Visual Inspection First
Many weld defects that matter — undercut, porosity, incomplete fusion at the toe, excessive spatter — are visible to a trained inspector before any non-destructive test is run, and IS 822 sets out visual inspection as a distinct stage of weld inspection.[1]A disciplined visual inspection against the approved weld procedure, done on every structural weld rather than a sample, catches problems at a fraction of the cost of instrumented testing.
Choosing the Right NDT Method
IS 822 lists ultrasonic, radiographic, magnetic particle and dye penetrant testing among its non-destructive methods.[1]Ultrasonic testing finds subsurface defects in thicker sections that visual inspection can't reach, while dye penetrant and magnetic particle testing are better suited to surface-breaking defects on thinner welds. Radiography gives the clearest record but is slower and carries safety and access requirements that make it impractical for most site welds outside of critical, code-mandated locations. Specifying the wrong method for the defect type wastes budget without closing the actual risk.
Reading the Result, Not Just Filing It
An NDT report that sits in a file without being reviewed against acceptance criteria by someone qualified to interpret it isn't quality control, it's paperwork. The reviewer needs to compare each indication against the applicable code's acceptance limits and make an explicit accept/repair/reject call — not just record that a test was performed.
Sources
- IS 822:1970 Code of procedure for inspection of welds — Bureau of Indian Standards
- What it says:
- Sets out visual inspection of welds (clause 7.1) and non-destructive methods including ultrasonic, radiographic, magnetic particle and dye penetrant testing.
- Rights:
- Bureau of Indian Standards copyright; clause cited, text not reproduced (copy published by Public.Resource.Org under the Right to Information Act, 2005)
- Retrieved:
- 2026-09-23