ICC Commercial Mechanical Practice Exam

What is a gas-tight joint obtained through metallic mixtures or alloys called?

1. Solder joint

2. Weld joint

3. Brazed joint

4. Fused joint

The correct answer is: Brazed joint

The concept of a gas-tight joint obtained through metallic mixtures or alloys best matches the characteristics of a brazed joint. Brazing involves joining metals through the use of a filler metal that has a melting point above 450°C but below the melting point of the base metals. This process not only creates a strong mechanical bond but also results in a joint that can effectively resist gases and fluids, making it suitable for applications where leakage must be prevented. In a brazed joint, the filler metal flows into the joint through capillary action, and upon cooling, it solidifies, forming a bond that is both durable and gas-tight. This is especially advantageous in scenarios involving piping systems and HVAC applications, where ensuring the integrity of joints is crucial to avoid leaks. Other joint types, while they may create strong connections, do not equally emphasize the characteristics of gas-tightness derived from metallic mixtures in the same manner as brazing does.