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    Welding Heat Input Calculator (kJ/mm)

    What is the welding heat-input formula?

    A standard estimate is H(kJ/mm) = ((V × I × 60) / (S × 1000)) × η, where V is voltage, I is amperage, S is travel speed in mm/min, and η is thermal efficiency. The calculator converts in/min to mm/min automatically when needed.

    Run the numbers for your project

    Use the Welding Heat Input Calculator (kJ/mm) to get an exact answer for your inputs.

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    Related questions

    Estimates and general guidance only. Verify against your local code and AHJ before any installation. Gas, electrical, and refrigerant work is hazardous to untrained users.

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