Correct option is A
A cutting blowpipe (oxy-fuel cutting torch) is used for cutting metals by directing a high-temperature flame onto the workpiece. The torch has two main functions:
1. Preheating the metal using a mixture of oxygen and acetylene.
2. Providing a high-pressure oxygen jet to oxidize and blow away the molten metal.
Role of the Central Hole:
· The nozzle of the cutting torch consists of multiple holes—outer holes for the preheating flame (a mix of oxygen and acetylene) and a central hole for the cutting oxygen jet.
· The central hole supplies pure oxygen at high pressure, which reacts with the heated metal, oxidizing it and facilitating the cutting process.
· This oxygen blows away the oxidized metal (iron oxide slag), allowing the cut to progress.
