Monday, August 25, 2008

[MW:1059] Impact testing at -29 deg c and warmer

Dear members,
As per PV code ASME SEC VIII Div 1,impact test is not mandatory for PV
materials for P 1 and Gr1 &2 materials upto thk of 1" for majority of
materials.However for high Pressure Natural Gas applications say 100
Bar design pressure,it is asked to do impact testing at -20 deg C for
materials like A333GR6/A350LF2CL1 materials.Inspite of having
satisfactory values at testing temperature of -45/-46 deg C,testing at
-20 deg C is insisted.Can anyone explain logic behind this?

Further,it may please be noted that as per:
UCS 66(c)-no impact testing is required for B16.5 flanges of ferritic
steel when used at MDMT not colder than -29deg C and;
UCS 66(d)-pipe size 4" and below(P NO 1),impact test exemption is
there as a function of Yield Stress for temp -104 Deg C and warmer
e.g. 20 ksi to 30 ksi-6.0mm thk.Which implies that for 6.0 mm thk pipe
of 4"NB and below,no impact test is mandatory for tempr upto -104 deg
C.
However for Natural Gas applications,for material like A106GR B/A105
materials,impact test at 0 deg C is insisted for sizes 2"NB and above.
Here again,can A106GR B/A105 materials be safely used without impact
testing upto -29 deg C?
Regards
Aarpee

--~--~---------~--~----~------------~-------~--~----~
To post to this group, send email to materials-welding@googlegroups.com
To unsubscribe from this group, send email to materials-welding-unsubscribe@googlegroups.com
For more options, visit this group's bolg at http://materials-welding.blogspot.com/
The views expressed/exchnaged in this group are members personel views and meant for educational purposes only, Users must take their own decisions w.r.t. applicable code/standard/contract documents.
-~----------~----~----~----~------~----~------~--~---

No comments:

[MW:34820] RE: 34813] Clarification in Rate of heating and cooling.

Hello,   Please see the response below.   Regards.   P. Goswami, P. Eng, IWE.   From: materials-welding@googlegroups.com <materials-weld...