Weld burrs

Weld seams should be continuously smooth, and free from porosities and blow holes, projections and burrs. These should be smoothened out by grinding. See figure 4.2 below. 

Poor workmanship and defective materials can increase corrosion. Water turbulence effects can be increased by poor workmanship, such as the failure to ream burrs from cut ends of copper pipe. This increases the turbulence at the joints and results in erosion of the copper. Excessive and corrosive flux used in soldered coppers joints results in pitting corrosion along the flux runs. Incomplete longitudinal welds in electric resistance welded (ERW) steel pipe result in concentration cell corrosion and rapid corrosion. 

Thorough finishing or smooth grinding of welds is of prime importance for securing a sound, clean surface. Specify the removal of flux, weld metal spatter, welding residue, burrs, and other similar surface defects, whenever possible, prior to any type of overall surface cleaning. 

Unless the specified cleaning operations on their own can automatically provide for the following, the removal of burrs, notches, flares, fluxes, weld metal spatter, etc., should precede the specified surface cleaning. 

The use of flame plasmas, see Figure 2.3, can compromise the barrier-to-adhesion effect of mold release agents, impart higher surface polarity and oxidation levels, as well as reduce the visual appearance of thin weld lines, flow lines, and flash burrs prior to decoration. 

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