Dish end thickness: 20 mm ( nominal ), seamless dish.
Heat treatment : Stress relilved due to fiber elogation exceeding 5% only for dishends.
PWHT of vessel : Not required.
Kindly let me know ,in view of above data, whether we need to mark PHT on the name plate ?

Yes and you need to mark as HT not PHT

[quote="djmc"]Dish end thickness: 20 mm ( nominal ), seamless dish.
Heat treatment : Stress relilved due to fiber elogation exceeding 5% only for dishends.
PWHT of vessel : Not required.
Kindly let me know ,in view of above data, whether we need to mark PHT on the name plate ?[/quote]

I would not stamp PHT (Note PHT means Part Heat Treated, whilst HT applies only when the entire item is Heat Treated) because the SR of the head is a fabrication requirements. But it is not so clear, other opinions are welcome.
Mauro

djmc,

If the complete vessel or any part of it is not "post weld heat treated", HT (or PHT) marking is not required on the nameplate.

What type of heat treatment was done on the head to satisfy UCS-79(d)?

dr. chris

Dr Chris,
The heads are only stress releived, In this case pls let me know whether the name plate is required to be stamped with PHT or not .Appriciate your immediate reply.

djmc

As I understand it, the heads were stress relieved prior to welding on the vessel shell. Therefore, PHT stamp is not required.

Article UG-116(f) refers to UW-10 regarding Heat Treatment. UW-10 is called "Postweld Heat Treatment", which means heat treatment after fabrication welding.
Therefore, in my opinion, the "HT" or "PHT"-marking is applicable for heat treated fabrication welds (see also UCS-56), while UCS-79 is a fabrication condition.

Regards Tobias

In one of our case where Pad plate (Large opening) thk crossed 38 mm we gone for PHT stamp as guided by AI.

_________________
Niraj

and it Could be same for dished head also..

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Niraj

UG-116(f) clearly states the "WELD" for the HT and PHT stamp, hence a seamless head will not require for PHT stamp.

Very well. I totally agree with this interpretation. It is very clear in the Code. Mauro

In our work, we have established the policy to require no PHT stamping, but to require the stress relieving heat treatment be reported on the MDR. Up to now, this has worked great.

DK

That was because your AI agree with this. Other AI may not agree with. The MDR should always match the Nameplate stamping. In my opinion, HT should not be reported on the MDR either. It will be good enough once it is reported on C of C for the head.

Tony,

I do not quite agree with you: The nameplate shall reflect the CODE required PWHT, where the MDR shall list also the HT condition of the formed head, etc. You can have a smless head normalized after forming (due to fiber elongation), welded (w/o PWHT) to the rest of the vessel. In this case the MDR should clearly say what was done, but I would not insist on a PHT marking.

Any comments?

DK

I said previously that Name Plate to be stamped only as safety precaution and still I feel that name plate to be stamped as HT since you are not loosing anything. MDR should be specified about Head HT clearly. It is very much sure that in case of repair or alteration for this vessel, then anyone will refer MDR and not refer only stamping.