Reverse Flow of Gas: Flashback Safety

to potentially hazardous conditions our reverse flow of gas and flashback a reverse flow condition occurs when fuel gas enters the oxygen stream or when oxygen enters the fuel gas stream reverse flow most commonly occurs when one cylinder goes empty during operation creating an imbalance of pressure in the system it can also be caused by a clogged or blocked tip if reverse flow isn't stopped gas can flow all the way back into the cylinders if these gases are ignited within the system it can cause equipment damage and personal injury reverse flow can be prevented by using clean tips making sure that the flow of gases from the tip is not blocked using recommended pressures and installing reverse flow check valves the reverse flow check valve is a safety device designed to allow gas to flow in only one direction from the regulator to the torch since reverse flow check valves are mechanical devices they should be routinely tested according to the manufacturer's recommendations to ensure they remain in proper working order I want to emphasize that if ignition of mixed gases in the system does occur a reverse flow check valve alone will not stop a flame from proceeding upstream flashback is a term used to describe the condition resulting from mixed gases burning inside the torch one common cause of flashback is not supplying an adequate volume of fuel gas to support the demand of the tip this condition is called starvation when this occurs the flame flashes back to the mixer a flashback if not extinguished immediately will likely result in damage to the torch and other components of the system and could cause serious injury to anyone near the operation flashback arrestors are devices which have a sintered stainless steel filter that extinguishes the flame and prevents it from moving upstream in the system flashback arrestors may be installed between the regulator in the hose however since the hose itself contains a significant amount of gas a torch mounted flashback arrestor has been developed to prevent a flashback from entering the hose some Victor torches and torch handles like this one incorporate built-in flashback arrestors and reverse flow check valves with this device protection against these hazards is always in place and accessory check valves and flash or esters are not necessary remember reverse flow check valves by themselves will not prevent a flashback so it's a good idea to always use both check valves and flashback arrestors in your system

Channel: Norco Marketing

Views: 113,159

Keywords: Reverse Flow, Gas, Flashback Safety, victor, oxy-fuel, fuel gas, torch, norco

Id: dVZ1LbQCU3o

Length: 3min 42sec (222 seconds)

Published: Mon Jan 25 2010