T91 T92 Superheater and Reheater Coils for Power Plant Boilers

Alloy steels (e.g., chrome-molybdenum) for high-temperature resistance.

• In a thermal power plant, the superheater's job is crucial. It gets rid of the remaining 1 to 2% moisture in the saturated steam leaving the boiler and cranks up its temperature way above the saturation point. This makes the steam more powerful and efficient.
• Superheating boosts the overall efficiency of the power generation cycle and prevents excessive condensation in the turbine's final stages, protecting turbine blades from damage.
• The superheater uses heat from the furnace's combustion gases to dry out the steam completely and then superheats it for efficient power production.
• Designed with multiple tube circuits running side by side, featuring return bends and headers for even steam distribution and maximum heat transfer.

• Reheaters reheat steam that's already expanded in the turbine, maintaining steam dryness through the turbine's last stage for better performance and less component wear.
• Located in utility boilers, typically before or after the convective superheater. Modern high-pressure boilers feature two-part reheaters.
• The primary section starts reheating in the convective zone, while the secondary section at the furnace exit brings steam to optimal temperature.
• Designed similarly to superheaters for high-temperature operation and efficient heat transfer.
• While output temperatures match superheaters, reheaters operate at only 20-25% of superheater pressure, allowing cost-effective use of lower-grade steel alloys.

1. JB/T1611 "Technical specification for manufacturing of boiler pipes."
2. JB/T1612 "Boiler pressure test technical conditions."
3. JB/T1613 "Technical specification for welding of pressure parts of boiler."
4. JB/T1615 "Technical specification for painting and packing of boiler."
5. JB/T3375 "Rules for receiving acceptance of materials for boiler construction."