Different Welding Methods in Practice
Friday, August 29, 2014 11:30:03 AM Australia/Sydney
The process of welding isn't quite as simple as applying a blow-torch to a piece of metal. It also goes far beyond having the proper equipment, with techniques to learn and different welding methods to consider.
That said, with a bit of practice and know-how of welding different metals, welding can be a viable activity for anyone with a steady hand.
Techniques are an important component of the welding process. While you're essentiallly just applying heat to two different pieces of metal until they join, with a rod in between, what you're looking for is a smooth join and a proper welding of the two metals. Words aren't quite enough to properly describe everything you need to know about welding, as it's a skill that needs plenty of practice to master.
For example, while you can slap two pieces of metal together and maybe complete a successful weld in a short time, what about welding different grades of stainless steel? The skill is more complex than physical motion. Different welding processes require specific temperatures and motions.
The difference between welding and brazing is important, as well as the difference between welding and soldering. The three can be broadly defined by temperature:
Welding generally uses the highest of temperatures. It requires a fine balance of melting two metals together, yet not allowing them to run. For welding, similar metals are almost always used to stop this from happening; for example, welding different types of steel, but not a combination like steel into aluminium. It is also usually the strongest form of metal bonding.
Soldering uses the least temperature of the three, and therefore produces the weakest join. It is used in more delicate materials that could potentially be damaged by the heat, but still need to be joined. Smaller, less heavy-duty jobs are soldered. These include objects with weak metal components, such as watches and copper pipes.
Brazing is very similar to soldering, but uses a higher temperature; the middle-ground between welding and soldering. It is perhaps the trickiest of the three, and can use metals that are difficult to heat and manipulate. There are different soldering and brazing methods, just as there are different welding methods. The next step is to identify the varying welders that do the job. While each of these use different forms of operation, they mostly differ in terms of welding different thickness metals.
Arc welding is a popular form of welding for many reasons, though motsly because the cost of the process is kept low. It involves creating an electrical current that is capable of heating metal the the point where they can be joined together. It creates a fairly strong bond, can be used almost anywhere and works on a wide variety of metals. However, arc welding is limited in the amount of jobs it can complete, and can be difficult for beginner to pick up due the complications of maintaining the 'arc'. Overall, this method is best suited to those undertaking small jobs or simply welding ethusiasts.
MIG Welding is another popular method that, instead of creating an electrical current, feeds a wire on a spool into the weld; this wire is then melted and becomes part of the joining process. MIG welding is easier than the arc method, and the strength of the weld makes it suitable for larger projects than simple jobs around the home. It is also useful for welding different grades of steel, or other metals such as aluminium.
TIG Welding is a slightly more complicated method, creating a weld area with a tungsten electrode. The process is longer and more difficult, but also has the most finesse of all the techniques. It also employs different welding gases that shield the area from contamination. For welding two different metals, you'd generally employ TIG welding.
Also of note is Flux-Cored Arc Welding, though the process is very similar to MIG welding. It still uses the wire-feed, but doesn't need gas. It's often used on outdoor projects, such as construction, due to its speed and portability. These different welding methods all have their uses and specific jobs, so pick the right one for your project.
Good to Know
Welding rods are of paramount importance in the welding process, though they are mostly used in arc welding. Before attempting to join two pieces of metal together, a od is placed over the top that will act as a sticking point. Once heat is applied, the metal from the rod melts into the process and provides the catalyst for the join. Of course, you don't want a large rod stuck on the join, so taking it off at the right time is important. This is a technique that will take some time to learn, but will come easily with practice. You'll also have welding rods for different materials, as the rod needs to match the metals being joined.
Every job or project is different, hence why there are so many different methods and pieces of equipment for welding different materials. The crucial thing to remember is that practice makes perfect; people spend years learning how to weld, so don't expect a perfect join in your first afternoon.