Millwright Level 1 Practice Exam

What is the primary role of the secondary gas in plasma arc cutting?

1. Ignite the arc

2. Cools the torch

3. Enhance conductivity

4. Stabilize the arc

The correct answer is: Cools the torch

The primary role of the secondary gas in plasma arc cutting is to stabilize the arc. Secondary gas helps maintain consistent energy delivery to the workpiece, which is crucial for achieving precise cutting. It serves to enhance the performance of the plasma by controlling the shape and temperature of the arc. This stability is vital as it ensures the cutting process is smooth and effective, contributing to the overall quality of the cut. Igniting the arc is typically achieved through the initial arc created by the primary gas. While cooling the torch is important, it is not the primary role of the secondary gas. Enhancing conductivity and stabilizing the arc are related functions, but stabilization is the more critical aspect in the context of the cutting process.