Repair of surface defects in welds by chipping, grinding and gouging is permitted provided the thickness is not reduced below the minimum required. Removal of defects shall be verified by magnetic particle or liquid penetrant examination.
Major defects in weld and base metals, shall be repaired after a written procedure for each individual repair has been approved by OWNER. The written procedure shall include a sketch detailing extent and location of the defect, how defects will be removed, how removal will be verified, qualified welding procedure to be used, subsequent heat treatment and non-destructive examination.
The following are the definitions of major and minor defects:
Major Defects:
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Base Metal
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Weld Metal
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Crack
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Crack, except crater cracks
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Repair Cavity greater than 65 cm2 (10 in2)
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Repair Cavity greater than 65 cm2 (10 in2)
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Repair Cavity deeper than 50% of thickness or 12.7 mm (1/2"), whichever is less
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Repair Cavity deeper than 50% of thickness or 12.7 mm (1/2"), whichever is less
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Weld Build-Up to correct manufacturing error*
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Lack of Fusion and/or Penetration
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Edge defects greater than 25 mm (1") deep, or "t", whichever is less
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Edge defects greater than 20% of edge length
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