Skip to main content

Re: [MW:4592] RE: 4582] corrosion problem in TP321 pipes after hydrotesting

By Materials & Welding

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









--

To post to this group, send email to materials-welding@googlegroups.com

To unsubscribe from this group, send email to materials-welding-unsubscribe@googlegroups.com

For more options, visit this group's bolg at http://materials-welding.blogspot.com/

The views expressed/exchnaged in this group are members personel views and meant for educational purposes only, Users must take their own decisions w.r.t. applicable code/standard/contract documents.

 

To unsubscribe from this group, send email to materials-welding+unsubscribegooglegroups.com or reply to this email with the words "REMOVE ME" as the subject.



--
Click for exclusive coverage on the New Bajaj Pulsar 220 the fastest Indian bike

Comments

Post a Comment

Popular posts from this blog

Heat tint (temper) colours on stainless steel surfaces heated in air // Heat tint

By Materials & Welding
Introduction The colour formed when stainless steel is heated, either in a furnace application or in the heat affected zone of welds, is dependent on several factors that are related to the oxidation resistance of the steel. The heat tint or temper colour formed is caused by the progressive thickening of the surface oxide layer and so, as temperature is increased, the colours change.   Oxidation resistance of stainless steels However, there are several factors that affect the degree of colour change and so there is no a single table of colour and temperature that represents all cases. The colours formed can only be used as an indication of the temperature to which the steel has been heated. Factors affecting the heat tint colours formed Steel composition The chromium content is the most important single factor affecting oxidation resistance. The higher the chromium, the more heat resistant the steel and so the development of the heat tint colou...
Post a Comment
Read more

Materails FAQs

By Materials & Welding
Q: What are equivalents for standard Q 235 B (and Q 235 A) for U-channels? (asked by: boris.vielhaber@vait.com) A: DIN Nr. = 2393 T.2, 2394 T.2, EN 10025 W. Nr. DIN 17007 = 1.0038 Design DIN 17006 = RSt 37-2, S235JRG2 (Fe 360 B) Q: What is St DIN 2391 BK material? (asked by: dmcandrews@automaticstamp.com) A: Precision steel tubes, cold-finished/hard. Q: What is C.D.W. Boiler Tube? (asked by: montydude123@yahoo.com) A: Cold Drawn Welded Boiler Tube. Q: WHAT IS W.Nr. 1.4301? PLS TELL US IN EASY LANGUAGUE (asked...
21 comments
Read more

The Schaeffler and Delong diagrams for predicting ferrite levels in austenitic stainless steel welds

By Materials & Welding
Introduction Ferrite is important in avoiding hot cracking in during cooling from welding of austenitic stainless steels. 'Constitution diagrams' are used to predict ferrite levels from the composition by comparing the effects of austenite and ferrite stabilising elements. The Schaeffler and Delong diagrams are the original methods of predicting the phase balances in austenitic stainless steel welds. Nickel and chromium equivalents A 'nickel equivalent' is calculated for the austenite stabilising elements and a 'chromium equivalent' ferrite stabilising elements. These are used as the axes for the diagrams, which show the compositional equivalent areas where the phases austenite, ferrite, martensite (and mixtures of these) should be present. Although intended to show the phase balance of weld fillers, these diagrams can also be used to illustrate the phase balance of the 'parent' material. There are different diagrams for dif...
Post a Comment
Read more