As long as metal constructions are concerned, there’s really no possible way to avoid welding. Welding itself is a major part of building many devices and vehicles of modern time. Be it ships or automobiles; proper welding is needed to build almost any metal-based wonder of modern civilization.
However, there are various types of welding involved in the procedures that you might want to take up. And amongst all of them, knowing the difference in quality is a major factor that might lead to success or failure.
Not to worry, that’s what this article is all about. We’re about to discuss all there is to know about good weld Vs Bad weld. Just so you know, we’ll be talking about every specific detail. So, I’d advise you to read attentively. Let’s begin then, shall we?
- The Difference Between Good Welds and Bad Welds
- Ways to Inspect a Weld
- Bad Welding Vs Good Welding Depending on Weld Types
The Difference Between Good Welds and Bad Welds
The harsh truth is that not all welds are the same. It’s really not all that uncommon to come across a bad weld. Not only do they look bad, but they can also prove to be unsafe. To tell the difference between a good and a bad weld, you have to take a look at it. The factors to be noticed are:
- Are there any visible cracks in the weld?
- Can splatters be seen around the joinery?
- Does the seam appear to be messy?
- Notice the welding line. Is it thin?
However, you should know that different kinds of welds carry different levels of difficulty to achieve a good weld. If you see a seamless and apparently fit joint without any trace of the weld in sight, then that, my friend, is a good weld. And if you see the signs that I’ve mentioned above, the weld is bad.
Good Weld Characteristics
Before we get into further details, let’s talk about the characteristics to be found in a noticeably good weld. This will help you find out the difference between the quality of the weld.
If you see any characteristics in a good weld, it should be in the form of a bead without holes or cracks. And it should be uniform overall. It’s basic knowledge that a high-quality weld requires high-quality materials.
Apart from a good appearance, a high-quality weld also should have the needed strength to hold up various pieces of material fused together to serve their intended purpose within the overall structure. Thus, the weld at the joint should be as strong as the material it’s joined with.
Bad Weld Characteristics
Now that you know what a good weld should be like, let’s talk about the characteristics of a flawed or a bad weld. It will be messy in appearance. Plus, it will look unstable and feel flimsy. The joint in the weld will not be secure or strong. There are certain dangers that revolve around a bad weld.
Bad or poor-quality welds very often lead to faults and, in many cases, breakage in the concerned structure. There can even be uneven joints or jagged edges. These lead to instability or even destroyed materials and constructions. It’s also a danger to human beings and live animals in turn.
Ways to Inspect a Weld
Let’s discuss a few popular methods and procedures to inspect a weld.
The visual inspection method is the most common one among them all, and it doesn’t really cost you much. However, it requires quite a lot of knowledge and experience. This standard knowledge must be on the level of welder operators. Novice level inspection can lead to problems.
After a welding procedure is completed, an operator always checks for a few things. These include visual defects, lack of uniformity, various inconsistencies, undercut edges and uneven beads.
X-Ray or radiographic inspections are often used for more efficiency and accuracy. This process involves inducing gamma rays which pass through the metal surrounding the weld, including the metal of the weld. Deformities and defects can easily be detected by a trained inspector.
It’s easier to determine the strength of the weld with this method as well.
A brightly colored liquid dye is used in this particular kind of inspection method. This dye is sprayed over the weld and then is left to get soaked in the weld material. By the change of the liquid’s color on the surface, the inspector can identify the present irregularities and defects of the weld.
The dye should appear darker in the spot where the problem lies. It also shows the presence of an unwanted pinhole or cracks as well.
Magnetic Particle Inspection
For this process, special kinds of probes are used. These are placed on either side of the inspection area to allow amperage to pass within the material. When the amperage that passes through encounters any cracks or any kind of discontinuity, the probes are diverted.
Thus, amperage leaks through the surface and creates magnetic poles (Points of attraction). This allows the inspector to easily locate the irregularities.
Bad Welding Vs Good Welding Depending on Weld Types
Not all weld types are the same. And as I said at the beginning, each weld type has its own kind of difficulty. So, let’s look into the good Vs bad welds depending on the welding type.
Stick welding is probably one of the easiest types of welding you can learn. Plus, it’s pretty versatile. With stick welding, you can work with carbon steel, alloy steel, stainless steel, iron, nickel, aluminum and copper. Stick welding is also widely known as SMAW (Shielded metal arc welding).
It also has some other names that include flux shielded arc welding, and MMA (Manual metal arc welding).
It’s not that hard to determine whether a stick welding is good or bad. Let’s compare the qualities of a good stick weld and a bad stick weld below.
|Good Stick Weld||Bad Stick Weld|
|The good welds are generally straight and uniform.||Splatters will be seen.|
|You won’t see any splatter drops.||Bead inconsistency will be seen.|
|The thickness will be consistent.||Cracking, undercutting, and breaks in the bead will be visible.|
|The beads won’t have any breaks, holes or cracks.|
Just so you know, TIG means tungsten inert gas welding. This type of welding isn’t as easy as Stick welding. To be honest, it’s even harder than MIG welding and takes a considerably high skill level to pull off with perfection.
However, this type of welding can be applied to quite a lot of metal types. Even welding two types of metals can be worked with simultaneously. The workable metals include stainless steel, magnesium, aluminum, and copper alloys. With the right set of skills, TIG welds can look very clean.
Let’s look at the good and bad TIG weld qualities.
|Good TIG Weld||Bad TIG Weld|
|The tiny welds will be layered very neatly.||Wide and with no distinct pattern.|
|The weld will be patterned.||The beads will be erratic.|
|Visually quite appealing.||There will be signs of burnout.|
|Burnout or slags won’t be seen.|
This is perhaps the most common and easiest type of welding there is. This type of welding work is often applied in homes. MIG actually stands for Metal Inert Gas. In this procedure, the welding gun actually feeds a wire electrode which also acts as a filler material that’s used to join two metal pieces.
MIG welding is just great to apply on thin types of metals, including stainless steel, mild steel, and aluminum. A good MIG weld is easily distinguishable. And so is a bad one. Let’s take a look at the differences.
|Good MIG Weld||Bad MIG Weld|
|The weld will be straight and uniform in nature.||There will be cracks along the weld.|
|Smooth and patternless welds are expected.||The bead will be thin.|
|No instances of slag, holes, or cracking will be seen.||The weld will lack strength.|
|The bead will have no dips or craters.||Obvious lack of straightness and uniformity will be seen.|
This type of welding is rarely seen nowadays. However, let’s cover it because it is also considered a notable welding method. Oxy welding or gas welding is mainly used for metal cutting and maintenance. It’s also used in cases of welding delicate aluminum parts or brazing soft metals (Bronze and copper).
Finding out the actual difference between good and bad Oxy welds might seem a bit difficult. But let’s try.
|Good Oxy Weld||Bad Oxy Weld|
|The beads will be uniform.||There will be holes.|
|No sort of holes or globules of melted metal will be seen.||Lack of uniformity will be seen.|
|Insufficient penetration of work pieces will be seen.|
|Around the weld, large globs of melted metal will be visible.|
Well, it’s time to wrap this up. I believe we’ve gone through all the essentials regarding the good weld Vs bad weld topic. All types of welds can be done with perfection. However, after reading this article, you should be able to judge for yourself which one is good and which one is flawed.
So, hope you enjoyed the read. Farewell for now.