Groove Design Guidelines
Static Sealing
Groove Width:
W = 1.05 × CS + 0.005"
Groove Depth:
D = 0.75 × CS
Compression:
15-25%
Surface Finish:
32 RMS max
Dynamic Sealing
Groove Width:
W = 1.10 × CS + 0.010"
Groove Depth:
D = 0.75 × CS
Compression:
12-18%
Surface Finish:
16 RMS max
Engineering Note: These guidelines apply to standard O-ring installations. For critical applications, consult with our engineering team for application-specific recommendations.
Installation Best Practices
1
Preparation
Clean all surfaces thoroughly. Remove debris, old sealant, and inspect for damage or wear.
2
Lubrication
Apply compatible lubricant to O-ring and groove. Use silicone grease for general applications.
3
Positioning
Install O-ring in groove using proper tools. Avoid stretching or twisting during installation.
4
Verification
Verify proper seating and compression. Check for pinching or rolling before final assembly.
Critical Installation Tips:
- Never use sharp tools that could damage the O-ring
- Check compatibility between O-ring material and lubricant
- Avoid overstretching - maximum 50% stretch during installation
- Inspect lead-in chamfers - 15° minimum angle recommended
Material Selection Guide
Temperature Considerations
-40°F to +248°F (-40°C to +120°C)
NBR
-67°F to +302°F (-55°C to +150°C)
EPDM
-40°F to +302°F (-40°C to +150°C)
HNBR
-4°F to +428°F (-20°C to +220°C)
FKM
-67°F to +482°F (-55°C to +250°C)
Silicone
Application Environment
Petroleum Products
NBR, FKM, HNBR
Water & Steam
EPDM, Silicone
Chemicals & Acids
FKM, FFKM
Food Contact
Silicone, EPDM
Design Calculations
Compression Calculation
Compression % = ((CS - Groove Depth) / CS) × 100
Example: For 0.139" CS with 0.103" groove depth
Compression = ((0.139 - 0.103) / 0.139) × 100 = 25.9%
Compression = ((0.139 - 0.103) / 0.139) × 100 = 25.9%
Stretch Calculation
Stretch % = ((Groove ID - O-Ring ID) / O-Ring ID) × 100
Note: Maximum recommended stretch is 50% for installation, 5% for service
Volume Swell
Volume Increase = (Final Volume - Initial Volume) / Initial Volume × 100
Acceptable Swell: NBR in oil: 10-30%, FKM in fuel: <5%
Industry Standards
AS568
Aerospace Size Standard
DimensionalASTM D2000
Rubber Classification
MaterialISO 3601
International Standard
GlobalAMS-R-83485
Aerospace Material
MilitaryNeed Engineering Support?
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