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Oakridge Bellows recently fabricated box fold style expansion joints which shipped to the John E. Amos plant in West Virginia.
Quarter sections for easier field installation These metal expansion joints, supplied through the Oakridge Bellows representive, Baker-Bohnert are duplicates of the original parts supplied with the OEM boiler that have been in successful operation for 30 years.
The box fold design, used throughout power plants for decades, is one of the most time proven expansion joints for boiler and air heater ducts.
The key to this design is the straight walls of the convolution profile along with the inner radius of the corner. In addition the 14 gauge thickness allows for weld repairs and field splices.
Inside radius increases bellows cycle life In addition to valuing the long service life of the original box-fold expansion joints, AEP ruled out other after-market replacement options that would have either reduced the inside air-flow or presented outside clearance problems.
Oakridge Bellows supplied the expansion joint in quarter sections with the splices in the middle of the straight rail sections. Typical box fold profile – straight walls improve flexibility
Box folds expansion joints are manufactured from carbon or corten steel.