Oxy-Fuel Cutting Quiz

What is the ignition temperature of steel for flame cutting?

• 600°C

• 750°C

• 875°C

• 3100°C

What should you never do when using a cylinder valve?

• Open it 1.5 turns for acetylene

• Leave it open against the backstop

• Turn anti-clockwise to open

• Use hand wheels if fitted

What gas flame temperature is approximately 3100°C?

• Propane flame

• Natural gas flame

• Neutral oxy-acetylene flame

• Oxidising flame

What does a flashback arrestor do?

• Increases gas flow

• Measures flame temperature

• Prevents flame from travelling back to cylinder

• Stores excess fuel

Why should cylinders not be identified by colour alone?

• Colours are unique

• Paint can fade

• Labels are more accurate

• Cylinders don't need ID

What is the safest way to check for gas leaks?

• Use a match

• Shake the cylinder

• Apply leak test solution

• Smell the valve

What is snifting?

• Mixing gases

• Testing flashback

• Opening a valve briefly to clean it

• Pressurising hoses

What happens when cutting speed is too slow?

• Clean edge

• Sharp drag lines

• Melted and rounded top edge

• Undercut top

What gas has left-hand threads on cylinder valves?

• Non-flammable gases

• Compressed air

• Fuel gases

• Oxygen

Why are non-return valves used?

• To increase cutting speed

• To prevent backflow into the cylinder

• To maintain gas purity

• To mix gases