Reference
Weldment Reference Library
The things you need open in another tab while you finish a weldment drawing. Free, no email gate, and written so you can check any of it against the standard itself.
Weldment glossary
111 terms from weldment drawings, quotes and inspection reports, defined in plain language and filterable in the browser.
ChartWeld symbols explained
What each weld symbol means, which side of the reference line it belongs on, and the five things buyers most often leave off a drawing.
Selection guideTolerance and quality classes
ISO 13920, ISO 2768, ISO 5817 and EN 1090 execution classes: what each one governs and how to pick the right class instead of the tightest one.
Cross referenceSteel and aluminium grades
Approximate ASTM and EN equivalents for the grades used in weldments, with what each one changes about welding, distortion and machining.
Why we do not reproduce the standards
ISO 5817, ISO 13920 and AWS A2.4 are copyrighted documents. Sites that paste their limit tables in full are redistributing something they do not own, and a table copied badly is worse than no table at all.
What we publish instead is the part that is actually hard: which standard governs what, how the classes relate to each other, and how to choose a class rather than reflexively picking the tightest one. When you need the exact limit, buy the standard or read it through your own organisation.
This and the rest of our sourcing policy are on the editorial standards page.
- Tools, not just tablesThe machining allowance calculator, RFQ checklist and supplier audit checklist run in your browser and send us nothing.
- Guides that go deeperTwenty in-depth guides on cost, process, tolerances and supplier selection.
- Corrections welcomeSomething here wrong? Tell us at and we fix the page and date the correction.
Drawing finished?
Send it and we will match it with shops that weld, stress relieve and machine it in house. Free for buyers, reply within 24 business hours.