01
The Challenge
The plant planned to replace a 5-inch section of IFB but found both cells needed it. With IFB unavailable, the alternative had to survive the upper terrace at about 980°C, radiate effectively to 190 tubes per cell, and last.
02
What Was Applied
Ceramic fiber modules installed in the upper terrace, with ST-17 sprayed onto the modules and no rigidizer.
03
Why It Worked
The coating raises the module emissivity to 0.85 to 0.95 and seals the fiber surface, so the modules both out-radiate IFB and resist the shrinkage that limits uncoated fiber. See Ceramic fiber testing.
04
Summary of Results
| Metric | Original IFB | Coated fiber modules |
|---|---|---|
| Heating of tubes | Uneven | Uniform, more intense radiation |
| Surface appearance | Baseline | Darker, evenly colored, cooler surface |
| Shrinkage or ablation after 8 months | None | |
| Service temperature and life of fiber | Increased |
Photographs showed the coated modules radiating more uniformly, with cooler coating temperature from increased radiation to the tubes, maintaining radiance uniformity and durability while reducing energy loss and maintenance frequency.