Fabric expansion joints consist of two major components– the fabric belt material and the metal frame. The frame can connect to the ducting by welding or bolting.
Each U.S. Bellows frame style has features designed to minimize the detrimental effects of temperature, movements, pressure, media, and turbulence. The U.S. Bellows team is experienced in evaluating application conditions and implementing designs that lead to long term expansion joint service.
Design alterations can include the following:
- Adequate stand off height
- Adequate face to face dimension
- Inclusion of liner
- Frame material
- Belt material
- Inclusion of accumulation barrier
- Inclusion of insulation pillow
- Proper bolt hole spacing
- And more
Although U.S. Bellows can provide weld-in and bolt-in frame styles, wherever possible, it is strongly recommended that the expansion joint be welded in place.
Weld in Designs
Weld in Design frame styles allow the expansion joint to weld directly to the duct or duct flanges. These frames styles are basic designs that can be augmented with optional components.
Benefits of weld in designs include:
- Weld in designs are less expensive to manufacture.
- Accurate field bolt hole dimensional data can be difficult to obtain and verify.
- Welded connections can accommodate "real world" field conditions and inaccuracies that occur during installation.
Bolt In Designs
Bolt In Design frame styles allow the expansion joint to bolt directly to duct flanges or equipment flanges supplied by others. These frame styles are basic designs that can be enhanced with the optional components.
Frame Design Components
- Accumulation Barrier For Applications with Particulate
- Insulation Pillow for High Temperature Applications
- Bolt-On Liner for Style 500
- Bolt-On Liner for Style 700
- Weld on Liner for Styles 100, 600
- Particulate Deflector