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AS568-314 O-Ring Size
300 series · 3/16" cross section · Heavy hydraulics, higher pressure
Inside diameter × cross section
18.41 × 5.33 mm
0.725″ × 0.21″ ·
outside diameter 29.08 mm (1.145″)
Dimensions
| Dimension | Inches | Millimetres |
|---|---|---|
| Inside diameter (ID) | 0.725″ | 18.41 mm |
| Cross section (CS) | 0.21″ | 5.33 mm |
| Outside diameter (OD) | 1.145″ | 29.08 mm |
Outside diameter is not measured, it is derived: OD = ID + 2 × CS.
If your measured OD disagrees with this, trust the ID and cross section — measuring
across the outside of a flexible ring is the least reliable of the three.
If you measured a used one
A ring pulled out of service will measure smaller than 18.41 mm, because compression set is permanent. If your measurement came in a little under this and the cross section roughly matches, -314 is very likely still the correct part. Ordering the size your worn ring measures is how the same failure repeats. More on this →
Nearby sizes in the 300 series
These share the same 3/16" cross section, so if the thickness is right but the diameter is off, your ring is probably one of these.
| Dash | ID (mm) | ID (in) | OD (mm) |
|---|---|---|---|
| -315 | 19.99 | 0.787″ | 30.66 |
| -313 | 16.81 | 0.662″ | 27.48 |
| -312 | 15.24 | 0.6″ | 25.91 |
| -316 | 21.59 | 0.85″ | 32.26 |