1.Jointers are not applicable to pipe supplier.Pipe is to be converted into a piping spool with Flanges welded to it and spool is to be subjected to Hydro at 1783 psi.
2.75%SMYS is actually indicated for API 5L GR B pipe in API 5L spec under 'alternative 'Hydro pressure.
3.No certification to A106.Constn code is B31.8 but we need to carry out Hydro at a 1783 psi as a specific case and a special requirement.
You are right.As per A530,only 60% of SMYS is applicable and it does cover welded pipes that too 'long seams'.So circumferential welds should be a 'cakewalk!"
By the way MSL tests 10" Sch 40 pipe at 1600 psi(67% of SMYS) and ISMT tests at 1430 psi(60% of SMYS)
Regards
Aarpee
On 10/10/08, Bathula Raghuram (Mumbai - PIPING) <R.Bathula@ticb.com> wrote:
I have few concerns before going further
1. no jointers are permitted unless agreed by the purchaser
2. where from you got 75% SMYS?
3. why do u want to certify this weld to A106? and not as per construction code!
In my opinion it should, A 530 does also cover welded pipes which are hydro tested to 60% SMYS, if a longitudinal weld is subjected that pressure, then why can't a circumferential weld?
-----Original Message-----
From: materials-welding@googlegroups.com
[mailto:materials-welding@googlegroups.com]On Behalf Of Aarpee
Sent: Friday, October 10, 2008 11:16 AM
To: Materials & Welding
Subject: [MW:1198] Hydro test pressure withstanding
Standard Hydro test pressure for a pipe mfr for 10"NB Sch 40 A106GRB
pipe as per A530 shall be 1426 psi(based on 60%of SMYS) and Alternate
pressure shall be 1783 psi(based on 75% of SMYS).If I am required to
hydrotest a weld between two such pipes at a pressure at which pipe is
hydrotested at mill i.e.1783 psi,will the weld withstand this pressure?
This is in deviation to normal 1.3 or 1.5 times Design Pressure which
in present case works out to be only 1045 psi.The weld shall be made
by E7018-1 electrode and 100% radiographed.In my opinion since the
weld metal is equally compatible with respect to Parent pipe
properties,testing the weld at 1783 psi should pose no problem.Second
opinion is however sought from the group.
Regards
Aarpee
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