How to determine if a polyurethane caster's bearings are waterproof?

To determine if a polyurethane caster's bearings are waterproof, consider the following:

Check the seal type: High-quality bearings typically use a double-lip seal, which effectively blocks water and dust intrusion and achieves an IP65 dust and water resistance rating. Low-quality products may have no seal or only a single-lip seal, resulting in poor waterproofing.

Inspect the bearing's appearance: Carefully inspect the bearing for visible gaps, cracks, or loose fit in the seal area. If there is a gap between the seal cap and the bearing body, or if the seal cap is deformed or damaged, the bearing's waterproofing may be inadequate.

Perform a waterproofing test: Submerge the bearing in water for 30 minutes, then remove it and inspect for any water seepage. If no water seepage is detected, the bearing's waterproofing is adequate; if water seepage is detected, it indicates a problem.

Reference product specifications and instructions: Check the caster's product specifications or consult the supplier to learn about the bearing's waterproofing performance and the sealing technology used. Some high-quality bearings will clearly indicate their water resistance rating or provide relevant water resistance test reports.

Understand the brand and manufacturer: Well-known brands and reputable manufacturers typically prioritize product quality and exercise stricter control over bearing seal design and manufacturing processes, making the water resistance and sealing capabilities of their bearings more reliable.