Home › AS568-448
AS568-448 O-Ring Size
400 series · 1/4" cross section · Industrial flanges and piping
Inside diameter × cross section
221.61 × 6.99 mm
8.725″ × 0.275″ ·
outside diameter 235.59 mm (9.275″)
Dimensions
| Dimension | Inches | Millimetres |
|---|---|---|
| Inside diameter (ID) | 8.725″ | 221.61 mm |
| Cross section (CS) | 0.275″ | 6.99 mm |
| Outside diameter (OD) | 9.275″ | 235.59 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 221.61 mm, because compression set is permanent. If your measurement came in a little under this and the cross section roughly matches, -448 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 400 series
These share the same 1/4" 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) |
|---|---|---|---|
| -447 | 215.26 | 8.475″ | 229.23 |
| -449 | 227.96 | 8.975″ | 241.94 |
| -446 | 208.91 | 8.225″ | 222.88 |
| -450 | 234.31 | 9.225″ | 248.28 |