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This causes serious issues in pipes because corrosive substances can settle in these areas. These types of defects occur when the welding procedures are not adhered to; possible causes include the current setting, arc length, electrode angle, and electrode manipulation. [23] Defects can be varied and classified as critical or noncritical.
In welding, undercutting is when the weld reduces the cross-sectional thickness of the base metal. This type of defect reduces the strength of the weld and workpieces. One reason for this defect is excessive current, causing the edges of the joint to melt and drain into the weld; this leaves a drain-like impression along the length of the weld.
Arc blow tends to occur if the material being welded has residual magnetism at a certain level, particularly when the weld root is being made, and the welding current is direct current (DC positive or negative). Magnetic arc blow is popularly attributed to a change in the direction of current as it flows into and through the workpiece.
During welding, joints are formed between two or more separate pieces of material which can introduce defects or residual stresses. Under cyclic loading these defects can grow a fatigue crack, causing the assembly to fail even if these cyclic stresses are low and smaller than the base material and weld filler material yield stress. [1]
These are called inclusions and are a form of welding defect. Inclusions may be visible on the surface after cleaning, or may be completely contained within the metal, in that case they can only be detected on X-rays of the weld, requiring grinding or drilling to remove (followed by re-welding that section).
Amongst these, tunneling defect is the most common defect in DFSW resulting from improper material flows throughout welding. It is mainly attributed to inappropriate selection of welding parameters particularly welding speed, rotational speed, tool design and tool penetration leading to either abnormal stirring or insufficient heat input. [18]
BMW recalled certain 2023-2024 X1, X5, X6, X7, XM, 530i, i5, 740i, 760i, i7, and 750e vehicles.. The NHTSA report said that the integrated brake system may malfunction and result in a loss of ...
The typical welding defects (lack of fusion of the weld to the base metal, cracks or porosity inside the weld, and variations in weld density) could cause a structure to break or a pipeline to rupture.