Flash Back and its Causes

Flash Back and its Causes Points : Flash Back and Causes While a flashback occur, the flame go out, and there is a loud squealing or hissing noise at the tip. This is typically accompanied by black smoke, issuing from the tip. But a flashback occurs, shut off the torch valves (oxygen first) and the cylinder valves. Have the equipment checked by the instructor before proceeding any further. In a flashback the flame is actually burning inside the torch. If this continues, the flame could work its way back to the cylinders or the pipeline and cause a violent explosion. Oxygen will bear the, flame. If is for this reason that the oxygen valves are shut off first. Every oxyacetylene equipment must have flashback arrestors installed if they are not install they might be purchased from the manufacturer. A few torches are construct with this. Causes of Flashback 1. By the offensive method to light the torch.
2. Moving the tip to the metal.
3. Obstacle in the tip.
4. Wrong oxygen and acetylene pressures. This is the majority common cause by beginners.