Minimum Preheat and Maximum interpass Temp.

[engineermat]

What are the requirements of Minimum Preheat and Maximum interpass Temperature for Aluminum welding, for example ASME SB209-5083 to ASME SB209-5083, or ASME SB209-5083 to ASME SB209-3003

Thanks.

 

[metengr]

There are really no preheat requirements for welding aluminium, which means you can weld at ambient temperature. In some cases for relatively thick-walled aluminum components, preheat may be used to reduce the cooling rate because of the high thermal conductivity of this metal. For thick sections, the maximum preheat AND interpass temperature should be less than 400 deg F.