Notes

welding joints

Welding permanently joins parts together using heat, pressure, or friction. The location where two or more welded parts come together is called a joint. There are many different types of welded joints. Designers choose the appropriate joint type based on the required strength of the joint, availability of materials, and safety concerns.

The strength of the weld metal and the amount of joint penetration control the strength of the joint. Additionally, the welder must have easy access to the joint whenever possible. An easily accessed joint improves the welder’s ability to create a high-quality weld, reduces defects, and lowers production costs.



parts of a weld


A weld is the combination of base metals and weld metal. Welding codes help determine the characteristics and dimensions of each component of a finished weld. Welds include five basic components:
Butt Joint Components
Butt Joint Components
Corner Joint Components
Corner Joint Components
The weld face is the exposed surface of a weld. The face of a weld has certain characteristics based on the weld type.
The weld root is the point at which the back of the weld intersects the base metal surfaces. A root opening provides access to the root. The size of the root opening determines how much filler metal the welder needs to obtain good fusion at the root.
The weld toes are the points at which the weld face and the base metal meet. Toes can experience cracking from overlap or undercut if a weld is not completed properly.
The weld throat is a measurement of the distance between the weld root and a line drawn between the weld toes. The length of the weld throat largely determines the strength of the completed weld.
The weld crown extends beyond an imaginary line drawn between the weld toes. In groove welds, the crown is often ground off to create an unbroken horizontal surface.