Welding is a technologically complex and dangerous process. Neglect of UV protection methods and safety precautions can lead to injury and poor health. During the welding process, gases that can affect the work of internal organs are emitted. A welding arc has a significant effect on vision. The use of protective accessories helps prevent the harmful effects of substances emitted during welding.
What is a Welding Helmet?
Welding works are classified as particularly hazardous to health. Vision falls into the zone of increased risk of getting an industrial injury. Simple and auto-darkening welding helmets are used to protect vision. They serve as a barrier to optical UV radiation, molten metal particles, and thermal effects.
A classic or auto-darkening helmet is an individual means for protecting the eyes, respiratory tract, as well as the skin of the face and neck of the welder from concentrated broad-spectrum rays (ultraviolet, thermal, and infrared radiation), metal splashes, sparks, and harmful gases.
The skin is protected by a completely opaque and heat-resistant plastic part of the mask, and the eyes are protected by a built-in window with a light polarization filter that does not allow harmful radiation to affect vision. The whole accessory is fastened to the head of the welder using a forehead mount, the size of which is most often adjustable.
The Importance of Using a Welding Helmet
A simple or auto-darkening helmet is an obligatory accessory of a welder’s overalls; without it, the worker will simply not be allowed to work. If you do not use a simple or auto-darkening helmet when welding, this will certainly lead to injury to a welder:
- a flash burn of the skin of the face and neck under the influence of radiation from the arc, high temperatures, and splashes of molten metal;
- burns of the retina of the eye with ultraviolet and infrared rays, which leads to loss of vision;
- inflammation of the cornea of the eye (ophthalmia);
- direct inhalation of harmful fumes (such as aluminum oxide) and gases.
In no case should welders work with welding tools without a protective simple or auto-darkening helmet, even if the scope of work takes seconds.
Welding Helmet Construction
The design of simple and auto-darkening welding helmets differs. Yet, the main components are inherent in all products:
- A protective cover. It is usually made of heat-resistant plastic or pressed cardboard. There is a semi-circular cutout at the top so that the casing can be lifted up. The lower part of classic and auto-darkening helmets is elongated and covers the neck.
- An observation window is a thin glass layer. A glass welding lens with protection from UV/IR radiation is inserted into welding helmets for the possibility of visual control of the process.
- Light sensors and filters.
- Adjusting devices (polarization filters for sufficient darkening, delay controls, etc.).
- A light panel in models of the “chameleon” type. It recharges the batteries, receiving power from the light radiation of an electric arc.
- A fastener of the mask to the head with a lock.
Helmet bodies are made from several metallic layers to achieve the highest level of protection. The materials used are characterized by high heat resistance and electrical insulation. Some types of plastic, nylon, fiberboard, polypropylene, as well as fairly light alloys, such as Kevlar, have such properties.
Types of Welding Helmets
They distinguish between two types of welding protective accessories, namely goggles and masks/helmets.
Goggles
Glasses are considered one of the most primitive means to protect the welder’s organs of vision. They differ from auto-darkening welding helmets not only in the external design but also in the protection feature. If the mask protects an entire face, then, goggles are designed to protect solely the eyes. Three models are distinguished by design.
1. Open models are adjacent goggles with side protection, which can be both parts of the design and a separate element. The infrared light filter is made of mineral glass or polycarbonate. They can be used for auxiliary welding processes.
2. Closed products are close-fitting goggles fastened to the head with a headband. They encircle the supraorbital in such a way that ultraviolet light and radiation penetrate only through the filter and cover glass.
According to technical requirements, closed glasses have ventilation and an anti-fog function. There are models with a folding light filter, which allows users to assess the quality of the seam.
3. Chameleons. They can be attributed to an improved model of closed glasses. In this case, LCD screens are used. They can be automated or manual.
Welder glasses are used for low-intensity and auxiliary work. They are usually applied by experienced welders when performing work in non-standard conditions, for example, at height, when the use of a mask is impossible or inconvenient.
These models do not cover the face from the effects of thermal and mechanical effects. For additional safety, use creams with ultraviolet protection.
Welding Helmets and Masks
This is the most common type of protective equipment for welders. The main advantage of the accessory is that they have a greater degree of protection than goggles and completely cover the face, neck, and head of the welder from the adverse effects of welding.
According to the type of the used lens shade in protective windows, masks are divided into simple (with tinted glasses) and Chameleon models (auto-darkening welding helmets). Most helmets are equipped with polarization filters nowadays and allow coping with standard welding procedures.
