The method of inspecting welds in structural steel should adhere to IS: 822, and the extent of inspection and testing must be in accordance with the relevant applicable standards. Inspection of welds is necessary during all stages of fabrication and erection for several objectives. Firstly, it is important to check the conformity of welds with the relevant standards and the suitability of various welding equipment and their performance. Secondly, witnessing and approving the welding procedure qualification is essential. This includes verifying that the welding procedures followed are approved and meet the required standards. Thirdly, witnessing and approving the welder’s performance qualification is crucial. This involves ensuring that the welders performing the welds are qualified and competent to carry out the job. Lastly, it is important to check whether the shop or field welding being executed is in conformity with the relevant specifications and codes of practice, ensuring that the welding work meets the required quality standards.
Visual inspection is a critical method for inspecting welds in structural steel. All completed welds, without exception (i.e., 100% of them), must undergo visual inspection to identify any potential defects or faults. These may include surface defects such as blow holes, exposed porosity, and unfused welds. Surface cracks in both the weld metal and the adjacent parent metal must also be identified. Additionally, any damage to the parent metal, such as undercuts, burning, or overheating, must be detected. Profile defects, such as excessive convexity or concavity, overlapping, unequal leg lengths, and excessive reinforcement, must also be checked. Incomplete filled grooves, excessive penetration beads, and root grooves are other profile defects that need to be identified. Distortion due to welding, such as local shrinkage, camber, bowing, twisting, rotation, and warping, must be assessed. Linear eccentricity, angular and rotational misalignment of parts, and dimensional errors must also be inspected during visual examination.
Mechanical tests are another important method for inspecting welds. These tests, such as tensile load tests, bend tests, and impact tests, must be conducted in accordance with relevant standards.
Magnetic particle, dye penetration, and ultrasonic examinations are additional methods used for inspecting welds. These tests are carried out on randomly selected joints using approved procedures in accordance with IS: 822 (the relevant Indian standard).
Radiographic examination is a specialized method used for inspecting welds, and it is only performed in special cases on random joints. The test is carried out in accordance with the procedure outlined in IS: 822 (the relevant Indian standard).