back some other comments about this qualification.
You may not have an issue with ASME Section IX and chemistry matching
as much as some other issues. The filler wire is a "G" classification
in which the chemistry is not required and only needs to meet the
requirements of one of the elements. How will the supplier
demonstrate that the wire will meet the clients requirements for the
filler metal chemistry? The NACE MR0175 has a nickel restriction of
1% max. I would expect that the suppler will be supplying a weld
metal chemical analysis with the test plate or actually running an
undiluted filler metal chemisty test to demonstrate the wire meets the
clients requirements before proceeding with the test plate.
Why are they selecting a filler wire with a minimum tensile of 90 ksi
vs the 60 ksi max on the A516 Gr 70. It is permissble to do this, but
your weld metal has about 50% higher tensile strength than the base
material. This is usually not a good practice since normally it is
good practice to match the strength of the filler with the base
material. Seems like a 7018 rod with a matching SAW wire would much
more easily meet the requirements of hardness, chemistry, and have
less issues with hydrogen cracking, etc.
Its seems like it will be difficult to meet 200 HB in the weld metal
with a 90 ksi filler wire with a 610C post weld heat treat. However,
maybe they have some experience with this wire strength. I would be
very interested in the vickers hardness results of the crossection and
the Brinell hardness test of the weld surface.
Are there any impact requirements? The G classification does not
specify impacts. If impacts were required, I would only approve the
heat that was tested.
In the end, if the supplier wants to run the test plate and he can
demonstrate he can meet all of the requirements such as weld metal
chemistry, 200 HB max weld deposit hardness, 250 HV HAZ hardness,
bends, tensiles, impacts, then go ahead and let them proceed. But
seems like there is a much easier path.
Please, just my opinions and I have seen many things done that people
have said can't be done......would be very intereted in the results of
the testing.....
On Aug 23, 2:51 pm, "Aly" <mhaskar....@gmail.com> wrote:
> Dear All,
> We are getting Heads for pressure vessels from Supplier in Saudi, The head
> requirements are as follows:
>
> Head: 28mm thk; SA516 Gr 60, NACE MR 0175 & HIC tested NACE TM 0284
> Construction Code ASME SEC VIII Div 1, E2007 Ad2009.
> Type of Head Ellipsoidal with chordal seam (U stamped)
> Service For Pressure vessel in Sour Service
> HT: Normalization at 910deg C for after forming & SR at 610 deg C along
> with vessel.
> Chemistry restriction by Client: C= 0.06% Si=0.24%, S= 0.007 & P=0.015,
> Hardness 200BHN
> Simulation Testing for HT (NR+SR) on test plate required.
>
> Now the supplier has submitted me WPS / PQR for welding chordal seam of head
> for my review, the details of PQR as follows:
> Base metal SA516 Gr70; 90mmthk
> SMAW with E9018-G; SFA 5.5; A=10; F no. 4
> SAW with F9P6 EG F3; SFA 5.23; A=10; F no. 6
> HT= NR+SR
>
> The weld metal composition achieved on PQR for SAW process are C=0.06%, Mn=1
> 37%, Si=0.24%, S% <0.005, P=0.014%, Mo=0.48%, Ni=0.82%, Cu=0.13%.
>
> Tensile& bend test meeting requirements of Base metal.
>
> My Question is whether the proposed filler metal is acceptable to this base
> metal (SA516 Gr 60) as per ASME SEC IX as weld metal chemical properties are
> not meeting the base metal requirements.
>
> Thanks for co operation in this regard
>
> Aly
> Kuwait
>
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