steel casting (ASTM A148 105/85) repair

Date 10-09-2009 06:18

I need to repair some linear defects on new A148 105/85 steel casting. During excavation of defects by arc-air gouging new cracks develop (confirmed by magnetic particle inspection after slow cooling). The local preheat temperature applied is 250°C. What would be the main reason for non-stop cracking cycle and how to approach the repair work. By the way, it is a heavy wall (50-70mm) spindle and some cracks go all the way through the wall. How to get out of this vicious circle (crack-preheat-gouge-slow cool-inspect-new crack-and on and on ...)? Thanks for your help

By Superflux (****)

Date 10-09-2009 16:30 Edited 10-09-2009 17:12

zambrota,

If you are using Dry Mag powder, then maintain preheat during gouging, clean-up and inspection. This should help retard new cracks forming.

Another alternative would be to perform a full Post Weld Heat Treatment Before MT whether it be wet or dry mag.

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