In a D-type boiler, which tubes would be located in the generating tube bank?

In a D-type boiler, which tubes would be located in the generating tube bank?

• A. Waterwall tubes
• B. Furnace tubes
• C. Economizer tubes
• D. Superheat Support Tubes

Answer: (D)

In a D-type boiler, the generating tube bank is the section where water is heated by the flame and hot gases to produce steam, located inside the furnace area. The superheater is integrated into that same region, and its coils are supported by tubes known as superheat support tubes. These tubes reside in the generating tube bank to carry and position the superheater assembly within the hot-gas path, contributing to the heat-transfer process that converts water to steam and then further heats it. Waterwall tubes form the furnace walls, economizer tubes sit in the downstream economizer section, and furnace tubes are the radiant tubes in the furnace—none of these are the specifically recognized components that define the generating bank the way the superheat support tubes do.