Welding is a process that joins materials together by melting them. It can be used to join metals, plastics, and other materials. The welding quality depends on many factors, including the welder’s skill and equipment. There are many ways to check the quality of a weld, but here are some signs that indicate an excellent weld:
The weld has complete fusion between the base metal and the weld deposit.
- The weld has complete fusion between the base metal and the weld deposit.
- Weld is smooth, with no undercut or excessive reinforcement.*
- It’s free of porosity, cracks, discoloration (burn-through), spatter, and other surface defects.*
The weld is sound and durable. Weld strength has been verified by testing. The weld has met the mechanical properties specified in the welding process specification and follows AWS D1.1-2007, the standard for structural steel welding specifications.
The weld is smooth, with no undercut or excessive reinforcement.
- Undercut
- Excessive reinforcement
An undercut is terrible. It needs to be fixed in your weld, and it can make it harder for you to complete the next step of your project. Excessive reinforcement is also insufficient: if you put too much metal on your workpiece, there will need to be more room for other things like paint or polish (if that’s what you’re going for). The best way to avoid these problems is by practicing good technique and paying attention while working on an object so that you don’t accidentally use too much heat or move too quickly when welding.
The weld is free of porosity, cracks, discoloration (burn-through), spatter, and other surface defects.
- Porosity is a condition that occurs when the weld metal is porous or full of holes. This can be caused by gas in the weld, which pushes out of the molten metal as it cools.
- Cracks can occur during welding if there is insufficient heat to melt the base materials being joined together or if too much heat is applied. An attempt will be visible on both joint sides and may also be felt with your fingertip when you run it over the seam.
The weld bead width and contour are correct for the ordinary type, process, and material thickness.
If you are welding thin material such as sheet metal or light-gauge tubing, then a narrow weld bead is desirable because it will cool quickly and not have time to melt back into the base metal. On thicker materials like structural steel or cast iron pipes, however, it may be necessary to use wider beads so that they can fill out a larger area without leaving gaps that could cause stress concentrations in those areas.
The shape of the beveled joint edges is correct for the material thickness and welding process.
For example, if you are welding two 3/8″ thick mild steel plates together to make an H-beam or I-beam, then you need to make sure that your weld bead width and contour are correct for this joint type (butt joint), process (flux cored arc welding) and material thickness. See also 12 Best Portable ARC Welders – Top Rated, 9 Best Harbor Freight MIG Welders – Top Picks & Reviews
Look like a good weld.
When you look at a weld, there are several things to consider:
- The weld’s bead width and contour (shape) are correct for the ordinary type, process, and material thickness. For example, a fillet weld on a thin sheet metal part typically has a broader bead than one made with an arc-welding process on a thicker steel plate.
- The shape of the beveled edges formed by overlapping molten metal during welding is correct for your material thickness and welding process. For instance, if you’re using gas tungsten arc (GTAW) welding to join pieces of stainless steel together and your goal is to create smooth-looking joints without any undercutting or excessive reinforcement at all four sides of each seam–as opposed to just two sides–then ideally you should use wide-diameter filler rods that produce large amounts of melt pools with less penetration into base materials like aluminum or copper sheets because these materials tend not only to bend easily but also melt more quickly than heavier metals such as iron castings; this means less heat exposure time required per pass through them before stopping entirely so that no further damage occurs due too much heat buildup within their cellular structure over extended periods.”
Conclusion
We hope this article has helped you understand what a good weld looks like and how to recognize them. We also encourage you to check out our other articles on welding, including more tips on looking for these traits of good welds and other areas of your own business.
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Walton M. Edwards was born in 1994 in a coal mining town, he has worked as a welder, a hardware salesman, and as a pipe fitter and has been employed as a laborer for about fifty years. Walton is a native of Wabash County in Indiana, but he now resides in Bloomington, Indiana.