Failure Analysis?

[dursosono]

Does anyone know, what happen in this material?

What type of that corrosion?

How can this occurs?

This is flowline with some data
-Material : NPS 4, API 5L-B, Sch 40
-Remaining thk : average 1 – 2 mm
-Date of construction : July, 2006
-Operating pressure : 225 psi
-Operating temp. : 80 F
-Service : Gas
-Flow rate : 1.5 – 2.0 MMCFD
-Distance from wellhead : 1.5 Km
-Location : straight line, under ground, before scrubber
-Position of corroded area : 6 O’clock
-Date of failure : Dec, 2008

 

[stanweld]

I had similar problem once where water in the stream condensed and reacted with CO2 in the stream to produce carbonic acid. You need to provide more info as to stream makeup.

 

[SJones]

Looks like classic CO2 corrosion but should be confirmed by an review of process conditions and a laboratory examination. Sticking a picture on Eng Tips, although pretty, is not the way to undertake failure analysis!

Steve Jones
Materials & Corrosion Engineer

http://www.linkedin.com/pub/8/83b/b04

 

[strider6]

you should give some informations about water cut, water quality and % of CO2, and H2S if any... then is possible to make some calculation and see if is possible to say that is due to CO2 corrosion..

S

Corrosion Prevention & Corrosion Control

 

[rodneybennet]

Maybe the following thread: Service Life of Pipe for Supercritical Saturated CO2 (

http://www.composite-agency.com/messages/4758.html)

is also of your interest.

Regards,
Rodney