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we share about welding inspection tips,welding procedures and techniques for SMAW,MIG,TIG,FCAW,SAW and other welding process for stainlles steel and other alloys,equipments,welders,materials,inspector,NDT,NDE.

There are some cause and remedies welding defects : Inclusions Cause:Failure to remove slag, Remedies: Clean surface and previous weld bead Cause:Entrapment of refractory oxides, Remedies: Power wire brush the previous bead

Below some welding defects, Roots Defects : Incomplete root penetration, lack of fusion, Excess penetration bead, Root concavity. (suck-back, underwashing), etc

Many metals must be given heat treatment before and after welding. The inspector's function is to ensure that the treatment is given, and given correctly, to the details supplied.

Most material products contain residual stresses, often up to yield point. Pipe products, for example, are usually very highly stressed. The tendency to develop residual stresses increases when the heating and cooling are localised.

LAMELLAR TEARING. A step like crack that occurs in thick section tee joints and closed corner joints.

The notch that can result from faulty workmanship or from improper design produces an extremely high stress concentration which prohibits yielding.

In the BS system (standard BS 639: 1986) for carbon and carbon manganese steels the electrode may be partially or completely specified by a letter or number.

Inspection by penetrating liquid By means of the inspection with penetrating or technical liquid of penetrating dye, discontinuities can be detected as cracks that enter the surface. A liquid dye is attracted by hair action towards a thin crack, that of another way would be invisible.