1) In general, PWHT tempers the weld metal and HAZ that has formed martensite on high strength low alloy weld metals from fast cooling, while also relieving residual stresses. Both tempering and stress relief can be beneficial, but tempered martensite is not as strong as untempered martensite...
1) Yes
2) If you thought the 3.3mm specimen was in question, wouldn't the 1mm specimen make it worse? Besides, there is no standard specimen at 1mm anyway, that's too thin. 2.5mm (.099") is the smallest specimen recognized by ASME Section VIII. Anything below that thickness is exempt from...
The arc is somewhere around 10,000 degrees F with either method, so it sufficiently heats and melts the base metal with either method. The main difference is for keyhole welding, which you aren't doing.
PAW can be transferred or non-transferred.
Whether the process is transferred or non-transferred is dependent on the welding current circuit. For transferred, the circuit/arc goes from the torch to the workpiece. For non-transferred, the circuit/arc does not go though the workpeice, but from...
Is the casting heat treated after welding? Stress relief PWHT will reduce the property differences, and normalizing PWHT will make the weld softer than the casting. In the as-welded condition, you will have the biggest property differences and machining issues. Do you know the heat treat...
You don't have to match the strength of the higher strenght member in dissimilar strenght joints in all the codes I've welded to. If you meet the strength of the S355NL while welding it to 4130, you should be fine.
In theory, a pressure test may be able to produce slight deformations, as residual welding stresses when present can be up to the yield strength of the material. When you hydro test, if the residual stresses are within 100MPa of the yield strength, you could get yielding in those locations...
Section IX is a service code. It supports the construction codes, such as III, VIII, or B31.X. The construction codes can use, modify, add to Section IX as they see fit. In the case of B31.3 it's modifying the requirements of Section IX.
Now I feel justified to have hung onto my Garmin program they don't support anymore that keeps all of my data on my own computer, rather than having to depend on their online services. Why does everyone (companies) feel like people shouldn't be able to keep their own data these days?
There aren't off the shelf welding symbols for every conceivable joint. When there isn't, AWS says (paraphrased) that drawings or descriptions other than standard welding symbols can be used. Your drawing looks like you are doing half of a plug and slot weld though.
It is possible given the right steps were made at the beginning and now, but talk to your notified body representative. They may or may not be willing to entertain the request. If not, it's no point in going further.
The welder is supposed to clean the base metal before he welds on it. Most do it with a grinder/sander rather than a chemical. Nothing wrong with that unless it's a contaminated abrasive. Not sure why the elbows were sanded though. However, if you specified a stainless steel that is so...
Are you using a teflon coated liner for welding aluminim? They can help the wire feeding quite a bit. Assuming your issue is really wire feeding, not parameters, then use what Kingnero said: - a torch with an as short as possible cable run (max. 10 ft/3m, preferably shorter)
If that doesn't...
The filler metal can only be classified by what the manufacturer classifies it as. If you test it in a different condition, that is not prohibited by ASME IX or a construction code that I know about, but that doesn't change the classification. So your PQR would just record the classification...
The metallurgical analysis did determine that all the fracture was brittle in nature. No ductile fracture was observed in either crack. To me, that would point to fractures that were not from over-stressing, as he steel would have been at or above the melting temperature of the salt...
EdStainless- yes these were (2) non-PWHT fabrication (pipe butt welds). Thermal cycling result in fatigue (low cycle) cracks from my understanding? These cracks definitely had significant branching (in the weld metal only) and intergranular at least to start with. Wouldn't a thermal...
I'd have posted them initially, but we don't own the photos. I doubt it would be permitted if I asked permission due to the situation. We're just trying to glean some information from this failure to see what we can do to mitigate it for our products (the weld in question was another companies...