Custom made rubber bellows in pipe fitting

Rubber bellows in pipe fitting applications provide a folded connection whose geometry can be tailored to the mating ends. The flexible section should accommodate the movement it was designed for, rather than being forced to correct an undefined alignment problem between pipes.

Check the distance and relative direction of the pipe ends at assembly. Identify any intended axial movement or offset and verify that the available space allows the folds to deform without rubbing on neighboring structures. The end seats should match the actual pipe or fitting dimensions, including the length available for retention.

The material must suit the intended service medium and temperature. Pressure or vacuum requirements need to be specified for the complete connection; the presence of a bellows shape is not a pressure rating. ETOL can customize dimensions, hardness and compound around those defined conditions.

Distinguish the pipe supports from the flexible connection. The bellows should not be expected to carry an unsupported adjoining pipe unless that load is part of its approved design. Consider access to the end connections before installation, particularly if the surrounding pipework will later restrict inspection. Any change to the pipe arrangement should include a fresh check of the space and forces at the flexible section.

Fit the ends without twisting the body, and examine the connection as it moves through its intended range. Look for one side being pulled tight while the other is compressed excessively. During inspection, check retention as well as the wall between folds. A leaking or displaced end should be addressed at its mating interface instead of stretching the bellows farther to close a gap.

Material options

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

Hardness selection

Rubber: 30–90 Shore A. The flexible section should accommodate the movement it was designed for, rather than being forced to correct an undefined alignment problem between pipes.

Custom dimensions

The end seats should match the actual pipe or fitting dimensions, including the length available for retention.

Fit & assembly

Check the distance and relative direction of the pipe ends at assembly.

Use & inspection

Consider access to the end connections before installation, particularly if the surrounding pipework will later restrict inspection.

Photos illustrate structure or material only. Rubber bellows in pipe fitting applications provide a folded connection whose geometry can be tailored to the mating ends. ETOL directly manufactures custom-shaped silicone and rubber parts to your requirements.