New York Low Pressure Boiler COF Practice

Which type of boiler typically uses a roll and bead method for tube expansion?

1. Water tube boiler

2. Fire tube boiler

3. Combination boiler

4. Condensing boiler

The correct answer is: Fire tube boiler

The correct answer relates to fire tube boilers, which typically use the roll and bead method for tube expansion. This manufacturing technique is crucial in ensuring a secure and leak-proof connection between the boiler tubes and the tube sheets. In fire tube boilers, the hot gases produced from combustion pass through tubes that are surrounded by water. The roll and bead method effectively seals the tubes to the tube sheets, allowing for reliable operation under the pressure conditions typical of fire tube boilers. This method provides strength and durability to the connection, which is essential since fire tube boilers must withstand substantial thermal cycling and pressure changes during operation. The structural integrity provided by this expansion method contributes to the overall efficiency and safety of the boiler system. While water tube boilers and other types employ different techniques for joining tubes due to their unique designs and operating principles, the roll and bead method is particularly suited for the construction requirements of fire tube boilers.