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Metals have good ductility but poor resistance to abrasion - which means that abrasion prevention is required when metal pipes are used in high-temperature fluid catalyst service. On the other hand, ceramics possess great hardness and abrasion resistance, but they are brittle. Metal-Ceramic double pipe is a hybrid pipe using metal as an outer pipe and a ceramic material for inner pipe segments, applied together to utilize the two materials' advantages. Stress that may occur due to a thermal expansion gap between the metal and ceramic materials is eliminated by packing a special filler in between the two layers. The conditions under which FCC units are required to operate have become more and more severe and as a result, there exist increasing needs for abrasion-resistant piping materials suitable for handling high-temperature fluid catalysts. In response to these needs, heat-resistant metal-ceramic double pipe has been jointly developed by JGC and Taiheiyo Cement Corporation, and its manufacture and sale are now undertaken by Yakushima Denko Co. Ltd. |
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Features |
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- Good abrasion resistance at high-temperatures
- Applicable even for small diameter piping (dia.
 42 mm) where refractory lining is impracticable.
- Far higher reliability in small diameter applications than that of conventional mechanisms (such as cushion tee).
- Flanged connections
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Applications |
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- General-purpose piping (elbows, orifices) requiring abrasion resistance at high-temperatures.
(e.g., Catalyst withdrawal line at bottom of FCC unit regenerator)
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Experience |
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| Company |
Location Installed |
Size (inch) |
Materials |
| Outer Pipe |
Inner Pipe |
| A |
Elbow for Catalyst Withdrawal Line |
3 |
Carbon Steel |
Si3N4 |
| Carbon Steel |
Al2O3 |
| B |
Orifice for Catalyst Withdrawal Line |
3 |
Carbon Steel |
Al2O3 |
| C |
Elbow for Catalyst Withdrawal Line |
3 |
304H |
Si3N4
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| Tee for Catalyst Withdrawal Line |
4.5 |
304H |
Si3N4 |
| A |
Orifice for Catalyst Withdrawal Line |
2 |
304H |
Si3N4 |
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