Why Flare-Ups Happen and How to Stop Them Before They Start
Flare-ups are a common yet preventable safety concern when working with gas torches. Understanding why they happen and how to avoid them can make all the difference between a safe, steady flame and a sudden burst of fire.
What Is a Flare-Up?
When working with gas torches, one of the most important safety aspects to understand is the phenomenon known as a flare-up. This occurs when liquid gas passes through the jet orifice of a lit burner, producing a large uncontrolled flame that can quickly become a fire hazard. Knowing why this happens and how to prevent it ensures not only better safety but also optimal performance and longer equipment lifespan.
Flare-ups typically happen when a blowtorch is used at extreme angles or upside down while connected to a gas cartridge not designed for that purpose. In this position, liquid gas from the cartridge can flow directly into the burner without being properly vaporized. When the liquid reaches the lower pressure of the burner outlet, it rapidly turns into gas, creating a flame much larger and hotter than the torch is built to handle. The result is a sudden burst of flame instead of a steady, controlled flame, which can be dangerous for both the user and the surroundings.
Why Tilted Torches Trigger Dangerous Flare-Ups
This effect is most common with handheld torches where the gas cartridge is attached directly to the blowtorch. Inside the cartridge / cylinder, the gas is stored under high pressure in liquid form. If the torch is flipped upside down or held at a steep angle, the liquid gas travels through the system without fully evaporating. Once it ignites, it produces excessively large and uncontrollable flames. The regulator, designed to handle vaporized gas, may also freeze or lose efficiency if cooled by the compressed liquid, reducing its ability to stabilize the gas flow and increasing the likelihood of flare-ups over time.
How Modern Sievert Torches Minimize Flare-Ups and Ensure Safe Operation
Fortunately, modern Sievert torches are engineered to reduce such risks. Models like the Powerjet and Turbojet should be used with high-quality gas cartridges such as Ultragas, Propane, or MAPP gas. These gas cartridges / cylinders are designed to maintain safe and efficient combustion with no flare-ups. For lighter tasks, the Handyjet features a built-in pre-heating system that allows it to perform reliably without requiring a special gas cartridge / cylinder.
To minimize flare-up risks, always let your torch run upright for about 20–30 seconds after ignition. This gives the internal components time to heat up properly and the gas to vaporize.
Flare-ups can also occur after storage, particularly in cold weather. Propane trapped in the hose may condense into liquid form, leading to instability the next time you ignite the system. To prevent this, always release residual gas safely after each use. When shutting down your torch system, follow these steps:
- Ensure the burner is pointed away from people, objects, and heat sources.
- Turn off the gas flow on both the handle and the cylinder.
- Once both are closed, gently open the handle valve to let any remaining propane in the hose escape before storage.
The Key to Safer Torch Work
By following these simple but critical steps, you maintain control of your flame, protect your equipment from damage, and ensure safe operation in any working conditions. Understanding flare-ups and how to avoid them should be part of every professional’s basic knowledge when working with gas torches.