To ensure simple and auto-darkening helmets safe fastening to the head, there are several types of design features.
1. With a handle. When working with a welding machine, it is required to hold the shield against the face.
2. With helmet attachment. More often, it is produced in the form of an adjacent screen.
3. With headband. Auto-darkening welding helmet fastening must be carried out both in terms of the girth of the head and in the parietal part. The adjustment step should be up to 10 mm. The tape width is at least 18 mm.
4. Universal. Such models have both a head mount and a handle in their design.
Smooth and uninterruptable darkening welding helmets work is achieved since there is no need to hold the mask in your hands.
Welding Shields
Some welders continue to use this type of protective accessory although it seems rather outdated nowadays. Welding shields are a flat base with built-in tinted glass at the top. A shield differs from the auto-darkening welding helmet since it does not protect the head as a whole but only its front part. Shields with tinted glass are common. No fastening is designed; welders should hold them with one hand during welding works. These are cheaper helmets.
How do Welding Helmets Work?
Now, let’s see how darkening welding helmets work. The principle of operation of passive welding helmets implies using light and heat-resistant materials in order to prevent the transmission of radiation, toxic substances, and hot particles. A protective window and cases are used for this purpose.
In standard models, the lens produced from glass or polycarbonate is used to guarantee secure darkening welding helmets work. Here, a thin glass substrate is used. Such models have unchangeable dimming. Thus, masks should be selected according to the type of work (MIT or TIG welding).
Recently, both experienced and beginning welders have preferred auto-darkening welding helmets of the “chameleon” type. Such models are equipped with automatic light polarizing filters. They not only provide the required protection of the face and neck from molten metal and the eyes from harmful ultraviolet and infrared radiation but also make the welding process as comfortable as possible. With the ability to adjust the main parameters, such a mask is suitable for most welding technologies. Thus, let’s see how it works more precisely.
The Principle of Operation of Chameleon Welding Helmets
The auto-darkening technology implies using an automatic light filter (ALF). Unlike ordinary tinted glass, the auto-darkening feature allows changing the degree of opacity depending on the light intensity, conditions, and welding mode. It is a fairly complex electron-optical device consisting of several metallic layers and a liquid crystal panel, each component of which performs a specific function:
- external protective glasses protect the remaining layers from mechanical damage;
- polarizing filters (films) protect against glare;
- a special UV/IR filter does not let harmful light affect the eyes;
- liquid crystal cells change the degree of dimming;
- photocells respond to changes in illumination (artificial or natural light).
The operation of the light polarizing filters is controlled by a miniature electronic unit powered by a built-in battery, which, in turn, is charged by solar power.
When there is no ultraviolet light, the filter has a minimum degree of darkening. In this case, the welder can see everything that happens through it and process metal without removing the mask from his head. However, while the welding arc is ignited, the lens darkens automatically.
Arc sensors deal with the detection of an electric arc and the transition of a signal to the electronic unit, which creates a voltage on the polarization filter (film). They act using liquid crystals. Lined up in a certain sequence, liquid crystal cells automatically adjust to the visible light creating the required dimming.
A bright flash triggers photocell-based arc sensors, located in the front of the filter, to transmit the signal for the power supply. Modern masks with auto-darkening welding lenses use several liquid crystal panels, which provide the necessary degree of dimming, regardless of the angle at which the light hits the filter. Due to light filters, such auto-darkening helmets are able to protect from optical radiation and bright light even in the off state.
As a result, the welder’s eyes are protected from light sensitivity all the time, without the need to remove or lift a solar-powered helmet up.
How to Select the Best Welding Helmet?
Welders are frequent clients of ophthalmologists not only because they neglected the main rule of work with passive welding helmets but also because they selected auto-darkening helmets with insufficient protection against the effects of ultra-violet rays.
Arc welding is considered the most dangerous type of electric welding since it is characterized by the most intense heat. Thus, the degree of light sensitivity and darkening of the auto-darkening helmets should be high. This is why it is crucial to select a suitable model for each type of welding work.
Here are some tips in this video, hopefully, they will help you figure out what to look for when choosing a helmet:
Preparatory Consideration
Before buying a passive welding helmet, you should decide on the following data:
- the intensity of application. This option helps decide whether you need a household or professional model;
- where the mask will be used (in a bright light premise or in a darkened room);
- the type of welding. For example, passive welding helmets designed for gas welding are not suitable for electric welding;
- the current used in electric welding. This parameter affects the dimming factor of light sensors.
