ISO standard · reference card
Does ISO 17640 govern the ultrasonic examination in front of you? Scope decision flow for the manual UT standard, the codes it is read with, and the records that support the result.
ISO 17640 is a technique and testing-level standard, not an acceptance standard. It says how to perform manual ultrasonic examination of a fusion-welded joint and how thoroughly, through the testing level the application standard assigns. Its core levels are written for ferritic, full-penetration joints above the standard’s thickness floor. It does not say whether the joint passes — that answer comes from the quality-level or acceptance standard the contract names, read alongside the finding.
The distinction matters at the procedure-writing stage. A specification that calls for “UT to ISO 17640” without a testing level and an acceptance reference has named a technique without setting the extent of the examination or the bar the result is judged against, and two inspection bodies can scan and report it differently.
The second recurring confusion is scope creep past the core levels. Non-ferritic materials, partial-penetration joints and automated equipment sit inside ISO 17640 only when the specification invokes testing level D — neither excluded outright nor covered by default. Austenitic, nickel-based, duplex and dissimilar welds fall outside its core scope and are examined under ISO 22825 instead; phased array procedures typically run under a dedicated standard such as ISO 13588 rather than under ISO 17640 directly.
Therness equipment does not perform ultrasonic examination. It produces the process-side evidence next to it: which welds ran inside the qualified window, a continuous thermal record flagging which joints deserve the closest look, and a traceable identifier tying an eventual scan result to the exact weld it came from. Pair this entry with the ISO 5817 acceptance-level card and the ISO 6520-1 classification card for the two questions a scan result still needs answered.
| Question | If yes | If no |
|---|---|---|
| Does the application or construction standard call up ISO 17640 for this joint? | Work to the technique and testing level it names, or the level the application standard assigns by default. | Confirm which UT standard the contract invokes before writing a procedure — several regional standards cover the same ground differently. |
| Is the joint ferritic and full penetration, examined manually, at or above the thickness the standard's core levels cover? | ISO 17640's core levels apply directly. | It sits inside ISO 17640 only if the specification invokes testing level D. Austenitic, nickel-based, duplex or dissimilar welds fall outside this standard — check ISO 22825 instead. |
| Do you know the testing level the job requires? | Use it to set scan coverage and reporting extent — the level changes how much of the weld gets examined, not the acceptance criteria. | The application or product standard assigns the level. Settle that before scanning. |
Conformity is decided by inspection and testing against the criteria the standard and the contract set. The records below are evidence that the process was held where it was qualified; they support an inspection result, they never replace one.
| Requirement | Record produced | Source |
|---|---|---|
| Targeting scan effort at the joints most likely to carry a planar imperfection | Continuous thermal record of each seam with per-weld anomaly flags | HeatCam IR-C |
| Tying a scan result back to the exact weld, pass and operator it examined | Per-weld process record joined to a weld identifier at acquisition time | WeldTrace |
Therness records what the machine actually delivered on every weld — parameters, thermal signature and a per-weld trail — so a conformity argument rests on measurements instead of recollection.
Progetto cofinanziato nell'ambito del PR Piemonte FSE+ 2021-2027,
Priorità I, Obiettivo Specifico a), Azione 4 – "Sostegno alla nascita delle start up"
