Preheating A335 P5
Preheating A335 P5
(OP)
Hello.
It is possible to use propane for preheating A335 P5?
Thank you!
It is possible to use propane for preheating A335 P5?
Thank you!
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS Come Join Us!Are you an
Engineering professional? Join Eng-Tips Forums!
*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail. Posting GuidelinesJobs |
|
RE: Preheating A335 P5
RE: Preheating A335 P5
I was asking because I saw that many companies are doing the preheat with the electrical resistance, and I was wondering if using propane it's a problem due hydrogen content.
I think that if you are using only GTAW, with low hydrogen filler metal and you respect the preheat & interpass temperature, there would be no concern of the preheating method.
Another question is if the heat treatment it's mandatory immediately after welding, or it's possible to postpone it with the condition to make a dehydrogenation (min 1h at 300deg.)?
Also, dehydrogenation it's mandatory if you use a filler metal with low hydrogen content?
Thank you very much.
Have a nice day!
RE: Preheating A335 P5
You can postpone or delay, for a reasonable period, PWHT with a post weld bake (aka dehydrogenation). Before PWHT, I would perform a surface NDT to ensure no cracks in the weld region before the application of PWHT.
If you use low hydrogen electrodes with supplement H4 designation and you follow good preheat maintenance and surface cleaning before welding, you can omit the post weld bake before PWHT.
RE: Preheating A335 P5