An automatic welding helmet is a headgear worn during welding. It plays the role of a protective shield against heat, infrared rays, ultraviolet light and debris. The automatic welding helmet as the name suggests gets darker automatically as it detects bright welding arc. This welding helmet provides protection even if the lens is not active.
Auto darkening welding helmets have filter lens or ADF which is a special LCD similar to the one used for designing digital numbers on a digital alarm clock. The filter cartridges in the lens are powered by lithium batteries. The lens also has light sensors which are there for detecting the welding arc. When the lens is not active, the filter is at shade 3 or 4 and view is similar to that of sunglasses. But as the arc is initiated, the sensors of the helmet detect the light and they become darker depending on the shade setting. This happens faster than the blink of an eye. Since the lens has UV and IR filter, your eyes will be protected from the harmful rays, whether the shade setting is active or not. The helmet goes back to its initial shade after the job is done. The helmet sets the welding joint while you are still wearing it. The helmet automatically adjusts to the shade depending on the welding application.
So as soon as the sensors in the helmet detect the arc, it darkens between shade 8 and 13. Your eyes are always protected and you don’t have to manually lift or lower the helmet whenever you need to inspect your work. The helmet has an auto darkening filter fitted that changes from light to dark as the welding arc is struck. Usually, the lens is a number 3 or 4 shade. As these sensors on the helmet detect changes in the light, the shade is changed. There are such advanced arc sensors too that can differentiate between natural light, bulb light and welding arc. Hence, they only reduce the shade when necessary.
Long story short, the lens on the helmet become dark the moment an arc is struck and then they become transparent when the welding is stopped. Before the welding starts, the welder wears the helmet in a safe down position and he can clearly see through the lens. As the arc strikes, in just 0.01 milliseconds, the lenses switch to a darker mode.
The helmet will protect you from burns, flashes and the bright light. Even though welding helmets were first used 50 years ago, they are still pretty common except for fact that they are now available with modern settings and technology. Auto darkening welding helmets are great not just because of the way they function, but how they have made the welder’s job easier and convenient than ever. They are available in a range of color, styles and even graphics. It is important that you choose one as per your comfort level.