RE: [MW:4594] RE: 4582] corrosion problem in TP321 pipes after hydrotesting

Hi Francis,

Thanks for sharing the info

Currently, we must ensure 30ppm for such tests and we engage vendors for the loan of Caxion exchangers for the works

After which, we sent the water sample for lab test to confirm the chloride content

The original certificate shall be provided before the tests

Thank you,

Best Regards.

David Chan

Singapore

From: materials-welding@googlegroups.com [mailto:materials-welding@googlegroups.com] On Behalf Of francis.lobo@indiatimes.com
Sent: Tuesday, March 23, 2010 1:03 AM
To: materials-welding@googlegroups.com
Subject: Re: [MW:4592] RE: 4582] corrosion problem in TP321 pipes after hydrotesting

Dear Friends,
First of all water used for testing with 120 ppm is not suitable for hydro testing of SS Piping , Normally to test ss 321 piping in hydro cracker units we had used DM Water during my old days at sites , Even if use water with high chloride content you must flush the line and dry it so that corrosion could have been avoided .

Best Regards,

Francis lobo

----- Original Message -----
From: Bathula Raghuram (Mumbai - PIPING)
To: materials-welding@googlegroups.com
Sent: Fri, 19 Mar 2010 17:04:12 +0530 (IST)
Subject: [MW:4584] RE: 4582] corrosion problem in TP321 pipes after hydrotesting

preliminary assumption may be because of chloride deposits, more
information is necessary for an appropriate conclusion.

1.
what do you mean by testing partially?

2. is
it commissioned or lying idle after testing?

3. if
commissioned or put into operation, what is the service fluid and operating
conditions?

4.
leaking from where? Welded joints, or basematerial?

5.
pipe is of seamless or welded construction?

6.
did you check the inside surface now? how its look like and your
observations?

this data will be
helpful to all for analyzing as well as learning!

From: materials-welding@googlegroups.com
[mailto:materials-welding@googlegroups.com] On Behalf Of biju
psl
Sent: Friday, March 19, 2010 4:43 PM
To:
materials-welding@googlegroups.com
Subject: [MW:4582] corrosion
problem in TP321 pipes after hydrotesting

Hi,

We have a 2"Sch-40 A312TP321 piping .We tested the above line 4 months
before partially and accepted. Same line when we tested again now it started
leaking at several locations(welds and pipe)We tested the water used for testing
the line and found that the chloride content is 120ppm

Is it possible that just because of this high chloride content the line
starts leaking within 3 months?

best regards,

BIJU

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