Flexspan Application

Senior Flexonics Pathway Solves Air Pollution Problem for Utility

A large southeastern utility had originally installed metal expansion joints at the boiler outlet to the air heater inlet location (sketch “A” below). This particular joint has a welded corner construction that repeatedly cracked after installation. Numerous attempts at repair have failed. This boiler is designed to operate under positive pressure. Any cracks in the expansion joint lets flash and flue gas escape into the atmosphere. The problem became so severe that the plant became non-compliant with the allowable EPA emissions levels.

Senior Flexonics Pathway determined that a good, long-term repair could be made by leaving the old metal joint in place and employing a new frame and fabric joint to provide a seal around the perimeter. The high temperature conditions (770 F) and the high corrosive atmosphere dictated the use of Corten frames and a multi-layer composite joint. Please see diagram below.

The joint was installed with the help of a Senior Flexonics Pathway craftsman to oversee the installation and do the fi nal splice. The joint has proven to be so cost effective and successful that Senior Flexonics Pathway has done many more similar repairs at virtually all the plants in this utility’s system.