Defects In Parts

A randomly spaced irregularly shaped surface indentation having a coarser texture than the normal o‑ring surface.

Excess rubber located at the parting line.

Fissures in the o‑ring surface which run along the circumference.

Cracks on the surface of an o‑ring.

Some parts mixed with a lot of other parts (size and/or material)

Mixture of parts in a different size and/or material (high %)

Fragment of sheet around an o‑ring (excess flash on the parting line)

Surface indentations irregular in shape with a rough surface texture caused by a buildup of deposits sticking to the mold cavity.

Distored part (Flatness and roundness)

Surface depressions are areas where the nature of the cured rubber surface is exactly the same as elsewhere on the o‑ring, but which is slightly depressed in localized areas.

Any extraneous matter (contamination, dirt, etc.) or depression formed by its removal.

A shallow recess on the parting line projection at inner and/or outer diameters with smooth edged blending into the part and have similar texture to the o‑ring surface, caused by deformity at the edge of the tool cavity.

A film like material, which extends from parting line projection on inner and/or outer diameters caused by mold separation or present due to inadequate trim.

Thick flash due to the molding process and stopping the trimming operation.

A shallow saucer like recess sometimes triangular in shape located on the parting line at the inner and/or outer diameters.

Depressions, usually irregular in form, caused by the removal of inclusions from the surface or the buildup of hardened deposits on the surface of the mold cavity.

Thread like recesses, usually curved of very slight depth in the inflexed state, with normal surface texture and rounded edge, caused by incomplete flow and knit of the material.

Also known as Buffing. A flattened and often roughened area around the inner and/or outer diameters of an o‑ring caused by excessive trimming.

Abrasion or coarse texture always on the surface of an o‑ring.

Incomplete flow and knit of the material.

Small part of rubber sticking on the o‑ring surface.

Miniscule pits, not localized, visible on the o‑ring surface.

A longitudinal imperfection in which the rubber adjacent to the parting line shrinks below the level of the molding. A longitudinal recess of wide angle U or W like cross sections, oriented circumferentially and located only at parting line. Present on OD and/or ID.

A pocked like bulge on the o‑ring surface resembling an air bubble. Blisters in a component resulting from the incomplete removal of air from the rubber during processing, the air remaining trapped in the o‑ring during the curing process.

Small line due to the incomplete flow and knit of the material.

Tapering of the o‑ring thickness located at the union. If you stretch the o‑ring, the defect will be more pronounced.

A continuous ridge of material situated at the parting line at inner and/or outer diameters, caused by worn or excessively rounded edges of the mold cavity.

The cross sectional radius in one ring half unequal to that the other half. It is caused by dimensional difference in mold halves.

Misaligned o‑ring halves caused by the lateral shift of one mold cavity plate relative to the other.

Wavy appearance on the parting line with normal surface texture.

It is a ripped out or peeled out irregular strip that is torn from the surface or parting line of one o‑ring.