Permanent joints analysed for shear in the throat of the weld.
Fillet welds are designed on the throat area (0.707 × leg). Stress τ=F/(0.707·h·L). Butt welds carry parent-metal stress. Distortion, residual stress and fatigue of weld toes require attention.
A 6 mm fillet weld, 100 mm long, carries about 30 kN at 100 MPa allowable.
Welded joints are permanent and widely used in frames and pressure parts, so their strength and fatigue behaviour must be checked.
Permanent joints analysed for shear in the throat of the weld.
Welded joints are permanent and widely used in frames and pressure parts, so their strength and fatigue behaviour must be checked.
The shortest distance from the root to the weld face, and it is the section used to calculate shear strength.
The weld toe is a stress concentrator and often contains residual stress, so cracks start there under cyclic load.
Typical applications include designing a fillet weld to connect two steel plates, checking the throat of a weld on a crane boom and inspecting a pipe weld for defects that could shorten fatigue life.
Study "Fasteners and bolted joints" first (topic 91 of 106 in Engineering Mechanics). It covers the groundwork this topic builds on.
Weld symbols on drawings. Throat of weld governs. Heat-affected zone weaker.
A 6 mm fillet weld, 100 mm long, carries about 30 kN at 100 MPa allowable.
The next topic is "Clutches and brakes", which builds directly on this one.
It is classed as Advanced in Engineering Mechanics (topic 92 of 106). It is an advanced topic. It assumes you are comfortable with the intermediate topics in Engineering Mechanics.
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