Wednesday, September 23, 2020

Re: [MW:31502] Re: ASME BPV Sec VIII div1 , UCS-68(b) - PWHT requirements

Yes C and D welds are not exempted. most probably because a geometrical discontinuity is always associated with a C and D weld.

There is also an interpretation relevant to UCS-68(b):

Standard Designation:BPV Section VIII Div 1
Edition/Addenda:
Para./Fig./Table No:
Subject Description:Section VIII, Division 1 (1998 Edition, 1999 Addenda); UCS-68(b)
Date Issued:01/14/2000
Record Number:BC99-597
Interpretation Number :VIII-1-98-99
Question(s) and Reply(ies):


Question: Do the requirements of UCS-68(b) in Section VIII, Division 1 apply to tube-to-tubesheet welds?

Reply: Yes.



Στις Τετ, 23 Σεπ 2020 στις 8:36 π.μ., ο/η MW <raghurambathula@gmail.com> έγραψε:
If a weld joint has a coincident ratio higher then 0,35 then the same need to be PWHT with the following exemptions from PWHT (even if coincident ratio is higher than 0.35):   
Category A and B joints which respect the condition indicated in UCS-68(b)(1) - e.g. 100%RT.
Lightly loaded attachments (<25% stress value) which respect the condition indicated in UCS-68(b)(2)(-a) 
Seal welds (tube to tube sheet)

 It does not exempt from PWHT the category "C" and "D" joints , and fillet welds (except as defined as "lightly loaded attachments" 

On Saturday, 19 September 2020 at 09:01:21 UTC+5:30 MW wrote:
Can you please provide your interpretation for the following requirements of UCS-68(b)
Vessel MDMT - 48 °C , PWHT - not required

In accordance with para UCS-68(b) PWHT is required except for Category A and B joints with 100% RT, lightly loaded attachments and seal welds only.
and it is silent on category C , D welds and other attachments.

Question: does this mean PWHT is required for Category C and D, even though it is exempted for Category A and B welds? then vessel will undergo local PWHT
In my opinion we should not interpret this way and look for only what is code specifies (i.e. if Category A and B or other welds as specified is exempted entire vessel is exempted)  

--
https://materials-welding.blogspot.com/
https://www.linkedin.com/groups/122787
---
You received this message because you are subscribed to the Google Groups "Materials & Welding" group.
To unsubscribe from this group and stop receiving emails from it, send an email to materials-welding+unsubscribe@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/materials-welding/df4bd57b-dfe4-4865-9159-80999d2e474bn%40googlegroups.com.


--
Dr. Georgios Dilintas,
Dipl. Ing. In Aeronautic and Space Engineering
Ph.D in Mechanics of Solids - Computational Mechanics
A.I.S, A.N.I, IRCA Lead Auditor
Welding, Stress Analysis, Corrosion, QA/QC, Failure Analysis, Risk Analysis

--
https://materials-welding.blogspot.com/
https://www.linkedin.com/groups/122787
---
You received this message because you are subscribed to the Google Groups "Materials & Welding" group.
To unsubscribe from this group and stop receiving emails from it, send an email to materials-welding+unsubscribe@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/materials-welding/CAPOi40BVTpjW%2BPJsiOhvT7t5vkfb00NM%2Bc0U8oG0bhhBL-KTHQ%40mail.gmail.com.

No comments:

[MW:34920] Tubesheet Hole step

Hello Team, I have one question any tolerance given for tubesheet Hole step. Please do needful. Regards, AP  -- https://materials-...