Standard MIG Welding Torch Design
Put simply, the welding torch is everything from the start of the hosepack up to the gas nozzle. A MIG welding torch, therefore, includes the connection between the torch and the union nut plus the shielding gas hosepack, as well as the various conduits, such as the protective hose, water inlet and outlet for water-cooled torches, power cable, gas hose, and inner liner.
Cross section of the welding torch and hosepack
The welding torch package also includes the handle with torch trigger and the torch neck with wearing parts such as the gas nozzle, contact tip, nozzle fitting and spatter guard. All together, a standard model measures up to six meters in length.
When purchasing a welding torch, it is important to look at the amperage. It makes no sense to use a 600 A welding torch with a power source that can only put out up to 220 A, nor to fit a high performance welding system with the smallest available torch. Your MIG/MAG welding torch should always be suitable for the maximum power range of your power source.
Gas-cooled or Water-cooled?
Another key question is whether to opt for gas or water-cooled. It’s a bit like buying a motorbike—should you go for the air-cooled single cylinder engine or the water-cooled four-cylinder one? The fact is water-cooled designs are often more durable and certainly boast better handling.
And welding systems are no different: Anyone who has used a welding system with water cooling right up to the tip of the gas nozzle will tell you how smooth the torch control felt and how easy it was to handle. Plus, water-cooled systems last longer and provide more power. Air-cooled welding torches are not suitable for higher amperages, whereas water-cooled torches continue to perform well at amperages up to 200 A higher.
TIG welding torches
TIG welding torches mean powerful technology for the very demanding and precise work involved in TIG welding. The wear parts system of these TIG torches is so extensive that each one can be ideally adapted to the needs of the welder and the accessibility to the component – with maximum process reliability. The very flexible, lightweight cable assemblies of the TIG torches can be easily handled and brought into other individual comfort positions. Ideal for the highest technical demands!
When speaking of welding equipment for tungsten inert gas welding (TIG), TIG welding torches are the subject. The small, powerful, flexible TIG torches stand for sophisticated technology for the very demanding and precise work involved in TIG welding.
Advantages of plasma welding: Often-overlooked PAW offers speed and affordability
Plasma Welding Torch sometimes offers greater welding speed than GTAW at lower cost than LBW, and it may be the most effective process for many applications. These include welding stainless steel expandable bellows, where PAW is more tolerant to joint misalignment than LBW and gives better penetration than GTAW; welding coated steels like those used in automotive exhaust systems; and welding in keyhole mode to make full-penetration welds in relatively thick material in a single pass.
While PAW is not as fast as LBW (depending on the application and laser source, LBW may be five times faster than PAW) or EBW, the capital equipment costs for PAW are typically a small fraction of the cost of the high-energy density equipment.
One disadvantage of PAW is its greater heat input, which produces wider welds and heat-affected zones than LBW and EBW. This may result in more distortion and loss of mechanical properties.
However, PAW offers an advantage over these processes in tolerance to joint gaps and misalignment. Although the arc is constricted, the plasma column has a significantly larger diameter than the beams. Adding filler metal also is accomplished more easily with PAW than with LBW or EBW.
What Are Electrode Holders and What is Their Purpose?
In welding, arc welding refers to the method in which metals are joined together using electricity that creates enough heat that melts the metal. ; An electric arc is created between the electrode and the base metal that melts the metal upon contact. Electrodes not only serve as the conductor of electricity to the base metal, but it can also become filler material of the weld. ;
A welding electrode holder is a device that is used to hold the electrode during the welding process. ; It is a clamping device that holds the electrode secure enough to enable you to weld in a variety of positions. ; They come in many different sizes and current capacity.
The welding electrode holder has an insulated handle that the welding cable passes through. ; Because it is insulated, there is no danger of short-circuiting should any part of it touch your work. ; The electrode holder allows you to quickly and easily change out your electrodes while using. There are insulated as well as non-insulated electrode holders. Insulated electrode holders should always be used to reduce the risk of shock.
How are electrode holders rated?
Electrode holders are made in different sizes and each manufacturer has its own designations for use. ; Holders are designed for a range of electrode diameters and also for a range of electrical currents. ; ;
You will need a higher amperage rating for a larger electrode holder. ; If the electrode holder is too small for the current being used, it will overheat and be damaged. ; Another thing to consider is the fact that the larger the electrode holder the easier your hands can become fatigued when welding. ; The larger electrode holders are also harder to manipulate when in differing welding positions.
Electrode holders should be inspected periodically to ensure that the spring and jaws are still strong. ; You should also evaluate your electrode holder to ensure that the insulation is in good condition. It is a pretty common thing to have to replace your electrode holder periodically. ; Replacing the electrode holder is a fairly simple thing to do. ; ;
Understanding MIG Welding Nozzles
The main function of your welding nozzle is to direct the shielding gas into the weld puddle in the most effective manner possible. The best welding nozzle choice will depend largely on your welding application, joint access, and process. Some welding nozzle designs offer better gas coverage; others offer better access. Some limit the efficiency of reamers in robotic applications. ;
The welding nozzle you choose should be heavily impact by your welding mode. Whether you weld in spray, pulse, or short circuit will heavily factor into the recommended nozzle design for your process.
Welding Nozzle Material
For the most part your MIG gun welding nozzles will be brass or copper in material. Brass welding nozzles have better spatter resistant properties in lower amperage applications than copper nozzles, but lose that advantage in higher amperage applications and can actually shatter when they fail. Copper welding nozzles have better overall spatter resistance and heat management at higher temperatures.
Nickel-plated welding nozzles (shown aside) have the advantage of increased durability and better spatter resistance than standard copper and brass nozzles. With nickel-plated welding nozzles you can always expect them to be plated to a copper nozzle, so you will benefit from all the good durability characteristics of copper with even great spatter resistance. The reason why nickel-plated welding nozzles last longer than regular copper is because the properties of nickel will deflect as opposed to absorb heat, meaning the inside and outside of your welding nozzle stay cooler while your MIG gun is operating. This allows for less spatter to stick to the nozzle, increasing it's life span. This is why plated welding nozzles are most common in robotic applications.
WHAT MIG GUN NECK IS RIGHT FOR YOU? ;
Black polymer armored MIG swan necks contain a thick copper wall with a conductor tube interior, so they don’t radiate or reflect heat as quickly. Optimizing MIG welding gun performance in specific applications can be a matter of choosing different components for the gun. Selecting the right MIG gun neck improves access to the weld joint, increases operator comfort and can reduce costs in the operation. ;
The biggest factor when choosing a gun neck is to ensure it provides proper access and visibility to the work. In some applications, the weld joint may be difficult to reach, or it may require you to reach down into a groove. A gun neck should provide optimal access to the weld joint — so you can do your best work while maintaining proper ergonomics. In addition to joint accessibility, several other factors play a role in the decision, including the welding process and parameters, the welder’s height and whether the gun has a curved or straight handle. ;