Are you fascinated by welding but unable to wrap your head around the various types of welds? You're not alone! Sometimes it is tricky to know how every weld type works and what purpose they serve.
This article gives you a perfect idea of the different types of welding and their applications during the metal fabrication process.
The Different Types Of Welds-
The most common weld type is the "fillet weld," named after its cross-section view's shape. Other types include plug welds, flange welds, backing welds, seam welds, and surfacing welds, which will be discussed later in this article.
This article aims two-fold; first, to help you discover the various weld types and types of welding, and second, to allow you to learn about their real-life applications.
Fillet Weld
As one who is new to welding, the fillet weld will likely be your first weld joint to learn as it is accepted to be the most commonly used weld. What is a fillet weld? It is a solid connection between a vertically-positioned plate and a horizontally-positioned plate.
Both pieces involved in a fillet weld are usually perpendicular (as in an L or T joint). You can have them joined together as overlapping pieces. An essential reason why fillet welds are typical is how cost-efficient they are.
In addition to being affordable, fillet welds are considered more economical than groove welds (which we will discuss as we go on).
They are helpful in construction that requires significant welds, as in steel construction. Anything other than a fillet weld in this situation is not economical.
Another plus for fillet welds is their ability to hold a considerably heavy load. What is quite unfortunate, however, is that professionals—at least in the welding community—do not deem fillet welds fit for practical use in projects where loading is dynamic to the welding site.
The different types of welding include:
Full fillet weld
In the full fillet weld, the diameter of the weld is the same as that of the joined metal.
Staggered intermittent fillet weld
This type refers to two intermittent weld lines on a joint. A perfect example is from a tee joint, where the increments of the fillet are staggered in one line when compared to the other.
Chain Intermittent fillet weld
This type of fillet weld refers to two lines of staggered fillet weld in a T or lap joint. In this fillet weld type, the welds on both lines are opposite.
Another term for intermittent welds would be stitch welds.
Groove Weld
Groove welds are a weld of a joint in a groove.
A good example that adequately captures the groove weld is the joining of two beveled workpieces.
The beauty of groove welds is that they allow the joining of parts of a workpiece in the same plane by simply depositing welding beads between them into the groove.
Compared with other types, the groove weld takes more time. It requires the beveling of the two pieces with a bevel machine or grinder. The weld is the same, but job preparation takes longer.
However, the groove weld creates a stronger weld better for complete penetration. Groove weld applies to the following:
Pipework or pipefitting
Hollow structural steel connections like handrails
Column splices
Surfacing Weld
The surfacing welding process is welding to the surface of the workpiece rather than in a joint. This welding technique can achieve specific dimensions, replace, build up, or repair worn metal surfaces.
Surfacing welds contribute the wear-resistance layers of metal to the surface of an object, strengthening it.
This welding technique is a cost-effective means of prolonging and protecting the shelf life of tools and equipment used for aggressive work or in an application that has increased wear potential. You can enhance the final weld quality using a surfacing weld with square butt joints.
Listed below are common types of welding that you will likely come across:
Furnace fusing
Gas metal arc welding surfacing
Plasma arc surfacing
Oxy-acetylene surfacing welding
Submerged metal arc welding surfacing
Submerged arc welding surfacing
Gas tungsten arc welding surfacing
Plug Weld
Plug or rosette welds are circular welds made through a hole in one of the members in the joint. The entire scope of plug welding is to fasten two different surfaces together, utilizing a little hole in one of the pieces.
The weld is applied to the inside of the hole, joining the two together.
Plug welds are commonly applied in the automotive industry instead of spot welds when there isn't sufficient space to take the equipment for spot welding. The resulting weld's quality is usually more robust than a spot weld.
Plug Welding Uses:
You can also use this welding type to repair holes in aerospace components that are pretty expensive, restoring them to a brand-new state. Plug welds help cut costs and are applicable in the following:
- Used in welding rod or bung ends in a pipe or tube
- Plug welds can join metals of varying thickness
- Useful in manufacturing and repair of automotive components such as floor pans
Slot Weld
The slot weld is a type of weld made in a hole in one member, joining it to the surface of the other member. The cavity exposes the second member. The elongated hole may be open at one end or entirely or partially filled with weld filler.
The significant difference between a slot and a plug weld is that the shape of the plug weld is determined only by its diameter. The shape of the slot weld is characterized not only by the diameter but also by the length.
