A welding joint is the connection or joining of two metals using a filler such as a solder, brazing material, braze alloy, welding rod and/or metal powder.
There are many types of joints that can be used in construction and design to meet specific requirements for strength and durability. The type of joint chosen will depend on factors such as material composition(s), application(s) and environment.
Whether you are a novice or expert when it comes to welding, there are always new ways to learn about this process. A good place to start when choosing the right weld is understanding the different types of welding joints available.
We’ll be discussing the various types of welding joints that exist and what they’re used for. Welding is an art form in itself, so let’s dive into these fascinating joints.
Table of Contents
What is a Weld Joint?
The weld joint is the connection of two metals, with a filler material which can be either gas (welding torch), liquid (electrode wire), or solid (filler metal), but most often welding is done by bringing two or more pieces together to form one.
This process requires high heat and materials that are not easily melted will need to be heated before they can become fluid enough to flow into the cavity between the pieces. Many types of joints are typically very strong, lasting far longer than any other type of joining method for metals.
Welding is done in many industries all across the world for many purposes including creating products at factories, agricultural maintenance on farms, construction jobs like building bridges and buildings, along with many other jobs that require the joining of two metals.
It’s important to have an understanding of how many different types of welding joints you will encounter when trying to join metals together. This guide will teach you about all the different types, shapes and forms that welding joints can take, so you can recognize them when placed in front of you.
Different Types of Welding Joints
There are many different types of welding joints available and though they may look similar, each one is designed and built for a very specific purpose. Each joint has its own set of pros and cons. Here we’ve listed the most common types of welding joints: butt, corner, T-joint, lap joint, corner lap joint, edge joint (dovetail) and fillet welds.
1. Butt Joint Welding
This is a weld joint where the joining pieces meet flat, or nearly so, on their ends. The resulting weld has a width equal to the thickness of each sheet metal used. The following are examples of styles used to create butt joints:
- Square
- Single bevel
- Double bevel
- Single J
- Double J
- Single V
- Double V
- Single U
- Double U groove
2. Corner Joint Welding
A corner welding joint intersects sheets at an angle rather than a flat surface. The following are examples of styles used to create corner joints:
- Spot weld
- Fillet weld
- V-groove weld
- Square-groove weld or butt weld
- U-groove weld
- Bevel-groove weld
- Flare-V-groove weld
- J-groove weld
- Corner-flange weld.
- Edge weld
3. T-Joint Welding
In T-joint welding, one piece is placed perpendicularly over another creating a right angle intersection between them at their corners. The following are examples of styles used to create T-joints:
- Plug weld
- Fillet weld
- Bevel-groove weld
- Slot weld
- Flare-bevel-groove weld
- J-groove weld
- Melt-through weld
4. Lap Joint Welding
A lap joint requires two adjoining materials butted together face to face with excess material bent over on both sides of the joint to form extensions that are equal in size. The following are examples of styles used to create Lap joints:
- Slot weld
- Plug weld
- Bevel-groove weld
- Spot weld
- Flare-bevel-groove weld
- J-groove weld
5. Corner Lap Joint Welding
This joint is similar to the lap joint but it has an additional extension on one side which overlaps the edge of the other sheet metal making this particular joint stronger than a regular lap joint. The following are examples of styles used to create Corner Lap joints:
- Spot weld
- Fillet weld
- V-groove weld
- Square-groove weld or butt weld
- U-groove weld
- Bevel-groove weld
- Flare-V-groove weld
- J-groove weld
- Corner-flange weld.
- Edge weld
6. Edge Joint Welding (Dovetail)
The dovetail welding joint requires two adjoining materials with flanges (extensions) on each end, allowing for them to be joined together at their edges by overlapping one onto another. The following are examples of styles used to create Edge or Dovetail joints:
- Bevel-groove weld
- Square-groove weld or butt weld
- J-groove weld
- V-groove weld
- Edge-flange weld
- U-groove weld
- Corner-flange weld
7. Fillet Welds
A fillet weld is often used where there is no corner or edge available to assist in joining metals together; this type of weld joins three or more pieces at an angle when no corner exists. The following are examples of styles used to create Fillet joints:
- Casting
- Shearing
- Machining
- Forging
- Filing
- Stamping
- Oxyacetylene cutting (thermal cutting process)
- Routing
- Grinding
- Plasma arc cutting (thermal cutting process)
Conclusion
The different welding joints are formed for many different reasons and each one is used to accomplish a specific purpose. Each joint has its own set of advantages and disadvantages depending on the circumstances, but all in all, if you learn about each type of welding joint before the weld starts it will make your welding process much easier from start to finish.