- the probability of intense mechanical impact from the outside clarified the issue of an impact-resistant mask body.
Simple Mask or Goggles
For rare use, a simple passive welding helmet or goggles will do. When choosing standard solutions with non-regulated windows, pay attention to the following parameters:
- optical class;
- light diffusion;
- homogeneity;
- angular dependence;
- viewing area;
- fixed shade;
- protection against mechanical impact;
- wearing comfort;
- certification (will protect against forgery).
Signature is important:
- E – electric welding,
- G – gas welding,
- A – auxiliary work,
- C – marking for “Chameleon” light filters.
How to Select a Chameleon Mask?
If intensive work is planned, then it is better to look at the passive helmets with auto-darkening lenses. When choosing such kinds of solar-powered helmets, you should pay attention to a number of options.
Power sources
As a rule, there are two of them – lithium and solar batteries. When the battery is low, they give a light or sound signal. And in the event of a complete discharge of one of the sources, the second continues to feed light sensors, and it will not turn off during operation.
Function on/off
This option increases the service life of both the power supply and arc sensors, as well as ventilation. In the off-state, you can work in grinding mode.
The location of the adjustment block
It is desirable that it be on the front of the mask. This allows a professional welder to adjust the settings without interrupting work.
Filtration system
This tool is responsible for providing comfort and free breathing during work. If auto-darkening helmets work is carried out in rooms with a polluted atmosphere, a mask with a forced ventilation system is selected.
The number of sensors
This indicator directly affects the response speed. If we take the main characteristics, then the marking of the arc sensors should be 1/1/1/2 (optical class, uniformity, and light diffusion).
The adjustment of sensitivity controls, opening time, darkening, viewing angle, and grinding mode provide additional comfort during work and expand the scope of the mask with an auto-darkening lens.
Before the final choice, you should try on the mask, check the adjustment of the headband, and evaluate the size of the window to understand how auto-darkening helmets work. Pay attention to the marking of the light filter and the housing itself.
A welding helmet with an auto-darkening lens is a protective item for welding, which protects the welder from the negative consequences of the welding process. The mask protects not only the eyes, but also the neck, respiratory tract, and face. Refusal to use the mask with an auto-darkening welding lens can lead to a complete or partial loss of vision, as well as disruption of the work of internal organs.
Nowadays, auto-darkening welding helmets have gained a leading position in the welding equipment market. The Chameleon mask with automated dimming technology is distinguished by ease of use and provides maximum protection due to the use of several metallic layers.
FAQ
How do I know if my welding helmet is working?
To check whether darkening welding helmets work, welders use several tricks. The first method implies using a lighter with “silicon” which gives a spark in luminosity equal to welding arcs. We put on a mask on the head and ignite the lighter. The glass should darken.
Another interesting way to check is to use an IR radiation remote control from any household appliance. Their radiation is identified by automation as dangerous, and the glass is darkened.
What are the basic controls of a welding helmet?
All welding masks with auto-darkening filter lenses have additional modes and settings. Masks with a Chameleon light filter can have one, two, or even three modes of operation:
- Weld – welding (main) mode;
- Grind – operating mode with an angle grinder (active filter off mode);
- Сut – air-plasma cutting mode (with dimming 4-8 DIN).
The more modes are applied to the model, the more versatile the welding mask is.
What is the purpose of an auto-darkening welding helmet?
Auto-darkening welding helmets allow users to adjust the optimum level of dimming, achieving the safest working conditions. Helmets identify the required level of darkening automatically by analyzing an electric arc and form the needed dimming due to the use of a liquid crystal cell.
Do welding helmets have batteries?
Yes, if we talk about auto-darkening helmets, they are equipped with 2 batteries at once. Lithium and solar batteries are used. Most welding helmets where the dimming level is not regulated, work without batteries.
Can you change the battery in the auto-darkening welding helmet?
Yes, certainly. Auto-darkening welding helmets are equipped with 2 3-volt batteries of CR2032 type. They last for about 2 years, and then, need to be replaced with new ones.
How do I turn off the auto-darkening welding helmet?
Some auto-darkening helmets are equipped with the On/Off switcher. If there is no such button, then the helmet turns off automatically. If yes, users can turn it off forcedly.
