Welding and fabrication

Welding and fabrication are often used together in the context of mechanical engineering. No one ever takes a moment to consider that every part of their daily lives are impacted by these two skill sets.

Both welding and fabrication are essential in the creation of metal shapes and structures of all sizes - from humble nuts and bolts to majestic aeroplanes and even spacecraft. They require the use of different tools - fabrication for the preparing of raw materials and welding to assemble the individual elements for fabrication to complete the project. There are also very different skills required, although many welders can fabricate and often fabricators can weld.

Having said that, the complexity of welding often requires more specialised practitioners. Without intense practice, most welders wouldn’t be able to create the strong and neat welds essential to the fabrication process. When creating high-performance metal products, only welders with several years of extensive experience execute their tasks with the necessary degree of skill and precision.

This breakdown will explain the symbiotic relationship between these two distinct processes.

Welding

Welding is the process of joining pieces of metal with similar melting points together using heat. The most common technique is TIG welding but there are others such as gas metal arc, oxy-acetylene, laser beam welding and MIG. The material and its purpose determine which technique is chosen.

At its most basic, MIG and TIG welding create an electric arc between the welding rod or electrode and the work material. This produces an enormous amount of heat which melts the base metals and fuse them together.

Stainless steel generally has good weldability and can be welded using several different processes, including electron and laser beam, arc, friction, brazing and resistance welding. Unfortunately, it is one of the more difficult metals to weld. Because it’s not available in flux-cored form you have to use gas if you’re using a MIG welder or wire feed. Being able to weld stainless steel effectively is a sought-after skill in welding circles

However, there are some things you can do to make welding stainless steel easier. Probably the simplest and most effective trick is to thoroughly clean the steel before welding. This eliminates any chromium build-up, oil, dirt or paint. Using low heat, especially when the stainless steel is in thin sheets, is always advisable to prevent warping. Weld in short bursts of three to four seconds at a time, then stop and allow the steel to cool down before welding again.

Make sure you’re only using stainless steel rods if you’re using a stick welder. If you use regular MIG or flux-cored rods or wire the welded portions will rust. To further avoid this, a primer or clear paint can be applied over the welded parts.

Gas tungsten arc or TIG welding is the preferred process to weld stainless steel, but this is a more difficult method to master, compared to MIG welding. TIG welding allows for the manual control of the filler metal, which eliminates the spatter than can come from MIG. It is a slower process that results in an immaculate and visually appealing finished weld. In addition, TIG welding is better for the environment and for welders. Furthermore, this technique enables the welder to weld at low current and low heat - perfect for thin materials.

Fabrication

Fabrication is the over-arching plan for the end product. The process usually starts with a blueprint and runs through the layout, cutting, welding and assembling the individual parts.

Some of the processes that form part of fabrication include die-cutting, bending, stamping, hydroforming, grinding, drilling, spinning, stretching, rolling and finishing.

Fabrication essentially allows you to create a product out of metal using blueprint readings, layout, cutting and preparing materials for assembly. The most important technique in fabrication among the many to complete this process is welding. The fabricator sources the uncut raw materials such as aluminium and steel, which are then cut, bent and formed to the required specifications and size in preparation for welding.

Large fabrication shops provide added value to their customers by centralising the entire process, eliminating the need to find different suppliers for the various services. These companies usually handle the entire process starting with detailed drawings, moving through the fabrication process, and wrapping up with installation. The general scope of these projects includes structural frames for buildings, loose parts, stairs and handrails for buildings, and heavy equipment.

Despite welding being an essential part of the fabrication process, it’s only a single and clearly separate element.

The spark in fabricating

To ensure your welder is up for any fabrication task, whatever the size, application or industry, get in touch with Tru-Butt for welder repairs, rewinding and miscellaneous welding supplies.

For all your welding needs, including repairs, contact Tru-Butt today, for more information on their services.

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