Recent content by chevproe

Hi c8829, Nominal thickness to be considered for determining Radiography requirement is defined in Code para UW-11(g). I have reproduced the Code paragraph hereunder : So, for your case, the nominal thickness is 32mm. As per UCS-57, nominal thickness above 32mm shall mandatorily require full...

Hi TomBarsh... You explained it quite nicely....thanks a lot.. To rephrase the question by OP... Considering if UCS-66(b)(1)(c) was applied, and the ratio for nozzle neck is found to be less than 0.35. In such a case, will the flange be exempt to -155F?? Does the -55F limitation from...

Tankman64, My initial post was aimed at providing you a simplified explanation for UCS-66(b)(1)(c)...i really didnt check in detail the application of this clause.. Could you provide some more data ragrading your vessel...such as Design pressure & Temp, MDMT, Size, Material etc.

Hi Tankman64, UCS-66(b)(1)(c) simply states that instead of using the coincident ratio for allowable reduction in MDMT, you can use the MDMT reduction applicable to the neck or shell to which the flange is attached. So, no need to calculate any ratio, just apply the MDMT reduction of the...

r6155, Did you check API 660(9th Ed.),Par. 9.10.5??

r6155, The Exchanger under discussion is cladded on tubeside only, not on shell side.

c8829, Further to the above, did you consider UCS-66(b)(2)?? Impact testing is required for all materials when MDMT is lower than -48C, unless exempted by UCS-68(c) or if the coincident ratio is 0.35 or lower (for MDMT from -48 till -105). However, for the case stated above, none of the...

TEMA and API specifically prohibit any grooving in the clad portion. However, you may need to consider the fact that Codes always stipulate only the bare minimum requirements, and the actual technical requirements are specified by the End user in the form of Project specifications. Did you...

c8829, Sorry for late reply on this post..i just came across a simialr situation recently... I would tend to agree with your interpretation...UCS-68(c) exemption cannot be claimed when resulting exemption temperature is colder than -48(-61 for your case) and PWHT exemption as per UCS-68(b) is...

You can install a blind on the existing 3" nozzle and make a 2" opening on the blind flange and then weld the 2" nozzle neck and flange onto the blind. You can check the nozzle reinforcement calculation for blind flange as per UG-39 of Code.

Hi Krishsar, I would also tend to agree with SnTMan that we just can't increase the buckling allowable stress arbitrarily without any sound basis. Your AI may differ and ask you for the technical justification of going for higher allowable. You may go for multiple trials with decrease in baffle...

Thanks for your response...TGS4... Whilst I understood that creep fatigue analysis shall be required to be done by an expert, i was trying to understand why Code has placed a limitation on maximum permissible temperature for Vacuum conditions (i.e. 425-C for Carbon and Low ally steels). Coudl...

Hello everybody, I have a question regarding the consideration of Design temperature for Reactor whose details are as per mentioned below : Design temperature (Int.) : 454°C Vacuum condition : (-)0.1MPag @ 454°C Base Material : 2.25Cr-1Mo-V (SA -336 F22V) Design code : ASME Sec VIII Div. 2...

In absence of any clear directive from Code on this issue, I would go the conservative way and consider 21 Ksi. I would request the stalwarts in this forum to share their opinions.