Bellows are engineered and manufactured specifically for your application using a wide collection of materials. We are able optimize dimensional combinations to provide a solution to best meet your specification through multiple forming processes including:
Hydraulically
Roll Formed
Multi-ply
Extra Flexible
Extra Flexible Bellows
When it is desired to have a lower than normal spring rate in a bellows, or an "Extra Flexible Bellows", a combination of rolling and hydro forming can be used to make the ID of the bellows smaller than the diameter of the original tube from which the bellows is formed. This provides a greater depth of corrugation resulting in the lower spring rate. These bellows usually have a somewhat greater free length which permits a greater compression stroke however the spring rate increases rapidly if extended so they are not usually used in extension.
Multi-ply Bellows
These bellows are often used in applications demanding higher pressure ratings with minimum loss in flexibility. They are made by laminating two or more close-fitting tubes, then forming the convolutions as is done with single-ply bellows. Laminating two tubes of the same wall thickness T effectively increases the pressure factor to twice that of a single-ply bellows of wall thickness T and the spring rate is doubled, compared to a single-ply bellows of doubled wall thickness 2T whose spring rate is increased by a factor of 8. Two-, three- and four-ply bellows are offered in various materials for specialized applications.
Hydraulically Formed Bellows
A seamless or welded tube is placed inside a set of movable plates in a hydraulic corrugating machine. The bellows corrugations are formed when internal hydraulic pressure expands the tube outward between the plates. As the tube expands, it is folded longitudinally to produce a complete, convoluted bellows in one operation. Through tooling modifications, various shapes and diameters of the finished bellows ends can be formed as part of the corrugating operation. Bellows with an integral bottom can be formed by retaining the closed tube end as a part of the finished product. Hydro forming allows us to produce a high quality custom engineered bellows based on your application in sizes of .250" to 7.460" outer diameter in a variety of materials.
Roll Formed Bellows
In a roll-formed bellows, shallow convolutions are successively formed along the length of a thin-walled tube. These are deepened and narrowed through additional rolling operations until the final diameters and lengths are achieved. This fabrication process is most commonly used for larger diameter bellows. Although, some smaller multi-ply bellows require roll-forming due to the total tube thickness involved. We are able to produce bellows in sizes ranging from .750" to 12.000" outer diameter.
