If the flame propagation is faster than the gas speed leaving a torch what will occur?

If the flame propagation is faster than the gas speed leaving a torch what will occur?

• A. Backfire
• B. Blowback
• C. Sooting
• D. Flameout

Answer: (A)

When the flame front moves faster than the gas leaving the torch, the flame can push upstream toward the torch tip. This upstream propagation is called backfire. It’s a flashback into the torch that can ignite gas in the lines if not controlled, making the system unsafe. Sooting comes from incomplete combustion, flameout is the flame going out, and blowback refers more to the flame reaching back into the gas supply lines; the scenario described specifically leads to backfire because the flame outruns the gas flow and travels back toward the torch.

When the flame front moves faster than the gas leaving the torch, the flame can push upstream toward the torch tip. This upstream propagation is called backfire. It’s a flashback into the torch that can ignite gas in the lines if not controlled, making the system unsafe. Sooting comes from incomplete combustion, flameout is the flame going out, and blowback refers more to the flame reaching back into the gas supply lines; the scenario described specifically leads to backfire because the flame outruns the gas flow and travels back toward the torch.