High quality rubber silicone O-ring/round washer for seal

A round washer for seal applications occupies a circular interface between mating parts. The custom rubber component can be sized for the central opening and surrounding sealing area. When choosing between a flat washer form and an O-ring form, the cross section is as important as the overall diameter.

A flat section needs suitable faces to support its width, while a round section usually works within a joint designed around its compression. Similar outside diameters do not make these profiles interchangeable. Check the groove or seating area, the available space, and the way the mating parts close before settling the shape.

The rubber compound should suit the substance and temperature at the joint. During assembly, keep the ring flat or correctly seated in its groove, avoiding twist and contamination. Look for pinching as the parts come together. The finished seal depends on the condition and alignment of the mating surfaces, so inspect those areas whenever a replacement ring is fitted rather than assuming the rubber is the only part affecting the joint.

Material options

Silicone. Custom formulation and color for the intended contact conditions.

Hardness selection

Silicone: 20–80 Shore A. A flat section needs suitable faces to support its width, while a round section usually works within a joint designed around its compression.

Custom dimensions

When choosing between a flat washer form and an O-ring form, the cross section is as important as the overall diameter.

Fit & assembly

Check the groove or seating area, the available space, and the way the mating parts close before settling the shape.

Use & inspection

During assembly, keep the ring flat or correctly seated in its groove, avoiding twist and contamination.

Photos illustrate structure or material only. A flat section needs suitable faces to support its width, while a round section usually works within a joint designed around its compression. ETOL directly manufactures custom-shaped silicone and rubber parts to your requirements.