We Know Low Alloy steels materials like P4, P5.....requires
Preheat before welding as well as postheating after welding.
As per my client specifications, i need to needs to do 150 deg.C
preheat & 200deg.C postheating for 2hrs.
Query:1. I needs to follow the same thing for tacking?.
2. If GT AW process i use ( No flux/coating involved, No question of diffussible hydrogen level to be dried off after welding)
for tacking, can i eliminate postheating?
3. Is there any other mothods of simplifying/avoiding postheating.
P.Rao
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1 comment:
From my experience there is no need to postheat tacks done by GTAW. We have used preheats as low as 100°C for tack welding P4 and P5 materials and no post heat. Never found a crack.
Thanks. Hope it helps.
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