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How do you weld grey cast iron using a MMA (SMAW) process?


Frequently Asked Questions

Thin sections (up to 6mm) may be welded at room temperature but preheat (typically 300°C for ferritic and 330°C for pearlitic matrices respectively) followed by slow cooling is preferred where machinability is important, and for complex or thick sections. Use the smallest size of electrode and lowest welding current suited to the application and minimise dilution by operating at low currents. Avoid overheating the workpiece by depositing short stringer beads, which should be peened lightly after each pass and allow the component to cool slowly.

All cast iron welding requires care. If in doubt, contact an experienced practitioner.

Further information is available in:

Welding of cast irons - a guide to best practice

C.L.M.Cottrell, 'Welding cast irons', published by TWI, Abington, Cambridge, UK, 1986 and available from Woodhead Publishing, Abington, Cambridge, UK. e-mail:
ISBN 0 85300 176 6

Guide for Welding Iron Castings - ANSI/AWS D11.2-89, American Welding Society, Miami, Florida, USA. e-mail:
ISBN 0 87171 295 4

See further information on Materials and Corrosion Management, or please contact us.

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