Seal Squeeze = 1 - (.057 /.073)

= .219

= 21.9%

**b.**Min Seal Squeeze = 1 - (Max Gland Depth / Min Seal Cross-section)

Max Gland Depth = (Max Groove Dia. - Min Rod Dia.)

= (.493 - .371) / 2

= .061

Min Seal Squeeze = 1 - (.061/.067)

= .09

= 9.0%

Therefore, sufficient squeeze should exist to seal this application.

**Calculate the Maximum Clearance and evaluate possible extrusion problems**

Max Radial Clearance = (Max Bore Dia. - Min Rod Dia.) / 2

= (.388 - .371) / 2

= .0085

From the Clearance Chart, the recommended maximum radial clearance for a Quad-Ring® Brand seal with a hardness of 70 Shore A at 150 psi is slightly greater than .009 inches. The seal should work in this application.

**Select the Seal Size**

Refer to the Selection Guide and turn to the section which lists the seals having a .070 cross-section. This example's rod size of .374 is very close to the standard size of .375, so the standard seal for a .375 rod will probably work. Since in this application the sealing is occurring on the rod, use the Rod column to look up the seal size for a .375 rod. The correct seal is a number 4 -012 (with the 4 prefix signifying a Quad-Ring® Brand seal). Note the seal inside diameter, which is .364 ± .005. This will be used below.

**Calculate the Installed Seal Stretch**

Stretch % = ((Installed Seal ID - Original Seal Inside Diameter) / Original Seal Inside Diameter) x 100

= ((Rod Diameter - Original Seal Inside Diameter) / Original Seal Inside Diameter) x 100

= ((.374 - .364) / .364) x 100

= (.010 / .364) x 100 = 2.7 %