Rig Fab Educational Services
Welder’s Handbook
Incorrect Shape A groove at the toe or root of a weld either on the weld face or in previously deposited weld metal. Undercut
Weld metal applied to the surface of a weld producing reinforcement greater than that specified. Also referred to as excess weld metal (butt weld) and excess convexity (fillet weld). Excessive Weld Reinforcement
Excessive amperage Too long an arc length
Causes:
Causes:
Incorrect welding parameters. Weld energy input too high. Travel speed too low. Size and type of electrode and welding position. Incorrect welder technique.
Excessive weaving of the electrode. -Too fast a rate of travel. - Angle of electrode too inclined to the joint face Result: A stress concentration site and a potential site for fatigue
Result: Increased distortion and reduced fatigue life.
Undercut
Undercut
An imperfection at the toe or root of a weld caused by metal flowing onto the surface of the parent metal without fusing to it. Overlap
Overlap
Overlap
Incorrect rate of travel. Incorrect “angle of approach”. Too large an electrode size. Too low an amperage.
Causes:
Overlap
Result: Has a similar effect as undercut and produces a stress concentration site due to the unfused weld metal.
18
Made with FlippingBook Ebook Creator