Bellows and Covers Glossary

Bellows boots

Round bellows used to cover screws, rods, pistons or other round elements.

Collar

An extended element on bellows ends that are used to attach bellows and covers to a structure. Hose clamps are used to hold collars in place.

Collar-flange

A more complex end condition for bellows and covers. It consists of a collar with a flange attached. Users may attach the end condition via the collar of the flange portion of the end condition.

Convolutions

Each segment of a sewn bellows profile consisting of two panels stitched together. Bellows  and way covers are constructed of multiple convolutions assembled to meet  the required extended length.

Curtain bellows

Curtain covers are flat bellows and may incorporate stiffeners to help hold their original shape and allows them to be mounted vertically or horizontally. Typical applications are to screen an area to prevent accumulation of debris in a recess or to provide protection in a single plane.

Flange

A flat surface end condition on bellows and covers. This end is clamped or bolted to the supporting structure.

Flange holes

One or both flange ends can be provided with a hole pattern to accommodate mounting. Customers must specify the hole pattern. This option can be used with our without the steel back-up flange.

Hose clamps

Hose clamps are used to attach round bellows to the customer’s structure. They are provided standard with each round bellows.

Platform skirt

These bellows are typically mounted vertically. They are constructed from polyester

Sewn tabs

Sewn tabs are an added feature used to stabilize long vertical bellows and covers. These tabs, added to alternate convolutions, prevent undue stress on seams and sagging at the top of the bellows or cover. The need for sewn tabs is dependent on both the length and size of the bellows or covers. Contact Joyce/Dayton with questions about your specific application.

Stiffener guides

These are internal stiffener guides are used to support non-vertical bellows and to prevent the internal diameter for contacting the shaft or screw they are protecting.  Non-circular stiffener guides are sometimes used to support long horizontal way covers. These guides are fitted between the sewn convolutions of square or rectangular way covers.

Steel back-up flanges

These flanges are used to provide stiffness when mounting the flange ends on way covers and bellows. Customers may specify a mounting hole pattern for back-up flanges by providing a drawing at the time of order.

Velcro tabs

Flange mounted bellows and covers are sometimes attached to machinery with Velcro tabs or strips. This method of attachment does not require drilled holes.

Vents

Vents are generally used when the bellows must open and close at a fast rate of speed. Vent holes placed in one or more convolution allow the bellows to collapse more quickly in fast cycling applications.

Way covers

C-Shaped or U-Shaped bellows used to cover machine ways or other linear devices. These are typically mounted in non-vertical applications.

Zippered bellows

Zippers allow bellows installation and removal without the need to detach the part being covered. Typically, zippers are installed in a spiral to minimize the increase in the length of the bellows.