Slot welds come in handy when a rewired overlap between two surfaces occurs. Below are unique applications of spot welds:
- Used in the transmission of shear force in lap joints
- It helps to prevent the buckling of overlapped parts
Flash Weld
Flash welding is a known method to eliminate the need for filler metals. When creating flash welds, a current passes to form a resistance between two distinct surfaces.
When the surfaces are brought together at a point, the applied current flows through them and melts the material. The melted material is what you see as a distinctive flashing when they exit the joint in a spray of particles. Among the molten materials are contaminants and oxides.
When there's enough melted material eliminated, an applied force joins the surface of both metals. This process is what facilitates a butt weld that is devoid of residual melted metal in the joint.
The process of flash welding is economical, fast, and able to join metals that are not similar at different melting points.
Flash welds uses are:
- Joining workpieces that are thick, such as pipes and chains
- Connecting sections of mainline rail
- Fussing metal sheets, bars, and rods
Seam Weld
Seam welds are a type of weld that allows workpieces to be welded along a progressive seam and overlapped. People create this unique type of weld through two different methods:
Resistance Seam Welding
Resistance seam welding involves the process of spot welding but with motor-powered wheels rather than a fixed rod for the welding electrodes.
This type of seam welding is popular in the fabrication of metal sheets and manufacturing components of automobiles such as radiators, steel drums, and fuel tanks.
Friction seam welding
In the friction seam welding process, heat occurs through friction in place of stationary electrodes. This welding type helps to get rid of any occurrence of interdiffusion.
The friction seam welding method is perfect for materials that are naturally hard to weld using conventional methods.
Below are a few benefits of seam welds:
- They provide durable and sturdy welds
- Seam welds are pretty easy to perform
- They are suitable for the manufacture of gas and liquid-tight vessels.
Spot Weld
Spot welds use a technique called "spot welding." In this technique, welding occurs between two workpieces as spots. You can think of this as a form of resistance welding that is adopted to bring together at least two metal sheets without filler material.
The ideal way of making spot welds is by focusing electric current on small spots between adjoined metal sheet surfaces—shaped electrodes made of copper help to pass the electric current needed to join the two metal sheets.
The applied current starts to melt the metal. Once melted, the current is removed, and steady pressure is maintained as the molten metal material starts to harden, producing a spot weld.
Like the earlier reviewed weld types, the spot weld is inexpensive and easy to create. They are also a popular choice of weld in industries like:
- Aerospace
- Automotive
- Electronic
- Firearms manufacturing
- Building of metal furniture
Upset Weld
Upset welds are consequences of resistance welding processes that produce fusion across an adjoined surface area. Upset welding can be done concurrently along a joint by combining pressure and heat.
Pressure is first applied before and during the welding process to create heat. The heat produced during upset welding comes from the resistance to the free flow of electric current at the contact points between both surfaces.
You'll find upset welds used in wire ring fabrication, construction of wheel rims, burner rings, and every other circular part of a machine that has a small cross-sectional area.
Using upset welding affords you some distinct benefits, like:
- High-quality welds with fewer fusion defects
- It is compatible with various workpieces that are pretty difficult to join together.
- Welding equipment that is easy to control, operate, and maintain
Frequently Asked Questions
Are joints and welds the same?
Joints differ from welds. The five main joints in welding are:
- Butt joint
- Lap joint
- Corner joint
- Edge joint
- Tee joint
How do I identify a good weld?
The primary sign of a good weld is uniformity. A good weld has excellent penetration and uniform heat transfer, indicated by the bluish heat marks on the metal workpiece.
What type of welding is most beginner-friendly?
MIG welding is beginner-friendly because it is effortless to learn. MIG welders use a wire that runs through the entire machine quickly, making the welding process consistent and fast.
What are the different types of welding processes?
flux cored arc welding FCAW
metal arc welding GMAW
metal arc welding SMAW
Tungsten arc welding GTAW
Welding it Together
Here you have it; the various types of welding designed to meet different needs. From DIY projects to heavy-duty industrial work, you can always trust the above list of weld variations to be ideal for various situations.
The key focus in choosing what type of weld is best for your project is the uniqueness of each type. While some welds are cost-effective and ideal for backyard tasks, others require some level of expertise to create.
What factors determine the best weld for your project? Well, it depends on what you want and how you want it done. As you gain experience with various tasks, you will know.
In addition to choosing the proper weld for your daily project, below are a few safety rules to adhere to:
Always be sure that the welder and tools are in good working order
Do not weld if there's not enough ventilation
Ensure you are wearing PPE
Weld only in areas that are fire safe.
