Which component must be removed before a U-tube bundle can be removed?

• A. End cap
• B. Channel Head
• C. Tube sheet
• D. Flange head

Answer: (B)

The channel head must be removed first because it is the front-end housing that clamps and seals the ends of the U-tubes to the boiler. With the channel head in place, the tube ends are held and pressure-bound to the boiler shell, so the bundle cannot be withdrawn. Removing the channel head frees the tube ends and allows the U-tube bundle to be pulled out through the opening. The tube sheet stays fixed to the boiler shell and isn’t removed to extract the bundle, and the other components don’t prevent withdrawal on their own.