It’s easy to see the finished products we use every day for what they are — completed items ready for use. This could include everything from the pens we use to write our grocery lists to the vehicles we drive to the store. However, taking the time to consider how these items went from raw materials to usable items illustrates all the interesting methods used to create them.
One such method of fabrication is welding. There are many important industries that couldn’t function without the incorporation of welding.
But what is welding? Why is it so integral to these important industries? And how does it work?
Welding is a means of joining two objects. This can be done through the application of heat, pressure, or a combination of the two.
This is commonly performed with metals, although there are other materials that can occasionally be joined through welding. “Parent material” refers to the original pieces that are to be joined. “Filler” is what is used to join the parent material. Filler is also sometimes referred to as a “consumable.”
The material used for a filler is generally chosen to align with the parent material so the finished project looks cohesive. However, if the parent material is more brittle, a stronger filler could be used to strengthen the completed item.
There are a wide variety of joints that can be created through welding. There are five main overarching categories of these joints that depend on the positioning of the pieces that are to be joined. And within each category, there are multiple methods that depend on the shape of the joining pieces. For instance, different methods will need to be used if the pieces are flat where they meet, or beveled in some fashion.
- Butt Joint: This involves joining two pieces that are parallel to each other and flat. It is limited in joint thickness but simple and provides satisfactory strength.
- T-Joint: This is used when the two joining materials meet at a 90 degree angle, and when the intersecting materials meet in the middle of the adjoining piece.
- Lap Joint: This is used when the two joining pieces are layered on top of each other, commonly of different thicknesses.
- Corner Joint: Similar to the t-joint in that the pieces intersect at 90 degrees, except the pieces meet at the end to create an L-shape.
- Edge Joint: As the name suggests, this connects the edges of two work pieces. It’s often used with sheet metal to attach adjacent sheets.
The Process of Welding
There are multiple methods used within welding shops to join pieces of metal. They all share the basic approach of using heat and pressure to form joints, but the specific tactics will depend on the situation at hand. The most commonly-used methods are MIG, TIG, and Stick welding.
Metal Inert Gas (MIG) welding is an example of arc welding. It utilizes a welding gun, which has a spool of thread inside. A gas flows through the gun at the same time as the thread is fed into the weld pool, melting the thread and joining the work pieces.
Tungsten Inert Gas (TIG) welding is another form of arc welding. The welder holds a non-consumable tungsten electrode in one hand to create the heat, and a wire in the other. The materials are placed in the weld pool to melt the wire.
Stick welding is popular because it is fairly easy to learn. It makes use of a weld gun that has a metal rod running through the middle and surrounded by flux coating. An electrical current heats the rod to join the two pieces of metal.
Welding is used in many of the machines and structures that are integral to our daily lives. The examples of this are wide and varied, but we thought we’d point out some of the most commonly-used products that wouldn’t be the same without welding.
- Our city’s infrastructure depends on welding. Structures such as bridges are often held together through welded joints.
- Train tracks that bring in large shipments of goods to be dispersed to various retailers are welded together to withstand intense pressure and vibrations.
- The exterior and interior of our vehicles are essentially a patchwork of various metals. Many of these pieces are welded together.
- The aerospace industry relies on the stability of welded joints to assemble their structures.
- Even the attractions at your local theme park wouldn’t be the same without welding. The tracks used to keep the rides safe utilize strong, welded joints.
Welding shops make use of numerous methods and styles of welding to fit each particular job. Are you in need of expert welding services in the Nashville and Columbia, TN area? BMC Metalworks offers various forms of metal fabrication including welding services.