Custom molded square rubber seal/durable rubber O-ring

A square rubber seal should have corner geometry that corresponds to the joint it occupies. The section and local radius determine whether the rubber lies naturally in the seat or becomes distorted before closure. An O-ring style profile and a flat square gasket need different support, so define the required section alongside the outside shape.

Check the side lengths, closing gap, and contact width around openings. Select the compound for the medium, temperature, and repeated service conditions. The surrounding faces should close evenly without relying on the seal to correct a damaged corner or warped cover.

Fit without stretching one side to reach its seat. Inspect all corners as the joint closes and keep the rubber clear of passages. During maintenance, compare corner wear with the adjoining hardware. A local tear may require correction of the receiving radius or alignment before replacement rather than additional rubber thickness that changes compression along every side of the square.

Material options

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

Hardness selection

Rubber: 30–90 Shore A. Check the side lengths, closing gap, and contact width around openings.

Custom dimensions

An O-ring style profile and a flat square gasket need different support, so define the required section alongside the outside shape.

Fit & assembly

The section and local radius determine whether the rubber lies naturally in the seat or becomes distorted before closure.

Use & inspection

During maintenance, compare corner wear with the adjoining hardware.

Photos illustrate structure or material only. A square rubber seal should have corner geometry that corresponds to the joint it occupies. ETOL directly manufactures custom-shaped silicone and rubber parts to your requirements.