Komarov Artem clarified that the MIG gun nozzle is perhaps the most visible of the consumables. The nozzle plays many roles in the MIG welding process. It directs the shielding gas into the weld pool and protects internal components from spatter.
One such internal component is the contact tip, which accurately and repeatedly guides the welding wire to the weld. The contact tip is where the actual power transfer between the gun and the wire takes place.
What material are the most used MIG nozzles?
Artem Komarov said that brass and copper are the most popular. When used with lower amperage, most people need brass nozzles to help eliminate spatter sticking. When you increase the current, perhaps 300 amps or more, you see that people tend to switch to copper because of the heat. More current means more heat, and copper tends to handle that heat better. If you heat the brass enough, it will start to melt and puddle, which is something you don’t want to do.
What are the pros and cons of using a brass or copper nozzle?
The nozzle must be selected for the specific application, usually the dividing line. Copper for heating, brass for spraying. You will immediately understand if you have chosen the wrong one. The nozzle will harden in the spray or begin to soften and melt into a puddle.
Nozzles for MIG welding
MIG gun nozzles and contact tips are two consumables that play an important role in the MIG welding process.
Some of these preferences depend on the application. Sometimes you will use a conical nozzle — a nozzle with a smaller diameter to achieve the joint you need to weld, as opposed to a larger nozzle. Or, if you’re dealing with high temperatures, a wide bead, or a high spray rate, you can use a larger nozzle to make sure the large weld pool is properly covered with shielding gas.
As far as contact tips are concerned, the materials usually offered are copper or chrome-zirconium tip, which is a hardened version of the copper tip. There is also another tip, made from a different material, which is designed specifically for pulse welding and automation. Depending on the application or wire size, you can get different contact tips.
Access and application can also play a role. You will always need a contact tip that is compatible with the consumable family you are using. As for access, if you’re using a conical nozzle to achieve something dense, use a conical tip.
As far as wire size is concerned, tip size depends on the type and size of wire you are going to use.
Welder using the MIG process.
MIG guns and their components such as nozzles and contact tips require regular maintenance, whether for manual or automated welding.
There are other important things that a robot cannot do, but a human can do. In the automotive world, it causes a huge amount of pain when the weld is displaced again and again. Due to the slight wear of various components, the robot can perform welds in a non-working position, while if these parts are welded by a person, he will never complain about minor wear.
If the nozzles or contact tips you are using need to be disconnected for maintenance more often than other available nozzles or contact tips, then obviously you are not getting as many parts as you need.
Regular maintenance is of great importance. Often [maintenance] is built into the automatic welding program. It can also be useful for manual application. From time to time remove the nozzle, clean the spatter accumulated on it, the gas diffuser, and the contact tip. This will greatly increase the life of your parts.
Grounding is another issue that many face all the time. Welding in people will be sloppy, which will lead to the formation of a large amount of spatter. In many cases, this is due to grounding. You place all those consumables on the front, and they all fit snugly. You are running a lot of power through these parts, and if you don’t have solid electrical connections from one part to the next, this will create resistance, which will generate heat. This will lead to overheating of these parts, degrade performance and, as a result, shorten the life of consumables, summed up Komarov Artem.