Throat thickness
Throat thickness is the minimum height of the triangle that fits into the cross-section of a fillet weld. It determines the minimum weld size and affects the strength and toughness of the joint.
Physical-Chemical Mechanism
Throat thickness is a geometric dimension that defines the cross-section of a fillet weld. It influences welding by affecting distortion and cooling of the material.
Metallurgical Relevance & Welding Risks
Too thin a throat can lead to fracture and cracks because the material is not strong enough. Too thick a throat increases stress in the weld and raises the risk of hot cracking and weld defects.
Shop Practice & Instructions
For a safe fillet weld, the throat thickness should be at least 1.5 times the thickness of the thinner member. For high-carbon steel (e.g., >0.6% C), it should be at least 2 times the thickness. Always check specific requirements and prepare carefully before welding.