[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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