The role of the core.
The main function of the flashback preventer is to prevent the flame of the welding or cutting torch from backfiring (rebounding) along the gas hose from the mouth of the welding or cutting torch to the gas cylinder or gas source device, thereby avoiding explosion accidents. It plays a role in safety protection and is an essential product in the welding process.
You can imagine it as a “one-way fire damper” on a gas system.
If the normal flame is burning outside the nozzle of the welding or cutting torch during gas welding or cutting operations. But if for some reason (such as nozzle blockage, improper pressure, operational error, overheating of the torch, etc.), the combustion speed of the flame exceeds the speed at which the mixed gas is ejected from the nozzle, the flame will burn inward along the mixed gas pipeline. This phenomenon is called “tempering”.
If this flame is allowed to propagate in the opposite direction, it will burn through the hose all the way to the combustible gas cylinder (such as acetylene cylinder, propane cylinder)
The backfire preventer itself, gas pressure regulator, and even gas cylinder explosion may cause catastrophic consequences.
The tempering preventer blocks the propagation of flames through its internal mechanical structure, allowing only gas to flow from the gas source towards the welding torch and preventing gas from flowing in the opposite direction. This is the first line of defense, which can prevent gas backflow and to some extent suppress tempering. Fire blocking components are the most critical part. It is usually composed of multiple layers of fine metal filters or sintered metal sheets. When the flame enters the preventer, these small channels will divide the flame into countless tiny flames. Due to the excellent thermal conductivity of metals, they can quickly absorb and dissipate the heat of flames, causing the flame temperature to drop below the ignition point in a very short period of time, thereby extinguishing the flame.