Arkansas Boiler Operator Practice Exam

Which material are the parts of a high-pressure boiler primarily made from?

1. Aluminum

2. Steel

3. Cast iron

4. Copper

The correct answer is: Steel

The parts of a high-pressure boiler are primarily made from steel due to its excellent strength-to-weight ratio, high tensile strength, and ability to withstand the temperatures and pressures typical in boiler applications. Steel is also highly resistant to the pressures associated with the steam produced in high-pressure systems, making it ideal for the structural components of boilers, such as the pressure vessel and piping. Steel can be treated and alloyed to enhance specific properties, such as corrosion resistance or thermal conductivity, further increasing its adaptability to different operating conditions. In contrast, while materials like aluminum, cast iron, and copper have their uses in other applications, they do not perform as effectively as steel under the demanding conditions found in high-pressure boilers. For instance, aluminum may not withstand high temperatures as well as steel, cast iron is more brittle, and copper is typically used in applications requiring good conductivity but does not have the necessary strength for high-pressure environments.