Throat thickness of fillet weld
The fillet weld throat is the maximum depth of a right triangle within the weld. It determines the load-carrying capacity and hardness of the joint.
Physical-Chemical Mechanism of Action
The fillet weld throat (FWT) is a geometric parameter that defines the maximum depth of a right triangle in the weld. It directly affects the strength and hardness of the joint.
Metallurgical Relevance & Risks in Welding
A throat that is too small can lead to brittleness and cracks because the joint is not strong enough. A throat that is too large increases hardness and can cause hot cracks or lack of fusion if the welding process is not controlled properly.
Workshop Practice & Instructions
The throat should be between 0.5 mm and 1.0 mm, depending on the material used and the desired hardness. For high-carbon steels (e.g., HSS), the throat should not exceed 0.8 mm to avoid hot cracking. For lower carbon content, the throat can be up to 1.0 mm.