Calculating of MAWP

[MohdYaseen2010]

With respect to calculating of MAWP for ASME VIII vessel after specifying it’s nominal thickness, I found two concepts;
One stating that the MAWP shall be calculated using nominal thickness & another specifying Corrodd nominal thickness (nominal thickness - corrosion allowance), I think is the latter is right? What do you think.

Mohd Yaseen

 

[SnTMan]

The latter (MAWP, Hot & Corroded) although often MAWP (New & Cold) is wanted in which case do not deduct CA, use ambient allowables. May be called MAP.

Regards,

Mike

The problem with sloppy work is that the supply FAR EXCEEDS the demand

 

[mk3223]

IMO, it's the engineering references used at the different stages of the equipment. It needs to be clear to state that the MAWP value provided with the vessel conditions either "New & Cold" or "Existing & Corroded".

 

[MohdYaseen2010]

Dears

Thanks for your feedbacks, however neither in the DST nor in vessel Nameplate no one will mentioned whether (new/old MAWP) or (Existing/Corroded MAWP).

Mohd Yaseen

 

[david339933]

MAWP is corroded. UG-98, App. 3-2 definitions. As Mike stated, sometimes New & Cold is also given for information. Code MAWP is hot/corroded.

 

[r6155]

1)MAWP in nameplate is corroded and hot – See example in PTB-4

2) MAWP in UG-99 is for the thickness of material tested (new and cold).

Regards
r6155

 

[MohdYaseen2010]

Dear all,

Thanks for your feedback, however, which one of those (new, corroded, etc) is going to be specified for MAWP in the DST.

(Dear r6155) sorry but what you mean by PTB-4?!

Mohd Yaseen

 

[r6155]

Sorry MohdYaseen2010
PTB-4
ASME Section VIII - Division 1 Example Problem Manual
(465 pag in pdf, 2013 edition)

Regards
r6155