Preheat Temperature Calculator
Preheat estimate from CE and combined thickness (EN 1011 style).
Preheat slows cooling so hydrogen escapes before the joint hardens. Measure 75 mm from the joint with a temp stick, on the OPPOSITE face — surface-only warmth fools everyone.
Formula
Note: Screening estimate — code methods (graphs in EN 1011-2/AWS) govern for qualified work.
Preheat Temperature Calculator is a free preheat temperature for welding engineers, fabricators and CWI inspectors — instant, accurate and 100% client-side, with the governing formula and reference shown next to the result so the number can be defended, not just quoted.
About Preheat Temperature Calculator
Preheat estimate from CE and combined thickness (EN 1011 style). The calculation implements T_p ≈ 350·√(CE−0.25) + thickness & hydrogen adders (Seferian-style) (EN 1011-2; Seferian; AWS D1.1 Annex XI). Preheat slows cooling so hydrogen escapes before the joint hardens. Measure 75 mm from the joint with a temp stick, on the OPPOSITE face — surface-only warmth fools everyone.
How to use Preheat Temperature Calculator
- 1Enter Carbon equivalent (IIW).
- 2Enter Combined thickness (sum at joint) in mm.
- 3Enter Hydrogen scale (1 low-H (≤5 ml) · 2 medium (5–10) · 3 high (cellulosic/rutile)).
- 4Read Suggested preheat instantly — no submit button needed.
- 5Need US units? Flip the SI/Imperial toggle and every field converts.
Why use Preheat Temperature Calculator?
- ✓Implements the standard formula — T_p ≈ 350·√(CE−0.25) + thickness & hydrogen adders (Seferian-style)
- ✓Reference cited on-page: EN 1011-2; Seferian; AWS D1.1 Annex XI
- ✓One-click SI ⇄ Imperial toggle — values convert in place, physics stays in SI
- ✓Live worked example: the substitution recomputes from your numbers
- ✓Runs entirely in your browser — nothing uploaded, free forever
Frequently asked questions
What formula does the Preheat Temperature Calculator use?+
It computes T_p ≈ 350·√(CE−0.25) + thickness & hydrogen adders (Seferian-style), per EN 1011-2; Seferian; AWS D1.1 Annex XI. The formula is displayed under the result along with a worked example substituted with your own inputs.
What should I keep in mind when using this calculator?+
Preheat slows cooling so hydrogen escapes before the joint hardens. Measure 75 mm from the joint with a temp stick, on the OPPOSITE face — surface-only warmth fools everyone. Note: Screening estimate — code methods (graphs in EN 1011-2/AWS) govern for qualified work.
Does this follow AWS/IS welding codes?+
Each tool implements the formula from the cited code or handbook (AWS D1.1, IS 800, ISO/EN). Qualified WPS values always govern over any calculator for code work.
Is the Preheat Temperature Calculator free to use?+
Yes — completely free, no sign-up, no limits. It runs client-side in your browser, so inputs stay private and results are instant even on slow connections.
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