Skeleton Oil Seal Radial Shaft Oil Seal with NBR FKM PTFE Material Options

The quality of a skeleton oil seal is primarily determined by two key
dimensions: appearance integrity and performance reliability. These directly
affect whether the seal can maintain long-term sealing effectiveness under
real operating conditions.

Appearance Standards

Rubber Section: The surface should be smooth, free from bubbles, cracks,
impurities, or missing material. Any defect may cause sealing lip failure.

Metal Frame (Skeleton): The rubber coating must be complete with no exposed
metal. The frame surface should be free of rust and burrs.

Spring: Must be intact without breakage, with uniform tension and no damage
to the groove.

Lip (Edge): Should be flat and sharp, without notches, warping, or dents,
ensuring tight contact with the shaft surface.

Dimensional Accuracy: The inner diameter must fit the shaft properly.
Excessive tightness causes heat and wear, while looseness leads to leakage.

Performance Standards

According to GB/T 9877.1-2008 (Radial Shaft Lip-Type Seals) and ISO 6194-
1:2007 international standards:

Oil Resistance: After immersion in transmission oil at 70 ± 5 °C for 24
hours, weight change should remain within −3% to +5%.

Gasoline/Benzene Resistance: Weight change should not exceed +20% after
immersion in the mixture.

Hot Air Aging (120 °C × 70h): Hardness change ≤ +10, tensile strength
reduction ≤ 15%, elongation reduction ≤ 40%.

Sealing Performance: No leakage should occur under specified pressure and
rotational speed.

Friction Performance: Low starting resistance, minimal frictional heating,
and long-term operation without burning the lip or oil spillage.

By applying these inspection criteria, the overall quality of a skeleton oil
seal can be effectively judged. A high-quality oil seal ensures longer
service life and more reliable sealing performance. Therefore, attention to
these details is essential during selection and procurement.

Minimum Order: 1000 pieces

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